hash_final
void hash_final(struct iked_hash *, void *, size_t *);
hash_final(sa->sa_prf, psk, &psklen);
hash_final(prf, ibuf_data(skeyseed), &tmplen);
hash_final(prf, ibuf_data(t1), &hashlen);
hash_final(sa->sa_integr, ibuf_data(tmp), &tmplen);
hash_final(sa->sa_integr, ibuf_data(tmp), &tmplen);
hash_final(sa->sa_prf, ptr, &tmplen);