const K: [u64; 80] = [
0x428a2f98d728ae22,
0x7137449123ef65cd,
0xb5c0fbcfec4d3b2f,
0xe9b5dba58189dbbc,
0x3956c25bf348b538,
0x59f111f1b605d019,
0x923f82a4af194f9b,
0xab1c5ed5da6d8118,
0xd807aa98a3030242,
0x12835b0145706fbe,
0x243185be4ee4b28c,
0x550c7dc3d5ffb4e2,
0x72be5d74f27b896f,
0x80deb1fe3b1696b1,
0x9bdc06a725c71235,
0xc19bf174cf692694,
0xe49b69c19ef14ad2,
0xefbe4786384f25e3,
0x0fc19dc68b8cd5b5,
0x240ca1cc77ac9c65,
0x2de92c6f592b0275,
0x4a7484aa6ea6e483,
0x5cb0a9dcbd41fbd4,
0x76f988da831153b5,
0x983e5152ee66dfab,
0xa831c66d2db43210,
0xb00327c898fb213f,
0xbf597fc7beef0ee4,
0xc6e00bf33da88fc2,
0xd5a79147930aa725,
0x06ca6351e003826f,
0x142929670a0e6e70,
0x27b70a8546d22ffc,
0x2e1b21385c26c926,
0x4d2c6dfc5ac42aed,
0x53380d139d95b3df,
0x650a73548baf63de,
0x766a0abb3c77b2a8,
0x81c2c92e47edaee6,
0x92722c851482353b,
0xa2bfe8a14cf10364,
0xa81a664bbc423001,
0xc24b8b70d0f89791,
0xc76c51a30654be30,
0xd192e819d6ef5218,
0xd69906245565a910,
0xf40e35855771202a,
0x106aa07032bbd1b8,
0x19a4c116b8d2d0c8,
0x1e376c085141ab53,
0x2748774cdf8eeb99,
0x34b0bcb5e19b48a8,
0x391c0cb3c5c95a63,
0x4ed8aa4ae3418acb,
0x5b9cca4f7763e373,
0x682e6ff3d6b2b8a3,
0x748f82ee5defb2fc,
0x78a5636f43172f60,
0x84c87814a1f0ab72,
0x8cc702081a6439ec,
0x90befffa23631e28,
0xa4506cebde82bde9,
0xbef9a3f7b2c67915,
0xc67178f2e372532b,
0xca273eceea26619c,
0xd186b8c721c0c207,
0xeada7dd6cde0eb1e,
0xf57d4f7fee6ed178,
0x06f067aa72176fba,
0x0a637dc5a2c898a6,
0x113f9804bef90dae,
0x1b710b35131c471b,
0x28db77f523047d84,
0x32caab7b40c72493,
0x3c9ebe0a15c9bebc,
0x431d67c49c100d4c,
0x4cc5d4becb3e42b6,
0x597f299cfc657e2a,
0x5fcb6fab3ad6faec,
0x6c44198c4a475817,
];
#[derive(Clone)]
pub struct Sha512 {
state: [u64; 8],
len: u128,
block: [u8; 128],
n: usize,
}
impl Default for Sha512 {
fn default() -> Self {
Self::new()
}
}
impl Sha512 {
pub fn new() -> Self {
Sha512 {
state: [
0x6a09e667f3bcc908,
0xbb67ae8584caa73b,
0x3c6ef372fe94f82b,
0xa54ff53a5f1d36f1,
0x510e527fade682d1,
0x9b05688c2b3e6c1f,
0x1f83d9abfb41bd6b,
0x5be0cd19137e2179,
],
len: 0,
block: [0u8; 128],
n: 0,
}
}
pub fn update(&mut self, data: &[u8]) {
self.len = self.len.wrapping_add(data.len() as u128);
let mut off = 0usize;
if self.n > 0 && self.n + data.len() >= 128 {
let take = 128 - self.n;
self.block[self.n..].copy_from_slice(&data[..take]);
compress(&mut self.state, &self.block);
self.n = 0;
off = take;
}
while off + 128 <= data.len() {
let mut b = [0u8; 128];
b.copy_from_slice(&data[off..off + 128]);
compress(&mut self.state, &b);
off += 128;
}
let rem = data.len() - off;
