xref: /openbmc/linux/drivers/platform/x86/think-lmi.c (revision 9a29f5fc)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Think LMI BIOS configuration driver
4  *
5  * Copyright(C) 2019-2021 Lenovo
6  *
7  * Original code from Thinkpad-wmi project https://github.com/iksaif/thinkpad-wmi
8  * Copyright(C) 2017 Corentin Chary <corentin.chary@gmail.com>
9  * Distributed under the GPL-2.0 license
10  */
11 
12 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
13 
14 #include <linux/acpi.h>
15 #include <linux/errno.h>
16 #include <linux/fs.h>
17 #include <linux/string.h>
18 #include <linux/types.h>
19 #include <linux/dmi.h>
20 #include <linux/wmi.h>
21 #include "firmware_attributes_class.h"
22 #include "think-lmi.h"
23 
24 static bool debug_support;
25 module_param(debug_support, bool, 0444);
26 MODULE_PARM_DESC(debug_support, "Enable debug command support");
27 
28 /*
29  * Name: BiosSetting
30  * Description: Get item name and settings for current LMI instance.
31  * Type: Query
32  * Returns: "Item,Value"
33  * Example: "WakeOnLAN,Enable"
34  */
35 #define LENOVO_BIOS_SETTING_GUID "51F5230E-9677-46CD-A1CF-C0B23EE34DB7"
36 
37 /*
38  * Name: SetBiosSetting
39  * Description: Change the BIOS setting to the desired value using the SetBiosSetting
40  *  class. To save the settings, use the SaveBiosSetting class.
41  *  BIOS settings and values are case sensitive.
42  *  After making changes to the BIOS settings, you must reboot the computer
43  *  before the changes will take effect.
44  * Type: Method
45  * Arguments: "Item,Value,Password,Encoding,KbdLang;"
46  * Example: "WakeOnLAN,Disable,pa55w0rd,ascii,us;"
47  */
48 #define LENOVO_SET_BIOS_SETTINGS_GUID "98479A64-33F5-4E33-A707-8E251EBBC3A1"
49 
50 /*
51  * Name: SaveBiosSettings
52  * Description: Save any pending changes in settings.
53  * Type: Method
54  * Arguments: "Password,Encoding,KbdLang;"
55  * Example: "pa55w0rd,ascii,us;"
56  */
57 #define LENOVO_SAVE_BIOS_SETTINGS_GUID "6A4B54EF-A5ED-4D33-9455-B0D9B48DF4B3"
58 
59 /*
60  * Name: BiosPasswordSettings
61  * Description: Return BIOS Password settings
62  * Type: Query
63  * Returns: PasswordMode, PasswordState, MinLength, MaxLength,
64  *  SupportedEncoding, SupportedKeyboard
65  */
66 #define LENOVO_BIOS_PASSWORD_SETTINGS_GUID "8ADB159E-1E32-455C-BC93-308A7ED98246"
67 
68 /*
69  * Name: SetBiosPassword
70  * Description: Change a specific password.
71  *  - BIOS settings cannot be changed at the same boot as power-on
72  *    passwords (POP) and hard disk passwords (HDP). If you want to change
73  *    BIOS settings and POP or HDP, you must reboot the system after changing
74  *    one of them.
75  *  - A password cannot be set using this method when one does not already
76  *    exist. Passwords can only be updated or cleared.
77  * Type: Method
78  * Arguments: "PasswordType,CurrentPassword,NewPassword,Encoding,KbdLang;"
79  * Example: "pop,pa55w0rd,newpa55w0rd,ascii,us;”
80  */
81 #define LENOVO_SET_BIOS_PASSWORD_GUID "2651D9FD-911C-4B69-B94E-D0DED5963BD7"
82 
83 /*
84  * Name: GetBiosSelections
85  * Description: Return a list of valid settings for a given item.
86  * Type: Method
87  * Arguments: "Item"
88  * Returns: "Value1,Value2,Value3,..."
89  * Example:
90  *  -> "FlashOverLAN"
91  *  <- "Enabled,Disabled"
92  */
93 #define LENOVO_GET_BIOS_SELECTIONS_GUID	"7364651A-132F-4FE7-ADAA-40C6C7EE2E3B"
94 
95 /*
96  * Name: DebugCmd
97  * Description: Debug entry method for entering debug commands to the BIOS
98  */
99 #define LENOVO_DEBUG_CMD_GUID "7FF47003-3B6C-4E5E-A227-E979824A85D1"
100 
101 /*
102  * Name: OpcodeIF
103  * Description: Opcode interface which provides the ability to set multiple
104  *  parameters and then trigger an action with a final command.
105  *  This is particularly useful for simplifying setting passwords.
106  *  With this support comes the ability to set System, HDD and NVMe
107  *  passwords.
108  *  This is currently available on ThinkCenter and ThinkStations platforms
109  */
110 #define LENOVO_OPCODE_IF_GUID "DFDDEF2C-57D4-48ce-B196-0FB787D90836"
111 
112 /*
113  * Name: SetBiosCert
114  * Description: Install BIOS certificate.
115  * Type: Method
116  * Arguments: "Certificate,Password"
117  * You must reboot the computer before the changes will take effect.
118  */
119 #define LENOVO_SET_BIOS_CERT_GUID    "26861C9F-47E9-44C4-BD8B-DFE7FA2610FE"
120 
121 /*
122  * Name: UpdateBiosCert
123  * Description: Update BIOS certificate.
124  * Type: Method
125  * Format: "Certificate,Signature"
126  * You must reboot the computer before the changes will take effect.
127  */
128 #define LENOVO_UPDATE_BIOS_CERT_GUID "9AA3180A-9750-41F7-B9F7-D5D3B1BAC3CE"
129 
130 /*
131  * Name: ClearBiosCert
132  * Description: Uninstall BIOS certificate.
133  * Type: Method
134  * Format: "Serial,Signature"
135  * You must reboot the computer before the changes will take effect.
136  */
137 #define LENOVO_CLEAR_BIOS_CERT_GUID  "B2BC39A7-78DD-4D71-B059-A510DEC44890"
138 /*
139  * Name: CertToPassword
140  * Description: Switch from certificate to password authentication.
141  * Type: Method
142  * Format: "Password,Signature"
143  * You must reboot the computer before the changes will take effect.
144  */
145 #define LENOVO_CERT_TO_PASSWORD_GUID "0DE8590D-5510-4044-9621-77C227F5A70D"
146 
147 /*
148  * Name: SetBiosSettingCert
149  * Description: Set attribute using certificate authentication.
150  * Type: Method
151  * Format: "Item,Value,Signature"
152  */
153 #define LENOVO_SET_BIOS_SETTING_CERT_GUID  "34A008CC-D205-4B62-9E67-31DFA8B90003"
154 
155 /*
156  * Name: SaveBiosSettingCert
157  * Description: Save any pending changes in settings.
