diff options
Diffstat (limited to 'third_party/rust/getrandom/src')
25 files changed, 1884 insertions, 0 deletions
diff --git a/third_party/rust/getrandom/src/3ds.rs b/third_party/rust/getrandom/src/3ds.rs new file mode 100644 index 0000000000..87a32a1e80 --- /dev/null +++ b/third_party/rust/getrandom/src/3ds.rs @@ -0,0 +1,18 @@ +// Copyright 2021 Developers of the Rand project. +// +// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or +// https://www.apache.org/licenses/LICENSE-2.0> or the MIT license +// <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +//! Implementation for Nintendo 3DS +use crate::util_libc::sys_fill_exact; +use crate::Error; +use core::mem::MaybeUninit; + +pub fn getrandom_inner(dest: &mut [MaybeUninit<u8>]) -> Result<(), Error> { + sys_fill_exact(dest, |buf| unsafe { + libc::getrandom(buf.as_mut_ptr() as *mut libc::c_void, buf.len(), 0) + }) +} diff --git a/third_party/rust/getrandom/src/apple-other.rs b/third_party/rust/getrandom/src/apple-other.rs new file mode 100644 index 0000000000..8f904859ca --- /dev/null +++ b/third_party/rust/getrandom/src/apple-other.rs @@ -0,0 +1,27 @@ +// Copyright 2018 Developers of the Rand project. +// +// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or +// https://www.apache.org/licenses/LICENSE-2.0> or the MIT license +// <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +//! Implementation for iOS +use crate::Error; +use core::{ffi::c_void, mem::MaybeUninit, ptr::null}; + +#[link(name = "Security", kind = "framework")] +extern "C" { + fn SecRandomCopyBytes(rnd: *const c_void, count: usize, bytes: *mut u8) -> i32; +} + +pub fn getrandom_inner(dest: &mut [MaybeUninit<u8>]) -> Result<(), Error> { + // Apple's documentation guarantees kSecRandomDefault is a synonym for NULL. + let ret = unsafe { SecRandomCopyBytes(null(), dest.len(), dest.as_mut_ptr() as *mut u8) }; + // errSecSuccess (from SecBase.h) is always zero. + if ret != 0 { + Err(Error::IOS_SEC_RANDOM) + } else { + Ok(()) + } +} diff --git a/third_party/rust/getrandom/src/bsd_arandom.rs b/third_party/rust/getrandom/src/bsd_arandom.rs new file mode 100644 index 0000000000..5314c48f19 --- /dev/null +++ b/third_party/rust/getrandom/src/bsd_arandom.rs @@ -0,0 +1,54 @@ +// Copyright 2018 Developers of the Rand project. +// +// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or +// https://www.apache.org/licenses/LICENSE-2.0> or the MIT license +// <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +//! Implementation for FreeBSD and NetBSD +use crate::{ + util_libc::{sys_fill_exact, Weak}, + Error, +}; +use core::{mem::MaybeUninit, ptr}; + +fn kern_arnd(buf: &mut [MaybeUninit<u8>]) -> libc::ssize_t { + static MIB: [libc::c_int; 2] = [libc::CTL_KERN, libc::KERN_ARND]; + let mut len = buf.len(); + let ret = unsafe { + libc::sysctl( + MIB.as_ptr(), + MIB.len() as libc::c_uint, + buf.as_mut_ptr() as *mut _, + &mut len, + ptr::null(), + 0, + ) + }; + if ret == -1 { + -1 + } else { + len as libc::ssize_t + } +} + +type GetRandomFn = unsafe extern "C" fn(*mut u8, libc::size_t, libc::c_uint) -> libc::ssize_t; + +pub fn getrandom_inner(dest: &mut [MaybeUninit<u8>]) -> Result<(), Error> { + // getrandom(2) was introduced in FreeBSD 12.0 and NetBSD 10.0 + static GETRANDOM: Weak = unsafe { Weak::new("getrandom\0") }; + if let Some(fptr) = GETRANDOM.ptr() { + let func: GetRandomFn = unsafe { core::mem::transmute(fptr) }; + return sys_fill_exact(dest, |buf| unsafe { + func(buf.as_mut_ptr() as *mut u8, buf.len(), 0) + }); + } + + // Both FreeBSD and NetBSD will only return up to 256 bytes at a time, and + // older NetBSD kernels will fail on longer buffers. + for chunk in dest.chunks_mut(256) { + sys_fill_exact(chunk, kern_arnd)? + } + Ok(()) +} diff --git a/third_party/rust/getrandom/src/custom.rs b/third_party/rust/getrandom/src/custom.rs new file mode 100644 index 0000000000..c9207d0613 --- /dev/null +++ b/third_party/rust/getrandom/src/custom.rs @@ -0,0 +1,114 @@ +// Copyright 2018 Developers of the Rand project. +// +// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or +// https://www.apache.org/licenses/LICENSE-2.0> or the MIT license +// <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +//! An implementation which calls out to an externally defined function. +use crate::{util::uninit_slice_fill_zero, Error}; +use core::{mem::MaybeUninit, num::NonZeroU32}; + +/// Register a function to be invoked by `getrandom` on unsupported targets. +/// +/// ## Writing a custom `getrandom` implementation +/// +/// The function to register must have the same signature as +/// [`getrandom::getrandom`](crate::getrandom). The function can be defined +/// wherever you want, either in root crate or a dependent crate. +/// +/// For example, if we wanted a `failure-getrandom` crate containing an +/// implementation that always fails, we would first depend on `getrandom` +/// (for the [`Error`] type) in `failure-getrandom/Cargo.toml`: +/// ```toml +/// [dependencies] +/// getrandom = "0.2" +/// ``` +/// Note that the crate containing this function does **not** need to enable the +/// `"custom"` Cargo feature. +/// +/// Next, in `failure-getrandom/src/lib.rs`, we define our function: +/// ```rust +/// use core::num::NonZeroU32; +/// use getrandom::Error; +/// +/// // Some application-specific error code +/// const MY_CUSTOM_ERROR_CODE: u32 = Error::CUSTOM_START + 42; +/// pub fn always_fail(buf: &mut [u8]) -> Result<(), Error> { +/// let code = NonZeroU32::new(MY_CUSTOM_ERROR_CODE).unwrap(); +/// Err(Error::from(code)) +/// } +/// ``` +/// +/// ## Registering a custom `getrandom` implementation +/// +/// Functions can only be registered in the root binary crate. Attempting to +/// register a function in a non-root crate will result in a linker error. +/// This is similar to +/// [`#[panic_handler]`](https://doc.rust-lang.org/nomicon/panic-handler.html) or +/// [`#[global_allocator]`](https://doc.rust-lang.org/edition-guide/rust-2018/platform-and-target-support/global-allocators.html), +/// where helper crates define handlers/allocators but only the binary crate +/// actually _uses_ the functionality. +/// +/// To register the function, we first depend on `failure-getrandom` _and_ +/// `getrandom` in `Cargo.toml`: +/// ```toml +/// [dependencies] +/// failure-getrandom = "0.1" +/// getrandom = { version = "0.2", features = ["custom"] } +/// ``` +/// +/// Then, we register the function in `src/main.rs`: +/// ```rust +/// # mod failure_getrandom { pub fn always_fail(_: &mut [u8]) -> Result<(), getrandom::Error> { unimplemented!() } } +/// use failure_getrandom::always_fail; +/// use getrandom::register_custom_getrandom; +/// +/// register_custom_getrandom!(always_fail); +/// ``` +/// +/// Now any user of `getrandom` (direct or indirect) on this target will use the +/// registered function. As noted in the +/// [top-level documentation](index.html#custom-implementations) this +/// registration only has an effect on unsupported targets. +#[macro_export] +#[cfg_attr(docsrs, doc(cfg(feature = "custom")))] +macro_rules! register_custom_getrandom { + ($path:path) => { + // TODO(MSRV 1.37): change to unnamed block + const __getrandom_internal: () = { + // We use Rust ABI to be safe against potential panics in the passed function. + #[no_mangle] + unsafe fn __getrandom_custom(dest: *mut u8, len: usize) -> u32 { + // Make sure the passed function has the type of getrandom::getrandom + type F = fn(&mut [u8]) -> ::core::result::Result<(), $crate::Error>; + let _: F = $crate::getrandom; + let f: F = $path; + let slice = ::core::slice::from_raw_parts_mut(dest, len); + match f(slice) { + Ok(()) => 0, + Err(e) => e.code().get(), + } + } + }; + }; +} + +#[allow(dead_code)] +pub fn getrandom_inner(dest: &mut [MaybeUninit<u8>]) -> Result<(), Error> { + extern "Rust" { + fn __getrandom_custom(dest: *mut u8, len: usize) -> u32; + } + // Previously we always passed a valid, initialized slice to + // `__getrandom_custom`. Ensure `dest` has been initialized for backward + // compatibility with implementations that rely on that (e.g. Rust + // implementations that construct a `&mut [u8]` slice from `dest` and + // `len`). + let dest = uninit_slice_fill_zero(dest); + let ret = unsafe { __getrandom_custom(dest.as_mut_ptr(), dest.len()) }; + match NonZeroU32::new(ret) { + None => Ok(()), + Some(code) => Err(Error::from(code)), + } +} diff --git a/third_party/rust/getrandom/src/dragonfly.rs b/third_party/rust/getrandom/src/dragonfly.rs new file mode 100644 index 0000000000..d3ef00aa9c --- /dev/null +++ b/third_party/rust/getrandom/src/dragonfly.rs @@ -0,0 +1,30 @@ +// Copyright 2021 Developers of the Rand project. +// +// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or +// https://www.apache.org/licenses/LICENSE-2.0> or the MIT license +// <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +//! Implementation for DragonFly BSD +use crate::{ + use_file, + util_libc::{sys_fill_exact, Weak}, + Error, +}; +use core::mem::MaybeUninit; + +pub fn getrandom_inner(dest: &mut [MaybeUninit<u8>]) -> Result<(), Error> { + static GETRANDOM: Weak = unsafe { Weak::new("getrandom\0") }; + type GetRandomFn = unsafe extern "C" fn(*mut