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: stable/11/sys/net/if_gre.c 332288 2018-04-08 16:54:07Z brooks $"); 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 92static const char grename[] = "gre"; 93static MALLOC_DEFINE(M_GRE, grename, "Generic Routing Encapsulation"); 94static 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 102static VNET_DEFINE(LIST_HEAD(, gre_softc), gre_softc_list); 103#define V_gre_softc_list VNET(gre_softc_list) 104static struct sx gre_ioctl_sx; 105SX_SYSINIT(gre_ioctl_sx, &gre_ioctl_sx, "gre_ioctl"); 106 107static int gre_clone_create(struct if_clone *, int, caddr_t); 108static void gre_clone_destroy(struct ifnet *); 109static VNET_DEFINE(struct if_clone *, gre_cloner); 110#define V_gre_cloner VNET(gre_cloner) 111 112static void gre_qflush(struct ifnet *); 113static int gre_transmit(struct ifnet *, struct mbuf *); 114static int gre_ioctl(struct ifnet *, u_long, caddr_t); 115static int gre_output(struct ifnet *, struct mbuf *, 116 const struct sockaddr *, struct route *); 117 118static void gre_updatehdr(struct gre_softc *); 119static int gre_set_tunnel(struct ifnet *, struct sockaddr *, 120 struct sockaddr *); 121static void gre_delete_tunnel(struct ifnet *); 122 123SYSCTL_DECL(_net_link); 124static 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 138static VNET_DEFINE(int, max_gre_nesting) = MAX_GRE_NEST; 139#define V_max_gre_nesting VNET(max_gre_nesting) 140SYSCTL_INT(_net_link_gre, OID_AUTO, max_nesting, CTLFLAG_RW | CTLFLAG_VNET, 141 &VNET_NAME(max_gre_nesting), 0, "Max nested tunnels"); 142 143static void 144vnet_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} 151VNET_SYSINIT(vnet_gre_init, SI_SUB_PROTO_IFATTACHDOMAIN, SI_ORDER_ANY, 152 vnet_gre_init, NULL); 153 154static void 155vnet_gre_uninit(const void *unused __unused) 156{ 157 158 if_clone_detach(V_gre_cloner); 159 GRE_LIST_LOCK_DESTROY(); 160} 161VNET_SYSUNINIT(vnet_gre_uninit, SI_SUB_PROTO_IFATTACHDOMAIN, SI_ORDER_ANY, 162 vnet_gre_uninit, NULL); 163 164static int 165gre_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 192static void 193gre_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 213static int 214gre_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_data_get_ptr(ifr), &opt, 457 sizeof(opt))) != 0) 458 break; 459 if (sc->gre_key != opt) { 460 GRE_WLOCK(sc); 461 sc->gre_key = opt; 462 gre_updatehdr(sc); 463 GRE_WUNLOCK(sc); 464 } 465 break; 466 case GREGKEY: 467 error = copyout(&sc->gre_key, ifr_data_get_ptr(ifr), 468 sizeof(sc->gre_key)); 469 break; 470 case GRESOPTS: 471 if ((error = priv_check(curthread, PRIV_NET_GRE)) != 0) 472 break; 473 if ((error = copyin(ifr_data_get_ptr(ifr), &opt, 474 sizeof(opt))) != 0) 475 break; 476 if (opt & ~GRE_OPTMASK) 477 error = EINVAL; 478 else { 479 if (sc->gre_options != opt) { 480 GRE_WLOCK(sc); 481 sc->gre_options = opt; 482 gre_updatehdr(sc); 483 GRE_WUNLOCK(sc); 484 } 485 } 486 