xref: /openbmc/linux/drivers/platform/x86/think-lmi.c (revision 335f70fa)
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 	new_cert = kstrdup(buf, GFP_KERNEL);
744 	if (!new_cert)
745 		return -ENOMEM;
746 	/* Strip out CR if one is present */
747 	strip_cr(new_cert);
748 
749 	/* If empty then clear installed certificate */
750 	if (new_cert[0] == '\0') { /* Clear installed certificate */
751 		kfree(new_cert);
752 
753 		/* Check that signature is set */
754 		if (!setting->signature || !setting->signature[0])
755 			return -EACCES;
756 
757 		/* Format: 'serial#, signature' */
758 		auth_str = kasprintf(GFP_KERNEL, "%s,%s",
759 				dmi_get_system_info(DMI_PRODUCT_SERIAL),
760 				setting->signature);
761 		if (!auth_str)
762 			return -ENOMEM;
763 
764 		ret = tlmi_simple_call(LENOVO_CLEAR_BIOS_CERT_GUID, auth_str);
765 		kfree(auth_str);
766 		if (ret)
767 			return ret;
768 
769 		kfree(setting->certificate);
770 		setting->certificate = NULL;
771 		return count;
772 	}
773 
774 	if (setting->cert_installed) {
775 		/* Certificate is installed so this is an update */
776 		if (!setting->signature || !setting->signature[0]) {
777 			kfree(new_cert);
778 			return -EACCES;
779 		}
780 		guid = LENOVO_UPDATE_BIOS_CERT_GUID;
781 		/* Format: 'Certificate,Signature' */
782 		auth_str = kasprintf(GFP_KERNEL, "%s,%s",
783 				new_cert, setting->signature);
784 	} else {
785 		/* This is a fresh install */
786 		if (!setting->valid || !setting->password[0]) {
787 			kfree(new_cert);
788 			return -EACCES;
789 		}
790 		guid = LENOVO_SET_BIOS_CERT_GUID;
791 		/* Format: 'Certificate,Admin-password' */
792 		auth_str = kasprintf(GFP_KERNEL, "%s,%s",
793 				new_cert, setting->password);
794 	}
795 	if (!auth_str) {
796 		kfree(new_cert);
797 		return -ENOMEM;
798 	}
799 
800 	ret = tlmi_simple_call(guid, auth_str);
801 	kfree(auth_str);
802 	if (ret) {
803 		kfree(new_cert);
804 		return ret;
805 	}
806 
807 	kfree(setting->certificate);
808 	setting->certificate = new_cert;
809 	return count;
810 }
811 
812 static struct kobj_attribute auth_certificate = __ATTR_WO(certificate);
813 
814 static ssize_t signature_store(struct kobject *kobj,
815 				  struct kobj_attribute *attr,
816 				  const char *buf, size_t count)
817 {
818 	struct tlmi_pwd_setting *setting = to_tlmi_pwd_setting(kobj);
819 	char *new_signature;
820 
821 	if (!capable(CAP_SYS_ADMIN))
822 		return -EPERM;
823 
824 	if (!tlmi_priv.certificate_support)
825 		return -EOPNOTSUPP;
826 
827 	new_signature = kstrdup(buf, GFP_KERNEL);
828 	if (!new_signature)
829 		return -ENOMEM;
830 
831 	/* Strip out CR if one is present */
832 	strip_cr(new_signature);
833 
834 	/* Free any previous signature */
835 	kfree(setting->signature);
836 	setting->signature = new_signature;
837 
838 	return count;
839 }
840 
841 static struct kobj_attribute auth_signature = __ATTR_WO(signature);
842 
843 static ssize_t save_signature_store(struct kobject *kobj,
844 				  struct kobj_attribute *attr,
845 				  const char *buf, size_t count)
846 {
847 	struct tlmi_pwd_setting *setting = to_tlmi_pwd_setting(kobj);
848 	char *new_signature;
849 
850 	if (!capable(CAP_SYS_ADMIN))
851 		return -EPERM;
852 
853 	if (!tlmi_priv.certificate_support)
854 		return -EOPNOTSUPP;
855 
856 	new_signature = kstrdup(buf, GFP_KERNEL);
857 	if (!new_signature)
858 		return -ENOMEM;
859 
860 	/* Strip out CR if one is present */
861 	strip_cr(new_signature);
862 
863 	/* Free any previous signature */
864 	kfree(setting->save_signature);
