Update nitrokey crate to 0.2.3

This change updates the nitrokey crate to version 0.2.3. This version
bumps the rand crate used to 0.6.1, which in turn requires an additional
set of dependencies.

Import subrepo nitrokey/:nitrokey at b3e2adc5bb1300441ca74cc7672617c042f3ea31
Import subrepo rand/:rand at 73613ff903512e9503e41cc8ba9eae76269dc598
Import subrepo rustc_version/:rustc_version at 0294f2ba2018bf7be672abd53db351ce5055fa02
Import subrepo semver-parser/:semver-parser at 750da9b11a04125231b1fb293866ca036845acee
Import subrepo semver/:semver at 5eb6db94fa03f4d5c64a625a56188f496be47598

4 files changed, 1137 insertions, 0 deletions

diff --git a/rand/rand_isaac/src/isaac.rs b/rand/rand_isaac/src/isaac.rs
new file mode 100644
index 0000000..2bfdd94
--- /dev/null
+++ b/rand/rand_isaac/src/isaac.rs
@@ -0,0 +1,484 @@
+// Copyright 2018 Developers of the Rand project.
+// Copyright 2013-2018 The Rust Project Developers.
+//
+// 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.
+
+//! The ISAAC random number generator.
+
+use core::{fmt, slice};
+use core::num::Wrapping as w;
+use rand_core::{RngCore, SeedableRng, Error, le};
+use rand_core::block::{BlockRngCore, BlockRng};
+use isaac_array::IsaacArray;
+
+#[allow(non_camel_case_types)]
+type w32 = w<u32>;
+
+const RAND_SIZE_LEN: usize = 8;
+const RAND_SIZE: usize = 1 << RAND_SIZE_LEN;
+
+/// A random number generator that uses the ISAAC algorithm.
+///
+/// ISAAC stands for "Indirection, Shift, Accumulate, Add, and Count" which are
+/// the principal bitwise operations employed. It is the most advanced of a
+/// series of array based random number generator designed by Robert Jenkins
+/// in 1996[^1][^2].
+///
+/// ISAAC is notably fast and produces excellent quality random numbers for
+/// non-cryptographic applications.
+///
+/// In spite of being designed with cryptographic security in mind, ISAAC hasn't
+/// been stringently cryptanalyzed and thus cryptographers do not not
+/// consensually trust it to be secure. When looking for a secure RNG, prefer
+/// [`Hc128Rng`] instead, which, like ISAAC, is an array-based RNG and one of
+/// the stream-ciphers selected the by eSTREAM contest.
+///
+/// In 2006 an improvement to ISAAC was suggested by Jean-Philippe Aumasson,
+/// named ISAAC+[^3]. But because the specification is not complete, because
+/// there is no good implementation, and because the suggested bias may not
+/// exist, it is not implemented here.
+///
+/// ## Overview of the ISAAC algorithm:
+/// (in pseudo-code)
+///
+/// ```text
+/// Input: a, b, c, s[256] // state
+/// Output: r[256]         // results
+///
+/// mix(a,i) = a ^ a << 13   if i = 0 mod 4
+///            a ^ a >>  6   if i = 1 mod 4
+///            a ^ a <<  2   if i = 2 mod 4
+///            a ^ a >> 16   if i = 3 mod 4
+///
+/// c = c + 1
+/// b = b + c
+///
+/// for i in 0..256 {
+///     x = s_[i]
+///     a = f(a,i) + s[i+128 mod 256]
+///     y = a + b + s[x>>2 mod 256]
+///     s[i] = y
+///     b = x + s[y>>10 mod 256]
+///     r[i] = b
+/// }
+/// ```
+///
+/// Numbers are generated in blocks of 256. This means the function above only
+/// runs once every 256 times you ask for a next random number. In all other
+/// circumstances the last element of the results array is returned.
+///
+/// ISAAC therefore needs a lot of memory, relative to other non-crypto RNGs.
+/// 2 * 256 * 4 = 2 kb to hold the state and results.
+///
+/// This implementation uses [`BlockRng`] to implement the [`RngCore`] methods.
+///
+/// ## References
+/// [^1]: Bob Jenkins, [*ISAAC: A fast cryptographic random number generator*](
+///       http://burtleburtle.net/bob/rand/isaacafa.html)
+///
+/// [^2]: Bob Jenkins, [*ISAAC and RC4*](
+///       http://burtleburtle.net/bob/rand/isaac.html)
+///
+/// [^3]: Jean-Philippe Aumasson, [*On the pseudo-random generator ISAAC*](
+///       https://eprint.iacr.org/2006/438)
+///
+/// [`Hc128Rng`]: ../../rand_hc/struct.Hc128Rng.html
+/// [`BlockRng`]: ../../rand_core/block/struct.BlockRng.html
+/// [`RngCore`]: ../../rand_core/trait.RngCore.html
+#[derive(Clone, Debug)]
+#[cfg_attr(feature="serde1", derive(Serialize, Deserialize))]
+pub struct IsaacRng(BlockRng<IsaacCore>);
+
+impl RngCore for IsaacRng {
+    #[inline(always)]
+    fn next_u32(&mut self) -> u32 {
+        self.0.next_u32()
+    }
+
+    #[inline(always)]
+    fn next_u64(&mut self) -> u64 {
+        self.0.next_u64()
+    }
+
+    fn fill_bytes(&mut self, dest: &mut [u8]) {
+        self.0.fill_bytes(dest)
+    }
+
+    fn try_fill_bytes(&mut self, dest: &mut [u8]) -> Result<(), Error> {
+        self.0.try_fill_bytes(dest)
+    }
+}
+
+impl SeedableRng for IsaacRng {
+    type Seed = <IsaacCore as SeedableRng>::Seed;
+
+    fn from_seed(seed: Self::Seed) -> Self {
+        IsaacRng(BlockRng::<IsaacCore>::from_seed(seed))
+    }
+    
+    /// Create an ISAAC random number generator using an `u64` as seed.
+    /// If `seed == 0` this will produce the same stream of random numbers as
+    /// the reference implementation when used unseeded.
+    fn seed_from_u64(seed: u64) -> Self {
+        IsaacRng(BlockRng::<IsaacCore>::seed_from_u64(seed))
+    }
+
+    fn from_rng<S: RngCore>(rng: S) -> Result<Self, Error> {
+        BlockRng::<IsaacCore>::from_rng(rng).map(|rng| IsaacRng(rng))
+    }
+}
+
+impl IsaacRng {
+    /// Create an ISAAC random number generator using an `u64` as seed.