u8, libc::size_t, libc::c_uint) -> libc::ssize_t; + + // getrandom(2) was introduced in DragonflyBSD 5.7 + if let Some(fptr) = GETRANDOM.ptr() { + let func: GetRandomFn = unsafe { core::mem::transmute(fptr) }; + return sys_fill_exact(dest, |buf| unsafe { + func(buf.as_mut_ptr() as *mut u8, buf.len(), 0) + }); + } else { + use_file::getrandom_inner(dest) + } +} diff --git a/third_party/rust/getrandom/src/emscripten.rs b/third_party/rust/getrandom/src/emscripten.rs new file mode 100644 index 0000000000..a50372f566 --- /dev/null +++ b/third_party/rust/getrandom/src/emscripten.rs @@ -0,0 +1,18 @@ +//! Implementation for Emscripten +use crate::{util_libc::last_os_error, Error}; +use core::mem::MaybeUninit; + +// Not yet defined in libc crate. +extern "C" { + fn getentropy(buffer: *mut libc::c_void, length: usize) -> libc::c_int; +} + +pub fn getrandom_inner(dest: &mut [MaybeUninit<u8>]) -> Result<(), Error> { + // Emscripten 2.0.5 added getentropy, so we can use it unconditionally. + // Unlike other getentropy implementations, there is no max buffer length. + let ret = unsafe { getentropy(dest.as_mut_ptr() as *mut libc::c_void, dest.len()) }; + if ret < 0 { + return Err(last_os_error()); + } + Ok(()) +} diff --git a/third_party/rust/getrandom/src/error.rs b/third_party/rust/getrandom/src/error.rs new file mode 100644 index 0000000000..ab39a3c33a --- /dev/null +++ b/third_party/rust/getrandom/src/error.rs @@ -0,0 +1,191 @@ +// Copyright 2018 Developers of the Rand project. +// +// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or +// https://www.apache.org/licenses/LICENSE-2.0> or the MIT license +// <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. +use core::{fmt, num::NonZeroU32}; + +/// A small and `no_std` compatible error type +/// +/// The [`Error::raw_os_error()`] will indicate if the error is from the OS, and +/// if so, which error code the OS gave the application. If such an error is +/// encountered, please consult with your system documentation. +/// +/// Internally this type is a NonZeroU32, with certain values reserved for +/// certain purposes, see [`Error::INTERNAL_START`] and [`Error::CUSTOM_START`]. +/// +/// *If this crate's `"std"` Cargo feature is enabled*, then: +/// - [`getrandom::Error`][Error] implements +/// [`std::error::Error`](https://doc.rust-lang.org/std/error/trait.Error.html) +/// - [`std::io::Error`](https://doc.rust-lang.org/std/io/struct.Error.html) implements +/// [`From<getrandom::Error>`](https://doc.rust-lang.org/std/convert/trait.From.html). +#[derive(Copy, Clone, Eq, PartialEq)] +pub struct Error(NonZeroU32); + +const fn internal_error(n: u16) -> Error { + // SAFETY: code > 0 as INTERNAL_START > 0 and adding n won't overflow a u32. + let code = Error::INTERNAL_START + (n as u32); + Error(unsafe { NonZeroU32::new_unchecked(code) }) +} + +impl Error { + /// This target/platform is not supported by `getrandom`. + pub const UNSUPPORTED: Error = internal_error(0); + /// The platform-specific `errno` returned a non-positive value. + pub const ERRNO_NOT_POSITIVE: Error = internal_error(1); + /// Call to iOS [`SecRandomCopyBytes`](https://developer.apple.com/documentation/security/1399291-secrandomcopybytes) failed. + pub const IOS_SEC_RANDOM: Error = internal_error(3); + /// Call to Windows [`RtlGenRandom`](https://docs.microsoft.com/en-us/windows/win32/api/ntsecapi/nf-ntsecapi-rtlgenrandom) failed. + pub const WINDOWS_RTL_GEN_RANDOM: Error = internal_error(4); + /// RDRAND instruction failed due to a hardware issue. + pub const FAILED_RDRAND: Error = internal_error(5); + /// RDRAND instruction unsupported on this target. + pub const NO_RDRAND: Error = internal_error(6); + /// The environment does not support the Web Crypto API. + pub const WEB_CRYPTO: Error = internal_error(7); + /// Calling Web Crypto API `crypto.getRandomValues` failed. + pub const WEB_GET_RANDOM_VALUES: Error = internal_error(8); + /// On VxWorks, call to `randSecure` failed (random number generator is not yet initialized). + pub const VXWORKS_RAND_SECURE: Error = internal_error(11); + /// Node.js does not have the `crypto` CommonJS module. + pub const NODE_CRYPTO: Error = internal_error(12); + /// Calling Node.js function `crypto.randomFillSync` failed. + pub const NODE_RANDOM_FILL_SYNC: Error = internal_error(13); + /// Called from an ES module on Node.js. This is unsupported, see: + /// <https://docs.rs/getrandom#nodejs-es-module-support>. + pub const NODE_ES_MODULE: Error = internal_error(14); + + /// Codes below this point represent OS Errors (i.e. positive i32 values). + /// Codes at or above this point, but below [`Error::CUSTOM_START`] are + /// reserved for use by the `rand` and `getrandom` crates. + pub const INTERNAL_START: u32 = 1 << 31; + + /// Codes at or above this point can be used by users to define their own + /// custom errors. + pub const CUSTOM_START: u32 = (1 << 31) + (1 << 30); + + /// Extract the raw OS error code (if this error came from the OS) + /// + /// This method is identical to [`std::io::Error::raw_os_error()`][1], except + /// that it works in `no_std` contexts. If this method returns `None`, the + /// error value can still be formatted via the `Display` implementation. + /// + /// [1]: https://doc.rust-lang.org/std/io/struct.Error.html#method.raw_os_error + #[inline] + pub fn raw_os_error(self) -> Option<i32> { + if self.0.get() < Self::INTERNAL_START { + match () { + #[cfg(target_os = "solid_asp3")] + // On SOLID, negate the error code again to obtain the original + // error code. + () => Some(-(self.0.get() as i32)), + #[cfg(not(target_os = "solid_asp3"))] + () => Some(self.0.get() as i32), + } + } else { + None + } + } + + /// Extract the bare error code. + /// + /// This code can either come from the underlying OS, or be a custom error. + /// Use [`Error::raw_os_error()`] to disambiguate. + #[inline] + pub const fn code(self) -> NonZeroU32 { + self.0 + } +} + +cfg_if! { + if #[cfg(unix)] { + fn os_err(errno: i32, buf: &mut [u8]) -> Option<&str> { + let buf_ptr = buf.as_mut_ptr() as *mut libc::c_char; + if unsafe { libc::strerror_r(errno, buf_ptr, buf.len()) } != 0 { + return None; + } + + // Take up to trailing null byte + let n = buf.len(); + let idx = buf.iter().position(|&b| b == 0).unwrap_or(n); + core::str::from_utf8(&buf[..idx]).ok() + } + } else { + fn os_err(_errno: i32, _buf: &mut [u8]) -> Option<&str> { + None + } + } +} + +impl fmt::Debug for Error { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + let mut dbg = f.debug_struct("Error"); + if let Some(errno) = self.raw_os_error() { + dbg.field("os_error", &errno); + let mut buf = [0u8; 128]; + if let Some(err) = os_err(errno, &mut buf) { + dbg.field("description", &err); + } + } else if let Some(desc) = internal_desc(*self) { + dbg.field("internal_code", &self.0.get()); + dbg.field("description", &desc); + } else { + dbg.field("unknown_code", &self.0.get()); + } + dbg.finish() + } +} + +impl fmt::Display for Error { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + if let Some(errno) = self.raw_os_error() { + let mut buf = [0u8; 128]; + match os_err(errno, &mut buf) { + Some(err) => err.fmt(f), + None => write!(f, "OS Error: {}", errno), + } + } else if let Some(desc) = internal_desc(*self) { + f.write_str(desc) + } else { + write!(f, "Unknown Error: {}", self.0.get()) + } + } +} + +impl From<NonZeroU32> for Error { + fn from(code: NonZeroU32) -> Self { + Self(code) + } +} + +fn internal_desc(error: Error) -> Option<&'static str> { + match error { + Error::UNSUPPORTED => Some("getrandom: this target is not supported"), + Error::ERRNO_NOT_POSITIVE => Some("errno: did not return a positive value"), + Error::IOS_SEC_RANDOM => Some("SecRandomCopyBytes: iOS Security framework failure"), + Error::WINDOWS_RTL_GEN_RANDOM => Some("RtlGenRandom: Windows system function failure"), + Error::FAILED_RDRAND => Some("RDRAND: failed multiple times: CPU issue likely"), + Error::NO_RDRAND => Some("RDRAND: instruction not supported"), + Error::WEB_CRYPTO => Some("Web Crypto API is unavailable"), + Error::WEB_GET_RANDOM_VALUES => Some("Calling Web API crypto.getRandomValues failed"), + Error::VXWORKS_RAND_SECURE => Some("randSecure: VxWorks RNG module is not initialized"), + Error::NODE_CRYPTO => Some("Node.js crypto CommonJS module is unavailable"), + Error::NODE_RANDOM_FILL_SYNC => Some("Calling Node.js API crypto.randomFillSync failed"), + Error::NODE_ES_MODULE => Some("Node.js ES modules are not directly supported, see https://docs.rs/getrandom#nodejs-es-module-support"), + _ => None, + } +} + +#[cfg(test)] +mod tests { + use super::Error; + use core::mem::size_of; + + #[test] + fn test_size() { + assert_eq!(size_of::<Error>(), 4); + assert_eq!