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("$FreeBSD$");
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_clone.h>
63 #include <net/if_var.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
90 #include <security/mac/mac_framework.h>
91 #define GREMTU 1500
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 = sc->gre_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 break;
235 case SIOCSIFADDR:
236 ifp->if_flags |= IFF_UP;
237 case SIOCSIFFLAGS:
238 case SIOCADDMULTI:
239 case SIOCDELMULTI:
240 return (0);
241 case GRESADDRS:
242 case GRESADDRD:
243 case GREGADDRS:
244 case GREGADDRD:
245 case GRESPROTO:
246 case GREGPROTO:
247 return (EOPNOTSUPP);
248 }
249 src = dst = NULL;
250 sx_xlock(&gre_ioctl_sx);
251 sc = ifp->if_softc;
252 if (sc == NULL) {
253 error = ENXIO;
254 goto end;
255 }
256 error = 0;
257 switch (cmd) {
258 case SIOCSIFMTU:
259 GRE_WLOCK(sc);
260 sc->gre_mtu = ifr->ifr_mtu;
261 gre_updatehdr(sc);
262 GRE_WUNLOCK(sc);
263 goto end;
264 case SIOCSIFPHYADDR:
265 #ifdef INET6
266 case SIOCSIFPHYADDR_IN6:
267 #endif
268 error = EINVAL;
269 switch (cmd) {
270 #ifdef INET
271 case SIOCSIFPHYADDR:
272 src = (struct sockaddr *)
273 &(((struct in_aliasreq *)data)->ifra_addr);
274 dst = (struct sockaddr *)
275 &(((struct in_aliasreq *)data)->ifra_dstaddr);
276 break;
277 #endif
278 #ifdef INET6
279 case SIOCSIFPHYADDR_IN6:
280 src = (struct sockaddr *)
281 &(((struct in6_aliasreq *)data)->ifra_addr);
282 dst = (struct sockaddr *)
283 &(((struct in6_aliasreq *)data)->ifra_dstaddr);
284 break;
285 #endif
286 default:
287 error = EAFNOSUPPORT;
288 goto end;
289 }
290 /* sa_family must be equal */
291 if (src->sa_family != dst->sa_family ||
292 src->sa_len != dst->sa_len)
293 goto end;
294
295 /* validate sa_len */
296 switch (src->sa_family) {
297 #ifdef INET
298 case AF_INET:
299 if (src->sa_len != sizeof(struct sockaddr_in))
300 goto end;
301 break;
302 #endif
303 #ifdef INET6
304 case AF_INET6:
305 if (src->sa_len != sizeof(struct sockaddr_in6))
306 goto end;
307 break;
308 #endif
309 default:
310 error = EAFNOSUPPORT;
311 goto end;
312 }
313 /* check sa_family looks sane for the cmd */
314 error = EAFNOSUPPORT;
315 switch (cmd) {
316 #ifdef INET
317 case SIOCSIFPHYADDR:
318 if (src->sa_family == AF_INET)
319 break;
320 goto end;
321 #endif
322 #ifdef INET6
323 case SIOCSIFPHYADDR_IN6:
324 if (src->sa_family == AF_INET6)
325 break;
326 goto end;
327 #endif
328 }
329 error = EADDRNOTAVAIL;
330 switch (src->sa_family) {
331 #ifdef INET
332 case AF_INET:
333 if (satosin(src)->sin_addr.s_addr == INADDR_ANY ||
334 satosin(dst)->sin_addr.s_addr == INADDR_ANY)
335 goto end;
336 break;
337 #endif
338 #ifdef INET6
339 case AF_INET6:
340 if (IN6_IS_ADDR_UNSPECIFIED(&satosin6(src)->sin6_addr)
341 ||
342 IN6_IS_ADDR_UNSPECIFIED(&satosin6(dst)->sin6_addr))
343 goto end;
344 /*
345 * Check validity of the scope zone ID of the
346 * addresses, and convert it into the kernel
347 * internal form if necessary.
