rand_core-0.5.1/CHANGELOG.md010064400017500001750000000043301353146424500135120ustar0000000000000000# 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). ## [0.5.1] - 2019-08-28 - `OsRng` added to `rand_core` (#863) - `Error::INTERNAL_START` and `Error::CUSTOM_START` constants (#864) - `Error::raw_os_error` method (#864) - `Debug` and `Display` formatting for `getrandom` error codes without `std` (#864) ### Changed - `alloc` feature in `no_std` is available since Rust 1.36 (#856) - Added `#[inline]` to `Error` conversion methods (#864) ## [0.5.0] - 2019-06-06 ### Changed - Enable testing with Miri and fix incorrect pointer usages (#779, #780, #781, #783, #784) - Rewrite `Error` type and adjust API (#800) - Adjust usage of `#[inline]` for `BlockRng` and `BlockRng64` ## [0.4.0] - 2019-01-24 ### Changed - Disable the `std` feature by default (#702) ## [0.3.0] - 2018-09-24 ### Added - Add `SeedableRng::seed_from_u64` for convenient seeding. (#537) ## [0.2.1] - 2018-06-08 ### Added - References to a `CryptoRng` now also implement `CryptoRng`. (#470) ## [0.2.0] - 2018-05-21 ### Changed - Enable the `std` feature by default. (#409) - Remove `BlockRng{64}::inner` and `BlockRng::inner_mut`; instead making `core` public - Change `BlockRngCore::Results` bound to also require `AsMut<[Self::Item]>`. (#419) ### Added - Add `BlockRng{64}::index` and `BlockRng{64}::generate_and_set`. (#374, #419) - Implement `std::io::Read` for RngCore. (#434) ## [0.1.0] - 2018-04-17 (Split out of the Rand crate, changes here are relative to rand 0.4.2.) ### Added - `RngCore` and `SeedableRng` are now part of `rand_core`. (#288) - Add modules to help implementing RNGs `impl` and `le`. (#209, #228) - Add `Error` and `ErrorKind`. (#225) - Add `CryptoRng` marker trait. (#273) - Add `BlockRngCore` trait. (#281) - Add `BlockRng` and `BlockRng64` wrappers to help implementations. (#281, #325) - Add `RngCore::try_fill_bytes`. (#225) ### Changed - Revise the `SeedableRng` trait. (#233) - Remove default implementations for `RngCore::next_u64` and `RngCore::fill_bytes`. (#288) ## [0.0.1] - 2017-09-14 (yanked) Experimental version as part of the rand crate refactor. rand_core-0.5.1/COPYRIGHT010064400017500001750000000010711345735742200132000ustar0000000000000000Copyrights in the Rand project are retained by their contributors. No copyright assignment is required to contribute to the Rand project. For full authorship information, see the version control history. Except as otherwise noted (below and/or in individual files), Rand is licensed under the Apache License, Version 2.0 or or the MIT license or , at your option. The Rand project includes code from the Rust project published under these same licenses. rand_core-0.5.1/Cargo.toml.orig010064400017500001750000000017101353146424500145670ustar0000000000000000[package] name = "rand_core" version = "0.5.1" authors = ["The Rand Project Developers", "The Rust Project Developers"] license = "MIT OR Apache-2.0" readme = "README.md" repository = "https://github.com/rust-random/rand" documentation = "https://rust-random.github.io/rand/rand_core/" homepage = "https://crates.io/crates/rand_core" description = """ Core random number generator traits and tools for implementation. """ keywords = ["random", "rng"] categories = ["algorithms", "no-std"] edition = "2018" [badges] travis-ci = { repository = "rust-random/rand" } appveyor = { repository = "rust-random/rand" } [features] std = ["alloc", "getrandom", "getrandom/std"] # use std library; should be default but for above bug alloc = [] # enables Vec and Box support without std serde1 = ["serde"] # enables serde for BlockRng wrapper [dependencies] serde = { version = "1", features = ["derive"], optional = true } getrandom = { version = "0.1", optional = true } rand_core-0.5.1/Cargo.toml0000644000000025040000000000000110310ustar00# 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 = "rand_core" version = "0.5.1" authors = ["The Rand Project Developers", "The Rust Project Developers"] description = "Core random number generator traits and tools for implementation.\n" homepage = "https://crates.io/crates/rand_core" documentation = "https://rust-random.github.io/rand/rand_core/" readme = "README.md" keywords = ["random", "rng"] categories = ["algorithms", "no-std"] license = "MIT OR Apache-2.0" repository = "https://github.com/rust-random/rand" [dependencies.getrandom] version = "0.1" optional = true [dependencies.serde] version = "1" features = ["derive"] optional = true [features] alloc = [] serde1 = ["serde"] std = ["alloc", "getrandom", "getrandom/std"] [badges.appveyor] repository = "rust-random/rand" [badges.travis-ci] repository = "rust-random/rand" rand_core-0.5.1/LICENSE-APACHE010064400017500001750000000251411346725354500136370ustar0000000000000000 Apache License Version 2.0, January 2004 https://www.apache.org/licenses/ TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION 1. 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See the License for the specific language governing permissions and limitations under the License. rand_core-0.5.1/LICENSE-MIT010064400017500001750000000021351347154030000133240ustar0000000000000000Copyright 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. 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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. rand_core-0.5.1/README.md010064400017500001750000000071241352222772600131650ustar0000000000000000# rand_core [![Build Status](https://travis-ci.org/rust-random/rand.svg)](https://travis-ci.org/rust-random/rand) [![Build Status](https://ci.appveyor.com/api/projects/status/github/rust-random/rand?svg=true)](https://ci.appveyor.com/project/rust-random/rand) [![Latest version](https://img.shields.io/crates/v/rand_core.svg)](https://crates.io/crates/rand_core) [![Book](https://img.shields.io/badge/book-master-yellow.svg)](https://rust-random.github.io/book/) [![API](https://img.shields.io/badge/api-master-yellow.svg)](https://rust-random.github.io/rand/rand_core) [![API](https://docs.rs/rand_core/badge.svg)](https://docs.rs/rand_core) [![Minimum rustc version](https://img.shields.io/badge/rustc-1.32+-lightgray.svg)](https://github.com/rust-random/rand#rust-version-requirements) Core traits and error types of the [rand] library, plus tools for implementing RNGs. This crate is intended for use when implementing the core trait, `RngCore`; it defines the core traits to be implemented as well as several small functions to aid in their