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-rw-r--r--rand/rand_hc/src/hc128.rs462
-rw-r--r--rand/rand_hc/src/lib.rs25
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diff --git a/rand/rand_hc/src/hc128.rs b/rand/rand_hc/src/hc128.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.
+
+//! The HC-128 random number generator.
+
+use core::fmt;
+use rand_core::{CryptoRng, RngCore, SeedableRng, Error, le};
+use rand_core::block::{BlockRngCore, BlockRng};
+
+const SEED_WORDS: usize = 8; // 128 bit key followed by 128 bit iv
+
+/// A cryptographically secure random number generator that uses the HC-128
+/// algorithm.
+///
+/// HC-128 is a stream cipher designed by Hongjun Wu[^1], that we use as an
+/// RNG. It is selected as one of the "stream ciphers suitable for widespread
+/// adoption" by eSTREAM[^2].
+///
+/// HC-128 is an array based RNG. In this it is similar to RC-4 and ISAAC before
+/// it, but those have never been proven cryptographically secure (or have even
+/// been significantly compromised, as in the case of RC-4[^5]).
+///
+/// Because HC-128 works with simple indexing into a large array and with a few
+/// operations that parallelize well, it has very good performance. The size of
+/// the array it needs, 4kb, can however be a disadvantage.
+///
+/// This implementation is not based on the version of HC-128 submitted to the
+/// eSTREAM contest, but on a later version by the author with a few small
+/// improvements from December 15, 2009[^3].
+///
+/// HC-128 has no known weaknesses that are easier to exploit than doing a
+/// brute-force search of 2<sup>128</sup>. A very comprehensive analysis of the
+/// current state of known attacks / weaknesses of HC-128 is given in *Some
+/// Results On Analysis And Implementation Of HC-128 Stream Cipher*[^4].
+///
+/// The average cycle length is expected to be
+/// 2<sup>1024*32+10-1</sup> = 2<sup>32777</sup>.
+/// We support seeding with a 256-bit array, which matches the 128-bit key
+/// concatenated with a 128-bit IV from the stream cipher.
+///
+/// This implementation uses an output buffer of sixteen `u32` words, and uses
+/// [`BlockRng`] to implement the [`RngCore`] methods.
+///
+/// ## References
+/// [^1]: Hongjun Wu (2008). ["The Stream Cipher HC-128"](
+/// http://www.ecrypt.eu.org/stream/p3ciphers/hc/hc128_p3.pdf).
+/// *The eSTREAM Finalists*, LNCS 4986, pp. 39–47, Springer-Verlag.
+///
+/// [^2]: [eSTREAM: the ECRYPT Stream Cipher Project](
+/// http://www.ecrypt.eu.org/stream/)
+///
+/// [^3]: Hongjun Wu, [Stream Ciphers HC-128 and HC-256](
+/// https://www.ntu.edu.sg/home/wuhj/research/hc/index.html)
+///
+/// [^4]: Shashwat Raizada (January 2015),["Some Results On Analysis And
+/// Implementation Of HC-128 Stream Cipher"](
+/// http://library.isical.ac.in:8080/jspui/bitstream/123456789/6636/1/TH431.pdf).
+///
+/// [^5]: Internet Engineering Task Force (February 2015),
+/// ["Prohibiting RC4 Cipher Suites"](https://tools.ietf.org/html/rfc7465).
+///
+/// [`BlockRng`]: ../rand_core/block/struct.BlockRng.html
+/// [`RngCore`]: ../rand_core/trait.RngCore.html
+#[derive(Clone, Debug)]
+pub struct Hc128Rng(BlockRng<Hc128Core>);
+
+impl RngCore for Hc128Rng {
+ #[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 Hc128Rng {
+ type Seed = <Hc128Core as SeedableRng>::Seed;
+
+ fn from_seed(seed: Self::Seed) -> Self {
+ Hc128Rng(BlockRng::<Hc128Core>::from_seed(seed))
+ }
+
+ fn from_rng<R: RngCore>(rng: R) -> Result<Self, Error> {
+ BlockRng::<Hc128Core>::from_rng(rng).map(Hc128Rng)
+ }
+}
+
+impl CryptoRng for Hc128Rng {}
+
+/// The core of `Hc128Rng`, used with `BlockRng`.
