checksum4_fold
iph->check = checksum4_fold((void *)iph, iph->ihl << 1, 0);
packet.icmph.checksum = checksum4_fold((void *)&packet.icmph,
iph->check = checksum4_fold((void *)iph, iph->ihl << 1, 0);
packet.icmph.checksum = checksum4_fold((void *)&packet.icmph,