+    /// If `seed == 0` this will produce the same stream of random numbers as
+    /// the reference implementation when used unseeded.
+    #[deprecated(since="0.6.0", note="use SeedableRng::seed_from_u64 instead")]
+    pub fn new_from_u64(seed: u64) -> Self {
+        Self::seed_from_u64(seed)
+    }
+}
+
+/// The core of `IsaacRng`, used with `BlockRng`.
+#[derive(Clone)]
+#[cfg_attr(feature="serde1", derive(Serialize, Deserialize))]
+pub struct IsaacCore {
+    #[cfg_attr(feature="serde1",serde(with="super::isaac_array::isaac_array_serde"))]
+    mem: [w32; RAND_SIZE],
+    a: w32,
+    b: w32,
+    c: w32,
+}
+
+// Custom Debug implementation that does not expose the internal state
+impl fmt::Debug for IsaacCore {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(f, "IsaacCore {{}}")
+    }
+}
+
+impl BlockRngCore for IsaacCore {
+    type Item = u32;
+    type Results = IsaacArray<Self::Item>;
+
+    /// Refills the output buffer, `results`. See also the pseudocode desciption
+    /// of the algorithm in the [`IsaacRng`] documentation.
+    ///
+    /// Optimisations used (similar to the reference implementation):
+    /// 
+    /// - The loop is unrolled 4 times, once for every constant of mix().
+    /// - The contents of the main loop are moved to a function `rngstep`, to
+    ///   reduce code duplication.
+    /// - We use local variables for a and b, which helps with optimisations.
+    /// - We split the main loop in two, one that operates over 0..128 and one
+    ///   over 128..256. This way we can optimise out the addition and modulus
+    ///   from `s[i+128 mod 256]`.
+    /// - We maintain one index `i` and add `m` or `m2` as base (m2 for the
+    ///   `s[i+128 mod 256]`), relying on the optimizer to turn it into pointer
+    ///   arithmetic.
+    /// - We fill `results` backwards. The reference implementation reads values
+    ///   from `results` in reverse. We read them in the normal direction, to
+    ///   make `fill_bytes` a memcopy. To maintain compatibility we fill in
+    ///   reverse.
+    /// 
+    /// [`IsaacRng`]: struct.IsaacRng.html
+    fn generate(&mut self, results: &mut IsaacArray<Self::Item>) {
+        self.c += w(1);
+        // abbreviations
+        let mut a = self.a;
+        let mut b = self.b + self.c;
+        const MIDPOINT: usize = RAND_SIZE / 2;
+
+        #[inline]
+        fn ind(mem:&[w32; RAND_SIZE], v: w32, amount: usize) -> w32 {
+            let index = (v >> amount).0 as usize % RAND_SIZE;
+            mem[index]
+        }
+
+        #[inline]
+        fn rngstep(mem: &mut [w32; RAND_SIZE],
+                   results: &mut [u32; RAND_SIZE],
+                   mix: w32,
+                   a: &mut w32,
+                   b: &mut w32,
+                   base: usize,
+                   m: usize,
+                   m2: usize) {
+            let x = mem[base + m];
+            *a = mix + mem[base + m2];
+            let y = *a + *b + ind(&mem, x, 2);
+            mem[base + m] = y;
+            *b = x + ind(&mem, y, 2 + RAND_SIZE_LEN);
+            results[RAND_SIZE - 1 - base - m] = (*b).0;
+        }
+
+        let mut m = 0;
+        let mut m2 = MIDPOINT;
+        for i in (0..MIDPOINT/4).map(|i| i * 4) {
+            rngstep(&mut self.mem, results, a ^ (a << 13), &mut a, &mut b, i + 0, m, m2);
+            rngstep(&mut self.mem, results, a ^ (a >> 6 ),  &mut a, &mut b, i + 1, m, m2);
+            rngstep(&mut self.mem, results, a ^ (a << 2 ),  &mut a, &mut b, i + 2, m, m2);
+            rngstep(&mut self.mem, results, a ^ (a >> 16),  &mut a, &mut b, i + 3, m, m2);
+        }
+
+        m = MIDPOINT;
+        m2 = 0;
+        for i in (0..MIDPOINT/4).map(|i| i * 4) {
+            rngstep(&mut self.mem, results, a ^ (a << 13), &mut a, &mut b, i + 0, m, m2);
+            rngstep(&mut self.mem, results, a ^ (a >> 6 ),  &mut a, &mut b, i + 1, m, m2);
+            rngstep(&mut self.mem, results, a ^ (a << 2 ),  &mut a, &mut b, i + 2, m, m2);
+            rngstep(&mut self.mem, results, a ^ (a >> 16),  &mut a, &mut b, i + 3, m, m2);
+        }
+
+        self.a = a;
+        self.b = b;
+    }
+}
+
+impl IsaacCore {
+    /// Create a new ISAAC random number generator.
+    ///
+    /// The author Bob Jenkins describes how to best initialize ISAAC here:
+    /// <https://rt.cpan.org/Public/Bug/Display.html?id=64324>
+    /// The answer is included here just in case:
+    ///
+    /// "No, you don't need a full 8192 bits of seed data. Normal key sizes will
+    /// do fine, and they should have their expected strength (eg a 40-bit key
+    /// will take as much time to brute force as 40-bit keys usually will). You
+    /// could fill the remainder with 0, but set the last array element to the
+    /// length of the key provided (to distinguish keys that differ only by
+    /// different amounts of 0 padding). You do still need to call `randinit()`
+    /// to make sure the initial state isn't uniform-looking."
+    /// "After publishing ISAAC, I wanted to limit the key to half the size of
+    /// `r[]`, and repeat it twice. That would have made it hard to provide a
+    /// key that sets the whole internal state to anything convenient. But I'd
+    /// already published it."
+    ///
+    /// And his answer to the question "For my code, would repeating the key
+    /// over and over to fill 256 integers be a better solution than
+    /// zero-filling, or would they essentially be the same?":
+    /// "If the seed is under 32 bytes, they're essentially the same, otherwise
+    /// repeating the seed would be stronger. randinit() takes a chunk of 32
+    /// bytes, mixes it, and combines that with the next 32 bytes, et cetera.
