1 /* $FreeBSD$ */ 2 /* $KAME: if_stf.c,v 1.73 2001/12/03 11:08:30 keiichi Exp $ */ 3 4 /*- 5 * SPDX-License-Identifier: BSD-3-Clause 6 * 7 * Copyright (C) 2000 WIDE Project. 8 * All rights reserved. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. Neither the name of the project nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 35 /* 36 * 6to4 interface, based on RFC3056. 37 * 38 * 6to4 interface is NOT capable of link-layer (I mean, IPv4) multicasting. 39 * There is no address mapping defined from IPv6 multicast address to IPv4 40 * address. Therefore, we do not have IFF_MULTICAST on the interface. 41 * 42 * Due to the lack of address mapping for link-local addresses, we cannot 43 * throw packets toward link-local addresses (fe80::x). Also, we cannot throw 44 * packets to link-local multicast addresses (ff02::x). 45 * 46 * Here are interesting symptoms due to the lack of link-local address: 47 * 48 * Unicast routing exchange: 49 * - RIPng: Impossible. Uses link-local multicast packet toward ff02::9, 50 * and link-local addresses as nexthop. 51 * - OSPFv6: Impossible. OSPFv6 assumes that there's link-local address 52 * assigned to the link, and makes use of them. Also, HELLO packets use 53 * link-local multicast addresses (ff02::5 and ff02::6). 54 * - BGP4+: Maybe. You can only use global address as nexthop, and global 55 * address as TCP endpoint address. 56 * 57 * Multicast routing protocols: 58 * - PIM: Hello packet cannot be used to discover adjacent PIM routers. 59 * Adjacent PIM routers must be configured manually (is it really spec-wise 60 * correct thing to do?). 61 * 62 * ICMPv6: 63 * - Redirects cannot be used due to the lack of link-local address. 64 * 65 * stf interface does not have, and will not need, a link-local address. 66 * It seems to have no real benefit and does not help the above symptoms much. 67 * Even if we assign link-locals to interface, we cannot really 68 * use link-local unicast/multicast on top of 6to4 cloud (since there's no 69 * encapsulation defined for link-local address), and the above analysis does 70 * not change. RFC3056 does not mandate the assignment of link-local address 71 * either. 72 * 73 * 6to4 interface has security issues. Refer to 74 * http://playground.iijlab.net/i-d/draft-itojun-ipv6-transition-abuse-00.txt 75 * for details. The code tries to filter out some of malicious packets. 76 * Note that there is no way to be 100% secure. 77 */ 78 79 #include <sys/param.h> 80 #include <sys/systm.h> 81 #include <sys/socket.h> 82 #include <sys/sockio.h> 83 #include <sys/mbuf.h> 84 #include <sys/errno.h> 85 #include <sys/kernel.h> 86 #include <sys/lock.h> 87 #include <sys/module.h> 88 #include <sys/proc.h> 89 #include <sys/queue.h> 90 #include <sys/rmlock.h> 91 #include <sys/sysctl.h> 92 #include <machine/cpu.h> 93 94 #include <sys/malloc.h> 95 96 #include <net/if.h> 97 #include <net/if_var.h> 98 #include <net/if_clone.h> 99 #include <net/route.h> 100 #include <net/route/nhop.h> 101 #include <net/netisr.h> 102 #include <net/if_types.h> 103 #include <net/vnet.h> 104 105 #include <netinet/in.h> 106 #include <netinet/in_fib.h> 107 #include <netinet/in_systm.h> 108 #include <netinet/ip.h> 109 #include <netinet/ip_var.h> 110 #include <netinet/in_var.h> 111 112 #include <netinet/ip6.h> 113 #include <netinet6/ip6_var.h> 114 #include <netinet6/in6_var.h> 115 #include <netinet/ip_ecn.h> 116 117 #include <netinet/ip_encap.h> 118 119 #include <machine/stdarg.h> 120 121 #include <net/bpf.h> 122 123 #include <security/mac/mac_framework.h> 124 125 SYSCTL_DECL(_net_link); 126 static SYSCTL_NODE(_net_link, IFT_STF, stf, CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 127 "6to4 Interface"); 128 129 static int stf_permit_rfc1918 = 0; 130 SYSCTL_INT(_net_link_stf, OID_AUTO, permit_rfc1918, CTLFLAG_RWTUN, 131 &stf_permit_rfc1918, 0, "Permit the use of private IPv4 addresses"); 132 133 #define STFUNIT 0 134 135 #define IN6_IS_ADDR_6TO4(x) (ntohs((x)->s6_addr16[0]) == 0x2002) 136 137 /* 138 * XXX: Return a pointer with 16-bit aligned. Don't cast it to 139 * struct in_addr *; use bcopy() instead. 