diff options
Diffstat (limited to 'drivers/firmware/efi/efivars.c')
| -rw-r--r-- | drivers/firmware/efi/efivars.c | 671 |
1 files changed, 0 insertions, 671 deletions
diff --git a/drivers/firmware/efi/efivars.c b/drivers/firmware/efi/efivars.c deleted file mode 100644 index ea0bc39dc965..000000000000 --- a/drivers/firmware/efi/efivars.c +++ /dev/null @@ -1,671 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0+ -/* - * Originally from efivars.c, - * - * Copyright (C) 2001,2003,2004 Dell <Matt_Domsch@dell.com> - * Copyright (C) 2004 Intel Corporation <matthew.e.tolentino@intel.com> - * - * This code takes all variables accessible from EFI runtime and - * exports them via sysfs - */ - -#include <linux/efi.h> -#include <linux/module.h> -#include <linux/slab.h> -#include <linux/ucs2_string.h> -#include <linux/compat.h> - -#define EFIVARS_VERSION "0.08" -#define EFIVARS_DATE "2004-May-17" - -MODULE_AUTHOR("Matt Domsch <Matt_Domsch@Dell.com>"); -MODULE_DESCRIPTION("sysfs interface to EFI Variables"); -MODULE_LICENSE("GPL"); -MODULE_VERSION(EFIVARS_VERSION); - -static LIST_HEAD(efivar_sysfs_list); - -static struct kset *efivars_kset; - -static struct bin_attribute *efivars_new_var; -static struct bin_attribute *efivars_del_var; - -struct compat_efi_variable { - efi_char16_t VariableName[EFI_VAR_NAME_LEN/sizeof(efi_char16_t)]; - efi_guid_t VendorGuid; - __u32 DataSize; - __u8 Data[1024]; - __u32 Status; - __u32 Attributes; -} __packed; - -struct efivar_attribute { - struct attribute attr; - ssize_t (*show) (struct efivar_entry *entry, char *buf); - ssize_t (*store)(struct efivar_entry *entry, const char *buf, size_t count); -}; - -#define EFIVAR_ATTR(_name, _mode, _show, _store) \ -struct efivar_attribute efivar_attr_##_name = { \ - .attr = {.name = __stringify(_name), .mode = _mode}, \ - .show = _show, \ - .store = _store, \ -}; - -#define to_efivar_attr(_attr) container_of(_attr, struct efivar_attribute, attr) -#define to_efivar_entry(obj) container_of(obj, struct efivar_entry, kobj) - -/* - * Prototype for sysfs creation function - */ -static int -efivar_create_sysfs_entry(struct efivar_entry *new_var); - -static ssize_t -efivar_guid_read(struct efivar_entry *entry, char *buf) -{ - struct efi_variable *var = &entry->var; - char *str = buf; - - if (!entry || !buf) - return 0; - - efi_guid_to_str(&var->VendorGuid, str); - str += strlen(str); - str += sprintf(str, "\n"); - - return str - buf; -} - -static ssize_t -efivar_attr_read(struct efivar_entry *entry, char *buf) -{ - struct efi_variable *var = &entry->var; - unsigned long size = sizeof(var->Data); - char *str = buf; - int ret; - - if (!entry || !buf) - return -EINVAL; - - ret = efivar_entry_get(entry, &var->Attributes, &size, var->Data); - var->DataSize = size; - if (ret) - return -EIO; - - if (var->Attributes & EFI_VARIABLE_NON_VOLATILE) - str += sprintf(str, "EFI_VARIABLE_NON_VOLATILE\n"); - if (var->Attributes & EFI_VARIABLE_BOOTSERVICE_ACCESS) - str += sprintf(str, "EFI_VARIABLE_BOOTSERVICE_ACCESS\n"); - if (var->Attributes & EFI_VARIABLE_RUNTIME_ACCESS) - str += sprintf(str, "EFI_VARIABLE_RUNTIME_ACCESS\n"); - if (var->Attributes & EFI_VARIABLE_HARDWARE_ERROR_RECORD) - str += sprintf(str, "EFI_VARIABLE_HARDWARE_ERROR_RECORD\n"); - if (var->Attributes & EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS) - str += sprintf(str, - "EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS\n"); - if (var->Attributes & - EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS) - str += sprintf(str, - "EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS\n"); - if (var->Attributes & EFI_VARIABLE_APPEND_WRITE) - str += sprintf(str, "EFI_VARIABLE_APPEND_WRITE\n"); - return str - buf; -} - -static ssize_t -efivar_size_read(struct efivar_entry *entry, char *buf) -{ - struct efi_variable *var = &entry->var; - unsigned long size = sizeof(var->Data); - char *str = buf; - int ret; - - if (!entry || !buf) - return -EINVAL; - - ret = efivar_entry_get(entry, &var->Attributes, &size, var->Data); - var->DataSize = size; - if (ret) - return -EIO; - - str += sprintf(str, "0x%lx\n", var->DataSize); - return str - buf; -} - -static ssize_t -efivar_data_read(struct efivar_entry *entry, char *buf) -{ - struct efi_variable *var = &entry->var; - unsigned long size = sizeof(var->Data); - int ret; - - if (!entry || !buf) - return -EINVAL; - - ret = efivar_entry_get(entry, &var->Attributes, &size, var->Data); - var->DataSize = size; - if (ret) - return -EIO; - - memcpy(buf, var->Data, var->DataSize); - return var->DataSize; -} - -static inline int -sanity_check(struct efi_variable *var, efi_char16_t *name, efi_guid_t vendor, - unsigned long size, u32 attributes, u8 *data) -{ - /* - * If only updating the variable data, then the name - * and guid should remain the same - */ - if (memcmp(name, var->VariableName, sizeof(var->VariableName)) || - efi_guidcmp(vendor, var->VendorGuid)) { - printk(KERN_ERR "efivars: Cannot edit the wrong variable!\n"); - return -EINVAL; - } - - if ((size <= 0) || (attributes == 0)){ - printk(KERN_ERR "efivars: DataSize & Attributes must be valid!\n"); - return -EINVAL; - } - - if ((attributes & ~EFI_VARIABLE_MASK) != 0 || - efivar_validate(vendor, name, data, size) == false) { - printk(KERN_ERR "efivars: Malformed variable content\n"); - return -EINVAL; - } - - return 0; -} - -static void -copy_out_compat(struct efi_variable *dst, struct compat_efi_variable *src) -{ - memcpy(dst->VariableName, src->VariableName, EFI_VAR_NAME_LEN); - memcpy(dst->Data, src->Data, sizeof(src->Data)); - - dst->VendorGuid = src->VendorGuid; - dst->DataSize = src->DataSize; - dst->Attributes = src->Attributes; -} - -/* - * We allow each variable to be edited via rewriting the - * entire efi variable structure. - */ -static ssize_t -efivar_store_raw(struct efivar_entry *entry, const char *buf, size_t count) -{ - struct efi_variable *new_var, *var = &entry->var; - efi_char16_t *name; - unsigned long size; - efi_guid_t vendor; - u32 attributes; - u8 *data; - int err; - - if (!entry || !buf) - return -EINVAL; - - if (in_compat_syscall()) { - struct compat_efi_variable *compat; - - if (count != sizeof(*compat)) - return -EINVAL; - - compat = (struct compat_efi_variable *)buf; - attributes = compat->Attributes; - vendor = compat->VendorGuid; - name = compat->VariableName; - size = compat->DataSize; - data = compat->Data; - - err = sanity_check(var, name, vendor, size, attributes, data); - if (err) - return err; - - copy_out_compat(&entry->var, compat); - } else { - if (count != sizeof(struct efi_variable)) - return -EINVAL; - - new_var = (struct efi_variable *)buf; - - attributes = new_var->Attributes; - vendor = new_var->VendorGuid; - name = new_var->VariableName; - size = new_var->DataSize; - data = new_var->Data; - - err = sanity_check(var, name, vendor, size, attributes, data); - if (err) - return err; - - memcpy(&entry->var, new_var, count); - } - - err = efivar_entry_set(entry, attributes, size, data, NULL); - if (err) { - printk(KERN_WARNING "efivars: set_variable() failed: status=%d\n", err); - return -EIO; - } - - return count; -} - -static ssize_t -efivar_show_raw(struct efivar_entry *entry, char *buf) -{ - struct efi_variable *var = &entry->var; - struct compat_efi_variable *compat; - unsigned long datasize = sizeof(var->Data); - size_t size; - int ret; - - if (!entry || !buf) - return 0; - - ret = efivar_entry_get(entry, &var->Attributes, &datasize, var->Data); - var->DataSize = datasize; - if (ret) - return -EIO; - - if (in_compat_syscall()) { - compat = (struct compat_efi_variable *)buf; - - size = sizeof(*compat); - memcpy(compat->VariableName, var->VariableName, - EFI_VAR_NAME_LEN); - memcpy(compat->Data, var->Data, sizeof(compat->Data)); - - compat->VendorGuid = var->VendorGuid; - compat->DataSize = var->DataSize; - compat->Attributes = var->Attributes; - } else { - size = sizeof(*var); - memcpy(buf, var, size); - } - - return size; -} - -/* - * Generic read/write functions that call the specific functions of - * the attributes... - */ -static ssize_t efivar_attr_show(struct kobject *kobj, struct attribute *attr, - char *buf) -{ - struct efivar_entry *var = to_efivar_entry(kobj); - struct efivar_attribute *efivar_attr = to_efivar_attr(attr); - ssize_t ret = -EIO; - - if (!capable(CAP_SYS_ADMIN)) - return -EACCES; - - if (efivar_attr->show) { - ret = efivar_attr->show(var, buf); - } - return ret; -} - -static ssize_t efivar_attr_store(struct kobject *kobj, struct attribute *attr, - const char *buf, size_t count) -{ - struct efivar_entry *var = to_efivar_entry(kobj); - struct efivar_attribute *efivar_attr = to_efivar_attr(attr); - ssize_t ret = -EIO; - - if (!capable(CAP_SYS_ADMIN)) - return -EACCES; - - if (efivar_attr->store) - ret = efivar_attr->store(var, buf, count); - - return ret; -} - -static const struct sysfs_ops efivar_attr_ops = { - .show = efivar_attr_show, - .store = efivar_attr_store, -}; - -static void efivar_release(struct kobject *kobj) -{ - struct efivar_entry *var = to_efivar_entry(kobj); - kfree(var); -} - -static EFIVAR_ATTR(guid, 0400, efivar_guid_read, NULL); -static EFIVAR_ATTR(attributes, 0400, efivar_attr_read, NULL); -static EFIVAR_ATTR(size, 0400, efivar_size_read, NULL); -static EFIVAR_ATTR(data, 0400, efivar_data_read, NULL); -static EFIVAR_ATTR(raw_var, 0600, efivar_show_raw, efivar_store_raw); - -static struct attribute *def_attrs[] = { - &efivar_attr_guid.attr, - &efivar_attr_size.attr, - &efivar_attr_attributes.attr, - &efivar_attr_data.attr, - &efivar_attr_raw_var.attr, - NULL, -}; -ATTRIBUTE_GROUPS(def); - -static struct kobj_type efivar_ktype = { - .release = efivar_release, - .sysfs_ops = &efivar_attr_ops, - .default_groups = def_groups, -}; - -static ssize_t efivar_create(struct file *filp, struct kobject *kobj, - struct bin_attribute *bin_attr, - char *buf, loff_t pos, size_t count) -{ - struct compat_efi_variable *compat = (struct compat_efi_variable *)buf; - struct efi_variable *new_var = (struct efi_variable *)buf; - struct efivar_entry *new_entry; - bool need_compat = in_compat_syscall(); - efi_char16_t *name; - unsigned long size; - u32 attributes; - u8 *data; - int err; - - if (!capable(CAP_SYS_ADMIN)) - return -EACCES; - - if (need_compat) { - if (count != sizeof(*compat)) - return -EINVAL; - - attributes = compat->Attributes; - name = compat->VariableName; - size = compat->DataSize; - data = compat->Data; - } else { - if (count != sizeof(*new_var)) - return -EINVAL; - - attributes = new_var->Attributes; - name = new_var->VariableName; - size = new_var->DataSize; - data = new_var->Data; - } - - if ((attributes & ~EFI_VARIABLE_MASK) != 0 || - efivar_validate(new_var->VendorGuid, name, data, - size) == false) { - printk(KERN_ERR "efivars: Malformed variable content\n"); - return -EINVAL; - } - - new_entry = kzalloc(sizeof(*new_entry), GFP_KERNEL); - if (!new_entry) - return -ENOMEM; - - if (need_compat) - copy_out_compat(&new_entry->var, compat); - else - memcpy(&new_entry->var, new_var, sizeof(*new_var)); - - err = efivar_entry_set(new_entry, attributes, size, - data, &efivar_sysfs_list); - if (err) { - if (err == -EEXIST) - err = -EINVAL; - goto out; - } - - if (efivar_create_sysfs_entry(new_entry)) { - printk(KERN_WARNING "efivars: failed to create sysfs entry.\n"); - kfree(new_entry); - } - return count; - -out: - kfree(new_entry); - return err; -} - -static ssize_t efivar_delete(struct file *filp, struct kobject *kobj, - struct bin_attribute *bin_attr, - char *buf, loff_t pos, size_t count) -{ - struct efi_variable *del_var = (struct efi_variable *)buf; - struct compat_efi_variable *compat; - struct efivar_entry *entry; - efi_char16_t *name; - efi_guid_t vendor; - int err = 0; - - if (!capable(CAP_SYS_ADMIN)) - return -EACCES; - - if (in_compat_syscall()) { - if (count != sizeof(*compat)) - return -EINVAL; - - compat = (struct compat_efi_variable *)buf; - name = compat->VariableName; - vendor = compat->VendorGuid; - } else { - if (count != sizeof(*del_var)) - return -EINVAL; - - name = del_var->VariableName; - vendor = del_var->VendorGuid; - } - - if (efivar_entry_iter_begin()) - return -EINTR; - entry = efivar_entry_find(name, vendor, &efivar_sysfs_list, true); - if (!entry) - err = -EINVAL; - else if (__efivar_entry_delete(entry)) - err = -EIO; - - if (err) { - efivar_entry_iter_end(); - return err; - } - - if (!entry->scanning) { - efivar_entry_iter_end(); - efivar_unregister(entry); - } else - efivar_entry_iter_end(); - - /* It's dead Jim.... */ - return count; -} - -/** - * efivar_create_sysfs_entry - create a new entry in sysfs - * @new_var: efivar entry to create - * - * Returns 0 on success, negative error code on failure - */ -static int -efivar_create_sysfs_entry(struct efivar_entry *new_var) -{ - int short_name_size; - char *short_name; - unsigned long utf8_name_size; - efi_char16_t *variable_name = new_var->var.VariableName; - int ret; - - /* - * Length of the variable bytes in UTF8, plus the '-' separator, - * plus the GUID, plus trailing NUL - */ - utf8_name_size = ucs2_utf8size(variable_name); - short_name_size = utf8_name_size + 1 + EFI_VARIABLE_GUID_LEN + 1; - - short_name = kmalloc(short_name_size, GFP_KERNEL); - if (!short_name) - return -ENOMEM; - - ucs2_as_utf8(short_name, variable_name, short_name_size); - - /* This is ugly, but necessary to separate one vendor's - private variables from another's. */ - short_name[utf8_name_size] = '-'; - efi_guid_to_str(&new_var->var.VendorGuid, - short_name + utf8_name_size + 1); - - new_var->kobj.kset = efivars_kset; - - ret = kobject_init_and_add(&new_var->kobj, &efivar_ktype, - NULL, "%s", short_name); - kfree(short_name); - if (ret) { - kobject_put(&new_var->kobj); - return ret; - } - - kobject_uevent(&new_var->kobj, KOBJ_ADD); - if (efivar_entry_add(new_var, &efivar_sysfs_list)) { - efivar_unregister(new_var); - return -EINTR; - } - - return 0; -} - -static int -create_efivars_bin_attributes(void) -{ - struct bin_attribute *attr; - int error; - - /* new_var */ - attr = kzalloc(sizeof(*attr), GFP_KERNEL); - if (!attr) - return -ENOMEM; - - attr->attr.name = "new_var"; - attr->attr.mode = 0200; - attr->write = efivar_create; - efivars_new_var = attr; - - /* del_var */ - attr = kzalloc(sizeof(*attr), GFP_KERNEL); - if (!attr) { - error = -ENOMEM; - goto out_free; - } - attr->attr.name = "del_var"; - attr->attr.mode = 0200; - attr->write = efivar_delete; - efivars_del_var = attr; - - sysfs_bin_attr_init(efivars_new_var); - sysfs_bin_attr_init(efivars_del_var); - - /* Register */ - error = sysfs_create_bin_file(&efivars_kset->kobj, efivars_new_var); - if (error) { - printk(KERN_ERR "efivars: unable to create new_var sysfs file" - " due to error %d\n", error); - goto out_free; - } - - error = sysfs_create_bin_file(&efivars_kset->kobj, efivars_del_var); - if (error) { - printk(KERN_ERR "efivars: unable to create del_var sysfs file" - " due to error %d\n", error); - sysfs_remove_bin_file(&efivars_kset->kobj, efivars_new_var); - goto out_free; - } - - return 0; -out_free: - kfree(efivars_del_var); - efivars_del_var = NULL; - kfree(efivars_new_var); - efivars_new_var = NULL; - return error; -} - -static int efivars_sysfs_callback(efi_char16_t *name, efi_guid_t vendor, - unsigned long name_size, void *data) -{ - struct efivar_entry *entry; - - entry = kzalloc(sizeof(*entry), GFP_KERNEL); - if (!entry) - return -ENOMEM; - - memcpy(entry->var.VariableName, name, name_size); - memcpy(&(entry->var.VendorGuid), &vendor, sizeof(efi_guid_t)); - - efivar_create_sysfs_entry(entry); - - return 0; -} - -static int efivar_sysfs_destroy(struct efivar_entry *entry, void *data) -{ - int err = efivar_entry_remove(entry); - - if (err) - return err; - efivar_unregister(entry); - return 0; -} - -static void efivars_sysfs_exit(void) -{ - /* Remove all entries and destroy */ - int err; - - err = __efivar_entry_iter(efivar_sysfs_destroy, &efivar_sysfs_list, - NULL, NULL); - if (err) { - pr_err("efivars: Failed to destroy sysfs entries\n"); - return; - } - - if (efivars_new_var) - sysfs_remove_bin_file(&efivars_kset->kobj, efivars_new_var); - if (efivars_del_var) - sysfs_remove_bin_file(&efivars_kset->kobj, efivars_del_var); - kfree(efivars_new_var); - kfree(efivars_del_var); - kset_unregister(efivars_kset); -} - -static int efivars_sysfs_init(void) -{ - struct kobject *parent_kobj = efivars_kobject(); - int error = 0; - - /* No efivars has been registered yet */ - if (!parent_kobj || !efivar_supports_writes()) - return 0; - - printk(KERN_INFO "EFI Variables Facility v%s %s\n", EFIVARS_VERSION, - EFIVARS_DATE); - - efivars_kset = kset_create_and_add("vars", NULL, parent_kobj); - if (!efivars_kset) { - printk(KERN_ERR "efivars: Subsystem registration failed.\n"); - return -ENOMEM; - } - - efivar_init(efivars_sysfs_callback, NULL, true, &efivar_sysfs_list); - - error = create_efivars_bin_attributes(); - if (error) { - efivars_sysfs_exit(); - return error; - } - - return 0; -} - -module_init(efivars_sysfs_init); -module_exit(efivars_sysfs_exit); 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