if rem > 0 {
self.block[self.n..self.n + rem].copy_from_slice(&data[off..]);
self.n += rem;
}
}
pub fn finalize(mut self) -> [u8; 64] {
let bit_len = self.len.wrapping_mul(8);
self.update(&[0x80]);
while self.n != 112 {
self.update(&[0]);
}
self.block[112..128].copy_from_slice(&bit_len.to_be_bytes());
compress(&mut self.state, &self.block);
let mut out = [0u8; 64];
for (i, s) in self.state.iter().enumerate() {
out[i * 8..i * 8 + 8].copy_from_slice(&s.to_be_bytes());
}
out
}
pub fn digest(data: &[u8]) -> [u8; 64] {
let mut h = Sha512::new();
h.update(data);
h.finalize()
}
}
fn compress(state: &mut [u64; 8], block: &[u8; 128]) {
let mut w = [0u64; 80];
for i in 0..16 {
let mut b = [0u8; 8];
b.copy_from_slice(&block[i * 8..i * 8 + 8]);
w[i] = u64::from_be_bytes(b);
}
for i in 16..80 {
let s0 = w[i - 15].rotate_right(1) ^ w[i - 15].rotate_right(8) ^ (w[i - 15] >> 7);
let s1 = w[i - 2].rotate_right(19) ^ w[i - 2].rotate_right(61) ^ (w[i - 2] >> 6);
w[i] = w[i - 16]
.wrapping_add(s0)
.wrapping_add(w[i - 7])
.wrapping_add(s1);
}
let (mut a, mut b, mut c, mut d, mut e, mut f, mut g, mut h) = (
state[0], state[1], state[2], state[3], state[4], state[5], state[6], state[7],
);
for i in 0..80 {
let s1 = e.rotate_right(14) ^ e.rotate_right(18) ^ e.rotate_right(41);
let ch = (e & f) ^ ((!e) & g);
let t1 = h
.wrapping_add(s1)
.wrapping_add(ch)
.wrapping_add(K[i])
.wrapping_add(w[i]);
let s0 = a.rotate_right(28) ^ a.rotate_right(34) ^ a.rotate_right(39);
let maj = (a & b) ^ (a & c) ^ (b & c);
let t2 = s0.wrapping_add(maj);
h = g;
g = f;
f = e;
e = d.wrapping_add(t1);
d = c;
c = b;
b = a;
a = t1.wrapping_add(t2);
}
state[0] = state[0].wrapping_add(a);
state[1] = state[1].wrapping_add(b);
state[2] = state[2].wrapping_add(c);
state[3] = state[3].wrapping_add(d);
state[4] = state[4].wrapping_add(e);
state[5] = state[5].wrapping_add(f);
state[6] = state[6].wrapping_add(g);
state[7] = state[7].wrapping_add(h);
}
#[cfg(test)]
mod tests {
use super::*;
use alloc::string::String;
fn hex(d: [u8; 64]) -> String {
let mut s = String::new();
for b in d {
s.push_str(&format!("{:02x}", b));
}
s
}
#[test]
fn fips_vectors() {
assert_eq!(
hex(Sha512::digest(b"abc")),
"ddaf35a193617abacc417349ae20413112e6fa4e89a97ea20a9eeee64b55d39a\
2192992a274fc1a836ba3c23a3feebbd454d4423643ce80e2a9ac94fa54ca49f"
.replace(' ', "")
);
assert_eq!(
hex(Sha512::digest(b"")),
"cf83e1357eefb8bdf1542850d66d8007d620e4050b5715dc83f4a921d36ce9ce\
47d0d13c5d85f2b0ff8318d2877eec2f63b931bd47417a81a538327af927da3e"
.replace(' ', "")
);
}
}