Snap for 6686656 from a11d0652920fdeefecef2705a9366b4eb1f386b0 to sdk-release
Change-Id: I3fc9814c3f29d69a6a077a28e66a4974c0014d98
diff --git a/.cargo_vcs_info.json b/.cargo_vcs_info.json
new file mode 100644
index 0000000..d17f1ee
--- /dev/null
+++ b/.cargo_vcs_info.json
@@ -0,0 +1,5 @@
+{
+ "git": {
+ "sha1": "33b859bae16ae0b1c782e48db2ed96eb2306a2fc"
+ }
+}
diff --git a/Android.bp b/Android.bp
new file mode 100644
index 0000000..0a49d28
--- /dev/null
+++ b/Android.bp
@@ -0,0 +1,17 @@
+// This file is generated by cargo2android.py --device --run --dependencies.
+
+rust_library {
+ name: "libgetrandom",
+ host_supported: true,
+ crate_name: "getrandom",
+ srcs: ["src/lib.rs"],
+ edition: "2018",
+ rustlibs: [
+ "libcfg_if",
+ "liblibc",
+ ],
+}
+
+// dependent_library ["feature_list"]
+// cfg-if-0.1.10
+// libc-0.2.72
diff --git a/CHANGELOG.md b/CHANGELOG.md
new file mode 100644
index 0000000..29b447c
--- /dev/null
+++ b/CHANGELOG.md
@@ -0,0 +1,168 @@
+# Changelog
+All notable changes to this project will be documented in this file.
+
+The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/)
+and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
+
+## [0.1.14] - 2020-01-07
+### Changed
+- Remove use of spin-locks in the `use_file` module. [#125]
+- Update `wasi` to v0.9. [#126]
+- Do not read errno value on DragonFlyBSD to fix compilation failure. [#129]
+
+[#125]: https://github.com/rust-random/getrandom/pull/125
+[#126]: https://github.com/rust-random/getrandom/pull/126
+[#129]: https://github.com/rust-random/getrandom/pull/129
+
+## [0.1.13] - 2019-08-25
+### Added
+- VxWorks targets support. [#86]
+
+### Changed
+- If zero-length slice is passed to the `getrandom` function, always return
+`Ok(())` immediately without doing any calls to the underlying operating
+system. [#104]
+- Use the `kern.arandom` sysctl on NetBSD. [#115]
+
+### Fixed
+- Bump `cfg-if` minimum version from 0.1.0 to 0.1.2. [#112]
+- Typos and bad doc links. [#117]
+
+[#86]: https://github.com/rust-random/getrandom/pull/86
+[#104]: https://github.com/rust-random/getrandom/pull/104
+[#112]: https://github.com/rust-random/getrandom/pull/112
+[#115]: https://github.com/rust-random/getrandom/pull/115
+[#117]: https://github.com/rust-random/getrandom/pull/117
+
+## [0.1.12] - 2019-08-18
+### Changed
+- Update wasi dependency from v0.5 to v0.7. [#100]
+
+[#100]: https://github.com/rust-random/getrandom/pull/100
+
+## [0.1.11] - 2019-08-25
+### Fixed
+- Implement `std`-dependent traits for selected targets even if `std`
+feature is disabled. (backward compatibility with v0.1.8) [#96]
+
+[#96]: https://github.com/rust-random/getrandom/pull/96
+
+## [0.1.10] - 2019-08-18 [YANKED]
+### Changed
+- Use the dummy implementation on `wasm32-unknown-unknown` even with the
+disabled `dummy` feature. [#90]
+
+### Fixed
+- Fix CSP error for `wasm-bindgen`. [#92]
+
+[#90]: https://github.com/rust-random/getrandom/pull/90
+[#92]: https://github.com/rust-random/getrandom/pull/92
+
+## [0.1.9] - 2019-08-14 [YANKED]
+### Changed
+- Remove `std` dependency for opening and reading files. [#58]
+- Use `wasi` isntead of `libc` on WASI target. [#64]
+- By default emit a compile-time error when built for an unsupported target.
+This behaviour can be disabled by using the `dummy` feature. [#71]
+
+### Added
+- Add support for UWP targets. [#69]
+- Add unstable `rustc-dep-of-std` feature. [#78]
+
+[#58]: https://github.com/rust-random/getrandom/pull/58
+[#64]: https://github.com/rust-random/getrandom/pull/64
+[#69]: https://github.com/rust-random/getrandom/pull/69
+[#71]: https://github.com/rust-random/getrandom/pull/71
+[#78]: https://github.com/rust-random/getrandom/pull/78
+
+## [0.1.8] - 2019-07-29
+### Changed
+- Explicitly specify types to arguments of 'libc::syscall'. [#74]
+
+[#74]: https://github.com/rust-random/getrandom/pull/74
+
+## [0.1.7] - 2019-07-29
+### Added
+- Support for hermit and l4re. [#61]
+- `Error::raw_os_error` method, `Error::INTERNAL_START` and
+`Error::CUSTOM_START` constants. Use `libc` for retrieving OS error descriptions. [#54]
+
+### Changed
+- Remove `lazy_static` dependency and use custom structures for lock-free
+initialization. [#51] [#52]
+- Try `getrandom()` first on FreeBSD. [#57]
+
+### Removed
+- Bitrig support. [#56]
+
+### Deprecated
+- `Error::UNKNOWN`, `Error::UNAVAILABLE`. [#54]
+
+[#51]: https://github.com/rust-random/getrandom/pull/51
+[#52]: https://github.com/rust-random/getrandom/pull/52
+[#54]: https://github.com/rust-random/getrandom/pull/54
+[#56]: https://github.com/rust-random/getrandom/pull/56
+[#57]: https://github.com/rust-random/getrandom/pull/57
+[#61]: https://github.com/rust-random/getrandom/pull/61
+
+## [0.1.6] - 2019-06-30
+### Changed
+- Minor change of RDRAND AMD bug handling. [#48]
+
+[#48]: https://github.com/rust-random/getrandom/pull/48
+
+## [0.1.5] - 2019-06-29
+### Fixed
+- Use shared `File` instead of shared file descriptor. [#44]
+- Workaround for RDRAND hardware bug present on some AMD CPUs. [#43]
+
+### Changed
+- Try `getentropy` and then fallback to `/dev/random` on macOS. [#38]
+
+[#38]: https://github.com/rust-random/getrandom/issues/38
+[#43]: https://github.com/rust-random/getrandom/pull/43
+[#44]: https://github.com/rust-random/getrandom/issues/44
+
+## [0.1.4] - 2019-06-28
+### Added
+- Add support for `x86_64-unknown-uefi` target by using RDRAND with CPUID
+feature detection. [#30]
+
+### Fixed
+- Fix long buffer issues on Windows and Linux. [#31] [#32]
+- Check `EPERM` in addition to `ENOSYS` on Linux. [#37]
+
+### Changed
+- Improve efficiency by sharing file descriptor across threads. [#13]
+- Remove `cloudabi`, `winapi`, and `fuchsia-cprng` dependencies. [#40]
+- Improve RDRAND implementation. [#24]
+- Don't block during syscall detection on Linux. [#26]
+- Increase consistency with libc implementation on FreeBSD. [#36]
+- Apply `rustfmt`. [#39]
+
+[#30]: https://github.com/rust-random/getrandom/pull/30
+[#13]: https://github.com/rust-random/getrandom/issues/13
+[#40]: https://github.com/rust-random/getrandom/pull/40
+[#26]: https://github.com/rust-random/getrandom/pull/26
+[#24]: https://github.com/rust-random/getrandom/pull/24
+[#39]: https://github.com/rust-random/getrandom/pull/39
+[#36]: https://github.com/rust-random/getrandom/pull/36
+[#31]: https://github.com/rust-random/getrandom/issues/31
+[#32]: https://github.com/rust-random/getrandom/issues/32
+[#37]: https://github.com/rust-random/getrandom/issues/37
+
+## [0.1.3] - 2019-05-15
+- Update for `wasm32-unknown-wasi` being renamed to `wasm32-wasi`, and for
+ WASI being categorized as an OS.
