rust-bitcoin-unsafe-fast/hashes/src/siphash24.rs

387 lines
13 KiB
Rust

// SPDX-License-Identifier: CC0-1.0
//! SipHash 2-4 implementation.
//!
use core::ops::Index;
use core::slice::SliceIndex;
use core::{cmp, mem, ptr, str};
use crate::{FromSliceError, Hash as _, HashEngine as _};
crate::internal_macros::hash_type! {
64,
false,
"Output of the SipHash24 hash function."
}
#[cfg(not(hashes_fuzz))]
fn from_engine(e: HashEngine) -> Hash { Hash::from_u64(Hash::from_engine_to_u64(e)) }
#[cfg(hashes_fuzz)]
fn from_engine(e: HashEngine) -> Hash {
let state = e.midstate();
Hash::from_u64(state.v0 ^ state.v1 ^ state.v2 ^ state.v3)
}
macro_rules! compress {
($state:expr) => {{
compress!($state.v0, $state.v1, $state.v2, $state.v3)
}};
($v0:expr, $v1:expr, $v2:expr, $v3:expr) => {{
$v0 = $v0.wrapping_add($v1);
$v1 = $v1.rotate_left(13);
$v1 ^= $v0;
$v0 = $v0.rotate_left(32);
$v2 = $v2.wrapping_add($v3);
$v3 = $v3.rotate_left(16);
$v3 ^= $v2;
$v0 = $v0.wrapping_add($v3);
$v3 = $v3.rotate_left(21);
$v3 ^= $v0;
$v2 = $v2.wrapping_add($v1);
$v1 = $v1.rotate_left(17);
$v1 ^= $v2;
$v2 = $v2.rotate_left(32);
}};
}
/// Load an integer of the desired type from a byte stream, in LE order. Uses
/// `copy_nonoverlapping` to let the compiler generate the most efficient way
/// to load it from a possibly unaligned address.
///
/// Unsafe because: unchecked indexing at `i..i+size_of(int_ty)`.
macro_rules! load_int_le {
($buf:expr, $i:expr, $int_ty:ident) => {{
debug_assert!($i + mem::size_of::<$int_ty>() <= $buf.len());
let mut data = 0 as $int_ty;
ptr::copy_nonoverlapping(
$buf.get_unchecked($i),
&mut data as *mut _ as *mut u8,
mem::size_of::<$int_ty>(),
);
data.to_le()
}};
}
/// Internal state of the [`HashEngine`].
#[derive(Debug, Clone)]
pub struct State {
// v0, v2 and v1, v3 show up in pairs in the algorithm,
// and simd implementations of SipHash will use vectors
// of v02 and v13. By placing them in this order in the struct,
// the compiler can pick up on just a few simd optimizations by itself.
v0: u64,
v2: u64,
v1: u64,
v3: u64,
}
/// Engine to compute the SipHash24 hash function.
#[derive(Debug, Clone)]
pub struct HashEngine {
k0: u64,
k1: u64,
length: usize, // how many bytes we've processed
state: State, // hash State
tail: u64, // unprocessed bytes le
ntail: usize, // how many bytes in tail are valid
}
impl HashEngine {
/// Creates a new SipHash24 engine with keys.
pub fn with_keys(k0: u64, k1: u64) -> HashEngine {
HashEngine {
k0,
k1,
length: 0,
state: State {
v0: k0 ^ 0x736f6d6570736575,
v1: k1 ^ 0x646f72616e646f6d,
v2: k0 ^ 0x6c7967656e657261,
v3: k1 ^ 0x7465646279746573,
},
tail: 0,
ntail: 0,
}
}
/// Creates a new SipHash24 engine.
pub fn new() -> HashEngine { HashEngine::with_keys(0, 0) }
/// Retrieves the keys of this engine.
