Function me_input

freebsd/net/if_me.c:466–532

}

static int
me_input(struct mbuf *m, int off, int proto, void *arg)
{
	struct me_softc *sc = arg;
	struct mobhdr *mh;
	struct ifnet *ifp;
	struct ip *ip;
	int hlen;

	NET_EPOCH_ASSERT();

	ifp = ME2IFP(sc);
	/* checks for short packets */
	hlen = sizeof(struct mobhdr);
	if (m->m_pkthdr.len < sizeof(struct ip) + hlen)
		hlen -= sizeof(struct in_addr);
	if (m->m_len < sizeof(struct ip) + hlen)
		m = m_pullup(m, sizeof(struct ip) + hlen);
	if (m == NULL)
		goto drop;
	mh = (struct mobhdr *)mtodo(m, sizeof(struct ip));
	/* check for wrong flags */
	if (mh->mob_flags & (~MOB_FLAGS_SP)) {
		m_freem(m);
		goto drop;
	}
	if (mh->mob_flags) {
	       if (hlen != sizeof(struct mobhdr)) {
			m_freem(m);
			goto drop;
	       }
	} else
		hlen = sizeof(struct mobhdr) - sizeof(struct in_addr);
	/* check mobile header checksum */
	if (me_in_cksum((uint16_t *)mh, hlen / sizeof(uint16_t)) != 0) {
		m_freem(m);
		goto drop;
	}
#ifdef MAC
	mac_ifnet_create_mbuf(ifp, m);
#endif
	ip = mtod(m, struct ip *);
	ip->ip_dst = mh->mob_dst;
	ip->ip_p = mh->mob_proto;
	ip->ip_sum = 0;
	ip->ip_len = htons(m->m_pkthdr.len - hlen);
	if (mh->mob_flags)
		ip->ip_src = mh->mob_src;
	memmove(mtodo(m, hlen), ip, sizeof(struct ip));
	m_adj(m, hlen);
	m_clrprotoflags(m);
	m->m_pkthdr.rcvif = ifp;
	m->m_pkthdr.csum_flags |= (CSUM_IP_CHECKED | CSUM_IP_VALID);
	M_SETFIB(m, ifp->if_fib);
	hlen = AF_INET;
	BPF_MTAP2(ifp, &hlen, sizeof(hlen), m);
	if_inc_counter(ifp, IFCOUNTER_IPACKETS, 1);
	if_inc_counter(ifp, IFCOUNTER_IBYTES, m->m_pkthdr.len);