+    /// Then loops over all the elements the same way a second time."
+    #[inline]
+    fn init(mut mem: [w32; RAND_SIZE], rounds: u32) -> Self {
+        fn mix(a: &mut w32, b: &mut w32, c: &mut w32, d: &mut w32,
+               e: &mut w32, f: &mut w32, g: &mut w32, h: &mut w32) {
+            *a ^= *b << 11; *d += *a; *b += *c;
+            *b ^= *c >> 2;  *e += *b; *c += *d;
+            *c ^= *d << 8;  *f += *c; *d += *e;
+            *d ^= *e >> 16; *g += *d; *e += *f;
+            *e ^= *f << 10; *h += *e; *f += *g;
+            *f ^= *g >> 4;  *a += *f; *g += *h;
+            *g ^= *h << 8;  *b += *g; *h += *a;
+            *h ^= *a >> 9;  *c += *h; *a += *b;
+        }
+
+        // These numbers are the result of initializing a...h with the
+        // fractional part of the golden ratio in binary (0x9e3779b9)
+        // and applying mix() 4 times.
+        let mut a = w(0x1367df5a);
+        let mut b = w(0x95d90059);
+        let mut c = w(0xc3163e4b);
+        let mut d = w(0x0f421ad8);
+        let mut e = w(0xd92a4a78);
+        let mut f = w(0xa51a3c49);
+        let mut g = w(0xc4efea1b);
+        let mut h = w(0x30609119);
+
+        // Normally this should do two passes, to make all of the seed effect
+        // all of `mem`
+        for _ in 0..rounds {
+            for i in (0..RAND_SIZE/8).map(|i| i * 8) {
+                a += mem[i  ]; b += mem[i+1];
+                c += mem[i+2]; d += mem[i+3];
+                e += mem[i+4]; f += mem[i+5];
+                g += mem[i+6]; h += mem[i+7];
+                mix(&mut a, &mut b, &mut c, &mut d,
+                    &mut e, &mut f, &mut g, &mut h);
+                mem[i  ] = a; mem[i+1] = b;
+                mem[i+2] = c; mem[i+3] = d;
+                mem[i+4] = e; mem[i+5] = f;
+                mem[i+6] = g; mem[i+7] = h;
+            }
+        }
+
+        Self { mem, a: w(0), b: w(0), c: w(0) }
+    }
+}
+
+impl SeedableRng for IsaacCore {
+    type Seed = [u8; 32];
+
+    fn from_seed(seed: Self::Seed) -> Self {
+        let mut seed_u32 = [0u32; 8];
+        le::read_u32_into(&seed, &mut seed_u32);
+        // Convert the seed to `Wrapping<u32>` and zero-extend to `RAND_SIZE`.
+        let mut seed_extended = [w(0); RAND_SIZE];
+        for (x, y) in seed_extended.iter_mut().zip(seed_u32.iter()) {
+            *x = w(*y);
+        }
+        Self::init(seed_extended, 2)
+    }
+    
+    /// Create an ISAAC random number generator using an `u64` as seed.
+    /// If `seed == 0` this will produce the same stream of random numbers as
+    /// the reference implementation when used unseeded.
+    fn seed_from_u64(seed: u64) -> Self {
+        let mut key = [w(0); RAND_SIZE];
+        key[0] = w(seed as u32);
+        key[1] = w((seed >> 32) as u32);
+        // Initialize with only one pass.
+        // A second pass does not improve the quality here, because all of the
+        // seed was already available in the first round.
+        // Not doing the second pass has the small advantage that if
+        // `seed == 0` this method produces exactly the same state as the
+        // reference implementation when used unseeded.
+        Self::init(key, 1)
+    }
+
+    fn from_rng<R: RngCore>(mut rng: R) -> Result<Self, Error> {
+        // Custom `from_rng` implementation that fills a seed with the same size
+        // as the entire state.
+        let mut seed = [w(0u32); RAND_SIZE];
+        unsafe {
+            let ptr = seed.as_mut_ptr() as *mut u8;
+
+            let slice = slice::from_raw_parts_mut(ptr, RAND_SIZE * 4);
+            rng.try_fill_bytes(slice)?;
+        }
+        for i in seed.iter_mut() {
+            *i = w(i.0.to_le());
+        }
+
+        Ok(Self::init(seed, 2))
+    }
+}
+
+#[cfg(test)]
+mod test {
+    use rand_core::{RngCore, SeedableRng};
+    use super::IsaacRng;
+
+    #[test]
+    fn test_isaac_construction() {
+        // Test that various construction techniques produce a working RNG.
+        let seed = [1,0,0,0, 23,0,0,0, 200,1,0,0, 210,30,0,0,
+                    0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0];
+        let mut rng1 = IsaacRng::from_seed(seed);
+        assert_eq!(rng1.next_u32(), 2869442790);
+
+        let mut rng2 = IsaacRng::from_rng(rng1).unwrap();
+        assert_eq!(rng2.next_u32(), 3094074039);
+    }
+
+    #[test]
+    fn test_isaac_true_values_32() {
+        let seed = [1,0,0,0, 23,0,0,0, 200,1,0,0, 210,30,0,0,
+                     57,48,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0];
+        let mut rng1 = IsaacRng::from_seed(seed);
+        let mut results = [0u32; 10];
+        for i in results.iter_mut() { *i = rng1.next_u32(); }
+        let expected = [
+            2558573138, 873787463, 263499565, 2103644246, 3595684709,
+            4203127393, 264982119, 2765226902, 2737944514, 3900253796];
+        assert_eq!(results, expected);
+
+        let seed = [57,48,0,0, 50,9,1,0, 49,212,0,0, 148,38,0,0,
+                    0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0];
+        let mut rng2 = IsaacRng::from_seed(seed);
+        // skip forward to the 10000th number
+        for _ in 0..10000 { rng2.next_u32(); }
+
+        for i in results.iter_mut() { *i = rng2.next_u32(); }
+        let expected = [
+            3676831399, 3183332890, 2834741178, 3854698763, 2717568474,
+            1576568959, 3507990155, 179069555, 141456972, 2478885421];
+        assert_eq!(results, expected);
+    }
+
+    #[test]
+    fn test_isaac_true_values_64() {
+        // As above, using little-endian versions of above values
+        let seed = [1,0,0,0, 23,0,0,0, 200,1,0,0, 210,30,0,0,
+                    57,48,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0];
+        let mut rng = IsaacRng::from_seed(seed);
+        let mut results = [0u64; 5];
+        for i in results.iter_mut() { *i = rng.next_u64(); }
+        let expected = [
+            3752888579798383186, 9035083239252078381,18052294697452424037,
+            11876559110374379111, 16751462502657800130];
+        assert_eq!(results, expected);
+    }
+
+    #[test]
+    fn test_isaac_true_bytes() {
+        let seed = [1,0,0,0, 23,0,0,0, 200,1,0,0, 210,30,0,0,
+                     57,48,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0];
+        let mut rng = IsaacRng::from_seed(seed);
+        let mut results = [0u8; 32];
+        rng.fill_bytes(&mut results);
+        // Same as first values in test_isaac_true_values as bytes in LE order
+        let expected = [82, 186, 128, 152, 71, 240, 20, 52,
+                        45, 175, 180, 15, 86, 16, 99, 125,
+                        101, 203, 81, 214, 97, 162, 134, 250,
+                        103, 78, 203, 15, 150, 3, 210, 164];
+        assert_eq!(results, expected);
+    }
+
+    #[test]
+    fn test_isaac_new_uninitialized() {
+        // Compare the results from initializing `IsaacRng` with
+        // `seed_from_u64(0)`, to make sure it is the same as the reference
+        // implementation when used uninitialized.
