// SPDX-License-Identifier: GPL-2.0-or-later /* * Think LMI BIOS configuration driver * * Copyright(C) 2019-2021 Lenovo * * Original code from Thinkpad-wmi project https://github.com/iksaif/thinkpad-wmi * Copyright(C) 2017 Corentin Chary * Distributed under the GPL-2.0 license */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include #include #include #include #include #include #include #include #include "firmware_attributes_class.h" #include "think-lmi.h" static bool debug_support; module_param(debug_support, bool, 0444); MODULE_PARM_DESC(debug_support, "Enable debug command support"); /* * Name: BiosSetting * Description: Get item name and settings for current LMI instance. * Type: Query * Returns: "Item,Value" * Example: "WakeOnLAN,Enable" */ #define LENOVO_BIOS_SETTING_GUID "51F5230E-9677-46CD-A1CF-C0B23EE34DB7" /* * Name: SetBiosSetting * Description: Change the BIOS setting to the desired value using the SetBiosSetting * class. To save the settings, use the SaveBiosSetting class. * BIOS settings and values are case sensitive. * After making changes to the BIOS settings, you must reboot the computer * before the changes will take effect. * Type: Method * Arguments: "Item,Value,Password,Encoding,KbdLang;" * Example: "WakeOnLAN,Disable,pa55w0rd,ascii,us;" */ #define LENOVO_SET_BIOS_SETTINGS_GUID "98479A64-33F5-4E33-A707-8E251EBBC3A1" /* * Name: SaveBiosSettings * Description: Save any pending changes in settings. * Type: Method * Arguments: "Password,Encoding,KbdLang;" * Example: "pa55w0rd,ascii,us;" */ #define LENOVO_SAVE_BIOS_SETTINGS_GUID "6A4B54EF-A5ED-4D33-9455-B0D9B48DF4B3" /* * Name: BiosPasswordSettings * Description: Return BIOS Password settings * Type: Query * Returns: PasswordMode, PasswordState, MinLength, MaxLength, * SupportedEncoding, SupportedKeyboard */ #define LENOVO_BIOS_PASSWORD_SETTINGS_GUID "8ADB159E-1E32-455C-BC93-308A7ED98246" /* * Name: SetBiosPassword * Description: Change a specific password. * - BIOS settings cannot be changed at the same boot as power-on * passwords (POP) and hard disk passwords (HDP). If you want to change * BIOS settings and POP or HDP, you must reboot the system after changing * one of them. * - A password cannot be set using this method when one does not already * exist. Passwords can only be updated or cleared. * Type: Method * Arguments: "PasswordType,CurrentPassword,NewPassword,Encoding,KbdLang;" * Example: "pop,pa55w0rd,newpa55w0rd,ascii,us;” */ #define LENOVO_SET_BIOS_PASSWORD_GUID "2651D9FD-911C-4B69-B94E-D0DED5963BD7" /* * Name: GetBiosSelections * Description: Return a list of valid settings for a given item. * Type: Method * Arguments: "Item" * Returns: "Value1,Value2,Value3,..." * Example: * -> "FlashOverLAN" * <- "Enabled,Disabled" */ #define LENOVO_GET_BIOS_SELECTIONS_GUID "7364651A-132F-4FE7-ADAA-40C6C7EE2E3B" /* * Name: DebugCmd * Description: Debug entry method for entering debug commands to the BIOS */ #define LENOVO_DEBUG_CMD_GUID "7FF47003-3B6C-4E5E-A227-E979824A85D1" /* * Name: OpcodeIF * Description: Opcode interface which provides the ability to set multiple * parameters and then trigger an action with a final command. * This is particularly useful for simplifying setting passwords. * With this support comes the ability to set System, HDD and NVMe * passwords. * This is currently available on ThinkCenter and ThinkStations platforms */ #define LENOVO_OPCODE_IF_GUID "DFDDEF2C-57D4-48ce-B196-0FB787D90836" /* * Name: SetBiosCert * Description: Install BIOS certificate. * Type: Method * Arguments: "Certificate,Password" * You must reboot the computer before the changes will take effect. */ #define LENOVO_SET_BIOS_CERT_GUID "26861C9F-47E9-44C4-BD8B-DFE7FA2610FE" /* * Name: UpdateBiosCert * Description: Update BIOS certificate. * Type: Method * Format: "Certificate,Signature" * You must reboot the computer before the changes will take effect. */ #define LENOVO_UPDATE_BIOS_CERT_GUID "9AA3180A-9750-41F7-B9F7-D5D3B1BAC3CE" /* * Name: ClearBiosCert * Description: Uninstall BIOS certificate. * Type: Method * Format: "Serial,Signature" * You must reboot the computer before the changes will take effect. */ #define LENOVO_CLEAR_BIOS_CERT_GUID "B2BC39A7-78DD-4D71-B059-A510DEC44890" /* * Name: CertToPassword * Description: Switch from certificate to password authentication. * Type: Method * Format: "Password,Signature" * You must reboot the computer before the changes will take effect. */ #define LENOVO_CERT_TO_PASSWORD_GUID "0DE8590D-5510-4044-9621-77C227F5A70D" /* * Name: SetBiosSettingCert * Description: Set attribute using certificate authentication. * Type: Method * Format: "Item,Value,Signature" */ #define LENOVO_SET_BIOS_SETTING_CERT_GUID "34A008CC-D205-4B62-9E67-31DFA8B90003" /* * Name: SaveBiosSettingCert * Description: Save any pending changes in settings. * Type: Method * Format: "Signature" */ #define LENOVO_SAVE_BIOS_SETTING_CERT_GUID "C050FB9D-DF5F-4606-B066-9EFC401B2551" /* * Name: CertThumbprint * Description: Display Certificate thumbprints * Type: Query * Returns: MD5, SHA1 & SHA256 thumbprints */ #define LENOVO_CERT_THUMBPRINT_GUID "C59119ED-1C0D-4806-A8E9-59AA318176C4" #define TLMI_POP_PWD (1 << 0) #define TLMI_PAP_PWD (1 << 1) #define TLMI_HDD_PWD (1 << 2) #define TLMI_SMP_PWD (1 << 