Initial import from FreeBSD RELENG_4:
[dragonfly.git] / sys / net / if_loop.c
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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 * @(#)if_loop.c 8.1 (Berkeley) 6/10/93
34 * $FreeBSD: src/sys/net/if_loop.c,v 1.47.2.8 2003/06/01 01:46:11 silby Exp $
35 */
36
37/*
38 * Loopback interface driver for protocol testing and timing.
39 */
40#include "loop.h"
41
42#include "opt_atalk.h"
43#include "opt_inet.h"
44#include "opt_inet6.h"
45#include "opt_ipx.h"
46
47#include <sys/param.h>
48#include <sys/systm.h>
49#include <sys/kernel.h>
50#include <sys/mbuf.h>
51#include <sys/socket.h>
52#include <sys/sockio.h>
53
54#include <net/if.h>
55#include <net/if_types.h>
56#include <net/netisr.h>
57#include <net/route.h>
58#include <net/bpf.h>
59#include <net/bpfdesc.h>
60
61#ifdef INET
62#include <netinet/in.h>
63#include <netinet/in_var.h>
64#endif
65
66#ifdef IPX
67#include <netipx/ipx.h>
68#include <netipx/ipx_if.h>
69#endif
70
71#ifdef INET6
72#ifndef INET
73#include <netinet/in.h>
74#endif
75#include <netinet6/in6_var.h>
76#include <netinet/ip6.h>
77#endif
78
79#ifdef NS
80#include <netns/ns.h>
81#include <netns/ns_if.h>
82#endif
83
84#ifdef NETATALK
85#include <netatalk/at.h>
86#include <netatalk/at_var.h>
87#endif NETATALK
88
89int loioctl __P((struct ifnet *, u_long, caddr_t));
90static void lortrequest __P((int, struct rtentry *, struct rt_addrinfo *));
91
92static void loopattach __P((void *));
93PSEUDO_SET(loopattach, if_loop);
94
95int looutput __P((struct ifnet *ifp,
96 struct mbuf *m, struct sockaddr *dst, struct rtentry *rt));
97
98#ifdef TINY_LOMTU
99#define LOMTU (1024+512)
100#elif defined(LARGE_LOMTU)
101#define LOMTU 131072
102#else
103#define LOMTU 16384
104#endif
105
106struct ifnet loif[NLOOP];
107
108/* ARGSUSED */
109static void
110loopattach(dummy)
111 void *dummy;
112{
113 register struct ifnet *ifp;
114 register int i = 0;
115
116 for (ifp = loif; i < NLOOP; ifp++) {
117 ifp->if_name = "lo";
118 ifp->if_unit = i++;
119 ifp->if_mtu = LOMTU;
120 ifp->if_flags = IFF_LOOPBACK | IFF_MULTICAST;
121 ifp->if_ioctl = loioctl;
122 ifp->if_output = looutput;
123 ifp->if_type = IFT_LOOP;
124 ifp->if_snd.ifq_maxlen = ifqmaxlen;
125 if_attach(ifp);
126 bpfattach(ifp, DLT_NULL, sizeof(u_int));
127 }
128}
129
130int
131looutput(ifp, m, dst, rt)
132 struct ifnet *ifp;
133 register struct mbuf *m;
134 struct sockaddr *dst;
135 register struct rtentry *rt;
136{
137 struct mbuf *n;
138
139 if ((m->m_flags & M_PKTHDR) == 0)
140 panic("looutput no HDR");
141
142 if (rt && rt->rt_flags & (RTF_REJECT|RTF_BLACKHOLE)) {
143 m_freem(m);
144 return (rt->rt_flags & RTF_BLACKHOLE ? 0 :
145 rt->rt_flags & RTF_HOST ? EHOSTUNREACH : ENETUNREACH);
146 }
147 /*
148 * KAME requires that the packet to be contiguous on the
149 * mbuf. We need to make that sure.
150 * this kind of code should be avoided.
151 *
152 * XXX: KAME may no longer need contiguous packets. Once
153 * that has been verified, the following code _should_ be
154 * removed.
155 */
156 if (m && m->m_next != NULL) {
157
158 n = m_defrag(m, M_DONTWAIT);
159
160 if (n == NULL) {
161 m_freem(m);
162 return (ENOBUFS);
163 } else {
164 m = n;
165 }
166 }
167
168 ifp->if_opackets++;
169 ifp->if_obytes += m->m_pkthdr.len;
170#if 1 /* XXX */
171 switch (dst->sa_family) {
172 case AF_INET:
173 case AF_INET6:
174 case AF_IPX:
175 case AF_NS:
176 case AF_APPLETALK:
177 break;
178 default:
179 printf("looutput: af=%d unexpected\n", dst->sa_family);
180 m_freem(m);
181 return (EAFNOSUPPORT);
182 }
183#endif
184 return(if_simloop(ifp, m, dst->sa_family, 0));
185}
186
187/*
188 * if_simloop()
189 *
190 * This function is to support software emulation of hardware loopback,
191 * i.e., for interfaces with the IFF_SIMPLEX attribute. Since they can't
192 * hear their own broadcasts, we create a copy of the packet that we
193 * would normally receive via a hardware loopback.
194 *
195 * This function expects the packet to include the media header of length hlen.