865 	setting->save_signature = new_signature;
866 
867 	return count;
868 }
869 
870 static struct kobj_attribute auth_save_signature = __ATTR_WO(save_signature);
871 
872 static umode_t auth_attr_is_visible(struct kobject *kobj,
873 					     struct attribute *attr, int n)
874 {
875 	struct tlmi_pwd_setting *setting = to_tlmi_pwd_setting(kobj);
876 
877 	/* We only want to display level and index settings on HDD/NVMe */
878 	if ((attr == (struct attribute *)&auth_index) ||
879 			(attr == (struct attribute *)&auth_level)) {
880 		if ((setting == tlmi_priv.pwd_hdd) || (setting == tlmi_priv.pwd_nvme))
881 			return attr->mode;
882 		return 0;
883 	}
884 
885 	/* We only display certificates on Admin account, if supported */
886 	if ((attr == (struct attribute *)&auth_certificate) ||
887 			(attr == (struct attribute *)&auth_signature) ||
888 			(attr == (struct attribute *)&auth_save_signature) ||
889 			(attr == (struct attribute *)&auth_cert_thumb) ||
890 			(attr == (struct attribute *)&auth_cert_to_password)) {
891 		if ((setting == tlmi_priv.pwd_admin) && tlmi_priv.certificate_support)
892 			return attr->mode;
893 		return 0;
894 	}
895 
896 	return attr->mode;
897 }
898 
899 static struct attribute *auth_attrs[] = {
900 	&auth_is_pass_set.attr,
901 	&auth_min_pass_length.attr,
902 	&auth_max_pass_length.attr,
903 	&auth_current_password.attr,
904 	&auth_new_password.attr,
905 	&auth_role.attr,
906 	&auth_mechanism.attr,
907 	&auth_encoding.attr,
908 	&auth_kbdlang.attr,
909 	&auth_index.attr,
910 	&auth_level.attr,
911 	&auth_certificate.attr,
912 	&auth_signature.attr,
913 	&auth_save_signature.attr,
914 	&auth_cert_thumb.attr,
915 	&auth_cert_to_password.attr,
916 	NULL
917 };
918 
919 static const struct attribute_group auth_attr_group = {
920 	.is_visible = auth_attr_is_visible,
921 	.attrs = auth_attrs,
922 };
923 
924 /* ---- Attributes sysfs --------------------------------------------------------- */
925 static ssize_t display_name_show(struct kobject *kobj, struct kobj_attribute *attr,
926 		char *buf)
927 {
928 	struct tlmi_attr_setting *setting = to_tlmi_attr_setting(kobj);
929 
930 	return sysfs_emit(buf, "%s\n", setting->display_name);
931 }
932 
933 static ssize_t current_value_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
934 {
935 	struct tlmi_attr_setting *setting = to_tlmi_attr_setting(kobj);
936 	char *item, *value;
937 	int ret;
938 
939 	ret = tlmi_setting(setting->index, &item, LENOVO_BIOS_SETTING_GUID);
940 	if (ret)
941 		return ret;
942 
943 	/* validate and split from `item,value` -> `value` */
944 	value = strpbrk(item, ",");
945 	if (!value || value == item || !strlen(value + 1))
946 		return -EINVAL;
947 
948 	ret = sysfs_emit(buf, "%s\n", value + 1);
949 	kfree(item);
950 	return ret;
951 }
952 
953 static ssize_t possible_values_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
954 {
955 	struct tlmi_attr_setting *setting = to_tlmi_attr_setting(kobj);
956 
957 	if (!tlmi_priv.can_get_bios_selections)
958 		return -EOPNOTSUPP;
959 
960 	return sysfs_emit(buf, "%s\n", setting->possible_values);
961 }
962 
963 static ssize_t current_value_store(struct kobject *kobj,
964 		struct kobj_attribute *attr,
965 		const char *buf, size_t count)
966 {
967 	struct tlmi_attr_setting *setting = to_tlmi_attr_setting(kobj);
968 	char *set_str = NULL, *new_setting = NULL;
969 	char *auth_str = NULL;
970 	int ret;
971 
972 	if (!tlmi_priv.can_set_bios_settings)
973 		return -EOPNOTSUPP;
974 