+        // Note: We only test the first 16 integers, not the full 256 of the
+        // first block.
+        let mut rng = IsaacRng::seed_from_u64(0);
+        let mut results = [0u32; 16];
+        for i in results.iter_mut() { *i = rng.next_u32(); }
+        let expected: [u32; 16] = [
+            0x71D71FD2, 0xB54ADAE7, 0xD4788559, 0xC36129FA,
+            0x21DC1EA9, 0x3CB879CA, 0xD83B237F, 0xFA3CE5BD,
+            0x8D048509, 0xD82E9489, 0xDB452848, 0xCA20E846,
+            0x500F972E, 0x0EEFF940, 0x00D6B993, 0xBC12C17F];
+        assert_eq!(results, expected);
+    }
+
+    #[test]
+    fn test_isaac_clone() {
+        let seed = [1,0,0,0, 23,0,0,0, 200,1,0,0, 210,30,0,0,
+                     57,48,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0];
+        let mut rng1 = IsaacRng::from_seed(seed);
+        let mut rng2 = rng1.clone();
+        for _ in 0..16 {
+            assert_eq!(rng1.next_u32(), rng2.next_u32());
+        }
+    }
+
+    #[test]
+    #[cfg(feature="serde1")]
+    fn test_isaac_serde() {
+        use bincode;
+        use std::io::{BufWriter, BufReader};
+
+        let seed = [1,0,0,0, 23,0,0,0, 200,1,0,0, 210,30,0,0,
+                     57,48,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0];
+        let mut rng = IsaacRng::from_seed(seed);
+
+        let buf: Vec<u8> = Vec::new();
+        let mut buf = BufWriter::new(buf);
+        bincode::serialize_into(&mut buf, &rng).expect("Could not serialize");
+
+        let buf = buf.into_inner().unwrap();
+        let mut read = BufReader::new(&buf[..]);
+        let mut deserialized: IsaacRng = bincode::deserialize_from(&mut read).expect("Could not deserialize");
+
+        for _ in 0..300 { // more than the 256 buffered results
+            assert_eq!(rng.next_u32(), deserialized.next_u32());
+        }
+    }
+}
diff --git a/rand/rand_isaac/src/isaac64.rs b/rand/rand_isaac/src/isaac64.rs
new file mode 100644
index 0000000..2712762
--- /dev/null
+++ b/rand/rand_isaac/src/isaac64.rs
@@ -0,0 +1,481 @@
+// Copyright 2018 Developers of the Rand project.
+// Copyright 2013-2018 The Rust Project Developers.
+//
+// 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.
+
+//! The ISAAC-64 random number generator.
+
+use core::{fmt, slice};
+use core::num::Wrapping as w;
+use rand_core::{RngCore, SeedableRng, Error, le};
+use rand_core::block::{BlockRngCore, BlockRng64};
+use isaac_array::IsaacArray;
+
+#[allow(non_camel_case_types)]
+type w64 = w<u64>;
+
+const RAND_SIZE_LEN: usize = 8;
+const RAND_SIZE: usize = 1 << RAND_SIZE_LEN;
+
+/// A random number generator that uses ISAAC-64, the 64-bit variant of the
+/// ISAAC algorithm.
+///
+/// ISAAC stands for "Indirection, Shift, Accumulate, Add, and Count" which are
+/// the principal bitwise operations employed. It is the most advanced of a
+/// series of array based random number generator designed by Robert Jenkins
+/// in 1996[^1].
+///
+/// ISAAC-64 is mostly similar to ISAAC. Because it operates on 64-bit integers
+/// instead of 32-bit, it uses twice as much memory to hold its state and
+/// results. Also it uses different constants for shifts and indirect indexing,
+/// optimized to give good results for 64bit arithmetic.
+///
+/// ISAAC-64 is notably fast and produces excellent quality random numbers for
+/// non-cryptographic applications.
+///
+/// In spite of being designed with cryptographic security in mind, ISAAC hasn't
+/// been stringently cryptanalyzed and thus cryptographers do not not
+/// consensually trust it to be secure. When looking for a secure RNG, prefer
+/// [`Hc128Rng`] instead, which, like ISAAC, is an array-based RNG and one of
+/// the stream-ciphers selected the by eSTREAM contest.
+///
+/// ## Overview of the ISAAC-64 algorithm:
+/// (in pseudo-code)
+///
+/// ```text
+/// Input: a, b, c, s[256] // state
+/// Output: r[256] // results
+///
+/// mix(a,i) = !(a ^ a << 21)  if i = 0 mod 4
+///              a ^ a >>  5   if i = 1 mod 4
+///              a ^ a << 12   if i = 2 mod 4
+///              a ^ a >> 33   if i = 3 mod 4
+///
+/// c = c + 1
+/// b = b + c
+///
+/// for i in 0..256 {
+///     x = s_[i]
+///     a = mix(a,i) + s[i+128 mod 256]
+///     y = a + b + s[x>>3 mod 256]
+///     s[i] = y
+///     b = x + s[y>>11 mod 256]
+///     r[i] = b
+/// }
+/// ```
+///
+/// This implementation uses [`BlockRng64`] to implement the [`RngCore`] methods.
