FreeBSD/Linux Kernel Cross Reference
sys/net/if_gre.c
1 /*-
2 * Copyright (c) 1998 The NetBSD Foundation, Inc.
3 * Copyright (c) 2014 Andrey V. Elsukov <ae@FreeBSD.org>
4 * All rights reserved.
5 *
6 * This code is derived from software contributed to The NetBSD Foundation
7 * by Heiko W.Rupp <hwr@pilhuhn.de>
8 *
9 * IPv6-over-GRE contributed by Gert Doering <gert@greenie.muc.de>
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
22 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
23 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
24 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30 * POSSIBILITY OF SUCH DAMAGE.
31 *
32 * $NetBSD: if_gre.c,v 1.49 2003/12/11 00:22:29 itojun Exp $
33 */
34
35 #include <sys/cdefs.h>
36 __FBSDID("$FreeBSD: releng/11.1/sys/net/if_gre.c 317403 2017-04-25 11:19:22Z ae $");
37
38 #include "opt_inet.h"
39 #include "opt_inet6.h"
40
41 #include <sys/param.h>
42 #include <sys/jail.h>
43 #include <sys/kernel.h>
44 #include <sys/lock.h>
45 #include <sys/libkern.h>
46 #include <sys/malloc.h>
47 #include <sys/module.h>
48 #include <sys/mbuf.h>
49 #include <sys/priv.h>
50 #include <sys/proc.h>
51 #include <sys/protosw.h>
52 #include <sys/rmlock.h>
53 #include <sys/socket.h>
54 #include <sys/sockio.h>
55 #include <sys/sx.h>
56 #include <sys/sysctl.h>
57 #include <sys/syslog.h>
58 #include <sys/systm.h>
59
60 #include <net/ethernet.h>
61 #include <net/if.h>
62 #include <net/if_var.h>
63 #include <net/if_clone.h>
64 #include <net/if_types.h>
65 #include <net/netisr.h>
66 #include <net/vnet.h>
67 #include <net/route.h>
68
69 #include <netinet/in.h>
70 #ifdef INET
71 #include <netinet/in_systm.h>
72 #include <netinet/in_var.h>
73 #include <netinet/ip.h>
74 #include <netinet/ip_var.h>
75 #endif
76
77 #ifdef INET6
78 #include <netinet/ip6.h>
79 #include <netinet6/in6_var.h>
80 #include <netinet6/ip6_var.h>
81 #include <netinet6/scope6_var.h>
82 #endif
83
84 #include <netinet/ip_encap.h>
85 #include <net/bpf.h>
86 #include <net/if_gre.h>
87
88 #include <machine/in_cksum.h>
89 #include <security/mac/mac_framework.h>
90
91 #define GREMTU 1476
92 static const char grename[] = "gre";
93 static MALLOC_DEFINE(M_GRE, grename, "Generic Routing Encapsulation");
94 static VNET_DEFINE(struct mtx, gre_mtx);
95 #define V_gre_mtx VNET(gre_mtx)
96 #define GRE_LIST_LOCK_INIT(x) mtx_init(&V_gre_mtx, "gre_mtx", NULL, \
97 MTX_DEF)
98 #define GRE_LIST_LOCK_DESTROY(x) mtx_destroy(&V_gre_mtx)
99 #define GRE_LIST_LOCK(x) mtx_lock(&V_gre_mtx)
100 #define GRE_LIST_UNLOCK(x) mtx_unlock(&V_gre_mtx)
101
102 static VNET_DEFINE(LIST_HEAD(, gre_softc), gre_softc_list);
103 #define V_gre_softc_list VNET(gre_softc_list)
104 static struct sx gre_ioctl_sx;
105 SX_SYSINIT(gre_ioctl_sx, &gre_ioctl_sx, "gre_ioctl");
106
107 static int gre_clone_create(struct if_clone *, int, caddr_t);
108 static void gre_clone_destroy(struct ifnet *);
109 static VNET_DEFINE(struct if_clone *, gre_cloner);
110 #define V_gre_cloner VNET(gre_cloner)
111
112 static void gre_qflush(struct ifnet *);
113 static int gre_transmit(struct ifnet *, struct mbuf *);
114 static int gre_ioctl(struct ifnet *, u_long, caddr_t);
115 static int gre_output(struct ifnet *, struct mbuf *,
116 const struct sockaddr *, struct route *);
117
118 static void gre_updatehdr(struct gre_softc *);
119 static int gre_set_tunnel(struct ifnet *, struct sockaddr *,
120 struct sockaddr *);
121 static void gre_delete_tunnel(struct ifnet *);
122
123 SYSCTL_DECL(_net_link);
124 static SYSCTL_NODE(_net_link, IFT_TUNNEL, gre, CTLFLAG_RW, 0,
125 "Generic Routing Encapsulation");
126 #ifndef MAX_GRE_NEST
127 /*
128 * This macro controls the default upper limitation on nesting of gre tunnels.