158  * Type: Method
159  * Format: "Signature"
160  */
161 #define LENOVO_SAVE_BIOS_SETTING_CERT_GUID "C050FB9D-DF5F-4606-B066-9EFC401B2551"
162 
163 /*
164  * Name: CertThumbprint
165  * Description: Display Certificate thumbprints
166  * Type: Query
167  * Returns: MD5, SHA1 & SHA256 thumbprints
168  */
169 #define LENOVO_CERT_THUMBPRINT_GUID "C59119ED-1C0D-4806-A8E9-59AA318176C4"
170 
171 #define TLMI_POP_PWD (1 << 0)
172 #define TLMI_PAP_PWD (1 << 1)
173 #define TLMI_HDD_PWD (1 << 2)
174 #define TLMI_SYS_PWD (1 << 3)
175 #define TLMI_CERT    (1 << 7)
176 
177 #define to_tlmi_pwd_setting(kobj)  container_of(kobj, struct tlmi_pwd_setting, kobj)
178 #define to_tlmi_attr_setting(kobj)  container_of(kobj, struct tlmi_attr_setting, kobj)
179 
180 static const struct tlmi_err_codes tlmi_errs[] = {
181 	{"Success", 0},
182 	{"Not Supported", -EOPNOTSUPP},
183 	{"Invalid Parameter", -EINVAL},
184 	{"Access Denied", -EACCES},
185 	{"System Busy", -EBUSY},
186 };
187 
188 static const char * const encoding_options[] = {
189 	[TLMI_ENCODING_ASCII] = "ascii",
190 	[TLMI_ENCODING_SCANCODE] = "scancode",
191 };
192 static const char * const level_options[] = {
193 	[TLMI_LEVEL_USER] = "user",
194 	[TLMI_LEVEL_MASTER] = "master",
195 };
196 static struct think_lmi tlmi_priv;
197 static struct class *fw_attr_class;
198 
199 /* ------ Utility functions ------------*/
200 /* Strip out CR if one is present */
201 static void strip_cr(char *str)
202 {
203 	char *p = strchrnul(str, '\n');
204 	*p = '\0';
205 }
206 
207 /* Convert BIOS WMI error string to suitable error code */
208 static int tlmi_errstr_to_err(const char *errstr)
209 {
210 	int i;
211 
212 	for (i = 0; i < sizeof(tlmi_errs)/sizeof(struct tlmi_err_codes); i++) {
213 		if (!strcmp(tlmi_errs[i].err_str, errstr))
214 			return tlmi_errs[i].err_code;
215 	}
216 	return -EPERM;
217 }
218 
219 /* Extract error string from WMI return buffer */
220 static int tlmi_extract_error(const struct acpi_buffer *output)
221 {
222 	const union acpi_object *obj;
223 
224 	obj = output->pointer;
225 	if (!obj)
226 		return -ENOMEM;
227 	if (obj->type != ACPI_TYPE_STRING || !obj->string.pointer)
228 		return -EIO;
229 
230 	return tlmi_errstr_to_err(obj->string.pointer);
231 }
232 
233 /* Utility function to execute WMI call to BIOS */
234 static int tlmi_simple_call(const char *guid, const char *arg)
235 {
236 	const struct acpi_buffer input = { strlen(arg), (char *)arg };
237 	struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
238 	acpi_status status;
239 	int i, err;
240 
241 	/*
242 	 * Duplicated call required to match BIOS workaround for behavior
243 	 * seen when WMI accessed via scripting on other OS.
244 	 */
245 	for (i = 0; i < 2; i++) {
246 		/* (re)initialize output buffer to default state */
247 		output.length = ACPI_ALLOCATE_BUFFER;
248 		output.pointer = NULL;
249 
250 		status = wmi_evaluate_method(guid, 0, 0, &input, &output);
251 		if (ACPI_FAILURE(status)) {
252 			kfree(output.pointer);
253 			return -EIO;
254 		}
255 		err = tlmi_extract_error(&output);
256 		kfree(output.pointer);
257 		if (err)
258 			return err;
259 	}
260 	return 0;
261 }
262 
263 /* Extract output string from WMI return buffer */
264 static int tlmi_extract_output_string(const struct acpi_buffer *output,
265 				      char **string)
266 {
267 	const union acpi_object *obj;
268 	char *s;
269 
270 	obj = output->pointer;
271 	if (!obj)
272 		return -ENOMEM;
273 	if (obj->type != ACPI_TYPE_STRING || !obj->string.pointer)
274 		return -EIO;
275 
276 	s = kstrdup(obj->string.pointer, GFP_KERNEL);
277 	if (!s)
278 		return -ENOMEM;
279 	*string = s;
280 	return 0;
281 }
282 
283 /* ------ Core interface functions ------------*/
284 
285 /* Get password settings from BIOS */
286 static int tlmi_get_pwd_settings(struct tlmi_pwdcfg *pwdcfg)
287 {
288 	struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
289 	const union acpi_object *obj;
290 	acpi_status status;
291 	int copy_size;
292 
293 	if (!tlmi_priv.can_get_password_settings)
294 		return -EOPNOTSUPP;
295 
296 	status = wmi_query_block(LENOVO_BIOS_PASSWORD_SETTINGS_GUID, 0,
297 				 &output);
298 	if (ACPI_FAILURE(status))
299 		return -EIO;
300 
301 	obj = output.pointer;
302 	if (!obj)
303 		return -ENOMEM;
304 	if (obj->type != ACPI_TYPE_BUFFER || !obj->buffer.pointer) {
305 		kfree(obj);
306 		return -EIO;
307 	}
308 	/*
309 	 * The size of thinkpad_wmi_pcfg on ThinkStation is larger than ThinkPad.
310 	 * To make the driver compatible on different brands, we permit it to get
311 	 * the data in below case.
312 	 * Settings must have at minimum the core fields available
313 	 */
314 	if (obj->buffer.length < sizeof(struct tlmi_pwdcfg_core)) {
315 		pr_warn("Unknown pwdcfg buffer length %d\n", obj->buffer.length);
316 		kfree(obj);
317 		return -EIO;
318 	}
319 
320 	copy_size = obj->buffer.length < sizeof(struct tlmi_pwdcfg) ?
321 		obj->buffer.length : sizeof(struct tlmi_pwdcfg);
322 	memcpy(pwdcfg, obj->buffer.pointer, copy_size);
323 	kfree(obj);
324 
325 	if (WARN_ON(pwdcfg->core.max_length >= TLMI_PWD_BUFSIZE))
326 		pwdcfg->core.max_length = TLMI_PWD_BUFSIZE - 1;
327 	return 0;
328 }
329 
330 static int tlmi_save_bios_settings(const char *password)
331 {
332 	return tlmi_simple_call(LENOVO_SAVE_BIOS_SETTINGS_GUID,
333 				password);
334 }
335 
336 static int tlmi_opcode_setting(char *setting, const char *value)
337 {
338 	char *opcode_str;
339 	int ret;
340 
341 	opcode_str = kasprintf(GFP_KERNEL, "%s:%s;", setting, value);
342 	if (!opcode_str)
343 		return -ENOMEM;
344 
345 	ret = tlmi_simple_call(LENOVO_OPCODE_IF_GUID, opcode_str);
346 	kfree(opcode_str);
347 	return ret;
348 }
349 
350 static int tlmi_setting(int item, char **value, const char *guid_string)
351 {
352 	struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
353 	acpi_status status;
354 	int ret;
355 
356 	status = wmi_query_block(guid_string, item, &output);
357 	if (ACPI_FAILURE(status)) {
358 		kfree(output.pointer);
359 		return -EIO;
360 	}
361 
362 	ret = tlmi_extract_output_string(&output, value);
363 	kfree(output.pointer);
364 	return ret;
365 }
366 
367 static int tlmi_get_bios_selections(const char *item, char **value)
368 {
369 	const struct acpi_buffer input = { strlen(item), (char *)item };
370 	struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
371 	acpi_status status;
372 	int ret;
373 