break; 487 488 case GREGOPTS: 489 error = copyout(&sc->gre_options, ifr_data_get_ptr(ifr), 490 sizeof(sc->gre_options)); 491 break; 492 default: 493 error = EINVAL; 494 break; 495 } 496end: 497 sx_xunlock(&gre_ioctl_sx); 498 return (error); 499} 500 501static void 502gre_updatehdr(struct gre_softc *sc) 503{ 504 struct grehdr *gh = NULL; 505 uint32_t *opts; 506 uint16_t flags; 507 508 GRE_WLOCK_ASSERT(sc); 509 switch (sc->gre_family) { 510#ifdef INET 511 case AF_INET: 512 sc->gre_hlen = sizeof(struct greip); 513 sc->gre_oip.ip_v = IPPROTO_IPV4; 514 sc->gre_oip.ip_hl = sizeof(struct ip) >> 2; 515 sc->gre_oip.ip_p = IPPROTO_GRE; 516 gh = &sc->gre_gihdr->gi_gre; 517 break; 518#endif 519#ifdef INET6 520 case AF_INET6: 521 sc->gre_hlen = sizeof(struct greip6); 522 sc->gre_oip6.ip6_vfc = IPV6_VERSION; 523 sc->gre_oip6.ip6_nxt = IPPROTO_GRE; 524 gh = &sc->gre_gi6hdr->gi6_gre; 525 break; 526#endif 527 default: 528 return; 529 } 530 flags = 0; 531 opts = gh->gre_opts; 532 if (sc->gre_options & GRE_ENABLE_CSUM) { 533 flags |= GRE_FLAGS_CP; 534 sc->gre_hlen += 2 * sizeof(uint16_t); 535 *opts++ = 0; 536 } 537 if (sc->gre_key != 0) { 538 flags |= GRE_FLAGS_KP; 539 sc->gre_hlen += sizeof(uint32_t); 540 *opts++ = htonl(sc->gre_key); 541 } 542 if (sc->gre_options & GRE_ENABLE_SEQ) { 543 flags |= GRE_FLAGS_SP; 544 sc->gre_hlen += sizeof(uint32_t); 545 *opts++ = 0; 546 } else 547 sc->gre_oseq = 0; 548 gh->gre_flags = htons(flags); 549} 550 551static void 552gre_detach(struct gre_softc *sc) 553{ 554 555 sx_assert(&gre_ioctl_sx, SA_XLOCKED); 556 if (sc->gre_ecookie != NULL) 557 encap_detach(sc->gre_ecookie); 558 sc->gre_ecookie = NULL; 559} 560 561static int 562gre_set_tunnel(struct ifnet *ifp, struct sockaddr *src, 563 struct sockaddr *dst) 564{ 565 struct gre_softc *sc, *tsc; 566#ifdef INET6 567 struct ip6_hdr *ip6; 568#endif 569#ifdef INET 570 struct ip *ip; 571#endif 572 void *hdr; 573 int error; 574 575 sx_assert(&gre_ioctl_sx, SA_XLOCKED); 576 GRE_LIST_LOCK(); 577 sc = ifp->if_softc; 578 LIST_FOREACH(tsc, &V_gre_softc_list, gre_list) { 579 if (tsc == sc || tsc->gre_family != src->sa_family) 580 continue; 581#ifdef INET 582 if (tsc->gre_family == AF_INET && 583 tsc->gre_oip.ip_src.s_addr == 584 satosin(src)->sin_addr.s_addr && 585 tsc->gre_oip.ip_dst.s_addr == 586 satosin(dst)->sin_addr.s_addr) { 587 GRE_LIST_UNLOCK(); 588 return (EADDRNOTAVAIL); 589 } 590#endif 591#ifdef INET6 592 if (tsc->gre_family == AF_INET6 && 593 IN6_ARE_ADDR_EQUAL(&tsc->gre_oip6.ip6_src, 594 &satosin6(src)->sin6_addr) && 595 IN6_ARE_ADDR_EQUAL(&tsc->gre_oip6.ip6_dst, 596 &satosin6(dst)->sin6_addr)) { 597 GRE_LIST_UNLOCK(); 598 return (EADDRNOTAVAIL); 599 } 600#endif 601 } 602 GRE_LIST_UNLOCK(); 603 604 switch (src->sa_family) { 605#ifdef INET 606 case AF_INET: 607 hdr = ip = malloc(sizeof(struct greip) + 608 3 * sizeof(uint32_t), M_GRE, M_WAITOK | M_ZERO); 609 ip->ip_src = satosin(src)->sin_addr; 610 