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-rw-r--r--rand/rand_chacha/src/chacha.rs452
-rw-r--r--rand/rand_chacha/src/lib.rs30
2 files changed, 0 insertions, 482 deletions
diff --git a/rand/rand_chacha/src/chacha.rs b/rand/rand_chacha/src/chacha.rs
deleted file mode 100644
index b1b89e0..0000000
--- a/rand/rand_chacha/src/chacha.rs
+++ /dev/null
@@ -1,452 +0,0 @@
-// 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 ChaCha random number generator.
-
-#[cfg(feature = "std")]
-use std as core;
-#[cfg(not(feature = "std"))]
-use core;
-
-use c2_chacha::guts::ChaCha;
-use self::core::fmt;
-use rand_core::block::{BlockRng, BlockRngCore};
-use rand_core::{CryptoRng, Error, RngCore, SeedableRng};
-
-const STREAM_PARAM_NONCE: u32 = 1;
-const STREAM_PARAM_BLOCK: u32 = 0;
-
-pub struct Array64<T>([T; 64]);
-impl<T> Default for Array64<T> where T: Default {
- fn default() -> Self {
- Self([T::default(), T::default(), T::default(), T::default(), T::default(), T::default(), T::default(), T::default(),
- T::default(), T::default(), T::default(), T::default(), T::default(), T::default(), T::default(), T::default(),
- T::default(), T::default(), T::default(), T::default(), T::default(), T::default(), T::default(), T::default(),
- T::default(), T::default(), T::default(), T::default(), T::default(), T::default(), T::default(), T::default(),
- T::default(), T::default(), T::default(), T::default(), T::default(), T::default(), T::default(), T::default(),
- T::default(), T::default(), T::default(), T::default(), T::default(), T::default(), T::default(), T::default(),
- T::default(), T::default(), T::default(), T::default(), T::default(), T::default(), T::default(), T::default(),
- T::default(), T::default(), T::default(), T::default(), T::default(), T::default(), T::default(), T::default()])
- }
-}
-impl<T> AsRef<[T]> for Array64<T> {
- fn as_ref(&self) -> &[T] {
- &self.0
- }
-}
-impl<T> AsMut<[T]> for Array64<T> {
- fn as_mut(&mut self) -> &mut [T] {
- &mut self.0
- }
-}
-impl<T> Clone for Array64<T> where T: Copy + Default {
- fn clone(&self) -> Self {
- let mut new = Self::default();
- new.0.copy_from_slice(&self.0);
- new
- }
-}
-impl<T> fmt::Debug for Array64<T> {
- fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
- write!(f, "Array64 {{}}")
- }
-}
-
-macro_rules! chacha_impl {
- ($ChaChaXCore:ident, $ChaChaXRng:ident, $rounds:expr, $doc:expr) => {
- #[doc=$doc]
- #[derive(Clone)]
- pub struct $ChaChaXCore {
- state: ChaCha,
- }
-
- // Custom Debug implementation that does not expose the internal state
- impl fmt::Debug for $ChaChaXCore {
- fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
- write!(f, "ChaChaXCore {{}}")
- }
- }
-
- impl BlockRngCore for $ChaChaXCore {
- type Item = u32;
- type Results = Array64<u32>;
- #[inline]
- fn generate(&mut self, r: &mut Self::Results) {
- // Fill slice of words by writing to equivalent slice of bytes, then fixing endianness.
- self.state.refill4($rounds, unsafe {
- &mut *(&mut *r as *mut Array64<u32> as *mut [u8; 256])
- });
- for x in r.as_mut() {
- *x = x.to_le();
- }
- }
- }
-
- impl SeedableRng for $ChaChaXCore {
- type Seed = [u8; 32];
- #[inline]
- fn from_seed(seed: Self::Seed) -> Self {
- $ChaChaXCore { state: ChaCha::new(&seed, &[0u8; 8]) }
- }
- }
-
- /// A cryptographically secure random number generator that uses the ChaCha algorithm.
