//! UEFI Base Environment //! //! This module defines the base environment for UEFI development. It provides types and macros as //! declared in the UEFI specification, as well as de-facto standard additions provided by the //! reference implementation by Intel. //! //! # Target Configuration //! //! Wherever possible, native rust types are used to represent their UEFI counter-parts. However, //! this means the ABI depends on the implementation of said rust types. Hence, native rust types //! are only used where rust supports a stable ABI of said types, and their ABI matches the ABI //! defined by the UEFI specification. //! //! Nevertheless, even if the ABI of a specific type is marked stable, this does not imply that it //! is the same across architectures. For instance, rust's `u64` type has the same binary //! representation as the `UINT64` type in UEFI. But this does not imply that it has the same //! binary representation on `x86_64` and on `ppc64be`. As a result of this, the compilation of //! this module is tied to the target-configuration you passed to the rust compiler. Wherever //! possible and reasonable, any architecture differences are abstracted, though. This means that //! in most cases you can use this module even though your target-configuration might not match //! the native UEFI target-configuration. //! //! The recommend way to compile your code, is to use the native target-configuration for UEFI. //! These configurations are not necessarily included in the upstream rust compiler. Hence, you //! might have to craft one yourself. For all systems that we can test on, we make sure to push //! the target configuration into upstream rust-lang. //! //! However, there are situations where you want to access UEFI data from a non-native host. For //! instance, a UEFI boot loader might store data in boot variables, formatted according to types //! declared in the UEFI specification. An OS booted thereafter might want to access these //! variables, but it might be compiled with a different target-configuration than the UEFI //! environment that it was booted from. A similar situation occurs when you call UEFI runtime //! functions from your OS. In all those cases, you should very likely be able to use this module //! to interact with UEFI as well. This is, because most bits of the target-configuration of UEFI //! and your OS very likely match. In fact, to figure out whether this is safe, you need to make //! sure that the rust ABI would match in both target-configurations. If it is, all other details //! are handled within this module just fine. //! //! In case of doubt, contact us! //! //! # Core Primitives //! //! Several of the UEFI primitives are represented by native Rust. These have no type aliases or //! other definitions here, but you are recommended to use native rust directly. These include: //! //! * `NULL`, `void *`: Void pointers have a native rust implementation in //! [`c_void`](core::ffi::c_void). `NULL` is represented through //! [`null`](core::ptr::null) and [`is_null()`](core::ptr) for //! all pointer types. //! * `uint8_t`..`uint64_t`, //! `int8_t`..`int64_t`: Fixed-size integers are represented by their native rust equivalents //! (`u8`..`u64`, `i8`..`i64`). //! //! * `UINTN`, `INTN`: Native-sized (or instruction-width sized) integers are represented by //! their native rust equivalents (`usize`, `isize`). //! //! # UEFI Details //! //! The UEFI Specification describes its target environments in detail. Each supported //! architecture has a separate section with details on calling conventions, CPU setup, and more. //! You are highly recommended to conduct the UEFI Specification for details on the programming //! environment. Following a summary of key parts relevant to rust developers: //! //! * Similar to rust, integers are either fixed-size, or native size. This maps nicely to the //! native rust types. The common `long`, `int`, `short` types known from ISO-C are not used. //! Whenever you refer to memory (either pointing to it, or remember the size of a memory //! block), the native size integers should be your tool of choice. //! //! * Even though the CPU might run in any endianness, all stored data is little-endian. That //! means, if you encounter integers split into