129 * Since, setting a large value to this macro with a careless configuration
130 * may introduce system crash, we don't allow any nestings by default.
131 * If you need to configure nested gre tunnels, you can define this macro
132 * in your kernel configuration file. However, if you do so, please be
133 * careful to configure the tunnels so that it won't make a loop.
134 */
135 #define MAX_GRE_NEST 1
136 #endif
137
138 static VNET_DEFINE(int, max_gre_nesting) = MAX_GRE_NEST;
139 #define V_max_gre_nesting VNET(max_gre_nesting)
140 SYSCTL_INT(_net_link_gre, OID_AUTO, max_nesting, CTLFLAG_RW | CTLFLAG_VNET,
141 &VNET_NAME(max_gre_nesting), 0, "Max nested tunnels");
142
143 static void
144 vnet_gre_init(const void *unused __unused)
145 {
146 LIST_INIT(&V_gre_softc_list);
147 GRE_LIST_LOCK_INIT();
148 V_gre_cloner = if_clone_simple(grename, gre_clone_create,
149 gre_clone_destroy, 0);
150 }
151 VNET_SYSINIT(vnet_gre_init, SI_SUB_PROTO_IFATTACHDOMAIN, SI_ORDER_ANY,
152 vnet_gre_init, NULL);
153
154 static void
155 vnet_gre_uninit(const void *unused __unused)
156 {
157
158 if_clone_detach(V_gre_cloner);
159 GRE_LIST_LOCK_DESTROY();
160 }
161 VNET_SYSUNINIT(vnet_gre_uninit, SI_SUB_PROTO_IFATTACHDOMAIN, SI_ORDER_ANY,
162 vnet_gre_uninit, NULL);
163
164 static int
165 gre_clone_create(struct if_clone *ifc, int unit, caddr_t params)
166 {
167 struct gre_softc *sc;
168
169 sc = malloc(sizeof(struct gre_softc), M_GRE, M_WAITOK | M_ZERO);
170 sc->gre_fibnum = curthread->td_proc->p_fibnum;
171 GRE2IFP(sc) = if_alloc(IFT_TUNNEL);
172 GRE_LOCK_INIT(sc);
173 GRE2IFP(sc)->if_softc = sc;
174 if_initname(GRE2IFP(sc), grename, unit);
175
176 GRE2IFP(sc)->if_mtu = GREMTU;
177 GRE2IFP(sc)->if_flags = IFF_POINTOPOINT|IFF_MULTICAST;
178 GRE2IFP(sc)->if_output = gre_output;
179 GRE2IFP(sc)->if_ioctl = gre_ioctl;
180 GRE2IFP(sc)->if_transmit = gre_transmit;
181 GRE2IFP(sc)->if_qflush = gre_qflush;
182 GRE2IFP(sc)->if_capabilities |= IFCAP_LINKSTATE;
183 GRE2IFP(sc)->if_capenable |= IFCAP_LINKSTATE;
184 if_attach(GRE2IFP(sc));
185 bpfattach(GRE2IFP(sc), DLT_NULL, sizeof(u_int32_t));
186 GRE_LIST_LOCK();
187 LIST_INSERT_HEAD(&V_gre_softc_list, sc, gre_list);
188 GRE_LIST_UNLOCK();
189 return (0);
190 }
191
192 static void
193 gre_clone_destroy(struct ifnet *ifp)
194 {
195 struct gre_softc *sc;
196
197 sx_xlock(&gre_ioctl_sx);
198 sc = ifp->if_softc;
199 gre_delete_tunnel(ifp);
200 GRE_LIST_LOCK();
201 LIST_REMOVE(sc, gre_list);
202 GRE_LIST_UNLOCK();
203 bpfdetach(ifp);
204 if_detach(ifp);
205 ifp->if_softc = NULL;
206 sx_xunlock(&gre_ioctl_sx);
207
208 if_free(ifp);
209 GRE_LOCK_DESTROY(sc);
210 free(sc, M_GRE);
211 }
212
213 static int
214 gre_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
215 {
216 GRE_RLOCK_TRACKER;
217 struct ifreq *ifr = (struct ifreq *)data;
