xref: /openbsd-src/sys/net/if_gif.c (revision b2ea75c1b17e1a9a339660e7ed45cd24946b230e)
1 /*	$OpenBSD: if_gif.c,v 1.20 2001/07/27 15:48:38 itojun Exp $	*/
2 /*	$KAME: if_gif.c,v 1.43 2001/02/20 08:51:07 itojun Exp $	*/
3 
4 /*
5  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. Neither the name of the project nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 #include <sys/param.h>
34 #include <sys/systm.h>
35 #include <sys/kernel.h>
36 #include <sys/mbuf.h>
37 #include <sys/socket.h>
38 #include <sys/sockio.h>
39 #include <sys/syslog.h>
40 
41 #include <net/if.h>
42 #include <net/if_types.h>
43 #include <net/route.h>
44 #include <net/bpf.h>
45 
46 #ifdef	INET
47 #include <netinet/in.h>
48 #include <netinet/in_var.h>
49 #include <netinet/in_gif.h>
50 #endif	/* INET */
51 
52 #ifdef INET6
53 #ifndef INET
54 #include <netinet/in.h>
55 #endif
56 #include <netinet6/in6_gif.h>
57 #endif /* INET6 */
58 
59 #include <net/if_gif.h>
60 
61 #include "bpfilter.h"
62 #include "bridge.h"
63 
64 extern int ifqmaxlen;
65 
66 int ngif;
67 void gifattach __P((int));
68 
69 /*
70  * gif global variable definitions
71  */
72 struct gif_softc *gif_softc = 0;
73 
74 void
75 gifattach(n)
76 	int n;
77 {
78 	register struct gif_softc *sc;
79 	register int i;
80 
81 	ngif = n;
82 	gif_softc = sc = malloc (ngif * sizeof(struct gif_softc),
83 	    M_DEVBUF, M_WAIT);
84 	bzero(sc, ngif * sizeof(struct gif_softc));
85 	for (i = 0; i < ngif; sc++, i++) {
86 		sprintf(sc->gif_if.if_xname, "gif%d", i);
87 		sc->gif_if.if_mtu    = GIF_MTU;
88 		sc->gif_if.if_flags  = IFF_POINTOPOINT | IFF_MULTICAST;
89 		sc->gif_if.if_ioctl  = gif_ioctl;
90 		sc->gif_if.if_start = gif_start;
91 		sc->gif_if.if_output = gif_output;
92 		sc->gif_if.if_type   = IFT_GIF;
93 		sc->gif_if.if_snd.ifq_maxlen = ifqmaxlen;
94 		sc->gif_if.if_softc = sc;
95 		if_attach(&sc->gif_if);
96 
97 #if NBPFILTER > 0
98 		bpfattach(&sc->gif_if.if_bpf, &sc->gif_if, DLT_NULL,
99 			  sizeof(u_int));
100 #endif
101 	}
102 }
103 
104 void
105 gif_start(ifp)
106         struct ifnet *ifp;
107 {
108 #if NBRIDGE > 0
109         struct sockaddr dst;
110 #endif /* NBRIDGE */
111 
112         struct mbuf *m;
113 	int s;
114 
115 #if NBRIDGE > 0
116 	bzero(&dst, sizeof(dst));
117 
118 	/*
119 	 * XXX The assumption here is that only the ethernet bridge
120 	 * uses the start routine of this interface, and it's thus
121 	 * safe to do this.
122 	 */
123 	dst.sa_family = AF_LINK;
124 #endif /* NBRIDGE */
125 
126 	for (;;) {
127 	        s = splimp();
128 		IF_DEQUEUE(&ifp->if_snd, m);
129 		splx(s);
130 
131 		if (m == NULL) return;
132 
133 #if NBRIDGE > 0
134 		/* Sanity check -- interface should be member of a bridge */
135 		if (ifp->if_bridge == NULL) m_freem(m);
136 		else gif_output(ifp, m, &dst, NULL);
137 #else
138 		m_freem(m);
139 #endif /* NBRIDGE */
140 	}
141 }
142 
143 int
144 gif_output(ifp, m, dst, rt)
145 	struct ifnet *ifp;
146 	struct mbuf *m;
147 	struct sockaddr *dst;
148 	struct rtentry *rt;	/* added in net2 */
149 {
150 	register struct gif_softc *sc = (struct gif_softc*)ifp;
151 	int error = 0;
152 	struct m_tag *mtag;
153 
154 	/*
155 	 * gif may cause infinite recursion calls when misconfigured.
156 	 * We'll prevent this by detecting loops.