374 	status = wmi_evaluate_method(LENOVO_GET_BIOS_SELECTIONS_GUID,
375 				     0, 0, &input, &output);
376 
377 	if (ACPI_FAILURE(status)) {
378 		kfree(output.pointer);
379 		return -EIO;
380 	}
381 
382 	ret = tlmi_extract_output_string(&output, value);
383 	kfree(output.pointer);
384 	return ret;
385 }
386 
387 /* ---- Authentication sysfs --------------------------------------------------------- */
388 static ssize_t is_enabled_show(struct kobject *kobj, struct kobj_attribute *attr,
389 					  char *buf)
390 {
391 	struct tlmi_pwd_setting *setting = to_tlmi_pwd_setting(kobj);
392 
393 	return sysfs_emit(buf, "%d\n", setting->valid);
394 }
395 
396 static struct kobj_attribute auth_is_pass_set = __ATTR_RO(is_enabled);
397 
398 static ssize_t current_password_store(struct kobject *kobj,
399 				      struct kobj_attribute *attr,
400 				      const char *buf, size_t count)
401 {
402 	struct tlmi_pwd_setting *setting = to_tlmi_pwd_setting(kobj);
403 	size_t pwdlen;
404 
405 	pwdlen = strlen(buf);
406 	/* pwdlen == 0 is allowed to clear the password */
407 	if (pwdlen && ((pwdlen < setting->minlen) || (pwdlen > setting->maxlen)))
408 		return -EINVAL;
409 
410 	strscpy(setting->password, buf, setting->maxlen);
411 	/* Strip out CR if one is present, setting password won't work if it is present */
412 	strip_cr(setting->password);
413 	return count;
414 }
415 
416 static struct kobj_attribute auth_current_password = __ATTR_WO(current_password);
417 
418 static ssize_t new_password_store(struct kobject *kobj,
419 				  struct kobj_attribute *attr,
420 				  const char *buf, size_t count)
421 {
422 	struct tlmi_pwd_setting *setting = to_tlmi_pwd_setting(kobj);
423 	char *auth_str, *new_pwd;
424 	size_t pwdlen;
425 	int ret;
426 
427 	if (!capable(CAP_SYS_ADMIN))
428 		return -EPERM;
429 
430 	if (!tlmi_priv.can_set_bios_password)
431 		return -EOPNOTSUPP;
432 
433 	new_pwd = kstrdup(buf, GFP_KERNEL);
434 	if (!new_pwd)
435 		return -ENOMEM;
436 
437 	/* Strip out CR if one is present, setting password won't work if it is present */
438 	strip_cr(new_pwd);
439 
440 	pwdlen = strlen(new_pwd);
441 	/* pwdlen == 0 is allowed to clear the password */
442 	if (pwdlen && ((pwdlen < setting->minlen) || (pwdlen > setting->maxlen))) {
443 		ret = -EINVAL;
444 		goto out;
445 	}
446 
447 	/* If opcode support is present use that interface */
448 	if (tlmi_priv.opcode_support) {
449 		char pwd_type[8];
450 
451 		/* Special handling required for HDD and NVMe passwords */
452 		if (setting == tlmi_priv.pwd_hdd) {
453 			if (setting->level == TLMI_LEVEL_USER)
454 				sprintf(pwd_type, "uhdp%d", setting->index);
455 			else
456 				sprintf(pwd_type, "mhdp%d", setting->index);
457 		} else if (setting == tlmi_priv.pwd_nvme) {
458 			if (setting->level == TLMI_LEVEL_USER)
459 				sprintf(pwd_type, "unvp%d", setting->index);
460 			else
461 				sprintf(pwd_type, "mnvp%d", setting->index);
462 		} else {
463 			sprintf(pwd_type, "%s", setting->pwd_type);
464 		}
465 
466 		ret = tlmi_opcode_setting("WmiOpcodePasswordType", pwd_type);
467 		if (ret)
468 			goto out;
469 
470 		if (tlmi_priv.pwd_admin->valid) {
471 			ret = tlmi_opcode_setting("WmiOpcodePasswordAdmin",
472 					tlmi_priv.pwd_admin->password);
473 			if (ret)
474 				goto out;
475 		}
476 		ret = tlmi_opcode_setting("WmiOpcodePasswordCurrent01", setting->password);
477 		if (ret)
478 			goto out;
479 		ret = tlmi_opcode_setting("WmiOpcodePasswordNew01", new_pwd);
480 		if (ret)
481 			goto out;
482 		ret = tlmi_simple_call(LENOVO_OPCODE_IF_GUID, "WmiOpcodePasswordSetUpdate;");
483 	} else {
484 		/* Format: 'PasswordType,CurrentPw,NewPw,Encoding,KbdLang;' */
485 		auth_str = kasprintf(GFP_KERNEL, "%s,%s,%s,%s,%s;",
486 				setting->pwd_type, setting->password, new_pwd,
487 				encoding_options[setting->encoding], setting->kbdlang);
488 		if (!auth_str) {
489 			ret = -ENOMEM;
490 			goto out;
491 		}
492 		ret = tlmi_simple_call(LENOVO_SET_BIOS_PASSWORD_GUID, auth_str);
493 		kfree(auth_str);
494 	}
495 out:
496 	kfree(new_pwd);
497 	return ret ?: count;
498 }
499 
500 static struct kobj_attribute auth_new_password = __ATTR_WO(new_password);
501 
502 static ssize_t min_password_length_show(struct kobject *kobj, struct kobj_attribute *attr,
503 			 char *buf)
504 {
505 	struct tlmi_pwd_setting *setting = to_tlmi_pwd_setting(kobj);
506 
507 	return sysfs_emit(buf, "%d\n", setting->minlen);
508 }
509 
510 static struct kobj_attribute auth_min_pass_length = __ATTR_RO(min_password_length);
511 
512 static ssize_t max_password_length_show(struct kobject *kobj, struct kobj_attribute *attr,
513 			 char *buf)
514 {
515 	struct tlmi_pwd_setting *setting = to_tlmi_pwd_setting(kobj);
516 
517 	return sysfs_emit(buf, "%d\n", setting->maxlen);
518 }
519 static struct kobj_attribute auth_max_pass_length = __ATTR_RO(max_password_length);
520 
521 static ssize_t mechanism_show(struct kobject *kobj, struct kobj_attribute *attr,
522 			 char *buf)
523 {
524 	return sysfs_emit(buf, "password\n");
525 }
526 static struct kobj_attribute auth_mechanism = __ATTR_RO(mechanism);
527 
528 static ssize_t encoding_show(struct kobject *kobj, struct kobj_attribute *attr,
529 			 char *buf)
530 {
531 	struct tlmi_pwd_setting *setting = to_tlmi_pwd_setting(kobj);
532 
533 	return sysfs_emit(buf, "%s\n", encoding_options[setting->encoding]);
534 }
535 
536 static ssize_t encoding_store(struct kobject *kobj,
537 				  struct kobj_attribute *attr,
538 				  const char *buf, size_t count)
539 {
540 	struct tlmi_pwd_setting *setting = to_tlmi_pwd_setting(kobj);
541 	int i;
542 
543 	/* Scan for a matching profile */
544 	i = sysfs_match_string(encoding_options, buf);
545 	if (i < 0)
546 		return -EINVAL;
547 
548 	setting->encoding = i;
549 	return count;
550 }
551 
552 static struct kobj_attribute auth_encoding = __ATTR_RW(encoding);
553 
554 static ssize_t kbdlang_show(struct kobject *kobj, struct kobj_attribute *attr,
555 			 char *buf)
556 {
557 	struct tlmi_pwd_setting *setting = to_tlmi_pwd_setting(kobj);
558 
559 	return sysfs_emit(buf, "%s\n", setting->kbdlang);
560 }
561 
562 static ssize_t kbdlang_store(struct kobject *kobj,
563 				  struct kobj_attribute *attr,
564 				  const char *buf, size_t count)
565 {
566 	struct tlmi_pwd_setting *setting = to_tlmi_pwd_setting(kobj);
567 	int length;
568 
569 	/* Calculate length till '\n' or terminating 0 */