218 struct sockaddr *src, *dst;
219 struct gre_softc *sc;
220 #ifdef INET
221 struct sockaddr_in *sin = NULL;
222 #endif
223 #ifdef INET6
224 struct sockaddr_in6 *sin6 = NULL;
225 #endif
226 uint32_t opt;
227 int error;
228
229 switch (cmd) {
230 case SIOCSIFMTU:
231 /* XXX: */
232 if (ifr->ifr_mtu < 576)
233 return (EINVAL);
234 ifp->if_mtu = ifr->ifr_mtu;
235 return (0);
236 case SIOCSIFADDR:
237 ifp->if_flags |= IFF_UP;
238 case SIOCSIFFLAGS:
239 case SIOCADDMULTI:
240 case SIOCDELMULTI:
241 return (0);
242 case GRESADDRS:
243 case GRESADDRD:
244 case GREGADDRS:
245 case GREGADDRD:
246 case GRESPROTO:
247 case GREGPROTO:
248 return (EOPNOTSUPP);
249 }
250 src = dst = NULL;
251 sx_xlock(&gre_ioctl_sx);
252 sc = ifp->if_softc;
253 if (sc == NULL) {
254 error = ENXIO;
255 goto end;
256 }
257 error = 0;
258 switch (cmd) {
259 case SIOCSIFPHYADDR:
260 #ifdef INET6
261 case SIOCSIFPHYADDR_IN6:
262 #endif
263 error = EINVAL;
264 switch (cmd) {
265 #ifdef INET
266 case SIOCSIFPHYADDR:
267 src = (struct sockaddr *)
268 &(((struct in_aliasreq *)data)->ifra_addr);
269 dst = (struct sockaddr *)
270 &(((struct in_aliasreq *)data)->ifra_dstaddr);
271 break;
272 #endif
273 #ifdef INET6
274 case SIOCSIFPHYADDR_IN6:
275 src = (struct sockaddr *)
276 &(((struct in6_aliasreq *)data)->ifra_addr);
277 dst = (struct sockaddr *)
278 &(((struct in6_aliasreq *)data)->ifra_dstaddr);
279 break;
280 #endif
281 default:
282 error = EAFNOSUPPORT;
283 goto end;
284 }
285 /* sa_family must be equal */
286 if (src->sa_family != dst->sa_family ||
287 src->sa_len != dst->sa_len)
288 goto end;
289
290 /* validate sa_len */
291 switch (src->sa_family) {
292 #ifdef INET
293 case AF_INET:
294 if (src->sa_len != sizeof(struct sockaddr_in))
295 goto end;
296 break;
297 #endif
298 #ifdef INET6
299 case AF_INET6:
300 if (src->sa_len != sizeof(struct sockaddr_in6))
301 goto end;
302 break;
303 #endif
304 default:
305 error = EAFNOSUPPORT;
306 goto end;
307 }
308 /* check sa_family looks sane for the cmd */
309 error = EAFNOSUPPORT;
310 switch (cmd) {
311 #ifdef INET
312 case SIOCSIFPHYADDR:
313 if (src->sa_family == AF_INET)
314 break;
315 goto end;
316 #endif
317 #ifdef INET6
318 case SIOCSIFPHYADDR_IN6:
319 if (src->sa_family == AF_INET6)
320 break;
321 goto end;
322 #endif
323 }
324 error = EADDRNOTAVAIL;
325 switch (src->sa_family) {
326 #ifdef INET
327 case AF_INET:
328 if (satosin(src)->sin_addr.s_addr == INADDR_ANY ||
329 satosin(dst)->sin_addr.s_addr == INADDR_ANY)
330 goto end;
331 break;
332 #endif
333 #ifdef INET6
334 case AF_INET6:
335 if (IN6_IS_ADDR_UNSPECIFIED(&satosin6(src)->sin6_addr)
336 ||
337 IN6_IS_ADDR_UNSPECIFIED(&satosin6(dst)->sin6_addr))
338 goto end;
339 /*
340 * Check validity of the scope zone ID of the
341 * addresses, and convert it into the kernel
342 * internal form if necessary.