byte-arrays (e.g., //! `CEfiDevicePathProtocol.length`), you must assume it is little-endian encoded. But if you //! encounter native integers, you must assume they are encoded in native endianness. //! For now the UEFI specification only defines little-endian architectures, hence this did not //! pop up as actual issue. Future extensions might change this, though. //! //! * The Microsoft calling-convention is used. That is, all external calls to UEFI functions //! follow a calling convention that is very similar to that used on Microsoft Windows. All //! such ABI functions must be marked with the right calling-convention. The UEFI Specification //! defines some additional common rules for all its APIs, though. You will most likely not see //! any of these mentioned in the individual API documentions. So here is a short reminder: //! //! * Pointers must reference physical-memory locations (no I/O mappings, no //! virtual addresses, etc.). Once ExitBootServices() was called, and the //! virtual address mapping was set, you must provide virtual-memory //! locations instead. //! * Pointers must be correctly aligned. //! * NULL is disallowed, unless explicitly mentioned otherwise. //! * Data referenced by pointers is undefined on error-return from a //! function. //! * You must not pass data larger than native-size (sizeof(CEfiUSize)) on //! the stack. You must pass them by reference. //! //! * Stack size is at least 128KiB and 16-byte aligned. All stack space might be marked //! non-executable! Once ExitBootServices() was called, you must guarantee at least 4KiB of //! stack space, 16-byte aligned for all runtime services you call. //! Details might differ depending on architectures. But the numbers here should serve as //! ball-park figures. // Target Architecture // // The UEFI Specification explicitly lists all supported target architectures. While external // implementors are free to port UEFI to other targets, we need information on the target // architecture to successfully compile for it. This includes calling-conventions, register // layouts, endianness, and more. Most of these details are hidden in the rust-target-declaration. // However, some details are still left to the actual rust code. // // This initial check just makes sure the compilation is halted with a suitable error message if // the target architecture is not supported. // // We try to minimize conditional compilations as much as possible. A simple search for // `target_arch` should reveal all uses throughout the code-base. If you add your target to this // error-check, you must adjust all other uses as well. // // Similarly, UEFI only defines configurations for little-endian architectures so far. Several // bits of the specification are thus unclear how they would be applied on big-endian systems. We // therefore mark it as unsupported. If you override this, you are on your own. #[cfg(not(any( target_arch = "arm", target_arch = "aarch64", target_arch = "riscv64", target_arch = "x86", target_arch = "x86_64" )))] compile_error!("The target architecture is not supported."); #[cfg(not(target_endian = "little"))] compile_error!("The target endianness is not supported."); // eficall_abi!() // // This macro is the architecture-dependent implementation of eficall!(). See the documentation of // the eficall!() macro for a description. Nowadays, this simply maps to `extern "efiapi"`, since // this has been stabilized with rust-1.68. #[macro_export] #[doc(hidden)] macro_rules! eficall_abi { (($($prefix:tt)*),($($suffix:tt)*)) => { $($prefix)* extern "efiapi" $($suffix)* }; } /// Annotate function with UEFI calling convention /// /// Since rust-1.68 you can use `extern "efiapi"` as calling-convention to achieve the same /// behavior as this macro. This macro is kept for backwards-compatibility only, but will nowadays /// map to `extern "efiapi"`. /// /// This macro takes a function-declaration as argument and produces the same function-declaration /// but annotated with the correct calling convention. Since the default `extern "C"` annotation /// depends on your compiler defaults, we cannot use it. Instead, this macro selects the default /// for your target platform. /// /// Ideally, the macro would expand to `extern ""` so you would be able to write: /// /// ```ignore /// // THIS DOES NOT WORK! /// pub fn eficall!