diff options
Diffstat (limited to 'rand/src/prng')
-rw-r--r-- | rand/src/prng/chacha.rs | 321 | ||||
-rw-r--r-- | rand/src/prng/isaac.rs | 328 | ||||
-rw-r--r-- | rand/src/prng/isaac64.rs | 340 | ||||
-rw-r--r-- | rand/src/prng/mod.rs | 74 | ||||
-rw-r--r-- | rand/src/prng/xorshift.rs | 101 |
5 files changed, 30 insertions, 1134 deletions
diff --git a/rand/src/prng/chacha.rs b/rand/src/prng/chacha.rs deleted file mode 100644 index a73e8e7..0000000 --- a/rand/src/prng/chacha.rs +++ /dev/null @@ -1,321 +0,0 @@ -// Copyright 2014 The Rust Project Developers. See the COPYRIGHT -// file at the top-level directory of this distribution and at -// http://rust-lang.org/COPYRIGHT. -// -// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or -// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license -// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your -// option. This file may not be copied, modified, or distributed -// except according to those terms. - -//! The ChaCha random number generator. - -use core::num::Wrapping as w; -use {Rng, SeedableRng, Rand}; - -#[allow(bad_style)] -type w32 = w<u32>; - -const KEY_WORDS : usize = 8; // 8 words for the 256-bit key -const STATE_WORDS : usize = 16; -const CHACHA_ROUNDS: u32 = 20; // Cryptographically secure from 8 upwards as of this writing - -/// A random number generator that uses the ChaCha20 algorithm [1]. -/// -/// The ChaCha algorithm is widely accepted as suitable for -/// cryptographic purposes, but this implementation has not been -/// verified as such. Prefer a generator like `OsRng` that defers to -/// the operating system for cases that need high security. -/// -/// [1]: D. J. Bernstein, [*ChaCha, a variant of -/// Salsa20*](http://cr.yp.to/chacha.html) -#[derive(Copy, Clone, Debug)] -pub struct ChaChaRng { - buffer: [w32; STATE_WORDS], // Internal buffer of output - state: [w32; STATE_WORDS], // Initial state - index: usize, // Index into state -} - -static EMPTY: ChaChaRng = ChaChaRng { - buffer: [w(0); STATE_WORDS], - state: [w(0); STATE_WORDS], - index: STATE_WORDS -}; - - -macro_rules! quarter_round{ - ($a: expr, $b: expr, $c: expr, $d: expr) => {{ - $a = $a + $b; $d = $d ^ $a; $d = w($d.0.rotate_left(16)); - $c = $c + $d; $b = $b ^ $c; $b = w($b.0.rotate_left(12)); - $a = $a + $b; $d = $d ^ $a; $d = w($d.0.rotate_left( 8)); - $c = $c + $d; $b = $b ^ $c; $b = w($b.0.rotate_left( 7)); - }} -} - -macro_rules! double_round{ - ($x: expr) => {{ - // Column round - quarter_round!($x[ 0], $x[ 4], $x[ 8], $x[12]); - quarter_round!($x[ 1], $x[ 5], $x[ 9], $x[13]); - quarter_round!($x[ 2], $x[ 6], $x[10], $x[14]); - quarter_round!($x[ 3], $x[ 7], $x[11], $x[15]); - // Diagonal round - quarter_round!($x[ 0], $x[ 5], $x[10], $x[15]); - quarter_round!($x[ 1], $x[ 6], $x[11], $x[12]); - quarter_round!($x[ 2], $x[ 7], $x[ 8], $x[13]); - quarter_round!($x[ 3], $x[ 4], $x[ 9], $x[14]); - }} -} - -#[inline] -fn core(output: &mut [w32; STATE_WORDS], input: &[w32; STATE_WORDS]) { - *output = *input; - - for _ in 0..CHACHA_ROUNDS / 2 { - double_round!(output); - } - - for i in 0..STATE_WORDS { - output[i] = output[i] + input[i]; - } -} - -impl ChaChaRng { - - /// Create an ChaCha random number generator using the default - /// fixed key of 8 zero words. - /// - /// # Examples - /// - /// ```rust - /// use rand::{Rng, ChaChaRng}; - /// - /// let mut ra = ChaChaRng::new_unseeded(); - /// println!("{:?}", ra.next_u32()); - /// println!("{:?}", ra.next_u32()); - /// ``` - /// - /// Since this equivalent to a RNG with a fixed seed, repeated executions - /// of an unseeded RNG will produce the same result. This code sample will - /// consistently produce: - /// - /// - 2917185654 - /// - 2419978656 - pub fn new_unseeded() -> ChaChaRng { - let mut rng = EMPTY; - rng.init(&[0; KEY_WORDS]); - rng - } - - /// Sets the internal 128-bit ChaCha counter to - /// a user-provided value. This permits jumping - /// arbitrarily ahead (or backwards) in the pseudorandom stream. - /// - /// Since the nonce words are used to extend the counter to 128 bits, - /// users wishing to obtain the conventional ChaCha pseudorandom stream - /// associated with a particular nonce can call this function with - /// arguments `0, desired_nonce`. - /// - /// # Examples - /// - /// ```rust - /// use rand::{Rng, ChaChaRng}; - /// - /// let mut ra = ChaChaRng::new_unseeded(); - /// ra.set_counter(0u64, 1234567890u64); - /// println!