157 	 */
158 	for (mtag = m_tag_find(m, PACKET_TAG_GIF, NULL); mtag;
159 	     mtag = m_tag_find(m, PACKET_TAG_GIF, mtag)) {
160 		if (!bcmp((caddr_t)(mtag + 1), &ifp, sizeof(struct ifnet *))) {
161 			IF_DROP(&ifp->if_snd);
162 			log(LOG_NOTICE,
163 			    "gif_output: recursively called too many times\n");
164 			m_freem(m);
165 			error = EIO;	/* is there better errno? */
166 			goto end;
167 		}
168 	}
169 
170 	mtag = m_tag_get(PACKET_TAG_GIF, sizeof(struct ifnet *), M_NOWAIT);
171 	if (mtag == NULL) {
172 		IF_DROP(&ifp->if_snd);
173 		m_freem(m);
174 		error = ENOMEM;
175 		goto end;
176 	}
177 	bcopy(&ifp, (caddr_t)(mtag + 1), sizeof(struct ifnet *));
178 	m_tag_prepend(m, mtag);
179 
180 	m->m_flags &= ~(M_BCAST|M_MCAST);
181 	if (!(ifp->if_flags & IFF_UP) ||
182 	    sc->gif_psrc == NULL || sc->gif_pdst == NULL) {
183 		log(LOG_NOTICE,
184 		    "gif_output: attempt to use unconfigured interface %s\n",
185 		    ifp->if_xname);
186 		m_freem(m);
187 		error = ENETDOWN;
188 		goto end;
189 	}
190 
191 #if NBPFILTER > 0
192 	if (ifp->if_bpf) {
193 		/*
194 		 * We need to prepend the address family as
195 		 * a four byte field.  Cons up a dummy header
196 		 * to pacify bpf.  This is safe because bpf
197 		 * will only read from the mbuf (i.e., it won't
198 		 * try to free it or keep a pointer a to it).
199 		 */
200 		struct mbuf m0;
201 		u_int32_t af = dst->sa_family;
202 
203 		m0.m_next = m;
204 		m0.m_len = 4;
205 		m0.m_data = (char *)&af;
206 
207 		bpf_mtap(ifp->if_bpf, &m0);
208 	}
209 #endif
210 	ifp->if_opackets++;
211 	ifp->if_obytes += m->m_pkthdr.len;
212 
213 	switch (sc->gif_psrc->sa_family) {
214 #ifdef INET
215 	case AF_INET:
216 		error = in_gif_output(ifp, dst->sa_family, m, rt);
217 		break;
218 #endif
219 #ifdef INET6
220 	case AF_INET6:
221 		error = in6_gif_output(ifp, dst->sa_family, m, rt);
222 		break;
223 #endif
224 	default:
225 		m_freem(m);
226 		error = ENETDOWN;
227 	}
228 
229   end:
230 	if (error) ifp->if_oerrors++;
231 	return error;
232 }
233 
234 int
235 gif_ioctl(ifp, cmd, data)
236 	struct ifnet *ifp;
237 	u_long cmd;
238 	caddr_t data;
239 {
240 	struct gif_softc *sc  = (struct gif_softc*)ifp;
241 	struct ifreq     *ifr = (struct ifreq*)data;
242 	int error = 0, size;
243 	struct sockaddr *dst, *src;
244 	struct sockaddr *sa;
245 	int i;
246 	int s;
247 	struct gif_softc *sc2;
248 
249 	switch (cmd) {
250 	case SIOCSIFADDR:
251 		break;
252 
253 	case SIOCSIFDSTADDR:
254 		break;
255 
256 	case SIOCADDMULTI:
257 	case SIOCDELMULTI:
258 		switch (ifr->ifr_addr.sa_family) {
259 #ifdef INET
260 		case AF_INET:	/* IP supports Multicast */
261 			break;
262 #endif /* INET */
263 #ifdef INET6
264 		case AF_INET6:	/* IP6 supports Multicast */
265 			break;
266 #endif /* INET6 */
267 		default:  /* Other protocols doesn't support Multicast */
268 			error = EAFNOSUPPORT;
269 			break;
270 		}
271 		break;
272 
273 	case SIOCSIFPHYADDR:
274 #ifdef INET6
275 	case SIOCSIFPHYADDR_IN6:
276 #endif /* INET6 */
277 	case SIOCSLIFPHYADDR:
278 		switch (cmd) {
279 #ifdef INET
280 		case SIOCSIFPHYADDR:
281 			src = (struct sockaddr *)
282 				&(((struct in_aliasreq *)data)->ifra_addr);
283 			dst = (struct sockaddr *)
284 				&(((struct in_aliasreq *)data)->ifra_dstaddr);