+
+## [0.1.2] - 2019-04-06
+- Add support for `wasm32-unknown-wasi` target.
+
+## [0.1.1] - 2019-04-05
+- Enable std functionality for CloudABI by default.
+
+## [0.1.0] - 2019-03-23
+Publish initial implementation.
+
+## [0.0.0] - 2019-01-19
+Publish an empty template library.
diff --git a/Cargo.toml b/Cargo.toml
new file mode 100644
index 0000000..1c1f718
--- /dev/null
+++ b/Cargo.toml
@@ -0,0 +1,63 @@
+# THIS FILE IS AUTOMATICALLY GENERATED BY CARGO
+#
+# When uploading crates to the registry Cargo will automatically
+# "normalize" Cargo.toml files for maximal compatibility
+# with all versions of Cargo and also rewrite `path` dependencies
+# to registry (e.g., crates.io) dependencies
+#
+# If you believe there's an error in this file please file an
+# issue against the rust-lang/cargo repository. If you're
+# editing this file be aware that the upstream Cargo.toml
+# will likely look very different (and much more reasonable)
+
+[package]
+edition = "2018"
+name = "getrandom"
+version = "0.1.14"
+authors = ["The Rand Project Developers"]
+exclude = ["utils/*", ".*", "appveyor.yml"]
+description = "A small cross-platform library for retrieving random data from system source"
+documentation = "https://docs.rs/getrandom"
+categories = ["os", "no-std"]
+license = "MIT OR Apache-2.0"
+repository = "https://github.com/rust-random/getrandom"
+[dependencies.cfg-if]
+version = "0.1.2"
+
+[dependencies.compiler_builtins]
+version = "0.1"
+optional = true
+
+[dependencies.core]
+version = "1.0"
+optional = true
+package = "rustc-std-workspace-core"
+
+[dependencies.log]
+version = "0.4"
+optional = true
+
+[features]
+dummy = []
+rustc-dep-of-std = ["compiler_builtins", "core"]
+std = []
+test-in-browser = ["wasm-bindgen"]
+[target."cfg(target_os = \"wasi\")".dependencies.wasi]
+version = "0.9"
+[target."cfg(unix)".dependencies.libc]
+version = "0.2.64"
+default-features = false
+[target.wasm32-unknown-unknown.dependencies.stdweb]
+version = "0.4.18"
+optional = true
+
+[target.wasm32-unknown-unknown.dependencies.wasm-bindgen]
+version = "0.2.29"
+optional = true
+[target.wasm32-unknown-unknown.dev-dependencies.wasm-bindgen-test]
+version = "0.2"
+[badges.appveyor]
+repository = "rust-random/getrandom"
+
+[badges.travis-ci]
+repository = "rust-random/getrandom"
diff --git a/Cargo.toml.orig b/Cargo.toml.orig
new file mode 100644
index 0000000..d10183f
--- /dev/null
+++ b/Cargo.toml.orig
@@ -0,0 +1,45 @@
+[package]
+name = "getrandom"
+version = "0.1.14"
+edition = "2018"
+authors = ["The Rand Project Developers"]
+license = "MIT OR Apache-2.0"
+description = "A small cross-platform library for retrieving random data from system source"
+documentation = "https://docs.rs/getrandom"
+repository = "https://github.com/rust-random/getrandom"
+categories = ["os", "no-std"]
+exclude = ["utils/*", ".*", "appveyor.yml"]
+
+[badges]
+travis-ci = { repository = "rust-random/getrandom" }
+appveyor = { repository = "rust-random/getrandom" }
+
+[dependencies]
+log = { version = "0.4", optional = true }
+cfg-if = "0.1.2"
+
+# When built as part of libstd
+compiler_builtins = { version = "0.1", optional = true }
+core = { version = "1.0", optional = true, package = "rustc-std-workspace-core" }
+
+[target.'cfg(unix)'.dependencies]
+libc = { version = "0.2.64", default-features = false }
+
+[target.'cfg(target_os = "wasi")'.dependencies]
+wasi = "0.9"
+
+[target.wasm32-unknown-unknown.dependencies]
+wasm-bindgen = { version = "0.2.29", optional = true }
+stdweb = { version = "0.4.18", optional = true }
+
+[target.wasm32-unknown-unknown.dev-dependencies]
+wasm-bindgen-test = "0.2"
+
+[features]
+std = []
+# Enables dummy implementation for unsupported targets
+dummy = []
+# Unstable feature to support being a libstd dependency
+rustc-dep-of-std = ["compiler_builtins", "core"]
+# Unstable feature for testing
+test-in-browser = ["wasm-bindgen"]
diff --git a/LICENSE b/LICENSE
new file mode 120000
index 0000000..6b579aa
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1 @@
+LICENSE-APACHE
\ No newline at end of file
diff --git a/LICENSE-APACHE b/LICENSE-APACHE
new file mode 100644
index 0000000..17d7468
--- /dev/null
+++ b/LICENSE-APACHE
@@ -0,0 +1,201 @@
+ Apache License
+ Version 2.0, January 2004
+ https://www.apache.org/licenses/
+
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+
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diff --git a/LICENSE-MIT b/LICENSE-MIT
new file mode 100644
index 0000000..d93b5ba
--- /dev/null
+++ b/LICENSE-MIT
@@ -0,0 +1,26 @@
+Copyright 2018 Developers of the Rand project
+Copyright (c) 2014 The Rust Project Developers
+
+Permission is hereby granted, free of charge, to any
+person obtaining a copy of this software and associated
+documentation files (the "Software"), to deal in the
+Software without restriction, including without
+limitation the rights to use, copy, modify, merge,
+publish, distribute, sublicense, and/or sell copies of
+the Software, and to permit persons to whom the Software
+is furnished to do so, subject to the following
+conditions:
+
+The above copyright notice and this permission notice
+shall be included in all copies or substantial portions
+of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF
+ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
+TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
+PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT
+SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR
+IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+DEALINGS IN THE SOFTWARE.
diff --git a/METADATA b/METADATA
new file mode 100644
index 0000000..fe630e7
--- /dev/null
+++ b/METADATA
@@ -0,0 +1,18 @@
+name: "getrandom"
+description:
+ "A small cross-platform library for retrieving random data from system "
+ "source"
+
+third_party {
+ url {
+ type: HOMEPAGE
+ value: "https://crates.io/crates/getrandom"
+ }
+ url {
+ type: GIT
+ value: "https://github.com/rust-random/getrandom"
+ }
+ version: "0.1.14"
+ last_upgrade_date { year: 2020 month: 6 day: 18 }
+ license_type: NOTICE
+}
diff --git a/MODULE_LICENSE_APACHE2 b/MODULE_LICENSE_APACHE2
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/MODULE_LICENSE_APACHE2
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..01bbfb5
--- /dev/null
+++ b/README.md
@@ -0,0 +1,78 @@
+# getrandom
+
+[](https://travis-ci.org/rust-random/getrandom)
+[](https://ci.appveyor.com/project/rust-random/getrandom)
+[](https://crates.io/crates/getrandom)
+[](https://docs.rs/getrandom)
+[](https://deps.rs/repo/github/rust-random/getrandom)
+
+
+A Rust library for retrieving random data from (operating) system source. It is
+assumed that system always provides high-quality cryptographically secure random
+data, ideally backed by hardware entropy sources. This crate derives its name
+from Linux's `getrandom` function, but is cross platform, roughly supporting
+the same set of platforms as Rust's `std` lib.
+
+This is a low-level API. Most users should prefer using high-level random-number
+library like [`rand`].
+
+[`rand`]: https://crates.io/crates/rand
+
+## Usage
+
+Add this to your `Cargo.toml`:
+
+```toml
+[dependencies]
+getrandom = "0.1"
+```
+
+Then invoke the `getrandom` function:
+
+```rust
+fn get_random_buf() -> Result<[u8; 32], getrandom::Error> {
+ let mut buf = [0u8; 32];
+ getrandom::getrandom(&mut buf)?;
+ Ok(buf)
+}
+```
+
+## Features
+
+This library is `no_std` for every supported target. However, getting randomness
+usually requires calling some external system API. This means most platforms
+will require linking against system libraries (i.e. `libc` for Unix,
+`Advapi32.dll` for Windows, Security framework on iOS, etc...).
