From aa6a1a8b863b7899145852b7c1e8f672adcee9ea Mon Sep 17 00:00:00 2001 From: Diggory Hardy Date: Wed, 10 Sep 2025 08:11:18 +0100 Subject: [PATCH 1/5] Move rand_chacha from rand repository --- Cargo.toml | 1 + rand_chacha/CHANGELOG.md | 46 +++ rand_chacha/COPYRIGHT | 12 + rand_chacha/Cargo.toml | 36 ++ rand_chacha/LICENSE-APACHE | 176 ++++++++++ rand_chacha/LICENSE-MIT | 26 ++ rand_chacha/README.md | 48 +++ rand_chacha/src/chacha.rs | 651 +++++++++++++++++++++++++++++++++++++ rand_chacha/src/guts.rs | 287 ++++++++++++++++ rand_chacha/src/lib.rs | 106 ++++++ 10 files changed, 1389 insertions(+) create mode 100644 rand_chacha/CHANGELOG.md create mode 100644 rand_chacha/COPYRIGHT create mode 100644 rand_chacha/Cargo.toml create mode 100644 rand_chacha/LICENSE-APACHE create mode 100644 rand_chacha/LICENSE-MIT create mode 100644 rand_chacha/README.md create mode 100644 rand_chacha/src/chacha.rs create mode 100644 rand_chacha/src/guts.rs create mode 100644 rand_chacha/src/lib.rs diff --git a/Cargo.toml b/Cargo.toml index f9cc4350..58645f77 100644 --- a/Cargo.toml +++ b/Cargo.toml @@ -1,5 +1,6 @@ [workspace] members = [ + "rand_chacha", "rand_jitter", "rand_isaac", "rand_xorshift", diff --git a/rand_chacha/CHANGELOG.md b/rand_chacha/CHANGELOG.md new file mode 100644 index 00000000..7965cf76 --- /dev/null +++ b/rand_chacha/CHANGELOG.md @@ -0,0 +1,46 @@ +# Changelog +All notable changes to this project will be documented in this file. + +The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/) +and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html). + +## [0.9.0] - 2025-01-27 +### Dependencies and features +- Update to `rand_core` v0.9.0 (#1558) +- Feature `std` now implies feature `rand_core/std` (#1153) +- Rename feature `serde1` to `serde` (#1477) +- Rename feature `getrandom` to `os_rng` (#1537) + +### Other changes +- Remove usage of `unsafe` in `fn generate` (#1181) then optimise for AVX2 (~4-7%) (#1192) +- Revise crate docs (#1454) + +## [0.3.1] - 2021-06-09 +- add getters corresponding to existing setters: `get_seed`, `get_stream` (#1124) +- add serde support, gated by the `serde1` feature (#1124) +- ensure expected layout via `repr(transparent)` (#1120) + +## [0.3.0] - 2020-12-08 +- Bump `rand_core` version to 0.6.0 +- Bump MSRV to 1.36 (#1011) +- Remove usage of deprecated feature "simd" of `ppv-lite86` (#979), then revert + this change (#1023) since SIMD is only enabled by default from `ppv-lite86 v0.2.10` +- impl PartialEq+Eq for ChaChaXRng and ChaChaXCore (#979) +- Fix panic on block counter wrap that was occurring in debug builds (#980) + +## [0.2.2] - 2020-03-09 +- Integrate `c2-chacha`, reducing dependency count (#931) +- Add CryptoRng to ChaChaXCore (#944) + +## [0.2.1] - 2019-07-22 +- Force enable the `simd` feature of `c2-chacha` (#845) + +## [0.2.0] - 2019-06-06 +- Rewrite based on the much faster `c2-chacha` crate (#789) + +## [0.1.1] - 2019-01-04 +- Disable `i128` and `u128` if the `target_os` is `emscripten` (#671: work-around Emscripten limitation) +- Update readme and doc links + +## [0.1.0] - 2018-10-17 +- Pulled out of the Rand crate diff --git a/rand_chacha/COPYRIGHT b/rand_chacha/COPYRIGHT new file mode 100644 index 00000000..468d907c --- /dev/null +++ b/rand_chacha/COPYRIGHT @@ -0,0 +1,12 @@ +Copyrights in the Rand project are retained by their contributors. No +copyright assignment is required to contribute to the Rand project. + +For full authorship information, see the version control history. + +Except as otherwise noted (below and/or in individual files), Rand is +licensed under the Apache License, Version 2.0 or + or the MIT license + or , at your option. + +The Rand project includes code from the Rust project +published under these same licenses. diff --git a/rand_chacha/Cargo.toml b/rand_chacha/Cargo.toml new file mode 100644 index 00000000..5f3a8676 --- /dev/null +++ b/rand_chacha/Cargo.toml @@ -0,0 +1,36 @@ +[package] +name = "rand_chacha" +version = "0.9.0" +authors = ["The Rand Project Developers", "The Rust Project Developers", "The CryptoCorrosion Contributors"] +license = "MIT OR Apache-2.0" +readme = "README.md" +repository = "https://github.com/rust-random/rand" +documentation = "https://docs.rs/rand_chacha" +homepage = "https://rust-random.github.io/book" +description = """ +ChaCha random number generator +""" +keywords = ["random", "rng", "chacha"] +categories = ["algorithms", "no-std"] +edition = "2021" +rust-version = "1.63" + +[package.metadata.docs.rs] +all-features = true +rustdoc-args = ["--generate-link-to-definition"] + +[dependencies] +rand_core = "0.9.0" +ppv-lite86 = { version = "0.2.14", default-features = false, features = ["simd"] } +serde = { version = "1.0", features = ["derive"], optional = true } + +[dev-dependencies] +# Only to test serde +serde_json = "1.0.120" +rand_core = { version = "0.9.0", features = ["os_rng"] } + +[features] +default = ["std"] +os_rng = ["rand_core/os_rng"] +std = ["ppv-lite86/std", "rand_core/std"] +serde = ["dep:serde"] diff --git a/rand_chacha/LICENSE-APACHE b/rand_chacha/LICENSE-APACHE new file mode 100644 index 00000000..494ad3bf --- /dev/null +++ b/rand_chacha/LICENSE-APACHE @@ -0,0 +1,176 @@ + Apache License + Version 2.0, January 2004 + https://www.apache.org/licenses/ + +TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION + +1. 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IN NO EVENT +SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY +CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION +OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR +IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER +DEALINGS IN THE SOFTWARE. diff --git a/rand_chacha/README.md b/rand_chacha/README.md new file mode 100644 index 00000000..167417f8 --- /dev/null +++ b/rand_chacha/README.md @@ -0,0 +1,48 @@ +# rand_chacha + +[![Test Status](https://github.com/rust-random/rand/actions/workflows/test.yml/badge.svg?event=push)](https://github.com/rust-random/rand/actions) +[![Latest version](https://img.shields.io/crates/v/rand_chacha.svg)](https://crates.io/crates/rand_chacha) +[![Book](https://img.shields.io/badge/book-master-yellow.svg)](https://rust-random.github.io/book/) +[![API](https://img.shields.io/badge/api-master-yellow.svg)](https://rust-random.github.io/rand/rand_chacha) +[![API](https://docs.rs/rand_chacha/badge.svg)](https://docs.rs/rand_chacha) + +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]. + +The RNGs provided by this crate are implemented via the fast stream ciphers of +the [`c2-chacha`](https://crates.io/crates/c2-chacha) crate. + +Links: + +- [API documentation (master)](https://rust-random.github.io/rand/rand_chacha) +- [API documentation (docs.rs)](https://docs.rs/rand_chacha) +- [Changelog](https://github.com/rust-random/rand/blob/master/rand_chacha/CHANGELOG.md) + +[rand]: https://crates.io/crates/rand +[^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/) + + +## Crate Features + +`rand_chacha` is `no_std` compatible when disabling default features; the `std` +feature can be explicitly required to re-enable `std` support. Using `std` +allows detection of CPU features and thus better optimisation. Using `std` +also enables `os_rng` functionality, such as `ChaCha20Rng::from_os_rng()`. + + +# License + +`rand_chacha` is distributed under the terms of both the MIT license and the +Apache License (Version 2.0). + +See [LICENSE-APACHE](LICENSE-APACHE) and [LICENSE-MIT](LICENSE-MIT), and +[COPYRIGHT](COPYRIGHT) for details. diff --git a/rand_chacha/src/chacha.rs b/rand_chacha/src/chacha.rs new file mode 100644 index 00000000..91d3cd62 --- /dev/null +++ b/rand_chacha/src/chacha.rs @@ -0,0 +1,651 @@ +// Copyright 2018 Developers of the Rand project. +// +// 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 crate::guts::ChaCha; +use core::fmt; +use rand_core::block::{BlockRng, BlockRngCore, CryptoBlockRng}; +use rand_core::{CryptoRng, RngCore, SeedableRng}; + +#[cfg(feature = "serde")] +use serde::{Deserialize, Deserializer, Serialize, Serializer}; + +// NB. this must remain consistent with some currently hard-coded numbers in this module +const BUF_BLOCKS: u8 = 4; +// number of 32-bit words per ChaCha block (fixed by algorithm definition) +const BLOCK_WORDS: u8 = 16; + +#[repr(transparent)] +pub struct Array64([T; 64]); +impl Default for Array64 +where + T: Default, +{ + #[rustfmt::skip] + 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 AsRef<[T]> for Array64 { + fn as_ref(&self) -> &[T] { + &self.0 + } +} +impl AsMut<[T]> for Array64 { + fn as_mut(&mut self) -> &mut [T] { + &mut self.0 + } +} +impl Clone for Array64 +where + T: Copy + Default, +{ + fn clone(&self) -> Self { + let mut new = Self::default(); + new.0.copy_from_slice(&self.0); + new + } +} +impl fmt::Debug for Array64 { + fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { + write!