6) /* System Management */ #define TLMI_CERT (1 << 7) #define to_tlmi_pwd_setting(kobj) container_of(kobj, struct tlmi_pwd_setting, kobj) #define to_tlmi_attr_setting(kobj) container_of(kobj, struct tlmi_attr_setting, kobj) static const struct tlmi_err_codes tlmi_errs[] = { {"Success", 0}, {"Not Supported", -EOPNOTSUPP}, {"Invalid Parameter", -EINVAL}, {"Access Denied", -EACCES}, {"System Busy", -EBUSY}, }; static const char * const encoding_options[] = { [TLMI_ENCODING_ASCII] = "ascii", [TLMI_ENCODING_SCANCODE] = "scancode", }; static const char * const level_options[] = { [TLMI_LEVEL_USER] = "user", [TLMI_LEVEL_MASTER] = "master", }; static struct think_lmi tlmi_priv; static struct class *fw_attr_class; static DEFINE_MUTEX(tlmi_mutex); /* ------ Utility functions ------------*/ /* Strip out CR if one is present */ static void strip_cr(char *str) { char *p = strchrnul(str, '\n'); *p = '\0'; } /* Convert BIOS WMI error string to suitable error code */ static int tlmi_errstr_to_err(const char *errstr) { int i; for (i = 0; i < sizeof(tlmi_errs)/sizeof(struct tlmi_err_codes); i++) { if (!strcmp(tlmi_errs[i].err_str, errstr)) return tlmi_errs[i].err_code; } return -EPERM; } /* Extract error string from WMI return buffer */ static int tlmi_extract_error(const struct acpi_buffer *output) { const union acpi_object *obj; obj = output->pointer; if (!obj) return -ENOMEM; if (obj->type != ACPI_TYPE_STRING || !obj->string.pointer) return -EIO; return tlmi_errstr_to_err(obj->string.pointer); } /* Utility function to execute WMI call to BIOS */ static int tlmi_simple_call(const char *guid, const char *arg) { const struct acpi_buffer input = { strlen(arg), (char *)arg }; struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL }; acpi_status status; int i, err; /* * Duplicated call required to match BIOS workaround for behavior * seen when WMI accessed via scripting on other OS. */ for (i = 0; i < 2; i++) { /* (re)initialize output buffer to default state */ output.length = ACPI_ALLOCATE_BUFFER; output.pointer = NULL; status = wmi_evaluate_method(guid, 0, 0, &input, &output); if (ACPI_FAILURE(status)) { kfree(output.pointer); return -EIO; } err = tlmi_extract_error(&output); kfree(output.pointer); if (err) return err; } return 0; } /* Extract output string from WMI return buffer */ static int tlmi_extract_output_string(const struct acpi_buffer *output, char **string) { const union acpi_object *obj; char *s; obj = output->pointer; if (!obj) return -ENOMEM; if (obj->type != ACPI_TYPE_STRING || !obj->string.pointer) return -EIO; s = kstrdup(obj->string.pointer, GFP_KERNEL); if (!s) return -ENOMEM; *string = s; return 0; } /* ------ Core interface functions ------------*/ /* Get password settings from BIOS */ static int tlmi_get_pwd_settings(struct tlmi_pwdcfg *pwdcfg) { struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL }; const union acpi_object *obj; acpi_status status; int copy_size; if (!tlmi_priv.can_get_password_settings) return -EOPNOTSUPP; status = wmi_query_block(LENOVO_BIOS_PASSWORD_SETTINGS_GUID, 0, &output); if (ACPI_FAILURE(status)) return -EIO; obj = output.pointer; if (!obj) return -ENOMEM; if (obj->type != ACPI_TYPE_BUFFER || !obj->buffer.pointer) { kfree(obj); return -EIO; } /* * The size of thinkpad_wmi_pcfg on ThinkStation is larger than ThinkPad. * To make the driver compatible on different brands, we permit it to get * the data in below case. * Settings must have at minimum the core fields available */ if (obj->buffer.length < sizeof(struct tlmi_pwdcfg_core)) { pr_warn("Unknown pwdcfg buffer length %d\n", obj->buffer.length); kfree(obj); return -EIO; } copy_size = obj->buffer.length < sizeof(struct tlmi_pwdcfg) ? obj->buffer.length : sizeof(struct tlmi_pwdcfg); memcpy(pwdcfg, obj->buffer.pointer, copy_size); kfree(obj); if (WARN_ON(pwdcfg->core.max_length >= TLMI_PWD_BUFSIZE)) pwdcfg->core.max_length = TLMI_PWD_BUFSIZE - 1; return 0; } static int tlmi_save_bios_settings(const char *password) { return tlmi_simple_call(LENOVO_SAVE_BIOS_SETTINGS_GUID, password); } static int tlmi_opcode_setting(char *setting, const char *value) { char *opcode_str; int ret; opcode_str = kasprintf(GFP_KERNEL, "%s:%s;", setting, value); if (!opcode_str) return -ENOMEM; ret = tlmi_simple_call(LENOVO_OPCODE_IF_GUID, opcode_str); kfree(opcode_str); return ret; } static int tlmi_setting(int item, char **value, const char *guid_string) { struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL }; acpi_status status; int ret; status = wmi_query_block(guid_string, item, &output); if (ACPI_FAILURE(status)) { kfree(output.pointer); return -EIO; } ret = tlmi_extract_output_string(&output, value); kfree(output.pointer); return ret; } static int tlmi_get_bios_selections(const char *item, char **value) { const struct acpi_buffer input = { strlen(item), (char *)item }; struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL }; acpi_status status; int ret; status = wmi_evaluate_method(LENOVO_GET_BIOS_SELECTIONS_GUID, 0, 0, &input, &output); if (ACPI_FAILURE(status)) { kfree(output.pointer); return -EIO; } ret = tlmi_extract_output_string(&output, value); kfree(output.pointer); return ret; } /* ---- Authentication sysfs --------------------------------------------------------- */ static ssize_t