+#[derive(Clone)]
+pub struct Hc128Core {
+ t: [u32; 1024],
+ counter1024: usize,
+}
+
+// Custom Debug implementation that does not expose the internal state
+impl fmt::Debug for Hc128Core {
+ fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+ write!(f, "Hc128Core {{}}")
+ }
+}
+
+impl BlockRngCore for Hc128Core {
+ type Item = u32;
+ type Results = [u32; 16];
+
+ fn generate(&mut self, results: &mut Self::Results) {
+ assert!(self.counter1024 % 16 == 0);
+
+ let cc = self.counter1024 % 512;
+ let dd = (cc + 16) % 512;
+ let ee = cc.wrapping_sub(16) % 512;
+
+ if self.counter1024 & 512 == 0 {
+ // P block
+ results[0] = self.step_p(cc+0, cc+1, ee+13, ee+6, ee+4);
+ results[1] = self.step_p(cc+1, cc+2, ee+14, ee+7, ee+5);
+ results[2] = self.step_p(cc+2, cc+3, ee+15, ee+8, ee+6);
+ results[3] = self.step_p(cc+3, cc+4, cc+0, ee+9, ee+7);
+ results[4] = self.step_p(cc+4, cc+5, cc+1, ee+10, ee+8);
+ results[5] = self.step_p(cc+5, cc+6, cc+2, ee+11, ee+9);
+ results[6] = self.step_p(cc+6, cc+7, cc+3, ee+12, ee+10);
+ results[7] = self.step_p(cc+7, cc+8, cc+4, ee+13, ee+11);
+ results[8] = self.step_p(cc+8, cc+9, cc+5, ee+14, ee+12);
+ results[9] = self.step_p(cc+9, cc+10, cc+6, ee+15, ee+13);
+ results[10] = self.step_p(cc+10, cc+11, cc+7, cc+0, ee+14);
+ results[11] = self.step_p(cc+11, cc+12, cc+8, cc+1, ee+15);
+ results[12] = self.step_p(cc+12, cc+13, cc+9, cc+2, cc+0);
+ results[13] = self.step_p(cc+13, cc+14, cc+10, cc+3, cc+1);
+ results[14] = self.step_p(cc+14, cc+15, cc+11, cc+4, cc+2);
+ results[15] = self.step_p(cc+15, dd+0, cc+12, cc+5, cc+3);
+ } else {
+ // Q block
+ results[0] = self.step_q(cc+0, cc+1, ee+13, ee+6, ee+4);
+ results[1] = self.step_q(cc+1, cc+2, ee+14, ee+7, ee+5);
+ results[2] = self.step_q(cc+2, cc+3, ee+15, ee+8, ee+6);
+ results[3] = self.step_q(cc+3, cc+4, cc+0, ee+9, ee+7);
+ results[4] = self.step_q(cc+4, cc+5, cc+1, ee+10, ee+8);
+ results[5] = self.step_q(cc+5, cc+6, cc+2, ee+11, ee+9);
+ results[6] = self.step_q(cc+6, cc+7, cc+3, ee+12, ee+10);
+ results[7] = self.step_q(cc+7, cc+8, cc+4, ee+13, ee+11);
+ results[8] = self.step_q(cc+8, cc+9, cc+5, ee+14, ee+12);
+ results[9] = self.step_q(cc+9, cc+10, cc+6, ee+15, ee+13);
+ results[10] = self.step_q(cc+10, cc+11, cc+7, cc+0, ee+14);
+ results[11] = self.step_q(cc+11, cc+12, cc+8, cc+1, ee+15);
+ results[12] = self.step_q(cc+12, cc+13, cc+9, cc+2, cc+0);
+ results[13] = self.step_q(cc+13, cc+14, cc+10, cc+3, cc+1);
+ results[14] = self.step_q(cc+14, cc+15, cc+11, cc+4, cc+2);
+ results[15] = self.step_q(cc+15, dd+0, cc+12, cc+5, cc+3);
+ }
+ self.counter1024 = self.counter1024.wrapping_add(16);
+ }
+}
+
+impl Hc128Core {
+ // One step of HC-128, update P and generate 32 bits keystream
+ #[inline(always)]
+ fn step_p(&mut self, i: usize, i511: usize, i3: usize, i10: usize, i12: usize)
+ -> u32
+ {
+ let (p, q) = self.t.split_at_mut(512);
+ // FIXME: it would be great if we the bounds checks here could be
+ // optimized out, and we would not need unsafe.