(f, "Array64 {{}}") + } +} + +macro_rules! chacha_impl { + ($ChaChaXCore:ident, $ChaChaXRng:ident, $rounds:expr, $doc:expr, $abst:ident,) => { + #[doc=$doc] + #[derive(Clone, PartialEq, Eq)] + 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 $ChaChaXCore { + type Item = u32; + type Results = Array64; + + #[inline] + fn generate(&mut self, r: &mut Self::Results) { + self.state.refill4($rounds, &mut r.0); + } + } + + impl SeedableRng for $ChaChaXCore { + type Seed = [u8; 32]; + + #[inline] + fn from_seed(seed: Self::Seed) -> Self { + $ChaChaXCore { + state: ChaCha::new(&seed, &[0u8; 8]), + } + } + } + + impl CryptoBlockRng for $ChaChaXCore {} + + /// 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 + /// 264 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) + } + } + + 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 sought 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 (24) 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 buf_start_block = { + let buf_end_block = self.rng.core.state.get_block_pos(); + u64::wrapping_sub(buf_end_block, BUF_BLOCKS.into()) + }; + let (buf_offset_blocks, block_offset_words) = { + let buf_offset_words = self.rng.index() as u64; + let blocks_part = buf_offset_words / u64::from(BLOCK_WORDS); + let words_part = buf_offset_words % u64::from(BLOCK_WORDS); + (blocks_part, words_part) + }; + let pos_block = u64::wrapping_add(buf_start_block, buf_offset_blocks); + let pos_block_words = u128::from(pos_block) * u128::from(BLOCK_WORDS); + pos_block_words + u128::from(block_offset_words) + } + + /// 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 / u128::from(BLOCK_WORDS)) as u64; + self.rng.core.state.set_block_pos(block); + self.rng + .generate_and_set((word_offset % u128::from(BLOCK_WORDS)) as usize); + } + + /// Set the stream number. + /// + /// This is initialized to zero; 264 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_nonce(stream); + if self.rng.index() != 64 { + let wp = self.get_word_pos(); + self.set_word_pos(wp); + } + } + + /// Get the stream number. + #[inline] + pub fn get_stream(&self) -> u64 { + self.rng.core.state.get_nonce() + } + + /// Get the seed. + #[inline] + pub fn get_seed(&self) -> [u8; 32] { + self.rng.core.state.get_seed() + } + } + + impl CryptoRng for $ChaChaXRng {} + + impl From<$ChaChaXCore> for $ChaChaXRng { + fn from(core: $ChaChaXCore) -> Self { + $ChaChaXRng { + rng: BlockRng::new(core), + } + } + } + + impl PartialEq<$ChaChaXRng> for $ChaChaXRng { + fn eq(&self, rhs: &$ChaChaXRng) -> bool { + let a: $abst::$ChaChaXRng = self.into(); + let b: $abst::$ChaChaXRng = rhs.into(); + a == b + } + } + impl Eq for $ChaChaXRng {} + + #[cfg(feature = "serde")] + impl Serialize for $ChaChaXRng { + fn serialize(&self, s: S) -> Result + where + S: Serializer, + { + $abst::$ChaChaXRng::from(self).serialize(s) + } + } + #[cfg(feature = "serde")] + impl<'de> Deserialize<'de> for $ChaChaXRng { + fn deserialize(d: D) -> Result + where + D: Deserializer<'de>, + { + $abst::$ChaChaXRng::deserialize(d).map(|x| Self::from(&x)) + } + } + + mod $abst { + #[cfg(feature = "serde")] + use serde::{Deserialize, Serialize}; + + // The abstract state of a ChaCha stream, independent of implementation choices. The + // comparison and serialization of this object is considered a semver-covered part of + // the API. + #[derive(Debug, PartialEq, Eq)] + #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))] + pub(crate) struct $ChaChaXRng { + seed: [u8; 32], + stream: u64, + word_pos: u128, + } + + impl From<&super::$ChaChaXRng> for $ChaChaXRng { + // Forget all information about the input except what is necessary to determine the + // outputs of any sequence of pub API calls. + fn from(r: &super::$ChaChaXRng) -> Self { + Self { + seed: r.get_seed(), + stream: r.get_stream(), + word_pos: r.get_word_pos(), + } + } + } + + impl From<&$ChaChaXRng> for super::$ChaChaXRng { + // Construct one of the possible concrete RNGs realizing an abstract state. + fn from(a: &$ChaChaXRng) -> Self { + use rand_core::SeedableRng; + let mut r = Self::from_seed(a.seed); + r.set_stream(a.stream); + r.set_word_pos(a.word_pos); + r + } + } + } + }; +} + +chacha_impl!