is_enabled_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { struct tlmi_pwd_setting *setting = to_tlmi_pwd_setting(kobj); return sysfs_emit(buf, "%d\n", setting->valid); } static struct kobj_attribute auth_is_pass_set = __ATTR_RO(is_enabled); static ssize_t current_password_store(struct kobject *kobj, struct kobj_attribute *attr, const char *buf, size_t count) { struct tlmi_pwd_setting *setting = to_tlmi_pwd_setting(kobj); size_t pwdlen; pwdlen = strlen(buf); /* pwdlen == 0 is allowed to clear the password */ if (pwdlen && ((pwdlen < setting->minlen) || (pwdlen > setting->maxlen))) return -EINVAL; strscpy(setting->password, buf, setting->maxlen); /* Strip out CR if one is present, setting password won't work if it is present */ strip_cr(setting->password); return count; } static struct kobj_attribute auth_current_password = __ATTR_WO(current_password); static ssize_t new_password_store(struct kobject *kobj, struct kobj_attribute *attr, const char *buf, size_t count) { struct tlmi_pwd_setting *setting = to_tlmi_pwd_setting(kobj); char *auth_str, *new_pwd; size_t pwdlen; int ret; if (!capable(CAP_SYS_ADMIN)) return -EPERM; if (!tlmi_priv.can_set_bios_password) return -EOPNOTSUPP; new_pwd = kstrdup(buf, GFP_KERNEL); if (!new_pwd) return -ENOMEM; /* Strip out CR if one is present, setting password won't work if it is present */ strip_cr(new_pwd); /* Use lock in case multiple WMI operations needed */ mutex_lock(&tlmi_mutex); pwdlen = strlen(new_pwd); /* pwdlen == 0 is allowed to clear the password */ if (pwdlen && ((pwdlen < setting->minlen) || (pwdlen > setting->maxlen))) { ret = -EINVAL; goto out; } /* If opcode support is present use that interface */ if (tlmi_priv.opcode_support) { char pwd_type[8]; /* Special handling required for HDD and NVMe passwords */ if (setting == tlmi_priv.pwd_hdd) { if (setting->level == TLMI_LEVEL_USER) sprintf(pwd_type, "uhdp%d", setting->index); else sprintf(pwd_type, "mhdp%d", setting->index); } else if (setting == tlmi_priv.pwd_nvme) { if (setting->level == TLMI_LEVEL_USER) sprintf(pwd_type, "udrp%d", setting->index); else sprintf(pwd_type, "adrp%d", setting->index); } else { sprintf(pwd_type, "%s", setting->pwd_type); } ret = tlmi_opcode_setting("WmiOpcodePasswordType", pwd_type); if (ret) goto out; if (tlmi_priv.pwd_admin->valid) { ret = tlmi_opcode_setting("WmiOpcodePasswordAdmin", tlmi_priv.pwd_admin->password); if (ret) goto out; } ret = tlmi_opcode_setting("WmiOpcodePasswordCurrent01", setting->password); if (ret) goto out; ret = tlmi_opcode_setting("WmiOpcodePasswordNew01", new_pwd); if (ret) goto out; ret = tlmi_simple_call(LENOVO_OPCODE_IF_GUID, "WmiOpcodePasswordSetUpdate;"); } else { /* Format: 'PasswordType,CurrentPw,NewPw,Encoding,KbdLang;' */ auth_str = kasprintf(GFP_KERNEL, "%s,%s,%s,%s,%s;", setting->pwd_type, setting->password, new_pwd, encoding_options[setting->encoding], setting->kbdlang); if (!auth_str) { ret = -ENOMEM; goto out; } ret = tlmi_simple_call(LENOVO_SET_BIOS_PASSWORD_GUID, auth_str); kfree(auth_str); } out: mutex_unlock(&tlmi_mutex); kfree(new_pwd); return ret ?: count; } static struct kobj_attribute auth_new_password = __ATTR_WO(new_password); static ssize_t min_password_length_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { struct tlmi_pwd_setting *setting = to_tlmi_pwd_setting(kobj); return sysfs_emit(buf, "%d\n", setting->minlen); } static struct kobj_attribute auth_min_pass_length = __ATTR_RO(min_password_length); static ssize_t max_password_length_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { struct tlmi_pwd_setting *setting = to_tlmi_pwd_setting(kobj); return sysfs_emit(buf, "%d\n", setting->maxlen); } static struct kobj_attribute auth_max_pass_length = __ATTR_RO(max_password_length); static ssize_t mechanism_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { return sysfs_emit(buf, "password\n"); } static struct kobj_attribute auth_mechanism = __ATTR_RO(mechanism); static ssize_t encoding_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { struct tlmi_pwd_setting *setting = to_tlmi_pwd_setting(kobj); return sysfs_emit(buf, "%s\n", encoding_options[setting->encoding]); } static ssize_t encoding_store(struct kobject *kobj, struct kobj_attribute *attr, const char *buf, size_t count) { struct tlmi_pwd_setting *setting = to_tlmi_pwd_setting(kobj); int i; /* Scan for a matching profile */ i = sysfs_match_string(encoding_options, buf); if (i < 0) return -EINVAL; setting->encoding = i; return count; } static struct kobj_attribute auth_encoding = __ATTR_RW(encoding); static ssize_t kbdlang_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { struct tlmi_pwd_setting *setting = to_tlmi_pwd_setting(kobj); return sysfs_emit(buf, "%s\n", setting->kbdlang); } static ssize_t kbdlang_store(struct kobject *kobj, struct kobj_attribute *attr, const char *buf, size_t count) { struct tlmi_pwd_setting *setting = to_tlmi_pwd_setting(kobj); int length; /* Calculate length till '\n' or terminating 0 */ length = strchrnul(buf, '\n') - buf; if (!length || length >= TLMI_LANG_MAXLEN) return -EINVAL; memcpy(setting->kbdlang, buf, length); setting->kbdlang[length] = '\0'; return count; } static struct kobj_attribute auth_kbdlang = __ATTR_RW(kbdlang); static ssize_t role_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { struct tlmi_pwd_setting *setting = to_tlmi_pwd_setting(kobj); return sysfs_emit(buf, "%s\n", setting->role); } static struct kobj_attribute auth_role = __ATTR_RO(role); static ssize_t index_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { struct tlmi_pwd_setting *setting = to_tlmi_pwd_setting(kobj); return sysfs_emit(buf, "%d\n", setting->index); } static ssize_t index_store(struct kobject *kobj, struct kobj_attribute *attr, const char *buf, size_t count) { struct tlmi_pwd_setting *setting = to_tlmi_pwd_setting(kobj); int err, val; err = kstrtoint(buf, 10, &val); if (err < 0) return err; if (val < 0 || val > TLMI_INDEX_MAX) return -EINVAL; setting->index = val; return count; } static struct kobj_attribute auth_index = __ATTR_RW(index); static ssize_t level_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { struct tlmi_pwd_setting *setting = to_tlmi_pwd_setting(kobj); return sysfs_emit(buf, "%s\n", level_options[setting->level]); } static ssize_t level_store(struct kobject *kobj, struct kobj_attribute *attr, const char *buf, size_t count) { struct tlmi_pwd_setting *setting = to_tlmi_pwd_setting(kobj); int i; /* Scan for a matching profile */ i = sysfs_match_string(level_options, buf); if (i < 0) return -EINVAL; setting->level = i; return count; } static struct kobj_attribute auth_level = __ATTR_RW(level); static ssize_t cert_thumbprint(char *buf, const char *arg, int count) { const struct acpi_buffer input = { strlen(arg), (char *)arg }; struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL }; const union acpi_object *obj; acpi_status status; status = wmi_evaluate_method(LENOVO_CERT_THUMBPRINT_GUID, 0, 0, &input, &output); if (ACPI_FAILURE(status)) { kfree(output.pointer); return -EIO; } obj = output.pointer; if (!obj) return -ENOMEM; if (obj->type != ACPI_TYPE_STRING || !obj->string.pointer) { kfree(output.pointer); return -EIO; } count += sysfs_emit_at(buf, count, "%s : %s\n", arg, (char *)obj->string.pointer); kfree(output.pointer); return count; } static ssize_t certificate_thumbprint_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { struct tlmi_pwd_setting *setting = to_tlmi_pwd_setting(kobj); int count = 0; if (!tlmi_priv.certificate_support || !setting->cert_installed) return -EOPNOTSUPP; count += cert_thumbprint(buf, "Md5", count); count += cert_thumbprint(buf, "Sha1", count); count += cert_thumbprint(buf, "Sha256", count); return count; } static struct kobj_attribute auth_cert_thumb = __ATTR_RO(certificate_thumbprint); static ssize_t cert_to_password_store(struct kobject *kobj, struct kobj_attribute *attr, const char *buf, size_t count) { struct tlmi_pwd_setting *setting = to_tlmi_pwd_setting(kobj); char *auth_str, *passwd; int ret; if (!capable(CAP_SYS_ADMIN)) return -EPERM; if (!tlmi_priv.certificate_support) return -EOPNOTSUPP; if (!setting->cert_installed) return -EINVAL; if (!setting->signature || !setting->signature[0]) return -EACCES; passwd = kstrdup(buf, GFP_KERNEL); if (!passwd) return -ENOMEM; /* Strip out CR if one is present */ strip_cr(passwd); /* Format: 'Password,Signature' */ auth_str = kasprintf(GFP_KERNEL, "%s,%s", passwd, setting->signature); if (!auth_str) { kfree_sensitive(passwd); return -ENOMEM; } ret = tlmi_simple_call(LENOVO_CERT_TO_PASSWORD_GUID, auth_str); kfree(auth_str); kfree_sensitive(passwd); return ret ?: count; } static struct kobj_attribute auth_cert_to_password = __ATTR_WO(cert_to_password); static ssize_t certificate_store(struct kobject *kobj, struct kobj_attribute *attr, const char *buf, size_t count) { struct tlmi_pwd_setting *setting = to_tlmi_pwd_setting(kobj); char *auth_str, *new_cert; char *guid; int ret; if (!capable(CAP_SYS_ADMIN)) return -EPERM; if (!tlmi_priv.certificate_support) return -EOPNOTSUPP; /* If empty then clear installed certificate */ if ((buf[0] == '\0') || (buf[0] == '\n')) { /* Clear installed certificate */ /* Check that signature is set */ if (!setting->signature || !setting->signature[0]) return -EACCES; /* Format: 'serial#, signature' */ auth_str = kasprintf(GFP_KERNEL, "%s,%s", dmi_get_system_info(DMI_PRODUCT_SERIAL), setting->signature); if (!auth_str) return -ENOMEM; ret = tlmi_simple_call(LENOVO_CLEAR_BIOS_CERT_GUID, auth_str); kfree(auth_str); return ret ?: count; } new_cert = kstrdup(buf, GFP_KERNEL); if (!new_cert) return -ENOMEM; /* Strip out CR if one is present */ strip_cr(new_cert); if (setting->cert_installed) { /* Certificate is installed so this is an update */ if (!setting->signature || !setting->signature[0]) { kfree(new_cert); return -EACCES; } guid = LENOVO_UPDATE_BIOS_CERT_GUID; /* Format: 'Certificate,Signature' */ auth_str = kasprintf(GFP_KERNEL, "%s,%s", new_cert, setting->signature); } else { /* This is a fresh install */ if (!setting->valid || !setting->password[0]) { kfree(new_cert); return -EACCES; } guid = LENOVO_SET_BIOS_CERT_GUID; /* Format: 'Certificate,Admin-password' */ auth_str = kasprintf(GFP_KERNEL, "%s,%s", new_cert, setting->password); } kfree(new_cert); if (!auth_str) return -ENOMEM; ret = tlmi_simple_call(guid, auth_str); kfree(auth_str); return ret ?: count; } static struct kobj_attribute auth_certificate = __ATTR_WO(certificate); static ssize_t signature_store(struct kobject *kobj, struct kobj_attribute *attr, const char *buf, size_t count) { struct tlmi_pwd_setting *setting = to_tlmi_pwd_setting(kobj); char *new_signature; if (!capable(CAP_SYS_ADMIN)) return -EPERM; if (!tlmi_priv.certificate_support) return -EOPNOTSUPP; new_signature = kstrdup(buf, GFP_KERNEL); if (!new_signature) return -ENOMEM; /* Strip out CR if one is present */ strip_cr(new_signature); /* Free any previous signature */ kfree(setting->signature); setting->signature = new_signature; return count; } static struct kobj_attribute auth_signature = __ATTR_WO(signature); static ssize_t save_signature_store(struct kobject *kobj, struct kobj_attribute *attr, const char *buf, size_t count) { struct tlmi_pwd_setting *setting = to_tlmi_pwd_setting(kobj); char *new_signature; if (!capable(CAP_SYS_ADMIN)) return -EPERM; if (!tlmi_priv.certificate_support) return -EOPNOTSUPP; new_signature = kstrdup(buf, GFP_KERNEL); if (!new_signature) return -ENOMEM; /* Strip out CR if one is present */ strip_cr(new_signature); /* Free any previous signature */ kfree(setting->save_signature); setting->save_signature = new_signature; return count; } static struct kobj_attribute auth_save_signature = __ATTR_WO(save_signature); static umode_t auth_attr_is_visible(struct kobject *kobj, struct attribute *attr, int n) { struct tlmi_pwd_setting *setting = to_tlmi_pwd_setting(kobj); /* We only want to display level and index settings on HDD/NVMe */ if ((attr == (struct attribute *)&auth_index) || (attr == (struct attribute *)&auth_level)) { if ((setting == tlmi_priv.pwd_hdd) || (setting == tlmi_priv.pwd_nvme)) return attr->mode; return 0; } /* We only display certificates on Admin account, if supported */ if ((attr == (struct attribute *)&auth_certificate) || (attr == (struct attribute *)&auth_signature) || (attr == (struct attribute *)&auth_save_signature) || (attr == (struct attribute *)&auth_cert_thumb) || (attr == (struct attribute *)&auth_cert_to_password)) { if ((setting == tlmi_priv.pwd_admin) && tlmi_priv.certificate_support) return attr->mode; return 0; } return attr->mode; } static struct attribute *auth_attrs[] = { &auth_is_pass_set.attr, &auth_min_pass_length.attr, &auth_max_pass_length.attr, &auth_current_password.attr, &auth_new_password.attr, &auth_role.attr, &auth_mechanism.attr, &auth_encoding.attr, &auth_kbdlang.attr, &auth_index.attr, &auth_level.attr, &auth_certificate.attr, &auth_signature.attr, &auth_save_signature.attr, &auth_cert_thumb.attr, &auth_cert_to_password.attr, NULL }; static const struct attribute_group auth_attr_group = { .is_visible = auth_attr_is_visible, .attrs = auth_attrs, }; /* ---- Attributes sysfs --------------------------------------------------------- */ static ssize_t display_name_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { struct tlmi_attr_setting *setting = to_tlmi_attr_setting(kobj); return sysfs_emit(buf, "%s\n", setting->display_name); } static ssize_t current_value_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { struct tlmi_attr_setting *setting = to_tlmi_attr_setting(kobj); char *item, *value, *p; int ret; ret = tlmi_setting(setting->index, &item, LENOVO_BIOS_SETTING_GUID); if (ret) return ret; /* validate and split from `item,value` -> `value` */ value = strpbrk(item, ","); if (!value || value == item || !strlen(value + 1)) ret = -EINVAL; else { /* On Workstations remove the Options part after the value */ p = strchrnul(value, ';'); *p = '\0'; ret = sysfs_emit(buf, "%s\n", value + 1); } kfree(item); return ret; } static ssize_t possible_values_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { struct tlmi_attr_setting *setting = to_tlmi_attr_setting(kobj); return sysfs_emit(buf, "%s\n", setting->possible_values); } static ssize_t type_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { struct tlmi_attr_setting *setting = to_tlmi_attr_setting(kobj); if (setting->possible_values) { /* Figure out what setting type is as BIOS does not return this */ if (strchr(setting->possible_values, ';')) return sysfs_emit(buf, "enumeration\n"); } /* Anything else is going to be a string */ return sysfs_emit(buf, "string\n"); } static ssize_t current_value_store(struct kobject *kobj, struct kobj_attribute *attr, const char *buf, size_t count) { struct tlmi_attr_setting *setting = to_tlmi_attr_setting(kobj); char *set_str = NULL, *new_setting = NULL; char *auth_str = NULL; int ret; if (!tlmi_priv.can_set_bios_settings) return -EOPNOTSUPP; new_setting = kstrdup(buf, GFP_KERNEL); if (!new_setting) return -ENOMEM; /* Strip out CR if one is present */ strip_cr(new_setting); /* Use lock in case multiple WMI operations needed */ mutex_lock(&tlmi_mutex); /* Check if certificate authentication is enabled and active */ if (tlmi_priv.certificate_support && tlmi_priv.pwd_admin->cert_installed) { if (!tlmi_priv.pwd_admin->signature || !tlmi_priv.pwd_admin->save_signature) { ret = -EINVAL; goto out; } set_str = kasprintf(GFP_KERNEL, "%s,%s,%s", setting->display_name, new_setting, tlmi_priv.pwd_admin->signature); if (!set_str) { ret = -ENOMEM; goto out; } ret = tlmi_simple_call(LENOVO_SET_BIOS_SETTING_CERT_GUID, set_str); if (ret) goto out; ret = tlmi_simple_call(LENOVO_SAVE_BIOS_SETTING_CERT_GUID, tlmi_priv.pwd_admin->save_signature); if (ret) goto out; } else { /* Non certiifcate based