+
+The `log` library is supported as an optional dependency. If enabled, error
+reporting will be improved on some platforms.
+
+For the `wasm32-unknown-unknown` target, one of the following features should be
+enabled:
+
+- [`wasm-bindgen`](https://crates.io/crates/wasm_bindgen)
+- [`stdweb`](https://crates.io/crates/stdweb)
+
+By default, compiling `getrandom` for an unsupported target will result in
+a compilation error. If you want to build an application which uses `getrandom`
+for such target, you can either:
+- Use [`[replace]`][replace] or [`[patch]`][patch] section in your `Cargo.toml`
+to switch to a custom implementation with a support of your target.
+- Enable the `dummy` feature to have getrandom use an implementation that always
+fails at run-time on unsupported targets.
+
+[replace]: https://doc.rust-lang.org/cargo/reference/manifest.html#the-replace-section
+[patch]: https://doc.rust-lang.org/cargo/reference/manifest.html#the-patch-section
+
+## Minimum Supported Rust Version
+
+This crate requires Rust 1.32.0 or later.
+
+# License
+
+The `getrandom` library is distributed under either of
+
+ * [Apache License, Version 2.0](LICENSE-APACHE)
+ * [MIT license](LICENSE-MIT)
+
+at your option.
diff --git a/benches/mod.rs b/benches/mod.rs
new file mode 100644
index 0000000..07953f1
--- /dev/null
+++ b/benches/mod.rs
@@ -0,0 +1,23 @@
+#![feature(test)]
+extern crate getrandom;
+extern crate test;
+
+#[bench]
+fn bench_64(b: &mut test::Bencher) {
+ let mut buf = [0u8; 64];
+ b.iter(|| {
+ getrandom::getrandom(&mut buf[..]).unwrap();
+ test::black_box(&buf);
+ });
+ b.bytes = buf.len() as u64;
+}
+
+#[bench]
+fn bench_65536(b: &mut test::Bencher) {
+ let mut buf = [0u8; 65536];
+ b.iter(|| {
+ getrandom::getrandom(&mut buf[..]).unwrap();
+ test::black_box(&buf);
+ });
+ b.bytes = buf.len() as u64;
+}
diff --git a/build.rs b/build.rs
new file mode 100644
index 0000000..1beb4ed
--- /dev/null
+++ b/build.rs
@@ -0,0 +1,19 @@
+#![deny(warnings)]
+
+use std::env;
+
+fn main() {
+ let target = env::var("TARGET").expect("TARGET was not set");
+ if target.contains("-uwp-windows-") {
+ // for BCryptGenRandom
+ println!("cargo:rustc-link-lib=bcrypt");
+ // to work around unavailability of `target_vendor` on Rust 1.33
+ println!("cargo:rustc-cfg=getrandom_uwp");
+ } else if target.contains("windows") {
+ // for RtlGenRandom (aka SystemFunction036)
+ println!("cargo:rustc-link-lib=advapi32");
+ } else if target.contains("apple-ios") {
+ // for SecRandomCopyBytes and kSecRandomDefault
+ println!("cargo:rustc-link-lib=framework=Security");
+ }
+}
diff --git a/src/bsd_arandom.rs b/src/bsd_arandom.rs
new file mode 100644
index 0000000..eb564ff
--- /dev/null
+++ b/src/bsd_arandom.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 FreeBSD and NetBSD
+use crate::util_libc::sys_fill_exact;
+use crate::Error;
+use core::ptr;
+
+fn kern_arnd(buf: &mut [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 {
+ error!("sysctl kern.arandom: syscall failed");
+ -1
+ } else {
+ len as libc::ssize_t
+ }
+}
+
+pub fn getrandom_inner(dest: &mut [u8]) -> Result<(), Error> {
+ #[cfg(target_os = "freebsd")]
+ {
+ use crate::util_libc::Weak;
+ 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;
+
+ 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(), buf.len(), 0) });
+ }
+ }
+ sys_fill_exact(dest, kern_arnd)
+}
diff --git a/src/cloudabi.rs b/src/cloudabi.rs
new file mode 100644
index 0000000..d3d0928
--- /dev/null
+++ b/src/cloudabi.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 CloudABI
+use crate::Error;
+use core::num::NonZeroU32;
+
+extern "C" {
+ fn cloudabi_sys_random_get(buf: *mut u8, buf_len: usize) -> u16;
+}
+
+pub fn getrandom_inner(dest: &mut [u8]) -> Result<(), Error> {
+ let errno = unsafe { cloudabi_sys_random_get(dest.as_mut_ptr(), dest.len()) };
+ if let Some(code) = NonZeroU32::new(errno as u32) {
+ error!("cloudabi_sys_random_get: failed with {}", errno);
+ Err(Error::from(code))
+ } else {
+ Ok(()) // Zero means success for CloudABI
+ }
+}
diff --git a/src/dummy.rs b/src/dummy.rs
new file mode 100644
index 0000000..0c24ba0
--- /dev/null
+++ b/src/dummy.rs
@@ -0,0 +1,14 @@
+// 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.
+
+//! A dummy implementation for unsupported targets which always fails
+use crate::{error::UNSUPPORTED, Error};
+
+pub fn getrandom_inner(_: &mut [u8]) -> Result<(), Error> {
+ Err(UNSUPPORTED)
+}
diff --git a/src/error.rs b/src/error.rs
new file mode 100644
index 0000000..31ae24d
--- /dev/null
+++ b/src/error.rs
@@ -0,0 +1,177 @@
+// 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;
+use core::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`].
+#[derive(Copy, Clone, Eq, PartialEq)]
+pub struct Error(NonZeroU32);
+
+impl Error {
+ #[deprecated(since = "0.1.7")]
+ /// Unknown error.
+ pub const UNKNOWN: Error = UNSUPPORTED;
+ #[deprecated(since = "0.1.7")]
+ /// System entropy source is unavailable.
+ pub const UNAVAILABLE: Error = UNSUPPORTED;
+
+ /// 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()`, except
+ /// that it works in `no_std` contexts. If this method returns `None`, the
+ /// error value can still be formatted via the `Display` implementation.
+ #[inline]
+ pub fn raw_os_error(self) -> Option<i32> {
+ if self.0.get() < Self::INTERNAL_START {
+ 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 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 if #[cfg(target_os = "wasi")] {
+ fn os_err(errno: i32, _buf: &mut [u8]) -> Option<wasi::Error> {
+ wasi::Error::from_raw_error(errno as _)
+ }
+ } 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)
+ }
+}
+
+// TODO: Convert to a function when min_version >= 1.33
+macro_rules! internal_error {
+ ($n:expr) => {
+ Error(unsafe { NonZeroU32::new_unchecked(Error::INTERNAL_START + $n as u16 as u32) })
+ };
+}
+
+/// Internal Error constants
+pub(crate) const UNSUPPORTED: Error = internal_error!(0);
+pub(crate) const ERRNO_NOT_POSITIVE: Error = internal_error!(1);
+pub(crate) const UNKNOWN_IO_ERROR: Error = internal_error!(2);
+pub(crate) const SEC_RANDOM_FAILED: Error = internal_error!(3);
+pub(crate) const RTL_GEN_RANDOM_FAILED: Error = internal_error!(4);
+pub(crate) const FAILED_RDRAND: Error = internal_error!(5);
+pub(crate) const NO_RDRAND: Error = internal_error!(6);
+pub(crate) const BINDGEN_CRYPTO_UNDEF: Error = internal_error!(7);
+pub(crate) const BINDGEN_GRV_UNDEF: Error = internal_error!(8);
+pub(crate) const STDWEB_NO_RNG: Error = internal_error!(9);
+pub(crate) const STDWEB_RNG_FAILED: Error = internal_error!(10);
+pub(crate) const RAND_SECURE_FATAL: Error = internal_error!(11);
+
+fn internal_desc(error: Error) -> Option<&'static str> {
+ match error {
+ UNSUPPORTED => Some("getrandom: this target is not supported"),
+ ERRNO_NOT_POSITIVE => Some("errno: did not return a positive value"),
+ UNKNOWN_IO_ERROR => Some("Unknown std::io::Error"),
+ SEC_RANDOM_FAILED => Some("SecRandomCopyBytes: call failed"),
+ RTL_GEN_RANDOM_FAILED => Some("RtlGenRandom: call failed"),
+ FAILED_RDRAND => Some("RDRAND: failed multiple times: CPU issue likely"),
+ NO_RDRAND => Some("RDRAND: instruction not supported"),
+ BINDGEN_CRYPTO_UNDEF => Some("wasm-bindgen: self.crypto is undefined"),
+ BINDGEN_GRV_UNDEF => Some("wasm-bindgen: crypto.getRandomValues is undefined"),
+ STDWEB_NO_RNG => Some("stdweb: no randomness source available"),
+ STDWEB_RNG_FAILED => Some("stdweb: failed to get randomness"),
+ RAND_SECURE_FATAL => Some("randSecure: random number generator module is not initialized"),
+ _ => 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/src/error_impls.rs b/src/error_impls.rs
new file mode 100644
index 0000000..007472e
--- /dev/null
+++ b/src/error_impls.rs
@@ -0,0 +1,35 @@
+// 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.
