Crate efivar

efivar is a crate for manipulating EFI variables using the OS interface. This crate is mainly used by efiboot to implement its functionality.

On Linux, it is assumed that efivarfs is mounted and available at /sys/firmware/efi/efivars, which should be the default nowadays on all major distros.

On Windows, it uses the Get/SetFirmwareEnvironmentVariable family of functions, which require administrative rights. This also requires adjusting the security token for the current thread to include SeSystemEnvironmentPrivilege. This is done during the initialization of SystemManager (see SystemManager::new() ).

In-memory and filesystem storage are also provided for testing purposes, or as a way to dump system variables to an external file.

Modules

• efi
  EFI constants based on the UEFI specification

Enums

• Error
  Describes an error returned by EFI variable operations

Traits

• VarEnumerator
  Represents the capability of enumerating EFI variables
• VarManager
  Represents an EFI variable manager that can read, write and list variables
• VarManagerEx
  Represents an EFI variable manager that can read (both static and dynamic sized variables), write and list variables
• VarReader
  Represents the capability of reading EFI variables
• VarReaderEx
  Represents the capability of reading EFI variables of a dynamic size
• VarWriter
  Represents the capability of writing EFI variables

Functions

• system
  Returns a VarManager that represents the firmware variables of the running system

Type Definitions

• Result
  Result type for this crate’s API functions