140 */ 141 #define GET_V4(x) (&(x)->s6_addr16[1]) 142 143 struct stf_softc { 144 struct ifnet *sc_ifp; 145 u_int sc_fibnum; 146 const struct encaptab *encap_cookie; 147 }; 148 #define STF2IFP(sc) ((sc)->sc_ifp) 149 150 static const char stfname[] = "stf"; 151 152 static MALLOC_DEFINE(M_STF, stfname, "6to4 Tunnel Interface"); 153 static const int ip_stf_ttl = 40; 154 155 static int in_stf_input(struct mbuf *, int, int, void *); 156 static char *stfnames[] = {"stf0", "stf", "6to4", NULL}; 157 158 static int stfmodevent(module_t, int, void *); 159 static int stf_encapcheck(const struct mbuf *, int, int, void *); 160 static int stf_getsrcifa6(struct ifnet *, struct in6_addr *, struct in6_addr *); 161 static int stf_output(struct ifnet *, struct mbuf *, const struct sockaddr *, 162 struct route *); 163 static int isrfc1918addr(struct in_addr *); 164 static int stf_checkaddr4(struct stf_softc *, struct in_addr *, 165 struct ifnet *); 166 static int stf_checkaddr6(struct stf_softc *, struct in6_addr *, 167 struct ifnet *); 168 static int stf_ioctl(struct ifnet *, u_long, caddr_t); 169 170 static int stf_clone_match(struct if_clone *, const char *); 171 static int stf_clone_create(struct if_clone *, char *, size_t, caddr_t); 172 static int stf_clone_destroy(struct if_clone *, struct ifnet *); 173 static struct if_clone *stf_cloner; 174 175 static const struct encap_config ipv4_encap_cfg = { 176 .proto = IPPROTO_IPV6, 177 .min_length = sizeof(struct ip), 178 .exact_match = (sizeof(in_addr_t) << 3) + 8, 179 .check = stf_encapcheck, 180 .input = in_stf_input 181 }; 182 183 static int 184 stf_clone_match(struct if_clone *ifc, const char *name) 185 { 186 int i; 187 188 for(i = 0; stfnames[i] != NULL; i++) { 189 if (strcmp(stfnames[i], name) == 0) 190 return (1); 191 } 192 193 return (0); 194 } 195 196 static int 197 stf_clone_create(struct if_clone *ifc, char *name, size_t len, caddr_t params) 198 { 199 char *dp; 200 int err, unit, wildcard; 201 struct stf_softc *sc; 202 struct ifnet *ifp; 203 204 err = ifc_name2unit(name, &unit); 205 if (err != 0) 206 return (err); 207 wildcard = (unit < 0); 208 209 /* 210 * We can only have one unit, but since unit allocation is 211 * already locked, we use it to keep from allocating extra 212 * interfaces. 213 */ 214 unit = STFUNIT; 215 err = ifc_alloc_unit(ifc, &unit); 216 if (err != 0) 217 return (err); 218 219 sc = malloc(sizeof(struct stf_softc), M_STF, M_WAITOK | M_ZERO); 220 ifp = STF2IFP(sc) = if_alloc(IFT_STF); 221 if (ifp == NULL) { 222 free(sc, M_STF); 223 ifc_free_unit(ifc, unit); 224 return (ENOSPC); 225 } 226 ifp->if_softc = sc; 227 sc->sc_fibnum = curthread->td_proc->p_fibnum; 228 229 /* 230 * Set the name manually rather then using if_initname because 231 * we don't conform to the default naming convention for interfaces. 232 * In the wildcard case, we need to update the name. 233 */ 234 if (wildcard) { 235 for (dp = name; *dp != '\0'; dp++); 236 if (snprintf(dp, len - (dp-name), "%d", unit) > 237 len - (dp-name) - 1) { 238 /* 239 * This can only be a programmer error and 240 * there's no straightforward way to recover if 241 * it happens. 