975 	new_setting = kstrdup(buf, GFP_KERNEL);
976 	if (!new_setting)
977 		return -ENOMEM;
978 
979 	/* Strip out CR if one is present */
980 	strip_cr(new_setting);
981 
982 	/* Check if certificate authentication is enabled and active */
983 	if (tlmi_priv.certificate_support && tlmi_priv.pwd_admin->cert_installed) {
984 		if (!tlmi_priv.pwd_admin->signature || !tlmi_priv.pwd_admin->save_signature) {
985 			ret = -EINVAL;
986 			goto out;
987 		}
988 		set_str = kasprintf(GFP_KERNEL, "%s,%s,%s", setting->display_name,
989 					new_setting, tlmi_priv.pwd_admin->signature);
990 		if (!set_str) {
991 			ret = -ENOMEM;
992 			goto out;
993 		}
994 
995 		ret = tlmi_simple_call(LENOVO_SET_BIOS_SETTING_CERT_GUID, set_str);
996 		if (ret)
997 			goto out;
998 		ret = tlmi_simple_call(LENOVO_SAVE_BIOS_SETTING_CERT_GUID,
999 				tlmi_priv.pwd_admin->save_signature);
1000 		if (ret)
1001 			goto out;
1002 	} else { /* Non certiifcate based authentication */
1003 		if (tlmi_priv.pwd_admin->valid && tlmi_priv.pwd_admin->password[0]) {
1004 			auth_str = kasprintf(GFP_KERNEL, "%s,%s,%s;",
1005 					tlmi_priv.pwd_admin->password,
1006 					encoding_options[tlmi_priv.pwd_admin->encoding],
1007 					tlmi_priv.pwd_admin->kbdlang);
1008 			if (!auth_str) {
1009 				ret = -ENOMEM;
1010 				goto out;
1011 			}
1012 		}
1013 
1014 		if (auth_str)
1015 			set_str = kasprintf(GFP_KERNEL, "%s,%s,%s", setting->display_name,
1016 					new_setting, auth_str);
1017 		else
1018 			set_str = kasprintf(GFP_KERNEL, "%s,%s;", setting->display_name,
1019 					new_setting);
1020 		if (!set_str) {
1021 			ret = -ENOMEM;
1022 			goto out;
1023 		}
1024 
1025 		ret = tlmi_simple_call(LENOVO_SET_BIOS_SETTINGS_GUID, set_str);
1026 		if (ret)
1027 			goto out;
1028 
1029 		if (auth_str)
1030 			ret = tlmi_save_bios_settings(auth_str);
1031 		else
1032 			ret = tlmi_save_bios_settings("");
1033 	}
1034 	if (!ret && !tlmi_priv.pending_changes) {
1035 		tlmi_priv.pending_changes = true;
1036 		/* let userland know it may need to check reboot pending again */
1037 		kobject_uevent(&tlmi_priv.class_dev->kobj, KOBJ_CHANGE);
1038 	}
1039 out:
1040 	kfree(auth_str);
1041 	kfree(set_str);
1042 	kfree(new_setting);
1043 	return ret ?: count;
1044 }
1045 
1046 static struct kobj_attribute attr_displ_name = __ATTR_RO(display_name);
1047 
1048 static struct kobj_attribute attr_possible_values = __ATTR_RO(possible_values);
1049 
1050 static struct kobj_attribute attr_current_val = __ATTR_RW_MODE(current_value, 0600);
1051 
1052 static struct attribute *tlmi_attrs[] = {
1053 	&attr_displ_name.attr,
1054 	&attr_current_val.attr,
1055 	&attr_possible_values.attr,
1056 	NULL
1057 };
1058 
1059 static const struct attribute_group tlmi_attr_group = {
1060 	.attrs = tlmi_attrs,
1061 };
1062 
1063 static ssize_t tlmi_attr_show(struct kobject *kobj, struct attribute *attr,
1064 				    char *buf)
1065 {
1066 	struct kobj_attribute *kattr;
1067 
1068 	kattr = container_of(attr, struct kobj_attribute, attr);
1069 	if (kattr->show)
1070 		return kattr->show(kobj, kattr, buf);
1071 	return -EIO;
1072 }
1073 
1074 static ssize_t tlmi_attr_store(struct kobject *kobj, struct attribute *attr,
1075 				     const char *buf, size_t count)
1076 {
1077 	struct kobj_attribute *kattr;
1078 
1079 	kattr = container_of(attr, struct kobj_attribute, attr);
1080 	if (kattr->store)
1081 		return kattr->store(kobj, kattr, buf, count);
1082 	return -EIO;
1083 }
1084 
1085 static const struct sysfs_ops tlmi_kobj_sysfs_ops = {