implementation and types required for error handling. The main [rand] crate re-exports most items defined in this crate, along with tools to convert the integer samples generated by `RngCore` to many different applications (including sampling from restricted ranges, conversion to floating point, list permutations and secure initialisation of RNGs). Most users should prefer to use the main [rand] crate. Links: - [API documentation (master)](https://rust-random.github.io/rand/rand_core) - [API documentation (docs.rs)](https://docs.rs/rand_core) - [Changelog](https://github.com/rust-random/rand/blob/master/rand_core/CHANGELOG.md) [rand]: https://crates.io/crates/rand ## Functionality The `rand_core` crate provides: - base random number generator traits - error-reporting types - functionality to aid implementation of RNGs The traits and error types are also available via `rand`. ## Versions The current version is: ``` rand_core = "0.5.0" ``` Rand libs have inter-dependencies and make use of the [semver trick](https://github.com/dtolnay/semver-trick/) in order to make traits compatible across crate versions. (This is especially important for `RngCore` and `SeedableRng`.) A few crate releases are thus compatibility shims, depending on the *next* lib version (e.g. `rand_core` versions `0.2.2` and `0.3.1`). This means, for example, that `rand_core_0_4_0::SeedableRng` and `rand_core_0_3_0::SeedableRng` are distinct, incompatible traits, which can cause build errors. Usually, running `cargo update` is enough to fix any issues. ## Crate Features `rand_core` supports `no_std` and `alloc`-only configurations, as well as full `std` functionality. The differences between `no_std` and full `std` are small, comprising `RngCore` support for `Box` types where `R: RngCore`, `std::io::Read` support for types supporting `RngCore`, and extensions to the `Error` type's functionality. The `std` feature is *not enabled by default*. This is primarily to avoid build problems where one crate implicitly requires `rand_core` with `std` support and another crate requires `rand` *without* `std` support. However, the `rand` crate continues to enable `std` support by default, both for itself and `rand_core`. The `serde1` feature can be used to derive `Serialize` and `Deserialize` for RNG implementations that use the `BlockRng` or `BlockRng64` wrappers. # License `rand_core` is distributed under the terms of both the MIT license and the Apache License (Version 2.0). See [LICENSE-APACHE](LICENSE-APACHE) and [LICENSE-MIT](LICENSE-MIT), and [COPYRIGHT](COPYRIGHT) for details. rand_core-0.5.1/src/block.rs010064400017500001750000000350121352222772600141320ustar0000000000000000// Copyright 2018 Developers of the Rand project. // // Licensed under the Apache License, Version 2.0 or the MIT license // , at your // option. This file may not be copied, modified, or distributed // except according to those terms. //! The `BlockRngCore` trait and implementation helpers //! //! The [`BlockRngCore`] trait exists to assist in the implementation of RNGs //! which generate a block of data in a cache instead of returning generated //! values directly. //! //! Usage of this trait is optional, but provides two advantages: //! implementations only need to concern themselves with generation of the //! block, not the various [`RngCore`] methods (especially [`fill_bytes`], where //! the optimal implementations are not trivial), and this allows //! `ReseedingRng` (see [`rand`](https://docs.rs/rand) crate) perform periodic //! reseeding with very low overhead. //! //! # Example //! //! ```norun //! use rand_core::block::{BlockRngCore, BlockRng}; //! //! struct MyRngCore; //! //! impl BlockRngCore for MyRngCore { //! type Results = [u32; 16]; //! //! fn generate(&mut self, results: &mut Self::Results) { //! unimplemented!() //! } //! } //! //! impl SeedableRng for MyRngCore { //! type Seed = unimplemented!(); //! fn from_seed(seed: Self::Seed) -> Self { //! unimplemented!() //! } //! } //! //! // optionally, also implement CryptoRng for MyRngCore //! //! // Final RNG. //! type MyRng = BlockRng; //! ``` //! //! [`BlockRngCore`]: crate::block::BlockRngCore //! [`fill_bytes`]: RngCore::fill_bytes use core::convert::AsRef; use core::{fmt, ptr}; #[cfg(feature="serde1")] use serde::{Serialize, Deserialize}; use crate::{RngCore, CryptoRng, SeedableRng, Error}; use crate::impls::{fill_via_u32_chunks, fill_via_u64_chunks}; /// A trait for RNGs which do not generate random numbers individually, but in /// blocks (typically `[u32; N]`). This technique is commonly used by /// cryptographic RNGs to improve performance. /// /// See the [module][crate::block] documentation for details. pub trait BlockRngCore { /// Results element type, e.g. `u32`. type Item; /// Results type. This is the 'block' an RNG implementing `BlockRngCore` /// generates, which will usually be an array like `[u32; 16]`. type Results: AsRef<[Self::Item]> + AsMut<[Self::Item]> + Default; /// Generate a new block of results. fn generate(&mut self, results: &mut Self::Results); } /// A wrapper type implementing [`RngCore`] for some type implementing /// [`BlockRngCore`] with `u32` array buffer; i.e. this can be used to implement /// a full RNG from just a `generate` function. /// /// The `core` field may be accessed directly but the results buffer may not. /// PRNG implementations can simply use a type alias /// (`pub type MyRng = BlockRng;`) but might prefer to use a /// wrapper type (`pub struct MyRng(BlockRng);`); the latter must /// re-implement `RngCore` but hides the implementation details and allows /// extra functionality to be defined on the RNG /// (e.g. `impl MyRng { fn set_stream(...){...