pub fn keys(&self) -> (u64, u64) { (self.k0, self.k1) }
#[inline]
fn c_rounds(state: &mut State) {
compress!(state);
compress!(state);
}
#[inline]
fn d_rounds(state: &mut State) {
compress!(state);
compress!(state);
compress!(state);
compress!(state);
}
}
impl Default for HashEngine {
fn default() -> Self { HashEngine::new() }
}
impl crate::HashEngine for HashEngine {
type MidState = State;
fn midstate(&self) -> State { self.state.clone() }
const BLOCK_SIZE: usize = 8;
#[inline]
fn input(&mut self, msg: &[u8]) {
let length = msg.len();
self.length += length;
let mut needed = 0;
if self.ntail != 0 {
needed = 8 - self.ntail;
self.tail |= unsafe { u8to64_le(msg, 0, cmp::min(length, needed)) } << (8 * self.ntail);
if length < needed {
self.ntail += length;
return;
} else {
self.state.v3 ^= self.tail;
HashEngine::c_rounds(&mut self.state);
self.state.v0 ^= self.tail;
self.ntail = 0;
}
}
// Buffered tail is now flushed, process new input.
let len = length - needed;
let left = len & 0x7;
let mut i = needed;
while i < len - left {
let mi = unsafe { load_int_le!(msg, i, u64) };
self.state.v3 ^= mi;
HashEngine::c_rounds(&mut self.state);
self.state.v0 ^= mi;
i += 8;
}
self.tail = unsafe { u8to64_le(msg, i, left) };
self.ntail = left;
}
fn n_bytes_hashed(&self) -> usize { self.length }
}
impl Hash {
/// Hashes the given data with an engine with the provided keys.
pub fn hash_with_keys(k0: u64, k1: u64, data: &[u8]) -> Hash {
let mut engine = HashEngine::with_keys(k0, k1);
engine.input(data);
Hash::from_engine(engine)
}
/// Hashes the given data directly to u64 with an engine with the provided keys.
pub fn hash_to_u64_with_keys(k0: u64, k1: u64, data: &[u8]) -> u64 {
let mut engine = HashEngine::with_keys(k0, k1);
engine.input(data);
Hash::from_engine_to_u64(engine)
}
/// Produces a hash as `u64` from the current state of a given engine.
#[inline]
pub fn from_engine_to_u64(e: HashEngine) -> u64 {
let mut state = e.state;
let b: u64 = ((e.length as u64 & 0xff) << 56) | e.tail;
state.v3 ^= b;
HashEngine::c_rounds(&mut state);
state.v0 ^= b;
state.v2 ^= 0xff;
HashEngine::d_rounds(&mut state);
state.v0 ^ state.v1 ^ state.v2 ^ state.v3
}
/// Returns the (little endian) 64-bit integer representation of the hash value.
pub fn as_u64(&self) -> u64 { u64::from_le_bytes(self.0) }
/// Creates a hash from its (little endian) 64-bit integer representation.
pub fn from_u64(hash: u64) -> Hash { Hash(hash.to_le_bytes()) }
}
/// Load an u64 using up to 7 bytes of a byte slice.
///
/// Unsafe because: unchecked indexing at `start..start+len`.
#[inline]