ip->ip_dst = satosin(dst)->sin_addr; 611 break; 612#endif 613#ifdef INET6 614 case AF_INET6: 615 hdr = ip6 = malloc(sizeof(struct greip6) + 616 3 * sizeof(uint32_t), M_GRE, M_WAITOK | M_ZERO); 617 ip6->ip6_src = satosin6(src)->sin6_addr; 618 ip6->ip6_dst = satosin6(dst)->sin6_addr; 619 break; 620#endif 621 default: 622 return (EAFNOSUPPORT); 623 } 624 if (sc->gre_family != 0) 625 gre_detach(sc); 626 GRE_WLOCK(sc); 627 if (sc->gre_family != 0) 628 free(sc->gre_hdr, M_GRE); 629 sc->gre_family = src->sa_family; 630 sc->gre_hdr = hdr; 631 sc->gre_oseq = 0; 632 sc->gre_iseq = UINT32_MAX; 633 gre_updatehdr(sc); 634 GRE_WUNLOCK(sc); 635 636 error = 0; 637 switch (src->sa_family) { 638#ifdef INET 639 case AF_INET: 640 error = in_gre_attach(sc); 641 break; 642#endif 643#ifdef INET6 644 case AF_INET6: 645 error = in6_gre_attach(sc); 646 break; 647#endif 648 } 649 if (error == 0) { 650 ifp->if_drv_flags |= IFF_DRV_RUNNING; 651 if_link_state_change(ifp, LINK_STATE_UP); 652 } 653 return (error); 654} 655 656static void 657gre_delete_tunnel(struct ifnet *ifp) 658{ 659 struct gre_softc *sc = ifp->if_softc; 660 int family; 661 662 GRE_WLOCK(sc); 663 family = sc->gre_family; 664 sc->gre_family = 0; 665 GRE_WUNLOCK(sc); 666 if (family != 0) { 667 gre_detach(sc); 668 free(sc->gre_hdr, M_GRE); 669 } 670 ifp->if_drv_flags &= ~IFF_DRV_RUNNING; 671 if_link_state_change(ifp, LINK_STATE_DOWN); 672} 673 674int 675gre_input(struct mbuf **mp, int *offp, int proto) 676{ 677 struct gre_softc *sc; 678 struct grehdr *gh; 679 struct ifnet *ifp; 680 struct mbuf *m; 681 uint32_t *opts; 682#ifdef notyet 683 uint32_t key; 684#endif 685 uint16_t flags; 686 int hlen, isr, af; 687 688 m = *mp; 689 sc = encap_getarg(m); 690 KASSERT(sc != NULL, ("encap_getarg returned NULL")); 691 692 ifp = GRE2IFP(sc); 693 hlen = *offp + sizeof(struct grehdr) + 4 * sizeof(uint32_t); 694 if (m->m_pkthdr.len < hlen) 695 goto drop; 696 if (m->m_len < hlen) { 697 m = m_pullup(m, hlen); 698 if (m == NULL) 699 goto drop; 700 } 701 gh = (struct grehdr *)mtodo(m, *offp); 702 flags = ntohs(gh->gre_flags); 703 if (flags & ~GRE_FLAGS_MASK) 704 goto drop; 705 opts = gh->gre_opts; 706 hlen = 2 * sizeof(uint16_t); 707 if (flags & GRE_FLAGS_CP) { 708 /* reserved1 field must be zero */ 709 if (((uint16_t *)opts)[1] != 0) 710 goto drop; 711 if (in_cksum_skip(m, m->m_pkthdr.len, *offp) != 0) 712 goto drop; 713 hlen += 2 * sizeof(uint16_t); 714 opts++; 715 } 716 if (flags & GRE_FLAGS_KP) { 717#ifdef notyet 718 /* 719 * XXX: The current implementation uses the key only for outgoing 720 * packets. But we can check the key value here, or even in the 721 * encapcheck function. 722 */ 723 key = ntohl(*opts); 724#endif 725 hlen += sizeof(uint32_t); 726 opts++; 727 } 728#ifdef notyet 729 } else 730 key = 0; 731 732 if (sc->gre_key != 0 && (key != sc->gre_key || key != 0)) 733 goto drop; 734#endif 735 if (flags & GRE_FLAGS_SP) { 736#ifdef notyet 737 seq = ntohl(*opts); 738#endif 739 hlen += sizeof(uint32_t); 740 } 741 switch (ntohs(gh->gre_proto)) { 742 case ETHERTYPE_WCCP: 743 /* 744 * For WCCP skip an additional 4 bytes if after GRE header 745 * doesn't follow an IP header. 