1/*
2 * Copyright (c) 1982, 1986, 1993
3 * The Regents of the University of California. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 * must display the following acknowledgement:
15 * This product includes software developed by the University of
16 * California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 *
33 * From: @(#)if_loop.c 8.1 (Berkeley) 6/10/93
34 * $Id: if_disc.c,v 1.12 1996/04/07 17:39:03 bde Exp $
35 */
36
37/*
38 * Discard interface driver for protocol testing and timing.
39 * (Based on the loopback.)
40 */
41
42#include <sys/param.h>
43#include <sys/systm.h>
44#include <sys/kernel.h>
45#include <sys/mbuf.h>
46#include <sys/socket.h>
47#include <sys/errno.h>
48#include <sys/ioctl.h>
49#include <sys/time.h>
50
51#include <net/if.h>
52#include <net/if_types.h>
53#include <net/netisr.h>
54#include <net/route.h>
55#include <net/bpf.h>
56
57#ifdef INET
58#include <netinet/in.h>
59#include <netinet/in_systm.h>
60#include <netinet/in_var.h>
61#include <netinet/ip.h>
62#endif
63
64#ifdef NS
65#include <netns/ns.h>
66#include <netns/ns_if.h>
67#endif
68
69#ifdef ISO
70#include <netiso/iso.h>
71#include <netiso/iso_var.h>
72#endif
73
74#include "bpfilter.h"
75
76#ifdef TINY_DSMTU
77#define DSMTU (1024+512)
78#else
79#define DSMTU 65532
80#endif
81
82static void discattach __P((void *dummy));
83PSEUDO_SET(discattach, if_disc);
84
85static struct ifnet dsif;
86static int dsoutput(struct ifnet *, struct mbuf *, struct sockaddr *,
87 struct rtentry *);
88static void dsrtrequest(int cmd, struct rtentry *rt, struct sockaddr *sa);
89static int dsioctl(struct ifnet *, int, caddr_t);
90
91/* ARGSUSED */
92static void
93discattach(dummy)
94 void *dummy;
95{
96 register struct ifnet *ifp = &dsif;
97
98 ifp->if_name = "ds";
99 ifp->if_mtu = DSMTU;
100 ifp->if_flags = IFF_LOOPBACK | IFF_MULTICAST;
101 ifp->if_ioctl = dsioctl;
102 ifp->if_output = dsoutput;
103 ifp->if_type = IFT_LOOP;
104 ifp->if_hdrlen = 0;
105 ifp->if_addrlen = 0;
106 if_attach(ifp);
107#if NBPFILTER > 0
108 bpfattach(ifp, DLT_NULL, sizeof(u_int));
109#endif
110}
111
112static int
113dsoutput(ifp, m, dst, rt)
114 struct ifnet *ifp;
115 register struct mbuf *m;
116 struct sockaddr *dst;
117 register struct rtentry *rt;
118{
119 if ((m->m_flags & M_PKTHDR) == 0)
120 panic("dsoutput no HDR");
121#if NBPFILTER > 0
122 /* BPF write needs to be handled specially */
123 if (dst->sa_family == AF_UNSPEC) {
124 dst->sa_family = *(mtod(m, int *));
125 m->m_len -= sizeof(int);
126 m->m_pkthdr.len -= sizeof(int);
127 m->m_data += sizeof(int);
128 }
129
130 if (dsif.if_bpf) {
131 /*
132 * We need to prepend the address family as
133 * a four byte field. Cons up a dummy header
134 * to pacify bpf. This is safe because bpf
135 * will only read from the mbuf (i.e., it won't
136 * try to free it or keep a pointer a to it).
137 */
138 struct mbuf m0;
139 u_int af = dst->sa_family;
140
141 m0.m_next = m;
142 m0.m_len = 4;
143 m0.m_data = (char *)&af;
144
145 bpf_mtap(&dsif, &m0);
146 }
147#endif
148 m->m_pkthdr.rcvif = ifp;
149
150 if (rt && rt->rt_flags & (RTF_REJECT|RTF_BLACKHOLE)) {
151 m_freem(m);
152 return (rt->rt_flags & RTF_BLACKHOLE ? 0 :
153 rt->rt_flags & RTF_HOST ? EHOSTUNREACH : ENETUNREACH);
154 }
155 ifp->if_opackets++;
156 ifp->if_obytes += m->m_pkthdr.len;
157
158 m_freem(m);
159 return 0;
160}
161
162/* ARGSUSED */
163static void
164dsrtrequest(cmd, rt, sa)
165 int cmd;
166 struct rtentry *rt;
167 struct sockaddr *sa;
168{
169 if (rt)
170 rt->rt_rmx.rmx_mtu = DSMTU;
171}
172
173/*
174 * Process an ioctl request.
175 */
176/* ARGSUSED */
177static int
178dsioctl(ifp, cmd, data)
179 register struct ifnet *ifp;
180 int cmd;
181 caddr_t data;
182{
183 register struct ifaddr *ifa;
184 register struct ifreq *ifr = (struct ifreq *)data;
185 register int error = 0;
186
187 switch (cmd) {
188
189 case SIOCSIFADDR:
190 ifp->if_flags |= IFF_UP;
191 ifa = (struct ifaddr *)data;
192 if (ifa != 0)
193 ifa->ifa_rtrequest = dsrtrequest;
194 /*
195 * Everything else is done at a higher level.
196 */
197 break;
198
199 case SIOCADDMULTI:
200 case SIOCDELMULTI:
201 if (ifr == 0) {
202 error = EAFNOSUPPORT; /* XXX */
203 break;
204 }
205 switch (ifr->ifr_addr.sa_family) {
206
207#ifdef INET
208 case AF_INET:
209 break;
210#endif
211
212 default:
213 error = EAFNOSUPPORT;
214 break;
215 }
216 break;
217
218 case SIOCSIFMTU:
219 ifp->if_mtu = ifr->ifr_mtu;
220 break;
221
222 default:
223 error = EINVAL;
224 }
225 return (error);
226}