(size_of::<Result<(), Error>>(), 4); + } +} diff --git a/third_party/rust/getrandom/src/error_impls.rs b/third_party/rust/getrandom/src/error_impls.rs new file mode 100644 index 0000000000..61f46d2279 --- /dev/null +++ b/third_party/rust/getrandom/src/error_impls.rs @@ -0,0 +1,24 @@ +// Copyright 2018 Developers of the Rand project. +// +// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or +// https://www.apache.org/licenses/LICENSE-2.0> or the MIT license +// <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. +#![cfg_attr(docsrs, doc(cfg(feature = "std")))] +extern crate std; + +use crate::Error; +use core::convert::From; +use std::io; + +impl From<Error> for io::Error { + fn from(err: Error) -> Self { + match err.raw_os_error() { + Some(errno) => io::Error::from_raw_os_error(errno), + None => io::Error::new(io::ErrorKind::Other, err), + } + } +} + +impl std::error::Error for Error {} diff --git a/third_party/rust/getrandom/src/espidf.rs b/third_party/rust/getrandom/src/espidf.rs new file mode 100644 index 0000000000..d074dc4cec --- /dev/null +++ b/third_party/rust/getrandom/src/espidf.rs @@ -0,0 +1,26 @@ +// Copyright 2021 Developers of the Rand project. +// +// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or +// https://www.apache.org/licenses/LICENSE-2.0> or the MIT license +// <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +//! Implementation for ESP-IDF +use crate::Error; +use core::{ffi::c_void, mem::MaybeUninit}; + +extern "C" { + fn esp_fill_random(buf: *mut c_void, len: usize) -> u32; +} + +pub fn getrandom_inner(dest: &mut [MaybeUninit<u8>]) -> Result<(), Error> { + // Not that NOT enabling WiFi, BT, or the voltage noise entropy source (via `bootloader_random_enable`) + // will cause ESP-IDF to return pseudo-random numbers based on the voltage noise entropy, after the initial boot process: + // https://docs.espressif.com/projects/esp-idf/en/latest/esp32/api-reference/system/random.html + // + // However tracking if some of these entropy sources is enabled is way too difficult to implement here + unsafe { esp_fill_random(dest.as_mut_ptr().cast(), dest.len()) }; + + Ok(()) +} diff --git a/third_party/rust/getrandom/src/fuchsia.rs b/third_party/rust/getrandom/src/fuchsia.rs new file mode 100644 index 0000000000..5a135f3430 --- /dev/null +++ b/third_party/rust/getrandom/src/fuchsia.rs @@ -0,0 +1,21 @@ +// Copyright 2018 Developers of the Rand project. +// +// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or +// https://www.apache.org/licenses/LICENSE-2.0> or the MIT license +// <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +//! Implementation for Fuchsia Zircon +use crate::Error; +use core::mem::MaybeUninit; + +#[link(name = "zircon")] +extern "C" { + fn zx_cprng_draw(buffer: *mut u8, length: usize); +} + +pub fn getrandom_inner(dest: &mut [MaybeUninit<u8>]) -> Result<(), Error> { + unsafe { zx_cprng_draw(dest.as_mut_ptr() as *mut u8, dest.len()) } + Ok(()) +} diff --git a/third_party/rust/getrandom/src/hermit.rs b/third_party/rust/getrandom/src/hermit.rs new file mode 100644 index 0000000000..570b03d9a5 --- /dev/null +++ b/third_party/rust/getrandom/src/hermit.rs @@ -0,0 +1,21 @@ +use crate::Error; +use core::{cmp::min, mem::MaybeUninit, num::NonZeroU32}; + +extern "C" { + fn sys_read_entropy(buffer: *mut u8, length: usize, flags: u32) -> isize; +} + +pub fn getrandom_inner(mut dest: &mut [MaybeUninit<u8>]) -> Result<(), Error> { + while !dest.is_empty() { + let res = unsafe { sys_read_entropy(dest.as_mut_ptr() as *mut u8, dest.len(), 0) }; + if res < 0 { + // SAFETY: all Hermit error codes use i32 under the hood: + // https://github.com/hermitcore/libhermit-rs/blob/master/src/errno.rs + let code = unsafe { NonZeroU32::new_unchecked((-res) as u32) }; + return Err(code.into()); + } + let len = min(res as usize, dest.len()); + dest = &mut dest[len..]; + } + Ok(()) +} diff --git a/third_party/rust/getrandom/src/js.rs b/third_party/rust/getrandom/src/js.rs new file mode 100644 index 0000000000..d031282261 --- /dev/null +++ b/third_party/rust/getrandom/src/js.rs @@ -0,0 +1,161 @@ +// Copyright 2018 Developers of the Rand project. +// +// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or +// https://www.apache.org/licenses/LICENSE-2.0> or the MIT license +// <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. +use crate::Error; + +extern crate std; +use std::{mem::MaybeUninit, thread_local}; + +use js_sys::{global, Function, Uint8Array}; +use wasm_bindgen::{prelude::wasm_bindgen, JsCast, JsValue}; + +// Size of our temporary Uint8Array buffer used with WebCrypto methods +// Maximum is 65536 bytes see https://developer.mozilla.org/en-US/docs/Web/API/Crypto/getRandomValues +const WEB_CRYPTO_BUFFER_SIZE: usize = 256; +// Node.js's crypto.randomFillSync requires the size to be less than 2**31. +const NODE_MAX_BUFFER_SIZE: usize = (1 << 31) - 1; + +enum RngSource { + Node(NodeCrypto), + Web(WebCrypto, Uint8Array), +} + +// JsValues are always per-thread, so we initialize RngSource for each thread. +// See: https://github.com/rustwasm/wasm-bindgen/pull/955 +thread_local!( + static RNG_SOURCE: Result<RngSource, Error> = getrandom_init(); +); + +pub(crate) fn getrandom_inner(dest: &mut [MaybeUninit<u8>]) -> Result<(), Error> { + RNG_SOURCE.with(|result| { + let source = result.as_ref().map_err(|&e| e)?; + + match source { + RngSource::Node(n) => { + for chunk in dest.chunks_mut(NODE_MAX_BUFFER_SIZE) { + // SAFETY: chunk is never used directly, the memory is only + // modified via the Uint8Array view, which is passed + // directly to JavaScript. Also, crypto.randomFillSync does + // not resize the buffer. We know the length is less than + // u32::MAX because of the chunking above. + // Note that this uses the fact that JavaScript doesn't + // have a notion of "uninitialized memory", this is purely + // a Rust/C/C++ concept. + let res = n.random_fill_sync(unsafe { + Uint8Array::view_mut_raw(chunk.as_mut_ptr() as *mut u8, chunk.len()) + }); + if res.is_err() { + return Err(Error::NODE_RANDOM_FILL_SYNC); + } + } + } + RngSource::Web(crypto, buf) => { + // getRandomValues does not work with all types of WASM memory, + // so we initially write to browser memory to avoid exceptions. + for chunk in dest.chunks_mut(WEB_CRYPTO_BUFFER_SIZE) { + // The chunk can be smaller than buf's length, so we call to + // JS to create a smaller view of buf without allocation. + let sub_buf = buf.subarray(0, chunk.len() as u32); + + if crypto.get_random_values(&sub_buf).is_err() { + return Err(Error::WEB_GET_RANDOM_VALUES); + } + + // SAFETY: `sub_buf`'s length is the same length as `chunk` + unsafe { sub_buf.raw_copy_to_ptr(chunk.as_mut_ptr() as *mut u8) }; + } + } + }; + Ok(()) + }) +} + +fn getrandom_init() -> Result<RngSource, Error> { + let global: Global = global().unchecked_into(); + + // Get the Web Crypto interface if we are in a browser, Web Worker, Deno, + // or another environment that supports the Web Cryptography API. This + // also allows for user-provided polyfills in unsupported environments. + let crypto = match global.crypto() { + // Standard Web Crypto interface + c if c.is_object() => c, + // Node.js CommonJS Crypto module + _ if is_node(&global) => { + // If module.require isn't a valid function, we are in an ES module. + match Module::require_fn().and_then(JsCast::dyn_into::<Function>) { + Ok(require_fn) => match require_fn.call1(&global, &JsValue::from_str("crypto")) { + Ok(n) => return Ok(RngSource::Node(n.unchecked_into())), + Err(_) => return Err(Error::NODE_CRYPTO), + }, + Err(_) => return Err(Error::NODE_ES_MODULE), + } + } + // IE 11 Workaround + _ => match global.ms_crypto() { + c if c.is_object() => c, + _ => return Err(Error::WEB_CRYPTO), + }, + }; + + let buf = Uint8Array::new_with_length(WEB_CRYPTO_BUFFER_SIZE as u32); + Ok(RngSource::Web(crypto, buf)) +} + +// Taken from https://www.npmjs.com/package/browser-or-node +fn is_node(global: &Global) -> bool { + let process = global.process(); + if process.is_object() { + let versions = process.versions(); + if versions.is_object() { + return versions.node().is_string(); + } + } + false +} + +#[wasm_bindgen] +extern "C" { + // Return type of js_sys::global() + type Global; + + // Web Crypto API: Crypto interface (https://www.w3.org/TR/WebCryptoAPI/) + type WebCrypto; + // Getters for the WebCrypto API + #[wasm_bindgen(method, getter)] + fn crypto(this: &Global) -> WebCrypto; + #[wasm_bindgen(method, getter, js_name = msCrypto)] + fn ms_crypto(this: &Global) -> WebCrypto; + // Crypto.getRandomValues() + #[wasm_bindgen(method, js_name = getRandomValues, catch)] + fn get_random_values(this: &WebCrypto, buf: &Uint8Array) -> Result<(), JsValue>; + + // Node JS crypto module (https://nodejs.org/api/crypto.html) + type NodeCrypto; + // crypto.randomFillSync() + #[wasm_bindgen(method, js_name = randomFillSync, catch)] + fn random_fill_sync(this: &NodeCrypto, buf: Uint8Array) -> Result<(), JsValue>; + + // Ideally, we would just use `fn require(s: &str)` here. However, doing + // this causes a Webpack warning. So we instead return the function itself + // and manually invoke it using call1. This also lets us to check that the + // function actually exists, allowing for better error messages. See: + // https://github.com/rust-random/getrandom/issues/224 + // https://github.com/rust-random/getrandom/issues/256 + type Module; + #[wasm_bindgen(getter, static_method_of = Module, js_class = module, js_name = require, catch)] + fn require_fn() -> Result<JsValue, JsValue>; + + // Node JS process Object (https://nodejs.org/api/process.html) + #[wasm_bindgen(method, getter)] + fn process(this: &Global) -> Process; + type Process; + #[wasm_bindgen(method, getter)] + fn