authentication */ if (tlmi_priv.pwd_admin->valid && tlmi_priv.pwd_admin->password[0]) { auth_str = kasprintf(GFP_KERNEL, "%s,%s,%s;", tlmi_priv.pwd_admin->password, encoding_options[tlmi_priv.pwd_admin->encoding], tlmi_priv.pwd_admin->kbdlang); if (!auth_str) { ret = -ENOMEM; goto out; } } if (auth_str) set_str = kasprintf(GFP_KERNEL, "%s,%s,%s", setting->display_name, new_setting, auth_str); else set_str = kasprintf(GFP_KERNEL, "%s,%s;", setting->display_name, new_setting); if (!set_str) { ret = -ENOMEM; goto out; } ret = tlmi_simple_call(LENOVO_SET_BIOS_SETTINGS_GUID, set_str); if (ret) goto out; if (auth_str) ret = tlmi_save_bios_settings(auth_str); else ret = tlmi_save_bios_settings(""); } if (!ret && !tlmi_priv.pending_changes) { tlmi_priv.pending_changes = true; /* let userland know it may need to check reboot pending again */ kobject_uevent(&tlmi_priv.class_dev->kobj, KOBJ_CHANGE); } out: mutex_unlock(&tlmi_mutex); kfree(auth_str); kfree(set_str); kfree(new_setting); return ret ?: count; } static struct kobj_attribute attr_displ_name = __ATTR_RO(display_name); static struct kobj_attribute attr_possible_values = __ATTR_RO(possible_values); static struct kobj_attribute attr_current_val = __ATTR_RW_MODE(current_value, 0600); static struct kobj_attribute attr_type = __ATTR_RO(type); static umode_t attr_is_visible(struct kobject *kobj, struct attribute *attr, int n) { struct tlmi_attr_setting *setting = to_tlmi_attr_setting(kobj); /* We don't want to display possible_values attributes if not available */ if ((attr == &attr_possible_values.attr) && (!setting->possible_values)) return 0; return attr->mode; } static struct attribute *tlmi_attrs[] = { &attr_displ_name.attr, &attr_current_val.attr, &attr_possible_values.attr, &attr_type.attr, NULL }; static const struct attribute_group tlmi_attr_group = { .is_visible = attr_is_visible, .attrs = tlmi_attrs, }; static ssize_t tlmi_attr_show(struct kobject *kobj, struct attribute *attr, char *buf) { struct kobj_attribute *kattr; kattr = container_of(attr, struct kobj_attribute, attr); if (kattr->show) return kattr->show(kobj, kattr, buf); return -EIO; } static ssize_t tlmi_attr_store(struct kobject *kobj, struct attribute *attr, const char *buf, size_t count) { struct kobj_attribute *kattr; kattr = container_of(attr, struct kobj_attribute, attr); if (kattr->store) return kattr->store(kobj, kattr, buf, count); return -EIO; } static const struct sysfs_ops tlmi_kobj_sysfs_ops = { .show = tlmi_attr_show, .store = tlmi_attr_store, }; static void tlmi_attr_setting_release(struct kobject *kobj) { struct tlmi_attr_setting *setting = to_tlmi_attr_setting(kobj); kfree(setting->possible_values); kfree(setting); } static void tlmi_pwd_setting_release(struct kobject *kobj) { struct tlmi_pwd_setting *setting = to_tlmi_pwd_setting(kobj); kfree(setting); } static struct kobj_type tlmi_attr_setting_ktype = { .release = &tlmi_attr_setting_release, .sysfs_ops = &tlmi_kobj_sysfs_ops, }; static struct kobj_type tlmi_pwd_setting_ktype = { .release = &tlmi_pwd_setting_release, .sysfs_ops = &tlmi_kobj_sysfs_ops, }; static ssize_t pending_reboot_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { return sprintf(buf, "%d\n", tlmi_priv.pending_changes); } static struct kobj_attribute pending_reboot = __ATTR_RO(pending_reboot); /* ---- Debug interface--------------------------------------------------------- */ static ssize_t debug_cmd_store(struct kobject *kobj, struct kobj_attribute *attr, const char *buf, size_t count) { char *set_str = NULL, *new_setting = NULL; char *auth_str = NULL; int ret; if (!tlmi_priv.can_debug_cmd) return -EOPNOTSUPP; new_setting = kstrdup(buf, GFP_KERNEL); if (!new_setting) return -ENOMEM; /* Strip out CR if one is present */ strip_cr(new_setting); if (tlmi_priv.pwd_admin->valid && tlmi_priv.pwd_admin->password[0]) { auth_str = kasprintf(GFP_KERNEL, "%s,%s,%s;", tlmi_priv.pwd_admin->password, encoding_options[tlmi_priv.pwd_admin->encoding], tlmi_priv.pwd_admin->kbdlang); if (!auth_str) { ret = -ENOMEM; goto out; } } if (auth_str) set_str = kasprintf(GFP_KERNEL, "%s,%s", new_setting, auth_str); else set_str = kasprintf(GFP_KERNEL, "%s;", new_setting); if (!set_str) { ret = -ENOMEM; goto out; } ret = tlmi_simple_call(LENOVO_DEBUG_CMD_GUID, set_str); if (ret) goto out; if (!ret && !tlmi_priv.pending_changes) { tlmi_priv.pending_changes = true; /* let userland know it may need to check reboot pending again */ kobject_uevent(&tlmi_priv.class_dev->kobj, KOBJ_CHANGE); } out: kfree(auth_str); kfree(set_str); kfree(new_setting); return ret ?: count; } static struct kobj_attribute debug_cmd = __ATTR_WO(debug_cmd); /* ---- Initialisation --------------------------------------------------------- */ static void tlmi_release_attr(void) { int i; /* Attribute structures */ for (i = 0; i < TLMI_SETTINGS_COUNT; i++) { if (tlmi_priv.setting[i]) { sysfs_remove_group(&tlmi_priv.setting[i]->kobj, &tlmi_attr_group); kobject_put(&tlmi_priv.setting[i]->kobj); } } sysfs_remove_file(&tlmi_priv.attribute_kset->kobj, &pending_reboot.attr); if (tlmi_priv.can_debug_cmd && debug_support) sysfs_remove_file(&tlmi_priv.attribute_kset->kobj, &debug_cmd.attr); kset_unregister(tlmi_priv.attribute_kset); /* Free up any saved signatures */ kfree(tlmi_priv.pwd_admin->signature); kfree(tlmi_priv.pwd_admin->save_signature); /* Authentication structures */ sysfs_remove_group(&tlmi_priv.pwd_admin->kobj, &auth_attr_group); kobject_put(&tlmi_priv.pwd_admin->kobj); sysfs_remove_group(&tlmi_priv.pwd_power->kobj, &auth_attr_group); kobject_put(&tlmi_priv.pwd_power->kobj); if (tlmi_priv.opcode_support) { sysfs_remove_group(&tlmi_priv.pwd_system->kobj, &auth_attr_group); kobject_put(&tlmi_priv.pwd_system->kobj); sysfs_remove_group(&tlmi_priv.pwd_hdd->kobj, &auth_attr_group); kobject_put(&tlmi_priv.pwd_hdd->kobj); sysfs_remove_group(&tlmi_priv.pwd_nvme->kobj, &auth_attr_group); kobject_put(&tlmi_priv.pwd_nvme->kobj); } kset_unregister(tlmi_priv.authentication_kset); } static int tlmi_sysfs_init(void) { int i, ret; ret = fw_attributes_class_get(&fw_attr_class); if (ret) return ret; tlmi_priv.class_dev = device_create(fw_attr_class, NULL, MKDEV(0, 0), NULL, "%s", "thinklmi"); if (IS_ERR(tlmi_priv.class_dev)) { ret = PTR_ERR(tlmi_priv.class_dev); goto fail_class_created; } tlmi_priv.attribute_kset = kset_create_and_add("attributes", NULL, &tlmi_priv.class_dev->kobj); if (!tlmi_priv.attribute_kset) { ret = -ENOMEM; goto fail_device_created; } for (i = 0; i < TLMI_SETTINGS_COUNT; i++) { /* Check if index is a valid setting - skip if it isn't */ if (!tlmi_priv.setting[i]) continue; /* check for duplicate or reserved values */ if (kset_find_obj(tlmi_priv.attribute_kset, tlmi_priv.setting[i]->display_name) || !strcmp(tlmi_priv.setting[i]->display_name, "Reserved")) { pr_debug("duplicate or reserved attribute name found - %s\n", tlmi_priv.setting[i]->display_name); kfree(tlmi_priv.setting[i]->possible_values); kfree(tlmi_priv.setting[i]); tlmi_priv.setting[i] = NULL; continue; } /* Build attribute */ tlmi_priv.setting[i]->kobj.kset = tlmi_priv.attribute_kset; ret = kobject_add(&tlmi_priv.setting[i]->kobj, NULL, "%s", tlmi_priv.setting[i]->display_name); if (ret) goto fail_create_attr; ret = sysfs_create_group(&tlmi_priv.setting[i]->kobj, &tlmi_attr_group); if (ret) goto fail_create_attr; } ret = sysfs_create_file(&tlmi_priv.attribute_kset->kobj, &pending_reboot.attr); if (ret) goto fail_create_attr; if (tlmi_priv.can_debug_cmd && debug_support) { ret = sysfs_create_file(&tlmi_priv.attribute_kset->kobj, &debug_cmd.attr); if (ret) goto fail_create_attr; } /* Create authentication entries */ tlmi_priv.authentication_kset = kset_create_and_add("authentication", NULL, &tlmi_priv.class_dev->kobj); if (!tlmi_priv.authentication_kset) { ret = -ENOMEM; goto fail_create_attr; } tlmi_priv.pwd_admin->kobj.kset = tlmi_priv.authentication_kset; ret = kobject_add(&tlmi_priv.pwd_admin->kobj, NULL, "%s", "Admin"); if (ret) goto fail_create_attr; ret = sysfs_create_group(&tlmi_priv.pwd_admin->kobj, &auth_attr_group); if (ret) goto fail_create_attr; tlmi_priv.pwd_power->kobj.kset = tlmi_priv.authentication_kset; ret = kobject_add(&tlmi_priv.pwd_power->kobj, NULL, "%s", "Power-on"); if (ret) goto fail_create_attr; ret = sysfs_create_group(&tlmi_priv.pwd_power->kobj, &auth_attr_group); if (ret) goto fail_create_attr; if (tlmi_priv.opcode_support) { tlmi_priv.pwd_system->kobj.kset = tlmi_priv.authentication_kset; ret = kobject_add(&tlmi_priv.pwd_system->kobj, NULL, "%s", "System"); if (ret) goto fail_create_attr; ret = sysfs_create_group(&tlmi_priv.pwd_system->kobj, &auth_attr_group); if (ret) goto fail_create_attr; tlmi_priv.pwd_hdd->kobj.kset = tlmi_priv.authentication_kset; ret = kobject_add(&tlmi_priv.pwd_hdd->kobj, NULL, "%s", "HDD"); if (ret) goto fail_create_attr; ret = sysfs_create_group(&tlmi_priv.pwd_hdd->kobj, &auth_attr_group); if (ret) goto fail_create_attr; tlmi_priv.pwd_nvme->kobj.kset = tlmi_priv.authentication_kset; ret = kobject_add(&tlmi_priv.pwd_nvme->kobj, NULL, "%s", "NVMe"); if (ret) goto fail_create_attr; ret = sysfs_create_group(&tlmi_priv.pwd_nvme->kobj, &auth_attr_group); if (ret) goto fail_create_attr; } return ret; fail_create_attr: tlmi_release_attr(); fail_device_created: device_destroy(fw_attr_class, MKDEV(0, 0)); fail_class_created: fw_attributes_class_put(); return ret; } /* ---- Base Driver -------------------------------------------------------- */ static struct tlmi_pwd_setting *tlmi_create_auth(const char *pwd_type, const char *pwd_role) { struct tlmi_pwd_setting *new_pwd; new_pwd = kzalloc(sizeof(struct tlmi_pwd_setting), GFP_KERNEL); if (!new_pwd) return NULL; strscpy(new_pwd->kbdlang, "us", TLMI_LANG_MAXLEN); new_pwd->encoding = TLMI_ENCODING_ASCII; new_pwd->pwd_type = pwd_type; new_pwd->role = pwd_role; new_pwd->minlen = tlmi_priv.pwdcfg.core.min_length; new_pwd->maxlen = tlmi_priv.pwdcfg.core.max_length; new_pwd->index = 0; kobject_init(&new_pwd->kobj, &tlmi_pwd_setting_ktype); return new_pwd; } static int tlmi_analyze(void) { acpi_status status; int i, ret; if (wmi_has_guid(LENOVO_SET_BIOS_SETTINGS_GUID) && wmi_has_guid(LENOVO_SAVE_BIOS_SETTINGS_GUID)) tlmi_priv.can_set_bios_settings = true; if (wmi_has_guid(LENOVO_GET_BIOS_SELECTIONS_GUID)) tlmi_priv.can_get_bios_selections = true; if (wmi_has_guid(LENOVO_SET_BIOS_PASSWORD_GUID)) tlmi_priv.can_set_bios_password = true; if (wmi_has_guid(LENOVO_BIOS_PASSWORD_SETTINGS_GUID)) tlmi_priv.can_get_password_settings = true; if (wmi_has_guid(LENOVO_DEBUG_CMD_GUID)) tlmi_priv.can_debug_cmd = true; if (wmi_has_guid(LENOVO_OPCODE_IF_GUID)) tlmi_priv.opcode_support = true; if (wmi_has_guid(LENOVO_SET_BIOS_CERT_GUID) && wmi_has_guid(LENOVO_SET_BIOS_SETTING_CERT_GUID) && wmi_has_guid(LENOVO_SAVE_BIOS_SETTING_CERT_GUID)) tlmi_priv.certificate_support = true; /* * Try to find the number of valid settings of this machine * and use it to create sysfs attributes. */ for (i = 0; i < TLMI_SETTINGS_COUNT; ++i) { struct tlmi_attr_setting *setting; char *item = NULL; char *p; tlmi_priv.setting[i] = NULL; status = tlmi_setting(i, &item, LENOVO_BIOS_SETTING_GUID); if (ACPI_FAILURE(status)) break; if (!item) break; if (!