From 8350ac6afb2d678b74581000a6aafe1994b72231 Mon Sep 17 00:00:00 2001 From: Daniel Mueller Date: Wed, 16 Jan 2019 17:26:30 -0800 Subject: Update nitrokey crate to 0.3.3 This change updates the nitrokey crate to version 0.3.3. Along with that change we update rand to 0.6.4 because rand 0.6.1 does not yet contain a publicly accessible rand_os. Note that we no longer require all crates in rand's workspace, but only rand_os and rand_core, which is a significant reduction in the number of lines of code compiled. Import subrepo nitrokey/:nitrokey at 7cf747d56ddc0b7eeedc3caf36dcc909907a171c Import subrepo rand/:rand at 4336232dda03323634b10ec72ddf27914aebc3a2 --- rand/rand_xoshiro/src/xoshiro128plus.rs | 114 ++++++++++++++++++++++++++++++++ 1 file changed, 114 insertions(+) create mode 100644 rand/rand_xoshiro/src/xoshiro128plus.rs (limited to 'rand/rand_xoshiro/src/xoshiro128plus.rs') diff --git a/rand/rand_xoshiro/src/xoshiro128plus.rs b/rand/rand_xoshiro/src/xoshiro128plus.rs new file mode 100644 index 0000000..b0c7cc7 --- /dev/null +++ b/rand/rand_xoshiro/src/xoshiro128plus.rs @@ -0,0 +1,114 @@ +// 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. + +use rand_core::impls::{next_u64_via_u32, fill_bytes_via_next}; +use rand_core::le::read_u32_into; +use rand_core::{SeedableRng, RngCore, Error}; + +/// A xoshiro128+ random number generator. +/// +/// The xoshiro128+ algorithm is not suitable for cryptographic purposes, but +/// is very fast and has good statistical properties, besides a low linear +/// complexity in the lowest bits. +/// +/// The algorithm used here is translated from [the `xoshiro128starstar.c` +/// reference source code](http://xoshiro.di.unimi.it/xoshiro128starstar.c) by +/// David Blackman and Sebastiano Vigna. +#[derive(Debug, Clone)] +pub struct Xoshiro128Plus { + s: [u32; 4], +} + +impl Xoshiro128Plus { + /// Jump forward, equivalently to 2^64 calls to `next_u32()`. + /// + /// This can be used to generate 2^64 non-overlapping subsequences for + /// parallel computations. + /// + /// ``` + /// # extern crate rand; + /// # extern crate rand_xoshiro; + /// # fn main() { + /// use rand::SeedableRng; + /// use rand_xoshiro::Xoroshiro128StarStar; + /// + /// let rng1 = Xoroshiro128StarStar::seed_from_u64(0); + /// let mut rng2 = rng1.clone(); + /// rng2.jump(); + /// let mut rng3 = rng2.clone(); + /// rng3.jump(); + /// # } + /// ``` + pub fn jump(&mut self) { + impl_jump!(u32, self, [0x8764000b, 0xf542d2d3, 0x6fa035c3, 0x77f2db5b]); + } +} + +impl SeedableRng for Xoshiro128Plus { + type Seed = [u8; 16]; + + /// Create a new `Xoshiro128Plus`. If `seed` is entirely 0, it will be + /// mapped to a different seed. + #[inline] + fn from_seed(seed: [u8; 16]) -> Xoshiro128Plus { + deal_with_zero_seed!(seed, Self); + let mut state = [0; 4]; + read_u32_into(&seed, &mut state); + Xoshiro128Plus { s: state } + } + + /// Seed a `Xoshiro128Plus` from a `u64` using `SplitMix64`. + fn seed_from_u64(seed: u64) -> Xoshiro128Plus { + from_splitmix!(seed) + } +} + +impl RngCore for Xoshiro128Plus { + #[inline] + fn next_u32(&mut self) -> u32 { + let result_plus = self.s[0].wrapping_add(self.s[3]); + impl_xoshiro_u32!(self); + result_plus + } + + #[inline] + fn next_u64(&mut self) -> u64 { + next_u64_via_u32(self) + } + + #[inline] + fn fill_bytes(&mut self, dest: &mut [u8]) { + fill_bytes_via_next(self, dest); + } + + #[inline] + fn try_fill_bytes(&mut self, dest: &mut [u8]) -> Result<(), Error> { + self.fill_bytes(dest); + Ok(()) + } +} + +#[cfg(test)] +mod tests { + use super::*; + + #[test] + fn reference() { + let mut rng = Xoshiro128Plus::from_seed( + [1, 0, 0, 0, 2, 0, 0, 0, 3, 0, 0, 0, 4, 0, 0, 0]); + // These values were produced with the reference implementation: + // http://xoshiro.di.unimi.it/xoshiro128plus.c + let expected = [ + 5, 12295, 25178119, 27286542, 39879690, 1140358681, 3276312097, + 4110231701, 399823256, 2144435200, + ]; + for &e in &expected { + assert_eq!(rng.next_u32(), e); + } + } +} -- cgit v1.2.1