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-rw-r--r--getrandom/src/bsd_arandom.rs49
-rw-r--r--getrandom/src/cloudabi.rs25
-rw-r--r--getrandom/src/dummy.rs14
-rw-r--r--getrandom/src/error.rs178
-rw-r--r--getrandom/src/error_impls.rs35
-rw-r--r--getrandom/src/fuchsia.rs20
-rw-r--r--getrandom/src/ios.rs31
-rw-r--r--getrandom/src/lib.rs282
-rw-r--r--getrandom/src/linux_android.rs44
-rw-r--r--getrandom/src/macos.rs34
-rw-r--r--getrandom/src/openbsd.rs23
-rw-r--r--getrandom/src/rdrand.rs90
-rw-r--r--getrandom/src/solaris_illumos.rs44
-rw-r--r--getrandom/src/use_file.rs73
-rw-r--r--getrandom/src/util.rs96
-rw-r--r--getrandom/src/util_libc.rs143
-rw-r--r--getrandom/src/vxworks.rs35
-rw-r--r--getrandom/src/wasi.rs19
-rw-r--r--getrandom/src/wasm32_bindgen.rs113
-rw-r--r--getrandom/src/wasm32_stdweb.rs114
-rw-r--r--getrandom/src/windows.rs26
-rw-r--r--getrandom/src/windows_uwp.rs59
22 files changed, 1547 insertions, 0 deletions
diff --git a/getrandom/src/bsd_arandom.rs b/getrandom/src/bsd_arandom.rs
new file mode 100644
index 0000000..eb564ff
--- /dev/null
+++ b/getrandom/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/getrandom/src/cloudabi.rs b/getrandom/src/cloudabi.rs
new file mode 100644
index 0000000..d3d0928
--- /dev/null
+++ b/getrandom/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/getrandom/src/dummy.rs b/getrandom/src/dummy.rs
new file mode 100644
index 0000000..0c24ba0
--- /dev/null
+++ b/getrandom/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/getrandom/src/error.rs b/getrandom/src/error.rs
new file mode 100644
index 0000000..b2cb9a8
--- /dev/null
+++ b/getrandom/src/error.rs
@@ -0,0 +1,178 @@
+// 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_desc(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_desc(errno: i32, _buf: &mut [u8]) -> Option<&str> {
+ core::num::NonZeroU16::new(errno as u16)
+ .and_then(wasi::wasi_unstable::error_str)
+ }
+ } else {
+ fn os_err_desc(_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(desc) = os_err_desc(errno, &mut buf) {
+ dbg.field("description", &desc);
+ }
+ } 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_desc(errno, &mut buf) {
+ Some(desc) => f.write_str(desc),
+ 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/getrandom/src/error_impls.rs b/getrandom/src/error_impls.rs
new file mode 100644
index 0000000..007472e
--- /dev/null
+++ b/getrandom/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/getrandom/src/fuchsia.rs b/getrandom/src/fuchsia.rs
new file mode 100644
index 0000000..572ff53
--- /dev/null
+++ b/getrandom/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/getrandom/src/ios.rs b/getrandom/src/ios.rs
new file mode 100644
index 0000000..30c008c
--- /dev/null
+++ b/getrandom/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/getrandom/src/lib.rs b/getrandom/src/lib.rs
new file mode 100644
index 0000000..c305406
--- /dev/null
+++ b/getrandom/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&section=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/getrandom/src/linux_android.rs b/getrandom/src/linux_android.rs
new file mode 100644
index 0000000..a29feb5
--- /dev/null
+++ b/getrandom/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/getrandom/src/macos.rs b/getrandom/src/macos.rs
new file mode 100644
index 0000000..c3bc533
--- /dev/null
+++ b/getrandom/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/getrandom/src/openbsd.rs b/getrandom/src/openbsd.rs
new file mode 100644
index 0000000..e1ac179
--- /dev/null
+++ b/getrandom/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/getrandom/src/rdrand.rs b/getrandom/src/rdrand.rs
new file mode 100644
index 0000000..e441682
--- /dev/null
+++ b/getrandom/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/getrandom/src/solaris_illumos.rs b/getrandom/src/solaris_illumos.rs
new file mode 100644
index 0000000..9473123
--- /dev/null
+++ b/getrandom/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/getrandom/src/use_file.rs b/getrandom/src/use_file.rs
new file mode 100644
index 0000000..d3adaf2
--- /dev/null
+++ b/getrandom/src/use_file.rs
@@ -0,0 +1,73 @@
+// 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_libc::{last_os_error, open_readonly, sys_fill_exact, LazyFd};
+use crate::Error;
+
+#[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";
+
+pub fn getrandom_inner(dest: &mut [u8]) -> Result<(), Error> {
+ static FD: LazyFd = LazyFd::new();
+ let fd = FD.init(init_file).ok_or_else(last_os_error)?;
+ 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(())
+}
+
+cfg_if! {
+ if #[cfg(any(target_os = "android", target_os = "linux"))] {
+ fn init_file() -> Option<libc::c_int> {
+ // Poll /dev/random to make sure it is ok to read from /dev/urandom.
+ let mut pfd = libc::pollfd {
+ fd: unsafe { open_readonly("/dev/random\0")? },
+ events: libc::POLLIN,
+ revents: 0,
+ };
+
+ let ret = loop {
+ // A negative timeout means an infinite timeout.
+ let res = unsafe { libc::poll(&mut pfd, 1, -1) };
+ if res == 1 {
+ break unsafe { open_readonly("/dev/urandom\0") };
+ } else if res < 0 {
+ let e = last_os_error().raw_os_error();
+ if e == Some(libc::EINTR) || e == Some(libc::EAGAIN) {
+ continue;
+ }
+ }
+ // We either hard failed, or poll() returned the wrong pfd.
