1/* A sample version of rip_output() from /sys/netinet/raw_ip.c */
2
3rip_output(m, so)
4	register struct mbuf *m;
5	struct socket *so;
6{
7	register struct ip *ip;
8	int error;
9	struct rawcb *rp = sotorawcb(so);
10	struct sockaddr_in *sin;
11#if BSD>=43
12	short proto = rp->rcb_proto.sp_protocol;
13#else
14	short proto = so->so_proto->pr_protocol;
15#endif
16	/*
17	 * if the protocol is IPPROTO_RAW, the user handed us a
18	 * complete IP packet.  Otherwise, allocate an mbuf for a
19	 * header and fill it in as needed.
20	 */
21	if (proto != IPPROTO_RAW) {
22		/*
23		 * Calculate data length and get an mbuf
24		 * for IP header.
25		 */
26		int len = 0;
27		struct mbuf *m0;
28
29		for (m0 = m; m; m = m->m_next)
30			len += m->m_len;
31
32		m = m_get(M_DONTWAIT, MT_HEADER);
33		if (m == 0) {
34			m = m0;
35			error = ENOBUFS;
36			goto bad;
37		}
38		m->m_off = MMAXOFF - sizeof(struct ip);
39		m->m_len = sizeof(struct ip);
40		m->m_next = m0;
41
42		ip = mtod(m, struct ip *);
43		ip->ip_tos = 0;
44		ip->ip_off = 0;
45		ip->ip_p = proto;
46		ip->ip_len = sizeof(struct ip) + len;
47		ip->ip_ttl = MAXTTL;
48	} else
49		ip = mtod(m, struct ip *);
50
51	if (rp->rcb_flags & RAW_LADDR) {
52		sin = (struct sockaddr_in *)&rp->rcb_laddr;
53		if (sin->sin_family != AF_INET) {
54			error = EAFNOSUPPORT;
55			goto bad;
56		}
57		ip->ip_src.s_addr = sin->sin_addr.s_addr;
58	} else
59		ip->ip_src.s_addr = 0;
60
61	ip->ip_dst = ((struct sockaddr_in *)&rp->rcb_faddr)->sin_addr;
62
63#if BSD>=43
64	return (ip_output(m, rp->rcb_options, &rp->rcb_route,
65	   (so->so_options & SO_DONTROUTE) | IP_ALLOWBROADCAST));
66#else
67	return (ip_output(m, (struct mbuf *)0, &rp->rcb_route,
68	   (so->so_options & SO_DONTROUTE) | IP_ALLOWBROADCAST));
69#endif
70bad:
71	m_freem(m);
72	return (error);
73}
74