+extern crate std;
+
+use crate::{error::UNKNOWN_IO_ERROR, Error};
+use core::convert::From;
+use core::num::NonZeroU32;
+use std::io;
+
+impl From<io::Error> for Error {
+ fn from(err: io::Error) -> Self {
+ if let Some(errno) = err.raw_os_error() {
+ if let Some(code) = NonZeroU32::new(errno as u32) {
+ return Error::from(code);
+ }
+ }
+ UNKNOWN_IO_ERROR
+ }
+}
+
+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/src/fuchsia.rs b/src/fuchsia.rs
new file mode 100644
index 0000000..572ff53
--- /dev/null
+++ b/src/fuchsia.rs
@@ -0,0 +1,20 @@
+// 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;
+
+#[link(name = "zircon")]
+extern "C" {
+ fn zx_cprng_draw(buffer: *mut u8, length: usize);
+}
+
+pub fn getrandom_inner(dest: &mut [u8]) -> Result<(), Error> {
+ unsafe { zx_cprng_draw(dest.as_mut_ptr(), dest.len()) }
+ Ok(())
+}
diff --git a/src/ios.rs b/src/ios.rs
new file mode 100644
index 0000000..30c008c
--- /dev/null
+++ b/src/ios.rs
@@ -0,0 +1,31 @@
+// 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::SEC_RANDOM_FAILED, Error};
+
+// TODO: Make extern once extern_types feature is stabilized. See:
+// https://github.com/rust-lang/rust/issues/43467
+#[repr(C)]
+struct SecRandom([u8; 0]);
+
+#[link(name = "Security", kind = "framework")]
+extern "C" {
+ static kSecRandomDefault: *const SecRandom;
+
+ fn SecRandomCopyBytes(rnd: *const SecRandom, count: usize, bytes: *mut u8) -> i32;
+}
+
+pub fn getrandom_inner(dest: &mut [u8]) -> Result<(), Error> {
+ let ret = unsafe { SecRandomCopyBytes(kSecRandomDefault, dest.len(), dest.as_mut_ptr()) };
+ if ret == -1 {
+ Err(SEC_RANDOM_FAILED)
+ } else {
+ Ok(())
+ }
+}
diff --git a/src/lib.rs b/src/lib.rs
new file mode 100644
index 0000000..c305406
--- /dev/null
+++ b/src/lib.rs
@@ -0,0 +1,282 @@
+// 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 random number generator of the operating system.
+//!
+//! # Platform sources
+//!
+//! | OS | interface
+//! |------------------|---------------------------------------------------------
+//! | Linux, Android | [`getrandom`][1] system call if available, otherwise [`/dev/urandom`][2] after successfully polling `/dev/random`
+//! | Windows | [`RtlGenRandom`][3]
+//! | macOS | [`getentropy()`][19] if available, otherwise [`/dev/random`][20] (identical to `/dev/urandom`)
+//! | iOS | [`SecRandomCopyBytes`][4]
+//! | FreeBSD | [`getrandom()`][21] if available, otherwise [`kern.arandom`][5]
+//! | OpenBSD | [`getentropy`][6]
+//! | NetBSD | [`kern.arandom`][7]
+//! | Dragonfly BSD | [`/dev/random`][8]
+//! | Solaris, illumos | [`getrandom`][9] system call if available, otherwise [`/dev/random`][10]
+//! | Fuchsia OS | [`cprng_draw`][11]
+//! | Redox | [`rand:`][12]
+//! | CloudABI | [`cloudabi_sys_random_get`][13]
+//! | Haiku | `/dev/random` (identical to `/dev/urandom`)
+//! | L4RE, SGX, UEFI | [RDRAND][18]
+//! | Hermit | [RDRAND][18] as [`sys_rand`][22] is currently broken.
+//! | VxWorks | `randABytes` after checking entropy pool initialization with `randSecure`
+//! | Web browsers | [`Crypto.getRandomValues`][14] (see [Support for WebAssembly and asm.js][16])
+//! | Node.js | [`crypto.randomBytes`][15] (see [Support for WebAssembly and asm.js][16])
+//! | WASI | [`__wasi_random_get`][17]
+//!
+//! Getrandom doesn't have a blanket implementation for all Unix-like operating
+//! systems that reads from `/dev/urandom`. This ensures all supported operating
+//! systems are using the recommended interface and respect maximum buffer
+//! sizes.
+//!
+//! ## Unsupported targets
+//!
+//! By default, compiling `getrandom` for an unsupported target will result in
+//! a compilation error. If you want to build an application which uses `getrandom`
+//! for such target, you can either:
+//! - Use [`[replace]`][replace] or [`[patch]`][patch] section in your `Cargo.toml`
+//! to switch to a custom implementation with a support of your target.
+//! - Enable the `dummy` feature to have getrandom use an implementation that always
+//! fails at run-time on unsupported targets.
+//!
+//! [replace]: https://doc.rust-lang.org/cargo/reference/manifest.html#the-replace-section
+//! [patch]: https://doc.rust-lang.org/cargo/reference/manifest.html#the-patch-section
+//!
+//! ## Support for WebAssembly and asm.js
+//!
+//! Getrandom supports all of Rust's current `wasm32` targets, and it works with
+//! both Node.js and web browsers. The three Emscripten targets
+//! `asmjs-unknown-emscripten`, `wasm32-unknown-emscripten`, and
+//! `wasm32-experimental-emscripten` use Emscripten's `/dev/random` emulation.
+//! The WASI target `wasm32-wasi` uses the [`__wasi_random_get`][17] function
+//! defined by the WASI standard.
+//!
+//! Getrandom also supports `wasm32-unknown-unknown` by directly calling
+//! JavaScript methods. Rust currently has two ways to do this: [bindgen] and
+//! [stdweb]. Getrandom supports using either one by enabling the
+//! `wasm-bindgen` or `stdweb` crate features. Note that if both features are
+//! enabled, `wasm-bindgen` will be used. If neither feature is enabled, calls
+//! to `getrandom` will always fail at runtime.
+//!
+//! [bindgen]: https://github.com/rust-lang/rust-bindgen
+//! [stdweb]: https://github.com/koute/stdweb
+//!
+//! ## Early boot
+//!
+//! It is possible that early in the boot process the OS hasn't had enough time
+//! yet to collect entropy to securely seed its RNG, especially on virtual
+//! machines.
+//!
+//! Some operating systems always block the thread until the RNG is securely
+//! seeded. This can take anywhere from a few seconds to more than a minute.
+//! Others make a best effort to use a seed from before the shutdown and don't
+//! document much.
+//!
