NULL_HDRLEN
if (caplen < NULL_HDRLEN) {
length -= NULL_HDRLEN;
null_print(p, (struct ip *)(p + NULL_HDRLEN), length);
ip_print(p + NULL_HDRLEN, length);
ip6_print(p + NULL_HDRLEN, length);
mpls_print(p + NULL_HDRLEN, length);
if (caplen < sizeof(struct ether_header) + NULL_HDRLEN) {
ep = (struct ether_header *)(p + NULL_HDRLEN);
p += NULL_HDRLEN + sizeof(struct ether_header);
default_print(p, caplen - NULL_HDRLEN);
default_print(p, caplen - NULL_HDRLEN);
default_print((const u_char *)(packetp + NULL_HDRLEN),
caplen - NULL_HDRLEN);
ether_print(p + NULL_HDRLEN, length);