INNER CODE UNIT · Rust
pk_encode
orion-rs/orion · src/hazardous/dsa/ml_dsa/internal/mod.rs:199
fn pk_encode<const PK_ENCODED_SIZE: usize>(
rho: &[u8],
t1: &[RingElement],
) -> [u8; PK_ENCODED_SIZE] {
debug_assert_eq!(rho.len(), 32);
debug_assert_eq!(PK_ENCODED_SIZE, Self::PUBLIC_KEY_SIZE);
let mut pk = [0u8; PK_ENCODED_SIZE];
pk[..32].copy_from_slice(rho);
for (idx, encpoly) in (0..Self::DIM_K).zip(pk[32..].chunks_exact_mut(320)) {
for i in 0..256 / 4 {
let c = |k: usize| t1[idx].coefficients[4 * i + k].0;
encpoly[5 * i] = c(0) as u8;
encpoly[5 * i + 1] = ((c(0) >> 8) | (c(1) << 2)) as u8;
encpoly[5 * i + 2] = ((c(1) >> 6) | (c(2) << 4)) as u8;
encpoly[5 * i + 3] = ((c(2) >> 4) | (c(3) << 6)) as u8;
encpoly[5 * i + 4] = (c(3) >> 2) as u8;