348 */
349 error = sa6_embedscope(satosin6(src), 0);
350 if (error != 0)
351 goto end;
352 error = sa6_embedscope(satosin6(dst), 0);
353 if (error != 0)
354 goto end;
355 #endif
356 };
357 error = gre_set_tunnel(ifp, src, dst);
358 break;
359 case SIOCDIFPHYADDR:
360 gre_delete_tunnel(ifp);
361 break;
362 case SIOCGIFPSRCADDR:
363 case SIOCGIFPDSTADDR:
364 #ifdef INET6
365 case SIOCGIFPSRCADDR_IN6:
366 case SIOCGIFPDSTADDR_IN6:
367 #endif
368 if (sc->gre_family == 0) {
369 error = EADDRNOTAVAIL;
370 break;
371 }
372 GRE_RLOCK(sc);
373 switch (cmd) {
374 #ifdef INET
375 case SIOCGIFPSRCADDR:
376 case SIOCGIFPDSTADDR:
377 if (sc->gre_family != AF_INET) {
378 error = EADDRNOTAVAIL;
379 break;
380 }
381 sin = (struct sockaddr_in *)&ifr->ifr_addr;
382 memset(sin, 0, sizeof(*sin));
383 sin->sin_family = AF_INET;
384 sin->sin_len = sizeof(*sin);
385 break;
386 #endif
387 #ifdef INET6
388 case SIOCGIFPSRCADDR_IN6:
389 case SIOCGIFPDSTADDR_IN6:
390 if (sc->gre_family != AF_INET6) {
391 error = EADDRNOTAVAIL;
392 break;
393 }
394 sin6 = (struct sockaddr_in6 *)
395 &(((struct in6_ifreq *)data)->ifr_addr);
396 memset(sin6, 0, sizeof(*sin6));
397 sin6->sin6_family = AF_INET6;
398 sin6->sin6_len = sizeof(*sin6);
399 break;
400 #endif
401 }
402 if (error == 0) {
403 switch (cmd) {
404 #ifdef INET
405 case SIOCGIFPSRCADDR:
406 sin->sin_addr = sc->gre_oip.ip_src;
407 break;
408 case SIOCGIFPDSTADDR:
409 sin->sin_addr = sc->gre_oip.ip_dst;
410 break;
411 #endif
412 #ifdef INET6
413 case SIOCGIFPSRCADDR_IN6:
414 sin6->sin6_addr = sc->gre_oip6.ip6_src;
415 break;
416 case SIOCGIFPDSTADDR_IN6:
417 sin6->sin6_addr = sc->gre_oip6.ip6_dst;
418 break;
419 #endif
420 }
421 }
422 GRE_RUNLOCK(sc);
423 if (error != 0)
424 break;
425 switch (cmd) {
426 #ifdef INET
427 case SIOCGIFPSRCADDR:
428 case SIOCGIFPDSTADDR:
429 error = prison_if(curthread->td_ucred,
430 (struct sockaddr *)sin);
431 if (error != 0)
432 memset(sin, 0, sizeof(*sin));
433 break;
434 #endif
435 #ifdef INET6
436 case SIOCGIFPSRCADDR_IN6:
437 case SIOCGIFPDSTADDR_IN6:
438 error = prison_if(curthread->td_ucred,
439 (struct sockaddr *)sin6);
440 if (error == 0)
441 error = sa6_recoverscope(sin6);
442 if (error != 0)
443 memset(sin6, 0, sizeof(*sin6));
444 #endif
445 }
446 break;
447 case SIOCGTUNFIB:
448 ifr->ifr_fib = sc->gre_fibnum;
449 break;
450 case SIOCSTUNFIB:
451 if ((error = priv_check(curthread, PRIV_NET_GRE)) != 0)
452 break;
453 if (ifr->ifr_fib >= rt_numfibs)
454 error = EINVAL;
455 else
456 sc->gre_fibnum = ifr->ifr_fib;
457 break;
458 case GRESKEY:
459 if ((error = priv_check(curthread, PRIV_NET_GRE)) != 0)
460 break;
461 if ((error = copyin(ifr->ifr_data, &opt, sizeof(opt))) != 0)
462 break;
463 if (sc->gre_key != opt) {
464 GRE_WLOCK(sc);
465 sc->gre_key = opt;
466 gre_updatehdr(sc);
467 GRE_WUNLOCK(sc);
468 }
469 break;
470 case GREGKEY:
471 error = copyout(&sc->gre_key, ifr->ifr_data,
472 sizeof(sc->gre_key));
473 break;
474 case GRESOPTS:
475 if ((error = priv_check(curthread, PRIV_NET_GRE)) != 0)