- ///
- /// ChaCha is a stream cipher designed by Daniel J. Bernstein[^1], that we use as an RNG. It is
- /// an improved variant of the Salsa20 cipher family, which was selected as one of the "stream
- /// ciphers suitable for widespread adoption" by eSTREAM[^2].
- ///
- /// ChaCha uses add-rotate-xor (ARX) operations as its basis. These are safe against timing
- /// attacks, although that is mostly a concern for ciphers and not for RNGs. We provide a SIMD
- /// implementation to support high throughput on a variety of common hardware platforms.
- ///
- /// With the ChaCha algorithm it is possible to choose the number of rounds the core algorithm
- /// should run. The number of rounds is a tradeoff between performance and security, where 8
- /// rounds is the minimum potentially secure configuration, and 20 rounds is widely used as a
- /// conservative choice.
- ///
- /// We use a 64-bit counter and 64-bit stream identifier as in Bernstein's implementation[^1]
- /// except that we use a stream identifier in place of a nonce. A 64-bit counter over 64-byte
- /// (16 word) blocks allows 1 ZiB of output before cycling, and the stream identifier allows
- /// 2<sup>64</sup> unique streams of output per seed. Both counter and stream are initialized
- /// to zero but may be set via the `set_word_pos` and `set_stream` methods.
- ///
- /// The word layout is:
- ///
- /// ```text
- /// constant constant constant constant
- /// seed seed seed seed
- /// seed seed seed seed
- /// counter counter stream_id stream_id
- /// ```
- ///
- /// This implementation uses an output buffer of sixteen `u32` words, and uses
- /// [`BlockRng`] to implement the [`RngCore`] methods.
- ///
- /// [^1]: D. J. Bernstein, [*ChaCha, a variant of Salsa20*](
- /// https://cr.yp.to/chacha.html)
- ///
- /// [^2]: [eSTREAM: the ECRYPT Stream Cipher Project](
- /// http://www.ecrypt.eu.org/stream/)
- #[derive(Clone, Debug)]
- pub struct $ChaChaXRng {
- rng: BlockRng<$ChaChaXCore>,
- }
-
- impl SeedableRng for $ChaChaXRng {
- type Seed = [u8; 32];
- #[inline]
- fn from_seed(seed: Self::Seed) -> Self {
- let core = $ChaChaXCore::from_seed(seed);
- Self {
- rng: BlockRng::new(core),
- }
- }
- }
-
- impl RngCore for $ChaChaXRng {
- #[inline]
- fn next_u32(&mut self) -> u32 {
- self.rng.next_u32()
- }
- #[inline]
- fn next_u64(&mut self) -> u64 {
- self.rng.next_u64()
- }
- #[inline]
- fn fill_bytes(&mut self, bytes: &mut [u8]) {
- self.rng.fill_bytes(bytes)
- }
- #[inline]
- fn try_fill_bytes(&mut self, bytes: &mut [u8]) -> Result<(), Error> {
- self.rng.try_fill_bytes(bytes)
- }
- }
-
- impl $ChaChaXRng {
- // The buffer is a 4-block window, i.e. it is always at a block-aligned position in the
- // stream but if the stream has been seeked it may not be self-aligned.
-
- /// Get the offset from the start of the stream, in 32-bit words.
- ///
- /// Since the generated blocks are 16 words (2<sup>4</sup>) long and the
- /// counter is 64-bits, the offset is a 68-bit number. Sub-word offsets are
- /// not supported, hence the result can simply be multiplied by 4 to get a
- /// byte-offset.
- #[inline]
- pub fn get_word_pos(&self) -> u128 {
- let mut block = u128::from(self.rng.core.state.get_stream_param(STREAM_PARAM_BLOCK));
- // counter is incremented *after* filling buffer
- block -= 4;
- (block << 4) + self.rng.index() as u128
- }
-
- /// Set the offset from the start of the stream, in 32-bit words.