{} foobar() { /// // ... /// } /// ``` /// /// However, macros are evaluated too late for this to work. Instead, the entire construct must be /// wrapped in a macro, which then expands to the same construct but with `extern ""` /// inserted at the correct place: /// /// ``` /// use r_efi::{eficall, eficall_abi}; /// /// eficall!{pub fn foobar() { /// // ... /// }} /// /// type FooBar = eficall!{fn(u8) -> (u8)}; /// ``` /// /// The `eficall!{}` macro takes either a function-type or function-definition as argument. It /// inserts `extern ""` after the function qualifiers, but before the `fn` keyword. /// /// # Internals /// /// The `eficall!{}` macro tries to parse the function header so it can insert `extern ""` at /// the right place. If, for whatever reason, this does not work with a particular syntax, you can /// use the internal `eficall_abi!{}` macro. This macro takes two token-streams as input and /// evaluates to the concatenation of both token-streams, but separated by the selected ABI. /// /// For instance, the following 3 type definitions are equivalent, assuming the selected ABI /// is "C": /// /// ``` /// use r_efi::{eficall, eficall_abi}; /// /// type FooBar1 = unsafe extern "C" fn(u8) -> (u8); /// type FooBar2 = eficall!{unsafe fn(u8) -> (u8)}; /// type FooBar3 = eficall_abi!{(unsafe), (fn(u8) -> (u8))}; /// ``` /// /// # Calling Conventions /// /// The UEFI specification defines the calling convention for each platform individually. It /// usually refers to other standards for details, but adds some restrictions on top. As of this /// writing, it mentions: /// /// * aarch32 / arm: The `aapcs` calling-convention is used. It is native to aarch32 and described /// in a document called /// "Procedure Call Standard for the ARM Architecture". It is openly distributed /// by ARM and widely known under the keyword `aapcs`. /// * aarch64: The `aapcs64` calling-convention is used. It is native to aarch64 and described in /// a document called /// "Procedure Call Standard for the ARM 64-bit Architecture (AArch64)". It is openly /// distributed by ARM and widely known under the keyword `aapcs64`. /// * ia-64: The "P64 C Calling Convention" as described in the /// "Itanium Software Conventions and Runtime Architecture Guide". It is also /// standardized in the "Intel Itanium SAL Specification". /// * RISC-V: The "Standard RISC-V C Calling Convention" is used. The UEFI specification /// describes it in detail, but also refers to the official RISC-V resources for /// detailed information. /// * x86 / ia-32: The `cdecl` C calling convention is used. Originated in the C Language and /// originally tightly coupled to C specifics. Unclear whether a formal /// specification exists (does anyone know?). Most compilers support it under the /// `cdecl` keyword, and in nearly all situations it is the default on x86. /// * x86_64 / amd64 / x64: The `win64` calling-convention is used. It is similar to the `sysv64` /// convention that is used on most non-windows x86_64 systems, but not /// exactly the same. Microsoft provides open documentation on it. See /// MSDN "x64 Software Conventions -> Calling Conventions". /// The UEFI Specification does not directly refer to `win64`, but /// contains a full specification of the calling convention itself. /// /// Note that in most cases the UEFI Specification adds several more restrictions on top of the /// common calling-conventions. These restrictions usually do not affect how the compiler will lay /// out the function calls. Instead, it usually only restricts the set of APIs that are allowed in /// UEFI. Therefore, most compilers already support the calling conventions used on UEFI. /// /// # Variadics /// /// For some reason, the rust compiler allows variadics only in combination with the `"C"` calling /// convention, even if the selected calling-convention matches what `"C"` would select on the /// target platform. Hence, you will very likely be unable to use variadics with this macro. /// Luckily, all of the UEFI functions that use variadics are wrappers around more low-level /// accessors, so they are not necessarily required. #[macro_export] macro_rules! eficall { // Muncher // // The `@munch()` rules are internal and should not be invoked directly. We walk through the // input, moving one token after the other from the suffix into the prefix until we find the // position where to insert `extern ""`. This muncher never drops any tokens, hence we // can safely match invalid statements just fine, as the compiler will later print proper // diagnostics when parsing the macro output. // Once done, we invoke the `eficall_abi!