+ break None;
+ };
+ unsafe { libc::close(pfd.fd) };
+ ret
+ }
+ } else {
+ fn init_file() -> Option<libc::c_int> {
+ unsafe { open_readonly(FILE_PATH) }
+ }
+ }
+}
diff --git a/getrandom/src/util.rs b/getrandom/src/util.rs
new file mode 100644
index 0000000..e0e9307
--- /dev/null
+++ b/getrandom/src/util.rs
@@ -0,0 +1,96 @@
+// 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();
+ // The initialization is currently running.
+ pub const ACTIVE: usize = usize::max_value() - 1;
+
+ // 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
+ }
+
+ // Synchronously runs the init() function. Only one caller will have their
+ // init() function running at a time, and exactly one successful call will
+ // be run. init() returning UNINIT or ACTIVE will be considered a failure,
+ // and future calls to sync_init will rerun their init() function.
+ pub fn sync_init(&self, init: impl FnOnce() -> usize, mut wait: impl FnMut()) -> usize {
+ // Common and fast path with no contention. Don't wast time on CAS.
+ match self.0.load(Relaxed) {
+ Self::UNINIT | Self::ACTIVE => {}
+ val => return val,
+ }
+ // Relaxed ordering is fine, as we only have a single atomic variable.
+ loop {
+ match self.0.compare_and_swap(Self::UNINIT, Self::ACTIVE, Relaxed) {
+ Self::UNINIT => {
+ let val = init();
+ self.0.store(
+ match val {
+ Self::UNINIT | Self::ACTIVE => Self::UNINIT,
+ val => val,
+ },
+ Relaxed,
+ );
+ return val;
+ }
+ Self::ACTIVE => wait(),
+ val => return 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/getrandom/src/util_libc.rs b/getrandom/src/util_libc.rs
new file mode 100644
index 0000000..5a05170
--- /dev/null
+++ b/getrandom/src/util_libc.rs
@@ -0,0 +1,143 @@
+// 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", target_os = "dragonfly"))] {
+ use libc::__error as errno_location;
+ } else if #[cfg(target_os = "haiku")] {
+ use libc::_errnop as errno_location;
+ }
+}
+
+pub fn last_os_error() -> Error {
+ #[cfg(not(target_os = "vxworks"))]
+ let errno = unsafe { *errno_location() };
+ #[cfg(target_os = "vxworks")]
+ let errno = unsafe { libc::errnoGet() };
+ 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 _)
+ }
+}
+
+pub struct LazyFd(LazyUsize);
+
+impl LazyFd {
+ pub const fn new() -> Self {
+ Self(LazyUsize::new())
+ }
+
+ // If init() returns Some(x), x should be nonnegative.
+ pub fn init(&self, init: impl FnOnce() -> Option<libc::c_int>) -> Option<libc::c_int> {
+ let fd = self.0.sync_init(
+ || match init() {
+ // OK as val >= 0 and val <= c_int::MAX < usize::MAX
+ Some(val) => val as usize,
+ None => LazyUsize::UNINIT,
+ },
+ || unsafe {
+ // We are usually waiting on an open(2) syscall to complete,
+ // which typically takes < 10us if the file is a device.
+ // However, we might end up waiting much longer if the entropy
+ // pool isn't initialized, but even in that case, this loop will
+ // consume a negligible amount of CPU on most platforms.
+ libc::usleep(10);
+ },
+ );
+ match fd {
+ LazyUsize::UNINIT => None,
+ val => Some(val as libc::c_int),
+ }
+ }
+}
+
+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) -> Option<libc::c_int> {
+ debug_assert!(path.as_bytes().last() == Some(&0));
+ let fd = open(path.as_ptr() as *mut _, libc::O_RDONLY | libc::O_CLOEXEC);
+ if fd < 0 {
+ return None;
+ }
+ // 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);
+ Some(fd)
+}
diff --git a/getrandom/src/vxworks.rs b/getrandom/src/vxworks.rs
new file mode 100644
index 0000000..a2fe52a
--- /dev/null
+++ b/getrandom/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/getrandom/src/wasi.rs b/getrandom/src/wasi.rs
new file mode 100644
index 0000000..713c1ab
--- /dev/null
+++ b/getrandom/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;
+use wasi::wasi_unstable::random_get;
+
+pub fn getrandom_inner(dest: &mut [u8]) -> Result<(), Error> {
+ random_get(dest).map_err(|e: num::NonZeroU16| {
+ // convert wasi's NonZeroU16 error into getrandom's NonZeroU32 error
+ num::NonZeroU32::new(e.get() as u32).unwrap().into()
+ })
+}
diff --git a/getrandom/src/wasm32_bindgen.rs b/getrandom/src/wasm32_bindgen.rs
new file mode 100644
index 0000000..86839a0
--- /dev/null
+++ b/getrandom/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/getrandom/src/wasm32_stdweb.rs b/getrandom/src/wasm32_stdweb.rs
new file mode 100644
index 0000000..6e5e78a
--- /dev/null
+++ b/getrandom/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/getrandom/src/windows.rs b/getrandom/src/windows.rs
new file mode 100644
index 0000000..e1b8df6
--- /dev/null
+++ b/getrandom/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/getrandom/src/windows_uwp.rs b/getrandom/src/windows_uwp.rs
new file mode 100644
index 0000000..586c6f6
--- /dev/null
+++ b/getrandom/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(())
+}
generated by cgit v1.2.3 (git 2.46.0) at 2024-11-01 04:29:53 +0000