1086 	.show	= tlmi_attr_show,
1087 	.store	= tlmi_attr_store,
1088 };
1089 
1090 static void tlmi_attr_setting_release(struct kobject *kobj)
1091 {
1092 	struct tlmi_attr_setting *setting = to_tlmi_attr_setting(kobj);
1093 
1094 	kfree(setting->possible_values);
1095 	kfree(setting);
1096 }
1097 
1098 static void tlmi_pwd_setting_release(struct kobject *kobj)
1099 {
1100 	struct tlmi_pwd_setting *setting = to_tlmi_pwd_setting(kobj);
1101 
1102 	kfree(setting);
1103 }
1104 
1105 static struct kobj_type tlmi_attr_setting_ktype = {
1106 	.release        = &tlmi_attr_setting_release,
1107 	.sysfs_ops	= &tlmi_kobj_sysfs_ops,
1108 };
1109 
1110 static struct kobj_type tlmi_pwd_setting_ktype = {
1111 	.release        = &tlmi_pwd_setting_release,
1112 	.sysfs_ops	= &tlmi_kobj_sysfs_ops,
1113 };
1114 
1115 static ssize_t pending_reboot_show(struct kobject *kobj, struct kobj_attribute *attr,
1116 				   char *buf)
1117 {
1118 	return sprintf(buf, "%d\n", tlmi_priv.pending_changes);
1119 }
1120 
1121 static struct kobj_attribute pending_reboot = __ATTR_RO(pending_reboot);
1122 
1123 /* ---- Debug interface--------------------------------------------------------- */
1124 static ssize_t debug_cmd_store(struct kobject *kobj, struct kobj_attribute *attr,
1125 				const char *buf, size_t count)
1126 {
1127 	char *set_str = NULL, *new_setting = NULL;
1128 	char *auth_str = NULL;
1129 	int ret;
1130 
1131 	if (!tlmi_priv.can_debug_cmd)
1132 		return -EOPNOTSUPP;
1133 
1134 	new_setting = kstrdup(buf, GFP_KERNEL);
1135 	if (!new_setting)
1136 		return -ENOMEM;
1137 
1138 	/* Strip out CR if one is present */
1139 	strip_cr(new_setting);
1140 
1141 	if (tlmi_priv.pwd_admin->valid && tlmi_priv.pwd_admin->password[0]) {
1142 		auth_str = kasprintf(GFP_KERNEL, "%s,%s,%s;",
1143 				tlmi_priv.pwd_admin->password,
1144 				encoding_options[tlmi_priv.pwd_admin->encoding],
1145 				tlmi_priv.pwd_admin->kbdlang);
1146 		if (!auth_str) {
1147 			ret = -ENOMEM;
1148 			goto out;
1149 		}
1150 	}
1151 
1152 	if (auth_str)
1153 		set_str = kasprintf(GFP_KERNEL, "%s,%s", new_setting, auth_str);
1154 	else
1155 		set_str = kasprintf(GFP_KERNEL, "%s;", new_setting);
1156 	if (!set_str) {
1157 		ret = -ENOMEM;
1158 		goto out;
1159 	}
1160 
1161 	ret = tlmi_simple_call(LENOVO_DEBUG_CMD_GUID, set_str);
1162 	if (ret)
1163 		goto out;
1164 
1165 	if (!ret && !tlmi_priv.pending_changes) {
1166 		tlmi_priv.pending_changes = true;
1167 		/* let userland know it may need to check reboot pending again */
1168 		kobject_uevent(&tlmi_priv.class_dev->kobj, KOBJ_CHANGE);
1169 	}
1170 out:
1171 	kfree(auth_str);
1172 	kfree(set_str);
1173 	kfree(new_setting);
1174 	return ret ?: count;
1175 }
1176 
1177 static struct kobj_attribute debug_cmd = __ATTR_WO(debug_cmd);
1178 
1179 /* ---- Initialisation --------------------------------------------------------- */
1180 static void tlmi_release_attr(void)
1181 {
1182 	int i;
1183 
1184 	/* Attribute structures */
1185 	for (i = 0; i < TLMI_SETTINGS_COUNT; i++) {
1186 		if (tlmi_priv.setting[i]) {
1187 			sysfs_remove_group(&tlmi_priv.setting[i]->kobj, &tlmi_attr_group);
1188 			kobject_put(&tlmi_priv.setting[i]->kobj);
1189 		}
1190 	}
1191 	sysfs_remove_file(&tlmi_priv.attribute_kset->kobj, &pending_reboot.attr);
1192 	if (tlmi_priv.can_debug_cmd && debug_support)
1193 		sysfs_remove_file(&tlmi_priv.attribute_kset->kobj, &debug_cmd.attr);
1194 
1195 	kset_unregister(tlmi_priv.attribute_kset);
1196 
1197 	/* Authentication structures */