+ // This improves performance by about 7%.
+ unsafe {
+ let temp0 = p.get_unchecked(i511).rotate_right(23);
+ let temp1 = p.get_unchecked(i3).rotate_right(10);
+ let temp2 = p.get_unchecked(i10).rotate_right(8);
+ *p.get_unchecked_mut(i) = p.get_unchecked(i)
+ .wrapping_add(temp2)
+ .wrapping_add(temp0 ^ temp1);
+ let temp3 = {
+ // The h1 function in HC-128
+ let a = *p.get_unchecked(i12) as u8;
+ let c = (p.get_unchecked(i12) >> 16) as u8;
+ q[a as usize].wrapping_add(q[256 + c as usize])
+ };
+ temp3 ^ p.get_unchecked(i)
+ }
+ }
+
+ // One step of HC-128, update Q and generate 32 bits keystream
+ // Similar to `step_p`, but `p` and `q` are swapped, and the rotates are to
+ // the left instead of to the right.
+ #[inline(always)]
+ fn step_q(&mut self, i: usize, i511: usize, i3: usize, i10: usize, i12: usize)
+ -> u32
+ {
+ let (p, q) = self.t.split_at_mut(512);
+ unsafe {
+ let temp0 = q.get_unchecked(i511).rotate_left(23);
+ let temp1 = q.get_unchecked(i3).rotate_left(10);
+ let temp2 = q.get_unchecked(i10).rotate_left(8);
+ *q.get_unchecked_mut(i) = q.get_unchecked(i)
+ .wrapping_add(temp2)
+ .wrapping_add(temp0 ^ temp1);
+ let temp3 = {
+ // The h2 function in HC-128
+ let a = *q.get_unchecked(i12) as u8;
+ let c = (q.get_unchecked(i12) >> 16) as u8;
+ p[a as usize].wrapping_add(p[256 + c as usize])
+ };
+ temp3 ^ q.get_unchecked(i)
+ }
+ }
+
+ fn sixteen_steps(&mut self) {
+ assert!(self.counter1024 % 16 == 0);
+
+ let cc = self.counter1024 % 512;
+ let dd = (cc + 16) % 512;
+ let ee = cc.wrapping_sub(16) % 512;
+
+ if self.counter1024 < 512 {
+ // P block
+ self.t[cc+0] = self.step_p(cc+0, cc+1, ee+13, ee+6, ee+4);
+ self.t[cc+1] = self.step_p(cc+1, cc+2, ee+14, ee+7, ee+5);
+ self.t[cc+2] = self.step_p(cc+2, cc+3, ee+15, ee+8, ee+6);
+ self.t[cc+3] = self.step_p(cc+3, cc+4, cc+0, ee+9, ee+7);
+ self.t[cc+4] = self.step_p(cc+4, cc+5, cc+1, ee+10, ee+8);
+ self.t[cc+5] = self.step_p(cc+5, cc+6, cc+2, ee+11, ee+9);
+ self.t[cc+6] = self.step_p(cc+6, cc+7, cc+3, ee+12, ee+10);
+ self.t[cc+7] = self.step_p(cc+7, cc+8, cc+4, ee+13, ee+11);
+ self.t[cc+8] = self.step_p(cc+8, cc+9, cc+5, ee+14, ee+12);
+ self.t[cc+9] = self.step_p(cc+9, cc+10, cc+6, ee+15, ee+13);
+ self.t[cc+10] = self.step_p(cc+10, cc+11, cc+7, cc+0, ee+14);
+ self.t[cc+11] = self.step_p(cc+11, cc+12, cc+8, cc+1, ee+15);
+ self.t[cc+12] = self.step_p(cc+12, cc+13, cc+9, cc+2, cc+0);
+ self.t[cc+13] = self.step_p(cc+13, cc+14, cc+10, cc+3, cc+1);
+ self.t[cc+14] = self.step_p(cc+14, cc+15, cc+11, cc+4, cc+2);
+ self.t[cc+15] = self.step_p(cc+15, dd+0, cc+12, cc+5, cc+3);
+ } else {
+ // Q block
+ self.t[cc+512+0] = self.step_q(cc+0, cc+1, ee+13, ee+6, ee+4);