570 	length = strchrnul(buf, '\n') - buf;
571 	if (!length || length >= TLMI_LANG_MAXLEN)
572 		return -EINVAL;
573 
574 	memcpy(setting->kbdlang, buf, length);
575 	setting->kbdlang[length] = '\0';
576 	return count;
577 }
578 
579 static struct kobj_attribute auth_kbdlang = __ATTR_RW(kbdlang);
580 
581 static ssize_t role_show(struct kobject *kobj, struct kobj_attribute *attr,
582 			 char *buf)
583 {
584 	struct tlmi_pwd_setting *setting = to_tlmi_pwd_setting(kobj);
585 
586 	return sysfs_emit(buf, "%s\n", setting->role);
587 }
588 static struct kobj_attribute auth_role = __ATTR_RO(role);
589 
590 static ssize_t index_show(struct kobject *kobj, struct kobj_attribute *attr,
591 			 char *buf)
592 {
593 	struct tlmi_pwd_setting *setting = to_tlmi_pwd_setting(kobj);
594 
595 	return sysfs_emit(buf, "%d\n", setting->index);
596 }
597 
598 static ssize_t index_store(struct kobject *kobj,
599 				  struct kobj_attribute *attr,
600 				  const char *buf, size_t count)
601 {
602 	struct tlmi_pwd_setting *setting = to_tlmi_pwd_setting(kobj);
603 	int err, val;
604 
605 	err = kstrtoint(buf, 10, &val);
606 	if (err < 0)
607 		return err;
608 
609 	if (val < 0 || val > TLMI_INDEX_MAX)
610 		return -EINVAL;
611 
612 	setting->index = val;
613 	return count;
614 }
615 
616 static struct kobj_attribute auth_index = __ATTR_RW(index);
617 
618 static ssize_t level_show(struct kobject *kobj, struct kobj_attribute *attr,
619 			 char *buf)
620 {
621 	struct tlmi_pwd_setting *setting = to_tlmi_pwd_setting(kobj);
622 
623 	return sysfs_emit(buf, "%s\n", level_options[setting->level]);
624 }
625 
626 static ssize_t level_store(struct kobject *kobj,
627 				  struct kobj_attribute *attr,
628 				  const char *buf, size_t count)
629 {
630 	struct tlmi_pwd_setting *setting = to_tlmi_pwd_setting(kobj);
631 	int i;
632 
633 	/* Scan for a matching profile */
634 	i = sysfs_match_string(level_options, buf);
635 	if (i < 0)
636 		return -EINVAL;
637 
638 	setting->level = i;
639 	return count;
640 }
641 
642 static struct kobj_attribute auth_level = __ATTR_RW(level);
643 
644 static ssize_t cert_thumbprint(char *buf, const char *arg, int count)
645 {
646 	const struct acpi_buffer input = { strlen(arg), (char *)arg };
647 	struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
648 	const union acpi_object *obj;
649 	acpi_status status;
650 
651 	status = wmi_evaluate_method(LENOVO_CERT_THUMBPRINT_GUID, 0, 0, &input, &output);
652 	if (ACPI_FAILURE(status)) {
653 		kfree(output.pointer);
654 		return -EIO;
655 	}
656 	obj = output.pointer;
657 	if (!obj)
658 		return -ENOMEM;
659 	if (obj->type != ACPI_TYPE_STRING || !obj->string.pointer) {
660 		kfree(output.pointer);
661 		return -EIO;
662 	}
663 	count += sysfs_emit_at(buf, count, "%s : %s\n", arg, (char *)obj->string.pointer);
664 	kfree(output.pointer);
665 
666 	return count;
667 }
668 
669 static ssize_t certificate_thumbprint_show(struct kobject *kobj, struct kobj_attribute *attr,
670 			 char *buf)
671 {
672 	struct tlmi_pwd_setting *setting = to_tlmi_pwd_setting(kobj);
673 	int count = 0;
674 
675 	if (!tlmi_priv.certificate_support || !setting->cert_installed)
676 		return -EOPNOTSUPP;
677 
678 	count += cert_thumbprint(buf, "Md5", count);
679 	count += cert_thumbprint(buf, "Sha1", count);
680 	count += cert_thumbprint(buf, "Sha256", count);
681 	return count;
682 }
683 
684 static struct kobj_attribute auth_cert_thumb = __ATTR_RO(certificate_thumbprint);
685 
686 static ssize_t cert_to_password_store(struct kobject *kobj,
687 				  struct kobj_attribute *attr,
688 				  const char *buf, size_t count)
689 {
690 	struct tlmi_pwd_setting *setting = to_tlmi_pwd_setting(kobj);
691 	char *auth_str, *passwd;
692 	int ret;
693 
694 	if (!capable(CAP_SYS_ADMIN))
695 		return -EPERM;
696 
697 	if (!tlmi_priv.certificate_support)
698 		return -EOPNOTSUPP;
699 
700 	if (!setting->cert_installed)
701 		return -EINVAL;
702 
703 	if (!setting->signature || !setting->signature[0])
704 		return -EACCES;
705 
706 	passwd = kstrdup(buf, GFP_KERNEL);
707 	if (!passwd)
708 		return -ENOMEM;
709 
710 	/* Strip out CR if one is present */
711 	strip_cr(passwd);
712 
713 	/* Format: 'Password,Signature' */
714 	auth_str = kasprintf(GFP_KERNEL, "%s,%s", passwd, setting->signature);
715 	if (!auth_str) {
716 		kfree(passwd);
717 		return -ENOMEM;
718 	}
719 	ret = tlmi_simple_call(LENOVO_CERT_TO_PASSWORD_GUID, auth_str);
720 	kfree(auth_str);
721 	kfree(passwd);
722 
723 	return ret ?: count;
724 }
725 
726 static struct kobj_attribute auth_cert_to_password = __ATTR_WO(cert_to_password);
727 
728 static ssize_t certificate_store(struct kobject *kobj,
729 				  struct kobj_attribute *attr,
730 				  const char *buf, size_t count)
731 {
732 	struct tlmi_pwd_setting *setting = to_tlmi_pwd_setting(kobj);
733 	char *auth_str, *new_cert;
734 	char *guid;
735 	int ret;
736 
737 	if (!capable(CAP_SYS_ADMIN))
738 		return -EPERM;
739 
740 	if (!tlmi_priv.certificate_support)
741 		return -EOPNOTSUPP;
742 
743 	/* If empty then clear installed certificate */
744 	if ((buf[0] == '\0') || (buf[0] == '\n')) { /* Clear installed certificate */
745 		/* Check that signature is set */
746 		if (!setting->signature || !setting->signature[0])
747 			return -EACCES;
748 
749 		/* Format: 'serial#, signature' */
750 		auth_str = kasprintf(GFP_KERNEL, "%s,%s",
751 				dmi_get_system_info(DMI_PRODUCT_SERIAL),
752 				setting->signature);
753 		if (!auth_str)
754 			return -ENOMEM;
755 
756 		ret = tlmi_simple_call(LENOVO_CLEAR_BIOS_CERT_GUID, auth_str);
757 		kfree(auth_str);
758 
759 		return ret ?: count;
760 	}
761 
762 	new_cert = kstrdup(buf, GFP_KERNEL);
763 	if (!new_cert)
764 		return -ENOMEM;
765 	/* Strip out CR if one is present */
766 	strip_cr(new_cert);
767 
768 	if (setting->cert_installed) {
769 		/* Certificate is installed so this is an update */
770 		if (!setting->signature || !setting->signature[0]) {
771 			kfree(new_cert);
772 			return -EACCES;
773 		}
774 		guid = LENOVO_UPDATE_BIOS_CERT_GUID;
775 		/* Format: 'Certificate,Signature' */
776 		auth_str = kasprintf(GFP_KERNEL, "%s,%s",
777 				new_cert, setting->signature);
778 	} else {
779 		/* This is a fresh install */
780 		if (!setting->valid || !setting->password[0]) {
781 			kfree(new_cert);
782 			return -EACCES;
783 		}
784 		guid = LENOVO_SET_BIOS_CERT_GUID;
785 		/* Format: 'Certificate,Admin-password' */