1198 	sysfs_remove_group(&tlmi_priv.pwd_admin->kobj, &auth_attr_group);
1199 	kobject_put(&tlmi_priv.pwd_admin->kobj);
1200 	sysfs_remove_group(&tlmi_priv.pwd_power->kobj, &auth_attr_group);
1201 	kobject_put(&tlmi_priv.pwd_power->kobj);
1202 
1203 	if (tlmi_priv.opcode_support) {
1204 		sysfs_remove_group(&tlmi_priv.pwd_system->kobj, &auth_attr_group);
1205 		kobject_put(&tlmi_priv.pwd_system->kobj);
1206 		sysfs_remove_group(&tlmi_priv.pwd_hdd->kobj, &auth_attr_group);
1207 		kobject_put(&tlmi_priv.pwd_hdd->kobj);
1208 		sysfs_remove_group(&tlmi_priv.pwd_nvme->kobj, &auth_attr_group);
1209 		kobject_put(&tlmi_priv.pwd_nvme->kobj);
1210 	}
1211 
1212 	kset_unregister(tlmi_priv.authentication_kset);
1213 
1214 	/* Free up any saved certificates/signatures */
1215 	kfree(tlmi_priv.pwd_admin->certificate);
1216 	kfree(tlmi_priv.pwd_admin->signature);
1217 	kfree(tlmi_priv.pwd_admin->save_signature);
1218 }
1219 
1220 static int tlmi_sysfs_init(void)
1221 {
1222 	int i, ret;
1223 
1224 	ret = fw_attributes_class_get(&fw_attr_class);
1225 	if (ret)
1226 		return ret;
1227 
1228 	tlmi_priv.class_dev = device_create(fw_attr_class, NULL, MKDEV(0, 0),
1229 			NULL, "%s", "thinklmi");
1230 	if (IS_ERR(tlmi_priv.class_dev)) {
1231 		ret = PTR_ERR(tlmi_priv.class_dev);
1232 		goto fail_class_created;
1233 	}
1234 
1235 	tlmi_priv.attribute_kset = kset_create_and_add("attributes", NULL,
1236 			&tlmi_priv.class_dev->kobj);
1237 	if (!tlmi_priv.attribute_kset) {
1238 		ret = -ENOMEM;
1239 		goto fail_device_created;
1240 	}
1241 
1242 	for (i = 0; i < TLMI_SETTINGS_COUNT; i++) {
1243 		/* Check if index is a valid setting - skip if it isn't */
1244 		if (!tlmi_priv.setting[i])
1245 			continue;
1246 
1247 		/* check for duplicate or reserved values */
1248 		if (kset_find_obj(tlmi_priv.attribute_kset, tlmi_priv.setting[i]->display_name) ||
1249 		    !strcmp(tlmi_priv.setting[i]->display_name, "Reserved")) {
1250 			pr_debug("duplicate or reserved attribute name found - %s\n",
1251 				tlmi_priv.setting[i]->display_name);
1252 			kfree(tlmi_priv.setting[i]->possible_values);
1253 			kfree(tlmi_priv.setting[i]);
1254 			tlmi_priv.setting[i] = NULL;
1255 			continue;
1256 		}
1257 
1258 		/* Build attribute */
1259 		tlmi_priv.setting[i]->kobj.kset = tlmi_priv.attribute_kset;
1260 		ret = kobject_add(&tlmi_priv.setting[i]->kobj, NULL,
1261 				  "%s", tlmi_priv.setting[i]->display_name);
1262 		if (ret)
1263 			goto fail_create_attr;
1264 
1265 		ret = sysfs_create_group(&tlmi_priv.setting[i]->kobj, &tlmi_attr_group);
1266 		if (ret)
1267 			goto fail_create_attr;
1268 	}
1269 
1270 	ret = sysfs_create_file(&tlmi_priv.attribute_kset->kobj, &pending_reboot.attr);
1271 	if (ret)
1272 		goto fail_create_attr;
1273 
1274 	if (tlmi_priv.can_debug_cmd && debug_support) {
1275 		ret = sysfs_create_file(&tlmi_priv.attribute_kset->kobj, &debug_cmd.attr);
1276 		if (ret)
1277 			goto fail_create_attr;
1278 	}
1279 
1280 	/* Create authentication entries */
1281 	tlmi_priv.authentication_kset = kset_create_and_add("authentication", NULL,
1282 								&tlmi_priv.class_dev->kobj);
1283 	if (!tlmi_priv.authentication_kset) {
1284 		ret = -ENOMEM;
1285 		goto fail_create_attr;
1286 	}
1287 	tlmi_priv.pwd_admin->kobj.kset = tlmi_priv.authentication_kset;
1288 	ret = kobject_add(&tlmi_priv.pwd_admin->kobj, NULL, "%s", "Admin");
1289 	if (ret)
1290 		goto fail_create_attr;
1291 
1292 	ret = sysfs_create_group(&tlmi_priv.pwd_admin->kobj, &auth_attr_group);
1293 	if (ret)
1294 		goto fail_create_attr;