} }`). /// /// `BlockRng` has heavily optimized implementations of the [`RngCore`] methods /// reading values from the results buffer, as well as /// calling [`BlockRngCore::generate`] directly on the output array when /// [`fill_bytes`] / [`try_fill_bytes`] is called on a large array. These methods /// also handle the bookkeeping of when to generate a new batch of values. /// /// No whole generated `u32` values are thown away and all values are consumed /// in-order. [`next_u32`] simply takes the next available `u32` value. /// [`next_u64`] is implemented by combining two `u32` values, least /// significant first. [`fill_bytes`] and [`try_fill_bytes`] consume a whole /// number of `u32` values, converting each `u32` to a byte slice in /// little-endian order. If the requested byte length is not a multiple of 4, /// some bytes will be discarded. /// /// See also [`BlockRng64`] which uses `u64` array buffers. Currently there is /// no direct support for other buffer types. /// /// For easy initialization `BlockRng` also implements [`SeedableRng`]. /// /// [`next_u32`]: RngCore::next_u32 /// [`next_u64`]: RngCore::next_u64 /// [`fill_bytes`]: RngCore::fill_bytes /// [`try_fill_bytes`]: RngCore::try_fill_bytes #[derive(Clone)] #[cfg_attr(feature="serde1", derive(Serialize, Deserialize))] pub struct BlockRng { results: R::Results, index: usize, /// The *core* part of the RNG, implementing the `generate` function. pub core: R, } // Custom Debug implementation that does not expose the contents of `results`. impl fmt::Debug for BlockRng { fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result { fmt.debug_struct("BlockRng") .field("core", &self.core) .field("result_len", &self.results.as_ref().len()) .field("index", &self.index) .finish() } } impl BlockRng { /// Create a new `BlockRng` from an existing RNG implementing /// `BlockRngCore`. Results will be generated on first use. #[inline] pub fn new(core: R) -> BlockRng{ let results_empty = R::Results::default(); BlockRng { core, index: results_empty.as_ref().len(), results: results_empty, } } /// Get the index into the result buffer. /// /// If this is equal to or larger than the size of the result buffer then /// the buffer is "empty" and `generate()` must be called to produce new /// results. #[inline(always)] pub fn index(&self) -> usize { self.index } /// Reset the number of available results. /// This will force a new set of results to be generated on next use. #[inline] pub fn reset(&mut self) { self.index = self.results.as_ref().len(); } /// Generate a new set of results immediately, setting the index to the /// given value. #[inline] pub fn generate_and_set(&mut self, index: usize) { assert!(index < self.results.as_ref().len()); self.core.generate(&mut self.results); self.index = index; } } impl> RngCore for BlockRng where ::Results: AsRef<[u32]> + AsMut<[u32]> { #[inline] fn next_u32(&mut self) -> u32 { if self.index >= self.results.as_ref().len() { self.generate_and_set(0); } let value = self.results.as_ref()[self.index]; self.index += 1; value } #[inline] fn next_u64(&mut self) -> u64 { let read_u64 = |results: &[u32], index| { if cfg!(any(target_endian = "little")) { // requires little-endian CPU #[allow(clippy::cast_ptr_alignment)] // false positive let ptr: *const u64 = results[index..=index+1].as_ptr() as *const u64; unsafe { ptr::read_unaligned(ptr) } } else { let x = u64::from(results[index]); let y = u64::from(results[index + 1]); (y << 32) | x } }; let len = self.results.as_ref().len(); let index = self.index; if index < len-1 { self.index += 2; // Read an u64 from the current index read_u64(self.results.as_ref(), index) } else if index >= len { self.generate_and_set(2); read_u64(self.results.as_ref(), 0) } else { let x = u64::from(self.results.as_ref()[len-1]); self.generate_and_set(1); let y = u64::from(self.results.as_ref()[0]); (y << 32) | x } } #[inline] fn fill_bytes(&mut self, dest: &mut [u8]) { let mut read_len = 0; while read_len < dest.len() { if self.index >= self.results.as_ref().len() { self.generate_and_set(0); } let (consumed_u32, filled_u8) = fill_via_u32_chunks(&self.results.as_ref()[self.index..], &mut dest[read_len..]); self.index += consumed_u32; read_len += filled_u8; } } #[inline(always)] fn try_fill_bytes(&mut self, dest: &mut [u8]) -> Result<(), Error> { self.fill_bytes(dest); Ok(()) } } impl SeedableRng for BlockRng { type Seed = R::Seed; #[inline(always)] fn from_seed(seed: Self::Seed) -> Self { Self::new(R::from_seed(seed)) } #[inline(always)] fn seed_from_u64(seed: u64) -> Self { Self::new(R::seed_from_u64(seed)) } #[inline(always)] fn from_rng(rng: S) -> Result { Ok(Self::new(R::from_rng(rng)?)) } } /// A wrapper type implementing [`RngCore`] for some type implementing /// [`BlockRngCore`] with `u64` array buffer; i.e. this can be used to implement /// a full RNG from just a `generate` function. /// /// This is similar to [`BlockRng`], but specialized for algorithms that operate /// on `u64` values. /// /// No whole generated `u64` values are thrown away and all values are consumed /// in-order. [`next_u64`] simply takes the next available `u64` value. /// [`next_u32`] is however a bit special: half of a `u64` is consumed, leaving /// the other half in the buffer. If the next function called is [`next_u32`] /// then the other half is then consumed, however both [`next_u64`] and /// [`fill_bytes`] discard the rest of any half-consumed `u64`s when called. /// /// [`fill_bytes`] and [`try_fill_bytes`] consume a whole number of `u64` /// values. If the requested length is not a multiple of 8, some bytes will be /// discarded. /// /// [`next_u32`]: RngCore::next_u32 /// [`next_u64`]: RngCore::next_u64 /// [`fill_bytes`]: RngCore::fill_bytes /// [`try_fill_bytes`]: RngCore::try_fill_bytes #[derive(Clone)] #[cfg_attr(feature="serde1", derive(Serialize, Deserialize))] pub struct BlockRng64 { results: R::Results, index: usize, half_used: bool, // true if only half of the previous result is used /// The *core* part of the RNG, implementing the `generate` function. pub core: R, } // Custom Debug implementation that does not expose the contents of `results`. impl fmt::Debug for BlockRng64 { fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result { fmt.debug_struct("BlockRng64") .field("core", &self.core) .field("result_len", &self.results.as_ref().len()) .field("index", &self.index) .field("half_used", &self.half_used) .finish() } } impl BlockRng64 { /// Create a new `BlockRng` from an existing RNG implementing /// `BlockRngCore`. Results will be generated on first use. #[inline] pub fn new(core: R) -> BlockRng64{ let results_empty = R::Results::default(); BlockRng64 { core, index: results_empty.as_ref().len(), half_used: false, results: results_empty, } } /// Get the index into the result buffer. /// /// If this is equal to or larger than the size of the result buffer then /// the buffer is "empty" and `generate()` must be called to produce new /// results. #[inline(always)] pub fn index(&self) -> usize { self.index } /// Reset the number of available results. /// This will force a new set of results to be generated on next use. #[inline] pub fn reset(&mut self) { self.index = self.results.as_ref().len(); self.half_used = false; } /// Generate a new set of results immediately, setting the index to the /// given value. #[inline] pub fn generate_and_set(&mut self, index: usize) { assert!