unsafe fn u8to64_le(buf: &[u8], start: usize, len: usize) -> u64 {
debug_assert!(len < 8);
let mut i = 0; // current byte index (from LSB) in the output u64
let mut out = 0;
if i + 3 < len {
out = u64::from(load_int_le!(buf, start + i, u32));
i += 4;
}
if i + 1 < len {
out |= u64::from(load_int_le!(buf, start + i, u16)) << (i * 8);
i += 2
}
if i < len {
out |= u64::from(*buf.get_unchecked(start + i)) << (i * 8);
i += 1;
}
debug_assert_eq!(i, len);
out
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn test_siphash_2_4() {
#[rustfmt::skip]
let vecs: [[u8; 8]; 64] = [
[0x31, 0x0e, 0x0e, 0xdd, 0x47, 0xdb, 0x6f, 0x72],
[0xfd, 0x67, 0xdc, 0x93, 0xc5, 0x39, 0xf8, 0x74],
[0x5a, 0x4f, 0xa9, 0xd9, 0x09, 0x80, 0x6c, 0x0d],
[0x2d, 0x7e, 0xfb, 0xd7, 0x96, 0x66, 0x67, 0x85],
[0xb7, 0x87, 0x71, 0x27, 0xe0, 0x94, 0x27, 0xcf],
[0x8d, 0xa6, 0x99, 0xcd, 0x64, 0x55, 0x76, 0x18],
[0xce, 0xe3, 0xfe, 0x58, 0x6e, 0x46, 0xc9, 0xcb],
[0x37, 0xd1, 0x01, 0x8b, 0xf5, 0x00, 0x02, 0xab],
[0x62, 0x24, 0x93, 0x9a, 0x79, 0xf5, 0xf5, 0x93],
[0xb0, 0xe4, 0xa9, 0x0b, 0xdf, 0x82, 0x00, 0x9e],
[0xf3, 0xb9, 0xdd, 0x94, 0xc5, 0xbb, 0x5d, 0x7a],
[0xa7, 0xad, 0x6b, 0x22, 0x46, 0x2f, 0xb3, 0xf4],
[0xfb, 0xe5, 0x0e, 0x86, 0xbc, 0x8f, 0x1e, 0x75],
[0x90, 0x3d, 0x84, 0xc0, 0x27, 0x56, 0xea, 0x14],
[0xee, 0xf2, 0x7a, 0x8e, 0x90, 0xca, 0x23, 0xf7],
[0xe5, 0x45, 0xbe, 0x49, 0x61, 0xca, 0x29, 0xa1],
[0xdb, 0x9b, 0xc2, 0x57, 0x7f, 0xcc, 0x2a, 0x3f],
[0x94, 0x47, 0xbe, 0x2c, 0xf5, 0xe9, 0x9a, 0x69],
[0x9c, 0xd3, 0x8d, 0x96, 0xf0, 0xb3, 0xc1, 0x4b],
[0xbd, 0x61, 0x79, 0xa7, 0x1d, 0xc9, 0x6d, 0xbb],
[0x98, 0xee, 0xa2, 0x1a, 0xf2, 0x5c, 0xd6, 0xbe],
[0xc7, 0x67, 0x3b, 0x2e, 0xb0, 0xcb, 0xf2, 0xd0],
[0x88, 0x3e, 0xa3, 0xe3, 0x95, 0x67, 0x53, 0x93],
[0xc8, 0xce, 0x5c, 0xcd, 0x8c, 0x03, 0x0c, 0xa8],
[0x94, 0xaf, 0x49, 0xf6, 0xc6, 0x50, 0xad, 0xb8],
[0xea, 0xb8, 0x85, 0x8a, 0xde, 0x92, 0xe1, 0xbc],
[0xf3, 0x15, 0xbb, 0x5b, 0xb8, 0x35, 0xd8, 0x17],
[0xad, 0xcf, 0x6b, 0x07, 0x63, 0x61, 0x2e, 0x2f],
[0xa5, 0xc9, 0x1d, 0xa7, 0xac, 0xaa, 0x4d, 0xde],
[0x71, 0x65, 0x95, 0x87, 0x66, 0x50, 0xa2, 0xa6],
[0x28, 0xef, 0x49, 0x5c, 0x53, 0xa3, 0x87, 0xad],
[0x42, 0xc3, 0x41, 0xd8, 0xfa, 0x92, 0xd8, 0x32],
[0xce, 0x7c, 0xf2, 0x72, 0x2f, 0x51, 0x27, 0x71],
[0xe3, 0x78, 0x59, 0xf9, 0x46, 0x23, 0xf3, 0xa7],
[0x38, 0x12, 0x05, 0xbb, 0x1a, 0xb0, 0xe0, 0x12],
[0xae, 0x97, 0xa1, 0x0f, 0xd4, 0x34, 0xe0, 0x15],
[0xb4, 0xa3, 0x15, 0x08, 0xbe, 0xff, 0x4d, 0x31],
[0x81, 0x39, 0x62, 0x29, 0xf0, 0x90, 0x79, 0x02],
[0x4d, 0x0c, 0xf4, 0x9e, 0xe5, 0xd4, 0xdc, 0xca],
[0x5c, 0x73, 0x33, 0x6a, 0x76, 0xd8, 0xbf, 0x9a],
[0xd0, 0xa7, 0x04, 0x53, 0x6b, 0xa9, 0x3e, 0x0e],