+///
+/// See for more information the documentation of [`IsaacRng`].
+///
+/// [^1]: Bob Jenkins, [*ISAAC and RC4*](
+///       http://burtleburtle.net/bob/rand/isaac.html)
+///
+/// [`IsaacRng`]: ../isaac/struct.IsaacRng.html
+/// [`Hc128Rng`]: ../../rand_hc/struct.Hc128Rng.html
+/// [`BlockRng64`]: ../../rand_core/block/struct.BlockRng64.html
+/// [`RngCore`]: ../../rand_core/trait.RngCore.html
+#[derive(Clone, Debug)]
+#[cfg_attr(feature="serde1", derive(Serialize, Deserialize))]
+pub struct Isaac64Rng(BlockRng64<Isaac64Core>);
+
+impl RngCore for Isaac64Rng {
+    #[inline(always)]
+    fn next_u32(&mut self) -> u32 {
+        self.0.next_u32()
+    }
+
+    #[inline(always)]
+    fn next_u64(&mut self) -> u64 {
+        self.0.next_u64()
+    }
+
+    fn fill_bytes(&mut self, dest: &mut [u8]) {
+        self.0.fill_bytes(dest)
+    }
+
+    fn try_fill_bytes(&mut self, dest: &mut [u8]) -> Result<(), Error> {
+        self.0.try_fill_bytes(dest)
+    }
+}
+
+impl SeedableRng for Isaac64Rng {
+    type Seed = <Isaac64Core as SeedableRng>::Seed;
+
+    fn from_seed(seed: Self::Seed) -> Self {
+        Isaac64Rng(BlockRng64::<Isaac64Core>::from_seed(seed))
+    }
+
+    /// Create an ISAAC random number generator using an `u64` as seed.
+    /// If `seed == 0` this will produce the same stream of random numbers as
+    /// the reference implementation when used unseeded.
+    fn seed_from_u64(seed: u64) -> Self {
+        Isaac64Rng(BlockRng64::<Isaac64Core>::seed_from_u64(seed))
+    }
+
+    fn from_rng<S: RngCore>(rng: S) -> Result<Self, Error> {
+        BlockRng64::<Isaac64Core>::from_rng(rng).map(|rng| Isaac64Rng(rng))
+    }
+}
+
+impl Isaac64Rng {
+    /// Create an ISAAC-64 random number generator using an `u64` as seed.
+    /// If `seed == 0` this will produce the same stream of random numbers as
+    /// the reference implementation when used unseeded.
+    #[deprecated(since="0.6.0", note="use SeedableRng::seed_from_u64 instead")]
+    pub fn new_from_u64(seed: u64) -> Self {
+        Self::seed_from_u64(seed)
+    }
+}
+
+/// The core of `Isaac64Rng`, used with `BlockRng`.
+#[derive(Clone)]
+#[cfg_attr(feature="serde1", derive(Serialize, Deserialize))]
+pub struct Isaac64Core {
+    #[cfg_attr(feature="serde1",serde(with="super::isaac_array::isaac_array_serde"))]
+    mem: [w64; RAND_SIZE],
+    a: w64,
+    b: w64,
+    c: w64,
+}
+
+// Custom Debug implementation that does not expose the internal state
+impl fmt::Debug for Isaac64Core {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(f, "Isaac64Core {{}}")
+    }
+}
+
+impl BlockRngCore for Isaac64Core {
+    type Item = u64;
+    type Results = IsaacArray<Self::Item>;
+
+    /// Refills the output buffer, `results`. See also the pseudocode desciption
+    /// of the algorithm in the [`Isaac64Rng`] documentation.
+    ///
+    /// Optimisations used (similar to the reference implementation):
+    /// 
+    /// - The loop is unrolled 4 times, once for every constant of mix().
+    /// - The contents of the main loop are moved to a function `rngstep`, to
+    ///   reduce code duplication.
+    /// - We use local variables for a and b, which helps with optimisations.
+    /// - We split the main loop in two, one that operates over 0..128 and one
+    ///   over 128..256. This way we can optimise out the addition and modulus
+    ///   from `s[i+128 mod 256]`.
+    /// - We maintain one index `i` and add `m` or `m2` as base (m2 for the
+    ///   `s[i+128 mod 256]`), relying on the optimizer to turn it into pointer
+    ///   arithmetic.
+    /// - We fill `results` backwards. The reference implementation reads values
+    ///   from `results` in reverse. We read them in the normal direction, to
+    ///   make `fill_bytes` a memcopy. To maintain compatibility we fill in
+    ///   reverse.
+    /// 
+    /// [`Isaac64Rng`]: struct.Isaac64Rng.html
+    fn generate(&mut self, results: &mut IsaacArray<Self::Item>) {
+        self.c += w(1);
+        // abbreviations
+        let mut a = self.a;
+        let mut b = self.b + self.c;
+        const MIDPOINT: usize = RAND_SIZE / 2;
+
+        #[inline]
+        fn ind(mem:&[w64; RAND_SIZE], v: w64, amount: usize) -> w64 {
+            let index = (v >> amount).0 as usize % RAND_SIZE;
+            mem[index]
+        }
+
+        #[inline]
+        fn rngstep(mem: &mut [w64; RAND_SIZE],
+                   results: &mut [u64; RAND_SIZE],
+                   mix: w64,
+                   a: &mut w64,
+                   b: &mut w64,
+                   base: usize,
+                   m: usize,
+                   m2: usize) {
+            let x = mem[base + m];
+            *a = mix + mem[base + m2];
+            let y = *a + *b + ind(&mem, x, 3);
+            mem[base + m] = y;
+            *b = x + ind(&mem, y, 3 + RAND_SIZE_LEN);
+            results[RAND_SIZE - 1 - base - m] = (*b).0;
+        }
+
+        let mut m = 0;
+        let mut m2 = MIDPOINT;
+        for i in (0..MIDPOINT/4).map(|i| i * 4) {
+            rngstep(&mut self.mem, results, !(a ^ (a << 21)), &mut a, &mut b, i + 0, m, m2);
+            rngstep(&mut self.mem, results,   a ^ (a >> 5 ),  &mut a, &mut b, i + 1, m, m2);
+            rngstep(&mut self.mem, results,   a ^ (a << 12),  &mut a, &mut b, i + 2, m, m2);
+            rngstep(&mut self.mem, results,   a ^ (a >> 33),  &mut a, &mut b, i + 3, m, m2);
+        }
+
+        m = MIDPOINT;
+        m2 = 0;
+        for i in (0..MIDPOINT/4).map(|i| i * 4) {
+            rngstep(&mut self.mem, results, !(a ^ (a << 21)), &mut a, &mut b, i + 0, m, m2);
+            rngstep(&mut self.mem, results,   a ^ (a >> 5 ),  &mut a, &mut b, i + 1, m, m2);
+            rngstep(&mut self.mem, results,   a ^ (a << 12),  &mut a, &mut b, i + 2, m, m2);
+            rngstep(&mut self.mem, results,   a ^ (a >> 33),  &mut a, &mut b, i + 3, m, m2);
+        }
+
+        self.a = a;
+        self.b = b;
+    }
+}
+
+impl Isaac64Core {
+    /// Create a new ISAAC-64 random number generator.