(index < self.results.as_ref().len()); self.core.generate(&mut self.results); self.index = index; self.half_used = false; } } impl> RngCore for BlockRng64 where ::Results: AsRef<[u64]> + AsMut<[u64]> { #[inline] fn next_u32(&mut self) -> u32 { let mut index = self.index * 2 - self.half_used as usize; if index >= self.results.as_ref().len() * 2 { self.core.generate(&mut self.results); self.index = 0; // `self.half_used` is by definition `false` self.half_used = false; index = 0; } self.half_used = !self.half_used; self.index += self.half_used as usize; // Index as if this is a u32 slice. unsafe { let results = &*(self.results.as_ref() as *const [u64] as *const [u32]); if cfg!(target_endian = "little") { *results.get_unchecked(index) } else { *results.get_unchecked(index ^ 1) } } } #[inline] fn next_u64(&mut self) -> u64 { if self.index >= self.results.as_ref().len() { self.core.generate(&mut self.results); self.index = 0; } let value = self.results.as_ref()[self.index]; self.index += 1; self.half_used = false; value } #[inline] fn fill_bytes(&mut self, dest: &mut [u8]) { let mut read_len = 0; self.half_used = false; while read_len < dest.len() { if self.index as usize >= self.results.as_ref().len() { self.core.generate(&mut self.results); self.index = 0; } let (consumed_u64, filled_u8) = fill_via_u64_chunks(&self.results.as_ref()[self.index as usize..], &mut dest[read_len..]); self.index += consumed_u64; read_len += filled_u8; } } #[inline(always)] fn try_fill_bytes(&mut self, dest: &mut [u8]) -> Result<(), Error> { self.fill_bytes(dest); Ok(()) } } impl SeedableRng for BlockRng64 { type Seed = R::Seed; #[inline(always)] fn from_seed(seed: Self::Seed) -> Self { Self::new(R::from_seed(seed)) } #[inline(always)] fn seed_from_u64(seed: u64) -> Self { Self::new(R::seed_from_u64(seed)) } #[inline(always)] fn from_rng(rng: S) -> Result { Ok(Self::new(R::from_rng(rng)?)) } } impl CryptoRng for BlockRng {} rand_core-0.5.1/src/error.rs010064400017500001750000000133271353146424500141750ustar0000000000000000// Copyright 2018 Developers of the Rand project. // // Licensed under the Apache License, Version 2.0 or the MIT license // , at your // option. This file may not be copied, modified, or distributed // except according to those terms. //! Error types use core::fmt; use core::num::NonZeroU32; /// Error type of random number generators /// /// In order to be compatible with `std` and `no_std`, this type has two /// possible implementations: with `std` a boxed `Error` trait object is stored, /// while with `no_std` we merely store an error code. pub struct Error { #[cfg(feature="std")] inner: Box, #[cfg(not(feature="std"))] code: NonZeroU32, } impl Error { /// Construct from any type supporting `std::error::Error` /// /// Available only when configured with `std`. /// /// See also `From`, which is available with and without `std`. #[cfg(feature="std")] #[inline] pub fn new(err: E) -> Self where E: Into> { Error { inner: err.into() } } /// Reference the inner error (`std` only) /// /// When configured with `std`, this is a trivial operation and never /// panics. Without `std`, this method is simply unavailable. #[cfg(feature="std")] #[inline] pub fn inner(&self) -> &(dyn std::error::Error + Send + Sync + 'static) { &*self.inner } /// Unwrap the inner error (`std` only) /// /// When configured with `std`, this is a trivial operation and never /// panics. Without `std`, this method is simply unavailable. #[cfg(feature="std")] #[inline] pub fn take_inner(self) -> Box { self.inner } /// 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 `Diplay` implementation. #[inline] pub fn raw_os_error(&self) -> Option { #[cfg(feature="std")] { if let Some(e) = self.inner.downcast_ref::() { return e.raw_os_error(); } } match self.code() { Some(code) if u32::from(code) < Self::INTERNAL_START => Some(u32::from(code) as i32), _ => None, } } /// Retrieve the error code, if any. /// /// If this `Error` was constructed via `From`, then this method /// will return this `NonZeroU32` code (for `no_std` this is always the /// case). Otherwise, this method will return `None`. #[inline] pub fn code(&self) -> Option { #[cfg(feature="std")] { self.inner.downcast_ref::().map(|c| c.0) } #[cfg(not(feature="std"))] { Some(self.code) } } } impl fmt::Debug for Error { fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { #[cfg(feature="std")] { write!(f, "Error {{ inner: {:?} }}", self.inner) } #[cfg(all(feature="getrandom", not(feature="std")))] { getrandom::Error::from(self.code).fmt(f) } #[cfg(not(feature="getrandom"))] { write!(f, "Error {{ code: {} }}", self.code) } } } impl fmt::Display for Error { fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { #[cfg(feature="std")] { write!(f, "{}", self.inner) } #[cfg(all(feature="getrandom", not(feature="std")))] { getrandom::Error::from(self.code).fmt(f) } #[cfg(not(feature="getrandom"))] { write!(f, "error code {}", self.code) } } } impl From for Error { #[inline] fn from(code: NonZeroU32) -> Self { #[cfg(feature="std")] { Error { inner: Box::new(ErrorCode(code)) } } #[cfg(not(feature="std"))] { Error { code } } } } #[cfg(feature="getrandom")] impl From for Error { #[inline] fn from(error: getrandom::Error) -> Self { #[cfg(feature="std")] { Error { inner: Box::new(error) } } #[cfg(not(feature="std"))] { Error { code: error.code() } } } } #[cfg(feature="std")] impl std::error::Error for Error { #[inline] fn source(&self) -> Option<&(dyn std::error::Error + 'static)> { self.inner.source() } } #[cfg(feature="std")] impl From for std::io::Error { #[inline] fn from(error: Error) -> Self { if let Some(code) = error.raw_os_error() { std::io::Error::from_raw_os_error(code) } else { std::io::Error::new(std::io::ErrorKind::Other, error) } } } #[cfg(feature="std")] #[derive(Debug, Copy, Clone)] struct ErrorCode(NonZeroU32); #[cfg(feature="std")] impl fmt::Display for ErrorCode { fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { write!