746 */ 747 if (flags == 0 && (*(uint8_t *)gh->gre_opts & 0xF0) != 0x40) 748 hlen += sizeof(uint32_t); 749 /* FALLTHROUGH */ 750 case ETHERTYPE_IP: 751 isr = NETISR_IP; 752 af = AF_INET; 753 break; 754 case ETHERTYPE_IPV6: 755 isr = NETISR_IPV6; 756 af = AF_INET6; 757 break; 758 default: 759 goto drop; 760 } 761 m_adj(m, *offp + hlen); 762 m_clrprotoflags(m); 763 m->m_pkthdr.rcvif = ifp; 764 M_SETFIB(m, ifp->if_fib); 765#ifdef MAC 766 mac_ifnet_create_mbuf(ifp, m); 767#endif 768 BPF_MTAP2(ifp, &af, sizeof(af), m); 769 if_inc_counter(ifp, IFCOUNTER_IPACKETS, 1); 770 if_inc_counter(ifp, IFCOUNTER_IBYTES, m->m_pkthdr.len); 771 if ((ifp->if_flags & IFF_MONITOR) != 0) 772 m_freem(m); 773 else 774 netisr_dispatch(isr, m); 775 return (IPPROTO_DONE); 776drop: 777 if_inc_counter(ifp, IFCOUNTER_IERRORS, 1); 778 m_freem(m); 779 return (IPPROTO_DONE); 780} 781 782#define MTAG_GRE 1307983903 783static int 784gre_check_nesting(struct ifnet *ifp, struct mbuf *m) 785{ 786 struct m_tag *mtag; 787 int count; 788 789 count = 1; 790 mtag = NULL; 791 while ((mtag = m_tag_locate(m, MTAG_GRE, 0, mtag)) != NULL) { 792 if (*(struct ifnet **)(mtag + 1) == ifp) { 793 log(LOG_NOTICE, "%s: loop detected\n", ifp->if_xname); 794 return (EIO); 795 } 796 count++; 797 } 798 if (count > V_max_gre_nesting) { 799 log(LOG_NOTICE, 800 "%s: if_output recursively called too many times(%d)\n", 801 ifp->if_xname, count); 802 return (EIO); 803 } 804 mtag = m_tag_alloc(MTAG_GRE, 0, sizeof(struct ifnet *), M_NOWAIT); 805 if (mtag == NULL) 806 return (ENOMEM); 807 *(struct ifnet **)(mtag + 1) = ifp; 808 m_tag_prepend(m, mtag); 809 return (0); 810} 811 812static int 813gre_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst, 814 struct route *ro) 815{ 816 uint32_t af; 817 int error; 818 819#ifdef MAC 820 error = mac_ifnet_check_transmit(ifp, m); 821 if (error != 0) 822 goto drop; 823#endif 824 if ((ifp->if_flags & IFF_MONITOR) != 0 || 825 (ifp->if_flags & IFF_UP) == 0) { 826 error = ENETDOWN; 827 goto drop; 828 } 829 830 error = gre_check_nesting(ifp, m); 831 if (error != 0) 832 goto drop; 833 834 m->m_flags &= ~(M_BCAST|M_MCAST); 835 if (dst->sa_family == AF_UNSPEC) 836 bcopy(dst->sa_data, &af, sizeof(af)); 837 else 838 af = dst->sa_family; 839 BPF_MTAP2(ifp, &af, sizeof(af), m); 840 m->m_pkthdr.csum_data = af; /* save af for if_transmit */ 841 return (ifp->if_transmit(ifp, m)); 842drop: 843 m_freem(m); 844 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 845 return (error); 846} 847 848static void 849gre_setseqn(struct grehdr *gh, uint32_t seq) 850{ 851 uint32_t *opts; 852 uint16_t flags; 853 854 opts = gh->gre_opts; 855 flags = ntohs(gh->gre_flags); 856 KASSERT((flags & GRE_FLAGS_SP) != 0, 857 ("gre_setseqn called, but GRE_FLAGS_SP isn't set ")); 858 if (flags & GRE_FLAGS_CP) 859 opts++; 860 if (flags & GRE_FLAGS_KP) 861 opts++; 862 *opts = htonl(seq); 863} 864 865static int 866gre_transmit(struct ifnet *ifp, struct mbuf *m) 867{ 868 GRE_RLOCK_TRACKER; 869 struct gre_softc *sc; 870 struct grehdr *gh; 871 uint32_t iaf, oaf, oseq; 872 int error, hlen, olen, plen; 873 int want_seq, want_csum; 874 875 plen = 0; 876 sc = ifp->if_softc; 877 if (sc == NULL) { 878 error = ENETDOWN; 879 m_freem(m); 880 goto drop; 881 } 882 GRE_RLOCK(sc); 883 if (sc->gre_family == 0) { 884 GRE_RUNLOCK(sc); 885 error = ENETDOWN; 886 m_freem(m); 887 goto drop; 888 } 889 iaf = m->m_pkthdr.csum_data; 890 oaf = sc->gre_family; 891 hlen = sc->gre_hlen; 892 want_seq = (sc->gre_options & GRE_ENABLE_SEQ) != 0; 893 if (want_seq) 894 oseq = sc->gre_oseq++; /* XXX */ 895 else 896 oseq = 0; /* Make compiler happy. */ 897 want_csum = (sc->gre_options & GRE_ENABLE_CSUM) != 0; 898 M_SETFIB(m, sc->gre_fibnum); 899 M_PREPEND(m, hlen, M_NOWAIT); 900 if (m == NULL) { 901 GRE_RUNLOCK(sc); 902 error = ENOBUFS; 903 goto drop; 904 } 905 bcopy(sc->gre_hdr, mtod(m, void *), hlen); 906 GRE_RUNLOCK(sc); 907 switch (oaf) { 908#ifdef INET 909 case AF_INET: 910 olen = sizeof(struct ip); 911 break; 912#endif 913#ifdef INET6 914 case AF_INET6: 915 olen = sizeof(struct ip6_hdr); 916 break; 917#endif 918 default: 919 error = ENETDOWN; 920 goto drop; 921 } 922 gh = (struct grehdr *)mtodo(m, olen); 923 switch (iaf) { 924#ifdef INET 925 case AF_INET: 926 gh->gre_proto = htons(ETHERTYPE_IP); 927 break; 928#endif 929#ifdef INET6 930 case AF_INET6: 931 gh->gre_proto = htons(ETHERTYPE_IPV6); 932 break; 933#endif 934 default: 935 error = ENETDOWN; 936 goto drop; 937 } 938 if (want_seq) 939 gre_setseqn(gh, oseq); 940 if (want_csum) { 941 *(uint16_t *)gh->gre_opts = in_cksum_skip(m, 942 m->m_pkthdr.len, olen); 943 } 944 plen = m->m_pkthdr.len - hlen; 945 switch (oaf) { 946#ifdef INET 947 case AF_INET: 948 error = in_gre_output(m, iaf, hlen); 949 break; 950#endif 951#ifdef INET6 952 case AF_INET6: 953 error = in6_gre_output(m, iaf, hlen); 954 break; 955#endif 956 default: 957 m_freem(m); 958 error = ENETDOWN; 959 } 960drop: 961 if (error) 962 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 963 else { 964 if_inc_counter(ifp, IFCOUNTER_OPACKETS, 1); 965 if_inc_counter(ifp, IFCOUNTER_OBYTES, plen); 966 } 967 return (error); 968} 969 970static void 971gre_qflush(struct ifnet *ifp __unused) 972{ 973 974} 975 976static int 977gremodevent(module_t mod, int type, void *data) 978{ 979 980 switch (type) { 981 case MOD_LOAD: 982 case MOD_UNLOAD: 983 break; 984 default: 985 return (EOPNOTSUPP); 986 } 987 return (0); 988} 989 990static moduledata_t gre_mod = { 991 "if_gre", 992 gremodevent, 993 0 994}; 995 996DECLARE_MODULE(if_gre, gre_mod, SI_SUB_PSEUDO, SI_ORDER_ANY); 997MODULE_VERSION(if_gre, 1); 998