+    fn init(mut mem: [w64; RAND_SIZE], rounds: u32) -> Self {
+        fn mix(a: &mut w64, b: &mut w64, c: &mut w64, d: &mut w64,
+               e: &mut w64, f: &mut w64, g: &mut w64, h: &mut w64) {
+            *a -= *e; *f ^= *h >> 9;  *h += *a;
+            *b -= *f; *g ^= *a << 9;  *a += *b;
+            *c -= *g; *h ^= *b >> 23; *b += *c;
+            *d -= *h; *a ^= *c << 15; *c += *d;
+            *e -= *a; *b ^= *d >> 14; *d += *e;
+            *f -= *b; *c ^= *e << 20; *e += *f;
+            *g -= *c; *d ^= *f >> 17; *f += *g;
+            *h -= *d; *e ^= *g << 14; *g += *h;
+        }
+
+        // These numbers are the result of initializing a...h with the
+        // fractional part of the golden ratio in binary (0x9e3779b97f4a7c13)
+        // and applying mix() 4 times.
+        let mut a = w(0x647c4677a2884b7c);
+        let mut b = w(0xb9f8b322c73ac862);
+        let mut c = w(0x8c0ea5053d4712a0);
+        let mut d = w(0xb29b2e824a595524);
+        let mut e = w(0x82f053db8355e0ce);
+        let mut f = w(0x48fe4a0fa5a09315);
+        let mut g = w(0xae985bf2cbfc89ed);
+        let mut h = w(0x98f5704f6c44c0ab);
+
+        // Normally this should do two passes, to make all of the seed effect
+        // all of `mem`
+        for _ in 0..rounds {
+            for i in (0..RAND_SIZE/8).map(|i| i * 8) {
+                a += mem[i  ]; b += mem[i+1];
+                c += mem[i+2]; d += mem[i+3];
+                e += mem[i+4]; f += mem[i+5];
+                g += mem[i+6]; h += mem[i+7];
+                mix(&mut a, &mut b, &mut c, &mut d,
+                    &mut e, &mut f, &mut g, &mut h);
+                mem[i  ] = a; mem[i+1] = b;
+                mem[i+2] = c; mem[i+3] = d;
+                mem[i+4] = e; mem[i+5] = f;
+                mem[i+6] = g; mem[i+7] = h;
+            }
+        }
+
+        Self { mem, a: w(0), b: w(0), c: w(0) }
+    }
+
+    /// Create an ISAAC-64 random number generator using an `u64` as seed.
+    /// If `seed == 0` this will produce the same stream of random numbers as
+    /// the reference implementation when used unseeded.
+    #[deprecated(since="0.6.0", note="use SeedableRng::seed_from_u64 instead")]
+    pub fn new_from_u64(seed: u64) -> Self {
+        Self::seed_from_u64(seed)
+    }
+}
+
+impl SeedableRng for Isaac64Core {
+    type Seed = [u8; 32];
+
+    fn from_seed(seed: Self::Seed) -> Self {
+        let mut seed_u64 = [0u64; 4];
+        le::read_u64_into(&seed, &mut seed_u64);
+        // Convert the seed to `Wrapping<u64>` and zero-extend to `RAND_SIZE`.
+        let mut seed_extended = [w(0); RAND_SIZE];
+        for (x, y) in seed_extended.iter_mut().zip(seed_u64.iter()) {
+            *x = w(*y);
+        }
+        Self::init(seed_extended, 2)
+    }
+    
+    fn seed_from_u64(seed: u64) -> Self {
+        let mut key = [w(0); RAND_SIZE];
+        key[0] = w(seed);
+        // Initialize with only one pass.
+        // A second pass does not improve the quality here, because all of the
+        // seed was already available in the first round.
+        // Not doing the second pass has the small advantage that if
+        // `seed == 0` this method produces exactly the same state as the
+        // reference implementation when used unseeded.
+        Self::init(key, 1)
+    }
+
+    fn from_rng<R: RngCore>(mut rng: R) -> Result<Self, Error> {
+        // Custom `from_rng` implementation that fills a seed with the same size
+        // as the entire state.
+        let mut seed = [w(0u64); RAND_SIZE];
+        unsafe {
+            let ptr = seed.as_mut_ptr() as *mut u8;
+            let slice = slice::from_raw_parts_mut(ptr, RAND_SIZE * 8);
+            rng.try_fill_bytes(slice)?;
+        }
+        for i in seed.iter_mut() {
+            *i = w(i.0.to_le());
+        }
+
+        Ok(Self::init(seed, 2))
+    }
+}
+
+#[cfg(test)]
+mod test {
+    use rand_core::{RngCore, SeedableRng};
+    use super::Isaac64Rng;
+
+    #[test]
+    fn test_isaac64_construction() {
+        // Test that various construction techniques produce a working RNG.