343 */
344 error = sa6_embedscope(satosin6(src), 0);
345 if (error != 0)
346 goto end;
347 error = sa6_embedscope(satosin6(dst), 0);
348 if (error != 0)
349 goto end;
350 #endif
351 }
352 error = gre_set_tunnel(ifp, src, dst);
353 break;
354 case SIOCDIFPHYADDR:
355 gre_delete_tunnel(ifp);
356 break;
357 case SIOCGIFPSRCADDR:
358 case SIOCGIFPDSTADDR:
359 #ifdef INET6
360 case SIOCGIFPSRCADDR_IN6:
361 case SIOCGIFPDSTADDR_IN6:
362 #endif
363 if (sc->gre_family == 0) {
364 error = EADDRNOTAVAIL;
365 break;
366 }
367 GRE_RLOCK(sc);
368 switch (cmd) {
369 #ifdef INET
370 case SIOCGIFPSRCADDR:
371 case SIOCGIFPDSTADDR:
372 if (sc->gre_family != AF_INET) {
373 error = EADDRNOTAVAIL;
374 break;
375 }
376 sin = (struct sockaddr_in *)&ifr->ifr_addr;
377 memset(sin, 0, sizeof(*sin));
378 sin->sin_family = AF_INET;
379 sin->sin_len = sizeof(*sin);
380 break;
381 #endif
382 #ifdef INET6
383 case SIOCGIFPSRCADDR_IN6:
384 case SIOCGIFPDSTADDR_IN6:
385 if (sc->gre_family != AF_INET6) {
386 error = EADDRNOTAVAIL;
387 break;
388 }
389 sin6 = (struct sockaddr_in6 *)
390 &(((struct in6_ifreq *)data)->ifr_addr);
391 memset(sin6, 0, sizeof(*sin6));
392 sin6->sin6_family = AF_INET6;
393 sin6->sin6_len = sizeof(*sin6);
394 break;
395 #endif
396 }
397 if (error == 0) {
398 switch (cmd) {
399 #ifdef INET
400 case SIOCGIFPSRCADDR:
401 sin->sin_addr = sc->gre_oip.ip_src;
402 break;
403 case SIOCGIFPDSTADDR:
404 sin->sin_addr = sc->gre_oip.ip_dst;
405 break;
406 #endif
407 #ifdef INET6
408 case SIOCGIFPSRCADDR_IN6:
409 sin6->sin6_addr = sc->gre_oip6.ip6_src;
410 break;
411 case SIOCGIFPDSTADDR_IN6:
412 sin6->sin6_addr = sc->gre_oip6.ip6_dst;
413 break;
414 #endif
415 }
416 }
417 GRE_RUNLOCK(sc);
418 if (error != 0)
419 break;
420 switch (cmd) {
421 #ifdef INET
422 case SIOCGIFPSRCADDR:
423 case SIOCGIFPDSTADDR:
424 error = prison_if(curthread->td_ucred,
425 (struct sockaddr *)sin);
426 if (error != 0)
427 memset(sin, 0, sizeof(*sin));
428 break;
429 #endif
430 #ifdef INET6
431 case SIOCGIFPSRCADDR_IN6:
432 case SIOCGIFPDSTADDR_IN6:
433 error = prison_if(curthread->td_ucred,
434 (struct sockaddr *)sin6);
435 if (error == 0)
436 error = sa6_recoverscope(sin6);
437 if (error != 0)
438 memset(sin6, 0, sizeof(*sin6));
439 #endif
440 }
441 break;
442 case SIOCGTUNFIB:
443 ifr->ifr_fib = sc->gre_fibnum;
444 break;
445 case SIOCSTUNFIB:
446 if ((error = priv_check(curthread, PRIV_NET_GRE)) != 0)
447 break;
448 if (ifr->ifr_fib >= rt_numfibs)
449 error = EINVAL;
450 else
451 sc->gre_fibnum = ifr->ifr_fib;
452 break;
453 case GRESKEY:
454 if ((error = priv_check(curthread, PRIV_NET_GRE)) != 0)
455 break;
456 if ((error = copyin(ifr->ifr_data, &opt, sizeof(opt))) != 0)
457 break;
458 if (sc->gre_key != opt) {
459 GRE_WLOCK(sc);
460 sc->gre_key = opt;
461 gre_updatehdr(sc);
462 GRE_WUNLOCK(sc);
463 }
464 break;
465 case GREGKEY:
466 error = copyout(&sc->gre_key, ifr->ifr_data,
467 sizeof(sc->gre_key));
468 break;
469 case GRESOPTS:
470 if ((error = priv_check(curthread, PRIV_NET_GRE)) != 0)
471 break;
472 if ((error = copyin(ifr->ifr_data, &opt, sizeof(opt))) != 0)
473 break;
474 if (opt & ~GRE_OPTMASK)
475 error = EINVAL;
476 else {
477 if (sc->gre_options != opt) {
478 GRE_WLOCK(sc);
479 sc->gre_options = opt;
480 gre_updatehdr(sc);
481 GRE_WUNLOCK(sc);
482 }
483 }
484 break;
485
486 case GREGOPTS:
487 error = copyout(&sc->gre_options, ifr->ifr_data,
488 sizeof(sc->gre_options));
489 break;
490 default:
491 error = EINVAL;
492 break;
493 }
494 end:
495 sx_xunlock(&gre_ioctl_sx);
496 return (error);
497 }
498
499 static void
500 gre_updatehdr(struct gre_softc *sc)
501 {
502 struct grehdr *gh = NULL;
503 uint32_t *opts;
504 uint16_t flags;
505
506 GRE_WLOCK_ASSERT(sc);
507 switch (sc->gre_family) {
508 #ifdef INET
509 case AF_INET:
510 sc->gre_hlen = sizeof(struct greip);
511 sc->gre_oip.ip_v = IPPROTO_IPV4;
512 sc->gre_oip.ip_hl = sizeof(struct ip) >> 2;
513 sc->gre_oip.ip_p = IPPROTO_GRE;
514 gh = &sc->gre_gihdr->gi_gre;
515 break;
516 #endif
517 #ifdef INET6
518 case AF_INET6:
519 sc->gre_hlen = sizeof(struct greip6);
520 sc->gre_oip6.ip6_vfc = IPV6_VERSION;
521 sc->gre_oip6.ip6_nxt = IPPROTO_GRE;
522 gh = &sc->gre_gi6hdr->gi6_gre;
523 break;
524 #endif
525 default:
526 return;
527 }
528 flags = 0;
529 opts = gh->gre_opts;
530 if (sc->gre_options & GRE_ENABLE_CSUM) {
531 flags |= GRE_FLAGS_CP;
532 sc->gre_hlen += 2 * sizeof(uint16_t);
533 *opts++ = 0;
534 }
535 if (sc->gre_key != 0) {
536 flags |= GRE_FLAGS_KP;
537 sc->gre_hlen += sizeof(uint32_t);
538 *opts++ = htonl(sc->gre_key);
539 }
540 if (sc->gre_options & GRE_ENABLE_SEQ) {
541 flags |= GRE_FLAGS_SP;
542 sc->gre_hlen += sizeof(uint32_t);
543 *opts++ = 0;
544 } else
545 sc->gre_oseq = 0;
546 gh->gre_flags = htons(flags);
547 }
548
549 static void
550 gre_detach(struct gre_softc *sc)
551 {
552
553 sx_assert(&gre_ioctl_sx, SA_XLOCKED);
554 if (sc->gre_ecookie != NULL)
555 encap_detach(sc->gre_ecookie);
556 sc->gre_ecookie = NULL;
557 }
558
559 static int
560 gre_set_tunnel(struct ifnet *ifp, struct sockaddr *src,
561 struct sockaddr *dst)
562 {
563 struct gre_softc *sc, *tsc;
564 #ifdef INET6
565 struct ip6_hdr *ip6;
566 #endif
567 #ifdef INET
568 struct ip *ip;
569 #endif
570 void *hdr;
571 int error;
572
573 sx_assert(&gre_ioctl_sx, SA_XLOCKED);
574 GRE_LIST_LOCK();
575 sc = ifp->if_softc;
576 LIST_FOREACH(tsc, &V_gre_softc_list, gre_list) {
577 if (tsc == sc || tsc->gre_family != src->sa_family)
578 continue;
579 #ifdef INET
580 if (tsc->gre_family == AF_INET &&
581 tsc->gre_oip.ip_src.s_addr ==
582 satosin(src)->sin_addr.s_addr &&
583 tsc->gre_oip.ip_dst.s_addr ==
584 satosin(dst)->sin_addr.s_addr) {
585 GRE_LIST_UNLOCK();
586 return (EADDRNOTAVAIL);
587 }
588 #endif
589 #ifdef INET6
590 if (tsc->gre_family == AF_INET6 &&
591 IN6_ARE_ADDR_EQUAL(&tsc->gre_oip6.ip6_src,
592 &satosin6(src)->sin6_addr) &&
593 IN6_ARE_ADDR_EQUAL(&tsc->gre_oip6.ip6_dst,
594 &satosin6(dst)->sin6_addr)) {
595 GRE_LIST_UNLOCK();