(f, "error code {}", self.0) } } #[cfg(feature="std")] impl std::error::Error for ErrorCode {} rand_core-0.5.1/src/impls.rs010064400017500001750000000126141352324657500141730ustar0000000000000000// Copyright 2018 Developers of the Rand project. // // Licensed under the Apache License, Version 2.0 or the MIT license // , at your // option. This file may not be copied, modified, or distributed // except according to those terms. //! Helper functions for implementing `RngCore` functions. //! //! For cross-platform reproducibility, these functions all use Little Endian: //! least-significant part first. For example, `next_u64_via_u32` takes `u32` //! values `x, y`, then outputs `(y << 32) | x`. To implement `next_u32` //! from `next_u64` in little-endian order, one should use `next_u64() as u32`. //! //! Byte-swapping (like the std `to_le` functions) is only needed to convert //! to/from byte sequences, and since its purpose is reproducibility, //! non-reproducible sources (e.g. `OsRng`) need not bother with it. use core::ptr::copy_nonoverlapping; use core::slice; use core::cmp::min; use core::mem::size_of; use crate::RngCore; /// Implement `next_u64` via `next_u32`, little-endian order. pub fn next_u64_via_u32(rng: &mut R) -> u64 { // Use LE; we explicitly generate one value before the next. let x = u64::from(rng.next_u32()); let y = u64::from(rng.next_u32()); (y << 32) | x } /// Implement `fill_bytes` via `next_u64` and `next_u32`, little-endian order. /// /// The fastest way to fill a slice is usually to work as long as possible with /// integers. That is why this method mostly uses `next_u64`, and only when /// there are 4 or less bytes remaining at the end of the slice it uses /// `next_u32` once. pub fn fill_bytes_via_next(rng: &mut R, dest: &mut [u8]) { let mut left = dest; while left.len() >= 8 { let (l, r) = {left}.split_at_mut(8); left = r; let chunk: [u8; 8] = rng.next_u64().to_le_bytes(); l.copy_from_slice(&chunk); } let n = left.len(); if n > 4 { let chunk: [u8; 8] = rng.next_u64().to_le_bytes(); left.copy_from_slice(&chunk[..n]); } else if n > 0 { let chunk: [u8; 4] = rng.next_u32().to_le_bytes(); left.copy_from_slice(&chunk[..n]); } } macro_rules! impl_uint_from_fill { ($rng:expr, $ty:ty, $N:expr) => ({ debug_assert!($N == size_of::<$ty>()); let mut int: $ty = 0; unsafe { let ptr = &mut int as *mut $ty as *mut u8; let slice = slice::from_raw_parts_mut(ptr, $N); $rng.fill_bytes(slice); } int }); } macro_rules! fill_via_chunks { ($src:expr, $dst:expr, $ty:ty, $size:expr) => ({ let chunk_size_u8 = min($src.len() * $size, $dst.len()); let chunk_size = (chunk_size_u8 + $size - 1) / $size; if cfg!(target_endian="little") { unsafe { copy_nonoverlapping( $src.as_ptr() as *const u8, $dst.as_mut_ptr(), chunk_size_u8); } } else { for (&n, chunk) in $src.iter().zip($dst.chunks_mut($size)) { let tmp = n.to_le(); let src_ptr = &tmp as *const $ty as *const u8; unsafe { copy_nonoverlapping(src_ptr, chunk.as_mut_ptr(), chunk.len()); } } } (chunk_size, chunk_size_u8) }); } /// Implement `fill_bytes` by reading chunks from the output buffer of a block /// based RNG. /// /// The return values are `(consumed_u32, filled_u8)`. /// /// `filled_u8` is the number of filled bytes in `dest`, which may be less than /// the length of `dest`. /// `consumed_u32` is the number of words consumed from `src`, which is the same /// as `filled_u8 / 4` rounded up. /// /// # Example /// (from `IsaacRng`) /// /// ```ignore /// fn fill_bytes(&mut self, dest: &mut [u8]) { /// let mut read_len = 0; /// while read_len < dest.len() { /// if self.index >= self.rsl.len() { /// self.isaac(); /// } /// /// let (consumed_u32, filled_u8) = /// impls::fill_via_u32_chunks(&mut self.rsl[self.index..], /// &mut dest[read_len..]); /// /// self.index += consumed_u32; /// read_len += filled_u8; /// } /// } /// ``` pub fn fill_via_u32_chunks(src: &[u32], dest: &mut [u8]) -> (usize, usize) { fill_via_chunks!(src, dest, u32, 4) } /// Implement `fill_bytes` by reading chunks from the output buffer of a block /// based RNG. /// /// The return values are `(consumed_u64, filled_u8)`. /// `filled_u8` is the number of filled bytes in `dest`, which may be less than /// the length of `dest`. /// `consumed_u64` is the number of words consumed from `src`, which is the same /// as `filled_u8 / 8` rounded up. /// /// See `fill_via_u32_chunks` for an example. pub fn fill_via_u64_chunks(src: &[u64], dest: &mut [u8]) -> (usize, usize) { fill_via_chunks!(src, dest, u64, 8) } /// Implement `next_u32` via `fill_bytes`, little-endian order. pub fn next_u32_via_fill(rng: &mut R) -> u32 { impl_uint_from_fill!(rng, u32, 4) } /// Implement `next_u64` via `fill_bytes`, little-endian order. pub fn next_u64_via_fill(rng: &mut R) -> u64 { impl_uint_from_fill!(rng, u64, 8) } // TODO: implement tests for the above rand_core-0.5.1/src/le.rs010064400017500001750000000037331351702042700134360ustar0000000000000000// Copyright 2018 Developers of the Rand project. // // Licensed under the Apache License, Version 2.0 or the MIT license // , at your // option. This file may not be copied, modified, or distributed // except according to those terms. //! Little-Endian utilities //! //! Little-Endian order has been chosen for internal usage; this makes some //! useful functions available. use core::ptr; macro_rules! read_slice { ($src:expr, $dst:expr, $size:expr, $which:ident) => {{ assert_eq!($src.len(), $size * $dst.len()); unsafe { ptr::copy_nonoverlapping( $src.as_ptr(), $dst.as_mut_ptr() as *mut u8, $src.len()); } for v in $dst.iter_mut() { *v = v.$which(); } }}; } /// Reads unsigned 32 bit integers from `src` into `dst`. /// Borrowed from the `byteorder` crate. #[inline] pub fn read_u32_into(src: &[u8], dst: &mut [u32]) { read_slice!(src, dst, 4, to_le); } /// Reads unsigned 64 bit integers from `src` into `dst`. /// Borrowed from the `byteorder` crate. #[inline] pub fn read_u64_into(src: &[u8], dst: &mut [u64]) { read_slice!(src, dst, 8, to_le); } #[test] fn test_read() { let bytes = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16]; let mut buf = [0u32; 4]; read_u32_into(&bytes, &mut buf); assert_eq!(buf[0], 0x04030201); assert_eq!(buf[3], 0x100F0E0D); let mut buf = [0u32; 3]; read_u32_into(&bytes[1..13], &mut buf); // unaligned assert_eq!(buf[0], 0x05040302); assert_eq!(buf[2], 0x0D0C0B0A); let mut buf = [0u64; 2]; read_u64_into(&bytes, &mut buf); assert_eq!(buf[0], 0x0807060504030201); assert_eq!(buf[1], 0x100F0E0D0C0B0A09); let mut buf = [0u64; 1]; read_u64_into(&bytes[7..15], &mut buf); // unaligned assert_eq!