("{:?}", ra.next_u32()); - /// println!("{:?}", ra.next_u32()); - /// ``` - pub fn set_counter(&mut self, counter_low: u64, counter_high: u64) { - self.state[12] = w((counter_low >> 0) as u32); - self.state[13] = w((counter_low >> 32) as u32); - self.state[14] = w((counter_high >> 0) as u32); - self.state[15] = w((counter_high >> 32) as u32); - self.index = STATE_WORDS; // force recomputation - } - - /// Initializes `self.state` with the appropriate key and constants - /// - /// We deviate slightly from the ChaCha specification regarding - /// the nonce, which is used to extend the counter to 128 bits. - /// This is provably as strong as the original cipher, though, - /// since any distinguishing attack on our variant also works - /// against ChaCha with a chosen-nonce. See the XSalsa20 [1] - /// security proof for a more involved example of this. - /// - /// The modified word layout is: - /// ```text - /// constant constant constant constant - /// key key key key - /// key key key key - /// counter counter counter counter - /// ``` - /// [1]: Daniel J. Bernstein. [*Extending the Salsa20 - /// nonce.*](http://cr.yp.to/papers.html#xsalsa) - fn init(&mut self, key: &[u32; KEY_WORDS]) { - self.state[0] = w(0x61707865); - self.state[1] = w(0x3320646E); - self.state[2] = w(0x79622D32); - self.state[3] = w(0x6B206574); - - for i in 0..KEY_WORDS { - self.state[4+i] = w(key[i]); - } - - self.state[12] = w(0); - self.state[13] = w(0); - self.state[14] = w(0); - self.state[15] = w(0); - - self.index = STATE_WORDS; - } - - /// Refill the internal output buffer (`self.buffer`) - fn update(&mut self) { - core(&mut self.buffer, &self.state); - self.index = 0; - // update 128-bit counter - self.state[12] = self.state[12] + w(1); - if self.state[12] != w(0) { return }; - self.state[13] = self.state[13] + w(1); - if self.state[13] != w(0) { return }; - self.state[14] = self.state[14] + w(1); - if self.state[14] != w(0) { return }; - self.state[15] = self.state[15] + w(1); - } -} - -impl Rng for ChaChaRng { - #[inline] - fn next_u32(&mut self) -> u32 { - if self.index == STATE_WORDS { - self.update(); - } - - let value = self.buffer[self.index % STATE_WORDS]; - self.index += 1; - value.0 - } -} - -impl<'a> SeedableRng<&'a [u32]> for ChaChaRng { - - fn reseed(&mut self, seed: &'a [u32]) { - // reset state - self.init(&[0u32; KEY_WORDS]); - // set key in place - let key = &mut self.state[4 .. 4+KEY_WORDS]; - for (k, s) in key.iter_mut().zip(seed.iter()) { - *k = w(*s); - } - } - - /// Create a ChaCha generator from a seed, - /// obtained from a variable-length u32 array. - /// Only up to 8 words are used; if less than 8 - /// words are used, the remaining are set to zero. - fn from_seed(seed: &'a [u32]) -> ChaChaRng { - let mut rng = EMPTY; - rng.reseed(seed); - rng - } -} - -impl Rand for ChaChaRng { - fn rand<R: Rng>(other: &mut R) -> ChaChaRng { - let mut key : [u32; KEY_WORDS] = [0; KEY_WORDS]; - for word in key.iter_mut() { - *word = other.gen(); - } - SeedableRng::from_seed(&key[..]) - } -} - - -#[cfg(test)] -mod test { - use {Rng, SeedableRng}; - use super::ChaChaRng; - - #[test] - fn test_rng_rand_seeded() { - let s = ::test::rng().gen_iter::<u32>().take(8).collect::<Vec<u32>>(); - let mut ra: ChaChaRng = SeedableRng::from_seed(&s[..]); - let mut rb: ChaChaRng = SeedableRng::from_seed(&s[..]); - assert!(::test::iter_eq(ra.gen_ascii_chars().take(100), - rb.gen_ascii_chars().take(100))); - } - - #[test] - fn test_rng_seeded() { - let seed : &[_] = &[0,1,2,3,4,5,6,7]; - let mut ra: ChaChaRng = SeedableRng::from_seed(seed); - let mut rb: ChaChaRng = SeedableRng::from_seed(seed); - assert!(::test::iter_eq(ra.gen_ascii_chars().take(100), - rb.gen_ascii_chars().take(100))); - } - - #[test] - fn test_rng_reseed() { - let s = ::test::rng().gen_iter::<u32>().take(8).collect::<Vec<u32>>(); - let mut r: ChaChaRng = SeedableRng::from_seed(&s[..]); - let string1: String = r.gen_ascii_chars().take(100).collect(); - - r.reseed(&s); - - let string2: String = r.gen_ascii_chars().take(100).collect(); - assert_eq!(string1, string2); - } - - #[test] - fn test_rng_true_values() { - // Test vectors 1 and 2 from - // http://tools.ietf.org/html/draft-nir-cfrg-chacha20-poly1305-04 - let seed : &[_] = &[0u32; 8]; - let mut ra: ChaChaRng = SeedableRng::from_seed(seed); - - let v = (0..16).map(|_| ra.next_u32()).collect::<Vec<_>>(); - assert_eq!