1295 
1296 	tlmi_priv.pwd_power->kobj.kset = tlmi_priv.authentication_kset;
1297 	ret = kobject_add(&tlmi_priv.pwd_power->kobj, NULL, "%s", "Power-on");
1298 	if (ret)
1299 		goto fail_create_attr;
1300 
1301 	ret = sysfs_create_group(&tlmi_priv.pwd_power->kobj, &auth_attr_group);
1302 	if (ret)
1303 		goto fail_create_attr;
1304 
1305 	if (tlmi_priv.opcode_support) {
1306 		tlmi_priv.pwd_system->kobj.kset = tlmi_priv.authentication_kset;
1307 		ret = kobject_add(&tlmi_priv.pwd_system->kobj, NULL, "%s", "System");
1308 		if (ret)
1309 			goto fail_create_attr;
1310 
1311 		ret = sysfs_create_group(&tlmi_priv.pwd_system->kobj, &auth_attr_group);
1312 		if (ret)
1313 			goto fail_create_attr;
1314 
1315 		tlmi_priv.pwd_hdd->kobj.kset = tlmi_priv.authentication_kset;
1316 		ret = kobject_add(&tlmi_priv.pwd_hdd->kobj, NULL, "%s", "HDD");
1317 		if (ret)
1318 			goto fail_create_attr;
1319 
1320 		ret = sysfs_create_group(&tlmi_priv.pwd_hdd->kobj, &auth_attr_group);
1321 		if (ret)
1322 			goto fail_create_attr;
1323 
1324 		tlmi_priv.pwd_nvme->kobj.kset = tlmi_priv.authentication_kset;
1325 		ret = kobject_add(&tlmi_priv.pwd_nvme->kobj, NULL, "%s", "NVMe");
1326 		if (ret)
1327 			goto fail_create_attr;
1328 
1329 		ret = sysfs_create_group(&tlmi_priv.pwd_nvme->kobj, &auth_attr_group);
1330 		if (ret)
1331 			goto fail_create_attr;
1332 	}
1333 
1334 	return ret;
1335 
1336 fail_create_attr:
1337 	tlmi_release_attr();
1338 fail_device_created:
1339 	device_destroy(fw_attr_class, MKDEV(0, 0));
1340 fail_class_created:
1341 	fw_attributes_class_put();
1342 	return ret;
1343 }
1344 
1345 /* ---- Base Driver -------------------------------------------------------- */
1346 static struct tlmi_pwd_setting *tlmi_create_auth(const char *pwd_type,
1347 			    const char *pwd_role)
1348 {
1349 	struct tlmi_pwd_setting *new_pwd;
1350 
1351 	new_pwd = kzalloc(sizeof(struct tlmi_pwd_setting), GFP_KERNEL);
1352 	if (!new_pwd)
1353 		return NULL;
1354 
1355 	strscpy(new_pwd->kbdlang, "us", TLMI_LANG_MAXLEN);
1356 	new_pwd->encoding = TLMI_ENCODING_ASCII;
1357 	new_pwd->pwd_type = pwd_type;
1358 	new_pwd->role = pwd_role;
1359 	new_pwd->minlen = tlmi_priv.pwdcfg.core.min_length;
1360 	new_pwd->maxlen = tlmi_priv.pwdcfg.core.max_length;
1361 	new_pwd->index = 0;
1362 
1363 	kobject_init(&new_pwd->kobj, &tlmi_pwd_setting_ktype);
1364 
1365 	return new_pwd;
1366 }
1367 
1368 static int tlmi_analyze(void)
1369 {
1370 	acpi_status status;
1371 	int i, ret;
1372 
1373 	if (wmi_has_guid(LENOVO_SET_BIOS_SETTINGS_GUID) &&
1374 	    wmi_has_guid(LENOVO_SAVE_BIOS_SETTINGS_GUID))
1375 		tlmi_priv.can_set_bios_settings = true;
1376 
1377 	if (wmi_has_guid(LENOVO_GET_BIOS_SELECTIONS_GUID))
1378 		tlmi_priv.can_get_bios_selections = true;
1379 
1380 	if (wmi_has_guid(LENOVO_SET_BIOS_PASSWORD_GUID))
1381 		tlmi_priv.can_set_bios_password = true;
1382 
1383 	if (wmi_has_guid(LENOVO_BIOS_PASSWORD_SETTINGS_GUID))
1384 		tlmi_priv.can_get_password_settings = true;
1385 
1386 	if (wmi_has_guid(LENOVO_DEBUG_CMD_GUID))
1387 		tlmi_priv.can_debug_cmd = true;
1388 
1389 	if (wmi_has_guid(LENOVO_OPCODE_IF_GUID))
1390 		tlmi_priv.opcode_support = true;
1391 
1392 	if (wmi_has_guid(LENOVO_SET_BIOS_CERT_GUID) &&
1393 		wmi_has_guid(LENOVO_SET_BIOS_SETTING_CERT_GUID) &&
1394 		wmi_has_guid(LENOVO_SAVE_BIOS_SETTING_CERT_GUID))
1395 		tlmi_priv.certificate_support = true;
1396 
1397 	/*
1398 	 * Try to find the number of valid settings of this machine
1399 	 * and use it to create sysfs attributes.