+ self.t[cc+512+1] = self.step_q(cc+1, cc+2, ee+14, ee+7, ee+5);
+ self.t[cc+512+2] = self.step_q(cc+2, cc+3, ee+15, ee+8, ee+6);
+ self.t[cc+512+3] = self.step_q(cc+3, cc+4, cc+0, ee+9, ee+7);
+ self.t[cc+512+4] = self.step_q(cc+4, cc+5, cc+1, ee+10, ee+8);
+ self.t[cc+512+5] = self.step_q(cc+5, cc+6, cc+2, ee+11, ee+9);
+ self.t[cc+512+6] = self.step_q(cc+6, cc+7, cc+3, ee+12, ee+10);
+ self.t[cc+512+7] = self.step_q(cc+7, cc+8, cc+4, ee+13, ee+11);
+ self.t[cc+512+8] = self.step_q(cc+8, cc+9, cc+5, ee+14, ee+12);
+ self.t[cc+512+9] = self.step_q(cc+9, cc+10, cc+6, ee+15, ee+13);
+ self.t[cc+512+10] = self.step_q(cc+10, cc+11, cc+7, cc+0, ee+14);
+ self.t[cc+512+11] = self.step_q(cc+11, cc+12, cc+8, cc+1, ee+15);
+ self.t[cc+512+12] = self.step_q(cc+12, cc+13, cc+9, cc+2, cc+0);
+ self.t[cc+512+13] = self.step_q(cc+13, cc+14, cc+10, cc+3, cc+1);
+ self.t[cc+512+14] = self.step_q(cc+14, cc+15, cc+11, cc+4, cc+2);
+ self.t[cc+512+15] = self.step_q(cc+15, dd+0, cc+12, cc+5, cc+3);
+ }
+ self.counter1024 += 16;
+ }
+
+ // Initialize an HC-128 random number generator. The seed has to be
+ // 256 bits in length (`[u32; 8]`), matching the 128 bit `key` followed by
+ // 128 bit `iv` when HC-128 where to be used as a stream cipher.
+ fn init(seed: [u32; SEED_WORDS]) -> Self {
+ #[inline]
+ fn f1(x: u32) -> u32 {
+ x.rotate_right(7) ^ x.rotate_right(18) ^ (x >> 3)
+ }
+
+ #[inline]
+ fn f2(x: u32) -> u32 {
+ x.rotate_right(17) ^ x.rotate_right(19) ^ (x >> 10)
+ }
+
+ let mut t = [0u32; 1024];
+
+ // Expand the key and iv into P and Q
+ let (key, iv) = seed.split_at(4);
+ t[..4].copy_from_slice(key);
+ t[4..8].copy_from_slice(key);
+ t[8..12].copy_from_slice(iv);
+ t[12..16].copy_from_slice(iv);
+
+ // Generate the 256 intermediate values W[16] ... W[256+16-1], and
+ // copy the last 16 generated values to the start op P.
+ for i in 16..256+16 {
+ t[i] = f2(t[i-2]).wrapping_add(t[i-7]).wrapping_add(f1(t[i-15]))
+ .wrapping_add(t[i-16]).wrapping_add(i as u32);
+ }
+ {
+ let (p1, p2) = t.split_at_mut(256);
+ p1[0..16].copy_from_slice(&p2[0..16]);
+ }
+
+ // Generate both the P and Q tables
+ for i in 16..1024 {
+ t[i] = f2(t[i-2]).wrapping_add(t[i-7]).wrapping_add(f1(t[i-15]))
+ .wrapping_add(t[i-16]).wrapping_add(256 + i as u32);
+ }
+
+ let mut core = Self { t, counter1024: 0 };
+
+ // run the cipher 1024 steps
+ for _ in 0..64 { core.sixteen_steps() };
+ core.counter1024 = 0;
+ core
+ }
+}
+
+impl SeedableRng for Hc128Core {
+ type Seed = [u8; SEED_WORDS*4];
+
+ /// Create an HC-128 random number generator with a seed. The seed has to be
+ /// 256 bits in length, matching the 128 bit `key` followed by 128 bit `iv`
+ /// when HC-128 where to be used as a stream cipher.