285 			break;
286 #endif
287 #ifdef INET6
288 		case SIOCSIFPHYADDR_IN6:
289 			src = (struct sockaddr *)
290 				&(((struct in6_aliasreq *)data)->ifra_addr);
291 			dst = (struct sockaddr *)
292 				&(((struct in6_aliasreq *)data)->ifra_dstaddr);
293 			break;
294 #endif
295 		case SIOCSLIFPHYADDR:
296 			src = (struct sockaddr *)
297 				&(((struct if_laddrreq *)data)->addr);
298 			dst = (struct sockaddr *)
299 				&(((struct if_laddrreq *)data)->dstaddr);
300 		}
301 
302 		/* sa_family must be equal */
303 		if (src->sa_family != dst->sa_family)
304 			return EINVAL;
305 
306 		/* validate sa_len */
307 		switch (src->sa_family) {
308 #ifdef INET
309 		case AF_INET:
310 			if (src->sa_len != sizeof(struct sockaddr_in))
311 				return EINVAL;
312 			break;
313 #endif
314 #ifdef INET6
315 		case AF_INET6:
316 			if (src->sa_len != sizeof(struct sockaddr_in6))
317 				return EINVAL;
318 			break;
319 #endif
320 		default:
321 			return EAFNOSUPPORT;
322 		}
323 		switch (dst->sa_family) {
324 #ifdef INET
325 		case AF_INET:
326 			if (dst->sa_len != sizeof(struct sockaddr_in))
327 				return EINVAL;
328 			break;
329 #endif
330 #ifdef INET6
331 		case AF_INET6:
332 			if (dst->sa_len != sizeof(struct sockaddr_in6))
333 				return EINVAL;
334 			break;
335 #endif
336 		default:
337 			return EAFNOSUPPORT;
338 		}
339 
340 		/* check sa_family looks sane for the cmd */
341 		switch (cmd) {
342 		case SIOCSIFPHYADDR:
343 			if (src->sa_family == AF_INET)
344 				break;
345 			return EAFNOSUPPORT;
346 #ifdef INET6
347 		case SIOCSIFPHYADDR_IN6:
348 			if (src->sa_family == AF_INET6)
349 				break;
350 			return EAFNOSUPPORT;
351 #endif /* INET6 */
352 		case SIOCSLIFPHYADDR:
353 			/* checks done in the above */
354 			break;
355 		}
356 
357 		for (i = 0; i < ngif; i++) {
358 			sc2 = gif_softc + i;
359 			if (sc2 == sc)
360 				continue;
361 			if (!sc2->gif_pdst || !sc2->gif_psrc)
362 				continue;
363 			if (sc2->gif_pdst->sa_family != dst->sa_family ||
364 			    sc2->gif_pdst->sa_len != dst->sa_len ||
365 			    sc2->gif_psrc->sa_family != src->sa_family ||
366 			    sc2->gif_psrc->sa_len != src->sa_len)
367 				continue;
368 			/* can't configure same pair of address onto two gifs */
369 			if (bcmp(sc2->gif_pdst, dst, dst->sa_len) == 0 &&
370 			    bcmp(sc2->gif_psrc, src, src->sa_len) == 0) {
371 				error = EADDRNOTAVAIL;
372 				goto bad;
373 			}
374 
375 			/* can't configure multiple multi-dest interfaces */
376 #define multidest(x) \
377 	(((struct sockaddr_in *)(x))->sin_addr.s_addr == INADDR_ANY)
378 #ifdef INET6
379 #define multidest6(x) \
380 	(IN6_IS_ADDR_UNSPECIFIED(&((struct sockaddr_in6 *)(x))->sin6_addr))
381 #endif
382 			if (dst->sa_family == AF_INET &&
383 			    multidest(dst) && multidest(sc2->gif_pdst)) {
384 				error = EADDRNOTAVAIL;
385 				goto bad;
386 			}
387 #ifdef INET6
388 			if (dst->sa_family == AF_INET6 &&
389 			    multidest6(dst) && multidest6(sc2->gif_pdst)) {
390 				error = EADDRNOTAVAIL;
391 				goto bad;
392 			}
393 #endif
394 		}
395 
396 		if (sc->gif_psrc)
397 			free((caddr_t)sc->gif_psrc, M_IFADDR);
398 		sa = (struct sockaddr *)malloc(src->sa_len, M_IFADDR, M_WAITOK);
399 		bcopy((caddr_t)src, (caddr_t)sa, src->sa_len);
400 		sc->gif_psrc = sa;