versions(this: &Process) -> Versions; + type Versions; + #[wasm_bindgen(method, getter)] + fn node(this: &Versions) -> JsValue; +} diff --git a/third_party/rust/getrandom/src/lib.rs b/third_party/rust/getrandom/src/lib.rs new file mode 100644 index 0000000000..931856f703 --- /dev/null +++ b/third_party/rust/getrandom/src/lib.rs @@ -0,0 +1,342 @@ +// Copyright 2019 Developers of the Rand project. +// +// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or +// https://www.apache.org/licenses/LICENSE-2.0> or the MIT license +// <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +//! Interface to the operating system's random number generator. +//! +//! # Supported targets +//! +//! | Target | Target Triple | Implementation +//! | ----------------- | ------------------ | -------------- +//! | Linux, Android | `*‑linux‑*` | [`getrandom`][1] system call if available, otherwise [`/dev/urandom`][2] after successfully polling `/dev/random` +//! | Windows | `*‑windows‑*` | [`BCryptGenRandom`] +//! | macOS | `*‑apple‑darwin` | [`getentropy`][3] if available, otherwise [`/dev/urandom`][4] (identical to `/dev/random`) +//! | iOS, tvOS, watchOS | `*‑apple‑ios`, `*-apple-tvos`, `*-apple-watchos` | [`SecRandomCopyBytes`] +//! | FreeBSD | `*‑freebsd` | [`getrandom`][5] if available, otherwise [`kern.arandom`][6] +//! | OpenBSD | `*‑openbsd` | [`getentropy`][7] +//! | NetBSD | `*‑netbsd` | [`getrandom`][16] if available, otherwise [`kern.arandom`][8] +//! | Dragonfly BSD | `*‑dragonfly` | [`getrandom`][9] if available, otherwise [`/dev/urandom`][10] (identical to `/dev/random`) +//! | Solaris, illumos | `*‑solaris`, `*‑illumos` | [`getrandom`][11] if available, otherwise [`/dev/random`][12] +//! | Fuchsia OS | `*‑fuchsia` | [`cprng_draw`] +//! | Redox | `*‑redox` | `/dev/urandom` +//! | Haiku | `*‑haiku` | `/dev/urandom` (identical to `/dev/random`) +//! | Hermit | `*-hermit` | [`sys_read_entropy`] +//! | SGX | `x86_64‑*‑sgx` | [`RDRAND`] +//! | VxWorks | `*‑wrs‑vxworks‑*` | `randABytes` after checking entropy pool initialization with `randSecure` +//! | ESP-IDF | `*‑espidf` | [`esp_fill_random`] +//! | Emscripten | `*‑emscripten` | [`getentropy`][13] +//! | WASI | `wasm32‑wasi` | [`random_get`] +//! | Web Browser and Node.js | `wasm*‑*‑unknown` | [`Crypto.getRandomValues`] if available, then [`crypto.randomFillSync`] if on Node.js, see [WebAssembly support] +//! | SOLID | `*-kmc-solid_*` | `SOLID_RNG_SampleRandomBytes` +//! | Nintendo 3DS | `armv6k-nintendo-3ds` | [`getrandom`][1] +//! | QNX Neutrino | `*‑nto-qnx*` | [`/dev/urandom`][14] (identical to `/dev/random`) +//! | AIX | `*-ibm-aix` | [`/dev/urandom`][15] +//! +//! There is no blanket implementation on `unix` targets that reads from +//! `/dev/urandom`. This ensures all supported targets are using the recommended +//! interface and respect maximum buffer sizes. +//! +//! Pull Requests that add support for new targets to `getrandom` are always welcome. +//! +//! ## Unsupported targets +//! +//! By default, `getrandom` will not compile on unsupported targets, but certain +//! features allow a user to select a "fallback" implementation if no supported +//! implementation exists. +//! +//! All of the below mechanisms only affect unsupported +//! targets. Supported targets will _always_ use their supported implementations. +//! This prevents a crate from overriding a secure source of randomness +//! (either accidentally or intentionally). +//! +//! ### RDRAND on x86 +//! +//! *If the `rdrand` Cargo feature is enabled*, `getrandom` will fallback to using +//! the [`RDRAND`] instruction to get randomness on `no_std` `x86`/`x86_64` +//! targets. This feature has no effect on other CPU architectures. +//! +//! ### WebAssembly support +//! +//! This crate fully supports the +//! [`wasm32-wasi`](https://github.com/CraneStation/wasi) and +//! [`wasm32-unknown-emscripten`](https://www.hellorust.com/setup/emscripten/) +//! targets. However, the `wasm32-unknown-unknown` target (i.e. the target used +//! by `wasm-pack`) is not automatically +//! supported since, from the target name alone, we cannot deduce which +//! JavaScript interface is in use (or if JavaScript is available at all). +//! +//! Instead, *if the `js` Cargo feature is enabled*, this crate will assume +//! that you are building for an environment containing JavaScript, and will +//! call the appropriate methods. Both web browser (main window and Web Workers) +//! and Node.js environments are supported, invoking the methods +//! [described above](#supported-targets) using the [`wasm-bindgen`] toolchain. +//! +//! To enable the `js` Cargo feature, add the following to the `dependencies` +//! section in your `Cargo.toml` file: +//! ```toml +//! [dependencies] +//! getrandom = { version = "0.2", features = ["js"] } +//! ``` +//! +//! This can be done even if `getrandom` is not a direct dependency. Cargo +//! allows crates to enable features for indirect dependencies. +//! +//! This feature should only be enabled for binary, test, or benchmark crates. +//! Library crates should generally not enable this feature, leaving such a +//! decision to *users* of their library. Also, libraries should not introduce +//! their own `js` features *just* to enable `getrandom`'s `js` feature. +//! +//! This feature has no effect on targets other than `wasm32-unknown-unknown`. +//! +//! #### Node.js ES module support +//! +//! Node.js supports both [CommonJS modules] and [ES modules]. Due to +//! limitations in wasm-bindgen's [`module`] support, we cannot directly +//! support ES Modules running on Node.js. However, on Node v15 and later, the +//! module author can add a simple shim to support the Web Cryptography API: +//! ```js +//! import { webcrypto } from 'node:crypto' +//! globalThis.crypto = webcrypto +//! ``` +//! This crate will then use the provided `webcrypto` implementation. +//! +//! ### Custom implementations +//! +//! The [`register_custom_getrandom!`] macro allows a user to mark their own +//! function as the backing implementation for [`getrandom`]. See the macro's +//! documentation for more information about writing and registering your own +//! custom implementations. +//! +//! Note that registering a custom implementation only has an effect on targets +//! that would otherwise not compile. Any supported targets (including those +//! using `rdrand` and `js` Cargo features) continue using their normal +//! implementations even if a function is registered. +//! +//! ## Early boot +//! +//! Sometimes, early in the boot process, the OS has not collected enough +//! entropy to securely seed its RNG. This is especially common on virtual +//! machines, where standard "random" events are hard to come by. +//! +//! Some operating system interfaces always block until the RNG is securely +//! seeded. This can take anywhere from a few seconds to more than a minute. +//! A few (Linux, NetBSD and Solaris) offer a choice between blocking and +//! getting an error; in these cases, we always choose to block. +//! +//! On Linux (when the `getrandom` system call is not available), reading from +//! `/dev/urandom` never blocks, even when the OS hasn't collected enough +//! entropy yet. To avoid returning low-entropy bytes, we first poll +//! `/dev/random` and only switch to `/dev/urandom` once this has succeeded. +//! +//! On OpenBSD, this kind of entropy accounting isn't available, and on +//! NetBSD, blocking on it is discouraged. On these platforms, nonblocking +//! interfaces are used, even when reliable entropy may not be available. +//! On the platforms where it is used, the reliability of entropy accounting +//! itself isn't free from controversy. This library provides randomness +//! sourced according to the platform's best practices, but each platform has +//! its own limits on the grade of randomness it can promise in environments +//! with few sources of entropy. +//! +//! ## Error handling +//! +//! We always choose failure over returning known insecure "random" bytes. In +//! general, on supported platforms, failure is highly unlikely, though not +//! impossible. If an error does occur, then it is likely that it will occur +//! on every call to `getrandom`, hence after the first successful call one +//! can be reasonably confident that no errors will occur. +//! +//! [1]: http://man7.org/linux/man-pages/man2/getrandom.2.html +//! [2]: http://man7.org/linux/man-pages/man4/urandom.4.html +//! [3]: https://www.unix.com/man-page/mojave/2/getentropy/ +//! [4]: https://www.unix.com/man-page/mojave/4/urandom/ +//! [5]: https://www.freebsd.org/cgi/man.cgi?query=getrandom&manpath=FreeBSD+12.0-stable +//! [6]: https://www.freebsd.org/cgi/man.cgi?query=random&sektion=4 +//! [7]: https://man.openbsd.org/getentropy.2 +//! [8]: https://man.netbsd.org/sysctl.7 +//! [9]: https://leaf.dragonflybsd.org/cgi/web-man?command=getrandom +//! [10]: https://leaf.dragonflybsd.org/cgi/web-man?command=random§ion=4 +//! [11]: https://docs.oracle.com/cd/E88353_01/html/E37841/getrandom-2.html +//! [12]: https://docs.oracle.com/cd/E86824_01/html/E54777/random-7d.html +//! [13]: https://github.com/emscripten-core/emscripten/pull/12240 +//! [14]: https://www.qnx.com/developers/docs/7.1/index.html#com.qnx.doc.neutrino.utilities/topic/r/random.html +//! [15]: https://www.ibm.com/docs/en/aix/7.3?topic=files-random-urandom-devices +//! [16]: https://man.netbsd.org/getrandom.2 +//! +//! [`BCryptGenRandom`]: https://docs.microsoft.com/en-us/windows/win32/api/bcrypt/nf-bcrypt-bcryptgenrandom +//! [`Crypto.getRandomValues`]: https://www.w3.org/TR/WebCryptoAPI/#Crypto-method-getRandomValues +//! [`RDRAND`]: https://software.intel.com/en-us/articles/intel-digital-random-number-generator-drng-software-implementation-guide +//! [`SecRandomCopyBytes`]: https://developer.apple.com/documentation/security/1399291-secrandomcopybytes?language=objc +//! [`cprng_draw`]: https://fuchsia.dev/fuchsia-src/zircon/syscalls/cprng_draw +//! [`crypto.randomFillSync`]: https://nodejs.org/api/crypto.html#cryptorandomfillsyncbuffer-offset-size +//! [`esp_fill_random`]: https://docs.espressif.com/projects/esp-idf/en/latest/esp32/api-reference/system/random.html#_CPPv415esp_fill_randomPv6size_t +//! [`random_get`]: https://github.com/WebAssembly/WASI/blob/main/phases/snapshot/docs.md#-random_getbuf-pointeru8-buf_len-size---errno +//! [WebAssembly support]: #webassembly-support +//! [`wasm-bindgen`]: https://github.com/rustwasm/wasm-bindgen +//! [`module`]: https://rustwasm.github.io/wasm-bindgen/reference/attributes/on-js-imports/module.html +//! [CommonJS modules]: https://nodejs.org/api/modules.html +//! [ES modules]: https://nodejs.org/api/esm.html +//! [`sys_read_entropy`]: https://hermitcore.github.io/libhermit-rs/hermit/fn.sys_read_entropy.html + +#![doc( + html_logo_url = "https://www.rust-lang.org/logos/rust-logo-128x128-blk.png", + html_favicon_url = "https://www.rust-lang.org/favicon.ico", + html_root_url = "https://docs.rs/getrandom/0.2.9" +)] +#![no_std] +#![warn(rust_2018_idioms, unused_lifetimes, missing_docs)] +#![cfg_attr(docsrs, feature(doc_cfg))] + +#[macro_use] +extern crate cfg_if; + +use crate::util::{slice_as_uninit_mut, slice_assume_init_mut}; +use core::mem::MaybeUninit; + +mod error; +mod util; +// To prevent a breaking change when targets are added, we always export the +// register_custom_getrandom macro, so old Custom RNG crates continue to build. +#[cfg(feature = "custom")] +mod custom; +#[cfg(feature = "std")] +mod error_impls; + +pub use crate::error::Error; + +// System-specific implementations. +// +// These should all provide getrandom_inner with the signature +// `fn getrandom_inner(dest: &mut [MaybeUninit<u8>]) -> Result<(), Error>`. +// The function MUST fully initialize `dest` when `Ok(())` is returned. +// The function MUST NOT ever write uninitialized bytes into `dest`, +// regardless of what value it returns. +cfg_if! { + if #[cfg(any(target_os = "haiku", target_os = "redox", target_os = "nto", target_os = "aix"))] { + mod util_libc; + #[path = "use_file.rs"] mod imp; + } else if #[cfg(any(target_os = "android", target_os = "linux"))] { + mod util_libc; + mod use_file; + #[path = "linux_android.rs"] mod imp; + } else if #[cfg(any(target_os = "illumos", target_os = "solaris"))] { + mod util_libc; + mod use_file; + #[path = "solaris_illumos.rs"] mod imp; + } else if #[cfg(any(target_os = "freebsd", target_os = "netbsd"))] { + mod util_libc; + #[path = "bsd_arandom.rs"] mod imp; + } else if #[cfg(target_os = "dragonfly")] { + mod util_libc; + mod use_file; + #[path = "dragonfly.rs"] mod imp; + } else if #[cfg(target_os = "fuchsia")] { + #[path = "fuchsia.rs"] mod imp; + } else if #[cfg(any(target_os = "ios", target_os = "watchos", target_os = "tvos"))] { + #[path = "apple-other.rs"] mod imp; + } else if #[cfg(target_os = "macos")] { + mod util_libc; + mod use_file; + #[path = "macos.rs"] mod imp; + } else if #[cfg(target_os = "openbsd")] { + mod util_libc; + #[path = "openbsd.rs"] mod imp; + } else if #[cfg(all(target_arch = "wasm32", target_os = "wasi"))] { + #[path = "wasi.rs"] mod imp; + } else if #[cfg(target_os = "hermit")] { + #[path = "hermit.rs"] mod imp; + } else if #[cfg(target_os = "vxworks")] { + mod util_libc; + #[path = "vxworks.rs"] mod imp; + } else if #[cfg(target_os = "solid_asp3")] { + #[path = "solid.rs"] mod imp; + } else if #[cfg(target_os = "espidf")] { + #[path = "espidf.rs"] mod imp; + } else if #[cfg(windows)] { + #[path = "windows.rs"] mod imp; + } else if #[cfg(all(target_os = "horizon", target_arch = "arm"))] { + // We check for target_arch = "arm" because the Nintendo Switch also + // uses Horizon OS (it is aarch64). + mod util_libc; + #[path = "3ds.rs"] mod imp; + } else if #[cfg(target_os = "emscripten")] { + mod util_libc; + #[path = "emscripten.rs"] mod imp; + } else if #[cfg(all(target_arch = "x86_64", target_env = "sgx"))] { + #[path = "rdrand.rs"] mod imp; + } else if #[cfg(all(feature = "rdrand", + any(target_arch = "x86_64", target_arch = "x86")))] { + #[path = "rdrand.rs"] mod imp; + } else if #[cfg(all(feature = "js", + any(target_arch = "wasm32", target_arch = "wasm64"), + target_os = "unknown"))] { + #[path = "js.rs"] mod imp; + } else if #[cfg(feature = "custom")] { + use custom as imp; + } else if #[cfg(all(any(target_arch = "wasm32", target_arch = "wasm64"), + target_os = "unknown"))] { + compile_error!("the wasm*-unknown-unknown targets are not supported by \ + default, you may need to enable the \"js\" feature. \ + For more information see: \ + https://docs.rs/getrandom/#webassembly-support"); + } else { + compile_error!("target is not supported, for more information see: \ + https://docs.rs/getrandom/#unsupported-targets"); + } +} + +/// Fill `dest` with random bytes from the system's preferred random number +/// source. +/// +/// This function returns an error on any failure, including partial reads. We +/// make no guarantees regarding the contents of `dest` on error. If `dest` is +/// empty, `getrandom` immediately returns success, making no calls to the +/// underlying operating system. +/// +/// Blocking is possible, at least during early boot; see module documentation. +/// +/// In general, `getrandom` will be fast enough for interactive usage, though +/// significantly slower than a user-space CSPRNG; for the latter consider +/// [`rand::thread_rng`](https://docs.rs/rand/*/rand/fn.thread_rng.html). +#[inline] +pub fn getrandom(dest: &mut [u8]) -> Result<(), Error> { + // SAFETY: The `&mut MaybeUninit<_>` reference doesn't escape, and + // `getrandom_uninit` guarantees it will never de-initialize any part of + // `dest`. + getrandom_uninit(unsafe { slice_as_uninit_mut(dest) })?; + Ok(()) +} + +/// Version of the `getrandom` function which fills `dest` with random bytes +/// returns a mutable reference to those bytes. +/// +/// On successful completion this function is guaranteed to return a slice +/// which points to the same memory as `dest` and has the same length. +/// In other words, it's safe to assume that `dest` is initialized after +/// this function has returned `Ok`. +/// +/// No part of `dest` will ever be de-initialized at any point, regardless +/// of what is returned. +/// +/// # Examples +/// +/// ```ignore +/// # // We ignore this test since `uninit_array` is unstable. +/// #![feature(maybe_uninit_uninit_array)] +/// # fn main() -> Result<(), getrandom::Error> { +/// let mut buf = core::mem::MaybeUninit::uninit_array::<1024>(); +/// let buf: &mut [u8] = getrandom::getrandom_uninit(&mut buf)?; +/// # Ok(()) } +/// ``` +#[inline] +pub fn getrandom_uninit(dest: &mut [MaybeUninit<u8>]) -> Result<&mut [u8], Error> { + if !dest.is_empty() { + imp::getrandom_inner(dest)?; + } + // SAFETY: `dest` has been fully initialized by `imp::getrandom_inner` + // since it returned `Ok`. + Ok(unsafe { slice_assume_init_mut(dest) }) +} diff --git a/third_party/rust/getrandom/src/linux_android.rs b/third_party/rust/getrandom/src/linux_android.rs new file mode 100644 index 0000000000..e81f1e1533 --- /dev/null +++ b/third_party/rust/getrandom/src/linux_android.rs @@ -0,0 +1,48 @@ +// Copyright 2018 Developers of the Rand project. +// +// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or +// https://www.apache.org/licenses/LICENSE-2.0> or the MIT license +// <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +//! Implementation for Linux / Android +use crate::{ + util::LazyBool, + util_libc::{last_os_error, sys_fill_exact}, + {use_file, Error}, +}; +use core::mem::MaybeUninit; + +pub fn getrandom_inner(dest: &mut [MaybeUninit<u8>]) -> Result<(), Error> { + // getrandom(2) was introduced in Linux 3.17 + static HAS_GETRANDOM: LazyBool = LazyBool::new(); + if HAS_GETRANDOM.unsync_init(is_getrandom_available) { + sys_fill_exact(dest, |buf| unsafe { + getrandom(buf.as_mut_ptr() as *mut libc::c_void, buf.len(), 0) + }) + } else { + use_file::getrandom_inner(dest) + } +} + +fn is_getrandom_available() -> bool { + let res = unsafe { getrandom(core::ptr::null_mut(), 0, libc::GRND_NONBLOCK) }; + if res < 0 { + match last_os_error().raw_os_error() { + Some(libc::ENOSYS) => false, // No kernel support + Some(libc::EPERM) => false, // Blocked by seccomp + _ => true, + } + } else { + true + } +} + +unsafe fn getrandom( + buf: *mut libc::c_void, + buflen: libc::size_t, + flags: libc::c_uint, +) -> libc::ssize_t { + libc::syscall(libc::SYS_getrandom, buf, buflen, flags) as