+ fn from_seed(seed: Self::Seed) -> Self {
+ let mut seed_u32 = [0u32; SEED_WORDS];
+ le::read_u32_into(&seed, &mut seed_u32);
+ Self::init(seed_u32)
+ }
+}
+
+impl CryptoRng for Hc128Core {}
+
+#[cfg(test)]
+mod test {
+ use ::rand_core::{RngCore, SeedableRng};
+ use super::Hc128Rng;
+
+ #[test]
+ // Test vector 1 from the paper "The Stream Cipher HC-128"
+ fn test_hc128_true_values_a() {
+ let seed = [0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0, // key
+ 0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0]; // iv
+ let mut rng = Hc128Rng::from_seed(seed);
+
+ let mut results = [0u32; 16];
+ for i in results.iter_mut() { *i = rng.next_u32(); }
+ let expected = [0x73150082, 0x3bfd03a0, 0xfb2fd77f, 0xaa63af0e,
+ 0xde122fc6, 0xa7dc29b6, 0x62a68527, 0x8b75ec68,
+ 0x9036db1e, 0x81896005, 0x00ade078, 0x491fbf9a,
+ 0x1cdc3013, 0x6c3d6e24, 0x90f664b2, 0x9cd57102];
+ assert_eq!(results, expected);
+ }
+
+ #[test]
+ // Test vector 2 from the paper "The Stream Cipher HC-128"
+ fn test_hc128_true_values_b() {
+ let seed = [0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0, // key
+ 1,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0]; // iv
+ let mut rng = Hc128Rng::from_seed(seed);
+
+ let mut results = [0u32; 16];
+ for i in results.iter_mut() { *i = rng.next_u32(); }
+ let expected = [0xc01893d5, 0xb7dbe958, 0x8f65ec98, 0x64176604,
+ 0x36fc6724, 0xc82c6eec, 0x1b1c38a7, 0xc9b42a95,
+ 0x323ef123, 0x0a6a908b, 0xce757b68, 0x9f14f7bb,
+ 0xe4cde011, 0xaeb5173f, 0x89608c94, 0xb5cf46ca];
+ assert_eq!(results, expected);
+ }
+
+ #[test]
+ // Test vector 3 from the paper "The Stream Cipher HC-128"
+ fn test_hc128_true_values_c() {
+ let seed = [0x55,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0, // key
+ 0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0]; // iv
+ let mut rng = Hc128Rng::from_seed(seed);
+
+ let mut results = [0u32; 16];
+ for i in results.iter_mut() { *i = rng.next_u32(); }
+ let expected = [0x518251a4, 0x04b4930a, 0xb02af931, 0x0639f032,
+ 0xbcb4a47a, 0x5722480b, 0x2bf99f72, 0xcdc0e566,
+ 0x310f0c56, 0xd3cc83e8, 0x663db8ef, 0x62dfe07f,
+ 0x593e1790, 0xc5ceaa9c, 0xab03806f, 0xc9a6e5a0];
+ assert_eq!(results, expected);
+ }
+
+ #[test]
+ fn test_hc128_true_values_u64() {
+ let seed = [0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0, // key
+ 0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0]; // iv
+ let mut rng = Hc128Rng::from_seed(seed);
+
+ let mut results = [0u64; 8];
+ for i in results.iter_mut() { *i = rng.next_u64(); }
+ let expected = [0x3bfd03a073150082, 0xaa63af0efb2fd77f,
+ 0xa7dc29b6de122fc6, 0x8b75ec6862a68527,
+ 0x818960059036db1e, 0x491fbf9a00ade078,
+ 0x6c3d6e241cdc3013, 0x9cd5710290f664b2];
+ assert_eq!(results, expected);
+
+ // The RNG operates in a P block of 512 results and next a Q block.