+        let seed = [1,0,0,0, 23,0,0,0, 200,1,0,0, 210,30,0,0,
+                    0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0];
+        let mut rng1 = Isaac64Rng::from_seed(seed);
+        assert_eq!(rng1.next_u64(), 14964555543728284049);
+
+        let mut rng2 = Isaac64Rng::from_rng(rng1).unwrap();
+        assert_eq!(rng2.next_u64(), 919595328260451758);
+    }
+
+    #[test]
+    fn test_isaac64_true_values_64() {
+        let seed = [1,0,0,0, 0,0,0,0, 23,0,0,0, 0,0,0,0,
+                    200,1,0,0, 0,0,0,0, 210,30,0,0, 0,0,0,0];
+        let mut rng1 = Isaac64Rng::from_seed(seed);
+        let mut results = [0u64; 10];
+        for i in results.iter_mut() { *i = rng1.next_u64(); }
+        let expected = [
+                   15071495833797886820, 7720185633435529318,
+                   10836773366498097981, 5414053799617603544,
+                   12890513357046278984, 17001051845652595546,
+                   9240803642279356310, 12558996012687158051,
+                   14673053937227185542, 1677046725350116783];
+        assert_eq!(results, expected);
+
+        let seed = [57,48,0,0, 0,0,0,0, 50,9,1,0, 0,0,0,0,
+                    49,212,0,0, 0,0,0,0, 148,38,0,0, 0,0,0,0];
+        let mut rng2 = Isaac64Rng::from_seed(seed);
+        // skip forward to the 10000th number
+        for _ in 0..10000 { rng2.next_u64(); }
+
+        for i in results.iter_mut() { *i = rng2.next_u64(); }
+        let expected = [
+            18143823860592706164, 8491801882678285927, 2699425367717515619,
+            17196852593171130876, 2606123525235546165, 15790932315217671084,
+            596345674630742204, 9947027391921273664, 11788097613744130851,
+            10391409374914919106];
+        assert_eq!(results, expected);
+    }
+
+    #[test]
+    fn test_isaac64_true_values_32() {
+        let seed = [1,0,0,0, 0,0,0,0, 23,0,0,0, 0,0,0,0,
+                    200,1,0,0, 0,0,0,0, 210,30,0,0, 0,0,0,0];
+        let mut rng = Isaac64Rng::from_seed(seed);
+        let mut results = [0u32; 12];
+        for i in results.iter_mut() { *i = rng.next_u32(); }
+        // Subset of above values, as an LE u32 sequence
+        let expected = [
+                    3477963620, 3509106075,
+                    687845478, 1797495790,
+                    227048253, 2523132918,
+                    4044335064, 1260557630,
+                    4079741768, 3001306521,
+                    69157722, 3958365844];
+        assert_eq!(results, expected);
+    }
+
+    #[test]
+    fn test_isaac64_true_values_mixed() {
+        let seed = [1,0,0,0, 0,0,0,0, 23,0,0,0, 0,0,0,0,
+                    200,1,0,0, 0,0,0,0, 210,30,0,0, 0,0,0,0];
+        let mut rng = Isaac64Rng::from_seed(seed);
+        // Test alternating between `next_u64` and `next_u32` works as expected.
+        // Values are the same as `test_isaac64_true_values` and
+        // `test_isaac64_true_values_32`.
+        assert_eq!(rng.next_u64(), 15071495833797886820);
+        assert_eq!(rng.next_u32(), 687845478);
+        assert_eq!(rng.next_u32(), 1797495790);
+        assert_eq!(rng.next_u64(), 10836773366498097981);
+        assert_eq!(rng.next_u32(), 4044335064);
+        // Skip one u32
+        assert_eq!(rng.next_u64(), 12890513357046278984);
+        assert_eq!(rng.next_u32(), 69157722);
+    }
+
+    #[test]
+    fn test_isaac64_true_bytes() {
+        let seed = [1,0,0,0, 0,0,0,0, 23,0,0,0, 0,0,0,0,
+                    200,1,0,0, 0,0,0,0, 210,30,0,0, 0,0,0,0];
+        let mut rng = Isaac64Rng::from_seed(seed);
+        let mut results = [0u8; 32];
+        rng.fill_bytes(&mut results);
+        // Same as first values in test_isaac64_true_values as bytes in LE order
+        let expected = [100, 131, 77, 207, 155, 181, 40, 209,
+                        102, 176, 255, 40, 238, 155, 35, 107,
+                        61, 123, 136, 13, 246, 243, 99, 150,
+                        216, 167, 15, 241, 62, 149, 34, 75];
+        assert_eq!(results, expected);
+    }
+
+    #[test]
+    fn test_isaac64_new_uninitialized() {
+        // Compare the results from initializing `IsaacRng` with
+        // `seed_from_u64(0)`, to make sure it is the same as the reference
+        // implementation when used uninitialized.
+        // Note: We only test the first 16 integers, not the full 256 of the
+        // first block.
+        let mut rng = Isaac64Rng::seed_from_u64(0);
+        let mut results = [0u64; 16];
+        for i in results.iter_mut() { *i = rng.next_u64(); }
+        let expected: [u64; 16] = [
+            0xF67DFBA498E4937C, 0x84A5066A9204F380, 0xFEE34BD5F5514DBB,
+            0x4D1664739B8F80D6, 0x8607459AB52A14AA, 0x0E78BC5A98529E49,
+            0xFE5332822AD13777, 0x556C27525E33D01A, 0x08643CA615F3149F,
+            0xD0771FAF3CB04714, 0x30E86F68A37B008D, 0x3074EBC0488A3ADF,
+            0x270645EA7A2790BC, 0x5601A0A8D3763C6A, 0x2F83071F53F325DD,
+            0xB9090F3D42D2D2EA];
+        assert_eq!(results, expected);
+    }
+
+    #[test]
+    fn test_isaac64_clone() {
+        let seed = [1,0,0,0, 0,0,0,0, 23,0,0,0, 0,0,0,0,
+                    200,1,0,0, 0,0,0,0, 210,30,0,0, 0,0,0,0];
+        let mut rng1 = Isaac64Rng::from_seed(seed);
+        let mut rng2 = rng1.clone();
+        for _ in 0..16 {
+            assert_eq!(rng1.next_u64(), rng2.next_u64());
+        }
+    }
+
+    #[test]
+    #[cfg(feature="serde1")]
+    fn test_isaac64_serde() {
+        use bincode;
+        use std::io::{BufWriter, BufReader};
+
+        let seed = [1,0,0,0, 23,0,0,0, 200,1,0,0, 210,30,0,0,
+                     57,48,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0];
+        let mut rng = Isaac64Rng::from_seed(seed);
+
+        let buf: Vec<u8> = Vec::new();
+        let mut buf = BufWriter::new(buf);
+        bincode::serialize_into(&mut buf, &rng).expect("Could not serialize");
+
+        let buf = buf.into_inner().unwrap();
+        let mut read = BufReader::new(&buf[..]);
+        let mut deserialized: Isaac64Rng = bincode::deserialize_from(&mut read).expect("Could not deserialize");
+
+        for _ in 0..300 { // more than the 256 buffered results
+            assert_eq!(rng.next_u64(), deserialized.next_u64());
+        }
+    }
+}
diff --git a/rand/rand_isaac/src/isaac_array.rs b/rand/rand_isaac/src/isaac_array.rs
new file mode 100644
index 0000000..0fa6147
--- /dev/null
+++ b/rand/rand_isaac/src/isaac_array.rs
@@ -0,0 +1,136 @@
+// Copyright 2018 Developers of the Rand project.
