blake2s_init_key
void blake2s_init_key(struct blake2s_state *state, const size_t outlen,
blake2s_init_key(&state, outlen, key, keylen);
blake2s_init_key(&state, COOKIE_MAC_SIZE, key, COOKIE_KEY_SIZE);
blake2s_init_key(&state, COOKIE_MAC_SIZE, key, COOKIE_COOKIE_SIZE);
blake2s_init_key(&state, COOKIE_COOKIE_SIZE, cc->cc_secret,