+//! 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) and on NetBSD
+//! reading from `/dev/urandom` never blocks, even when the OS hasn't collected
+//! enough entropy yet. To avoid returning low-entropy bytes, we first read from
+//! `/dev/random` and only switch to `/dev/urandom` once this has succeeded.
+//!
+//! # Error handling
+//!
+//! We always choose failure over returning 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.
+//!
+//! On unsupported platforms, `getrandom` always fails. See the [`Error`] type
+//! for more information on what data is returned on failure.
+//!
+//! [1]: http://man7.org/linux/man-pages/man2/getrandom.2.html
+//! [2]: http://man7.org/linux/man-pages/man4/urandom.4.html
+//! [3]: https://docs.microsoft.com/en-us/windows/desktop/api/ntsecapi/nf-ntsecapi-rtlgenrandom
+//! [4]: https://developer.apple.com/documentation/security/1399291-secrandomcopybytes?language=objc
+//! [5]: https://www.freebsd.org/cgi/man.cgi?query=random&sektion=4
+//! [6]: https://man.openbsd.org/getentropy.2
+//! [7]: https://netbsd.gw.com/cgi-bin/man-cgi?sysctl+7+NetBSD-8.0
+//! [8]: https://leaf.dragonflybsd.org/cgi/web-man?command=random§ion=4
+//! [9]: https://docs.oracle.com/cd/E88353_01/html/E37841/getrandom-2.html
+//! [10]: https://docs.oracle.com/cd/E86824_01/html/E54777/random-7d.html
+//! [11]: https://fuchsia.dev/fuchsia-src/zircon/syscalls/cprng_draw
+//! [12]: https://github.com/redox-os/randd/blob/master/src/main.rs
+//! [13]: https://github.com/nuxinl/cloudabi#random_get
+//! [14]: https://www.w3.org/TR/WebCryptoAPI/#Crypto-method-getRandomValues
+//! [15]: https://nodejs.org/api/crypto.html#crypto_crypto_randombytes_size_callback
+//! [16]: #support-for-webassembly-and-asmjs
+//! [17]: https://github.com/WebAssembly/WASI/blob/master/design/WASI-core.md#__wasi_random_get
+//! [18]: https://software.intel.com/en-us/articles/intel-digital-random-number-generator-drng-software-implementation-guide
+//! [19]: https://www.unix.com/man-page/mojave/2/getentropy/
+//! [20]: https://www.unix.com/man-page/mojave/4/random/
+//! [21]: https://www.freebsd.org/cgi/man.cgi?query=getrandom&manpath=FreeBSD+12.0-stable
+//! [22]: https://github.com/hermitcore/libhermit-rs/blob/09c38b0371cee6f56a541400ba453e319e43db53/src/syscalls/random.rs#L21
+
+#![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://rust-random.github.io/rand/"
+)]
+#![no_std]
+#![cfg_attr(feature = "stdweb", recursion_limit = "128")]
+#![warn(rust_2018_idioms, unused_lifetimes, missing_docs)]
+
+#[macro_use]
+extern crate cfg_if;
+
+cfg_if! {
+ if #[cfg(feature = "log")] {
+ #[allow(unused)]
+ #[macro_use]
+ extern crate log;
+ } else {
+ #[allow(unused)]
+ macro_rules! error {
+ ($($x:tt)*) => {};
+ }
+ #[allow(unused)]
+ macro_rules! warn {
+ ($($x:tt)*) => {};
+ }
+ #[allow(unused)]
+ macro_rules! info {
+ ($($x:tt)*) => {};
+ }
+ }
+}
+
+mod error;
+pub use crate::error::Error;
+
+#[allow(dead_code)]
+mod util;
+
+#[cfg(target_os = "vxworks")]
+#[allow(dead_code)]
+mod util_libc;
+
+cfg_if! {
+ // Unlike the other Unix, Fuchsia and iOS don't use the libc to make any calls.
+ if #[cfg(any(target_os = "android", target_os = "dragonfly", target_os = "emscripten",
+ target_os = "freebsd", target_os = "haiku", target_os = "illumos",
+ target_os = "linux", target_os = "macos", target_os = "netbsd",
+ target_os = "openbsd", target_os = "redox", target_os = "solaris"))] {
+ #[allow(dead_code)]
+ mod util_libc;
+ // Keep std-only trait definitions for backwards compatibility
+ mod error_impls;
+ } else if #[cfg(feature = "std")] {
+ mod error_impls;
+ }
+}
+
+// These targets read from a file as a fallback method.
+#[cfg(any(
+ target_os = "android",
+ target_os = "linux",
+ target_os = "macos",
+ target_os = "solaris",
+ target_os = "illumos",
+))]
+mod use_file;
+
+// System-specific implementations.
+//
+// These should all provide getrandom_inner with the same signature as getrandom.
+cfg_if! {
+ if #[cfg(target_os = "android")] {
+ #[path = "linux_android.rs"] mod imp;
+ } else if #[cfg(target_os = "cloudabi")] {
+ #[path = "cloudabi.rs"] mod imp;
+ } else if #[cfg(target_os = "dragonfly")] {
+ #[path = "use_file.rs"] mod imp;
+ } else if #[cfg(target_os = "emscripten")] {
+ #[path = "use_file.rs"] mod imp;
+ } else if #[cfg(target_os = "freebsd")] {
+ #[path = "bsd_arandom.rs"] mod imp;
+ } else if #[cfg(target_os = "fuchsia")] {
+ #[path = "fuchsia.rs"] mod imp;
+ } else if #[cfg(target_os = "haiku")] {
+ #[path = "use_file.rs"] mod imp;
+ } else if #[cfg(target_os = "illumos")] {
+ #[path = "solaris_illumos.rs"] mod imp;
+ } else if #[cfg(target_os = "ios")] {
+ #[path = "ios.rs"] mod imp;
+ } else if #[cfg(target_os = "linux")] {
+ #[path = "linux_android.rs"] mod imp;
+ } else if #[cfg(target_os = "macos")] {
+ #[path = "macos.rs"] mod imp;
+ } else if #[cfg(target_os = "netbsd")] {
+ #[path = "bsd_arandom.rs"] mod imp;
+ } else if #[cfg(target_os = "openbsd")] {
+ #[path = "openbsd.rs"] mod imp;
+ } else if #[cfg(target_os = "redox")] {
+ #[path = "use_file.rs"] mod imp;
+ } else if #[cfg(target_os = "solaris")] {
+ #[path = "solaris_illumos.rs"] mod imp;
+ } else if #[cfg(target_os = "wasi")] {
+ #[path = "wasi.rs"] mod imp;
+ } else if #[cfg(target_os = "vxworks")] {
+ #[path = "vxworks.rs"] mod imp;
+ } else if #[cfg(all(windows, getrandom_uwp))] {
+ #[path = "windows_uwp.rs"] mod imp;
+ } else if #[cfg(windows)] {
+ #[path = "windows.rs"] mod imp;
+ } else if #[cfg(all(target_arch = "x86_64", any(
+ target_os = "hermit",
+ target_os = "l4re",
+ target_os = "uefi",
+ target_env = "sgx",
+ )))] {
+ #[path = "rdrand.rs"] mod imp;
+ } else if #[cfg(all(target_arch = "wasm32", target_os = "unknown"))] {
+ cfg_if! {
+ if #[cfg(feature = "wasm-bindgen")] {
+ #[path = "wasm32_bindgen.rs"] mod imp;
+ } else if #[cfg(feature = "stdweb")] {
+ #[path = "wasm32_stdweb.rs"] mod imp;
+ } else {
+ // Always have an implementation for wasm32-unknown-unknown.
+ // See https://github.com/rust-random/getrandom/issues/87
+ #[path = "dummy.rs"] mod imp;
+ }
+ }
+ } else if #[cfg(feature = "dummy")] {
+ #[path = "dummy.rs"] mod imp;
+ } 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).
