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

1 files changed, 132 insertions, 0 deletions

diff --git a/rand/rand_xoshiro/src/xoroshiro128plus.rs b/rand/rand_xoshiro/src/xoroshiro128plus.rs
new file mode 100644
index 0000000..df032c8
--- /dev/null
+++ b/rand/rand_xoshiro/src/xoroshiro128plus.rs
@@ -0,0 +1,132 @@
+// 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 rand_core;
+use rand_core::le::read_u64_into;
+use rand_core::impls::fill_bytes_via_next;
+use rand_core::{RngCore, SeedableRng};
+
+/// A xoroshiro128+ random number generator.
+///
+/// The xoroshiro128+ 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 `xoroshiro128plus.c`
+/// reference source code](http://xoshiro.di.unimi.it/xoroshiro128plus.c) by
+/// David Blackman and Sebastiano Vigna.
+#[allow(missing_copy_implementations)]
+#[derive(Debug, Clone)]
+pub struct Xoroshiro128Plus {
+    s0: u64,
+    s1: u64,
+}
+
+impl Xoroshiro128Plus {
+    /// Jump forward, equivalently to 2^64 calls to `next_u64()`.
+    ///
+    /// 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::Xoroshiro128Plus;
+    ///
+    /// let rng1 = Xoroshiro128Plus::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!(u64, self, [0xdf900294d8f554a5, 0x170865df4b3201fc]);
+    }
+
+    /// Jump forward, equivalently to 2^96 calls to `next_u64()`.
+    ///
+    /// This can be used to generate 2^32 starting points, from each of which
+    /// `jump()` will generate 2^32 non-overlapping subsequences for parallel
+    /// distributed computations.
+    pub fn long_jump(&mut self) {
+        impl_jump!(u64, self, [0xd2a98b26625eee7b, 0xdddf9b1090aa7ac1]);
+    }
+}
+
+impl RngCore for Xoroshiro128Plus {
+    #[inline]
+    fn next_u32(&mut self) -> u32 {
+        // The two lowest bits have some linear dependencies, so we use the
+        // upper bits instead.
+        (self.next_u64() >> 32) as u32
+    }
+
+    #[inline]
+    fn next_u64(&mut self) -> u64 {
+        let r = self.s0.wrapping_add(self.s1);
+        impl_xoroshiro_u64!(self);
+        r
+    }
+
+    #[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<(), rand_core::Error> {
+        self.fill_bytes(dest);
+        Ok(())
+    }
+}
+
+impl SeedableRng for Xoroshiro128Plus {
+    type Seed = [u8; 16];
+
+    /// Create a new `Xoroshiro128Plus`.  If `seed` is entirely 0, it will be
+    /// mapped to a different seed.
+    fn from_seed(seed: [u8; 16]) -> Xoroshiro128Plus {
+        deal_with_zero_seed!(seed, Self);
+        let mut s = [0; 2];
+        read_u64_into(&seed, &mut s);
+
+        Xoroshiro128Plus {
+            s0: s[0],
+            s1: s[1],
+        }
+    }
+
+    /// Seed a `Xoroshiro128Plus` from a `u64` using `SplitMix64`.
+    fn seed_from_u64(seed: u64) -> Xoroshiro128Plus {
+        from_splitmix!(seed)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn reference() {
+        let mut rng = Xoroshiro128Plus::from_seed(
+            [1, 0, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0]);
+        // These values were produced with the reference implementation:
+        // http://xoshiro.di.unimi.it/xoshiro128starstar.c
+        let expected = [
+            3, 412333834243, 2360170716294286339, 9295852285959843169,
+            2797080929874688578, 6019711933173041966, 3076529664176959358,
+            3521761819100106140, 7493067640054542992, 920801338098114767,
+        ];
+        for &e in &expected {
+            assert_eq!(rng.next_u64(), e);
+        }
+    }
+}