- ///
- /// As with `get_word_pos`, we use a 68-bit number. Since the generator
- /// simply cycles at the end of its period (1 ZiB), we ignore the upper
- /// 60 bits.
- #[inline]
- pub fn set_word_pos(&mut self, word_offset: u128) {
- let block = (word_offset >> 4) as u64;
- self.rng
- .core
- .state
- .set_stream_param(STREAM_PARAM_BLOCK, block);
- self.rng.generate_and_set((word_offset & 15) as usize);
- }
-
- /// Set the stream number.
- ///
- /// This is initialized to zero; 2<sup>64</sup> unique streams of output
- /// are available per seed/key.
- ///
- /// Note that in order to reproduce ChaCha output with a specific 64-bit
- /// nonce, one can convert that nonce to a `u64` in little-endian fashion
- /// and pass to this function. In theory a 96-bit nonce can be used by
- /// passing the last 64-bits to this function and using the first 32-bits as
- /// the most significant half of the 64-bit counter (which may be set
- /// indirectly via `set_word_pos`), but this is not directly supported.
- #[inline]
- pub fn set_stream(&mut self, stream: u64) {
- self.rng
- .core
- .state
- .set_stream_param(STREAM_PARAM_NONCE, stream);
- if self.rng.index() != 64 {
- let wp = self.get_word_pos();
- self.set_word_pos(wp);
- }
- }
- }
-
- impl CryptoRng for $ChaChaXRng {}
-
- impl From<$ChaChaXCore> for $ChaChaXRng {
- fn from(core: $ChaChaXCore) -> Self {
- $ChaChaXRng {
- rng: BlockRng::new(core),
- }
- }
- }
- }
-}
-
-chacha_impl!(ChaCha20Core, ChaCha20Rng, 10, "ChaCha with 20 rounds");
-chacha_impl!(ChaCha12Core, ChaCha12Rng, 6, "ChaCha with 12 rounds");
-chacha_impl!(ChaCha8Core, ChaCha8Rng, 4, "ChaCha with 8 rounds");
-
-#[cfg(test)]
-mod test {
- use rand_core::{RngCore, SeedableRng};
-
- type ChaChaRng = super::ChaCha20Rng;
-
- #[test]
- fn test_chacha_construction() {
- let seed = [
- 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, 3, 0, 0, 0, 0,
- 0, 0, 0,
- ];
- let mut rng1 = ChaChaRng::from_seed(seed);
- assert_eq!(rng1.next_u32(), 137206642);
-
- let mut rng2 = ChaChaRng::from_rng(rng1).unwrap();
- assert_eq!(rng2.next_u32(), 1325750369);
- }
-
- #[test]
- fn test_chacha_true_values_a() {
- // Test vectors 1 and 2 from
- // https://tools.ietf.org/html/draft-nir-cfrg-chacha20-poly1305-04
- let seed = [0u8; 32];
- let mut rng = ChaChaRng::from_seed(seed);
-
- let mut results = [0u32; 16];
- for i in results.iter_mut() {
- *i = rng.next_u32();
- }
- let expected = [
- 0xade0b876, 0x903df1a0, 0xe56a5d40, 0x28bd8653, 0xb819d2bd, 0x1aed8da0, 0xccef36a8,
- 0xc70d778b, 0x7c5941da, 0x8d485751, 0x3fe02477, 0x374ad8b8, 0xf4b8436a, 0x1ca11815,
- 0x69b687c3, 0x8665eeb2,
- ];
- assert_eq!(results, expected);
-
- for i in results.iter_mut() {
- *i = rng.next_u32();
- }
- let expected = [