+pub fn getrandom(dest: &mut [u8]) -> Result<(), error::Error> {
+ if dest.is_empty() {
+ return Ok(());
+ }
+ imp::getrandom_inner(dest)
+}
diff --git a/src/linux_android.rs b/src/linux_android.rs
new file mode 100644
index 0000000..a29feb5
--- /dev/null
+++ b/src/linux_android.rs
@@ -0,0 +1,44 @@
+// 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;
+use crate::util_libc::{last_os_error, sys_fill_exact};
+use crate::{use_file, Error};
+
+pub fn getrandom_inner(dest: &mut [u8]) -> Result<(), Error> {
+ 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/src/macos.rs b/src/macos.rs
new file mode 100644
index 0000000..c3bc533
--- /dev/null
+++ b/src/macos.rs
@@ -0,0 +1,34 @@
+// 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::util_libc::{last_os_error, Weak};
+use crate::{use_file, Error};
+use core::mem;
+
+type GetEntropyFn = unsafe extern "C" fn(*mut u8, libc::size_t) -> libc::c_int;
+
+pub fn getrandom_inner(dest: &mut [u8]) -> Result<(), Error> {
+ 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(), chunk.len()) };
+ if ret != 0 {
+ let err = last_os_error();
+ error!("getentropy syscall failed");
+ return Err(err);
+ }
+ }
+ 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/src/openbsd.rs b/src/openbsd.rs
new file mode 100644
index 0000000..e1ac179
--- /dev/null
+++ b/src/openbsd.rs
@@ -0,0 +1,23 @@
+// 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;
+use crate::Error;
+
+pub fn getrandom_inner(dest: &mut [u8]) -> Result<(), Error> {
+ 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 {
+ let err = last_os_error();
+ error!("libc::getentropy call failed");
+ return Err(err);
+ }
+ }
+ Ok(())
+}
diff --git a/src/rdrand.rs b/src/rdrand.rs
new file mode 100644
index 0000000..e441682
--- /dev/null
+++ b/src/rdrand.rs
@@ -0,0 +1,90 @@
+// 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 SGX using RDRAND instruction
+use crate::error::{FAILED_RDRAND, NO_RDRAND};
+#[cfg(not(target_feature = "rdrand"))]
+use crate::util::LazyBool;
+use crate::Error;
+use core::arch::x86_64::_rdrand64_step;
+use core::mem;
+
+// 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;
+const WORD_SIZE: usize = mem::size_of::<u64>();
+
+#[target_feature(enable = "rdrand")]
+unsafe fn rdrand() -> Result<[u8; WORD_SIZE], Error> {
+ for _ in 0..RETRY_LIMIT {
+ let mut el = mem::zeroed();
+ if _rdrand64_step(&mut el) == 1 {
+ // AMD CPUs from families 14h to 16h (pre Ryzen) sometimes fail to
+ // set CF on bogus random data, so we check these values explicitly.
+ // See https://github.com/systemd/systemd/issues/11810#issuecomment-489727505
+ // We perform this check regardless of target to guard against
+ // any implementation that incorrectly fails to set CF.
+ if el != 0 && el != !0 {
+ return Ok(el.to_ne_bytes());
+ }
+ error!("RDRAND returned {:X}, CPU RNG may be broken", el);
+ // Keep looping in case this was a false positive.
+ }
+ }
+ Err(FAILED_RDRAND)
+}
+
+// "rdrand" target feature requires "+rdrnd" 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=+rdrnd."
+);
+
+#[cfg(target_feature = "rdrand")]
+fn is_rdrand_supported() -> bool {
+ true
+}
+
+// TODO use is_x86_feature_detected!("rdrand") when that works in core. See:
+// https://github.com/rust-lang-nursery/stdsimd/issues/464
+#[cfg(not(target_feature = "rdrand"))]
+fn is_rdrand_supported() -> bool {
+ use core::arch::x86_64::__cpuid;
+ // SAFETY: All x86_64 CPUs support CPUID leaf 1
+ const FLAG: u32 = 1 << 30;
+ static HAS_RDRAND: LazyBool = LazyBool::new();
+ HAS_RDRAND.unsync_init(|| unsafe { (__cpuid(1).ecx & FLAG) != 0 })
+}
+
+pub fn getrandom_inner(dest: &mut [u8]) -> Result<(), Error> {
+ if !is_rdrand_supported() {
+ return Err(NO_RDRAND);
+ }
+
+ // SAFETY: After this point, rdrand is supported, so calling the rdrand
+ // functions is not undefined behavior.
+ unsafe { rdrand_exact(dest) }
+}
+
+#[target_feature(enable = "rdrand")]
+unsafe fn rdrand_exact(dest: &mut [u8]) -> Result<(), Error> {
+ // 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(WORD_SIZE);
+ for chunk in chunks.by_ref() {
+ chunk.copy_from_slice(&rdrand()?);
+ }
+
+ let tail = chunks.into_remainder();
+ let n = tail.len();
+ if n > 0 {
+ tail.copy_from_slice(&rdrand()?[..n]);
+ }
+ Ok(())
+}
diff --git a/src/solaris_illumos.rs b/src/solaris_illumos.rs
new file mode 100644
index 0000000..9473123
--- /dev/null
+++ b/src/solaris_illumos.rs
@@ -0,0 +1,44 @@
+// 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
+//!
+//! Read from `/dev/random`, with chunks of limited size (256 bytes).
+//! `/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`.
+//!
+//! Since Solaris 11.3 and mid-2015 illumos, the `getrandom` syscall is available.
+//! 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::util_libc::{sys_fill_exact, Weak};
+use crate::{use_file, Error};
+use core::mem;
+
+#[cfg(target_os = "illumos")]
+type GetRandomFn = unsafe extern "C" fn(*mut u8, libc::size_t, libc::c_uint) -> libc::ssize_t;
+#[cfg(target_os = "solaris")]
+type GetRandomFn = unsafe extern "C" fn(*mut u8, libc::size_t, libc::c_uint) -> libc::c_int;
+
+pub fn getrandom_inner(dest: &mut [u8]) -> Result<(), Error> {
+ static GETRANDOM: Weak = unsafe { Weak::new("getrandom\0") };
+ 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 {
+ func(buf.as_mut_ptr(), buf.len(), 0) as libc::ssize_t
+ })?
+ }
+ Ok(())
+ } else {
+ use_file::getrandom_inner(dest)
+ }
+}
diff --git a/src/use_file.rs b/src/use_file.rs
new file mode 100644
index 0000000..6e50955
--- /dev/null
+++ b/src/use_file.rs
@@ -0,0 +1,137 @@
+// 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;
+use crate::util_libc::{open_readonly, sys_fill_exact};
+use crate::Error;
+use core::cell::UnsafeCell;
+use core::sync::atomic::{AtomicUsize, Ordering::Relaxed};
+
+#[cfg(target_os = "redox")]
+const FILE_PATH: &str = "rand:\0";
+#[cfg(any(
+ target_os = "dragonfly",
+ target_os = "emscripten",
+ target_os = "haiku",
+ target_os = "macos",
+ target_os = "solaris",
+ target_os = "illumos"
+))]
+const FILE_PATH: &str = "/dev/random\0";
+#[cfg(any(target_os = "android", target_os = "linux"))]
+const FILE_PATH: &str = "/dev/urandom\0";
+
+pub fn getrandom_inner(dest: &mut [u8]) -> Result<(), Error> {
+ let fd = get_rng_fd()?;
+ let read = |buf: &mut [u8]| unsafe { libc::read(fd, buf.as_mut_ptr() as *mut _, buf.len()) };
+
+ if cfg!(target_os = "emscripten") {
+ // `Crypto.getRandomValues` documents `dest` should be at most 65536 bytes.
+ for chunk in dest.chunks_mut(65536) {
+ sys_fill_exact(chunk, read)?;
+ }
+ } else {
+ sys_fill_exact(dest, read)?;
+ }
+ Ok(())
+}
+
+// Returns the file descriptor for the device file used to retrieve random
+// bytes. The file will be opened exactly once. All successful 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 {
+ 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/src/util.rs b/src/util.rs
new file mode 100644
index 0000000..8dbd8ae
--- /dev/null
+++ b/src/util.rs
@@ -0,0 +1,64 @@
+// 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.