596 return (EADDRNOTAVAIL);
597 }
598 #endif
599 }
600 GRE_LIST_UNLOCK();
601
602 switch (src->sa_family) {
603 #ifdef INET
604 case AF_INET:
605 hdr = ip = malloc(sizeof(struct greip) +
606 3 * sizeof(uint32_t), M_GRE, M_WAITOK | M_ZERO);
607 ip->ip_src = satosin(src)->sin_addr;
608 ip->ip_dst = satosin(dst)->sin_addr;
609 break;
610 #endif
611 #ifdef INET6
612 case AF_INET6:
613 hdr = ip6 = malloc(sizeof(struct greip6) +
614 3 * sizeof(uint32_t), M_GRE, M_WAITOK | M_ZERO);
615 ip6->ip6_src = satosin6(src)->sin6_addr;
616 ip6->ip6_dst = satosin6(dst)->sin6_addr;
617 break;
618 #endif
619 default:
620 return (EAFNOSUPPORT);
621 }
622 if (sc->gre_family != 0)
623 gre_detach(sc);
624 GRE_WLOCK(sc);
625 if (sc->gre_family != 0)
626 free(sc->gre_hdr, M_GRE);
627 sc->gre_family = src->sa_family;
628 sc->gre_hdr = hdr;
629 sc->gre_oseq = 0;
630 sc->gre_iseq = UINT32_MAX;
631 gre_updatehdr(sc);
632 GRE_WUNLOCK(sc);
633
634 error = 0;
635 switch (src->sa_family) {
636 #ifdef INET
637 case AF_INET:
638 error = in_gre_attach(sc);
639 break;
640 #endif
641 #ifdef INET6
642 case AF_INET6:
643 error = in6_gre_attach(sc);
644 break;
645 #endif
646 }
647 if (error == 0) {
648 ifp->if_drv_flags |= IFF_DRV_RUNNING;
649 if_link_state_change(ifp, LINK_STATE_UP);
650 }
651 return (error);
652 }
653
654 static void
655 gre_delete_tunnel(struct ifnet *ifp)
656 {
657 struct gre_softc *sc = ifp->if_softc;
658 int family;
659
660 GRE_WLOCK(sc);
661 family = sc->gre_family;
662 sc->gre_family = 0;
663 GRE_WUNLOCK(sc);
664 if (family != 0) {
665 gre_detach(sc);
666 free(sc->gre_hdr, M_GRE);
667 }
668 ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
669 if_link_state_change(ifp, LINK_STATE_DOWN);
670 }
671
672 int
673 gre_input(struct mbuf **mp, int *offp, int proto)
674 {
675 struct gre_softc *sc;
676 struct grehdr *gh;
677 struct ifnet *ifp;
678 struct mbuf *m;
679 uint32_t *opts;
680 #ifdef notyet
681 uint32_t key;
682 #endif
683 uint16_t flags;
684 int hlen, isr, af;
685
686 m = *mp;
687 sc = encap_getarg(m);
688 KASSERT(sc != NULL, ("encap_getarg returned NULL"));
689
690 ifp = GRE2IFP(sc);
691 hlen = *offp + sizeof(struct grehdr) + 4 * sizeof(uint32_t);
692 if (m->m_pkthdr.len < hlen)
693 goto drop;
694 if (m->m_len < hlen) {
695 m = m_pullup(m, hlen);
696 if (m == NULL)
697 goto drop;
698 }
699 gh = (struct grehdr *)mtodo(m, *offp);
700 flags = ntohs(gh->gre_flags);
701 if (flags & ~GRE_FLAGS_MASK)
702 goto drop;
703 opts = gh->gre_opts;
704 hlen = 2 * sizeof(uint16_t);
705 if (flags & GRE_FLAGS_CP) {
706 /* reserved1 field must be zero */
707 if (((uint16_t *)opts)[1] != 0)
708 goto drop;
709 if (in_cksum_skip(m, m->m_pkthdr.len, *offp) != 0)
710 goto drop;
711 hlen += 2 * sizeof(uint16_t);
712 opts++;
713 }
714 if (flags & GRE_FLAGS_KP) {
715 #ifdef notyet
716 /*
717 * XXX: The current implementation uses the key only for outgoing
718 * packets. But we can check the key value here, or even in the
719 * encapcheck function.