476 break;
477 if ((error = copyin(ifr->ifr_data, &opt, sizeof(opt))) != 0)
478 break;
479 if (opt & ~GRE_OPTMASK)
480 error = EINVAL;
481 else {
482 if (sc->gre_options != opt) {
483 GRE_WLOCK(sc);
484 sc->gre_options = opt;
485 gre_updatehdr(sc);
486 GRE_WUNLOCK(sc);
487 }
488 }
489 break;
490
491 case GREGOPTS:
492 error = copyout(&sc->gre_options, ifr->ifr_data,
493 sizeof(sc->gre_options));
494 break;
495 default:
496 error = EINVAL;
497 break;
498 }
499 end:
500 sx_xunlock(&gre_ioctl_sx);
501 return (error);
502 }
503
504 static void
505 gre_updatehdr(struct gre_softc *sc)
506 {
507 struct grehdr *gh = NULL;
508 uint32_t *opts;
509 uint16_t flags;
510
511 GRE_WLOCK_ASSERT(sc);
512 switch (sc->gre_family) {
513 #ifdef INET
514 case AF_INET:
515 sc->gre_hlen = sizeof(struct greip);
516 sc->gre_oip.ip_v = IPPROTO_IPV4;
517 sc->gre_oip.ip_hl = sizeof(struct ip) >> 2;
518 sc->gre_oip.ip_p = IPPROTO_GRE;
519 gh = &sc->gre_gihdr->gi_gre;
520 break;
521 #endif
522 #ifdef INET6
523 case AF_INET6:
524 sc->gre_hlen = sizeof(struct greip6);
525 sc->gre_oip6.ip6_vfc = IPV6_VERSION;
526 sc->gre_oip6.ip6_nxt = IPPROTO_GRE;
527 gh = &sc->gre_gi6hdr->gi6_gre;
528 break;
529 #endif
530 default:
531 return;
532 }
533 flags = 0;
534 opts = gh->gre_opts;
535 if (sc->gre_options & GRE_ENABLE_CSUM) {
536 flags |= GRE_FLAGS_CP;
537 sc->gre_hlen += 2 * sizeof(uint16_t);
538 *opts++ = 0;
539 }
540 if (sc->gre_key != 0) {
541 flags |= GRE_FLAGS_KP;
542 sc->gre_hlen += sizeof(uint32_t);
543 *opts++ = htonl(sc->gre_key);
544 }
545 if (sc->gre_options & GRE_ENABLE_SEQ) {
546 flags |= GRE_FLAGS_SP;
547 sc->gre_hlen += sizeof(uint32_t);
548 *opts++ = 0;
549 } else
550 sc->gre_oseq = 0;
551 gh->gre_flags = htons(flags);
552 GRE2IFP(sc)->if_mtu = sc->gre_mtu - sc->gre_hlen;
553 }
554
555 static void
556 gre_detach(struct gre_softc *sc)
557 {
558
559 sx_assert(&gre_ioctl_sx, SA_XLOCKED);
560 if (sc->gre_ecookie != NULL)
561 encap_detach(sc->gre_ecookie);
562 sc->gre_ecookie = NULL;
563 }
564
565 static int
566 gre_set_tunnel(struct ifnet *ifp, struct sockaddr *src,
567 struct sockaddr *dst)
568 {
569 struct gre_softc *sc, *tsc;
570 #ifdef INET6
571 struct ip6_hdr *ip6;
572 #endif
573 #ifdef INET
574 struct ip *ip;
575 #endif
576 void *hdr;
577 int error;
578
579 sx_assert(&gre_ioctl_sx, SA_XLOCKED);
580 GRE_LIST_LOCK();
581 sc = ifp->if_softc;
582 LIST_FOREACH(tsc, &V_gre_softc_list, gre_list) {
583 if (tsc == sc || tsc->gre_family != src->sa_family)
584 continue;
585 #ifdef INET
586 if (tsc->gre_family == AF_INET &&
587 tsc->gre_oip.ip_src.s_addr ==
588 satosin(src)->sin_addr.s_addr &&
589 tsc->gre_oip.ip_dst.s_addr ==
590 satosin(dst)->sin_addr.s_addr) {
591 GRE_LIST_UNLOCK();
592 return (EADDRNOTAVAIL);
593 }
594 #endif
595 #ifdef INET6
596 if (tsc->gre_family == AF_INET6 &&
597 IN6_ARE_ADDR_EQUAL(&tsc->gre_oip6.ip6_src,
598 &satosin6(src)->sin6_addr) &&
599 IN6_ARE_ADDR_EQUAL(&tsc->gre_oip6.ip6_dst,
600 &satosin6(dst)->sin6_addr)) {