{}` macro, which simply inserts the correct ABI. (@munch(($($prefix:tt)*),(pub $($suffix:tt)*))) => { eficall!{@munch(($($prefix)* pub),($($suffix)*))} }; (@munch(($($prefix:tt)*),(unsafe $($suffix:tt)*))) => { eficall!{@munch(($($prefix)* unsafe),($($suffix)*))} }; (@munch(($($prefix:tt)*),($($suffix:tt)*))) => { eficall_abi!{($($prefix)*),($($suffix)*)} }; // Entry Point // // This captures the entire argument and invokes its own TT-muncher, but splits the input into // prefix and suffix, so the TT-muncher can walk through it. Note that initially everything is // in the suffix and the prefix is empty. ($($arg:tt)*) => { eficall!{@munch((),($($arg)*))} }; } /// Boolean Type /// /// This boolean type works very similar to the rust primitive type of [`bool`]. However, the rust /// primitive type has no stable ABI, hence we provide this type to represent booleans on the FFI /// interface. /// /// UEFI defines booleans to be 1-byte integers, which can only have the values of `0` or `1`. /// However, in practice anything non-zero is considered `true` by nearly all UEFI systems. Hence, /// this type implements a boolean over `u8` and maps `0` to `false`, everything else to `true`. /// /// The binary representation of this type is ABI. That is, you are allowed to transmute from and /// to `u8`. Furthermore, this type never modifies its binary representation. If it was /// initialized as, or transmuted from, a specific integer value, this value will be retained. /// However, on the rust side you will never see the integer value. It instead behaves truly as a /// boolean. If you need access to the integer value, you have to transmute it back to `u8`. #[repr(C)] #[derive(Clone, Copy, Debug, Eq)] pub struct Boolean(u8); /// Single-byte Character Type /// /// The `Char8` type represents single-byte characters. UEFI defines them to be ASCII compatible, /// using the ISO-Latin-1 character set. pub type Char8 = u8; /// Dual-byte Character Type /// /// The `Char16` type represents dual-byte characters. UEFI defines them to be UCS-2 encoded. pub type Char16 = u16; /// Status Codes /// /// UEFI uses the `Status` type to represent all kinds of status codes. This includes return codes /// from functions, but also complex state of different devices and drivers. It is a simple /// `usize`, but wrapped in a rust-type to allow us to implement helpers on this type. Depending /// on the context, different state is stored in it. Note that it is always binary compatible to a /// usize! #[repr(C)] #[derive(Clone, Copy, Debug, Eq, PartialEq)] pub struct Status(usize); /// Object Handles /// /// Handles represent access to an opaque object. Handles are untyped by default, but get a /// meaning when you combine them with an interface. Internally, they are simple void pointers. It /// is the UEFI driver model that applies meaning to them. pub type Handle = *mut core::ffi::c_void; /// Event Objects /// /// Event objects represent hooks into the main-loop of a UEFI environment. They allow to register /// callbacks, to be invoked when a specific event happens. In most cases you use events to /// register timer-based callbacks, as well as chaining events together. Internally, they are /// simple void pointers. It is the UEFI task management that applies meaning to them. pub type Event = *mut core::ffi::c_void; /// Logical Block Addresses /// /// The LBA type is used to denote logical block addresses of block devices. It is a simple 64-bit /// integer, that is used to denote addresses when working with block devices. pub type Lba = u64; /// Thread Priority Levels /// /// The process model of UEFI systems is highly simplified. Priority levels are used to order /// execution of pending tasks. The TPL type denotes a priority level of a specific task. The /// higher the number, the higher the priority. It is a simple integer