- 0xbee7079f, 0x7a385155, 0x7c97ba98, 0x0d082d73, 0xa0290fcb, 0x6965e348, 0x3e53c612,
- 0xed7aee32, 0x7621b729, 0x434ee69c, 0xb03371d5, 0xd539d874, 0x281fed31, 0x45fb0a51,
- 0x1f0ae1ac, 0x6f4d794b,
- ];
- assert_eq!(results, expected);
- }
-
- #[test]
- fn test_chacha_true_values_b() {
- // Test vector 3 from
- // https://tools.ietf.org/html/draft-nir-cfrg-chacha20-poly1305-04
- let seed = [
- 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
- 0, 0, 1,
- ];
- let mut rng = ChaChaRng::from_seed(seed);
-
- // Skip block 0
- for _ in 0..16 {
- rng.next_u32();
- }
-
- let mut results = [0u32; 16];
- for i in results.iter_mut() {
- *i = rng.next_u32();
- }
- let expected = [
- 0x2452eb3a, 0x9249f8ec, 0x8d829d9b, 0xddd4ceb1, 0xe8252083, 0x60818b01, 0xf38422b8,
- 0x5aaa49c9, 0xbb00ca8e, 0xda3ba7b4, 0xc4b592d1, 0xfdf2732f, 0x4436274e, 0x2561b3c8,
- 0xebdd4aa6, 0xa0136c00,
- ];
- assert_eq!(results, expected);
- }
-
- #[test]
- fn test_chacha_true_values_c() {
- // Test vector 4 from
- // https://tools.ietf.org/html/draft-nir-cfrg-chacha20-poly1305-04
- let seed = [
- 0, 0xff, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
- 0, 0, 0, 0,
- ];
- let expected = [
- 0xfb4dd572, 0x4bc42ef1, 0xdf922636, 0x327f1394, 0xa78dea8f, 0x5e269039, 0xa1bebbc1,
- 0xcaf09aae, 0xa25ab213, 0x48a6b46c, 0x1b9d9bcb, 0x092c5be6, 0x546ca624, 0x1bec45d5,
- 0x87f47473, 0x96f0992e,
- ];
- let expected_end = 3 * 16;
- let mut results = [0u32; 16];
-
- // Test block 2 by skipping block 0 and 1
- let mut rng1 = ChaChaRng::from_seed(seed);
- for _ in 0..32 {
- rng1.next_u32();
- }
- for i in results.iter_mut() {
- *i = rng1.next_u32();
- }
- assert_eq!(results, expected);
- assert_eq!(rng1.get_word_pos(), expected_end);
-
- // Test block 2 by using `set_word_pos`
- let mut rng2 = ChaChaRng::from_seed(seed);
- rng2.set_word_pos(2 * 16);
- for i in results.iter_mut() {
- *i = rng2.next_u32();
- }
- assert_eq!(results, expected);
- assert_eq!(rng2.get_word_pos(), expected_end);
-
- // Test skipping behaviour with other types
- let mut buf = [0u8; 32];
- rng2.fill_bytes(&mut buf[..]);
- assert_eq!(rng2.get_word_pos(), expected_end + 8);
- rng2.fill_bytes(&mut buf[0..25]);
- assert_eq!(rng2.get_word_pos(), expected_end + 15);
- rng2.next_u64();
- assert_eq!(rng2.get_word_pos(), expected_end + 17);
- rng2.next_u32();
- rng2.next_u64();
- assert_eq!(rng2.get_word_pos(), expected_end + 20);
- rng2.fill_bytes(&mut buf[0..1]);
- assert_eq!(rng2.get_word_pos(), expected_end + 21);
- }
-
- #[test]
- fn test_chacha_multiple_blocks() {
- let seed = [
- 0, 0, 0, 0, 1, 0, 0, 0, 2, 0, 0, 0, 3, 0, 0, 0, 4, 0, 0, 0, 5, 0, 0, 0, 6, 0, 0, 0, 7,
- 0, 0, 0,
- ];
- let mut rng = ChaChaRng::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 results = [0u32; 16];