601 GRE_LIST_UNLOCK();
602 return (EADDRNOTAVAIL);
603 }
604 #endif
605 }
606 GRE_LIST_UNLOCK();
607
608 error = 0;
609 switch (src->sa_family) {
610 #ifdef INET
611 case AF_INET:
612 hdr = ip = malloc(sizeof(struct greip) +
613 3 * sizeof(uint32_t), M_GRE, M_WAITOK | M_ZERO);
614 ip->ip_src = satosin(src)->sin_addr;
615 ip->ip_dst = satosin(dst)->sin_addr;
616 break;
617 #endif
618 #ifdef INET6
619 case AF_INET6:
620 hdr = ip6 = malloc(sizeof(struct greip6) +
621 3 * sizeof(uint32_t), M_GRE, M_WAITOK | M_ZERO);
622 ip6->ip6_src = satosin6(src)->sin6_addr;
623 ip6->ip6_dst = satosin6(dst)->sin6_addr;
624 break;
625 #endif
626 default:
627 return (EAFNOSUPPORT);
628 }
629 if (sc->gre_family != 0)
630 gre_detach(sc);
631 GRE_WLOCK(sc);
632 if (sc->gre_family != 0)
633 free(sc->gre_hdr, M_GRE);
634 sc->gre_family = src->sa_family;
635 sc->gre_hdr = hdr;
636 sc->gre_oseq = 0;
637 sc->gre_iseq = UINT32_MAX;
638 gre_updatehdr(sc);
639 GRE_WUNLOCK(sc);
640
641 switch (src->sa_family) {
642 #ifdef INET
643 case AF_INET:
644 error = in_gre_attach(sc);
645 break;
646 #endif
647 #ifdef INET6
648 case AF_INET6:
649 error = in6_gre_attach(sc);
650 break;
651 #endif
652 }
653 if (error == 0) {
654 ifp->if_drv_flags |= IFF_DRV_RUNNING;
655 if_link_state_change(ifp, LINK_STATE_UP);
656 }
657 return (error);
658 }
659
660 static void
661 gre_delete_tunnel(struct ifnet *ifp)
662 {
663 struct gre_softc *sc = ifp->if_softc;
664 int family;
665
666 GRE_WLOCK(sc);
667 family = sc->gre_family;
668 sc->gre_family = 0;
669 GRE_WUNLOCK(sc);
670 if (family != 0) {
671 gre_detach(sc);
672 free(sc->gre_hdr, M_GRE);
673 }
674 ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
675 if_link_state_change(ifp, LINK_STATE_DOWN);
676 }
677
678 int
679 gre_input(struct mbuf **mp, int *offp, int proto)
680 {
681 struct gre_softc *sc;
682 struct grehdr *gh;
683 struct ifnet *ifp;
684 struct mbuf *m;
685 uint32_t *opts;
686 #ifdef notyet
687 uint32_t key;
688 #endif
689 uint16_t flags;
690 int hlen, isr, af;
691
692 m = *mp;
693 sc = encap_getarg(m);
694 KASSERT(sc != NULL, ("encap_getarg returned NULL"));
695
696 ifp = GRE2IFP(sc);
697 hlen = *offp + sizeof(struct grehdr) + 4 * sizeof(uint32_t);
698 if (m->m_pkthdr.len < hlen)
699 goto drop;
700 if (m->m_len < hlen) {
701 m = m_pullup(m, hlen);
702 if (m == NULL)
703 goto drop;
704 }
705 gh = (struct grehdr *)mtodo(m, *offp);
706 flags = ntohs(gh->gre_flags);
707 if (flags & ~GRE_FLAGS_MASK)
708 goto drop;
709 opts = gh->gre_opts;
710 hlen = 2 * sizeof(uint16_t);
711 if (flags & GRE_FLAGS_CP) {
712 /* reserved1 field must be zero */
713 if (((uint16_t *)opts)[1] != 0)
714 goto drop;
715 if (in_cksum_skip(m, m->m_pkthdr.len, *offp) != 0)
716 goto drop;
717 hlen += 2 * sizeof(uint16_t);
718 opts++;
719 }
720 if (flags & GRE_FLAGS_KP) {
721 #ifdef notyet
722 /*
723 * XXX: The current implementation uses the key only for outgoing
724 * packets. But we can check the key value here, or even in the
725 * encapcheck function.