+// Copyright 2017-2018 The Rust Project Developers.
+//
+// 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.
+
+//! ISAAC helper functions for 256-element arrays.
+
+// Terrible workaround because arrays with more than 32 elements do not
+// implement `AsRef`, `Default`, `Serialize`, `Deserialize`, or any other
+// traits for that matter.
+
+#[cfg(feature="serde1")] use serde::{Serialize, Deserialize};
+
+const RAND_SIZE_LEN: usize = 8;
+const RAND_SIZE: usize = 1 << RAND_SIZE_LEN;
+
+
+#[derive(Copy, Clone)]
+#[allow(missing_debug_implementations)]
+#[cfg_attr(feature="serde1", derive(Serialize, Deserialize))]
+pub struct IsaacArray<T> {
+    #[cfg_attr(feature="serde1",serde(with="isaac_array_serde"))]
+    #[cfg_attr(feature="serde1", serde(bound(
+        serialize = "T: Serialize",
+        deserialize = "T: Deserialize<'de> + Copy + Default")))]
+    inner: [T; RAND_SIZE]
+}
+
+impl<T> ::core::convert::AsRef<[T]> for IsaacArray<T> {
+    #[inline(always)]
+    fn as_ref(&self) -> &[T] {
+        &self.inner[..]
+    }
+}
+
+impl<T> ::core::convert::AsMut<[T]> for IsaacArray<T> {
+    #[inline(always)]
+    fn as_mut(&mut self) -> &mut [T] {
+        &mut self.inner[..]
+    }
+}
+
+impl<T> ::core::ops::Deref for IsaacArray<T> {
+    type Target = [T; RAND_SIZE];
+    #[inline(always)]
+    fn deref(&self) -> &Self::Target {
+        &self.inner
+    }
+}
+
+impl<T> ::core::ops::DerefMut for IsaacArray<T> {
+    #[inline(always)]
+    fn deref_mut(&mut self) -> &mut [T; RAND_SIZE] {
+        &mut self.inner
+    }
+}
+
+impl<T> ::core::default::Default for IsaacArray<T> where T: Copy + Default {
+    fn default() -> IsaacArray<T> {
+        IsaacArray { inner: [T::default(); RAND_SIZE] }
+    }
+}
+
+
+#[cfg(feature="serde1")]
+pub(super) mod isaac_array_serde {
+    const RAND_SIZE_LEN: usize = 8;
+    const RAND_SIZE: usize = 1 << RAND_SIZE_LEN;
+
+    use serde::{Deserialize, Deserializer, Serialize, Serializer};
+    use serde::de::{Visitor,SeqAccess};
+    use serde::de;
+
+    use core::fmt;
+
+    pub fn serialize<T, S>(arr: &[T;RAND_SIZE], ser: S) -> Result<S::Ok, S::Error>
+    where
+        T: Serialize,
+        S: Serializer
+    {
+        use serde::ser::SerializeTuple;
+
+        let mut seq = ser.serialize_tuple(RAND_SIZE)?;
+
+        for e in arr.iter() {
+            seq.serialize_element(&e)?;
+        }
+
+        seq.end()
+    }
+
+    #[inline]
+    pub fn deserialize<'de, T, D>(de: D) -> Result<[T;RAND_SIZE], D::Error>
+    where
+        T: Deserialize<'de>+Default+Copy,
+        D: Deserializer<'de>,
+    {
+        use core::marker::PhantomData;
+        struct ArrayVisitor<T> {
+            _pd: PhantomData<T>,
+        };
+        impl<'de,T> Visitor<'de> for ArrayVisitor<T>
+        where
+            T: Deserialize<'de>+Default+Copy
+        {
+            type Value = [T; RAND_SIZE];
+
+            fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
+                formatter.write_str("Isaac state array")
+            }
+
+            #[inline]
+            fn visit_seq<A>(self, mut seq: A) -> Result<[T; RAND_SIZE], A::Error>
+            where
+                A: SeqAccess<'de>,
+            {
+                let mut out = [Default::default();RAND_SIZE];
+
+                for i in 0..RAND_SIZE {
+                    match seq.next_element()? {
+                        Some(val) => out[i] = val,
+                        None => return Err(de::Error::invalid_length(i, &self)),
+                    };
+                }
+
+                Ok(out)
+            }
+        }
+
+        de.deserialize_tuple(RAND_SIZE, ArrayVisitor{_pd: PhantomData})
+    }
+}
diff --git a/rand/rand_isaac/src/lib.rs b/rand/rand_isaac/src/lib.rs
new file mode 100644
index 0000000..ec82d8e
--- /dev/null
+++ b/rand/rand_isaac/src/lib.rs
@@ -0,0 +1,36 @@
+// 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.
+
+//! The ISAAC and ISAAC-64 random number generators.
+
+#![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))))]
+
+#![cfg_attr(not(all(feature="serde1", test)), no_std)]
+
+extern crate rand_core;
+
+#[cfg(feature="serde1")] extern crate serde;
+#[cfg(feature="serde1")] #[macro_use] extern crate serde_derive;
+
+// To test serialization we need bincode and the standard library
+#[cfg(all(feature="serde1", test))] extern crate bincode;
+#[cfg(all(feature="serde1", test))] extern crate std as core;
+
+pub mod isaac;
+pub mod isaac64;
+
+mod isaac_array;
+
+pub use self::isaac::IsaacRng;
+pub use self::isaac64::Isaac64Rng;