libc::ssize_t +} diff --git a/third_party/rust/getrandom/src/macos.rs b/third_party/rust/getrandom/src/macos.rs new file mode 100644 index 0000000000..312f9b27f0 --- /dev/null +++ b/third_party/rust/getrandom/src/macos.rs @@ -0,0 +1,36 @@ +// Copyright 2019 Developers of the Rand project. +// +// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or +// https://www.apache.org/licenses/LICENSE-2.0> or the MIT license +// <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +//! Implementation for macOS +use crate::{ + use_file, + util_libc::{last_os_error, Weak}, + Error, +}; +use core::mem::{self, MaybeUninit}; + +type GetEntropyFn = unsafe extern "C" fn(*mut u8, libc::size_t) -> libc::c_int; + +pub fn getrandom_inner(dest: &mut [MaybeUninit<u8>]) -> Result<(), Error> { + // getentropy(2) was added in 10.12, Rust supports 10.7+ + static GETENTROPY: Weak = unsafe { Weak::new("getentropy\0") }; + if let Some(fptr) = GETENTROPY.ptr() { + let func: GetEntropyFn = unsafe { mem::transmute(fptr) }; + for chunk in dest.chunks_mut(256) { + let ret = unsafe { func(chunk.as_mut_ptr() as *mut u8, chunk.len()) }; + if ret != 0 { + return Err(last_os_error()); + } + } + Ok(()) + } else { + // We fallback to reading from /dev/random instead of SecRandomCopyBytes + // to avoid high startup costs and linking the Security framework. + use_file::getrandom_inner(dest) + } +} diff --git a/third_party/rust/getrandom/src/openbsd.rs b/third_party/rust/getrandom/src/openbsd.rs new file mode 100644 index 0000000000..7a76f61d5b --- /dev/null +++ b/third_party/rust/getrandom/src/openbsd.rs @@ -0,0 +1,22 @@ +// Copyright 2018 Developers of the Rand project. +// +// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or +// https://www.apache.org/licenses/LICENSE-2.0> or the MIT license +// <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +//! Implementation for OpenBSD +use crate::{util_libc::last_os_error, Error}; +use core::mem::MaybeUninit; + +pub fn getrandom_inner(dest: &mut [MaybeUninit<u8>]) -> Result<(), Error> { + // getentropy(2) was added in OpenBSD 5.6, so we can use it unconditionally. + for chunk in dest.chunks_mut(256) { + let ret = unsafe { libc::getentropy(chunk.as_mut_ptr() as *mut libc::c_void, chunk.len()) }; + if ret == -1 { + return Err(last_os_error()); + } + } + Ok(()) +} diff --git a/third_party/rust/getrandom/src/rdrand.rs b/third_party/rust/getrandom/src/rdrand.rs new file mode 100644 index 0000000000..69f6a5d13e --- /dev/null +++ b/third_party/rust/getrandom/src/rdrand.rs @@ -0,0 +1,130 @@ +// Copyright 2018 Developers of the Rand project. +// +// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or +// https://www.apache.org/licenses/LICENSE-2.0> or the MIT license +// <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. +use crate::{ + util::{slice_as_uninit, LazyBool}, + Error, +}; +use core::mem::{size_of, MaybeUninit}; + +cfg_if! { + if #[cfg(target_arch = "x86_64")] { + use core::arch::x86_64 as arch; + use arch::_rdrand64_step as rdrand_step; + } else if #[cfg(target_arch = "x86")] { + use core::arch::x86 as arch; + use arch::_rdrand32_step as rdrand_step; + } +} + +// Recommendation from "Intel® Digital Random Number Generator (DRNG) Software +// Implementation Guide" - Section 5.2.1 and "Intel® 64 and IA-32 Architectures +// Software Developer’s Manual" - Volume 1 - Section 7.3.17.1. +const RETRY_LIMIT: usize = 10; + +#[target_feature(enable = "rdrand")] +unsafe fn rdrand() -> Option<usize> { + for _ in 0..RETRY_LIMIT { + let mut val = 0; + if rdrand_step(&mut val) == 1 { + return Some(val as usize); + } + } + None +} + +// "rdrand" target feature requires "+rdrand" flag, see https://github.com/rust-lang/rust/issues/49653. +#[cfg(all(target_env = "sgx", not(target_feature = "rdrand")))] +compile_error!( + "SGX targets require 'rdrand' target feature. Enable by using -C target-feature=+rdrand." +); + +// Run a small self-test to make sure we aren't repeating values +// Adapted from Linux's test in arch/x86/kernel/cpu/rdrand.c +// Fails with probability < 2^(-90) on 32-bit systems +#[target_feature(enable = "rdrand")] +unsafe fn self_test() -> bool { + // On AMD, RDRAND returns 0xFF...FF on failure, count it as a collision. + let mut prev = !0; // TODO(MSRV 1.43): Move to usize::MAX + let mut fails = 0; + for _ in 0..8 { + match rdrand() { + Some(val) if val == prev => fails += 1, + Some(val) => prev = val, + None => return false, + }; + } + fails <= 2 +} + +fn is_rdrand_good() -> bool { + #[cfg(not(target_feature = "rdrand"))] + { + // SAFETY: All Rust x86 targets are new enough to have CPUID, and we + // check that leaf 1 is supported before using it. + let cpuid0 = unsafe { arch::__cpuid(0) }; + if cpuid0.eax < 1 { + return false; + } + let cpuid1 = unsafe { arch::__cpuid(1) }; + + let vendor_id = [ + cpuid0.ebx.to_le_bytes(), + cpuid0.edx.to_le_bytes(), + cpuid0.ecx.to_le_bytes(), + ]; + if vendor_id == [*b"Auth", *b"enti", *b"cAMD"] { + let mut family = (cpuid1.eax >> 8) & 0xF; + if family == 0xF { + family += (cpuid1.eax >> 20) & 0xFF; + } + // AMD CPUs families before 17h (Zen) sometimes fail to set CF when + // RDRAND fails after suspend. Don't use RDRAND on those families. + // See https://bugzilla.redhat.com/show_bug.cgi?id=1150286 + if family < 0x17 { + return false; + } + } + + const RDRAND_FLAG: u32 = 1 << 30; + if cpuid1.ecx & RDRAND_FLAG == 0 { + return false; + } + } + + // SAFETY: We have already checked that rdrand is available. + unsafe { self_test() } +} + +pub fn getrandom_inner(dest: &mut [MaybeUninit<u8>]) -> Result<(), Error> { + static RDRAND_GOOD: LazyBool = LazyBool::new(); + if !RDRAND_GOOD.unsync_init(is_rdrand_good) { + return Err(Error::NO_RDRAND); + } + // SAFETY: After this point, we know rdrand is supported. + unsafe { rdrand_exact(dest) }.ok_or(Error::FAILED_RDRAND) +} + +// TODO: make this function safe when we have feature(target_feature_11) +#[target_feature(enable = "rdrand")] +unsafe fn rdrand_exact(dest: &mut [MaybeUninit<u8>]) -> Option<()> { + // We use chunks_exact_mut instead of chunks_mut as it allows almost all + // calls to memcpy to be elided by the compiler. + let mut chunks = dest.chunks_exact_mut(size_of::<usize>()); + for chunk in chunks.by_ref() { + let src = rdrand()?.to_ne_bytes(); + chunk.copy_from_slice(slice_as_uninit(&src)); + } + + let tail = chunks.into_remainder(); + let n = tail.len(); + if n > 0 { + let src = rdrand()?.to_ne_bytes(); + tail.copy_from_slice(slice_as_uninit(&src[..n])); + } + Some(()) +} diff --git a/third_party/rust/getrandom/src/solaris_illumos.rs b/third_party/rust/getrandom/src/solaris_illumos.rs new file mode 100644 index 0000000000..501c610d77 --- /dev/null +++ b/third_party/rust/getrandom/src/solaris_illumos.rs @@ -0,0 +1,49 @@ +// Copyright 2018 Developers of the Rand project. +// +// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or +// https://www.apache.org/licenses/LICENSE-2.0> or the MIT license +// <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +//! Implementation for the Solaris family +//! +//! `/dev/random` uses the Hash_DRBG with SHA512 algorithm from NIST SP 800-90A. +//! `/dev/urandom` uses the FIPS 186-2 algorithm, which is considered less +//! secure. We choose to read from `/dev/random` (and use GRND_RANDOM). +//! +//! Solaris 11.3 and late-2018 illumos added the getrandom(2) libc function. +//! To make sure we can compile on both Solaris and its derivatives, as well as +//! function, we check for the existence of getrandom(2) in libc by calling +//! libc::dlsym. +use crate::{ + use_file, + util_libc::{sys_fill_exact, Weak}, + Error, +}; +use core::mem::{self, MaybeUninit}; + +static GETRANDOM: Weak = unsafe { Weak::new("getrandom\0") }; +type GetRandomFn = + unsafe extern "C" fn(*mut libc::c_void, libc::size_t, libc::c_uint) -> libc::ssize_t; + +pub fn getrandom_inner(dest: &mut [MaybeUninit<u8>]) -> Result<(), Error> { + if let Some(fptr) = GETRANDOM.ptr() { + let func: GetRandomFn = unsafe { mem::transmute(fptr) }; + // 256 bytes is the lowest common denominator across all the Solaris + // derived platforms for atomically obtaining random data. + for chunk in dest.chunks_mut(256) { + sys_fill_exact(chunk, |buf| unsafe { + // A cast is needed for the flags as libc uses the wrong type. + func( + buf.as_mut_ptr() as *mut libc::c_void, + buf.len(), + libc::GRND_RANDOM as libc::c_uint, + ) + })? + } + Ok(()) + } else { + use_file::getrandom_inner(dest) + } +} diff --git a/third_party/rust/getrandom/src/solid.rs b/third_party/rust/getrandom/src/solid.rs new file mode 100644 index 0000000000..aeccc4e2bd --- /dev/null +++ b/third_party/rust/getrandom/src/solid.rs @@ -0,0 +1,26 @@ +// Copyright 2021 Developers of the Rand project. +// +// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or +// https://www.apache.org/licenses/LICENSE-2.0> or the MIT license +// <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +//! Implementation for SOLID +use crate::Error; +use core::{mem::MaybeUninit, num::NonZeroU32}; + +extern "C" { + pub fn SOLID_RNG_SampleRandomBytes(buffer: *mut u8, length: usize) -> i32; +} + +pub fn getrandom_inner(dest: &mut [MaybeUninit<u8>]) -> Result<(), Error> { + let