(v, - vec!(0xade0b876, 0x903df1a0, 0xe56a5d40, 0x28bd8653, - 0xb819d2bd, 0x1aed8da0, 0xccef36a8, 0xc70d778b, - 0x7c5941da, 0x8d485751, 0x3fe02477, 0x374ad8b8, - 0xf4b8436a, 0x1ca11815, 0x69b687c3, 0x8665eeb2)); - - let v = (0..16).map(|_| ra.next_u32()).collect::<Vec<_>>(); - assert_eq!(v, - vec!(0xbee7079f, 0x7a385155, 0x7c97ba98, 0x0d082d73, - 0xa0290fcb, 0x6965e348, 0x3e53c612, 0xed7aee32, - 0x7621b729, 0x434ee69c, 0xb03371d5, 0xd539d874, - 0x281fed31, 0x45fb0a51, 0x1f0ae1ac, 0x6f4d794b)); - - - let seed : &[_] = &[0,1,2,3,4,5,6,7]; - let mut ra: ChaChaRng = SeedableRng::from_seed(seed); - - // Store the 17*i-th 32-bit word, - // i.e., the i-th word of the i-th 16-word block - let mut v : Vec<u32> = Vec::new(); - for _ in 0..16 { - v.push(ra.next_u32()); - for _ in 0..16 { - ra.next_u32(); - } - } - - assert_eq!(v, - vec!(0xf225c81a, 0x6ab1be57, 0x04d42951, 0x70858036, - 0x49884684, 0x64efec72, 0x4be2d186, 0x3615b384, - 0x11cfa18e, 0xd3c50049, 0x75c775f6, 0x434c6530, - 0x2c5bad8f, 0x898881dc, 0x5f1c86d9, 0xc1f8e7f4)); - } - - #[test] - fn test_rng_clone() { - let seed : &[_] = &[0u32; 8]; - let mut rng: ChaChaRng = SeedableRng::from_seed(seed); - let mut clone = rng.clone(); - for _ in 0..16 { - assert_eq!(rng.next_u64(), clone.next_u64()); - } - } -} diff --git a/rand/src/prng/isaac.rs b/rand/src/prng/isaac.rs deleted file mode 100644 index cf5eb67..0000000 --- a/rand/src/prng/isaac.rs +++ /dev/null @@ -1,328 +0,0 @@ -// Copyright 2013 The Rust Project Developers. See the COPYRIGHT -// file at the top-level directory of this distribution and at -// http://rust-lang.org/COPYRIGHT. -// -// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or -// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license -// <LICENSE-MIT or http://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. - -#![allow(non_camel_case_types)] - -use core::slice; -use core::iter::repeat; -use core::num::Wrapping as w; -use core::fmt; - -use {Rng, SeedableRng, Rand}; - -#[allow(bad_style)] -type w32 = w<u32>; - -const RAND_SIZE_LEN: usize = 8; -const RAND_SIZE: u32 = 1 << RAND_SIZE_LEN; -const RAND_SIZE_USIZE: usize = 1 << RAND_SIZE_LEN; - -/// A random number generator that uses the ISAAC algorithm[1]. -/// -/// The ISAAC algorithm is generally accepted as suitable for -/// cryptographic purposes, but this implementation has not be -/// verified as such. Prefer a generator like `OsRng` that defers to -/// the operating system for cases that need high security. -/// -/// [1]: Bob Jenkins, [*ISAAC: A fast cryptographic random number -/// generator*](http://www.burtleburtle.net/bob/rand/isaacafa.html) -#[derive(Copy)] -pub struct IsaacRng { - cnt: u32, - rsl: [w32; RAND_SIZE_USIZE], - mem: [w32; RAND_SIZE_USIZE], - a: w32, - b: w32, - c: w32, -} - -static EMPTY: IsaacRng = IsaacRng { - cnt: 0, - rsl: [w(0); RAND_SIZE_USIZE], - mem: [w(0); RAND_SIZE_USIZE], - a: w(0), b: w(0), c: w(0), -}; - -impl IsaacRng { - - /// Create an ISAAC random number generator using the default - /// fixed seed. - pub fn new_unseeded() -> IsaacRng { - let mut rng = EMPTY; - rng.init(false); - rng - } - - /// Initialises `self`. If `use_rsl` is true, then use the current value - /// of `rsl` as a seed, otherwise construct one algorithmically (not - /// randomly). - fn init(&mut self, use_rsl: bool) { - let mut a = w(0x9e3779b9); - let mut b = a; - let mut c = a; - let mut d = a; - let mut e = a; - let mut f = a; - let mut g = a; - let mut h = a; - - macro_rules! mix { - () => {{ - a=a^(b<<11); d=d+a; b=b+c; - b=b^(c>>2); e=e+b; c=c+d; - c=c^(d<<8); f=f+c; d=d+e; - d=d^(e>>16); g=g+d; e=e+f; - e=e^(f<<10); h=h+e; f=f+g; - f=f^(g>>4); a=a+f; g=g+h; - g=g^(h<<8); b=b+g; h=h+a; - h=h^(a>>9); c=c+h; a=a+b; - }} - } - - for _ in 0..4 { - mix!(); - } - - if use_rsl { - macro_rules! memloop { - ($arr:expr) => {{ - for i in (0..RAND_SIZE_USIZE/8).map(|i| i * 8) { - a=a+$arr[i ]; b=b+$arr[i+1]; - c=c+$arr[i+2]; d=d+$arr[i+3]; - e=e+$arr[i+4]; f=f+$arr[i+5]; - g=g+$arr[i+6]; h=h+$arr[i+7]; - mix!(); - self.mem[i ]=a; self.mem[i+1]=b; - self.mem[i+2]=c; self.mem[i+3]=d; - self.mem[i+4]=e; self.mem[i+5]=f; - self.mem[i+6]=g; self.mem[i+7]=h; - } - }} - } - - memloop!(self.rsl); - memloop!