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authorDaniel Mueller <deso@posteo.net>2019-01-16 17:26:30 -0800
committerDaniel Mueller <deso@posteo.net>2019-01-16 17:26:30 -0800
commit8350ac6afb2d678b74581000a6aafe1994b72231 (patch)
tree2330da01a806921b3849c9e64d2b9f506495e2c0 /rand/rand_xoshiro/src/splitmix64.rs
parentd6652b913b33e432a748187f9f5623cec1e9926e (diff)
downloadnitrocli-8350ac6afb2d678b74581000a6aafe1994b72231.tar.gz
nitrocli-8350ac6afb2d678b74581000a6aafe1994b72231.tar.bz2
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
Diffstat (limited to 'rand/rand_xoshiro/src/splitmix64.rs')
-rw-r--r--rand/rand_xoshiro/src/splitmix64.rs150
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diff --git a/rand/rand_xoshiro/src/splitmix64.rs b/rand/rand_xoshiro/src/splitmix64.rs
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+++ b/rand/rand_xoshiro/src/splitmix64.rs
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+// 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 byteorder::{ByteOrder, LittleEndian};
+use rand_core::le::read_u64_into;
+use rand_core::impls::fill_bytes_via_next;
+use rand_core::{RngCore, SeedableRng, Error};
+
+/// A splitmix64 random number generator.
+///
+/// The splitmix algorithm is not suitable for cryptographic purposes, but is
+/// very fast and has a 64 bit state.
+///
+/// The algorithm used here is translated from [the `splitmix64.c`
+/// reference source code](http://xoshiro.di.unimi.it/splitmix64.c) by
+/// Sebastiano Vigna. For `next_u32`, a more efficient mixing function taken
+/// from [`dsiutils`](http://dsiutils.di.unimi.it/) is used.
+#[allow(missing_copy_implementations)]
+#[derive(Debug, Clone)]
+pub struct SplitMix64 {
+ x: u64,
+}
+
+const PHI: u64 = 0x9e3779b97f4a7c15;
+
+impl RngCore for SplitMix64 {
+ #[inline]
+ fn next_u32(&mut self) -> u32 {
+ self.x = self.x.wrapping_add(PHI);
+ let mut z = self.x;
+ // David Stafford's
+ // (http://zimbry.blogspot.com/2011/09/better-bit-mixing-improving-on.html)
+ // "Mix4" variant of the 64-bit finalizer in Austin Appleby's
+ // MurmurHash3 algorithm.
+ z = (z ^ (z >> 33)).wrapping_mul(0x62A9D9ED799705F5);
+ z = (z ^ (z >> 28)).wrapping_mul(0xCB24D0A5C88C35B3);
+ (z >> 32) as u32
+ }
+
+ #[inline]
+ fn next_u64(&mut self) -> u64 {
+ self.x = self.x.wrapping_add(PHI);
+ let mut z = self.x;
+ z = (z ^ (z >> 30)).wrapping_mul(0xbf58476d1ce4e5b9);
+ z = (z ^ (z >> 27)).wrapping_mul(0x94d049bb133111eb);
+ z ^ (z >> 31)
+ }
+
+ #[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(())
+ }
+}
+
+impl SeedableRng for SplitMix64 {
+ type Seed = [u8; 8];
+
+ /// Create a new `SplitMix64`.
+ fn from_seed(seed: [u8; 8]) -> SplitMix64 {
+ let mut state = [0; 1];
+ read_u64_into(&seed, &mut state);
+ SplitMix64 {
+ x: state[0],
+ }
+ }
+
+ /// Seed a `SplitMix64` from a `u64`.
+ fn seed_from_u64(seed: u64) -> SplitMix64 {
+ let mut x = [0; 8];
+ LittleEndian::write_u64(&mut x, seed);
+ SplitMix64::from_seed(x)
+ }
+}
+
+#[cfg(test)]
+mod tests {
+ use super::*;
+
+ #[test]
+ fn reference() {
+ let mut rng = SplitMix64::seed_from_u64(1477776061723855037);
+ // These values were produced with the reference implementation:
+ // http://xoshiro.di.unimi.it/splitmix64.c
+ let expected : [u64 ; 50]= [
+ 1985237415132408290, 2979275885539914483, 13511426838097143398,
+ 8488337342461049707, 15141737807933549159, 17093170987380407015,
+ 16389528042912955399, 13177319091862933652, 10841969400225389492,
+ 17094824097954834098, 3336622647361835228, 9678412372263018368,
+ 11111587619974030187, 7882215801036322410, 5709234165213761869,
+ 7799681907651786826, 4616320717312661886, 4251077652075509767,
+ 7836757050122171900, 5054003328188417616, 12919285918354108358,
+ 16477564761813870717, 5124667218451240549, 18099554314556827626,
+ 7603784838804469118, 6358551455431362471, 3037176434532249502,
+ 3217550417701719149, 9958699920490216947, 5965803675992506258,
+ 12000828378049868312, 12720568162811471118, 245696019213873792,
+ 8351371993958923852, 14378754021282935786, 5655432093647472106,
+ 5508031680350692005, 8515198786865082103, 6287793597487164412,
+ 14963046237722101617, 3630795823534910476, 8422285279403485710,
+ 10554287778700714153, 10871906555720704584, 8659066966120258468,
+ 9420238805069527062, 10338115333623340156, 13514802760105037173,
+ 14635952304031724449, 15419692541594102413,
+ ];
+ for &e in expected.iter() {
+ assert_eq!(rng.next_u64(), e);
+ }
+ }
+
+ #[test]
+ fn next_u32() {
+ let mut rng = SplitMix64::seed_from_u64(10);
+ // These values were produced with the reference implementation:
+ // http://dsiutils.di.unimi.it/dsiutils-2.5.1-src.tar.gz
+ let expected : [u32 ; 100]= [
+ 3930361779, 4016923089, 4113052479, 925926767, 1755287528,
+ 802865554, 954171070, 3724185978, 173676273, 1414488795, 12664133,
+ 1784889697, 1303817078, 261610523, 941280008, 2571813643,
+ 2954453492, 378291111, 2546873158, 3923319175, 645257028,
+ 3881821278, 2681538690, 3037029984, 1999958137, 1853970361,
+ 2989951788, 2126166628, 839962987, 3989679659, 3656977858,
+ 684284364, 1673258011, 170979192, 3037622326, 1600748179,
+ 1780764218, 1141430714, 4139736875, 3336905707, 2262051600,
+ 3830850262, 2430765325, 1073032139, 1668888979, 2716938970,
+ 4102420032, 40305196, 386350562, 2754480591, 622869439, 2129598760,
+ 2306038241, 4218338739, 412298926, 3453855056, 3061469690,
+ 4284292697, 994843708, 1591016681, 414726151, 1238182607, 18073498,
+ 1237631493, 351884714, 2347486264, 2488990876, 802846256, 645670443,
+ 957607012, 3126589776, 1966356370, 3036485766, 868696717,
+ 2808613630, 2070968151, 1025536863, 1743949425, 466212687,
+ 2994327271, 209776458, 1246125124, 3344380309, 2203947859,
+ 968313105, 2805485302, 197484837, 3472483632, 3931823935,
+ 3288490351, 4165666529, 3671080416, 689542830, 1272555356,
+ 1039141475, 3984640460, 4142959054, 2252788890, 2459379590,
+ 991872507,
+ ];
+ for &e in expected.iter() {
+ assert_eq!(rng.next_u32(), e);
+ }
+ }
+}