720 */
721 key = ntohl(*opts);
722 #endif
723 hlen += sizeof(uint32_t);
724 opts++;
725 }
726 #ifdef notyet
727 } else
728 key = 0;
729
730 if (sc->gre_key != 0 && (key != sc->gre_key || key != 0))
731 goto drop;
732 #endif
733 if (flags & GRE_FLAGS_SP) {
734 #ifdef notyet
735 seq = ntohl(*opts);
736 #endif
737 hlen += sizeof(uint32_t);
738 }
739 switch (ntohs(gh->gre_proto)) {
740 case ETHERTYPE_WCCP:
741 /*
742 * For WCCP skip an additional 4 bytes if after GRE header
743 * doesn't follow an IP header.
744 */
745 if (flags == 0 && (*(uint8_t *)gh->gre_opts & 0xF0) != 0x40)
746 hlen += sizeof(uint32_t);
747 /* FALLTHROUGH */
748 case ETHERTYPE_IP:
749 isr = NETISR_IP;
750 af = AF_INET;
751 break;
752 case ETHERTYPE_IPV6:
753 isr = NETISR_IPV6;
754 af = AF_INET6;
755 break;
756 default:
757 goto drop;
758 }
759 m_adj(m, *offp + hlen);
760 m_clrprotoflags(m);
761 m->m_pkthdr.rcvif = ifp;
762 M_SETFIB(m, ifp->if_fib);
763 #ifdef MAC
764 mac_ifnet_create_mbuf(ifp, m);
765 #endif
766 BPF_MTAP2(ifp, &af, sizeof(af), m);
767 if_inc_counter(ifp, IFCOUNTER_IPACKETS, 1);
768 if_inc_counter(ifp, IFCOUNTER_IBYTES, m->m_pkthdr.len);
769 if ((ifp->if_flags & IFF_MONITOR) != 0)
770 m_freem(m);
771 else
772 netisr_dispatch(isr, m);
773 return (IPPROTO_DONE);
774 drop:
775 if_inc_counter(ifp, IFCOUNTER_IERRORS, 1);
776 m_freem(m);
777 return (IPPROTO_DONE);
778 }
779
780 #define MTAG_GRE 1307983903
781 static int
782 gre_check_nesting(struct ifnet *ifp, struct mbuf *m)
783 {
784 struct m_tag *mtag;
785 int count;
786
787 count = 1;
788 mtag = NULL;
789 while ((mtag = m_tag_locate(m, MTAG_GRE, 0, mtag)) != NULL) {
790 if (*(struct ifnet **)(mtag + 1) == ifp) {
791 log(LOG_NOTICE, "%s: loop detected\n", ifp->if_xname);
792 return (EIO);
793 }
794 count++;
795 }
796 if (count > V_max_gre_nesting) {
797 log(LOG_NOTICE,
798 "%s: if_output recursively called too many times(%d)\n",
799 ifp->if_xname, count);
800 return (EIO);
801 }
802 mtag = m_tag_alloc(MTAG_GRE, 0, sizeof(struct ifnet *), M_NOWAIT);
803 if (mtag == NULL)
804 return (ENOMEM);
805 *(struct ifnet **)(mtag + 1) = ifp;
806 m_tag_prepend(m, mtag);
807 return (0);
808 }
809
810 static int
811 gre_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst,
812 struct route *ro)
813 {
814 uint32_t af;
815 int error;
816
817 #ifdef MAC
818 error = mac_ifnet_check_transmit(ifp, m);
819 if (error != 0)
820 goto drop;
821 #endif
822 if ((ifp->if_flags & IFF_MONITOR) != 0 ||
823 (ifp->if_flags & IFF_UP) == 0) {
824 error = ENETDOWN;
825 goto drop;
826 }
827
828 error = gre_check_nesting(ifp, m);
829 if (error != 0)
830 goto drop;
831
832 m->m_flags &= ~(M_BCAST|M_MCAST);
833 if (dst->sa_family == AF_UNSPEC)
834 bcopy(dst->sa_data, &af, sizeof(af));
835 else
836 af = dst->sa_family;
837 BPF_MTAP2(ifp, &af, sizeof(af), m);
838 m->m_pkthdr.csum_data = af; /* save af for if_transmit */
839 return (ifp->if_transmit(ifp, m));
840 drop:
841 m_freem(m);
842 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1);
843 return (error);
844 }
845
846 static void
847 gre_setseqn(struct grehdr *gh, uint32_t seq)
848 {
849 uint32_t *opts;
850 uint16_t flags;