(self.mem); - } else { - for i in (0..RAND_SIZE_USIZE/8).map(|i| i * 8) { - mix!(); - self.mem[i ]=a; self.mem[i+1]=b; - self.mem[i+2]=c; self.mem[i+3]=d; - self.mem[i+4]=e; self.mem[i+5]=f; - self.mem[i+6]=g; self.mem[i+7]=h; - } - } - - self.isaac(); - } - - /// Refills the output buffer (`self.rsl`) - #[inline] - fn isaac(&mut self) { - self.c = self.c + w(1); - // abbreviations - let mut a = self.a; - let mut b = self.b + self.c; - - const MIDPOINT: usize = RAND_SIZE_USIZE / 2; - - macro_rules! ind { - ($x:expr) => ( self.mem[($x >> 2usize).0 as usize & (RAND_SIZE_USIZE - 1)] ) - } - - let r = [(0, MIDPOINT), (MIDPOINT, 0)]; - for &(mr_offset, m2_offset) in r.iter() { - - macro_rules! rngstepp { - ($j:expr, $shift:expr) => {{ - let base = $j; - let mix = a << $shift; - - let x = self.mem[base + mr_offset]; - a = (a ^ mix) + self.mem[base + m2_offset]; - let y = ind!(x) + a + b; - self.mem[base + mr_offset] = y; - - b = ind!(y >> RAND_SIZE_LEN) + x; - self.rsl[base + mr_offset] = b; - }} - } - - macro_rules! rngstepn { - ($j:expr, $shift:expr) => {{ - let base = $j; - let mix = a >> $shift; - - let x = self.mem[base + mr_offset]; - a = (a ^ mix) + self.mem[base + m2_offset]; - let y = ind!(x) + a + b; - self.mem[base + mr_offset] = y; - - b = ind!(y >> RAND_SIZE_LEN) + x; - self.rsl[base + mr_offset] = b; - }} - } - - for i in (0..MIDPOINT/4).map(|i| i * 4) { - rngstepp!(i + 0, 13); - rngstepn!(i + 1, 6); - rngstepp!(i + 2, 2); - rngstepn!(i + 3, 16); - } - } - - self.a = a; - self.b = b; - self.cnt = RAND_SIZE; - } -} - -// Cannot be derived because [u32; 256] does not implement Clone -impl Clone for IsaacRng { - fn clone(&self) -> IsaacRng { - *self - } -} - -impl Rng for IsaacRng { - #[inline] - fn next_u32(&mut self) -> u32 { - if self.cnt == 0 { - // make some more numbers - self.isaac(); - } - self.cnt -= 1; - - // self.cnt is at most RAND_SIZE, but that is before the - // subtraction above. We want to index without bounds - // checking, but this could lead to incorrect code if someone - // misrefactors, so we check, sometimes. - // - // (Changes here should be reflected in Isaac64Rng.next_u64.) - debug_assert!(self.cnt < RAND_SIZE); - - // (the % is cheaply telling the optimiser that we're always - // in bounds, without unsafe. NB. this is a power of two, so - // it optimises to a bitwise mask). - self.rsl[(self.cnt % RAND_SIZE) as usize].0 - } -} - -impl<'a> SeedableRng<&'a [u32]> for IsaacRng { - fn reseed(&mut self, seed: &'a [u32]) { - // make the seed into [seed[0], seed[1], ..., seed[seed.len() - // - 1], 0, 0, ...], to fill rng.rsl. - let seed_iter = seed.iter().map(|&x| x).chain(repeat(0u32)); - - for (rsl_elem, seed_elem) in self.rsl.iter_mut().zip(seed_iter) { - *rsl_elem = w(seed_elem); - } - self.cnt = 0; - self.a = w(0); - self.b = w(0); - self.c = w(0); - - self.init(true); - } - - /// Create an ISAAC random number generator with a seed. This can - /// be any length, although the maximum number of elements used is - /// 256 and any more will be silently ignored. A generator - /// constructed with a given seed will generate the same sequence - /// of values as all other generators constructed with that seed. - fn from_seed(seed: &'a [u32]) -> IsaacRng { - let mut rng = EMPTY; - rng.reseed(seed); - rng - } -} - -impl Rand for IsaacRng { - fn rand<R: Rng>(other: &mut R) -> IsaacRng { - let mut ret = EMPTY; - unsafe { - let ptr = ret.rsl.as_mut_ptr() as *mut u8; - - let slice = slice::from_raw_parts_mut(ptr, RAND_SIZE_USIZE * 4); - other.fill_bytes(slice); - } - ret.cnt = 0; - ret.a = w(0); - ret.b = w(0); - ret.c = w(0); - - ret.init(true); - return ret; - } -} - -impl fmt::Debug for IsaacRng { - fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { - write!(f, "IsaacRng {{}}") - } -} - -#[cfg(test)] -mod test { - use {Rng, SeedableRng}; - use super::IsaacRng; - - #[test] - fn test_rng_32_rand_seeded() { - let s = ::test::rng().gen_iter::<u32>().take(256).collect::<Vec<u32>>(); - let mut ra: IsaacRng = SeedableRng::from_seed(&s[..]); - let mut rb: IsaacRng = SeedableRng::from_seed(&s[..]); - assert!(::test::iter_eq(ra.gen_ascii_chars().take(100), - rb.gen_ascii_chars().take(100))); - } - - #[test] - fn test_rng_32_seeded() { - let seed: &[_] = &[1, 23, 456, 7890, 12345]; - let mut ra: IsaacRng = SeedableRng::from_seed(seed); - let mut rb: IsaacRng = SeedableRng::from_seed(seed); - assert!