(buf[0], 0x0F0E0D0C0B0A0908); } rand_core-0.5.1/src/lib.rs010064400017500001750000000456601353146424500136170ustar0000000000000000// Copyright 2018 Developers of the Rand project. // Copyright 2017-2018 The Rust Project Developers. // // Licensed under the Apache License, Version 2.0 or the MIT license // , at your // option. This file may not be copied, modified, or distributed // except according to those terms. //! Random number generation traits //! //! This crate is mainly of interest to crates publishing implementations of //! [`RngCore`]. Other users are encouraged to use the [`rand`] crate instead //! which re-exports the main traits and error types. //! //! [`RngCore`] is the core trait implemented by algorithmic pseudo-random number //! generators and external random-number sources. //! //! [`SeedableRng`] is an extension trait for construction from fixed seeds and //! other random number generators. //! //! [`Error`] is provided for error-handling. It is safe to use in `no_std` //! environments. //! //! The [`impls`] and [`le`] sub-modules include a few small functions to assist //! implementation of [`RngCore`]. //! //! [`rand`]: https://docs.rs/rand #![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/")] #![deny(missing_docs)] #![deny(missing_debug_implementations)] #![doc(test(attr(allow(unused_variables), deny(warnings))))] #![allow(clippy::unreadable_literal)] #![cfg_attr(not(feature="std"), no_std)] use core::default::Default; use core::convert::AsMut; use core::ptr::copy_nonoverlapping; #[cfg(all(feature="alloc", not(feature="std")))] extern crate alloc; #[cfg(all(feature="alloc", not(feature="std")))] use alloc::boxed::Box; pub use error::Error; #[cfg(feature="getrandom")] pub use os::OsRng; mod error; pub mod block; pub mod impls; pub mod le; #[cfg(feature="getrandom")] mod os; /// The core of a random number generator. /// /// This trait encapsulates the low-level functionality common to all /// generators, and is the "back end", to be implemented by generators. /// End users should normally use the `Rng` trait from the [`rand`] crate, /// which is automatically implemented for every type implementing `RngCore`. /// /// Three different methods for generating random data are provided since the /// optimal implementation of each is dependent on the type of generator. There /// is no required relationship between the output of each; e.g. many /// implementations of [`fill_bytes`] consume a whole number of `u32` or `u64` /// values and drop any remaining unused bytes. /// /// The [`try_fill_bytes`] method is a variant of [`fill_bytes`] allowing error /// handling; it is not deemed sufficiently useful to add equivalents for /// [`next_u32`] or [`next_u64`] since the latter methods are almost always used /// with algorithmic generators (PRNGs), which are normally infallible. /// /// Algorithmic generators implementing [`SeedableRng`] should normally have /// *portable, reproducible* output, i.e. fix Endianness when converting values /// to avoid platform differences, and avoid making any changes which affect /// output (except by communicating that the release has breaking changes). /// /// Typically implementators will implement only one of the methods available /// in this trait directly, then use the helper functions from the /// [`impls`] module to implement the other methods. /// /// It is recommended that implementations also implement: /// /// - `Debug` with a custom implementation which *does not* print any internal /// state (at least, [`CryptoRng`]s should not risk leaking state through /// `Debug`). /// - `Serialize` and `Deserialize` (from Serde), preferably making Serde /// support optional at the crate level in PRNG libs. /// - `Clone`, if possible. /// - *never* implement `Copy` (accidental copies may cause repeated values). /// - *do not* implement `Default` for pseudorandom generators, but instead /// implement [`SeedableRng`], to guide users towards proper seeding. /// External / hardware RNGs can choose to implement `Default`. /// - `Eq` and `PartialEq` could be implemented, but are probably not useful. /// /// # Example /// /// A simple example, obviously not generating very *random* output: /// /// ``` /// #![allow(dead_code)] /// use rand_core::{RngCore, Error, impls}; /// /// struct CountingRng(u64); /// /// impl RngCore for CountingRng { /// fn next_u32(&mut self) -> u32 { /// self.next_u64() as u32 /// } /// /// fn next_u64(&mut self) -> u64 { /// self.0 += 1; /// self.0 /// } /// /// fn fill_bytes(&mut self, dest: &mut [u8]) { /// impls::fill_bytes_via_next(self, dest) /// } /// /// fn try_fill_bytes(&mut self, dest: &mut [u8]) -> Result<(), Error> { /// Ok(self.fill_bytes(dest)) /// } /// } /// ``` /// /// [`rand`]: https://docs.rs/rand /// [`try_fill_bytes`]: RngCore::try_fill_bytes /// [`fill_bytes`]: RngCore::fill_bytes /// [`next_u32`]: RngCore::next_u32 /// [`next_u64`]: RngCore::next_u64 pub trait RngCore { /// Return the next random `u32`. /// /// RNGs must implement at least one method from this trait directly. In /// the case this method is not implemented directly, it can be implemented /// using `self.next_u64() as u32` or via /// [`fill_bytes`](impls::next_u32_via_fill). fn next_u32(&mut self) -> u32; /// Return the next random `u64`. /// /// RNGs must implement at least one method from this trait directly. In /// the case this method is not implemented directly, it can be implemented /// via [`next_u32`](impls::next_u64_via_u32) or via /// [`fill_bytes`](impls::next_u64_via_fill). fn next_u64(&mut self) -> u64; /// Fill `dest` with random data. /// /// RNGs must implement at least one method from this trait directly. In /// the case this method is not implemented directly, it can be implemented /// via [`next_u*`](impls::fill_bytes_via_next) or /// via [`try_fill_bytes`](RngCore::try_fill_bytes); if this generator can /// fail the implementation must choose how best to handle errors here /// (e.g. panic with a descriptive message or log a warning and retry a few /// times). /// /// This method should guarantee that `dest` is entirely filled /// with new data, and may panic if this is impossible /// (e.g. reading past the end of a file that is being used as the /// source of randomness). fn fill_bytes(&mut self, dest: &mut [u8]); /// Fill `dest` entirely with random data. /// /// This is the only method which allows an RNG to report errors while /// generating random data thus making this the primary method implemented /// by external (true) RNGs (e.g. `OsRng`) which can fail. It may be used /// directly to generate keys and to seed (infallible) PRNGs. /// /// Other than error handling, this method is identical to [`fill_bytes`]; /// thus this may be implemented using `Ok(self.fill_bytes(dest))` or /// `fill_bytes` may be implemented with /// `self.try_fill_bytes(dest).unwrap()` or more specific