242 */ 243 panic("if_clone_create(): interface name too long"); 244 } 245 } 246 strlcpy(ifp->if_xname, name, IFNAMSIZ); 247 ifp->if_dname = stfname; 248 ifp->if_dunit = IF_DUNIT_NONE; 249 250 sc->encap_cookie = ip_encap_attach(&ipv4_encap_cfg, sc, M_WAITOK); 251 if (sc->encap_cookie == NULL) { 252 if_printf(ifp, "attach failed\n"); 253 free(sc, M_STF); 254 ifc_free_unit(ifc, unit); 255 return (ENOMEM); 256 } 257 258 ifp->if_mtu = IPV6_MMTU; 259 ifp->if_ioctl = stf_ioctl; 260 ifp->if_output = stf_output; 261 ifp->if_snd.ifq_maxlen = ifqmaxlen; 262 if_attach(ifp); 263 bpfattach(ifp, DLT_NULL, sizeof(u_int32_t)); 264 return (0); 265 } 266 267 static int 268 stf_clone_destroy(struct if_clone *ifc, struct ifnet *ifp) 269 { 270 struct stf_softc *sc = ifp->if_softc; 271 int err __unused; 272 273 err = ip_encap_detach(sc->encap_cookie); 274 KASSERT(err == 0, ("Unexpected error detaching encap_cookie")); 275 bpfdetach(ifp); 276 if_detach(ifp); 277 if_free(ifp); 278 279 free(sc, M_STF); 280 ifc_free_unit(ifc, STFUNIT); 281 282 return (0); 283 } 284 285 static int 286 stfmodevent(module_t mod, int type, void *data) 287 { 288 289 switch (type) { 290 case MOD_LOAD: 291 stf_cloner = if_clone_advanced(stfname, 0, stf_clone_match, 292 stf_clone_create, stf_clone_destroy); 293 break; 294 case MOD_UNLOAD: 295 if_clone_detach(stf_cloner); 296 break; 297 default: 298 return (EOPNOTSUPP); 299 } 300 301 return (0); 302 } 303 304 static moduledata_t stf_mod = { 305 "if_stf", 306 stfmodevent, 307 0 308 }; 309 310 DECLARE_MODULE(if_stf, stf_mod, SI_SUB_PSEUDO, SI_ORDER_ANY); 311 312 static int 313 stf_encapcheck(const struct mbuf *m, int off, int proto, void *arg) 314 { 315 struct ip ip; 316 struct stf_softc *sc; 317 struct in_addr a, b, mask; 318 struct in6_addr addr6, mask6; 319 320 sc = (struct stf_softc *)arg; 321 if (sc == NULL) 322 return 0; 323 324 if ((STF2IFP(sc)->if_flags & IFF_UP) == 0) 325 return 0; 326 327 /* IFF_LINK0 means "no decapsulation" */ 328 if ((STF2IFP(sc)->if_flags & IFF_LINK0) != 0) 329 return 0; 330 331 if (proto != IPPROTO_IPV6) 332 return 0; 333 334 m_copydata(m, 0, sizeof(ip), (caddr_t)&ip); 335 336 if (ip.ip_v != 4) 337 return 0; 338 339 if (stf_getsrcifa6(STF2IFP(sc), &addr6, &mask6) != 0) 340 return (0); 341 342 /* 343 * check if IPv4 dst matches the IPv4 address derived from the 344 * local 6to4 address. 345 * success on: dst = 10.1.1.1, ia6->ia_addr = 2002:0a01:0101:... 346 */ 347 if (bcmp(GET_V4(&addr6), &ip.ip_dst, sizeof(ip.ip_dst)) != 0) 348 return 0; 349 350 /* 351 * check if IPv4 src matches the IPv4 address derived from the 352 * local 6to4 address masked by prefixmask. 353 * success on: src = 10.1.1.1, ia6->ia_addr = 2002:0a00:.../24 354 * fail on: src = 10.1.1.1, ia6->ia_addr = 2002:0b00:.../24 355 */ 356 bzero(&a, sizeof(a)); 357 bcopy(GET_V4(&addr6), &a, sizeof(a)); 358 bcopy(GET_V4(&mask6), &mask, sizeof(mask)); 359 a.s_addr &= mask.s_addr; 360 b = ip.ip_src; 361 b.s_addr &= mask.s_addr; 362 if (a.s_addr != b.s_addr) 363 return 0; 364 365 /* stf interface makes single side match only */ 366 return 32; 367 } 368 369 static int 370 stf_getsrcifa6(struct ifnet *ifp, struct in6_addr *addr, struct in6_addr *mask) 371 { 372 struct rm_priotracker in_ifa_tracker; 373 struct ifaddr *ia; 374 struct in_ifaddr *ia4; 375 struct in6_ifaddr *ia6; 376 struct sockaddr_in6 *sin6; 377 struct in_addr in; 378 379 NET_EPOCH_ASSERT(); 380 381 CK_STAILQ_FOREACH(ia, &ifp->if_addrhead, ifa_link) { 382 if (ia->ifa_addr->sa_family != AF_INET6) 383 continue; 384 sin6 = (struct sockaddr_in6 *)ia->ifa_addr; 385 if (!IN6_IS_ADDR_6TO4(&sin6->sin6_addr)) 386 