type, but its range is /// usually highly restricted. The UEFI task management provides constants and accessors for TPLs. pub type Tpl = usize; /// Physical Memory Address /// /// A simple 64bit integer containing a physical memory address. pub type PhysicalAddress = u64; /// Virtual Memory Address /// /// A simple 64bit integer containing a virtual memory address. pub type VirtualAddress = u64; /// Application Entry Point /// /// This type defines the entry-point of UEFI applications. It is ABI and cannot be changed. /// Whenever you load UEFI images, the entry-point is called with this signature. /// /// In most cases the UEFI image (or application) is unloaded when control returns from the entry /// point. In case of UEFI drivers, they can request to stay loaded until an explicit unload. /// /// The system table is provided as mutable pointer. This is, because there is no guarantee that /// timer interrupts do not modify the table. Furthermore, exiting boot services causes several /// modifications on that table. And lastly, the system table lives longer than the function /// invocation, if invoked as an UEFI driver. /// In most cases it is perfectly fine to cast the pointer to a real rust reference. However, this /// should be an explicit decision by the caller. pub type ImageEntryPoint = eficall! {fn(Handle, *mut crate::system::SystemTable) -> Status}; /// Globally Unique Identifiers /// /// The `Guid` type represents globally unique identifiers as defined by RFC-4122 (i.e., only the /// `10x` variant is used), with the caveat that LE is used instead of BE. The type must be 64-bit /// aligned. /// /// Note that only the binary representation of Guids is stable. You are highly recommended to /// interpret Guids as 128bit integers. /// /// UEFI uses the Microsoft-style Guid format. Hence, a lot of documentation and code refers to /// these Guids. If you thusly cannot treat Guids as 128-bit integers, this Guid type allows you /// to access the individual fields of the Microsoft-style Guid. A reminder of the Guid encoding: /// /// ```text /// 0 1 2 3 /// 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 /// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ /// | time_low | /// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ /// | time_mid | time_hi_and_version | /// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ /// |clk_seq_hi_res | clk_seq_low | node (0-1) | /// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ /// | node (2-5) | /// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ /// ``` /// /// The individual fields are encoded as little-endian. Accessors are provided for the Guid /// structure allowing access to these fields in native endian byte order. #[repr(C, align(8))] #[derive(Clone, Copy, Debug, Eq, PartialEq)] pub struct Guid { time_low: [u8; 4], time_mid: [u8; 2], time_hi_and_version: [u8; 2], clk_seq_hi_res: u8, clk_seq_low: u8, node: [u8; 6], } /// Network MAC Address /// /// This type encapsulates a single networking media access control address /// (MAC). It is a simple 32 bytes buffer with no special alignment. Note that /// no comparison function are defined by default, since trailing bytes of the /// address might be random. /// /// The interpretation of the content differs depending on the protocol it is /// used with. See each documentation for details. In most cases this contains /// an Ethernet address. #[repr(C)] #[derive(Clone, Copy, Debug)] pub struct MacAddress { pub addr: [u8; 32], } /// IPv4 Address /// /// Binary representation of an IPv4 address. It is encoded in network byte /// order (i.e., big endian). Note that no special alignment restrictions are /// defined by the standard specification. #[repr(C)] #[derive(Clone, Copy, Debug, Eq, PartialEq, Default)] pub struct Ipv4Address { pub addr: [u8; 4], } /// IPv6 Address /// /// Binary representation of an IPv6 address, encoded in network byte order /// (i.e., big endian). Similar to the IPv4 address, no special alignment /// restrictions are defined by the standard specification. #[repr(C)] #[derive(Clone, Copy, Debug, Eq, PartialEq)] pub struct Ipv6Address { pub addr: [u8; 16], } /// IP Address /// /// A union type over the different IP addresses available. Alignment is always /// fixed to 4-bytes. Note