786 		auth_str = kasprintf(GFP_KERNEL, "%s,%s",
787 				new_cert, setting->password);
788 	}
789 	kfree(new_cert);
790 	if (!auth_str)
791 		return -ENOMEM;
792 
793 	ret = tlmi_simple_call(guid, auth_str);
794 	kfree(auth_str);
795 
796 	return ret ?: count;
797 }
798 
799 static struct kobj_attribute auth_certificate = __ATTR_WO(certificate);
800 
801 static ssize_t signature_store(struct kobject *kobj,
802 				  struct kobj_attribute *attr,
803 				  const char *buf, size_t count)
804 {
805 	struct tlmi_pwd_setting *setting = to_tlmi_pwd_setting(kobj);
806 	char *new_signature;
807 
808 	if (!capable(CAP_SYS_ADMIN))
809 		return -EPERM;
810 
811 	if (!tlmi_priv.certificate_support)
812 		return -EOPNOTSUPP;
813 
814 	new_signature = kstrdup(buf, GFP_KERNEL);
815 	if (!new_signature)
816 		return -ENOMEM;
817 
818 	/* Strip out CR if one is present */
819 	strip_cr(new_signature);
820 
821 	/* Free any previous signature */
822 	kfree(setting->signature);
823 	setting->signature = new_signature;
824 
825 	return count;
826 }
827 
828 static struct kobj_attribute auth_signature = __ATTR_WO(signature);
829 
830 static ssize_t save_signature_store(struct kobject *kobj,
831 				  struct kobj_attribute *attr,
832 				  const char *buf, size_t count)
833 {
834 	struct tlmi_pwd_setting *setting = to_tlmi_pwd_setting(kobj);
835 	char *new_signature;
836 
837 	if (!capable(CAP_SYS_ADMIN))
838 		return -EPERM;
839 
840 	if (!tlmi_priv.certificate_support)
841 		return -EOPNOTSUPP;
842 
843 	new_signature = kstrdup(buf, GFP_KERNEL);
844 	if (!new_signature)
845 		return -ENOMEM;
846 
847 	/* Strip out CR if one is present */
848 	strip_cr(new_signature);
849 
850 	/* Free any previous signature */
851 	kfree(setting->save_signature);
852 	setting->save_signature = new_signature;
853 
854 	return count;
855 }
856 
857 static struct kobj_attribute auth_save_signature = __ATTR_WO(save_signature);
858 
859 static umode_t auth_attr_is_visible(struct kobject *kobj,
860 					     struct attribute *attr, int n)
861 {
862 	struct tlmi_pwd_setting *setting = to_tlmi_pwd_setting(kobj);
863 
864 	/* We only want to display level and index settings on HDD/NVMe */
865 	if ((attr == (struct attribute *)&auth_index) ||
866 			(attr == (struct attribute *)&auth_level)) {
867 		if ((setting == tlmi_priv.pwd_hdd) || (setting == tlmi_priv.pwd_nvme))
868 			return attr->mode;
869 		return 0;
870 	}
871 
872 	/* We only display certificates on Admin account, if supported */
873 	if ((attr == (struct attribute *)&auth_certificate) ||
874 			(attr == (struct attribute *)&auth_signature) ||
875 			(attr == (struct attribute *)&auth_save_signature) ||
876 			(attr == (struct attribute *)&auth_cert_thumb) ||
877 			(attr == (struct attribute *)&auth_cert_to_password)) {
878 		if ((setting == tlmi_priv.pwd_admin) && tlmi_priv.certificate_support)
879 			return attr->mode;
880 		return 0;
881 	}
882 
883 	return attr->mode;
884 }
885 
886 static struct attribute *auth_attrs[] = {
887 	&auth_is_pass_set.attr,
888 	&auth_min_pass_length.attr,
889 	&auth_max_pass_length.attr,
890 	&auth_current_password.attr,
891 	&auth_new_password.attr,
892 	&auth_role.attr,
893 	&auth_mechanism.attr,
894 	&auth_encoding.attr,
895 	&auth_kbdlang.attr,
896 	&auth_index.attr,
897 	&auth_level.attr,
898 	&auth_certificate.attr,
899 	&auth_signature.attr,
900 	&auth_save_signature.attr,
901 	&auth_cert_thumb.attr,
902 	&auth_cert_to_password.attr,
903 	NULL
904 };
905 
906 static const struct attribute_group auth_attr_group = {
907 	.is_visible = auth_attr_is_visible,
908 	.attrs = auth_attrs,
909 };
910 
911 /* ---- Attributes sysfs --------------------------------------------------------- */
912 static ssize_t display_name_show(struct kobject *kobj, struct kobj_attribute *attr,
913 		char *buf)
914 {
915 	struct tlmi_attr_setting *setting = to_tlmi_attr_setting(kobj);
916 
917 	return sysfs_emit(buf, "%s\n", setting->display_name);
918 }
919 
920 static ssize_t current_value_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
921 {
922 	struct tlmi_attr_setting *setting = to_tlmi_attr_setting(kobj);
923 	char *item, *value;
924 	int ret;
925 
926 	ret = tlmi_setting(setting->index, &item, LENOVO_BIOS_SETTING_GUID);
927 	if (ret)
928 		return ret;
929 
930 	/* validate and split from `item,value` -> `value` */
931 	value = strpbrk(item, ",");
932 	if (!value || value == item || !strlen(value + 1))
933 		return -EINVAL;
934 
935 	ret = sysfs_emit(buf, "%s\n", value + 1);
936 	kfree(item);
937 	return ret;
938 }
939 
940 static ssize_t possible_values_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
941 {
942 	struct tlmi_attr_setting *setting = to_tlmi_attr_setting(kobj);
943 
944 	if (!tlmi_priv.can_get_bios_selections)
945 		return -EOPNOTSUPP;
946 
947 	return sysfs_emit(buf, "%s\n", setting->possible_values);
948 }
949 
950 static ssize_t current_value_store(struct kobject *kobj,
951 		struct kobj_attribute *attr,
952 		const char *buf, size_t count)
953 {
954 	struct tlmi_attr_setting *setting = to_tlmi_attr_setting(kobj);
955 	char *set_str = NULL, *new_setting = NULL;
956 	char *auth_str = NULL;
957 	int ret;
958 
959 	if (!tlmi_priv.can_set_bios_settings)
960 		return -EOPNOTSUPP;
961 
962 	new_setting = kstrdup(buf, GFP_KERNEL);
963 	if (!new_setting)
964 		return -ENOMEM;
965 
966 	/* Strip out CR if one is present */
967 	strip_cr(new_setting);
968 
969 	/* Check if certificate authentication is enabled and active */
970 	if (tlmi_priv.certificate_support && tlmi_priv.pwd_admin->cert_installed) {
971 		if (!tlmi_priv.pwd_admin->signature || !tlmi_priv.pwd_admin->save_signature) {
972 			ret = -EINVAL;
973 			goto out;
974 		}
975 		set_str = kasprintf(GFP_KERNEL, "%s,%s,%s", setting->display_name,
976 					new_setting, tlmi_priv.pwd_admin->signature);
977 		if (!set_str) {
978 			ret = -ENOMEM;
979 			goto out;
980 		}
981 
982 		ret = tlmi_simple_call(LENOVO_SET_BIOS_SETTING_CERT_GUID, set_str);
983 		if (ret)
984 			goto out;
985 		ret = tlmi_simple_call(LENOVO_SAVE_BIOS_SETTING_CERT_GUID,
986 				tlmi_priv.pwd_admin->save_signature);
987 		if (ret)
988 			goto out;
989 	} else { /* Non certiifcate based authentication */
990 		if (tlmi_priv.pwd_admin->valid && tlmi_priv.pwd_admin->password[0]) {
991 			auth_str = kasprintf(GFP_KERNEL, "%s,%s,%s;",
992 					tlmi_priv.pwd_admin->password,
993 					encoding_options[tlmi_priv.pwd_admin->encoding],
