nsec3_find_cover
if(nsec3_find_cover(query->zone, hash, sizeof(hash), &cover))
exact = nsec3_find_cover(zone, domain->nsec3->hash_wc->hash.hash,
(void)nsec3_find_cover(zone, domain->nsec3->hash_wc->wc.hash,
exact = nsec3_find_cover(zone, domain->nsec3->ds_parent_hash->hash,
int nsec3_find_cover(struct zone* zone, uint8_t* hash, size_t hashlen,