851
852 opts = gh->gre_opts;
853 flags = ntohs(gh->gre_flags);
854 KASSERT((flags & GRE_FLAGS_SP) != 0,
855 ("gre_setseqn called, but GRE_FLAGS_SP isn't set "));
856 if (flags & GRE_FLAGS_CP)
857 opts++;
858 if (flags & GRE_FLAGS_KP)
859 opts++;
860 *opts = htonl(seq);
861 }
862
863 static int
864 gre_transmit(struct ifnet *ifp, struct mbuf *m)
865 {
866 GRE_RLOCK_TRACKER;
867 struct gre_softc *sc;
868 struct grehdr *gh;
869 uint32_t iaf, oaf, oseq;
870 int error, hlen, olen, plen;
871 int want_seq, want_csum;
872
873 plen = 0;
874 sc = ifp->if_softc;
875 if (sc == NULL) {
876 error = ENETDOWN;
877 m_freem(m);
878 goto drop;
879 }
880 GRE_RLOCK(sc);
881 if (sc->gre_family == 0) {
882 GRE_RUNLOCK(sc);
883 error = ENETDOWN;
884 m_freem(m);
885 goto drop;
886 }
887 iaf = m->m_pkthdr.csum_data;
888 oaf = sc->gre_family;
889 hlen = sc->gre_hlen;
890 want_seq = (sc->gre_options & GRE_ENABLE_SEQ) != 0;
891 if (want_seq)
892 oseq = sc->gre_oseq++; /* XXX */
893 else
894 oseq = 0; /* Make compiler happy. */
895 want_csum = (sc->gre_options & GRE_ENABLE_CSUM) != 0;
896 M_SETFIB(m, sc->gre_fibnum);
897 M_PREPEND(m, hlen, M_NOWAIT);
898 if (m == NULL) {
899 GRE_RUNLOCK(sc);
900 error = ENOBUFS;
901 goto drop;
902 }
903 bcopy(sc->gre_hdr, mtod(m, void *), hlen);
904 GRE_RUNLOCK(sc);
905 switch (oaf) {
906 #ifdef INET
907 case AF_INET:
908 olen = sizeof(struct ip);
909 break;
910 #endif
911 #ifdef INET6
912 case AF_INET6:
913 olen = sizeof(struct ip6_hdr);
914 break;
915 #endif
916 default:
917 error = ENETDOWN;
918 goto drop;
919 }
920 gh = (struct grehdr *)mtodo(m, olen);
921 switch (iaf) {
922 #ifdef INET
923 case AF_INET:
924 gh->gre_proto = htons(ETHERTYPE_IP);
925 break;
926 #endif
927 #ifdef INET6
928 case AF_INET6:
929 gh->gre_proto = htons(ETHERTYPE_IPV6);
930 break;
931 #endif
932 default:
933 error = ENETDOWN;
934 goto drop;
935 }
936 if (want_seq)
937 gre_setseqn(gh, oseq);
938 if (want_csum) {
939 *(uint16_t *)gh->gre_opts = in_cksum_skip(m,
940 m->m_pkthdr.len, olen);
941 }
942 plen = m->m_pkthdr.len - hlen;
943 switch (oaf) {
944 #ifdef INET
945 case AF_INET:
946 error = in_gre_output(m, iaf, hlen);
947 break;
948 #endif
949 #ifdef INET6
950 case AF_INET6:
951 error = in6_gre_output(m, iaf, hlen);
952 break;
953 #endif
954 default:
955 m_freem(m);
956 error = ENETDOWN;
957 }
958 drop:
959 if (error)
960 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1);
961 else {
962 if_inc_counter(ifp, IFCOUNTER_OPACKETS, 1);
963 if_inc_counter(ifp, IFCOUNTER_OBYTES, plen);
964 }
965 return (error);
966 }
967
968 static void
969 gre_qflush(struct ifnet *ifp __unused)
970 {
971
972 }
973
974 static int
975 gremodevent(module_t mod, int type, void *data)
976 {
977
978 switch (type) {
979 case MOD_LOAD:
980 case MOD_UNLOAD:
981 break;
982 default:
983 return (EOPNOTSUPP);
984 }
985 return (0);
986 }
987
988 static moduledata_t gre_mod = {
989 "if_gre",
990 gremodevent,
991 0
992 };
993
994 DECLARE_MODULE(if_gre, gre_mod, SI_SUB_PSEUDO, SI_ORDER_ANY);
995 MODULE_VERSION(if_gre, 1);
Cache object: 3b5c8715b85fa138579d8a09f7e0c284
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