1400 	 */
1401 	for (i = 0; i < TLMI_SETTINGS_COUNT; ++i) {
1402 		struct tlmi_attr_setting *setting;
1403 		char *item = NULL;
1404 		char *p;
1405 
1406 		tlmi_priv.setting[i] = NULL;
1407 		status = tlmi_setting(i, &item, LENOVO_BIOS_SETTING_GUID);
1408 		if (ACPI_FAILURE(status))
1409 			break;
1410 		if (!item)
1411 			break;
1412 		if (!*item) {
1413 			kfree(item);
1414 			continue;
1415 		}
1416 
1417 		/* It is not allowed to have '/' for file name. Convert it into '\'. */
1418 		strreplace(item, '/', '\\');
1419 
1420 		/* Remove the value part */
1421 		p = strchrnul(item, ',');
1422 		*p = '\0';
1423 
1424 		/* Create a setting entry */
1425 		setting = kzalloc(sizeof(*setting), GFP_KERNEL);
1426 		if (!setting) {
1427 			ret = -ENOMEM;
1428 			kfree(item);
1429 			goto fail_clear_attr;
1430 		}
1431 		setting->index = i;
1432 		strscpy(setting->display_name, item, TLMI_SETTINGS_MAXLEN);
1433 		/* If BIOS selections supported, load those */
1434 		if (tlmi_priv.can_get_bios_selections) {
1435 			ret = tlmi_get_bios_selections(setting->display_name,
1436 					&setting->possible_values);
1437 			if (ret || !setting->possible_values)
1438 				pr_info("Error retrieving possible values for %d : %s\n",
1439 						i, setting->display_name);
1440 		}
1441 		kobject_init(&setting->kobj, &tlmi_attr_setting_ktype);
1442 		tlmi_priv.setting[i] = setting;
1443 		kfree(item);
1444 	}
1445 
1446 	/* Create password setting structure */
1447 	ret = tlmi_get_pwd_settings(&tlmi_priv.pwdcfg);
1448 	if (ret)
1449 		goto fail_clear_attr;
1450 
1451 	/* All failures below boil down to kmalloc failures */
1452 	ret = -ENOMEM;
1453 
1454 	tlmi_priv.pwd_admin = tlmi_create_auth("pap", "bios-admin");
1455 	if (!tlmi_priv.pwd_admin)
1456 		goto fail_clear_attr;
1457 
1458 	if (tlmi_priv.pwdcfg.core.password_state & TLMI_PAP_PWD)
1459 		tlmi_priv.pwd_admin->valid = true;
1460 
1461 	tlmi_priv.pwd_power = tlmi_create_auth("pop", "power-on");
1462 	if (!tlmi_priv.pwd_power)
1463 		goto fail_clear_attr;
1464 
1465 	if (tlmi_priv.pwdcfg.core.password_state & TLMI_POP_PWD)
1466 		tlmi_priv.pwd_power->valid = true;
1467 
1468 	if (tlmi_priv.opcode_support) {
1469 		tlmi_priv.pwd_system = tlmi_create_auth("sys", "system");
1470 		if (!tlmi_priv.pwd_system)
1471 			goto fail_clear_attr;
1472 
1473 		if (tlmi_priv.pwdcfg.core.password_state & TLMI_SYS_PWD)
1474 			tlmi_priv.pwd_system->valid = true;
1475 
1476 		tlmi_priv.pwd_hdd = tlmi_create_auth("hdd", "hdd");
1477 		if (!tlmi_priv.pwd_hdd)
1478 			goto fail_clear_attr;
1479 
1480 		tlmi_priv.pwd_nvme = tlmi_create_auth("nvm", "nvme");
1481 		if (!tlmi_priv.pwd_nvme)
1482 			goto fail_clear_attr;
1483 