+
+use core::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
+ }
+}
diff --git a/src/util_libc.rs b/src/util_libc.rs
new file mode 100644
index 0000000..1cdc13e
--- /dev/null
+++ b/src/util_libc.rs
@@ -0,0 +1,121 @@
+// 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.
+use crate::error::ERRNO_NOT_POSITIVE;
+use crate::util::LazyUsize;
+use crate::Error;
+use core::num::NonZeroU32;
+use core::ptr::NonNull;
+
+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;
+ }
+}
+
+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 {
+ 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 [u8],
+ sys_fill: impl Fn(&mut [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.
+ buf = &mut buf[(res as usize)..];
+ }
+ }
+ 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.
+// F must be a function pointer of type `unsafe extern "C" fn`. Based off of the
+// weak! macro in libstd.
+pub struct Weak {
+ name: &'static str,
+ addr: LazyUsize,
+}
+
+impl Weak {
+ // 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: LazyUsize::new(),
+ }
+ }
+
+ // Return a function pointer if present at runtime. Otherwise, return null.
+ pub fn ptr(&self) -> Option<NonNull<libc::c_void>> {
+ let addr = self.addr.unsync_init(|| unsafe {
+ libc::dlsym(libc::RTLD_DEFAULT, self.name.as_ptr() as *const _) as usize
+ });
+ NonNull::new(addr as *mut _)
+ }
+}
+
+cfg_if! {
+ if #[cfg(any(target_os = "linux", target_os = "emscripten"))] {
+ use libc::open64 as open;
+ } else {
+ use libc::open;
+ }
+}
+
+// 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!(path.as_bytes().last() == Some(&0));
+ let fd = open(path.as_ptr() as *const _, libc::O_RDONLY | libc::O_CLOEXEC);
+ if fd < 0 {
+ return Err(last_os_error());
+ }
+ // O_CLOEXEC works on all Unix targets except for older Linux kernels (pre
+ // 2.6.23), so we also use an ioctl to make sure FD_CLOEXEC is set.
+ #[cfg(target_os = "linux")]
+ libc::ioctl(fd, libc::FIOCLEX);
+ Ok(fd)
+}
diff --git a/src/vxworks.rs b/src/vxworks.rs
new file mode 100644
index 0000000..a2fe52a
--- /dev/null
+++ b/src/vxworks.rs
@@ -0,0 +1,35 @@
+// 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::error::{Error, RAND_SECURE_FATAL};
+use crate::util_libc::last_os_error;
+use core::sync::atomic::{AtomicBool, Ordering::Relaxed};
+
+pub fn getrandom_inner(dest: &mut [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(RAND_SECURE_FATAL);
+ } 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(), chunk.len() as i32) };
+ if ret != 0 {
+ return Err(last_os_error());
+ }
+ }
+ Ok(())
+}
diff --git a/src/wasi.rs b/src/wasi.rs
new file mode 100644
index 0000000..4674f43
--- /dev/null
+++ b/src/wasi.rs
@@ -0,0 +1,19 @@
+// 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::num::NonZeroU32;
+use wasi::random_get;
+
+pub fn getrandom_inner(dest: &mut [u8]) -> Result<(), Error> {
+ unsafe { random_get(dest.as_mut_ptr(), dest.len()) }.map_err(|e: wasi::Error| {
+ // convert wasi's Error into getrandom's NonZeroU32 error
+ NonZeroU32::new(e.raw_error() as u32).unwrap().into()
+ })
+}
diff --git a/src/wasm32_bindgen.rs b/src/wasm32_bindgen.rs
new file mode 100644
index 0000000..86839a0
--- /dev/null
+++ b/src/wasm32_bindgen.rs
@@ -0,0 +1,113 @@
+// 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 WASM via wasm-bindgen
+extern crate std;
+
+use core::cell::RefCell;
+use core::mem;
+use std::thread_local;
+
+use wasm_bindgen::prelude::*;
+
+use crate::error::{BINDGEN_CRYPTO_UNDEF, BINDGEN_GRV_UNDEF};
+use crate::Error;
+
+#[derive(Clone, Debug)]
+enum RngSource {
+ Node(NodeCrypto),
+ Browser(BrowserCrypto),
+}
+
+// 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: RefCell<Option<RngSource>> = RefCell::new(None);
+);
+
+pub fn getrandom_inner(dest: &mut [u8]) -> Result<(), Error> {
+ assert_eq!(mem::size_of::<usize>(), 4);
+
+ RNG_SOURCE.with(|f| {
+ let mut source = f.borrow_mut();
+ if source.is_none() {
+ *source = Some(getrandom_init()?);
+ }
+
+ match source.as_ref().unwrap() {
+ RngSource::Node(n) => n.random_fill_sync(dest),
+ RngSource::Browser(n) => {
+ // see https://developer.mozilla.org/en-US/docs/Web/API/Crypto/getRandomValues
+ //
+ // where it says:
+ //
+ // > A QuotaExceededError DOMException is thrown if the
+ // > requested length is greater than 65536 bytes.
+ for chunk in dest.chunks_mut(65536) {
+ n.get_random_values(chunk)
+ }
+ }
+ };
+ Ok(())
+ })
+}
+
+fn getrandom_init() -> Result<RngSource, Error> {
+ if let Ok(self_) = Global::get_self() {
+ // If `self` is defined then we're in a browser somehow (main window
+ // or web worker). Here we want to try to use
+ // `crypto.getRandomValues`, but if `crypto` isn't defined we assume
+ // we're in an older web browser and the OS RNG isn't available.
+
+ let crypto = self_.crypto();
+ if crypto.is_undefined() {
+ return Err(BINDGEN_CRYPTO_UNDEF);
+ }
+
+ // Test if `crypto.getRandomValues` is undefined as well
+ let crypto: BrowserCrypto = crypto.into();
+ if crypto.get_random_values_fn().is_undefined() {
+ return Err(BINDGEN_GRV_UNDEF);
+ }
+
+ return Ok(RngSource::Browser(crypto));
+ }
+
+ return Ok(RngSource::Node(node_require("crypto")));
+}
+
+#[wasm_bindgen]
+extern "C" {
+ type Global;
+ #[wasm_bindgen(getter, catch, static_method_of = Global, js_class = self, js_name = self)]
+ fn get_self() -> Result<Self_, JsValue>;
+
+ type Self_;
+ #[wasm_bindgen(method, getter, structural)]
+ fn crypto(me: &Self_) -> JsValue;
+
+ #[derive(Clone, Debug)]
+ type BrowserCrypto;
+
+ // TODO: these `structural` annotations here ideally wouldn't be here to
+ // avoid a JS shim, but for now with feature detection they're
+ // unavoidable.
+ #[wasm_bindgen(method, js_name = getRandomValues, structural, getter)]
+ fn get_random_values_fn(me: &BrowserCrypto) -> JsValue;
+ #[wasm_bindgen(method, js_name = getRandomValues, structural)]
+ fn get_random_values(me: &BrowserCrypto, buf: &mut [u8]);
+
+ #[wasm_bindgen(js_name = require)]
+ fn node_require(s: &str) -> NodeCrypto;
+
+ #[derive(Clone, Debug)]
+ type NodeCrypto;
+
+ #[wasm_bindgen(method, js_name = randomFillSync, structural)]
+ fn random_fill_sync(me: &NodeCrypto, buf: &mut [u8]);
+}
diff --git a/src/wasm32_stdweb.rs b/src/wasm32_stdweb.rs
new file mode 100644
index 0000000..6e5e78a
--- /dev/null
+++ b/src/wasm32_stdweb.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.
+
+//! Implementation for WASM via stdweb
+extern crate std;
+
+use core::mem;
+
+use stdweb::js;
+use stdweb::unstable::TryInto;
+use stdweb::web::error::Error as WebError;
+
+use crate::error::{STDWEB_NO_RNG, STDWEB_RNG_FAILED};
+use crate::Error;
+use std::sync::Once;
+
+#[derive(Clone, Copy, Debug)]
+enum RngSource {
+ Browser,
+ Node,
+}
+
+pub fn getrandom_inner(dest: &mut [u8]) -> Result<(), Error> {
+ assert_eq!(mem::size_of::<usize>(), 4);
+ static ONCE: Once = Once::new();
+ static mut RNG_SOURCE: Result<RngSource, Error> = Ok(RngSource::Node);
+
+ // SAFETY: RNG_SOURCE is only written once, before being read.
