const BLOCK_SIZE: usize = 128;
const RESULT_SIZE: usize = 64;
const STATE_SIZE: usize = 8;
const INIT_STATE: [u64; STATE_SIZE] = [
0x6a09e667f3bcc908,
0xbb67ae8584caa73b,
0x3c6ef372fe94f82b,
0xa54ff53a5f1d36f1,
0x510e527fade682d1,
0x9b05688c2b3e6c1f,
0x1f83d9abfb41bd6b,
0x5be0cd19137e2179,
];
const K512: [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,
];
const fn sha512_transform(
state: [u64; STATE_SIZE],
cursor: usize,
input: &[u8],
) -> [u64; STATE_SIZE] {
let mut a = state[0];
let mut b = state[1];
let mut c = state[2];
let mut d = state[3];
let mut e = state[4];
let mut f = state[5];
let mut g = state[6];
let mut h = state[7];
macro_rules! S0 {
($in:expr) => {
(($in.rotate_right(5) ^ $in).rotate_right(6) ^ $in).rotate_right(28)
};
}
macro_rules! S1 {
($in:expr) => {
(($in.rotate_right(23) ^ $in).rotate_right(4) ^ $in).rotate_right(14)
};
}
macro_rules! s0 {
($in:expr) => {
($in.rotate_right(7) ^ $in).rotate_right(1) ^ $in.wrapping_shr(7)
};
}
macro_rules! s1 {
($in:expr) => {
($in.rotate_right(42) ^ $in).rotate_right(19) ^ $in.wrapping_shr(6)
};
}
macro_rules! Ch {
($x:expr, $y:expr, $z:expr) => {
(($z) ^ (($x) & (($y) ^ ($z))))
};
}
macro_rules! Ma {
($x:expr, $y:expr, $z:expr) => {
((($x) & ($y)) | (($z) & (($x) | ($y))))
};
}
const fn read_u64(input: &[u8], cursor: usize) -> u64 {
u64::from_be_bytes([
input[cursor],
input[cursor + 1],
input[cursor + 2],
input[cursor + 3],
input[cursor + 4],
input[cursor + 5],
input[cursor + 6],
input[cursor + 7],
])
}
let mut x = [0u64; 80];
let mut idx = 0;
while idx < 16 {
x[idx] = read_u64(input, cursor + idx * 8);
idx += 1;
}
while idx < x.len() {
x[idx] = s1!(x[idx - 2])
.wrapping_add(x[idx - 7])
.wrapping_add(s0!(x[idx - 15]))
.wrapping_add(x[idx - 16]);
idx += 1;
}
macro_rules! R {
($a:expr, $b:expr, $c:expr, $d:expr, $e:expr, $f:expr, $g:expr, $h:expr, $i:expr) => {
$h = $h.wrapping_add(
S1!($e)
.wrapping_add(Ch!($e, $f, $g))
.wrapping_add(K512[$i])
.wrapping_add(x[$i]),
);
$d = $d.wrapping_add($h);
$h = $h.wrapping_add(S0!($a).wrapping_add(Ma!($a, $b, $c)));
};
}
idx = 0;
while idx < 80 {
R!(a, b, c, d, e, f, g, h, idx);
R!(h, a, b, c, d, e, f, g, idx + 1);
R!(g, h, a, b, c, d, e, f, idx + 2);
R!(f, g, h, a, b, c, d, e, idx + 3);
R!(e, f, g, h, a, b, c, d, idx + 4);
R!(d, e, f, g, h, a, b, c, idx + 5);
R!(c, d, e, f, g, h, a, b, idx + 6);
R!(b, c, d, e, f, g, h, a, idx + 7);
idx += 8;
}
[
state[0].wrapping_add(a),
state[1].wrapping_add(b),
state[2].wrapping_add(c),
state[3].wrapping_add(d),
state[4].wrapping_add(e),
state[5].wrapping_add(f),
state[6].wrapping_add(g),
state[7].wrapping_add(h),
]
}
pub const fn sha512(input: &[u8]) -> [u8; RESULT_SIZE] {
let mut state = INIT_STATE;
let mut cursor = 0;
while cursor + BLOCK_SIZE <= input.len() {
state = sha512_transform(state, cursor, input);
cursor += BLOCK_SIZE;
}
let mut pos = 0;
let mut buffer = [0; BLOCK_SIZE];
while pos < input.len() - cursor {
buffer[pos] = input[cursor + pos];
pos += 1;
}
buffer[pos] = 0x80;
pos += 1;
while pos != (BLOCK_SIZE - (2 * core::mem::size_of::<u64>())) {
pos &= BLOCK_SIZE - 1;
if pos == 0 {
state = sha512_transform(state, 0, &buffer);
}
buffer[pos] = 0;
pos += 1;
}
let input_len = input.len() as u64;
let len_lo = input_len.wrapping_shl(3).to_be_bytes();
let len_hi = input_len.wrapping_shr(64 - 3).to_be_bytes();
buffer[pos] = len_hi[0];
buffer[pos + 1] = len_hi[1];
buffer[pos + 2] = len_hi[2];
buffer[pos + 3] = len_hi[3];
buffer[pos + 4] = len_hi[4];
buffer[pos + 5] = len_hi[5];
buffer[pos + 6] = len_hi[6];
buffer[pos + 7] = len_hi[7];
buffer[pos + 8] = len_lo[0];
buffer[pos + 9] = len_lo[1];
buffer[pos + 10] = len_lo[2];
buffer[pos + 11] = len_lo[3];
buffer[pos + 12] = len_lo[4];
buffer[pos + 13] = len_lo[5];
buffer[pos + 14] = len_lo[6];
buffer[pos + 15] = len_lo[7];
state = sha512_transform(state, 0, &buffer);
let a = state[0].to_be_bytes();
let b = state[1].to_be_bytes();
let c = state[2].to_be_bytes();
let d = state[3].to_be_bytes();
let e = state[4].to_be_bytes();
let f = state[5].to_be_bytes();
let g = state[6].to_be_bytes();
let h = state[7].to_be_bytes();
[
a[0], a[1], a[2], a[3], a[4], a[5], a[6], a[7], b[0], b[1], b[2], b[3], b[4], b[5], b[6],
b[7], c[0], c[1], c[2], c[3], c[4], c[5], c[6], c[7], d[0], d[1], d[2], d[3], d[4], d[5],
d[6], d[7], e[0], e[1], e[2], e[3], e[4], e[5], e[6], e[7], f[0], f[1], f[2], f[3], f[4],
f[5], f[6], f[7], g[0], g[1], g[2], g[3], g[4], g[5], g[6], g[7], h[0], h[1], h[2], h[3],
h[4], h[5], h[6], h[7],
]
}