726 */
727 key = ntohl(*opts);
728 #endif
729 hlen += sizeof(uint32_t);
730 opts++;
731 }
732 #ifdef notyet
733 } else
734 key = 0;
735 if (sc->gre_key != 0 && (key != sc->gre_key || key != 0))
736 goto drop;
737 #endif
738 if (flags & GRE_FLAGS_SP) {
739 #ifdef notyet
740 seq = ntohl(*opts);
741 #endif
742 hlen += sizeof(uint32_t);
743 }
744 switch (ntohs(gh->gre_proto)) {
745 case ETHERTYPE_WCCP:
746 /*
747 * For WCCP skip an additional 4 bytes if after GRE header
748 * doesn't follow an IP header.
749 */
750 if (flags == 0 && (*(uint8_t *)gh->gre_opts & 0xF0) != 0x40)
751 hlen += sizeof(uint32_t);
752 /* FALLTHROUGH */
753 case ETHERTYPE_IP:
754 isr = NETISR_IP;
755 af = AF_INET;
756 break;
757 case ETHERTYPE_IPV6:
758 isr = NETISR_IPV6;
759 af = AF_INET6;
760 break;
761 default:
762 goto drop;
763 }
764 m_adj(m, *offp + hlen);
765 m_clrprotoflags(m);
766 m->m_pkthdr.rcvif = ifp;
767 M_SETFIB(m, ifp->if_fib);
768 #ifdef MAC
769 mac_ifnet_create_mbuf(ifp, m);
770 #endif
771 BPF_MTAP2(ifp, &af, sizeof(af), m);
772 ifp->if_ipackets++;
773 ifp->if_ibytes += m->m_pkthdr.len;
774 if ((ifp->if_flags & IFF_MONITOR) != 0)
775 m_freem(m);
776 else
777 netisr_dispatch(isr, m);
778 return (IPPROTO_DONE);
779 drop:
780 ifp->if_ierrors++;
781 m_freem(m);
782 return (IPPROTO_DONE);
783 }
784
785 #define MTAG_GRE 1307983903
786 static int
787 gre_check_nesting(struct ifnet *ifp, struct mbuf *m)
788 {
789 struct m_tag *mtag;
790 int count;
791
792 count = 1;
793 mtag = NULL;
794 while ((mtag = m_tag_locate(m, MTAG_GRE, 0, mtag)) != NULL) {
795 if (*(struct ifnet **)(mtag + 1) == ifp) {
796 log(LOG_NOTICE, "%s: loop detected\n", ifp->if_xname);
797 return (EIO);
798 }
799 count++;
800 }
801 if (count > V_max_gre_nesting) {
802 log(LOG_NOTICE,
803 "%s: if_output recursively called too many times(%d)\n",
804 ifp->if_xname, count);
805 return (EIO);
806 }
807 mtag = m_tag_alloc(MTAG_GRE, 0, sizeof(struct ifnet *), M_NOWAIT);
808 if (mtag == NULL)
809 return (ENOMEM);
810 *(struct ifnet **)(mtag + 1) = ifp;
811 m_tag_prepend(m, mtag);
812 return (0);
813 }
814
815 static int
816 gre_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst,
817 struct route *ro)
818 {
819 uint32_t af;
820 int error;
821
822 #ifdef MAC
823 error = mac_ifnet_check_transmit(ifp, m);
824 if (error != 0)
825 goto drop;
826 #endif
827 if ((ifp->if_flags & IFF_MONITOR) != 0 ||
828 (ifp->if_flags & IFF_UP) == 0) {
829 error = ENETDOWN;
830 goto drop;
831 }
832
833 error = gre_check_nesting(ifp, m);
834 if (error != 0)
835 goto drop;
836
837 m->m_flags &= ~(M_BCAST|M_MCAST);
838 if (dst->sa_family == AF_UNSPEC)
839 bcopy(dst->sa_data, &af, sizeof(af));
840 else
841 af = dst->sa_family;
842 BPF_MTAP2(ifp, &af, sizeof(af), m);
843 m->m_pkthdr.csum_data = af; /* save af for if_transmit */
844 return (ifp->if_transmit(ifp, m));
845 drop:
846 m_freem(m);
847 ifp->if_oerrors++;
848 return (error);
849 }
850
851 static void
852 gre_setseqn(struct grehdr *gh, uint32_t seq)
853 {
854 uint32_t *opts;
855 uint16_t flags;
856