ret = unsafe { SOLID_RNG_SampleRandomBytes(dest.as_mut_ptr() as *mut u8, dest.len()) }; + if ret >= 0 { + Ok(()) + } else { + // ITRON error numbers are always negative, so we negate it so that it + // falls in the dedicated OS error range (1..INTERNAL_START). + Err(NonZeroU32::new((-ret) as u32).unwrap().into()) + } +} diff --git a/third_party/rust/getrandom/src/use_file.rs b/third_party/rust/getrandom/src/use_file.rs new file mode 100644 index 0000000000..a6ef0d2350 --- /dev/null +++ b/third_party/rust/getrandom/src/use_file.rs @@ -0,0 +1,138 @@ +// Copyright 2018 Developers of the Rand project. +// +// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or +// https://www.apache.org/licenses/LICENSE-2.0> or the MIT license +// <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +//! Implementations that just need to read from a file +use crate::{ + util::LazyUsize, + util_libc::{open_readonly, sys_fill_exact}, + Error, +}; +use core::{ + cell::UnsafeCell, + mem::MaybeUninit, + sync::atomic::{AtomicUsize, Ordering::Relaxed}, +}; + +// We prefer using /dev/urandom and only use /dev/random if the OS +// documentation indicates that /dev/urandom is insecure. +// On Solaris/Illumos, see src/solaris_illumos.rs +// On Dragonfly, Haiku, macOS, and QNX Neutrino the devices are identical. +#[cfg(any(target_os = "solaris", target_os = "illumos"))] +const FILE_PATH: &str = "/dev/random\0"; +#[cfg(any( + target_os = "aix", + target_os = "android", + target_os = "linux", + target_os = "redox", + target_os = "dragonfly", + target_os = "haiku", + target_os = "macos", + target_os = "nto", +))] +const FILE_PATH: &str = "/dev/urandom\0"; + +pub fn getrandom_inner(dest: &mut [MaybeUninit<u8>]) -> Result<(), Error> { + let fd = get_rng_fd()?; + sys_fill_exact(dest, |buf| unsafe { + libc::read(fd, buf.as_mut_ptr() as *mut libc::c_void, buf.len()) + }) +} + +// Returns the file descriptor for the device file used to retrieve random +// bytes. The file will be opened exactly once. All subsequent calls will +// return the same file descriptor. This file descriptor is never closed. +fn get_rng_fd() -> Result<libc::c_int, Error> { + static FD: AtomicUsize = AtomicUsize::new(LazyUsize::UNINIT); + fn get_fd() -> Option<libc::c_int> { + match FD.load(Relaxed) { + LazyUsize::UNINIT => None, + val => Some(val as libc::c_int), + } + } + + // Use double-checked locking to avoid acquiring the lock if possible. + if let Some(fd) = get_fd() { + return Ok(fd); + } + + // SAFETY: We use the mutex only in this method, and we always unlock it + // before returning, making sure we don't violate the pthread_mutex_t API. + static MUTEX: Mutex = Mutex::new(); + unsafe { MUTEX.lock() }; + let _guard = DropGuard(|| unsafe { MUTEX.unlock() }); + + if let Some(fd) = get_fd() { + return Ok(fd); + } + + // On Linux, /dev/urandom might return insecure values. + #[cfg(any(target_os = "android", target_os = "linux"))] + wait_until_rng_ready()?; + + let fd = unsafe { open_readonly(FILE_PATH)? }; + // The fd always fits in a usize without conflicting with UNINIT. + debug_assert!(fd >= 0 && (fd as usize) < LazyUsize::UNINIT); + FD.store(fd as usize, Relaxed); + + Ok(fd) +} + +// Succeeds once /dev/urandom is safe to read from +#[cfg(any(target_os = "android", target_os = "linux"))] +fn wait_until_rng_ready() -> Result<(), Error> { + // Poll /dev/random to make sure it is ok to read from /dev/urandom. + let fd = unsafe { open_readonly("/dev/random\0")? }; + let mut pfd = libc::pollfd { + fd, + events: libc::POLLIN, + revents: 0, + }; + let _guard = DropGuard(|| unsafe { + libc::close(fd); + }); + + loop { + // A negative timeout means an infinite timeout. + let res = unsafe { libc::poll(&mut pfd, 1, -1) }; + if res >= 0 { + debug_assert_eq!(res, 1); // We only used one fd, and cannot timeout. + return Ok(()); + } + let err = crate::util_libc::last_os_error(); + match err.raw_os_error() { + Some(libc::EINTR) | Some(libc::EAGAIN) => continue, + _ => return Err(err), + } + } +} + +struct Mutex(UnsafeCell<libc::pthread_mutex_t>); + +impl Mutex { + const fn new() -> Self { + Self(UnsafeCell::new(libc::PTHREAD_MUTEX_INITIALIZER)) + } + unsafe fn lock(&self) { + let r = libc::pthread_mutex_lock(self.0.get()); + debug_assert_eq!(r, 0); + } + unsafe fn unlock(&self) { + let r = libc::pthread_mutex_unlock(self.0.get()); + debug_assert_eq!(r, 0); + } +} + +unsafe impl Sync for Mutex {} + +struct DropGuard<F: FnMut()>(F); + +impl<F: FnMut()> Drop for DropGuard<F> { + fn drop(&mut self) { + self.0() + } +} diff --git a/third_party/rust/getrandom/src/util.rs b/third_party/rust/getrandom/src/util.rs new file mode 100644 index 0000000000..3162afad35 --- /dev/null +++ b/third_party/rust/getrandom/src/util.rs @@ -0,0 +1,101 @@ +// Copyright 2019 Developers of the Rand project. +// +// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or +// https://www.apache.org/licenses/LICENSE-2.0> or the MIT license +// <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. +#![allow(dead_code)] +use core::{ + mem::MaybeUninit, + ptr, + sync::atomic::{AtomicUsize, Ordering::Relaxed}, +}; + +// This structure represents a lazily initialized static usize value. Useful +// when it is preferable to just rerun initialization instead of locking. +// Both unsync_init and sync_init will invoke an init() function until it +// succeeds, then return the cached value for future calls. +// +// Both methods support init() "failing". If the init() method returns UNINIT, +// that value will be returned as normal, but will not be cached. +// +// Users should only depend on the _value_ returned by init() functions. +// Specifically, for the following init() function: +// fn init() -> usize { +// a(); +// let v = b(); +// c(); +// v +// } +// the effects of c() or writes to shared memory will not necessarily be +// observed and additional synchronization methods with be needed. +pub struct LazyUsize(AtomicUsize); + +impl LazyUsize { + pub const fn new() -> Self { + Self(AtomicUsize::new(Self::UNINIT)) + } + + // The initialization is not completed. + pub const UNINIT: usize = usize::max_value(); + + // Runs the init() function at least once, returning the value of some run + // of init(). Multiple callers can run their init() functions in parallel. + // init() should always return the same value, if it succeeds. + pub fn unsync_init(&self, init: impl FnOnce() -> usize) -> usize { + // Relaxed ordering is fine, as we only have a single atomic variable. + let mut val = self.0.load(Relaxed); + if val == Self::UNINIT { + val = init(); + self.0.store(val, Relaxed); + } + val + } +} + +// Identical to LazyUsize except with bool instead of usize. +pub struct LazyBool(LazyUsize); + +impl LazyBool { + pub const fn new() -> Self { + Self(LazyUsize::new()) + } + + pub fn unsync_init(&self, init: impl FnOnce() -> bool) -> bool { + self.0.unsync_init(|| init() as usize) != 0 + } +} + +/// Polyfill for `maybe_uninit_slice` feature's +/// `MaybeUninit::slice_assume_init_mut`. Every element of `slice` must have +/// been initialized. +#[inline(always)] +pub unsafe fn slice_assume_init_mut<T>(slice: &mut [MaybeUninit<T>]) -> &mut [T] { + // SAFETY: `MaybeUninit<T>` is guaranteed to be layout-compatible with `T`. + &mut *(slice as *mut [MaybeUninit<T>] as *mut [T]) +} + +#[inline] +pub fn uninit_slice_fill_zero(slice: &mut [MaybeUninit<u8>]) -> &mut [u8] { + unsafe { ptr::write_bytes(slice.as_mut_ptr(), 0, slice.len()) }; + unsafe { slice_assume_init_mut(slice) } +} + +#[inline(always)] +pub fn slice_as_uninit<T>(slice: &[T]) -> &[MaybeUninit<T>] { + // SAFETY: `MaybeUninit<T>` is guaranteed to be layout-compatible with `T`. + // There is no risk of writing a `MaybeUninit<T>` into the result since + // the result isn't mutable. + unsafe { &*(slice as *const [T] as *const [MaybeUninit<T>]) } +} + +/// View an mutable initialized array as potentially-uninitialized. +/// +/// This is unsafe because it allows assigning uninitialized values into +/// `slice`, which would be undefined behavior. +#[inline(always)] +pub unsafe fn slice_as_uninit_mut<T>(slice: &mut [T]) -> &mut [MaybeUninit<T>] { + // SAFETY: `MaybeUninit<T>` is guaranteed to be layout-compatible with `T`. + &mut *(slice as *mut [T] as *mut [MaybeUninit<T>]) +} diff --git a/third_party/rust/getrandom/src/util_libc.rs b/third_party/rust/getrandom/src/util_libc.rs new file mode 100644 index 0000000000..de1455c58e --- /dev/null +++ b/third_party/rust/getrandom/src/util_libc.rs @@ -0,0 +1,159 @@ +// Copyright 2019 Developers of the Rand project. +// +// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or +// https://www.apache.org/licenses/LICENSE-2.0> or the MIT license +// <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. +#![allow(dead_code)] +use crate::Error; +use core::{ + cmp::min, + mem::MaybeUninit, + num::NonZeroU32, + ptr::NonNull, + sync::atomic::{fence, AtomicPtr, Ordering}, +}; +use libc::c_void; + +cfg_if! { + if #[cfg(any(target_os = "netbsd", target_os = "openbsd", target_os = "android"))] { + use libc::__errno as errno_location; + } else if #[cfg(any(target_os = "linux", target_os = "emscripten", target_os = "redox"))] { + use libc::__errno_location as errno_location; + } else