+ // After skipping 2*800 u32 results we end up somewhere in the Q block
+ // of the second round
+ for _ in 0..800 { rng.next_u64(); }
+
+ for i in results.iter_mut() { *i = rng.next_u64(); }
+ let expected = [0xd8c4d6ca84d0fc10, 0xf16a5d91dc66e8e7,
+ 0xd800de5bc37a8653, 0x7bae1f88c0dfbb4c,
+ 0x3bfe1f374e6d4d14, 0x424b55676be3fa06,
+ 0xe3a1e8758cbff579, 0x417f7198c5652bcd];
+ assert_eq!(results, expected);
+ }
+
+ #[test]
+ fn test_hc128_true_values_bytes() {
+ let seed = [0x55,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0, // key
+ 0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0]; // iv
+ let mut rng = Hc128Rng::from_seed(seed);
+ let expected = [0x31, 0xf9, 0x2a, 0xb0, 0x32, 0xf0, 0x39, 0x06,
+ 0x7a, 0xa4, 0xb4, 0xbc, 0x0b, 0x48, 0x22, 0x57,
+ 0x72, 0x9f, 0xf9, 0x2b, 0x66, 0xe5, 0xc0, 0xcd,
+ 0x56, 0x0c, 0x0f, 0x31, 0xe8, 0x83, 0xcc, 0xd3,
+ 0xef, 0xb8, 0x3d, 0x66, 0x7f, 0xe0, 0xdf, 0x62,
+ 0x90, 0x17, 0x3e, 0x59, 0x9c, 0xaa, 0xce, 0xc5,
+ 0x6f, 0x80, 0x03, 0xab, 0xa0, 0xe5, 0xa6, 0xc9,
+ 0x60, 0x95, 0x84, 0x7a, 0xa5, 0x68, 0x5a, 0x84,
+ 0xea, 0xd5, 0xf3, 0xea, 0x73, 0xa9, 0xad, 0x01,
+ 0x79, 0x7d, 0xbe, 0x9f, 0xea, 0xe3, 0xf9, 0x74,
+ 0x0e, 0xda, 0x2f, 0xa0, 0xe4, 0x7b, 0x4b, 0x1b,
+ 0xdd, 0x17, 0x69, 0x4a, 0xfe, 0x9f, 0x56, 0x95,
+ 0xad, 0x83, 0x6b, 0x9d, 0x60, 0xa1, 0x99, 0x96,
+ 0x90, 0x00, 0x66, 0x7f, 0xfa, 0x7e, 0x65, 0xe9,
+ 0xac, 0x8b, 0x92, 0x34, 0x77, 0xb4, 0x23, 0xd0,
+ 0xb9, 0xab, 0xb1, 0x47, 0x7d, 0x4a, 0x13, 0x0a];
+
+ // Pick a somewhat large buffer so we can test filling with the
+ // remainder from `state.results`, directly filling the buffer, and
+ // filling the remainder of the buffer.
+ let mut buffer = [0u8; 16*4*2];
+ // Consume a value so that we have a remainder.
+ assert!(rng.next_u64() == 0x04b4930a518251a4);
+ rng.fill_bytes(&mut buffer);
+
+ // [u8; 128] doesn't implement PartialEq
+ assert_eq!(buffer.len(), expected.len());
+ for (b, e) in buffer.iter().zip(expected.iter()) {
+ assert_eq!(b, e);
+ }
+ }
+
+ #[test]
+ fn test_hc128_clone() {
+ let seed = [0x55,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0, // key
+ 0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0]; // iv
+ let mut rng1 = Hc128Rng::from_seed(seed);
+ let mut rng2 = rng1.clone();
+ for _ in 0..16 {
+ assert_eq!(rng1.next_u32(), rng2.next_u32());
+ }
+ }
+}
diff --git a/rand/rand_hc/src/lib.rs b/rand/rand_hc/src/lib.rs
new file mode 100644
index 0000000..f1d772d
--- /dev/null
+++ b/rand/rand_hc/src/lib.rs
@@ -0,0 +1,25 @@
+// 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 HC128 random number generator.
+
+#![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))))]
+
+#![no_std]
+
+extern crate rand_core;
+
+mod hc128;
+
+pub use hc128::{Hc128Rng, Hc128Core};
generated by cgit v1.2.3 (git 2.46.0) at 2025-10-31 13:10:18 +0000