857 opts = gh->gre_opts;
858 flags = ntohs(gh->gre_flags);
859 KASSERT((flags & GRE_FLAGS_SP) != 0,
860 ("gre_setseqn called, but GRE_FLAGS_SP isn't set "));
861 if (flags & GRE_FLAGS_CP)
862 opts++;
863 if (flags & GRE_FLAGS_KP)
864 opts++;
865 *opts = htonl(seq);
866 }
867
868 static int
869 gre_transmit(struct ifnet *ifp, struct mbuf *m)
870 {
871 GRE_RLOCK_TRACKER;
872 struct gre_softc *sc;
873 struct grehdr *gh;
874 uint32_t iaf, oaf, oseq;
875 int error, hlen, olen, plen;
876 int want_seq, want_csum;
877
878 plen = 0;
879 sc = ifp->if_softc;
880 if (sc == NULL) {
881 error = ENETDOWN;
882 m_freem(m);
883 goto drop;
884 }
885 GRE_RLOCK(sc);
886 if (sc->gre_family == 0) {
887 GRE_RUNLOCK(sc);
888 error = ENETDOWN;
889 m_freem(m);
890 goto drop;
891 }
892 iaf = m->m_pkthdr.csum_data;
893 oaf = sc->gre_family;
894 hlen = sc->gre_hlen;
895 want_seq = (sc->gre_options & GRE_ENABLE_SEQ) != 0;
896 if (want_seq)
897 oseq = sc->gre_oseq++;
898 else
899 oseq = 0; /* Make compiler happy. */
900 want_csum = (sc->gre_options & GRE_ENABLE_CSUM) != 0;
901 M_SETFIB(m, sc->gre_fibnum);
902 M_PREPEND(m, hlen, M_NOWAIT);
903 if (m == NULL) {
904 GRE_RUNLOCK(sc);
905 error = ENOBUFS;
906 goto drop;
907 }
908 bcopy(sc->gre_hdr, mtod(m, void *), hlen);
909 GRE_RUNLOCK(sc);
910 switch (oaf) {
911 #ifdef INET
912 case AF_INET:
913 olen = sizeof(struct ip);
914 break;
915 #endif
916 #ifdef INET6
917 case AF_INET6:
918 olen = sizeof(struct ip6_hdr);
919 break;
920 #endif
921 default:
922 error = ENETDOWN;
923 goto drop;
924 }
925 gh = (struct grehdr *)mtodo(m, olen);
926 switch (iaf) {
927 #ifdef INET
928 case AF_INET:
929 gh->gre_proto = htons(ETHERTYPE_IP);
930 break;
931 #endif
932 #ifdef INET6
933 case AF_INET6:
934 gh->gre_proto = htons(ETHERTYPE_IPV6);
935 break;
936 #endif
937 default:
938 error = ENETDOWN;
939 goto drop;
940 }
941 if (want_seq)
942 gre_setseqn(gh, oseq);
943 if (want_csum) {
944 *(uint16_t *)gh->gre_opts = in_cksum_skip(m,
945 m->m_pkthdr.len, olen);
946 }
947 plen = m->m_pkthdr.len - hlen;
948 switch (oaf) {
949 #ifdef INET
950 case AF_INET:
951 error = in_gre_output(m, iaf, hlen);
952 break;
953 #endif
954 #ifdef INET6
955 case AF_INET6:
956 error = in6_gre_output(m, iaf, hlen);
957 break;
958 #endif
959 default:
960 m_freem(m);
961 error = ENETDOWN;
962 };
963 drop:
964 if (error)
965 ifp->if_oerrors++;
966 else {
967 ifp->if_opackets++;
968 ifp->if_obytes += plen;
969 }
970 return (error);
971 }
972
973 static void
974 gre_qflush(struct ifnet *ifp __unused)
975 {
976
977 }
978
979 static int
980 gremodevent(module_t mod, int type, void *data)
981 {
982
983 switch (type) {
984 case MOD_LOAD:
985 case MOD_UNLOAD:
986 break;
987 default:
988 return (EOPNOTSUPP);
989 }
990 return (0);
991 }
992
993 static moduledata_t gre_mod = {
994 "if_gre",
995 gremodevent,
996 0
997 };
998
999 DECLARE_MODULE(if_gre, gre_mod, SI_SUB_PSEUDO, SI_ORDER_ANY);
1000 MODULE_VERSION(if_gre, 1);
Cache object: 0e831c11a44bd055c19ce9a59f63490f
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