994 					tlmi_priv.pwd_admin->kbdlang);
995 			if (!auth_str) {
996 				ret = -ENOMEM;
997 				goto out;
998 			}
999 		}
1000 
1001 		if (auth_str)
1002 			set_str = kasprintf(GFP_KERNEL, "%s,%s,%s", setting->display_name,
1003 					new_setting, auth_str);
1004 		else
1005 			set_str = kasprintf(GFP_KERNEL, "%s,%s;", setting->display_name,
1006 					new_setting);
1007 		if (!set_str) {
1008 			ret = -ENOMEM;
1009 			goto out;
1010 		}
1011 
1012 		ret = tlmi_simple_call(LENOVO_SET_BIOS_SETTINGS_GUID, set_str);
1013 		if (ret)
1014 			goto out;
1015 
1016 		if (auth_str)
1017 			ret = tlmi_save_bios_settings(auth_str);
1018 		else
1019 			ret = tlmi_save_bios_settings("");
1020 	}
1021 	if (!ret && !tlmi_priv.pending_changes) {
1022 		tlmi_priv.pending_changes = true;
1023 		/* let userland know it may need to check reboot pending again */
1024 		kobject_uevent(&tlmi_priv.class_dev->kobj, KOBJ_CHANGE);
1025 	}
1026 out:
1027 	kfree(auth_str);
1028 	kfree(set_str);
1029 	kfree(new_setting);
1030 	return ret ?: count;
1031 }
1032 
1033 static struct kobj_attribute attr_displ_name = __ATTR_RO(display_name);
1034 
1035 static struct kobj_attribute attr_possible_values = __ATTR_RO(possible_values);
1036 
1037 static struct kobj_attribute attr_current_val = __ATTR_RW_MODE(current_value, 0600);
1038 
1039 static struct attribute *tlmi_attrs[] = {
1040 	&attr_displ_name.attr,
1041 	&attr_current_val.attr,
1042 	&attr_possible_values.attr,
1043 	NULL
1044 };
1045 
1046 static const struct attribute_group tlmi_attr_group = {
1047 	.attrs = tlmi_attrs,
1048 };
1049 
1050 static ssize_t tlmi_attr_show(struct kobject *kobj, struct attribute *attr,
1051 				    char *buf)
1052 {
1053 	struct kobj_attribute *kattr;
1054 
1055 	kattr = container_of(attr, struct kobj_attribute, attr);
1056 	if (kattr->show)
1057 		return kattr->show(kobj, kattr, buf);
1058 	return -EIO;
1059 }
1060 
1061 static ssize_t tlmi_attr_store(struct kobject *kobj, struct attribute *attr,
1062 				     const char *buf, size_t count)
1063 {
1064 	struct kobj_attribute *kattr;
1065 
1066 	kattr = container_of(attr, struct kobj_attribute, attr);
1067 	if (kattr->store)
1068 		return kattr->store(kobj, kattr, buf, count);
1069 	return -EIO;
1070 }
1071 
1072 static const struct sysfs_ops tlmi_kobj_sysfs_ops = {
1073 	.show	= tlmi_attr_show,
1074 	.store	= tlmi_attr_store,
1075 };
1076 
1077 static void tlmi_attr_setting_release(struct kobject *kobj)
1078 {
1079 	struct tlmi_attr_setting *setting = to_tlmi_attr_setting(kobj);
1080 
1081 	kfree(setting->possible_values);
1082 	kfree(setting);
1083 }
1084 
1085 static void tlmi_pwd_setting_release(struct kobject *kobj)
1086 {
1087 	struct tlmi_pwd_setting *setting = to_tlmi_pwd_setting(kobj);
1088 
1089 	kfree(setting);
1090 }
1091 
1092 static struct kobj_type tlmi_attr_setting_ktype = {
1093 	.release        = &tlmi_attr_setting_release,
1094 	.sysfs_ops	= &tlmi_kobj_sysfs_ops,
1095 };
1096 
1097 static struct kobj_type tlmi_pwd_setting_ktype = {
1098 	.release        = &tlmi_pwd_setting_release,
1099 	.sysfs_ops	= &tlmi_kobj_sysfs_ops,
1100 };
1101 
1102 static ssize_t pending_reboot_show(struct kobject *kobj, struct kobj_attribute *attr,
1103 				   char *buf)
1104 {
1105 	return sprintf(buf, "%d\n", tlmi_priv.pending_changes);
1106 }
1107 
1108 static struct kobj_attribute pending_reboot = __ATTR_RO(pending_reboot);
1109 
1110 /* ---- Debug interface--------------------------------------------------------- */
1111 static ssize_t debug_cmd_store(struct kobject *kobj, struct kobj_attribute *attr,
1112 				const char *buf, size_t count)
1113 {
1114 	char *set_str = NULL, *new_setting = NULL;
1115 	char *auth_str = NULL;
1116 	int ret;
1117 
1118 	if (!tlmi_priv.can_debug_cmd)
1119 		return -EOPNOTSUPP;
1120 
1121 	new_setting = kstrdup(buf, GFP_KERNEL);
1122 	if (!new_setting)
1123 		return -ENOMEM;
1124 
1125 	/* Strip out CR if one is present */
1126 	strip_cr(new_setting);
1127 
1128 	if (tlmi_priv.pwd_admin->valid && tlmi_priv.pwd_admin->password[0]) {
1129 		auth_str = kasprintf(GFP_KERNEL, "%s,%s,%s;",
1130 				tlmi_priv.pwd_admin->password,
1131 				encoding_options[tlmi_priv.pwd_admin->encoding],
1132 				tlmi_priv.pwd_admin->kbdlang);
1133 		if (!auth_str) {
1134 			ret = -ENOMEM;
1135 			goto out;
1136 		}
1137 	}
1138 
1139 	if (auth_str)
1140 		set_str = kasprintf(GFP_KERNEL, "%s,%s", new_setting, auth_str);
1141 	else
1142 		set_str = kasprintf(GFP_KERNEL, "%s;", new_setting);
1143 	if (!set_str) {
1144 		ret = -ENOMEM;
1145 		goto out;
1146 	}
1147 
1148 	ret = tlmi_simple_call(LENOVO_DEBUG_CMD_GUID, set_str);
1149 	if (ret)
1150 		goto out;
1151 
1152 	if (!ret && !tlmi_priv.pending_changes) {
1153 		tlmi_priv.pending_changes = true;
1154 		/* let userland know it may need to check reboot pending again */
1155 		kobject_uevent(&tlmi_priv.class_dev->kobj, KOBJ_CHANGE);
1156 	}
1157 out:
1158 	kfree(auth_str);
1159 	kfree(set_str);
1160 	kfree(new_setting);
1161 	return ret ?: count;
1162 }
1163 
1164 static struct kobj_attribute debug_cmd = __ATTR_WO(debug_cmd);
1165 
1166 /* ---- Initialisation --------------------------------------------------------- */
1167 static void tlmi_release_attr(void)
1168 {
1169 	int i;
1170 
1171 	/* Attribute structures */
1172 	for (i = 0; i < TLMI_SETTINGS_COUNT; i++) {
1173 		if (tlmi_priv.setting[i]) {
1174 			sysfs_remove_group(&tlmi_priv.setting[i]->kobj, &tlmi_attr_group);
1175 			kobject_put(&tlmi_priv.setting[i]->kobj);
1176 		}
1177 	}
1178 	sysfs_remove_file(&tlmi_priv.attribute_kset->kobj, &pending_reboot.attr);
1179 	if (tlmi_priv.can_debug_cmd && debug_support)
1180 		sysfs_remove_file(&tlmi_priv.attribute_kset->kobj, &debug_cmd.attr);
1181 
1182 	kset_unregister(tlmi_priv.attribute_kset);
1183 
1184 	/* Free up any saved signatures */
1185 	kfree(tlmi_priv.pwd_admin->signature);
1186 	kfree(tlmi_priv.pwd_admin->save_signature);
1187 
1188 	/* Authentication structures */
1189 	sysfs_remove_group(&tlmi_priv.pwd_admin->kobj, &auth_attr_group);
1190 	kobject_put(&tlmi_priv.pwd_admin->kobj);
1191 	sysfs_remove_group(&tlmi_priv.pwd_power->kobj, &auth_attr_group);
1192 	kobject_put(&tlmi_priv.pwd_power->kobj);
1193 
1194 	if (tlmi_priv.opcode_support) {
1195 		sysfs_remove_group(&tlmi_priv.pwd_system->kobj, &auth_attr_group);
1196 		kobject_put(&tlmi_priv.pwd_system->kobj);
1197 		sysfs_remove_group(&tlmi_priv.pwd_hdd->kobj, &auth_attr_group);