that trailing bytes might be random, so no /// comparison functions are derived. #[repr(C, align(4))] #[derive(Clone, Copy)] pub union IpAddress { pub addr: [u32; 4], pub v4: Ipv4Address, pub v6: Ipv6Address, } impl Boolean { /// Literal False /// /// This constant represents the `false` value of the `Boolean` type. pub const FALSE: Boolean = Boolean(0u8); /// Literal True /// /// This constant represents the `true` value of the `Boolean` type. pub const TRUE: Boolean = Boolean(1u8); } impl From for Boolean { fn from(v: u8) -> Self { Boolean(v) } } impl From for Boolean { fn from(v: bool) -> Self { match v { false => Boolean::FALSE, true => Boolean::TRUE, } } } impl Default for Boolean { fn default() -> Self { Self::FALSE } } impl From for bool { fn from(v: Boolean) -> Self { match v.0 { 0 => false, _ => true, } } } impl PartialEq for Boolean { fn eq(&self, other: &Boolean) -> bool { >::from(*self) == (*other).into() } } impl PartialEq for Boolean { fn eq(&self, other: &bool) -> bool { *other == (*self).into() } } impl Status { const WIDTH: usize = 8usize * core::mem::size_of::(); const MASK: usize = 0xc0 << (Status::WIDTH - 8); const ERROR_MASK: usize = 0x80 << (Status::WIDTH - 8); const WARNING_MASK: usize = 0x00 << (Status::WIDTH - 8); /// Success Code /// /// This code represents a successfull function invocation. Its value is guaranteed to be 0. /// However, note that warnings are considered success as well, so this is not the only code /// that can be returned by UEFI functions on success. However, in nearly all situations /// warnings are not allowed, so the effective result will be SUCCESS. pub const SUCCESS: Status = Status::from_usize(0); // List of predefined error codes pub const LOAD_ERROR: Status = Status::from_usize(1 | Status::ERROR_MASK); pub const INVALID_PARAMETER: Status = Status::from_usize(2 | Status::ERROR_MASK); pub const UNSUPPORTED: Status = Status::from_usize(3 | Status::ERROR_MASK); pub const BAD_BUFFER_SIZE: Status = Status::from_usize(4 | Status::ERROR_MASK); pub const BUFFER_TOO_SMALL: Status = Status::from_usize(5 | Status::ERROR_MASK); pub const NOT_READY: Status = Status::from_usize(6 | Status::ERROR_MASK); pub const DEVICE_ERROR: Status = Status::from_usize(7 | Status::ERROR_MASK); pub const WRITE_PROTECTED: Status = Status::from_usize(8 | Status::ERROR_MASK); pub const OUT_OF_RESOURCES: Status = Status::from_usize(9 | Status::ERROR_MASK); pub const VOLUME_CORRUPTED: Status = Status::from_usize(10 | Status::ERROR_MASK); pub const VOLUME_FULL: Status = Status::from_usize(11 | Status::ERROR_MASK); pub const NO_MEDIA: Status = Status::from_usize(12 | Status::ERROR_MASK); pub const MEDIA_CHANGED: Status = Status::from_usize(13 | Status::ERROR_MASK); pub const NOT_FOUND: Status = Status::from_usize(14 | Status::ERROR_MASK); pub const ACCESS_DENIED: Status = Status::from_usize(15 | Status::ERROR_MASK); pub const NO_RESPONSE: Status = Status::from_usize(16 | Status::ERROR_MASK); pub const NO_MAPPING: Status = Status::from_usize(17 | Status::ERROR_MASK); pub const TIMEOUT: Status = Status::from_usize(18 | Status::ERROR_MASK); pub const NOT_STARTED: Status = Status::from_usize(19 | Status::ERROR_MASK); pub const ALREADY_STARTED: Status = Status::from_usize(20 | Status::ERROR_MASK); pub const ABORTED: Status = Status::from_usize(21 | Status::ERROR_MASK); pub const ICMP_ERROR: Status = Status::from_usize(22 | Status::ERROR_MASK); pub const TFTP_ERROR: Status = Status::from_usize(23 | Status::ERROR_MASK); pub const PROTOCOL_ERROR: Status = Status::from_usize(24 | Status::ERROR_MASK); pub const INCOMPATIBLE_VERSION: Status = Status::from_usize(25 | Status::ERROR_MASK); pub const SECURITY_VIOLATION: Status = Status::from_usize(26 | Status::ERROR_MASK); pub const CRC_ERROR: Status = Status::from_usize(27 | Status::ERROR_MASK); pub const END_OF_MEDIA: Status = Status::from_usize(28 | Status::ERROR_MASK); pub const END_OF_FILE: Status = Status::from_usize(31 | Status::ERROR_MASK); pub const INVALID_LANGUAGE: Status = Status::from_usize(32 | Status::ERROR_MASK); pub const COMPROMISED_DATA: Status = Status::from_usize(33 | Status::ERROR_MASK); pub const IP_ADDRESS_CONFLICT: Status = Status::from_usize(34 | Status::ERROR_MASK); pub const HTTP_ERROR: Status = Status::from_usize(35 | Status::ERROR_MASK); // List of error codes from protocols // UDP4 pub const NETWORK_UNREACHABLE: Status = Status::from_usize(100 | Status::ERROR_MASK); pub const HOST_UNREACHABLE: Status = Status::from_usize(101 | Status::ERROR_MASK); pub const PROTOCOL_UNREACHABLE: Status = Status::from_usize(102 | Status::ERROR_MASK); pub const PORT_UNREACHABLE: Status = Status::from_usize(103 | Status::ERROR_MASK); // TCP4 pub const CONNECTION_FIN: Status = Status::from_usize(104 | Status::ERROR_MASK); pub const CONNECTION_RESET: Status = Status::from_usize(105 | Status::ERROR_MASK); pub const CONNECTION_REFUSED: Status = Status::from_usize(106 | Status::ERROR_MASK); // List of predefined warning codes pub const WARN_UNKNOWN_GLYPH: Status = Status::from_usize(1 | Status::WARNING_MASK); pub const WARN_DELETE_FAILURE: Status = Status::from_usize(2 | Status::WARNING_MASK); pub const WARN_WRITE_FAILURE: Status = Status::from_usize(3 | Status::WARNING_MASK); pub const WARN_BUFFER_TOO_SMALL: Status = Status::from_usize(4 | Status::WARNING_MASK); pub const WARN_STALE_DATA: Status = Status::from_usize(5 | Status::WARNING_MASK); pub const WARN_FILE_SYSTEM: Status = Status::from_usize(6 | Status::WARNING_MASK); pub const WARN_RESET_REQUIRED: Status = Status::from_usize(7 | Status::WARNING_MASK); /// Create Status Code from Integer /// /// This takes the literal value of a status code and turns it into a `Status` object. Note /// that we want it as `const fn` so we cannot use `core::convert::From`. pub const fn from_usize(v: usize) -> Status { Status(v) } /// Return Underlying Integer Representation /// /// This takes the `Status` object and returns the underlying integer representation as /// defined by the UEFI specification. pub const fn as_usize(&self) -> usize { self.0 } fn value(&self) -> usize { self.0 } fn mask(&self) -> usize { self.value() & Status::MASK } /// Check whether this is an error /// /// This returns true if the given status code is considered an error. Errors mean the /// operation did not succeed, nor produce any valuable output. Output parameters must be /// considered invalid if an error was returned. That is, its content is not well defined. pub fn is_error(&self) -> bool { self.mask() == Status::ERROR_MASK } /// Check whether this is a warning /// /// This returns true if the given status code is considered a warning. Warnings are to be /// treated as success, but might indicate data loss or other device errors. However, if an /// operation returns with a warning code, it must be considered successfull, and the output /// parameters are valid. pub fn is_warning(&self) -> bool { self.value() != 0 && self.mask() == Status::WARNING_MASK } } impl From for Result { fn from(status: Status) -> Self { if status.is_error() { Err(status) } else { Ok(status) } } } impl Guid { const fn u32_to_bytes_le(num: u32) -> [u8; 4] { [ num as u8, (num >> 8) as u8, (num >> 16) as u8, (num >> 24) as u8, ] } const fn u32_from_bytes_le(bytes: &[u8; 4]) -> u32 { (bytes[0] as u32) | ((bytes[1] as u32) << 8) | ((bytes[2] as u32) << 16) | ((bytes[3] as u32) << 24) } const fn u16_to_bytes_le(num: u16) -> [u8; 2] { [num as u8, (num >> 8) as u8] } const fn u16_from_bytes_le(bytes: &[u8; 2]) -> u16 { (bytes[0] as u16) | ((bytes[1] as u16) << 8) } /// Initialize a Guid from its individual fields /// /// This function initializes a Guid object given the individual fields as specified in the /// UEFI specification. That is, if you simply copy the literals from the specification into /// your code, this function will correctly initialize the Guid object. /// /// In other words, this takes the individual fields in native endian and converts them to the /// correct endianness for a UEFI Guid. pub const fn from_fields( time_low: u32, time_mid: u16, time_hi_and_version: u16, clk_seq_hi_res: u8, clk_seq_low: u8, node: &[u8; 6], ) -> Guid { Guid { time_low: Self::u32_to_bytes_le(time_low), time_mid: Self::u16_to_bytes_le(time_mid), time_hi_and_version: Self::u16_to_bytes_le(time_hi_and_version), clk_seq_hi_res: clk_seq_hi_res, clk_seq_low: clk_seq_low, node: *node, } } /// Access a Guid as individual fields /// /// This decomposes a Guid back into the individual fields as given in the specification. The /// individual fields are returned in