#![allow(dead_code)]
use base64::Engine as _;
pub const B64: base64::engine::GeneralPurpose = base64::engine::general_purpose::STANDARD;
pub struct GoldenFixture {
pub levels_option: u32,
pub positions: Vec<f32>,
pub indices: Vec<u32>,
pub levels: Vec<GoldenLevel>,
pub parents_by_level: Vec<Vec<i64>>,
}
pub struct GoldenLevel {
pub error: f64,
pub positions: Vec<f32>,
pub indices: Vec<u32>,
pub descriptors: Vec<u32>,
pub vertex_remap: Vec<u32>,
pub local_triangle_indices: Vec<u32>,
pub bounds: Vec<f32>,
pub source_triangles: Vec<u32>,
pub cluster_source_spans: Vec<u32>,
}
pub fn decode_u32(json: &serde_json::Value, key: &str) -> Vec<u32> {
let raw = B64.decode(json[key].as_str().expect("b64 string")).expect("b64");
raw.chunks_exact(4)
.map(|c| u32::from_le_bytes(c.try_into().expect("4 bytes")))
.collect()
}
pub fn decode_f32(json: &serde_json::Value, key: &str) -> Vec<f32> {
let raw = B64.decode(json[key].as_str().expect("b64 string")).expect("b64");
raw.chunks_exact(4)
.map(|c| f32::from_le_bytes(c.try_into().expect("4 bytes")))
.collect()
}
pub fn load_fixture(name: &str) -> GoldenFixture {
let path = format!("{}/tests/fixtures/{name}.golden.json", env!("CARGO_MANIFEST_DIR"));
let text = std::fs::read_to_string(&path)
.unwrap_or_else(|e| panic!("cannot read fixture {path}: {e}"));
let json: serde_json::Value = serde_json::from_str(&text).expect("json");
let options = &json["options"];
GoldenFixture {
levels_option: options["levels"].as_u64().expect("levels") as u32,
positions: decode_f32(&json["input"], "positionsB64"),
indices: decode_u32(&json["input"], "indicesB64"),
levels: json["levels"]
.as_array()
.expect("levels array")
.iter()
.map(|level| GoldenLevel {
error: level["error"].as_f64().expect("error"),
positions: decode_f32(level, "positionsB64"),
indices: decode_u32(level, "indicesB64"),
descriptors: decode_u32(level, "descriptorsB64"),
vertex_remap: decode_u32(level, "vertexRemapB64"),
local_triangle_indices: decode_u32(level, "localTriangleIndicesB64"),
bounds: decode_f32(level, "boundsB64"),
source_triangles: decode_u32(level, "sourceTrianglesB64"),
cluster_source_spans: decode_u32(level, "clusterSourceSpansB64"),
})
.collect(),
parents_by_level: json["parentsByLevel"]
.as_array()
.expect("parents")
.iter()
.map(|parents| {
parents
.as_array()
.expect("parent row")
.iter()
.map(|v| v.as_i64().expect("parent index"))
.collect()
})
.collect(),
}
}
pub fn sha256(data: &[u8]) -> [u8; 32] {
const K: [u32; 64] = [
0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5, 0x3956c25b, 0x59f111f1, 0x923f82a4,
0xab1c5ed5, 0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3, 0x72be5d74, 0x80deb1fe,
0x9bdc06a7, 0xc19bf174, 0xe49b69c1, 0xefbe4786, 0x0fc19dc6, 0x240ca1cc, 0x2de92c6f,
0x4a7484aa, 0x5cb0a9dc, 0x76f988da, 0x983e5152, 0xa831c66d, 0xb00327c8, 0xbf597fc7,
0xc6e00bf3, 0xd5a79147, 0x06ca6351, 0x14292967, 0x27b70a85, 0x2e1b2138, 0x4d2c6dfc,
0x53380d13, 0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85, 0xa2bfe8a1, 0xa81a664b,
0xc24b8b70, 0xc76c51a3, 0xd192e819, 0xd6990624, 0xf40e3585, 0x106aa070, 0x19a4c116,
0x1e376c08, 0x2748774c, 0x34b0bcb5, 0x391c0cb3, 0x4ed8aa4a, 0x5b9cca4f, 0x682e6ff3,
0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208, 0x90befffa, 0xa4506ceb, 0xbef9a3f7,
0xc67178f2,
];
let mut h: [u32; 8] = [
0x6a09e667, 0xbb67ae85, 0x3c6ef372, 0xa54ff53a, 0x510e527f, 0x9b05688c, 0x1f83d9ab,
0x5be0cd19,
];
let bit_len = (data.len() as u64).wrapping_mul(8);
let mut message = data.to_vec();
message.push(0x80);
while message.len() % 64 != 56 {
message.push(0);
}
message.extend_from_slice(&bit_len.to_be_bytes());
let mut w = [0u32; 64];
for block in message.chunks_exact(64) {
for (i, word) in w.iter_mut().take(16).enumerate() {
*word = u32::from_be_bytes(block[i * 4..i * 4 + 4].try_into().expect("4 bytes"));
}
for i in 16..64 {
let s0 = w[i - 15].rotate_right(7) ^ w[i - 15].rotate_right(18) ^ (w[i - 15] >> 3);
let s1 = w[i - 2].rotate_right(17) ^ w[i - 2].rotate_right(19) ^ (w[i - 2] >> 10);
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 hh) =
(h[0], h[1], h[2], h[3], h[4], h[5], h[6], h[7]);
for i in 0..64 {
let s1 = e.rotate_right(6) ^ e.rotate_right(11) ^ e.rotate_right(25);
let ch = (e & f) ^ ((!e) & g);
let temp1 = hh
.wrapping_add(s1)
.wrapping_add(ch)
.wrapping_add(K[i])
.wrapping_add(w[i]);
let s0 = a.rotate_right(2) ^ a.rotate_right(13) ^ a.rotate_right(22);
let maj = (a & b) ^ (a & c) ^ (b & c);
let temp2 = s0.wrapping_add(maj);
hh = g;
g = f;
f = e;
e = d.wrapping_add(temp1);
d = c;
c = b;
b = a;
a = temp1.wrapping_add(temp2);
}
h[0] = h[0].wrapping_add(a);
h[1] = h[1].wrapping_add(b);
h[2] = h[2].wrapping_add(c);
h[3] = h[3].wrapping_add(d);
h[4] = h[4].wrapping_add(e);
h[5] = h[5].wrapping_add(f);
h[6] = h[6].wrapping_add(g);
h[7] = h[7].wrapping_add(hh);
}
let mut out = [0u8; 32];
for (i, word) in h.iter().enumerate() {
out[i * 4..i * 4 + 4].copy_from_slice(&word.to_be_bytes());
}
out
}
pub fn sha256_hex(data: &[u8]) -> String {
sha256(data).iter().map(|b| format!("{b:02x}")).collect()
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn sha256_fips_vectors() {
assert_eq!(
sha256_hex(b""),
"e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855"
);
assert_eq!(
sha256_hex(b"abc"),
"ba7816bf8f01cfea414140de5dae2223b00361a396177a9cb410ff61f20015ad"
);
let long = b"abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq";
assert_eq!(
sha256_hex(long),
"248d6a61d20638b8e5c026930c3e6039a33ce45964ff2167f6ecedd419db06c1"
);
let million = vec![b'a'; 1_000_000];
assert_eq!(
sha256_hex(&million),
"cdc76e5c9914fb9281a1c7e284d73e67f1809a48a497200e046d39ccc7112cd0"
);
}
}