From 986ad2f782cf944990e4eda8bf88ea1821233302 Mon Sep 17 00:00:00 2001 From: Robin Krahl Date: Tue, 11 Dec 2018 23:50:45 +0100 Subject: Add nitrokey as a dependency to nitrocli The nitrokey crate provides a simple interface to the Nitrokey Storage and the Nitrokey Pro based on the libnitrokey library developed by Nitrokey UG. The low-level bindings to this library are available in the nitrokey-sys crate. This patch adds version v0.2.1 of the nitrokey crate as a dependency for nitrocli. It includes the indirect dependencies nitrokey-sys (version 3.4.1) and rand (version 0.4.3). Import subrepo nitrokey/:nitrokey at 2eccc96ceec2282b868891befe9cda7f941fbe7b Import subrepo nitrokey-sys/:nitrokey-sys at f1a11ebf72610fb9cf80ac7f9f147b4ba1a5336f Import subrepo rand/:rand at d7d5da49daf7ceb3e5940072940d495cced3a1b3 --- rand/src/prng/chacha.rs | 321 +++++++++++++++++++++++++++++++++++++++++++ rand/src/prng/isaac.rs | 328 ++++++++++++++++++++++++++++++++++++++++++++ rand/src/prng/isaac64.rs | 340 ++++++++++++++++++++++++++++++++++++++++++++++ rand/src/prng/mod.rs | 51 +++++++ rand/src/prng/xorshift.rs | 101 ++++++++++++++ 5 files changed, 1141 insertions(+) create mode 100644 rand/src/prng/chacha.rs create mode 100644 rand/src/prng/isaac.rs create mode 100644 rand/src/prng/isaac64.rs create mode 100644 rand/src/prng/mod.rs create mode 100644 rand/src/prng/xorshift.rs (limited to 'rand/src/prng') diff --git a/rand/src/prng/chacha.rs b/rand/src/prng/chacha.rs new file mode 100644 index 0000000..a73e8e7 --- /dev/null +++ b/rand/src/prng/chacha.rs @@ -0,0 +1,321 @@ +// 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 or the MIT license +// , 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; + +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(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::().take(8).collect::>(); + 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::().take(8).collect::>(); + 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::>(); + 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::>(); + 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 = 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 new file mode 100644 index 0000000..cf5eb67 --- /dev/null +++ b/rand/src/prng/isaac.rs @@ -0,0 +1,328 @@ +// 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 or the MIT license +// , 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; + +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(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::().take(256).collect::>(); + 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::().take(256).collect::>(); + 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::>(); + 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::>(); + 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 new file mode 100644 index 0000000..b98e3fe --- /dev/null +++ b/rand/src/prng/isaac64.rs @@ -0,0 +1,340 @@ +// 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 or the MIT license +// , 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; + +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(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::().take(256).collect::>(); + 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::().take(256).collect::>(); + 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::>(); + 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::>(); + 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 new file mode 100644 index 0000000..ed3e018 --- /dev/null +++ b/rand/src/prng/mod.rs @@ -0,0 +1,51 @@ +// 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 or the MIT license +// , 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. +//! +//! 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; + +pub use self::chacha::ChaChaRng; +pub use self::isaac::IsaacRng; +pub use self::isaac64::Isaac64Rng; +pub use self::xorshift::XorShiftRng; diff --git a/rand/src/prng/xorshift.rs b/rand/src/prng/xorshift.rs new file mode 100644 index 0000000..dd367e9 --- /dev/null +++ b/rand/src/prng/xorshift.rs @@ -0,0 +1,101 @@ +// 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 or the MIT license +// , 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, + y: w, + z: w, + w: w, +} + +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(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_) } + } +} -- cgit v1.2.1