( + ChaCha20Core, + ChaCha20Rng, + 10, + "ChaCha with 20 rounds", + abstract20, +); +chacha_impl!( + ChaCha12Core, + ChaCha12Rng, + 6, + "ChaCha with 12 rounds", + abstract12, +); +chacha_impl!( + ChaCha8Core, + ChaCha8Rng, + 4, + "ChaCha with 8 rounds", + abstract8, +); + +#[cfg(test)] +mod test { + use rand_core::{RngCore, SeedableRng}; + + #[cfg(feature = "serde")] + use super::{ChaCha12Rng, ChaCha20Rng, ChaCha8Rng}; + + type ChaChaRng = super::ChaCha20Rng; + + #[cfg(feature = "serde")] + #[test] + fn test_chacha_serde_roundtrip() { + let seed = [ + 1, 0, 52, 0, 0, 0, 0, 0, 1, 0, 10, 0, 22, 32, 0, 0, 2, 0, 55, 49, 0, 11, 0, 0, 3, 0, 0, + 0, 0, 0, 2, 92, + ]; + let mut rng1 = ChaCha20Rng::from_seed(seed); + let mut rng2 = ChaCha12Rng::from_seed(seed); + let mut rng3 = ChaCha8Rng::from_seed(seed); + + let encoded1 = serde_json::to_string(&rng1).unwrap(); + let encoded2 = serde_json::to_string(&rng2).unwrap(); + let encoded3 = serde_json::to_string(&rng3).unwrap(); + + let mut decoded1: ChaCha20Rng = serde_json::from_str(&encoded1).unwrap(); + let mut decoded2: ChaCha12Rng = serde_json::from_str(&encoded2).unwrap(); + let mut decoded3: ChaCha8Rng = serde_json::from_str(&encoded3).unwrap(); + + assert_eq!(rng1, decoded1); + assert_eq!(rng2, decoded2); + assert_eq!(rng3, decoded3); + + assert_eq!(rng1.next_u32(), decoded1.next_u32()); + assert_eq!(rng2.next_u32(), decoded2.next_u32()); + assert_eq!(rng3.next_u32(), decoded3.next_u32()); + } + + // This test validates that: + // 1. a hard-coded serialization demonstrating the format at time of initial release can still + // be deserialized to a ChaChaRng + // 2. re-serializing the resultant object produces exactly the original string + // + // Condition 2 is stronger than necessary: an equivalent serialization (e.g. with field order + // permuted, or whitespace differences) would also be admissible, but would fail this test. + // However testing for equivalence of serialized data is difficult, and there shouldn't be any + // reason we need to violate the stronger-than-needed condition, e.g. by changing the field + // definition order. + #[cfg(feature = "serde")] + #[test] + fn test_chacha_serde_format_stability() { + let j = r#"{"seed":[4,8,15,16,23,42,4,8,15,16,23,42,4,8,15,16,23,42,4,8,15,16,23,42,4,8,15,16,23,42,4,8],"stream":27182818284,"word_pos":314159265359}"#; + let r: ChaChaRng = serde_json::from_str(j).unwrap(); + let j1 = serde_json::to_string(&r).unwrap(); + assert_eq!(j, j1); + } + + #[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(&mut rng1); + 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()); + } + } + + #[test] + fn test_chacha_word_pos_wrap_exact() { + use super::{BLOCK_WORDS, BUF_BLOCKS}; + let mut rng = ChaChaRng::from_seed(Default::default()); + // refilling the buffer in set_word_pos will wrap the block counter to 0 + let last_block = (1 << 68) - u128::from(BUF_BLOCKS * BLOCK_WORDS); + rng.set_word_pos(last_block); + assert_eq!(rng.get_word_pos(), last_block); + } + + #[test] + fn test_chacha_word_pos_wrap_excess() { + use super::BLOCK_WORDS; + let mut rng = ChaChaRng::from_seed(Default::default()); + // refilling the buffer in set_word_pos will wrap the block counter past 0 + let last_block = (1 << 68) - u128::from(BLOCK_WORDS); + rng.set_word_pos(last_block); + assert_eq!(rng.get_word_pos(), last_block); + } + + #[test] + fn test_chacha_word_pos_zero() { + let mut rng = ChaChaRng::from_seed(Default::default()); + assert_eq!(rng.get_word_pos(), 0); + rng.set_word_pos(0); + assert_eq!(rng.get_word_pos(), 0); + } + + #[test] + fn test_trait_objects() { + use rand_core::CryptoRng; + + let mut rng1 = ChaChaRng::from_seed(Default::default()); + let rng2 = &mut rng1.clone() as &mut dyn CryptoRng; + for _ in 0..1000 { + assert_eq!