(::test::iter_eq(ra.gen_ascii_chars().take(100), - rb.gen_ascii_chars().take(100))); - } - - #[test] - fn test_rng_32_reseed() { - let s = ::test::rng().gen_iter::<u32>().take(256).collect::<Vec<u32>>(); - let mut r: IsaacRng = SeedableRng::from_seed(&s[..]); - let string1: String = r.gen_ascii_chars().take(100).collect(); - - r.reseed(&s[..]); - - let string2: String = r.gen_ascii_chars().take(100).collect(); - assert_eq!(string1, string2); - } - - #[test] - fn test_rng_32_true_values() { - let seed: &[_] = &[1, 23, 456, 7890, 12345]; - let mut ra: IsaacRng = SeedableRng::from_seed(seed); - // Regression test that isaac is actually using the above vector - let v = (0..10).map(|_| ra.next_u32()).collect::<Vec<_>>(); - assert_eq!(v, - vec!(2558573138, 873787463, 263499565, 2103644246, 3595684709, - 4203127393, 264982119, 2765226902, 2737944514, 3900253796)); - - let seed: &[_] = &[12345, 67890, 54321, 9876]; - let mut rb: IsaacRng = SeedableRng::from_seed(seed); - // skip forward to the 10000th number - for _ in 0..10000 { rb.next_u32(); } - - let v = (0..10).map(|_| rb.next_u32()).collect::<Vec<_>>(); - assert_eq!(v, - vec!(3676831399, 3183332890, 2834741178, 3854698763, 2717568474, - 1576568959, 3507990155, 179069555, 141456972, 2478885421)); - } -} diff --git a/rand/src/prng/isaac64.rs b/rand/src/prng/isaac64.rs deleted file mode 100644 index b98e3fe..0000000 --- a/rand/src/prng/isaac64.rs +++ /dev/null @@ -1,340 +0,0 @@ -// Copyright 2013 The Rust Project Developers. See the COPYRIGHT -// file at the top-level directory of this distribution and at -// http://rust-lang.org/COPYRIGHT. -// -// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or -// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license -// <LICENSE-MIT or http://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::slice; -use core::iter::repeat; -use core::num::Wrapping as w; -use core::fmt; - -use {Rng, SeedableRng, Rand}; - -#[allow(bad_style)] -type w64 = w<u64>; - -const RAND_SIZE_64_LEN: usize = 8; -const RAND_SIZE_64: usize = 1 << RAND_SIZE_64_LEN; - -/// A random number generator that uses ISAAC-64[1], the 64-bit -/// variant of the ISAAC algorithm. -/// -/// The ISAAC algorithm is generally accepted as suitable for -/// cryptographic purposes, but this implementation has not be -/// verified as such. Prefer a generator like `OsRng` that defers to -/// the operating system for cases that need high security. -/// -/// [1]: Bob Jenkins, [*ISAAC: A fast cryptographic random number -/// generator*](http://www.burtleburtle.net/bob/rand/isaacafa.html) -#[derive(Copy)] -pub struct Isaac64Rng { - cnt: usize, - rsl: [w64; RAND_SIZE_64], - mem: [w64; RAND_SIZE_64], - a: w64, - b: w64, - c: w64, -} - -static EMPTY_64: Isaac64Rng = Isaac64Rng { - cnt: 0, - rsl: [w(0); RAND_SIZE_64], - mem: [w(0); RAND_SIZE_64], - a: w(0), b: w(0), c: w(0), -}; - -impl Isaac64Rng { - /// Create a 64-bit ISAAC random number generator using the - /// default fixed seed. - pub fn new_unseeded() -> Isaac64Rng { - let mut rng = EMPTY_64; - rng.init(false); - rng - } - - /// Initialises `self`. If `use_rsl` is true, then use the current value - /// of `rsl` as a seed, otherwise construct one algorithmically (not - /// randomly). - fn init(&mut self, use_rsl: bool) { - macro_rules! init { - ($var:ident) => ( - let mut $var = w(0x9e3779b97f4a7c13); - ) - } - init!(a); init!(b); init!(c); init!(d); - init!(e); init!(f); init!(g); init!(h); - - macro_rules! mix { - () => {{ - a=a-e; f=f^(h>>9); h=h+a; - b=b-f; g=g^(a<<9); a=a+b; - c=c-g; h=h^(b>>23); b=b+c; - d=d-h; a=a^(c<<15); c=c+d; - e=e-a; b=b^(d>>14); d=d+e; - f=f-b; c=c^(e<<20); e=e+f; - g=g-c; d=d^(f>>17); f=f+g; - h=h-d; e=e^(g<<14); g=g+h; - }} - } - - for _ in 0..4 { - mix!(); - } - - if use_rsl { - macro_rules! memloop { - ($arr:expr) => {{ - for i in (0..RAND_SIZE_64 / 8).map(|i| i * 8) { - a=a+$arr[i ]; b=b+$arr[i+1]; - c=c+$arr[i+2]; d=d+$arr[i+3]; - e=e+$arr[i+4]; f=f+$arr[i+5]; - g=g+$arr[i+6]; h=h+$arr[i+7]; - mix!(); - self.mem[i ]=a; self.mem[i+1]=b; - self.mem[i+2]=c; self.mem[i+3]=d; - self.mem[i+4]=e; self.mem[i+5]=f; - self.mem[i+6]=g; self.mem[i+7]=h; - } - }} - } - - memloop!(self.rsl); - memloop!(self.mem); - } else { - for i in (0..RAND_SIZE_64 / 8).map(|i| i * 8) { - mix!