icmp6_cksum
icp6->icmp6_cksum = 0;
pd->pcksum = &pd->hdr.icmp6.icmp6_cksum;
#define mld_cksum mld_icmp6_hdr.icmp6_cksum
#define nd_rs_cksum nd_rs_hdr.icmp6_cksum
#define nd_ra_cksum nd_ra_hdr.icmp6_cksum
#define nd_ns_cksum nd_ns_hdr.icmp6_cksum
#define nd_na_cksum nd_na_hdr.icmp6_cksum
#define nd_rd_cksum nd_rd_hdr.icmp6_cksum
#define ni_cksum icmp6_ni_hdr.icmp6_cksum
#define rr_cksum rr_hdr.icmp6_cksum
u_int16_t icmp6_cksum; /* checksum field */
icmp6->icmp6_cksum = 0;
const int icmp6off = offsetof(struct icmp6_hdr, icmp6_cksum);
offset += offsetof(struct icmp6_hdr, icmp6_cksum);
offset += offsetof(struct icmp6_hdr, icmp6_cksum);
off = offsetof(struct icmp6_hdr, icmp6_cksum);
icp6->icmp6_cksum = 0;
icp6->icmp6_cksum = 0;
icp6->icmp6_cksum = in_cksum((u_short *)icp6,
sum = icmp6_cksum(ip, dp, length);
icmp6_sum = EXTRACT_16BITS(&dp->icmp6_cksum);
icp->icmp6_cksum = 0;