error handling. /// /// [`fill_bytes`]: RngCore::fill_bytes fn try_fill_bytes(&mut self, dest: &mut [u8]) -> Result<(), Error>; } /// A marker trait used to indicate that an [`RngCore`] or [`BlockRngCore`] /// implementation is supposed to be cryptographically secure. /// /// *Cryptographically secure generators*, also known as *CSPRNGs*, should /// satisfy an additional properties over other generators: given the first /// *k* bits of an algorithm's output /// sequence, it should not be possible using polynomial-time algorithms to /// predict the next bit with probability significantly greater than 50%. /// /// Some generators may satisfy an additional property, however this is not /// required by this trait: if the CSPRNG's state is revealed, it should not be /// computationally-feasible to reconstruct output prior to this. Some other /// generators allow backwards-computation and are consided *reversible*. /// /// Note that this trait is provided for guidance only and cannot guarantee /// suitability for cryptographic applications. In general it should only be /// implemented for well-reviewed code implementing well-regarded algorithms. /// /// Note also that use of a `CryptoRng` does not protect against other /// weaknesses such as seeding from a weak entropy source or leaking state. /// /// [`BlockRngCore`]: block::BlockRngCore pub trait CryptoRng {} /// A random number generator that can be explicitly seeded. /// /// This trait encapsulates the low-level functionality common to all /// pseudo-random number generators (PRNGs, or algorithmic generators). /// /// [`rand`]: https://docs.rs/rand pub trait SeedableRng: Sized { /// Seed type, which is restricted to types mutably-dereferencable as `u8` /// arrays (we recommend `[u8; N]` for some `N`). /// /// It is recommended to seed PRNGs with a seed of at least circa 100 bits, /// which means an array of `[u8; 12]` or greater to avoid picking RNGs with /// partially overlapping periods. /// /// For cryptographic RNG's a seed of 256 bits is recommended, `[u8; 32]`. /// /// /// # Implementing `SeedableRng` for RNGs with large seeds /// /// Note that the required traits `core::default::Default` and /// `core::convert::AsMut` are not implemented for large arrays /// `[u8; N]` with `N` > 32. To be able to implement the traits required by /// `SeedableRng` for RNGs with such large seeds, the newtype pattern can be /// used: /// /// ``` /// use rand_core::SeedableRng; /// /// const N: usize = 64; /// pub struct MyRngSeed(pub [u8; N]); /// pub struct MyRng(MyRngSeed); /// /// impl Default for MyRngSeed { /// fn default() -> MyRngSeed { /// MyRngSeed([0; N]) /// } /// } /// /// impl AsMut<[u8]> for MyRngSeed { /// fn as_mut(&mut self) -> &mut [u8] { /// &mut self.0 /// } /// } /// /// impl SeedableRng for MyRng { /// type Seed = MyRngSeed; /// /// fn from_seed(seed: MyRngSeed) -> MyRng { /// MyRng(seed) /// } /// } /// ``` type Seed: Sized + Default + AsMut<[u8]>; /// Create a new PRNG using the given seed. /// /// PRNG implementations are allowed to assume that bits in the seed are /// well distributed. That means usually that the number of one and zero /// bits are roughly equal, and values like 0, 1 and (size - 1) are unlikely. /// Note that many non-cryptographic PRNGs will show poor quality output /// if this is not adhered to. If you wish to seed from simple numbers, use /// `seed_from_u64` instead. /// /// All PRNG implementations should be reproducible unless otherwise noted: /// given a fixed `seed`, the same sequence of output should be produced /// on all runs, library versions and architectures (e.g. check endianness). /// Any "value-breaking" changes to the generator should require bumping at /// least the minor version and documentation of the change. /// /// It is not required that this function yield the same state as a /// reference implementation of the PRNG given equivalent seed; if necessary /// another constructor replicating behaviour from a reference /// implementation can be added. /// /// PRNG implementations should make sure `from_seed` never panics. In the /// case that some special values (like an all zero seed) are not viable /// seeds it is preferable to map these to alternative constant value(s), /// for example `0xBAD5EEDu32` or `0x0DDB1A5E5BAD5EEDu64` ("odd biases? bad /// seed"). This is assuming only a small number of values must be rejected. fn from_seed(seed: Self::Seed) -> Self; /// Create a new PRNG using a `u64` seed. /// /// This is a convenience-wrapper around `from_seed` to allow construction /// of any `SeedableRng` from a simple `u64` value. It is designed such that /// low Hamming Weight numbers like 0 and 1 can be used and should still /// result in good, independent seeds to the PRNG which is returned. /// /// This **is not suitable for cryptography**, as should be clear given that /// the input size is only 64 bits. /// /// Implementations for PRNGs *may* provide their own implementations of /// this function, but the default implementation should be good enough for /// all purposes. *Changing* the implementation of this function should be /// considered a value-breaking change. fn seed_from_u64(mut state: u64) -> Self { // We use PCG32 to generate a u32 sequence, and copy to the seed const MUL: u64 = 6364136223846793005; const INC: u64 = 11634580027462260723; let mut seed = Self::Seed::default(); for chunk in seed.as_mut().chunks_mut(4) { // We advance the state first (to get away from the input value, // in case it has low Hamming Weight). state = state.wrapping_mul(MUL).wrapping_add(INC); // Use PCG output function with to_le to generate x: let xorshifted = (((state >> 18) ^ state) >> 27) as u32; let rot = (state >> 59) as u32; let x = xorshifted.rotate_right(rot).to_le(); unsafe { let p = &x as *const u32 as *const u8; copy_nonoverlapping(p, chunk.as_mut_ptr(), chunk.len()); } } Self::from_seed(seed) } /// Create a new PRNG seeded from another `Rng`. /// /// This may be useful when needing to rapidly seed many PRNGs from a master /// PRNG, and to allow forking of PRNGs. It may be considered deterministic. /// /// The master PRNG should be at least as high quality as the child PRNGs. /// When seeding non-cryptographic child PRNGs, we recommend using a /// different algorithm for the master PRNG (ideally a CSPRNG) to avoid /// correlations between the child PRNGs. If this is not possible (e.g. /// forking using small non-crypto PRNGs) ensure that your PRNG has a good /// mixing function