[0x92, 0x59, 0x58, 0xfc, 0xd6, 0x42, 0x0c, 0xad],
[0xa9, 0x15, 0xc2, 0x9b, 0xc8, 0x06, 0x73, 0x18],
[0x95, 0x2b, 0x79, 0xf3, 0xbc, 0x0a, 0xa6, 0xd4],
[0xf2, 0x1d, 0xf2, 0xe4, 0x1d, 0x45, 0x35, 0xf9],
[0x87, 0x57, 0x75, 0x19, 0x04, 0x8f, 0x53, 0xa9],
[0x10, 0xa5, 0x6c, 0xf5, 0xdf, 0xcd, 0x9a, 0xdb],
[0xeb, 0x75, 0x09, 0x5c, 0xcd, 0x98, 0x6c, 0xd0],
[0x51, 0xa9, 0xcb, 0x9e, 0xcb, 0xa3, 0x12, 0xe6],
[0x96, 0xaf, 0xad, 0xfc, 0x2c, 0xe6, 0x66, 0xc7],
[0x72, 0xfe, 0x52, 0x97, 0x5a, 0x43, 0x64, 0xee],
[0x5a, 0x16, 0x45, 0xb2, 0x76, 0xd5, 0x92, 0xa1],
[0xb2, 0x74, 0xcb, 0x8e, 0xbf, 0x87, 0x87, 0x0a],
[0x6f, 0x9b, 0xb4, 0x20, 0x3d, 0xe7, 0xb3, 0x81],
[0xea, 0xec, 0xb2, 0xa3, 0x0b, 0x22, 0xa8, 0x7f],
[0x99, 0x24, 0xa4, 0x3c, 0xc1, 0x31, 0x57, 0x24],
[0xbd, 0x83, 0x8d, 0x3a, 0xaf, 0xbf, 0x8d, 0xb7],
[0x0b, 0x1a, 0x2a, 0x32, 0x65, 0xd5, 0x1a, 0xea],
[0x13, 0x50, 0x79, 0xa3, 0x23, 0x1c, 0xe6, 0x60],
[0x93, 0x2b, 0x28, 0x46, 0xe4, 0xd7, 0x06, 0x66],
[0xe1, 0x91, 0x5f, 0x5c, 0xb1, 0xec, 0xa4, 0x6c],
[0xf3, 0x25, 0x96, 0x5c, 0xa1, 0x6d, 0x62, 0x9f],
[0x57, 0x5f, 0xf2, 0x8e, 0x60, 0x38, 0x1b, 0xe5],
[0x72, 0x45, 0x06, 0xeb, 0x4c, 0x32, 0x8a, 0x95],
];
let k0 = 0x_07_06_05_04_03_02_01_00;
let k1 = 0x_0f_0e_0d_0c_0b_0a_09_08;
let mut vin = [0u8; 64];
let mut state_inc = HashEngine::with_keys(k0, k1);
for i in 0..64 {
vin[i] = i as u8;
let vec = Hash::from_slice(&vecs[i][..]).unwrap();
let out = Hash::hash_with_keys(k0, k1, &vin[0..i]);
assert_eq!(vec, out, "vec #{}", i);
let inc = Hash::from_engine(state_inc.clone());
assert_eq!(vec, inc, "vec #{}", i);
state_inc.input(&[i as u8]);
}
}
}
#[cfg(bench)]
mod benches {
use test::Bencher;
use crate::{siphash24, Hash, HashEngine};
#[bench]
pub fn siphash24_1ki(bh: &mut Bencher) {
let mut engine = siphash24::Hash::engine();
let bytes = [1u8; 1024];
bh.iter(|| {
engine.input(&bytes);
});
bh.bytes = bytes.len() as u64;
}
#[bench]
pub fn siphash24_64ki(bh: &mut Bencher) {
let mut engine = siphash24::Hash::engine();
let bytes = [1u8; 65536];
bh.iter(|| {
engine.input(&bytes);
});
bh.bytes = bytes.len() as u64;
}
#[bench]
pub fn siphash24_1ki_hash(bh: &mut Bencher) {
let k0 = 0x_07_06_05_04_03_02_01_00;
let k1 = 0x_0f_0e_0d_0c_0b_0a_09_08;
let bytes = [1u8; 1024];
bh.iter(|| {
let _ = siphash24::Hash::hash_with_keys(k0, k1, &bytes);
});
bh.bytes = bytes.len() as u64;
}
#[bench]
pub fn siphash24_1ki_hash_u64(bh: &mut Bencher) {
let k0 = 0x_07_06_05_04_03_02_01_00;
let k1 = 0x_0f_0e_0d_0c_0b_0a_09_08;
let bytes = [1u8; 1024];
bh.iter(|| {
let _ = siphash24::Hash::hash_to_u64_with_keys(k0, k1, &bytes);
});
bh.bytes = bytes.len() as u64;
}
}