use core::num::Wrapping;
use crate::constants::SHA512_LENGTH;
pub type Digest = [u8; SHA512_LENGTH];
#[allow(non_snake_case)]
fn R(w: Wrapping<u64>, n: usize) -> Wrapping<u64> {
(w >> n) | (w << (64 - n))
}
#[allow(non_snake_case)]
fn Ch(x: Wrapping<u64>, y: Wrapping<u64>, z: Wrapping<u64>) -> Wrapping<u64> {
(x & y) ^ (!x & z)
}
#[allow(non_snake_case)]
fn Maj(x: Wrapping<u64>, y: Wrapping<u64>, z: Wrapping<u64>) -> Wrapping<u64> {
(x & y) ^ (x & z) ^ (y & z)
}
#[allow(non_snake_case)]
fn Sigma0(x: Wrapping<u64>) -> Wrapping<u64> {
R(x, 28) ^ R(x, 34) ^ R(x, 39)
}
#[allow(non_snake_case)]
fn Sigma1(x: Wrapping<u64>) -> Wrapping<u64> {
R(x, 14) ^ R(x, 18) ^ R(x, 41)
}
fn sigma0(x: Wrapping<u64>) -> Wrapping<u64> {
R(x, 1) ^ R(x, 8) ^ (x >> 7)
}
fn sigma1(x: Wrapping<u64>) -> Wrapping<u64> {
R(x, 19) ^ R(x, 61) ^ (x >> 6)
}
#[rustfmt::skip]
static 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,
];
fn hash_blocks(digest: &mut [u8; 64], msg: &[u8]) -> usize {
#![allow(non_snake_case)]
let mut H: [Wrapping<u64>; 8] = Default::default(); for (h, chunk) in H.iter_mut().zip(digest.chunks(8)) {
*h = Wrapping(u64::from_be_bytes(chunk.try_into().unwrap()));
}
let unprocessed = msg.len() & 127; for block in msg[..msg.len() - unprocessed].chunks(128) {
let mut W: [Wrapping<u64>; 16] = Default::default(); for (w, chunk) in W.iter_mut().zip(block.chunks(8)) {
*w = Wrapping(u64::from_be_bytes(chunk.try_into().unwrap()));
}
let mut a = H[0];
let mut b = H[1];
let mut c = H[2];
let mut d = H[3];
let mut e = H[4];
let mut f = H[5];
let mut g = H[6];
let mut h = H[7];
for t in 0..80 {
let T1 = h + Sigma1(e) + Ch(e, f, g) + Wrapping(K[t]) + W[t % 16];
let T2 = Sigma0(a) + Maj(a, b, c);
h = g;
g = f;
f = e;
e = d + T1;
d = c;
c = b;
b = a;
a = T1 + T2;
if t % 16 == 15 {
for j in 0..16 {
W[j] += W[(j + 9) % 16] + sigma0(W[(j + 1) % 16]) + sigma1(W[(j + 14) % 16]);
}
}
}
H[0] += a;
H[1] += b;
H[2] += c;
H[3] += d;
H[4] += e;
H[5] += f;
H[6] += g;
H[7] += h;
}
for (d, h) in digest.chunks_mut(8).zip(H.iter()) {
d.copy_from_slice(&h.0.to_be_bytes());
}
unprocessed
}
#[rustfmt::skip]
static IV: [u8; 64] = [
0x6a,0x09,0xe6,0x67,0xf3,0xbc,0xc9,0x08,
0xbb,0x67,0xae,0x85,0x84,0xca,0xa7,0x3b,
0x3c,0x6e,0xf3,0x72,0xfe,0x94,0xf8,0x2b,
0xa5,0x4f,0xf5,0x3a,0x5f,0x1d,0x36,0xf1,
0x51,0x0e,0x52,0x7f,0xad,0xe6,0x82,0xd1,
0x9b,0x05,0x68,0x8c,0x2b,0x3e,0x6c,0x1f,
0x1f,0x83,0xd9,0xab,0xfb,0x41,0xbd,0x6b,
0x5b,0xe0,0xcd,0x19,0x13,0x7e,0x21,0x79,
];
#[allow(dead_code)]
pub fn sha512(digest: &mut [u8; 64], msg: &[u8]) {
let l = msg.len();
digest.copy_from_slice(&IV);
let unprocessed = hash_blocks(digest, msg);
let mut padding: [u8; 256] = [0u8; 256];
let padding_length = match unprocessed < 112 {
true => 128,
false => 256,
};
padding[..unprocessed].copy_from_slice(&msg[l - unprocessed..]);
padding[unprocessed] = 128;
#[cfg(target_pointer_width = "64")]
{
padding[padding_length - 9] = (l >> 61) as u8;
}
padding[padding_length - 8..].copy_from_slice(&((l << 3) as u64).to_be_bytes());
let padding = &padding[..padding_length];
hash_blocks(digest, padding);
}
pub struct Sha512 {
digest: Digest,
buffer: [u8; 128],
unprocessed: usize,
data_length: usize,
}
impl Default for Sha512 {
fn default() -> Self {
Self::new()
}
}
impl Sha512 {
pub fn new() -> Sha512 {
let mut digest: Digest = [0; SHA512_LENGTH];
digest.copy_from_slice(&IV);
Sha512 {
digest,
buffer: [0; 128],
unprocessed: 0,
data_length: 0,
}
}
pub fn update(&mut self, data: &[u8]) {
self.data_length += data.len();
if (self.unprocessed + data.len()) & !(0x80 - 1) == 0 {
self.buffer[self.unprocessed..self.unprocessed + data.len()].copy_from_slice(data);
self.unprocessed += data.len();
} else {
let filler = 128 - self.unprocessed;
self.buffer[self.unprocessed..].copy_from_slice(&data[..filler]);
hash_blocks(&mut self.digest, &self.buffer);
self.unprocessed = hash_blocks(&mut self.digest, &data[filler..]);
self.buffer[..self.unprocessed].copy_from_slice(&data[data.len() - self.unprocessed..]);
}
}
pub fn updated(mut self, data: &[u8]) -> Self {
self.update(data);
self
}
pub fn finalize(mut self) -> Digest {
let mut padding: [u8; 256] = [0u8; 256];
let padding_length = match self.unprocessed < 112 {
true => 128,
false => 256,
};
padding[..self.unprocessed].copy_from_slice(&self.buffer[..self.unprocessed]);
padding[self.unprocessed] = 128;
#[cfg(target_pointer_width = "64")]
{
padding[padding_length - 9] = (self.data_length >> 61) as u8;
}
padding[padding_length - 8..padding_length]
.copy_from_slice(&((self.data_length << 3) as u64).to_be_bytes());
let padding = &padding[..padding_length];
hash_blocks(&mut self.digest, padding);
self.digest
}
}