(); - self.mem[i ]=a; self.mem[i+1]=b; - self.mem[i+2]=c; self.mem[i+3]=d; - self.mem[i+4]=e; self.mem[i+5]=f; - self.mem[i+6]=g; self.mem[i+7]=h; - } - } - - self.isaac64(); - } - - /// Refills the output buffer (`self.rsl`) - fn isaac64(&mut self) { - self.c = self.c + w(1); - // abbreviations - let mut a = self.a; - let mut b = self.b + self.c; - const MIDPOINT: usize = RAND_SIZE_64 / 2; - const MP_VEC: [(usize, usize); 2] = [(0,MIDPOINT), (MIDPOINT, 0)]; - macro_rules! ind { - ($x:expr) => { - *self.mem.get_unchecked((($x >> 3usize).0 as usize) & (RAND_SIZE_64 - 1)) - } - } - - for &(mr_offset, m2_offset) in MP_VEC.iter() { - for base in (0..MIDPOINT / 4).map(|i| i * 4) { - - macro_rules! rngstepp { - ($j:expr, $shift:expr) => {{ - let base = base + $j; - let mix = a ^ (a << $shift); - let mix = if $j == 0 {!mix} else {mix}; - - unsafe { - let x = *self.mem.get_unchecked(base + mr_offset); - a = mix + *self.mem.get_unchecked(base + m2_offset); - let y = ind!(x) + a + b; - *self.mem.get_unchecked_mut(base + mr_offset) = y; - - b = ind!(y >> RAND_SIZE_64_LEN) + x; - *self.rsl.get_unchecked_mut(base + mr_offset) = b; - } - }} - } - - macro_rules! rngstepn { - ($j:expr, $shift:expr) => {{ - let base = base + $j; - let mix = a ^ (a >> $shift); - let mix = if $j == 0 {!mix} else {mix}; - - unsafe { - let x = *self.mem.get_unchecked(base + mr_offset); - a = mix + *self.mem.get_unchecked(base + m2_offset); - let y = ind!(x) + a + b; - *self.mem.get_unchecked_mut(base + mr_offset) = y; - - b = ind!(y >> RAND_SIZE_64_LEN) + x; - *self.rsl.get_unchecked_mut(base + mr_offset) = b; - } - }} - } - - rngstepp!(0, 21); - rngstepn!(1, 5); - rngstepp!(2, 12); - rngstepn!(3, 33); - } - } - - self.a = a; - self.b = b; - self.cnt = RAND_SIZE_64; - } -} - -// Cannot be derived because [u32; 256] does not implement Clone -impl Clone for Isaac64Rng { - fn clone(&self) -> Isaac64Rng { - *self - } -} - -impl Rng for Isaac64Rng { - #[inline] - fn next_u32(&mut self) -> u32 { - self.next_u64() as u32 - } - - #[inline] - fn next_u64(&mut self) -> u64 { - if self.cnt == 0 { - // make some more numbers - self.isaac64(); - } - self.cnt -= 1; - - // See corresponding location in IsaacRng.next_u32 for - // explanation. - debug_assert!(self.cnt < RAND_SIZE_64); - self.rsl[(self.cnt % RAND_SIZE_64) as usize].0 - } -} - -impl<'a> SeedableRng<&'a [u64]> for Isaac64Rng { - fn reseed(&mut self, seed: &'a [u64]) { - // make the seed into [seed[0], seed[1], ..., seed[seed.len() - // - 1], 0, 0, ...], to fill rng.rsl. - let seed_iter = seed.iter().map(|&x| x).chain(repeat(0u64)); - - for (rsl_elem, seed_elem) in self.rsl.iter_mut().zip(seed_iter) { - *rsl_elem = w(seed_elem); - } - self.cnt = 0; - self.a = w(0); - self.b = w(0); - self.c = w(0); - - self.init(true); - } - - /// Create an ISAAC random number generator with a seed. This can - /// be any length, although the maximum number of elements used is - /// 256 and any more will be silently ignored. A generator - /// constructed with a given seed will generate the same sequence - /// of values as all other generators constructed with that seed. - fn from_seed(seed: &'a [u64]) -> Isaac64Rng { - let mut rng = EMPTY_64; - rng.reseed(seed); - rng - } -} - -impl Rand for Isaac64Rng { - fn rand<R: Rng>(other: &mut R) -> Isaac64Rng { - let mut ret = EMPTY_64; - unsafe { - let ptr = ret.rsl.as_mut_ptr() as *mut u8; - - let slice = slice::from_raw_parts_mut(ptr, RAND_SIZE_64 * 8); - other.fill_bytes(slice); - } - ret.cnt = 0; - ret.a = w(0); - ret.b = w(0); - ret.c = w(0); - - ret.init(true); - return ret; - } -} - -impl fmt::Debug for Isaac64Rng { - fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { - write!(f, "Isaac64Rng {{}}") - } -} - -#[cfg(test)] -mod test { - use {Rng, SeedableRng}; - use super::Isaac64Rng; - - #[test] - fn test_rng_64_rand_seeded() { - let s = ::test::rng().gen_iter::<u64>().take(256).collect::<Vec<u64>>(); - let mut ra: Isaac64Rng = SeedableRng::from_seed(&s[..]); - let mut rb: Isaac64Rng = SeedableRng::from_seed(&s[..]); - assert!(::test::iter_eq(ra.gen_ascii_chars().take(100), - rb.gen_ascii_chars().take(100))); - } - - #[test] - fn test_rng_64_seeded() { - let seed: &[_] = &[1, 23, 456, 7890, 12345]; - let mut ra: Isaac64Rng = SeedableRng::from_seed(seed); - let mut rb: Isaac64Rng = SeedableRng::from_seed(seed); - assert!