1 /* A sample version of rip_output() from /sys/netinet/raw_ip.c */
2
rip_output(m,so)3 rip_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
70 bad:
71 m_freem(m);
72 return (error);
73 }
74