if #[cfg(any(target_os = "solaris", target_os = "illumos"))] { + use libc::___errno as errno_location; + } else if #[cfg(any(target_os = "macos", target_os = "freebsd"))] { + use libc::__error as errno_location; + } else if #[cfg(target_os = "haiku")] { + use libc::_errnop as errno_location; + } else if #[cfg(target_os = "nto")] { + use libc::__get_errno_ptr as errno_location; + } else if #[cfg(all(target_os = "horizon", target_arch = "arm"))] { + extern "C" { + // Not provided by libc: https://github.com/rust-lang/libc/issues/1995 + fn __errno() -> *mut libc::c_int; + } + use __errno as errno_location; + } else if #[cfg(target_os = "aix")] { + use libc::_Errno as errno_location; + } +} + +cfg_if! { + if #[cfg(target_os = "vxworks")] { + use libc::errnoGet as get_errno; + } else if #[cfg(target_os = "dragonfly")] { + // Until rust-lang/rust#29594 is stable, we cannot get the errno value + // on DragonFlyBSD. So we just return an out-of-range errno. + unsafe fn get_errno() -> libc::c_int { -1 } + } else { + unsafe fn get_errno() -> libc::c_int { *errno_location() } + } +} + +pub fn last_os_error() -> Error { + let errno = unsafe { get_errno() }; + if errno > 0 { + Error::from(NonZeroU32::new(errno as u32).unwrap()) + } else { + Error::ERRNO_NOT_POSITIVE + } +} + +// Fill a buffer by repeatedly invoking a system call. The `sys_fill` function: +// - should return -1 and set errno on failure +// - should return the number of bytes written on success +pub fn sys_fill_exact( + mut buf: &mut [MaybeUninit<u8>], + sys_fill: impl Fn(&mut [MaybeUninit<u8>]) -> libc::ssize_t, +) -> Result<(), Error> { + while !buf.is_empty() { + let res = sys_fill(buf); + if res < 0 { + let err = last_os_error(); + // We should try again if the call was interrupted. + if err.raw_os_error() != Some(libc::EINTR) { + return Err(err); + } + } else { + // We don't check for EOF (ret = 0) as the data we are reading + // should be an infinite stream of random bytes. + let len = min(res as usize, buf.len()); + buf = &mut buf[len..]; + } + } + Ok(()) +} + +// A "weak" binding to a C function that may or may not be present at runtime. +// Used for supporting newer OS features while still building on older systems. +// Based off of the DlsymWeak struct in libstd: +// https://github.com/rust-lang/rust/blob/1.61.0/library/std/src/sys/unix/weak.rs#L84 +// except that the caller must manually cast self.ptr() to a function pointer. +pub struct Weak { + name: &'static str, + addr: AtomicPtr<c_void>, +} + +impl Weak { + // A non-null pointer value which indicates we are uninitialized. This + // constant should ideally not be a valid address of a function pointer. + // However, if by chance libc::dlsym does return UNINIT, there will not + // be undefined behavior. libc::dlsym will just be called each time ptr() + // is called. This would be inefficient, but correct. + // TODO: Replace with core::ptr::invalid_mut(1) when that is stable. + const UNINIT: *mut c_void = 1 as *mut c_void; + + // Construct a binding to a C function with a given name. This function is + // unsafe because `name` _must_ be null terminated. + pub const unsafe fn new(name: &'static str) -> Self { + Self { + name, + addr: AtomicPtr::new(Self::UNINIT), + } + } + + // Return the address of a function if present at runtime. Otherwise, + // return None. Multiple callers can call ptr() concurrently. It will + // always return _some_ value returned by libc::dlsym. However, the + // dlsym function may be called multiple times. + pub fn ptr(&self) -> Option<NonNull<c_void>> { + // Despite having only a single atomic variable (self.addr), we still + // cannot always use Ordering::Relaxed, as we need to make sure a + // successful call to dlsym() is "ordered before" any data read through + // the returned pointer (which occurs when the function is called). + // Our implementation mirrors that of the one in libstd, meaning that + // the use of non-Relaxed operations is probably unnecessary. + match self.addr.load(Ordering::Relaxed) { + Self::UNINIT => { + let symbol = self.name.as_ptr() as *const _; + let addr = unsafe { libc::dlsym(libc::RTLD_DEFAULT, symbol) }; + // Synchronizes with the Acquire fence below + self.addr.store(addr, Ordering::Release); + NonNull::new(addr) + } + addr => { + let func = NonNull::new(addr)?; + fence(Ordering::Acquire); + Some(func) + } + } + } +} + +// SAFETY: path must be null terminated, FD must be manually closed. +pub unsafe fn open_readonly(path: &str) -> Result<libc::c_int, Error> { + debug_assert_eq!(path.as_bytes().last(), Some(&0)); + loop { + let fd = libc::open(path.as_ptr() as *const _, libc::O_RDONLY | libc::O_CLOEXEC); + if fd >= 0 { + return Ok(fd); + } + let err = last_os_error(); + // We should try again if open() was interrupted. + if err.raw_os_error() != Some(libc::EINTR) { + return Err(err); + } + } +} diff --git a/third_party/rust/getrandom/src/vxworks.rs b/third_party/rust/getrandom/src/vxworks.rs new file mode 100644 index 0000000000..9b2090fb0a --- /dev/null +++ b/third_party/rust/getrandom/src/vxworks.rs @@ -0,0 +1,37 @@ +// Copyright 2018 Developers of the Rand project. +// +// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or +// https://www.apache.org/licenses/LICENSE-2.0> or the MIT license +// <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +//! Implementation for VxWorks +use crate::{util_libc::last_os_error, Error}; +use core::{ + mem::MaybeUninit, + sync::atomic::{AtomicBool, Ordering::Relaxed}, +}; + +pub fn getrandom_inner(dest: &mut [MaybeUninit<u8>]) -> Result<(), Error> { + static RNG_INIT: AtomicBool = AtomicBool::new(false); + while !RNG_INIT.load(Relaxed) { + let ret = unsafe { libc::randSecure() }; + if ret < 0 { + return Err(Error::VXWORKS_RAND_SECURE); + } else if ret > 0 { + RNG_INIT.store(true, Relaxed); + break; + } + unsafe { libc::usleep(10) }; + } + + // Prevent overflow of i32 + for chunk in dest.chunks_mut(i32::max_value() as usize) { + let ret = unsafe { libc::randABytes(chunk.as_mut_ptr() as *mut u8, chunk.len() as i32) }; + if ret != 0 { + return Err(last_os_error()); + } + } + Ok(()) +} diff --git a/third_party/rust/getrandom/src/wasi.rs b/third_party/rust/getrandom/src/wasi.rs new file mode 100644 index 0000000000..9276ee74f8 --- /dev/null +++ b/third_party/rust/getrandom/src/wasi.rs @@ -0,0 +1,25 @@ +// Copyright 2018 Developers of the Rand project. +// +// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or +// https://www.apache.org/licenses/LICENSE-2.0> or the MIT license +// <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +//! Implementation for WASI +use crate::Error; +use core::{ + mem::MaybeUninit, + num::{NonZeroU16, NonZeroU32}, +}; +use wasi::random_get; + +pub fn getrandom_inner(dest: &mut [MaybeUninit<u8>]) -> Result<(), Error> { + unsafe { random_get(dest.as_mut_ptr() as *mut u8, dest.len()) }.map_err(|e| { + // The WASI errno will always be non-zero, but we check just in case. + match NonZeroU16::new(e.raw()) { + Some(r) => Error::from(NonZeroU32::from(r)), + None => Error::ERRNO_NOT_POSITIVE, + } + }) +} diff --git a/third_party/rust/getrandom/src/windows.rs b/third_party/rust/getrandom/src/windows.rs new file mode 100644 index 0000000000..92d70429e4 --- /dev/null +++ b/third_party/rust/getrandom/src/windows.rs @@ -0,0 +1,66 @@ +// Copyright 2018 Developers of the Rand project. +// +// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or +// https://www.apache.org/licenses/LICENSE-2.0> or the MIT license +// <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +use crate::Error; +use core::{ffi::c_void, mem::MaybeUninit, num::NonZeroU32, ptr}; + +const BCRYPT_USE_SYSTEM_PREFERRED_RNG: u32 = 0x00000002; + +#[link(name = "bcrypt")] +extern "system" { + fn BCryptGenRandom( + hAlgorithm: *mut c_void, + pBuffer: *mut u8, + cbBuffer: u32, + dwFlags: u32, + ) -> u32; +} + +// Forbidden when targetting UWP +#[cfg(not(target_vendor = "uwp"))] +#[link(name = "advapi32")] +extern "system" { + #[link_name = "SystemFunction036"] + fn RtlGenRandom(RandomBuffer: *mut c_void, RandomBufferLength: u32) -> u8; +} + +pub fn getrandom_inner(dest: &mut [MaybeUninit<u8>]) -> Result<(), Error> { + // Prevent overflow of u32 + for chunk in dest.chunks_mut(u32::max_value() as usize) { + // BCryptGenRandom was introduced in Windows Vista + let ret = unsafe { + BCryptGenRandom( + ptr::null_mut(), + chunk.as_mut_ptr() as *mut u8, + chunk.len() as u32, + BCRYPT_USE_SYSTEM_PREFERRED_RNG, + ) + }; + // NTSTATUS codes use the two highest bits for severity status. + if ret >> 30 == 0b11 { + // Failed. Try RtlGenRandom as a fallback. + #[cfg(not(target_vendor = "uwp"))] + { + let ret = + unsafe { RtlGenRandom(chunk.as_mut_ptr() as *mut c_void, chunk.len() as u32) }; + if ret != 0 { + continue; + } + } + // We zeroize the highest bit, so the error code will reside + // inside the range designated for OS codes. + let code = ret ^ (1 << 31); + // SAFETY: the second highest bit is always equal to one, + // so it's impossible to get zero. Unfortunately the type + // system does not have a way to express this yet. + let code = unsafe { NonZeroU32::new_unchecked(code) }; + return Err(Error::from(code)); + } + } + Ok(()) +} |