1484 		if (tlmi_priv.pwdcfg.core.password_state & TLMI_HDD_PWD) {
1485 			/* Check if PWD is configured and set index to first drive found */
1486 			if (tlmi_priv.pwdcfg.ext.hdd_user_password ||
1487 					tlmi_priv.pwdcfg.ext.hdd_master_password) {
1488 				tlmi_priv.pwd_hdd->valid = true;
1489 				if (tlmi_priv.pwdcfg.ext.hdd_master_password)
1490 					tlmi_priv.pwd_hdd->index =
1491 						ffs(tlmi_priv.pwdcfg.ext.hdd_master_password) - 1;
1492 				else
1493 					tlmi_priv.pwd_hdd->index =
1494 						ffs(tlmi_priv.pwdcfg.ext.hdd_user_password) - 1;
1495 			}
1496 			if (tlmi_priv.pwdcfg.ext.nvme_user_password ||
1497 					tlmi_priv.pwdcfg.ext.nvme_master_password) {
1498 				tlmi_priv.pwd_nvme->valid = true;
1499 				if (tlmi_priv.pwdcfg.ext.nvme_master_password)
1500 					tlmi_priv.pwd_nvme->index =
1501 						ffs(tlmi_priv.pwdcfg.ext.nvme_master_password) - 1;
1502 				else
1503 					tlmi_priv.pwd_nvme->index =
1504 						ffs(tlmi_priv.pwdcfg.ext.nvme_user_password) - 1;
1505 			}
1506 		}
1507 	}
1508 
1509 	if (tlmi_priv.certificate_support &&
1510 		(tlmi_priv.pwdcfg.core.password_state & TLMI_CERT))
1511 		tlmi_priv.pwd_admin->cert_installed = true;
1512 
1513 	return 0;
1514 
1515 fail_clear_attr:
1516 	for (i = 0; i < TLMI_SETTINGS_COUNT; ++i) {
1517 		if (tlmi_priv.setting[i]) {
1518 			kfree(tlmi_priv.setting[i]->possible_values);
1519 			kfree(tlmi_priv.setting[i]);
1520 		}
1521 	}
1522 	kfree(tlmi_priv.pwd_admin);
1523 	kfree(tlmi_priv.pwd_power);
1524 	kfree(tlmi_priv.pwd_system);
1525 	kfree(tlmi_priv.pwd_hdd);
1526 	kfree(tlmi_priv.pwd_nvme);
1527 	return ret;
1528 }
1529 
1530 static void tlmi_remove(struct wmi_device *wdev)
1531 {
1532 	tlmi_release_attr();
1533 	device_destroy(fw_attr_class, MKDEV(0, 0));
1534 	fw_attributes_class_put();
1535 }
1536 
1537 static int tlmi_probe(struct wmi_device *wdev, const void *context)
1538 {
1539 	int ret;
1540 
1541 	ret = tlmi_analyze();
1542 	if (ret)
1543 		return ret;
1544 
1545 	return tlmi_sysfs_init();
1546 }
1547 
1548 static const struct wmi_device_id tlmi_id_table[] = {
1549 	{ .guid_string = LENOVO_BIOS_SETTING_GUID },
1550 	{ }
1551 };
1552 MODULE_DEVICE_TABLE(wmi, tlmi_id_table);
1553 
1554 static struct wmi_driver tlmi_driver = {
1555 	.driver = {
1556 		.name = "think-lmi",
1557 	},
1558 	.id_table = tlmi_id_table,
1559 	.probe = tlmi_probe,
1560 	.remove = tlmi_remove,
1561 };
1562 
1563 MODULE_AUTHOR("Sugumaran L <slacshiminar@lenovo.com>");
1564 MODULE_AUTHOR("Mark Pearson <markpearson@lenovo.com>");
1565 MODULE_AUTHOR("Corentin Chary <corentin.chary@gmail.com>");
1566 MODULE_DESCRIPTION("ThinkLMI Driver");
1567 MODULE_LICENSE("GPL");
1568 
1569 module_wmi_driver(tlmi_driver);
1570