196 */
197
198int
199if_simloop(ifp, m, af, hlen)
200 struct ifnet *ifp;
201 struct mbuf *m;
202 int af;
203 int hlen;
204{
205 int s, isr;
206 register struct ifqueue *ifq = 0;
207
208 KASSERT((m->m_flags & M_PKTHDR) != 0, ("if_simloop: no HDR"));
209 m->m_pkthdr.rcvif = ifp;
210
211 /* BPF write needs to be handled specially */
212 if (af == AF_UNSPEC) {
213 KASSERT(m->m_len >= sizeof(int), ("if_simloop: m_len"));
214 af = *(mtod(m, int *));
215 m->m_len -= sizeof(int);
216 m->m_pkthdr.len -= sizeof(int);
217 m->m_data += sizeof(int);
218 }
219
220 /* Let BPF see incoming packet */
221 if (ifp->if_bpf) {
222 struct mbuf m0, *n = m;
223
224 if (ifp->if_bpf->bif_dlt == DLT_NULL) {
225 /*
226 * We need to prepend the address family as
227 * a four byte field. Cons up a dummy header
228 * to pacify bpf. This is safe because bpf
229 * will only read from the mbuf (i.e., it won't
230 * try to free it or keep a pointer a to it).
231 */
232 m0.m_next = m;
233 m0.m_len = 4;
234 m0.m_data = (char *)&af;
235 n = &m0;
236 }
237 bpf_mtap(ifp, n);
238 }
239
240 /* Strip away media header */
241 if (hlen > 0) {
242 m_adj(m, hlen);
243#ifdef __alpha__
244 /* The alpha doesn't like unaligned data.
245 * We move data down in the first mbuf */
246 if (mtod(m, vm_offset_t) & 3) {
247 KASSERT(hlen >= 3, ("if_simloop: hlen too small"));
248 bcopy(m->m_data,
249 (char *)(mtod(m, vm_offset_t)
250 - (mtod(m, vm_offset_t) & 3)),
251 m->m_len);
252 mtod(m,vm_offset_t) -= (mtod(m, vm_offset_t) & 3);
253 }
254#endif
255 }
256
257 /* Deliver to upper layer protocol */
258 switch (af) {
259#ifdef INET
260 case AF_INET:
261 ifq = &ipintrq;
262 isr = NETISR_IP;
263 break;
264#endif
265#ifdef INET6
266 case AF_INET6:
267 m->m_flags |= M_LOOP;
268 ifq = &ip6intrq;
269 isr = NETISR_IPV6;
270 break;
271#endif
272#ifdef IPX
273 case AF_IPX:
274 ifq = &ipxintrq;
275 isr = NETISR_IPX;
276 break;
277#endif
278#ifdef NS
279 case AF_NS:
280 ifq = &nsintrq;
281 isr = NETISR_NS;
282 break;
283#endif
284#ifdef NETATALK
285 case AF_APPLETALK:
286 ifq = &atintrq2;
287 isr = NETISR_ATALK;
288 break;
289#endif NETATALK
290 default:
291 printf("if_simloop: can't handle af=%d\n", af);
292 m_freem(m);
293 return (EAFNOSUPPORT);
294 }
295 s = splimp();
296 if (IF_QFULL(ifq)) {
297 IF_DROP(ifq);
298 m_freem(m);
299 splx(s);
300 return (ENOBUFS);
301 }
302 IF_ENQUEUE(ifq, m);
303 schednetisr(isr);
304 ifp->if_ipackets++;
305 ifp->if_ibytes += m->m_pkthdr.len;
306 splx(s);
307 return (0);
308}
309
310/* ARGSUSED */
311static void
312lortrequest(cmd, rt, info)
313 int cmd;
314 struct rtentry *rt;
315 struct rt_addrinfo *info;
316{
317 if (rt) {
318 rt->rt_rmx.rmx_mtu = rt->rt_ifp->if_mtu; /* for ISO */
319 /*
320 * For optimal performance, the send and receive buffers
321 * should be at least twice the MTU plus a little more for
322 * overhead.
323 */
324 rt->rt_rmx.rmx_recvpipe =
325 rt->rt_rmx.rmx_sendpipe = 3 * LOMTU;
326 }
327}
328
329/*
330 * Process an ioctl request.
331 */
332/* ARGSUSED */
333int
334loioctl(ifp, cmd, data)
335 register struct ifnet *ifp;
336 u_long cmd;
337 caddr_t data;
338{
339 register struct ifaddr *ifa;
340 register struct ifreq *ifr = (struct ifreq *)data;
341 register int error = 0;
342
343 switch (cmd) {
344
345 case SIOCSIFADDR:
346 ifp->if_flags |= IFF_UP | IFF_RUNNING;
347 ifa = (struct ifaddr *)data;
348 ifa->ifa_rtrequest = lortrequest;
349 /*
350 * Everything else is done at a higher level.
351 */
352 break;
353
354 case SIOCADDMULTI:
355 case SIOCDELMULTI:
356 if (ifr == 0) {
357 error = EAFNOSUPPORT; /* XXX */
358 break;
359 }
360 switch (ifr->ifr_addr.sa_family) {
361
362#ifdef INET
363 case AF_INET:
364 break;
365#endif
366#ifdef INET6
367 case AF_INET6:
368 break;
369#endif
370
371 default:
372 error = EAFNOSUPPORT;
373 break;
374 }
375 break;
376
377 case SIOCSIFMTU:
378 ifp->if_mtu = ifr->ifr_mtu;
379 break;
380
381 case SIOCSIFFLAGS:
382 break;
383
384 default:
385 error = EINVAL;
386 }
387 return (error);
388}