(rng1.next_u64(), rng2.next_u64()); + } + } +} diff --git a/rand_chacha/src/guts.rs b/rand_chacha/src/guts.rs new file mode 100644 index 00000000..d077225c --- /dev/null +++ b/rand_chacha/src/guts.rs @@ -0,0 +1,287 @@ +// Copyright 2019 The CryptoCorrosion Contributors +// Copyright 2020 Developers of the Rand project. +// +// 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 ppv_lite86::{dispatch, dispatch_light128}; + +pub use ppv_lite86::Machine; +use ppv_lite86::{ + vec128_storage, ArithOps, BitOps32, LaneWords4, MultiLane, StoreBytes, Vec4, Vec4Ext, Vector, +}; + +pub(crate) const BLOCK: usize = 16; +pub(crate) const BLOCK64: u64 = BLOCK as u64; +const LOG2_BUFBLOCKS: u64 = 2; +const BUFBLOCKS: u64 = 1 << LOG2_BUFBLOCKS; +pub(crate) const BUFSZ64: u64 = BLOCK64 * BUFBLOCKS; +pub(crate) const BUFSZ: usize = BUFSZ64 as usize; + +const STREAM_PARAM_NONCE: u32 = 1; +const STREAM_PARAM_BLOCK: u32 = 0; + +#[derive(Clone, PartialEq, Eq)] +pub struct ChaCha { + pub(crate) b: vec128_storage, + pub(crate) c: vec128_storage, + pub(crate) d: vec128_storage, +} + +#[derive(Clone)] +pub struct State { + pub(crate) a: V, + pub(crate) b: V, + pub(crate) c: V, + pub(crate) d: V, +} + +#[inline(always)] +pub(crate) fn round(mut x: State) -> State { + x.a += x.b; + x.d = (x.d ^ x.a).rotate_each_word_right16(); + x.c += x.d; + x.b = (x.b ^ x.c).rotate_each_word_right20(); + x.a += x.b; + x.d = (x.d ^ x.a).rotate_each_word_right24(); + x.c += x.d; + x.b = (x.b ^ x.c).rotate_each_word_right25(); + x +} + +#[inline(always)] +pub(crate) fn diagonalize(mut x: State) -> State { + x.b = x.b.shuffle_lane_words3012(); + x.c = x.c.shuffle_lane_words2301(); + x.d = x.d.shuffle_lane_words1230(); + x +} +#[inline(always)] +pub(crate) fn undiagonalize(mut x: State) -> State { + x.b = x.b.shuffle_lane_words1230(); + x.c = x.c.shuffle_lane_words2301(); + x.d = x.d.shuffle_lane_words3012(); + x +} + +impl ChaCha { + #[inline(always)] + pub fn new(key: &[u8; 32], nonce: &[u8]) -> Self { + init_chacha(key, nonce) + } + + /// Produce 4 blocks of output, advancing the state + #[inline(always)] + pub fn refill4(&mut self, drounds: u32, out: &mut [u32; BUFSZ]) { + refill_wide(self, drounds, out) + } + + #[inline(always)] + pub fn set_block_pos(&mut self, value: u64) { + set_stream_param(self, STREAM_PARAM_BLOCK, value) + } + + #[inline(always)] + pub fn get_block_pos(&self) -> u64 { + get_stream_param(self, STREAM_PARAM_BLOCK) + } + + #[inline(always)] + pub fn set_nonce(&mut self, value: u64) { + set_stream_param(self, STREAM_PARAM_NONCE, value) + } + + #[inline(always)] + pub fn get_nonce(&self) -> u64 { + get_stream_param(self, STREAM_PARAM_NONCE) + } + + #[inline(always)] + pub fn get_seed(&self) -> [u8; 32] { + get_seed(self) + } +} + +// This implementation is platform-independent. +#[inline(always)] +#[cfg(target_endian = "big")] +fn add_pos(_m: Mach, d0: Mach::u32x4, i: u64) -> Mach::u32x4 { + let pos0 = ((d0.extract(1) as u64) << 32) | d0.extract(0) as u64; + let pos = pos0.wrapping_add(i); + d0.insert((pos >> 32) as u32, 1).insert(pos as u32, 0) +} +#[inline(always)] +#[cfg(target_endian = "big")] +fn d0123(m: Mach, d: vec128_storage) -> Mach::u32x4x4 { + let d0: Mach::u32x4 = m.unpack(d); + let mut pos = ((d0.extract(1) as u64) << 32) | d0.extract(0) as u64; + pos = pos.wrapping_add(1); + let d1 = d0.insert((pos >> 32) as u32, 1).insert(pos as u32, 0); + pos = pos.wrapping_add(1); + let d2 = d0.insert((pos >> 32) as u32, 1).insert(pos as u32, 0); + pos = pos.wrapping_add(1); + let d3 = d0.insert((pos >> 32) as u32, 1).insert(pos as u32, 0); + Mach::u32x4x4::from_lanes([d0, d1, d2, d3]) +} + +// Pos is packed into the state vectors as a little-endian u64, +// so on LE platforms we can use native vector ops to increment it. +#[inline(always)] +#[cfg(target_endian = "little")] +fn add_pos(m: Mach, d: Mach::u32x4, i: u64) -> Mach::u32x4 { + let d0: Mach::u64x2 = m.unpack(d.into()); + let incr = m.vec([i, 0]); + m.unpack((d0 + incr).into()) +} +#[inline(always)] +#[cfg(target_endian = "little")] +fn d0123(m: Mach, d: vec128_storage) -> Mach::u32x4x4 { + let d0: Mach::u64x2 = m.unpack(d); + let incr = + Mach::u64x2x4::from_lanes([m.vec([0, 0]), m.vec([1, 0]), m.vec([2, 0]), m.vec([3, 0])]); + m.unpack((Mach::u64x2x4::from_lanes([d0, d0, d0, d0]) + incr).into()) +} + +#[allow(clippy::many_single_char_names)] +#[inline(always)] +fn refill_wide_impl( + m: Mach, + state: &mut ChaCha, + drounds: u32, + out: &mut [u32; BUFSZ], +) { + let k = m.vec([0x6170_7865, 0x3320_646e, 0x7962_2d32, 0x6b20_6574]); + let b = m.unpack(state.b); + let c = m.unpack(state.c); + let mut x = State { + a: Mach::u32x4x4::from_lanes([k, k, k, k]), + b: Mach::u32x4x4::from_lanes([b, b, b, b]), + c: Mach::u32x4x4::from_lanes([c, c, c, c]), + d: d0123(m, state.d), + }; + for _ in 0..drounds { + x = round(x); + x = undiagonalize(round(diagonalize(x))); + } + let kk = Mach::u32x4x4::from_lanes([k, k, k, k]); + let sb = m.unpack(state.b); + let sb = Mach::u32x4x4::from_lanes([sb, sb, sb, sb]); + let sc = m.unpack(state.c); + let sc = Mach::u32x4x4::from_lanes([sc, sc, sc, sc]); + let sd = d0123(m, state.d); + let results = Mach::u32x4x4::transpose4(x.a + kk, x.b + sb, x.c + sc, x.d + sd); + out[0..16].copy_from_slice(&results.0.to_scalars()); + out[16..32].copy_from_slice(&results.1.to_scalars()); + out[32..48].copy_from_slice(&results.2.to_scalars()); + out[48..64].copy_from_slice(&results.3.to_scalars()); + state.d = add_pos(m, sd.to_lanes()[0], 4).into(); +} + +dispatch!(m, Mach, { + fn refill_wide(state: &mut ChaCha, drounds: u32, out: &mut [u32; BUFSZ]) { + refill_wide_impl(m, state, drounds, out); + } +}); + +// Single-block, rounds-only; shared by try_apply_keystream for tails shorter than BUFSZ +// and XChaCha's setup step. +dispatch!(m, Mach, { + fn refill_narrow_rounds(state: &mut ChaCha, drounds: u32) -> State { + let k: Mach::u32x4 = m.vec([0x6170_7865, 0x3320_646e, 0x7962_2d32, 0x6b20_6574]); + let mut x = State { + a: k, + b: m.unpack(state.b), + c: m.unpack(state.c), + d: m.unpack(state.d), + }; + for _ in 0..drounds { + x = round(x); + x = undiagonalize(round(diagonalize(x))); + } + State { + a: x.a.into(), + b: x.b.into(), + c: x.c.into(), + d: x.d.into(), + } + } +}); + +dispatch_light128!(m, Mach, { + fn set_stream_param(state: &mut ChaCha, param: u32, value: u64) { + let d: Mach::u32x4 = m.unpack(state.d); + state.d = d + .insert((value >> 32) as u32, (param << 1) | 1) + .insert(value as u32, param << 1) + .into(); + } +}); + +dispatch_light128!(m, Mach, { + fn get_stream_param(state: &ChaCha, param: u32) -> u64 { + let d: Mach::u32x4 = m.unpack(state.d); + ((d.extract((param << 1) | 1) as u64) << 32) | d.extract(param << 1) as u64 + } +}); + +dispatch_light128!(m, Mach, { + fn get_seed(state: &ChaCha) -> [u8; 32] { + let b: Mach::u32x4 = m.unpack(state.b); + let c: Mach::u32x4 = m.unpack(state.c); + let mut key = [0u8; 32]; + b.write_le(&mut key[..16]); + c.write_le(&mut key[16..]); + key + } +}); + +fn read_u32le(xs: &[u8]) -> u32 { + assert_eq!(xs.len(), 4); + u32::from(xs[0]) | (u32::from(xs[1]) << 8) | (u32::from(xs[2]) << 16) | (u32::from(xs[3]) << 24) +} + +dispatch_light128!(m, Mach, { + fn init_chacha(key: &[u8; 32], nonce: &[u8]) -> ChaCha { + let ctr_nonce = [ + 0, + if nonce.len() == 12 { + read_u32le(&nonce[0..4]) + } else { + 0 + }, + read_u32le(&nonce[nonce.len() - 8..nonce.len() - 4]), + read_u32le(&nonce[nonce.len() - 4..]), + ]; + let key0: Mach::u32x4 = m.read_le(&key[..16]); + let key1: Mach::u32x4 = m.read_le(&key[16..]); + ChaCha { + b: key0.into(), + c: key1.into(), + d: ctr_nonce.into(), + } + } +}); + +dispatch_light128!(m, Mach, { + fn init_chacha_x(key: &[u8; 32], nonce: &[u8; 24], rounds: u32) -> ChaCha { + let key0: Mach::u32x4 = m.read_le(&key[..16]); + let key1: Mach::u32x4 = m.read_le(&key[16..]); + let nonce0: Mach::u32x4 = m.read_le(&nonce[..16]); + let mut state = ChaCha { + b: key0.into(), + c: key1.into(), + d: nonce0.into(), + }; + let x = refill_narrow_rounds(&mut state, rounds); + let ctr_nonce1 = [0, 0, read_u32le(&nonce[16..20]), read_u32le(&nonce[20..24])]; + state.b = x.a; + state.c = x.d; + state.d = ctr_nonce1.into(); + state + } +}); diff --git a/rand_chacha/src/lib.rs b/rand_chacha/src/lib.rs new file mode 100644 index 00000000..24ddd601 --- /dev/null +++ b/rand_chacha/src/lib.rs @@ -0,0 +1,106 @@ +// Copyright 2018 Developers of the Rand project. +// +// 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 generators. +//! +//! These are native Rust implementations of RNGs derived from the +//! [ChaCha stream ciphers] by D J Bernstein. +//! +//! ## Generators +//! +//! This crate provides 8-, 12- and 20-round variants of generators via a "core" +//! implementation (of [`BlockRngCore`]), each with an associated "RNG" type +//! (implementing [`RngCore`]). +//! +//! These generators are all deterministic and portable (see [Reproducibility] +//! in