*item) { kfree(item); continue; } /* It is not allowed to have '/' for file name. Convert it into '\'. */ strreplace(item, '/', '\\'); /* Remove the value part */ p = strchrnul(item, ','); *p = '\0'; /* Create a setting entry */ setting = kzalloc(sizeof(*setting), GFP_KERNEL); if (!setting) { ret = -ENOMEM; kfree(item); goto fail_clear_attr; } setting->index = i; strscpy(setting->display_name, item, TLMI_SETTINGS_MAXLEN); /* If BIOS selections supported, load those */ if (tlmi_priv.can_get_bios_selections) { ret = tlmi_get_bios_selections(setting->display_name, &setting->possible_values); if (ret || !setting->possible_values) pr_info("Error retrieving possible values for %d : %s\n", i, setting->display_name); } else { /* * Older Thinkstations don't support the bios_selections API. * Instead they store this as a [Optional:Option1,Option2] section of the * name string. * Try and pull that out if it's available. */ char *optitem, *optstart, *optend; if (!tlmi_setting(setting->index, &optitem, LENOVO_BIOS_SETTING_GUID)) { optstart = strstr(optitem, "[Optional:"); if (optstart) { optstart += strlen("[Optional:"); optend = strstr(optstart, "]"); if (optend) setting->possible_values = kstrndup(optstart, optend - optstart, GFP_KERNEL); } kfree(optitem); } } /* * firmware-attributes requires that possible_values are separated by ';' but * Lenovo FW uses ','. Replace appropriately. */ if (setting->possible_values) strreplace(setting->possible_values, ',', ';'); kobject_init(&setting->kobj, &tlmi_attr_setting_ktype); tlmi_priv.setting[i] = setting; kfree(item); } /* Create password setting structure */ ret = tlmi_get_pwd_settings(&tlmi_priv.pwdcfg); if (ret) goto fail_clear_attr; /* All failures below boil down to kmalloc failures */ ret = -ENOMEM; tlmi_priv.pwd_admin = tlmi_create_auth("pap", "bios-admin"); if (!tlmi_priv.pwd_admin) goto fail_clear_attr; if (tlmi_priv.pwdcfg.core.password_state & TLMI_PAP_PWD) tlmi_priv.pwd_admin->valid = true; tlmi_priv.pwd_power = tlmi_create_auth("pop", "power-on"); if (!tlmi_priv.pwd_power) goto fail_clear_attr; if (tlmi_priv.pwdcfg.core.password_state & TLMI_POP_PWD) tlmi_priv.pwd_power->valid = true; if (tlmi_priv.opcode_support) { tlmi_priv.pwd_system = tlmi_create_auth("smp", "system"); if (!tlmi_priv.pwd_system) goto fail_clear_attr; if (tlmi_priv.pwdcfg.core.password_state & TLMI_SMP_PWD) tlmi_priv.pwd_system->valid = true; tlmi_priv.pwd_hdd = tlmi_create_auth("hdd", "hdd"); if (!tlmi_priv.pwd_hdd) goto fail_clear_attr; tlmi_priv.pwd_nvme = tlmi_create_auth("nvm", "nvme"); if (!tlmi_priv.pwd_nvme) goto fail_clear_attr; if (tlmi_priv.pwdcfg.core.password_state & TLMI_HDD_PWD) { /* Check if PWD is configured and set index to first drive found */ if (tlmi_priv.pwdcfg.ext.hdd_user_password || tlmi_priv.pwdcfg.ext.hdd_master_password) { tlmi_priv.pwd_hdd->valid = true; if (tlmi_priv.pwdcfg.ext.hdd_master_password) tlmi_priv.pwd_hdd->index = ffs(tlmi_priv.pwdcfg.ext.hdd_master_password) - 1; else tlmi_priv.pwd_hdd->index = ffs(tlmi_priv.pwdcfg.ext.hdd_user_password) - 1; } if (tlmi_priv.pwdcfg.ext.nvme_user_password || tlmi_priv.pwdcfg.ext.nvme_master_password) { tlmi_priv.pwd_nvme->valid = true; if (tlmi_priv.pwdcfg.ext.nvme_master_password) tlmi_priv.pwd_nvme->index = ffs(tlmi_priv.pwdcfg.ext.nvme_master_password) - 1; else tlmi_priv.pwd_nvme->index = ffs(tlmi_priv.pwdcfg.ext.nvme_user_password) - 1; } } } if (tlmi_priv.certificate_support && (tlmi_priv.pwdcfg.core.password_state & TLMI_CERT)) tlmi_priv.pwd_admin->cert_installed = true; return 0; fail_clear_attr: for (i = 0; i < TLMI_SETTINGS_COUNT; ++i) { if (tlmi_priv.setting[i]) { kfree(tlmi_priv.setting[i]->possible_values); kfree(tlmi_priv.setting[i]); } } kfree(tlmi_priv.pwd_admin); kfree(tlmi_priv.pwd_power); kfree(tlmi_priv.pwd_system); kfree(tlmi_priv.pwd_hdd); kfree(tlmi_priv.pwd_nvme); return ret; } static void tlmi_remove(struct wmi_device *wdev) { tlmi_release_attr(); device_destroy(fw_attr_class, MKDEV(0, 0)); fw_attributes_class_put(); } static int tlmi_probe(struct wmi_device *wdev, const void *context) { int ret; ret = tlmi_analyze(); if (ret) return ret; return tlmi_sysfs_init(); } static const struct wmi_device_id tlmi_id_table[] = { { .guid_string = LENOVO_BIOS_SETTING_GUID }, { } }; MODULE_DEVICE_TABLE(wmi, tlmi_id_table); static struct wmi_driver tlmi_driver = { .driver = { .name = "think-lmi", }, .id_table = tlmi_id_table, .probe = tlmi_probe, .remove = tlmi_remove, }; MODULE_AUTHOR("Sugumaran L "); MODULE_AUTHOR("Mark Pearson "); MODULE_AUTHOR("Corentin Chary "); MODULE_DESCRIPTION("ThinkLMI Driver"); MODULE_LICENSE("GPL"); module_wmi_driver(tlmi_driver);