(::test::iter_eq(ra.gen_ascii_chars().take(100), - rb.gen_ascii_chars().take(100))); - } - - #[test] - fn test_rng_64_reseed() { - let s = ::test::rng().gen_iter::<u64>().take(256).collect::<Vec<u64>>(); - let mut r: Isaac64Rng = SeedableRng::from_seed(&s[..]); - let string1: String = r.gen_ascii_chars().take(100).collect(); - - r.reseed(&s[..]); - - let string2: String = r.gen_ascii_chars().take(100).collect(); - assert_eq!(string1, string2); - } - - #[test] - fn test_rng_64_true_values() { - let seed: &[_] = &[1, 23, 456, 7890, 12345]; - let mut ra: Isaac64Rng = SeedableRng::from_seed(seed); - // Regression test that isaac is actually using the above vector - let v = (0..10).map(|_| ra.next_u64()).collect::<Vec<_>>(); - assert_eq!(v, - vec!(547121783600835980, 14377643087320773276, 17351601304698403469, - 1238879483818134882, 11952566807690396487, 13970131091560099343, - 4469761996653280935, 15552757044682284409, 6860251611068737823, - 13722198873481261842)); - - let seed: &[_] = &[12345, 67890, 54321, 9876]; - let mut rb: Isaac64Rng = SeedableRng::from_seed(seed); - // skip forward to the 10000th number - for _ in 0..10000 { rb.next_u64(); } - - let v = (0..10).map(|_| rb.next_u64()).collect::<Vec<_>>(); - assert_eq!(v, - vec!(18143823860592706164, 8491801882678285927, 2699425367717515619, - 17196852593171130876, 2606123525235546165, 15790932315217671084, - 596345674630742204, 9947027391921273664, 11788097613744130851, - 10391409374914919106)); - } - - #[test] - fn test_rng_clone() { - let seed: &[_] = &[1, 23, 456, 7890, 12345]; - let mut rng: Isaac64Rng = SeedableRng::from_seed(seed); - let mut clone = rng.clone(); - for _ in 0..16 { - assert_eq!(rng.next_u64(), clone.next_u64()); - } - } -} diff --git a/rand/src/prng/mod.rs b/rand/src/prng/mod.rs index ed3e018..3c0d27b 100644 --- a/rand/src/prng/mod.rs +++ b/rand/src/prng/mod.rs @@ -1,51 +1,37 @@ -// Copyright 2017 The Rust Project Developers. See the COPYRIGHT -// file at the top-level directory of this distribution and at -// http://rust-lang.org/COPYRIGHT. +// Copyright 2018 Developers of the Rand project. // // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or -// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license -// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your +// 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. -//! Pseudo random number generators are algorithms to produce *apparently -//! random* numbers deterministically, and usually fairly quickly. +//! Pseudo-random number generators. +//! +//! This module is deprecated: //! -//! So long as the algorithm is computationally secure, is initialised with -//! sufficient entropy (i.e. unknown by an attacker), and its internal state is -//! also protected (unknown to an attacker), the output will also be -//! *computationally secure*. Computationally Secure Pseudo Random Number -//! Generators (CSPRNGs) are thus suitable sources of random numbers for -//! cryptography. There are a couple of gotchas here, however. First, the seed -//! used for initialisation must be unknown. Usually this should be provided by -//! the operating system and should usually be secure, however this may not -//! always be the case (especially soon after startup). Second, user-space -//! memory may be vulnerable, for example when written to swap space, and after -//! forking a child process should reinitialise any user-space PRNGs. For this -//! reason it may be preferable to source random numbers directly from the OS -//! for cryptographic applications. -//! -//! PRNGs are also widely used for non-cryptographic uses: randomised -//! algorithms, simulations, games. In these applications it is usually not -//! important for numbers to be cryptographically *unguessable*, but even -//! distribution and independence from other samples (from the point of view -//! of someone unaware of the algorithm used, at least) may still be important. -//! Good PRNGs should satisfy these properties, but do not take them for -//! granted; Wikipedia's article on -//! [Pseudorandom number generators](https://en.wikipedia.org/wiki/Pseudorandom_number_generator) -//! provides some background on this topic. -//! -//! Care should be taken when seeding (initialising) PRNGs. Some PRNGs have -//! short periods for some seeds. If one PRNG is seeded from another using the -//! same algorithm, it is possible that both will yield the same sequence of -//! values (with some lag). - -mod chacha; -mod isaac; -mod isaac64; -mod xorshift; +//! - documentation has moved to +//! [The Book](https://rust-random.github.io/book/guide-rngs.html), +//! - PRNGs have moved to other `rand_*` crates. -pub use self::chacha::ChaChaRng; -pub use self::isaac::IsaacRng; -pub use self::isaac64::Isaac64Rng; -pub use self::xorshift::XorShiftRng; +// Deprecations (to be removed in 0.7) +#[doc(hidden)] #[allow(deprecated)] +pub use deprecated::XorShiftRng; +#[doc(hidden)] pub mod isaac { + // Note: we miss `IsaacCore` here but probably unimportant. + #[allow(deprecated)] pub use deprecated::IsaacRng; +} +#[doc(hidden)] pub mod isaac64 { + #[allow(deprecated)] pub use deprecated::Isaac64Rng; +} +#[doc(hidden)] #[allow(deprecated)] pub use deprecated::{IsaacRng, Isaac64Rng}; +#[doc(hidden)] pub mod chacha { + // Note: we miss `ChaChaCore` here but probably unimportant. + #[allow(deprecated)] pub use deprecated::ChaChaRng; +} +#[doc(hidden)] #[allow(deprecated)] pub use deprecated::ChaChaRng; +#[doc(hidden)] pub mod hc128 { + // Note: we miss `Hc128Core` here but probably unimportant. + #[allow(deprecated)] pub use deprecated::Hc128Rng; +} +#[doc(hidden)] #[allow(deprecated)] pub use deprecated::Hc128Rng; diff --git a/rand/src/prng/xorshift.rs b/rand/src/prng/xorshift.rs deleted file mode 100644 index dd367e9..0000000 --- a/rand/src/prng/xorshift.rs +++ /dev/null @@ -1,101 +0,0 @@ -// Copyright 2017 The Rust Project Developers. See the COPYRIGHT -// file at the top-level directory of this distribution and at -// http://rust-lang.org/COPYRIGHT. -// -// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or -// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license -// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your -// option. This file may not be copied, modified, or distributed -// except according to those terms. - -//! Xorshift generators - -use core::num::Wrapping as w; -use {Rng, SeedableRng, Rand}; - -/// An Xorshift[1] random number -/// generator. -/// -/// The Xorshift algorithm is not suitable for cryptographic purposes -/// but is very fast. If you do not know for sure that it fits your -/// requirements, use a more secure one such as `IsaacRng` or `OsRng`. -/// -/// [1]: Marsaglia, George (July 2003). ["Xorshift -/// RNGs"](http://www.jstatsoft.org/v08/i14/paper). *Journal of -/// Statistical Software*. Vol. 8 (Issue 14). -#[allow(missing_copy_implementations)] -#[derive(Clone, Debug)] -pub struct XorShiftRng { - x: w<u32>, - y: w<u32>, - z: w<u32>, - w: w<u32>, -} - -impl XorShiftRng { - /// Creates a new XorShiftRng instance which is not seeded. - /// - /// The initial values of this RNG are constants, so all generators created - /// by this function will yield the same stream of random numbers. It is - /// highly recommended that this is created through `SeedableRng` instead of - /// this function - pub fn new_unseeded() -> XorShiftRng { - XorShiftRng { - x: w(0x193a6754), - y: w(0xa8a7d469), - z: w(0x97830e05), - w: w(0x113ba7bb), - } - } -} - -impl Rng for XorShiftRng { - #[inline] - fn next_u32(&mut self) -> u32 { - let x = self.x; - let t = x ^ (x << 11); - self.x = self.y; - self.y = self.z; - self.z = self.w; - let w_ = self.w; - self.w = w_ ^ (w_ >> 19) ^ (t ^ (t >> 8)); - self.w.0 - } -} - -impl SeedableRng<[u32; 4]> for XorShiftRng { - /// Reseed an XorShiftRng. This will panic if `seed` is entirely 0. - fn reseed(&mut self, seed: [u32; 4]) { - assert!(!seed.iter().all(|&x| x == 0), - "XorShiftRng.reseed called with an all zero seed."); - - self.x = w(seed[0]); - self.y = w(seed[1]); - self.z = w(seed[2]); - self.w = w(seed[3]); - } - - /// Create a new XorShiftRng. This will panic if `seed` is entirely 0. - fn from_seed(seed: [u32; 4]) -> XorShiftRng { - assert!(!seed.iter().all(|&x| x == 0), - "XorShiftRng::from_seed called with an all zero seed."); - - XorShiftRng { - x: w(seed[0]), - y: w(seed[1]), - z: w(seed[2]), - w: w(seed[3]), - } - } -} - -impl Rand for XorShiftRng { - fn rand<R: Rng>(rng: &mut R) -> XorShiftRng { - let mut tuple: (u32, u32, u32, u32) = rng.gen(); - while tuple == (0, 0, 0, 0) { - tuple = rng.gen(); - } - let (x, y, z, w_) = tuple; - XorShiftRng { x: w(x), y: w(y), z: w(z), w: w(w_) } - } -} |