the book), with testing against reference vectors. +//! +//! ## Cryptographic (secure) usage +//! +//! Where secure unpredictable generators are required, it is suggested to use +//! [`ChaCha12Rng`] or [`ChaCha20Rng`] and to seed via +//! [`SeedableRng::from_os_rng`]. +//! +//! See also the [Security] chapter in the rand book. The crate is provided +//! "as is", without any form of guarantee, and without a security audit. +//! +//! ## Seeding (construction) +//! +//! Generators implement the [`SeedableRng`] trait. Any method may be used, +//! but note that `seed_from_u64` is not suitable for usage where security is +//! important. Some suggestions: +//! +//! 1. With a fresh seed, **direct from the OS** (implies a syscall): +//! ``` +//! # use {rand_core::SeedableRng, rand_chacha::ChaCha12Rng}; +//! let rng = ChaCha12Rng::from_os_rng(); +//! # let _: ChaCha12Rng = rng; +//! ``` +//! 2. **From a master generator.** This could be [`rand::rng`] +//! (effectively a fresh seed without the need for a syscall on each usage) +//! or a deterministic generator such as [`ChaCha20Rng`]. +//! Beware that should a weak master generator be used, correlations may be +//! detectable between the outputs of its child generators. +//! ```ignore +//! let rng = ChaCha12Rng::from_rng(&mut rand::rng()); +//! ``` +//! +//! See also [Seeding RNGs] in the book. +//! +//! ## Generation +//! +//! Generators implement [`RngCore`], whose methods may be used directly to +//! generate unbounded integer or byte values. +//! ``` +//! use rand_core::{SeedableRng, RngCore}; +//! use rand_chacha::ChaCha12Rng; +//! +//! let mut rng = ChaCha12Rng::from_seed(Default::default()); +//! let x = rng.next_u64(); +//! assert_eq!(x, 0x53f955076a9af49b); +//! ``` +//! +//! It is often more convenient to use the [`rand::Rng`] trait, which provides +//! further functionality. See also the [Random Values] chapter in the book. +//! +//! [ChaCha stream ciphers]: https://cr.yp.to/chacha.html +//! [Reproducibility]: https://rust-random.github.io/book/crate-reprod.html +//! [Seeding RNGs]: https://rust-random.github.io/book/guide-seeding.html +//! [Security]: https://rust-random.github.io/book/guide-rngs.html#security +//! [Random Values]: https://rust-random.github.io/book/guide-values.html +//! [`BlockRngCore`]: rand_core::block::BlockRngCore +//! [`RngCore`]: rand_core::RngCore +//! [`SeedableRng`]: rand_core::SeedableRng +//! [`SeedableRng::from_os_rng`]: rand_core::SeedableRng::from_os_rng +//! [`rand::rng`]: https://docs.rs/rand/latest/rand/fn.rng.html +//! [`rand::Rng`]: https://docs.rs/rand/latest/rand/trait.Rng.html + +#![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/" +)] +#![forbid(unsafe_code)] +#![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; +mod guts; + +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; From 15c246ef21b48fd5bd4e326e6519cf4e394114b7 Mon Sep 17 00:00:00 2001 From: Diggory Hardy Date: Wed, 10 Sep 2025 08:17:07 +0100 Subject: [PATCH 2/5] Add comment to the README. --- rand_chacha/README.md | 3 +++ 1 file changed, 3 insertions(+) diff --git a/rand_chacha/README.md b/rand_chacha/README.md index 167417f8..19cfafac 100644 --- a/rand_chacha/README.md +++ b/rand_chacha/README.md @@ -9,6 +9,9 @@ A cryptographically secure random number generator that uses the ChaCha algorithm. +This implementation of ChaCha RNGs is built over `ppv-lite86` by Kaz Wesley, +and was formerly the implementation behind `rand::rngs::StdRng`. + 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 From 945d4037e66e0a0928f10117451f6a7e43da649c Mon Sep 17 00:00:00 2001 From: Diggory Hardy Date: Wed, 10 Sep 2025 08:18:22 +0100 Subject: [PATCH 3/5] Add to CI tests --- .github/workflows/test.yml | 3 +++ 1 file changed, 3 insertions(+) diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml index 209850cd..267274a9 100644 --- a/.github/workflows/test.yml +++ b/.github/workflows/test.yml @@ -78,6 +78,7 @@ jobs: cargo test --target ${{ matrix.target }} --benches - name: Test run: | + cargo test --target ${{ matrix.target }} --manifest-path rand_chacha/Cargo.toml --all-features cargo test --target ${{ matrix.target }} --manifest-path rand_hc/Cargo.toml --all-features cargo test --target ${{ matrix.target }} --manifest-path rand_isaac/Cargo.toml --all-features