401 
402 		if (sc->gif_pdst)
403 			free((caddr_t)sc->gif_pdst, M_IFADDR);
404 		sa = (struct sockaddr *)malloc(dst->sa_len, M_IFADDR, M_WAITOK);
405 		bcopy((caddr_t)dst, (caddr_t)sa, dst->sa_len);
406 		sc->gif_pdst = sa;
407 
408 		s = splnet();
409 		ifp->if_flags |= IFF_RUNNING;
410 		if_up(ifp);		/* send up RTM_IFINFO */
411 		splx(s);
412 
413 		error = 0;
414 		break;
415 
416 #ifdef SIOCDIFPHYADDR
417 	case SIOCDIFPHYADDR:
418 		if (sc->gif_psrc) {
419 			free((caddr_t)sc->gif_psrc, M_IFADDR);
420 			sc->gif_psrc = NULL;
421 		}
422 		if (sc->gif_pdst) {
423 			free((caddr_t)sc->gif_pdst, M_IFADDR);
424 			sc->gif_pdst = NULL;
425 		}
426 		/* change the IFF_{UP, RUNNING} flag as well? */
427 		break;
428 #endif
429 
430 	case SIOCGIFPSRCADDR:
431 #ifdef INET6
432 	case SIOCGIFPSRCADDR_IN6:
433 #endif /* INET6 */
434 		if (sc->gif_psrc == NULL) {
435 			error = EADDRNOTAVAIL;
436 			goto bad;
437 		}
438 		src = sc->gif_psrc;
439 		switch (cmd) {
440 #ifdef INET
441 		case SIOCGIFPSRCADDR:
442 			dst = &ifr->ifr_addr;
443 			size = sizeof(ifr->ifr_addr);
444 			break;
445 #endif /* INET */
446 #ifdef INET6
447 		case SIOCGIFPSRCADDR_IN6:
448 			dst = (struct sockaddr *)
449 				&(((struct in6_ifreq *)data)->ifr_addr);
450 			size = sizeof(((struct in6_ifreq *)data)->ifr_addr);
451 			break;
452 #endif /* INET6 */
453 		default:
454 			error = EADDRNOTAVAIL;
455 			goto bad;
456 		}
457 		if (src->sa_len > size)
458 			return EINVAL;
459 		bcopy((caddr_t)src, (caddr_t)dst, src->sa_len);
460 		break;
461 
462 	case SIOCGIFPDSTADDR:
463 #ifdef INET6
464 	case SIOCGIFPDSTADDR_IN6:
465 #endif /* INET6 */
466 		if (sc->gif_pdst == NULL) {
467 			error = EADDRNOTAVAIL;
468 			goto bad;
469 		}
470 		src = sc->gif_pdst;
471 		switch (cmd) {
472 #ifdef INET
473 		case SIOCGIFPDSTADDR:
474 			dst = &ifr->ifr_addr;
475 			size = sizeof(ifr->ifr_addr);
476 			break;
477 #endif /* INET */
478 #ifdef INET6
479 		case SIOCGIFPDSTADDR_IN6:
480 			dst = (struct sockaddr *)
481 				&(((struct in6_ifreq *)data)->ifr_addr);
482 			size = sizeof(((struct in6_ifreq *)data)->ifr_addr);
483 			break;
484 #endif /* INET6 */
485 		default:
486 			error = EADDRNOTAVAIL;
487 			goto bad;
488 		}
489 		if (src->sa_len > size)
490 			return EINVAL;
491 		bcopy((caddr_t)src, (caddr_t)dst, src->sa_len);
492 		break;
493 
494 	case SIOCGLIFPHYADDR:
495 		if (sc->gif_psrc == NULL || sc->gif_pdst == NULL) {
496 			error = EADDRNOTAVAIL;
497 			goto bad;
498 		}
499 
500 		/* copy src */
501 		src = sc->gif_psrc;
502 		dst = (struct sockaddr *)
503 			&(((struct if_laddrreq *)data)->addr);
504 		size = sizeof(((struct if_laddrreq *)data)->addr);
505 		if (src->sa_len > size)
506 			return EINVAL;
507 		bcopy((caddr_t)src, (caddr_t)dst, src->sa_len);
508 
509 		/* copy dst */
510 		src = sc->gif_pdst;
511 		dst = (struct sockaddr *)
512 			&(((struct if_laddrreq *)data)->dstaddr);
513 		size = sizeof(((struct if_laddrreq *)data)->dstaddr);
514 		if (src->sa_len > size)
515 			return EINVAL;
516 		bcopy((caddr_t)src, (caddr_t)dst, src->sa_len);
517 		break;
518 
519 	case SIOCSIFFLAGS:
520 		/* if_ioctl() takes care of it */
521 		break;
522 
523 	default:
524 		error = EINVAL;
525 		break;
526 	}
527  bad:
528 	return error;
529 }
530