DHCP_END
payload[0] = (uint8_t)~DHCP_END;
payload[1] = DHCP_END;
if (payload[used_bytes - 1] != DHCP_END) {
payload[used_bytes] = DHCP_END;
if ((uint8_t)data[used_bytes - 1] != DHCP_END) {
if (tag == DHCP_END) {