get_option_uint32
if (get_option_uint32(&lease->leasetime, dhcp, DHO_LEASETIME) == 0) {
if (get_option_uint32(&lease->renewaltime, dhcp, DHO_RENEWALTIME) != 0)
if (get_option_uint32(&lease->rebindtime, dhcp, DHO_REBINDTIME) != 0)
int get_option_uint32(uint32_t *, const struct dhcp_message *, uint8_t);