Function hkdf_sha256

src/pq.rs:57–75

(salt: &[u8], ikm: &[u8], info: &[u8], out: &mut [u8])

}

pub fn hkdf_sha256(salt: &[u8], ikm: &[u8], info: &[u8], out: &mut [u8]) {
    let mut prk = [0u8; crypto_kdf_hkdf_sha256_KEYBYTES as usize];
    unsafe {
        crypto_kdf_hkdf_sha256_extract(
            prk.as_mut_ptr(),
            salt.as_ptr(),
            salt.len() as _,
            ikm.as_ptr(),
            ikm.len() as _,
        );
        crypto_kdf_hkdf_sha256_expand(
            out.as_mut_ptr(),
            out.len() as _,
            info.as_ptr() as *const c_char,
            info.len() as _,
            prk.as_ptr(),
        );
    }
}

/// An X-Wing key pair, stored as its 32-byte secret seed. The decapsulation
/// key is derived from the seed on demand.