+ ONCE.call_once(|| unsafe {
+ RNG_SOURCE = getrandom_init();
+ });
+ getrandom_fill(unsafe { RNG_SOURCE }?, dest)
+}
+
+fn getrandom_init() -> Result<RngSource, Error> {
+ let result = js! {
+ try {
+ if (
+ typeof self === "object" &&
+ typeof self.crypto === "object" &&
+ typeof self.crypto.getRandomValues === "function"
+ ) {
+ return { success: true, ty: 1 };
+ }
+
+ if (typeof require("crypto").randomBytes === "function") {
+ return { success: true, ty: 2 };
+ }
+
+ return { success: false, error: new Error("not supported") };
+ } catch(err) {
+ return { success: false, error: err };
+ }
+ };
+
+ if js! { return @{ result.as_ref() }.success } == true {
+ let ty = js! { return @{ result }.ty };
+
+ if ty == 1 {
+ Ok(RngSource::Browser)
+ } else if ty == 2 {
+ Ok(RngSource::Node)
+ } else {
+ unreachable!()
+ }
+ } else {
+ let _err: WebError = js! { return @{ result }.error }.try_into().unwrap();
+ error!("getrandom unavailable: {}", _err);
+ Err(STDWEB_NO_RNG)
+ }
+}
+
+fn getrandom_fill(source: RngSource, dest: &mut [u8]) -> Result<(), Error> {
+ for chunk in dest.chunks_mut(65536) {
+ let len = chunk.len() as u32;
+ let ptr = chunk.as_mut_ptr() as i32;
+
+ let result = match source {
+ RngSource::Browser => js! {
+ try {
+ let array = new Uint8Array(@{ len });
+ self.crypto.getRandomValues(array);
+ HEAPU8.set(array, @{ ptr });
+
+ return { success: true };
+ } catch(err) {
+ return { success: false, error: err };
+ }
+ },
+ RngSource::Node => js! {
+ try {
+ let bytes = require("crypto").randomBytes(@{ len });
+ HEAPU8.set(new Uint8Array(bytes), @{ ptr });
+
+ return { success: true };
+ } catch(err) {
+ return { success: false, error: err };
+ }
+ },
+ };
+
+ if js! { return @{ result.as_ref() }.success } != true {
+ let _err: WebError = js! { return @{ result }.error }.try_into().unwrap();
+ error!("getrandom failed: {}", _err);
+ return Err(STDWEB_RNG_FAILED);
+ }
+ }
+ Ok(())
+}
diff --git a/src/windows.rs b/src/windows.rs
new file mode 100644
index 0000000..e1b8df6
--- /dev/null
+++ b/src/windows.rs
@@ -0,0 +1,26 @@
+// 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 Windows
+use crate::{error::RTL_GEN_RANDOM_FAILED, Error};
+
+extern "system" {
+ #[link_name = "SystemFunction036"]
+ fn RtlGenRandom(RandomBuffer: *mut u8, RandomBufferLength: u32) -> u8;
+}
+
+pub fn getrandom_inner(dest: &mut [u8]) -> Result<(), Error> {
+ // Prevent overflow of u32
+ for chunk in dest.chunks_mut(u32::max_value() as usize) {
+ let ret = unsafe { RtlGenRandom(chunk.as_mut_ptr(), chunk.len() as u32) };
+ if ret == 0 {
+ return Err(RTL_GEN_RANDOM_FAILED);
+ }
+ }
+ Ok(())
+}
diff --git a/src/windows_uwp.rs b/src/windows_uwp.rs
new file mode 100644
index 0000000..586c6f6
--- /dev/null
+++ b/src/windows_uwp.rs
@@ -0,0 +1,59 @@
+// 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 Windows UWP targets. After deprecation of Windows XP
+//! and Vista, this can supersede the `RtlGenRandom`-based implementation.
+use crate::Error;
+use core::{ffi::c_void, num::NonZeroU32, ptr};
+
+const BCRYPT_USE_SYSTEM_PREFERRED_RNG: u32 = 0x00000002;
+
+extern "system" {
+ fn BCryptGenRandom(
+ hAlgorithm: *mut c_void,
+ pBuffer: *mut u8,
+ cbBuffer: u32,
+ dwFlags: u32,
+ ) -> u32;
+}
+
+pub fn getrandom_inner(dest: &mut [u8]) -> Result<(), Error> {
+ // Prevent overflow of u32
+ for chunk in dest.chunks_mut(u32::max_value() as usize) {
+ let ret = unsafe {
+ BCryptGenRandom(
+ ptr::null_mut(),
+ chunk.as_mut_ptr(),
+ chunk.len() as u32,
+ BCRYPT_USE_SYSTEM_PREFERRED_RNG,
+ )
+ };
+ // NTSTATUS codes use two highest bits for severity status
+ match ret >> 30 {
+ 0b01 => {
+ info!("BCryptGenRandom: information code 0x{:08X}", ret);
+ }
+ 0b10 => {
+ warn!("BCryptGenRandom: warning code 0x{:08X}", ret);
+ }
+ 0b11 => {
+ error!("BCryptGenRandom: failed with 0x{:08X}", ret);
+ // We zeroize the highest bit, so the error code will reside
+ // inside the range of 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 compiler
+ // is not smart enough to figure out it yet.
+ let code = unsafe { NonZeroU32::new_unchecked(code) };
+ return Err(Error::from(code));
+ }
+ _ => (),
+ }
+ }
+ Ok(())
+}
diff --git a/tests/common.rs b/tests/common.rs
new file mode 100644
index 0000000..afefa03
--- /dev/null
+++ b/tests/common.rs
@@ -0,0 +1,68 @@
+#[cfg(feature = "wasm-bindgen")]
+use wasm_bindgen_test::*;
+
+use getrandom::getrandom;
+
+#[cfg(feature = "test-in-browser")]
+wasm_bindgen_test_configure!(run_in_browser);
+
+#[cfg_attr(feature = "wasm-bindgen", wasm_bindgen_test)]
+#[test]
+fn test_zero() {
+ // Test that APIs are happy with zero-length requests
+ getrandom(&mut [0u8; 0]).unwrap();
+}
+
+#[cfg_attr(feature = "wasm-bindgen", wasm_bindgen_test)]
+#[test]
+fn test_diff() {
+ let mut v1 = [0u8; 1000];
+ getrandom(&mut v1).unwrap();
+
+ let mut v2 = [0u8; 1000];
+ getrandom(&mut v2).unwrap();
+
+ let mut n_diff_bits = 0;
+ for i in 0..v1.len() {
+ n_diff_bits += (v1[i] ^ v2[i]).count_ones();
+ }
+
+ // Check at least 1 bit per byte differs. p(failure) < 1e-1000 with random input.
+ assert!(n_diff_bits >= v1.len() as u32);
+}
+
+#[cfg_attr(feature = "wasm-bindgen", wasm_bindgen_test)]
+#[test]
+fn test_huge() {
+ let mut huge = [0u8; 100_000];
+ getrandom(&mut huge).unwrap();
+}
+
+#[cfg(any(unix, windows, target_os = "redox", target_os = "fuchsia"))]
+#[test]
+fn test_multithreading() {
+ use std::sync::mpsc::channel;
+ use std::thread;
+
+ let mut txs = vec![];
+ for _ in 0..20 {
+ let (tx, rx) = channel();
+ txs.push(tx);
+
+ thread::spawn(move || {
+ // wait until all the tasks are ready to go.
+ rx.recv().unwrap();
+ let mut v = [0u8; 1000];
+
+ for _ in 0..100 {
+ getrandom(&mut v).unwrap();
+ thread::yield_now();
+ }
+ });
+ }
+
+ // start all the tasks
+ for tx in txs.iter() {
+ tx.send(()).unwrap();
+ }
+}