1198 		kobject_put(&tlmi_priv.pwd_hdd->kobj);
1199 		sysfs_remove_group(&tlmi_priv.pwd_nvme->kobj, &auth_attr_group);
1200 		kobject_put(&tlmi_priv.pwd_nvme->kobj);
1201 	}
1202 
1203 	kset_unregister(tlmi_priv.authentication_kset);
1204 }
1205 
1206 static int tlmi_sysfs_init(void)
1207 {
1208 	int i, ret;
1209 
1210 	ret = fw_attributes_class_get(&fw_attr_class);
1211 	if (ret)
1212 		return ret;
1213 
1214 	tlmi_priv.class_dev = device_create(fw_attr_class, NULL, MKDEV(0, 0),
1215 			NULL, "%s", "thinklmi");
1216 	if (IS_ERR(tlmi_priv.class_dev)) {
1217 		ret = PTR_ERR(tlmi_priv.class_dev);
1218 		goto fail_class_created;
1219 	}
1220 
1221 	tlmi_priv.attribute_kset = kset_create_and_add("attributes", NULL,
1222 			&tlmi_priv.class_dev->kobj);
1223 	if (!tlmi_priv.attribute_kset) {
1224 		ret = -ENOMEM;
1225 		goto fail_device_created;
1226 	}
1227 
1228 	for (i = 0; i < TLMI_SETTINGS_COUNT; i++) {
1229 		/* Check if index is a valid setting - skip if it isn't */
1230 		if (!tlmi_priv.setting[i])
1231 			continue;
1232 
1233 		/* check for duplicate or reserved values */
1234 		if (kset_find_obj(tlmi_priv.attribute_kset, tlmi_priv.setting[i]->display_name) ||
1235 		    !strcmp(tlmi_priv.setting[i]->display_name, "Reserved")) {
1236 			pr_debug("duplicate or reserved attribute name found - %s\n",
1237 				tlmi_priv.setting[i]->display_name);
1238 			kfree(tlmi_priv.setting[i]->possible_values);
1239 			kfree(tlmi_priv.setting[i]);
1240 			tlmi_priv.setting[i] = NULL;
1241 			continue;
1242 		}
1243 
1244 		/* Build attribute */
1245 		tlmi_priv.setting[i]->kobj.kset = tlmi_priv.attribute_kset;
1246 		ret = kobject_add(&tlmi_priv.setting[i]->kobj, NULL,
1247 				  "%s", tlmi_priv.setting[i]->display_name);
1248 		if (ret)
1249 			goto fail_create_attr;
1250 
1251 		ret = sysfs_create_group(&tlmi_priv.setting[i]->kobj, &tlmi_attr_group);
1252 		if (ret)
1253 			goto fail_create_attr;
1254 	}
1255 
1256 	ret = sysfs_create_file(&tlmi_priv.attribute_kset->kobj, &pending_reboot.attr);
1257 	if (ret)
1258 		goto fail_create_attr;
1259 
1260 	if (tlmi_priv.can_debug_cmd && debug_support) {
1261 		ret = sysfs_create_file(&tlmi_priv.attribute_kset->kobj, &debug_cmd.attr);
1262 		if (ret)
1263 			goto fail_create_attr;
1264 	}
1265 
1266 	/* Create authentication entries */
1267 	tlmi_priv.authentication_kset = kset_create_and_add("authentication", NULL,
1268 								&tlmi_priv.class_dev->kobj);
1269 	if (!tlmi_priv.authentication_kset) {
1270 		ret = -ENOMEM;
1271 		goto fail_create_attr;
1272 	}
1273 	tlmi_priv.pwd_admin->kobj.kset = tlmi_priv.authentication_kset;
1274 	ret = kobject_add(&tlmi_priv.pwd_admin->kobj, NULL, "%s", "Admin");
1275 	if (ret)
1276 		goto fail_create_attr;
1277 
1278 	ret = sysfs_create_group(&tlmi_priv.pwd_admin->kobj, &auth_attr_group);
1279 	if (ret)
1280 		goto fail_create_attr;
1281 
1282 	tlmi_priv.pwd_power->kobj.kset = tlmi_priv.authentication_kset;
1283 	ret = kobject_add(&tlmi_priv.pwd_power->kobj, NULL, "%s", "Power-on");
1284 	if (ret)
1285 		goto fail_create_attr;
1286 
1287 	ret = sysfs_create_group(&tlmi_priv.pwd_power->kobj, &auth_attr_group);
1288 	if (ret)
1289 		goto fail_create_attr;
1290 
1291 	if (tlmi_priv.opcode_support) {
1292 		tlmi_priv.pwd_system->kobj.kset = tlmi_priv.authentication_kset;
1293 		ret = kobject_add(&tlmi_priv.pwd_system->kobj, NULL, "%s", "System");
1294 		if (ret)
1295 			goto fail_create_attr;
1296 
1297 		ret = sysfs_create_group(&tlmi_priv.pwd_system->kobj, &auth_attr_group);
1298 		if (ret)
1299 			goto fail_create_attr;
1300 
1301 		tlmi_priv.pwd_hdd->kobj.kset = tlmi_priv.authentication_kset;
1302 		ret = kobject_add(&tlmi_priv.pwd_hdd->kobj, NULL, "%s", "HDD");
1303 		if (ret)
1304 			goto fail_create_attr;
1305 
1306 		ret = sysfs_create_group(&tlmi_priv.pwd_hdd->kobj, &auth_attr_group);
1307 		if (ret)
1308 			goto fail_create_attr;
1309 
1310 		tlmi_priv.pwd_nvme->kobj.kset = tlmi_priv.authentication_kset;
1311 		ret = kobject_add(&tlmi_priv.pwd_nvme->kobj, NULL, "%s", "NVMe");
1312 		if (ret)
1313 			goto fail_create_attr;
1314 
1315 		ret = sysfs_create_group(&tlmi_priv.pwd_nvme->kobj, &auth_attr_group);
1316 		if (ret)
1317 			goto fail_create_attr;
1318 	}
1319 
1320 	return ret;
1321 
1322 fail_create_attr:
1323 	tlmi_release_attr();
1324 fail_device_created:
1325 	device_destroy(fw_attr_class, MKDEV(0, 0));
1326 fail_class_created:
1327 	fw_attributes_class_put();
1328 	return ret;
1329 }
1330 
1331 /* ---- Base Driver -------------------------------------------------------- */
1332 static struct tlmi_pwd_setting *tlmi_create_auth(const char *pwd_type,
1333 			    const char *pwd_role)
1334 {
1335 	struct tlmi_pwd_setting *new_pwd;
1336 
1337 	new_pwd = kzalloc(sizeof(struct tlmi_pwd_setting), GFP_KERNEL);
1338 	if (!new_pwd)
1339 		return NULL;
1340 
1341 	strscpy(new_pwd->kbdlang, "us", TLMI_LANG_MAXLEN);
1342 	new_pwd->encoding = TLMI_ENCODING_ASCII;
1343 	new_pwd->pwd_type = pwd_type;
1344 	new_pwd->role = pwd_role;
1345 	new_pwd->minlen = tlmi_priv.pwdcfg.core.min_length;
1346 	new_pwd->maxlen = tlmi_priv.pwdcfg.core.max_length;
1347 	new_pwd->index = 0;
1348 
1349 	kobject_init(&new_pwd->kobj, &tlmi_pwd_setting_ktype);
1350 
1351 	return new_pwd;
1352 }
1353 
1354 static int tlmi_analyze(void)
1355 {
1356 	acpi_status status;
1357 	int i, ret;
1358 
1359 	if (wmi_has_guid(LENOVO_SET_BIOS_SETTINGS_GUID) &&
1360 	    wmi_has_guid(LENOVO_SAVE_BIOS_SETTINGS_GUID))
1361 		tlmi_priv.can_set_bios_settings = true;
1362 
1363 	if (wmi_has_guid(LENOVO_GET_BIOS_SELECTIONS_GUID))
1364 		tlmi_priv.can_get_bios_selections = true;
1365 
1366 	if (wmi_has_guid(LENOVO_SET_BIOS_PASSWORD_GUID))
1367 		tlmi_priv.can_set_bios_password = true;
1368 
1369 	if (wmi_has_guid(LENOVO_BIOS_PASSWORD_SETTINGS_GUID))
1370 		tlmi_priv.can_get_password_settings = true;
1371 
1372 	if (wmi_has_guid(LENOVO_DEBUG_CMD_GUID))
1373 		tlmi_priv.can_debug_cmd = true;
1374 
1375 	if (wmi_has_guid(LENOVO_OPCODE_IF_GUID))
1376 		tlmi_priv.opcode_support = true;
1377 
1378 	if (wmi_has_guid(LENOVO_SET_BIOS_CERT_GUID) &&
1379 		wmi_has_guid(LENOVO_SET_BIOS_SETTING_CERT_GUID) &&
1380 		wmi_has_guid(LENOVO_SAVE_BIOS_SETTING_CERT_GUID))
1381 		tlmi_priv.certificate_support = true;
1382 
1383 	/*
1384 	 * Try to find the number of valid settings of this machine
1385 	 * and use it to create sysfs attributes.