- for i in results.iter_mut() {
- *i = rng.next_u32();
- for _ in 0..16 {
- rng.next_u32();
- }
- }
- let expected = [
- 0xf225c81a, 0x6ab1be57, 0x04d42951, 0x70858036, 0x49884684, 0x64efec72, 0x4be2d186,
- 0x3615b384, 0x11cfa18e, 0xd3c50049, 0x75c775f6, 0x434c6530, 0x2c5bad8f, 0x898881dc,
- 0x5f1c86d9, 0xc1f8e7f4,
- ];
- assert_eq!(results, expected);
- }
-
- #[test]
- fn test_chacha_true_bytes() {
- let seed = [0u8; 32];
- let mut rng = ChaChaRng::from_seed(seed);
- let mut results = [0u8; 32];
- rng.fill_bytes(&mut results);
- let expected = [
- 118, 184, 224, 173, 160, 241, 61, 144, 64, 93, 106, 229, 83, 134, 189, 40, 189, 210,
- 25, 184, 160, 141, 237, 26, 168, 54, 239, 204, 139, 119, 13, 199,
- ];
- assert_eq!(results, expected);
- }
-
- #[test]
- fn test_chacha_nonce() {
- // Test vector 5 from
- // https://tools.ietf.org/html/draft-nir-cfrg-chacha20-poly1305-04
- // Although we do not support setting a nonce, we try it here anyway so
- // we can use this test vector.
- let seed = [0u8; 32];
- let mut rng = ChaChaRng::from_seed(seed);
- // 96-bit nonce in LE order is: 0,0,0,0, 0,0,0,0, 0,0,0,2
- rng.set_stream(2u64 << (24 + 32));
-
- let mut results = [0u32; 16];
- for i in results.iter_mut() {
- *i = rng.next_u32();
- }
- let expected = [
- 0x374dc6c2, 0x3736d58c, 0xb904e24a, 0xcd3f93ef, 0x88228b1a, 0x96a4dfb3, 0x5b76ab72,
- 0xc727ee54, 0x0e0e978a, 0xf3145c95, 0x1b748ea8, 0xf786c297, 0x99c28f5f, 0x628314e8,
- 0x398a19fa, 0x6ded1b53,
- ];
- assert_eq!(results, expected);
- }
-
- #[test]
- fn test_chacha_clone_streams() {
- let seed = [
- 0, 0, 0, 0, 1, 0, 0, 0, 2, 0, 0, 0, 3, 0, 0, 0, 4, 0, 0, 0, 5, 0, 0, 0, 6, 0, 0, 0, 7,
- 0, 0, 0,
- ];
- let mut rng = ChaChaRng::from_seed(seed);
- let mut clone = rng.clone();
- for _ in 0..16 {
- assert_eq!(rng.next_u64(), clone.next_u64());
- }
-
- rng.set_stream(51);
- for _ in 0..7 {
- assert!(rng.next_u32() != clone.next_u32());
- }
- clone.set_stream(51); // switch part way through block
- for _ in 7..16 {
- assert_eq!(rng.next_u32(), clone.next_u32());
- }
- }
-}
diff --git a/rand/rand_chacha/src/lib.rs b/rand/rand_chacha/src/lib.rs
deleted file mode 100644
index e374bdd..0000000
--- a/rand/rand_chacha/src/lib.rs
+++ /dev/null
@@ -1,30 +0,0 @@
-// 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 ChaCha 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))))]
-
-#![cfg_attr(not(feature = "std"), no_std)]
-
-pub use rand_core;
-
-mod chacha;
-
-pub use crate::chacha::{ChaCha12Core, ChaCha12Rng, ChaCha20Core, ChaCha20Rng, ChaCha8Core, ChaCha8Rng};
-
-/// ChaCha with 20 rounds
-pub type ChaChaRng = ChaCha20Rng;
-/// ChaCha with 20 rounds, low-level interface
-pub type ChaChaCore = ChaCha20Core;