on the output or consider use of a hash function with /// `from_seed`. /// /// Note that seeding `XorShiftRng` from another `XorShiftRng` provides an /// extreme example of what can go wrong: the new PRNG will be a clone /// of the parent. /// /// PRNG implementations are allowed to assume that a good RNG is provided /// for seeding, and that it is cryptographically secure when appropriate. /// As of `rand` 0.7 / `rand_core` 0.5, implementations overriding this /// method should ensure the implementation satisfies reproducibility /// (in prior versions this was not required). /// /// [`rand`]: https://docs.rs/rand /// [`rand_os`]: https://docs.rs/rand_os fn from_rng(mut rng: R) -> Result { let mut seed = Self::Seed::default(); rng.try_fill_bytes(seed.as_mut())?; Ok(Self::from_seed(seed)) } /// Creates a new instance of the RNG seeded via [`getrandom`]. /// /// This method is the recommended way to construct non-deterministic PRNGs /// since it is convenient and secure. /// /// In case the overhead of using [`getrandom`] to seed *many* PRNGs is an /// issue, one may prefer to seed from a local PRNG, e.g. /// `from_rng(thread_rng()).unwrap()`. /// /// # Panics /// /// If [`getrandom`] is unable to provide secure entropy this method will panic. /// /// [`getrandom`]: https://docs.rs/getrandom #[cfg(feature="getrandom")] fn from_entropy() -> Self { let mut seed = Self::Seed::default(); if let Err(err) = getrandom::getrandom(seed.as_mut()) { panic!("from_entropy failed: {}", err); } Self::from_seed(seed) } } // Implement `RngCore` for references to an `RngCore`. // Force inlining all functions, so that it is up to the `RngCore` // implementation and the optimizer to decide on inlining. impl<'a, R: RngCore + ?Sized> RngCore for &'a mut R { #[inline(always)] fn next_u32(&mut self) -> u32 { (**self).next_u32() } #[inline(always)] fn next_u64(&mut self) -> u64 { (**self).next_u64() } #[inline(always)] fn fill_bytes(&mut self, dest: &mut [u8]) { (**self).fill_bytes(dest) } #[inline(always)] fn try_fill_bytes(&mut self, dest: &mut [u8]) -> Result<(), Error> { (**self).try_fill_bytes(dest) } } // Implement `RngCore` for boxed references to an `RngCore`. // Force inlining all functions, so that it is up to the `RngCore` // implementation and the optimizer to decide on inlining. #[cfg(feature="alloc")] impl RngCore for Box { #[inline(always)] fn next_u32(&mut self) -> u32 { (**self).next_u32() } #[inline(always)] fn next_u64(&mut self) -> u64 { (**self).next_u64() } #[inline(always)] fn fill_bytes(&mut self, dest: &mut [u8]) { (**self).fill_bytes(dest) } #[inline(always)] fn try_fill_bytes(&mut self, dest: &mut [u8]) -> Result<(), Error> { (**self).try_fill_bytes(dest) } } #[cfg(feature="std")] impl std::io::Read for dyn RngCore { fn read(&mut self, buf: &mut [u8]) -> Result { self.try_fill_bytes(buf)?; Ok(buf.len()) } } // Implement `CryptoRng` for references to an `CryptoRng`. impl<'a, R: CryptoRng + ?Sized> CryptoRng for &'a mut R {} // Implement `CryptoRng` for boxed references to an `CryptoRng`. #[cfg(feature="alloc")] impl CryptoRng for Box {} #[cfg(test)] mod test { use super::*; #[test] fn test_seed_from_u64() { struct SeedableNum(u64); impl SeedableRng for SeedableNum { type Seed = [u8; 8]; fn from_seed(seed: Self::Seed) -> Self { let mut x = [0u64; 1]; le::read_u64_into(&seed, &mut x); SeedableNum(x[0]) } } const N: usize = 8; const SEEDS: [u64; N] = [0u64, 1, 2, 3, 4, 8, 16, -1i64 as u64]; let mut results = [0u64; N]; for (i, seed) in SEEDS.iter().enumerate() { let SeedableNum(x) = SeedableNum::seed_from_u64(*seed); results[i] = x; } for (i1, r1) in results.iter().enumerate() { let weight = r1.count_ones(); // This is the binomial distribution B(64, 0.5), so chance of // weight < 20 is binocdf(19, 64, 0.5) = 7.8e-4, and same for // weight > 44. assert!(weight >= 20 && weight <= 44); for (i2, r2) in results.iter().enumerate() { if i1 == i2 { continue; } let diff_weight = (r1 ^ r2).count_ones(); assert!(diff_weight >= 20); } } // value-breakage test: assert_eq!(results[0], 5029875928683246316); } } rand_core-0.5.1/src/os.rs010064400017500001750000000047731353146424500134720ustar0000000000000000// Copyright 2019 Developers of the Rand project. // // Licensed under the Apache License, Version 2.0 or the MIT license // , 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. // Note: keep this code in sync with the rand_os crate! use getrandom::getrandom; use crate::{CryptoRng, RngCore, Error, impls}; /// A random number generator that retrieves randomness from from the /// operating system. /// /// This is a zero-sized struct. It can be freely constructed with `OsRng`. /// /// The implementation is provided by the [getrandom] crate. Refer to /// [getrandom] documentation for details. /// /// This struct is only available when specifying the crate feature `getrandom` /// or `std`. When using the `rand` lib, it is also available as `rand::rngs::OsRng`. /// /// # Blocking and error handling /// /// It is possible that when used during early boot the first call to `OsRng` /// will block until the system's RNG is initialised. It is also possible /// (though highly unlikely) for `OsRng` to fail on some platforms, most /// likely due to system mis-configuration. /// /// After the first successful call, it is highly unlikely that failures or /// significant delays will occur (although performance should be expected to /// be much slower than a user-space PRNG). /// /// # Usage example /// ``` /// use rand_core::{RngCore, OsRng}; /// /// let mut key = [0u8; 16]; /// OsRng.fill_bytes(&mut key); /// let random_u64 = OsRng.next_u64(); /// ``` /// /// [getrandom]: https://crates.io/crates/getrandom #[derive(Clone, Copy, Debug, Default)] pub struct OsRng; impl CryptoRng for OsRng {} impl RngCore for OsRng { fn next_u32(&mut self) -> u32 { impls::next_u32_via_fill(self) } fn next_u64(&mut self) -> u64 { impls::next_u64_via_fill(self) } fn fill_bytes(&mut self, dest: &mut [u8]) { if let Err(e) = self.try_fill_bytes(dest) { panic!("Error: {}", e); } } fn try_fill_bytes(&mut self, dest: &mut [u8]) -> Result<(), Error> { getrandom(dest)?; Ok(()) } } #[test] fn test_os_rng() { let x = OsRng.next_u64(); let y = OsRng.next_u64(); assert!(x != 0); assert!(x != y); } #[test] fn test_construction() { let mut rng = OsRng::default(); assert!(rng.next_u64() != 0); } rand_core-0.5.1/.cargo_vcs_info.json0000644000000001120000000000000130240ustar00{ "git": { "sha1": "d877ed528248b52d947e0484364a4e1ae59ca502" } }