1386 	 */
1387 	for (i = 0; i < TLMI_SETTINGS_COUNT; ++i) {
1388 		struct tlmi_attr_setting *setting;
1389 		char *item = NULL;
1390 		char *p;
1391 
1392 		tlmi_priv.setting[i] = NULL;
1393 		status = tlmi_setting(i, &item, LENOVO_BIOS_SETTING_GUID);
1394 		if (ACPI_FAILURE(status))
1395 			break;
1396 		if (!item)
1397 			break;
1398 		if (!*item) {
1399 			kfree(item);
1400 			continue;
1401 		}
1402 
1403 		/* It is not allowed to have '/' for file name. Convert it into '\'. */
1404 		strreplace(item, '/', '\\');
1405 
1406 		/* Remove the value part */
1407 		p = strchrnul(item, ',');
1408 		*p = '\0';
1409 
1410 		/* Create a setting entry */
1411 		setting = kzalloc(sizeof(*setting), GFP_KERNEL);
1412 		if (!setting) {
1413 			ret = -ENOMEM;
1414 			kfree(item);
1415 			goto fail_clear_attr;
1416 		}
1417 		setting->index = i;
1418 		strscpy(setting->display_name, item, TLMI_SETTINGS_MAXLEN);
1419 		/* If BIOS selections supported, load those */
1420 		if (tlmi_priv.can_get_bios_selections) {
1421 			ret = tlmi_get_bios_selections(setting->display_name,
1422 					&setting->possible_values);
1423 			if (ret || !setting->possible_values)
1424 				pr_info("Error retrieving possible values for %d : %s\n",
1425 						i, setting->display_name);
1426 		}
1427 		kobject_init(&setting->kobj, &tlmi_attr_setting_ktype);
1428 		tlmi_priv.setting[i] = setting;
1429 		kfree(item);
1430 	}
1431 
1432 	/* Create password setting structure */
1433 	ret = tlmi_get_pwd_settings(&tlmi_priv.pwdcfg);
1434 	if (ret)
1435 		goto fail_clear_attr;
1436 
1437 	/* All failures below boil down to kmalloc failures */
1438 	ret = -ENOMEM;
1439 
1440 	tlmi_priv.pwd_admin = tlmi_create_auth("pap", "bios-admin");
1441 	if (!tlmi_priv.pwd_admin)
1442 		goto fail_clear_attr;
1443 
1444 	if (tlmi_priv.pwdcfg.core.password_state & TLMI_PAP_PWD)
1445 		tlmi_priv.pwd_admin->valid = true;
1446 
1447 	tlmi_priv.pwd_power = tlmi_create_auth("pop", "power-on");
1448 	if (!tlmi_priv.pwd_power)
1449 		goto fail_clear_attr;
1450 
1451 	if (tlmi_priv.pwdcfg.core.password_state & TLMI_POP_PWD)
1452 		tlmi_priv.pwd_power->valid = true;
1453 
1454 	if (tlmi_priv.opcode_support) {
1455 		tlmi_priv.pwd_system = tlmi_create_auth("sys", "system");
1456 		if (!tlmi_priv.pwd_system)
1457 			goto fail_clear_attr;
1458 
1459 		if (tlmi_priv.pwdcfg.core.password_state & TLMI_SYS_PWD)
1460 			tlmi_priv.pwd_system->valid = true;
1461 
1462 		tlmi_priv.pwd_hdd = tlmi_create_auth("hdd", "hdd");
1463 		if (!tlmi_priv.pwd_hdd)
1464 			goto fail_clear_attr;
1465 
1466 		tlmi_priv.pwd_nvme = tlmi_create_auth("nvm", "nvme");
1467 		if (!tlmi_priv.pwd_nvme)
1468 			goto fail_clear_attr;
1469 
1470 		if (tlmi_priv.pwdcfg.core.password_state & TLMI_HDD_PWD) {
1471 			/* Check if PWD is configured and set index to first drive found */
1472 			if (tlmi_priv.pwdcfg.ext.hdd_user_password ||
1473 					tlmi_priv.pwdcfg.ext.hdd_master_password) {
1474 				tlmi_priv.pwd_hdd->valid = true;
1475 				if (tlmi_priv.pwdcfg.ext.hdd_master_password)
1476 					tlmi_priv.pwd_hdd->index =
1477 						ffs(tlmi_priv.pwdcfg.ext.hdd_master_password) - 1;
1478 				else
1479 					tlmi_priv.pwd_hdd->index =
1480 						ffs(tlmi_priv.pwdcfg.ext.hdd_user_password) - 1;
1481 			}
1482 			if (tlmi_priv.pwdcfg.ext.nvme_user_password ||
1483 					tlmi_priv.pwdcfg.ext.nvme_master_password) {
1484 				tlmi_priv.pwd_nvme->valid = true;
1485 				if (tlmi_priv.pwdcfg.ext.nvme_master_password)
1486 					tlmi_priv.pwd_nvme->index =
1487 						ffs(tlmi_priv.pwdcfg.ext.nvme_master_password) - 1;
1488 				else
1489 					tlmi_priv.pwd_nvme->index =
1490 						ffs(tlmi_priv.pwdcfg.ext.nvme_user_password) - 1;
1491 			}
1492 		}
1493 	}
1494 
1495 	if (tlmi_priv.certificate_support &&
1496 		(tlmi_priv.pwdcfg.core.password_state & TLMI_CERT))
1497 		tlmi_priv.pwd_admin->cert_installed = true;
1498 
1499 	return 0;
1500 
1501 fail_clear_attr:
1502 	for (i = 0; i < TLMI_SETTINGS_COUNT; ++i) {
1503 		if (tlmi_priv.setting[i]) {
1504 			kfree(tlmi_priv.setting[i]->possible_values);
1505 			kfree(tlmi_priv.setting[i]);
1506 		}
1507 	}
1508 	kfree(tlmi_priv.pwd_admin);
1509 	kfree(tlmi_priv.pwd_power);
1510 	kfree(tlmi_priv.pwd_system);
1511 	kfree(tlmi_priv.pwd_hdd);
1512 	kfree(tlmi_priv.pwd_nvme);
1513 	return ret;
1514 }
1515 
1516 static void tlmi_remove(struct wmi_device *wdev)
1517 {
1518 	tlmi_release_attr();
1519 	device_destroy(fw_attr_class, MKDEV(0, 0));
1520 	fw_attributes_class_put();
1521 }
1522 
1523 static int tlmi_probe(struct wmi_device *wdev, const void *context)
1524 {
1525 	int ret;
1526 
1527 	ret = tlmi_analyze();
1528 	if (ret)
1529 		return ret;
1530 
1531 	return tlmi_sysfs_init();
1532 }
1533 
1534 static const struct wmi_device_id tlmi_id_table[] = {
1535 	{ .guid_string = LENOVO_BIOS_SETTING_GUID },
1536 	{ }
1537 };
1538 MODULE_DEVICE_TABLE(wmi, tlmi_id_table);
1539 
1540 static struct wmi_driver tlmi_driver = {
1541 	.driver = {
1542 		.name = "think-lmi",
1543 	},
1544 	.id_table = tlmi_id_table,
1545 	.probe = tlmi_probe,
1546 	.remove = tlmi_remove,
1547 };
1548 
1549 MODULE_AUTHOR("Sugumaran L <slacshiminar@lenovo.com>");
1550 MODULE_AUTHOR("Mark Pearson <markpearson@lenovo.com>");
1551 MODULE_AUTHOR("Corentin Chary <corentin.chary@gmail.com>");
1552 MODULE_DESCRIPTION("ThinkLMI Driver");
1553 MODULE_LICENSE("GPL");
1554 
1555 module_wmi_driver(tlmi_driver);
1556