native-endianness. pub const fn as_fields(&self) -> (u32, u16, u16, u8, u8, &[u8; 6]) { ( Self::u32_from_bytes_le(&self.time_low), Self::u16_from_bytes_le(&self.time_mid), Self::u16_from_bytes_le(&self.time_hi_and_version), self.clk_seq_hi_res, self.clk_seq_low, &self.node, ) } /// Access a Guid as raw byte array /// /// This provides access to a Guid through a byte array. It is a simple re-interpretation of /// the Guid value as a 128-bit byte array. No conversion is performed. This is a simple cast. pub fn as_bytes(&self) -> &[u8; 16] { unsafe { core::mem::transmute::<&Guid, &[u8; 16]>(self) } } } #[cfg(test)] mod tests { use super::*; use std::mem::{align_of, size_of}; // Verify Type Size and Alignemnt // // Since UEFI defines explicitly the ABI of their types, we can verify that our implementation // is correct by checking the size and alignment of the ABI types matches what the spec // mandates. #[test] fn type_size_and_alignment() { // // Booleans // assert_eq!(size_of::(), 1); assert_eq!(align_of::(), 1); // // Char8 / Char16 // assert_eq!(size_of::(), 1); assert_eq!(align_of::(), 1); assert_eq!(size_of::(), 2); assert_eq!(align_of::(), 2); assert_eq!(size_of::(), size_of::()); assert_eq!(align_of::(), align_of::()); assert_eq!(size_of::(), size_of::()); assert_eq!(align_of::(), align_of::()); // // Status // assert_eq!(size_of::(), size_of::()); assert_eq!(align_of::(), align_of::()); // // Handles / Events // assert_eq!(size_of::(), size_of::()); assert_eq!(align_of::(), align_of::()); assert_eq!(size_of::(), size_of::()); assert_eq!(align_of::(), align_of::()); assert_eq!(size_of::(), size_of::<*mut ()>()); assert_eq!(align_of::(), align_of::<*mut ()>()); assert_eq!(size_of::(), size_of::<*mut ()>()); assert_eq!(align_of::(), align_of::<*mut ()>()); // // Lba / Tpl // assert_eq!(size_of::(), size_of::()); assert_eq!(align_of::(), align_of::()); assert_eq!(size_of::(), size_of::()); assert_eq!(align_of::(), align_of::()); // // PhysicalAddress / VirtualAddress // assert_eq!(size_of::(), size_of::()); assert_eq!(align_of::(), align_of::()); assert_eq!(size_of::(), size_of::()); assert_eq!(align_of::(), align_of::()); // // ImageEntryPoint // assert_eq!(size_of::(), size_of::()); assert_eq!(align_of::(), align_of::()); // // Guid // assert_eq!(size_of::(), 16); assert_eq!(align_of::(), 8); // // Networking Types // assert_eq!(size_of::(), 32); assert_eq!(align_of::(), 1); assert_eq!(size_of::(), 4); assert_eq!(align_of::(), 1); assert_eq!(size_of::(), 16); assert_eq!(align_of::(), 1); assert_eq!(size_of::(), 16); assert_eq!(align_of::(), 4); } #[test] fn eficall() { // // Make sure the eficall!{} macro can deal with all kinds of function callbacks. // let _: eficall! {fn()}; let _: eficall! {unsafe fn()}; let _: eficall! {fn(i32)}; let _: eficall! {fn(i32) -> i32}; let _: eficall! {fn(i32, i32) -> (i32, i32)}; eficall! {fn _unused00() {}} eficall! {unsafe fn _unused01() {}} eficall! {pub unsafe fn _unused02() {}} } // Verify Boolean ABI // // Even though booleans are strictly 1-bit, and thus 0 or 1, in practice all UEFI systems // treat it more like C does, and a boolean formatted as `u8` now allows any value other than // 0 to represent `true`. Make sure we support the same. #[test] fn booleans() { // Verify PartialEq works. assert_ne!(Boolean::FALSE, Boolean::TRUE); // Verify Boolean<->bool conversion and comparison works. assert_eq!(Boolean::FALSE, false); assert_eq!(Boolean::TRUE, true); // Iterate all possible values for `u8` and verify 0 behaves as `false`, and everything // else behaves as `true`. We verify both, the natural constructor through `From`, as well // as a transmute. for i in 0u8..=255u8 { let v1: Boolean = i.into(); let v2: Boolean = unsafe { std::mem::transmute::(i) }; assert_eq!(v1, v2); assert_eq!(v1, v1); assert_eq!(v2, v2); match i { 0 => { assert_eq!(v1, Boolean::FALSE); assert_eq!(v1, false); assert_eq!(v2, Boolean::FALSE); assert_eq!(v2, false); assert_ne!(v1, Boolean::TRUE); assert_ne!(v1, true); assert_ne!(v2, Boolean::TRUE); assert_ne!(v2, true); } _ => { assert_eq!(v1, Boolean::TRUE); assert_eq!(v1, true); assert_eq!(v2, Boolean::TRUE); assert_eq!(v2, true); assert_ne!(v1, Boolean::FALSE); assert_ne!(v1, false); assert_ne!(v2, Boolean::FALSE); assert_ne!(v2, false); } } } } }