cargo test --target ${{ matrix.target }} --manifest-path rand_xorshift/Cargo.toml --all-features @@ -108,6 +109,7 @@ jobs: run: cargo install cross || true - name: Test run: | + cross test --no-fail-fast --target ${{ matrix.target }} --manifest-path rand_chacha/Cargo.toml --all-features cross test --no-fail-fast --target ${{ matrix.target }} --manifest-path rand_hc/Cargo.toml --all-features cross test --no-fail-fast --target ${{ matrix.target }} --manifest-path rand_isaac/Cargo.toml --all-features cross test --no-fail-fast --target ${{ matrix.target }} --manifest-path rand_xorshift/Cargo.toml --all-features @@ -125,6 +127,7 @@ jobs: rustup component add miri - name: Test rand run: | + cargo miri test --manifest-path rand_chacha/Cargo.toml --all-features cargo miri test --manifest-path rand_hc/Cargo.toml --all-features cargo miri test --manifest-path rand_isaac/Cargo.toml --all-features cargo miri test --manifest-path rand_xorshift/Cargo.toml --all-features From 5bb72aced699f042eebe71046688221ae516042b Mon Sep 17 00:00:00 2001 From: Diggory Hardy Date: Wed, 10 Sep 2025 08:21:04 +0100 Subject: [PATCH 4/5] Add ChaCha RNGs to benchmarks --- benches/Cargo.toml | 1 + benches/mod.rs | 13 +++++++++++++ 2 files changed, 14 insertions(+) diff --git a/benches/Cargo.toml b/benches/Cargo.toml index d6bcd302..92aa9559 100644 --- a/benches/Cargo.toml +++ b/benches/Cargo.toml @@ -9,6 +9,7 @@ publish = false criterion = "0.5.0" criterion-cycles-per-byte = "0.6" rand_core = { version = "0.9.0", features = ["os_rng"] } +rand_chacha = { path = "../rand_chacha", version = "0.9" } rand_xoshiro = { path = "../rand_xoshiro", version = "0.7" } rand_isaac = { path = "../rand_isaac", version = "0.4" } rand_xorshift = { path = "../rand_xorshift", version = "0.4" } diff --git a/benches/mod.rs b/benches/mod.rs index 7a4ce084..f83578c1 100644 --- a/benches/mod.rs +++ b/benches/mod.rs @@ -18,6 +18,7 @@ use criterion::{criterion_group, criterion_main, Criterion, Throughput}; use criterion_cycles_per_byte::CyclesPerByte; use rand_core::{RngCore, SeedableRng}; +use rand_chacha::{ChaCha12Rng, ChaCha20Rng, ChaCha8Rng}; use rand_hc::Hc128Rng; use rand_isaac::{Isaac64Rng, IsaacRng}; use rand_xorshift::XorShiftRng; @@ -64,6 +65,9 @@ fn gen_bytes(c: &mut Criterion) { gen_bytes!("hc128", Hc128Rng::from_os_rng()); gen_bytes!("isaac", IsaacRng::from_os_rng()); gen_bytes!("isaac64", Isaac64Rng::from_os_rng()); + gen_bytes!("chacha8", ChaCha8Rng::from_os_rng()); + gen_bytes!("chacha12", ChaCha12Rng::from_os_rng()); + gen_bytes!("chacha20", ChaCha20Rng::from_os_rng()); } // Save a dependency on Rand: @@ -150,6 +154,9 @@ fn gen_uint(c: &mut Criterion) { gen_uint!(g, "hc128", u32, Hc128Rng::from_os_rng()); gen_uint!(g, "isaac", u32, IsaacRng::from_os_rng()); gen_uint!(g, "isaac64", u32, Isaac64Rng::from_os_rng()); + gen_uint!(g, "chacha8", u32, ChaCha8Rng::from_os_rng()); + gen_uint!(g, "chacha12", u32, ChaCha12Rng::from_os_rng()); + gen_uint!(g, "chacha20", u32, ChaCha20Rng::from_os_rng()); } { @@ -201,6 +208,9 @@ fn gen_uint(c: &mut Criterion) { gen_uint!(g, "hc128", u64, Hc128Rng::from_os_rng()); gen_uint!(g, "isaac", u64, IsaacRng::from_os_rng()); gen_uint!(g, "isaac64", u64, Isaac64Rng::from_os_rng()); + gen_uint!(g, "chacha8", u64, ChaCha8Rng::from_os_rng()); + gen_uint!(g, "chacha12", u64, ChaCha12Rng::from_os_rng()); + gen_uint!(g, "chacha20", u64, ChaCha20Rng::from_os_rng()); } } @@ -231,6 +241,9 @@ fn init(c: &mut Criterion) { init_gen!("hc128", Hc128Rng); init_gen!("isaac", IsaacRng); init_gen!("isaac64", Isaac64Rng); + init_gen!("chacha8", ChaCha8Rng); + init_gen!("chacha12", ChaCha12Rng); + init_gen!("chacha20", ChaCha20Rng); } criterion_group! { From 2836670d5402d51c0f51a8cd5b8331b0d6c2ef9d Mon Sep 17 00:00:00 2001 From: Diggory Hardy Date: Wed, 10 Sep 2025 08:33:43 +0100 Subject: [PATCH 5/5] Remove patch.crates-io.rand_core for benches --- benches/Cargo.toml | 4 ---- 1 file changed, 4 deletions(-) diff --git a/benches/Cargo.toml b/benches/Cargo.toml index 92aa9559..9c8df5a2 100644 --- a/benches/Cargo.toml +++ b/benches/Cargo.toml @@ -19,7 +19,3 @@ rand_hc = { path = "../rand_hc", version = "0.4" } name = "mod" path = "mod.rs" harness = false - -[patch.crates-io.rand_core] -git = "https://github.com/rust-random/rand.git" -branch = "master"