continue; 387 388 bcopy(GET_V4(&sin6->sin6_addr), &in, sizeof(in)); 389 IN_IFADDR_RLOCK(&in_ifa_tracker); 390 LIST_FOREACH(ia4, INADDR_HASH(in.s_addr), ia_hash) 391 if (ia4->ia_addr.sin_addr.s_addr == in.s_addr) 392 break; 393 IN_IFADDR_RUNLOCK(&in_ifa_tracker); 394 if (ia4 == NULL) 395 continue; 396 397 ia6 = (struct in6_ifaddr *)ia; 398 399 *addr = sin6->sin6_addr; 400 *mask = ia6->ia_prefixmask.sin6_addr; 401 return (0); 402 } 403 404 return (ENOENT); 405 } 406 407 static int 408 stf_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst, 409 struct route *ro) 410 { 411 struct stf_softc *sc; 412 const struct sockaddr_in6 *dst6; 413 struct in_addr in4; 414 const void *ptr; 415 u_int8_t tos; 416 struct ip *ip; 417 struct ip6_hdr *ip6; 418 struct in6_addr addr6, mask6; 419 int error; 420 421 #ifdef MAC 422 error = mac_ifnet_check_transmit(ifp, m); 423 if (error) { 424 m_freem(m); 425 return (error); 426 } 427 #endif 428 429 sc = ifp->if_softc; 430 dst6 = (const struct sockaddr_in6 *)dst; 431 432 /* just in case */ 433 if ((ifp->if_flags & IFF_UP) == 0) { 434 m_freem(m); 435 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 436 return ENETDOWN; 437 } 438 439 /* 440 * If we don't have an ip4 address that match my inner ip6 address, 441 * we shouldn't generate output. Without this check, we'll end up 442 * using wrong IPv4 source. 443 */ 444 if (stf_getsrcifa6(ifp, &addr6, &mask6) != 0) { 445 m_freem(m); 446 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 447 return ENETDOWN; 448 } 449 450 if (m->m_len < sizeof(*ip6)) { 451 m = m_pullup(m, sizeof(*ip6)); 452 if (!m) { 453 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 454 return ENOBUFS; 455 } 456 } 457 ip6 = mtod(m, struct ip6_hdr *); 458 tos = IPV6_TRAFFIC_CLASS(ip6); 459 460 /* 461 * Pickup the right outer dst addr from the list of candidates. 462 * ip6_dst has priority as it may be able to give us shorter IPv4 hops. 463 */ 464 ptr = NULL; 465 if (IN6_IS_ADDR_6TO4(&ip6->ip6_dst)) 466 ptr = GET_V4(&ip6->ip6_dst); 467 else if (IN6_IS_ADDR_6TO4(&dst6->sin6_addr)) 468 ptr = GET_V4(&dst6->sin6_addr); 469 else { 470 m_freem(m); 471 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 472 return ENETUNREACH; 473 } 474 bcopy(ptr, &in4, sizeof(in4)); 475 476 if (bpf_peers_present(ifp->if_bpf)) { 477 /* 478 * We need to prepend the address family as 479 * a four byte field. Cons up a dummy header 480 * to pacify bpf. This is safe because bpf 481 * will only read from the mbuf (i.e., it won't 482 * try to free it or keep a pointer a to it). 483 */ 484 u_int af = AF_INET6; 485 bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m); 486 } 487 488 M_PREPEND(m, sizeof(struct ip), M_NOWAIT); 489 if (m == NULL) { 490 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 491 return ENOBUFS; 492 } 493 ip = mtod(m, struct ip *); 494 495 bzero(ip, sizeof(*ip)); 496 497 bcopy(GET_V4(&addr6), &ip->ip_src, sizeof(ip->ip_src)); 498 bcopy(&in4, &ip->ip_dst, sizeof(ip->ip_dst)); 499 ip->ip_p = IPPROTO_IPV6; 500 ip->ip_ttl = ip_stf_ttl; 501 ip->ip_len = htons(m->m_pkthdr.len); 502 if (ifp->if_flags & IFF_LINK1) 503 ip_ecn_ingress(ECN_ALLOWED, &ip->ip_tos, &tos); 504 else 505 ip_ecn_ingress(ECN_NOCARE, &ip->ip_tos, &tos); 506 507 M_SETFIB(m, sc->sc_fibnum); 508 if_inc_counter(ifp, IFCOUNTER_OPACKETS, 1); 509 error = ip_output(m, NULL, NULL, 0, NULL, NULL); 510 511 return error; 512 } 513 514 static int 515 isrfc1918addr(struct in_addr *in) 516 { 517 /* 518 * returns 1 if private address range: 519 * 10.0.0.0/8 172.16.0.0/12 192.168.0.0/16 520 */ 521 if (stf_permit_rfc1918 == 0 && ( 522 (ntohl(in->s_addr) & 0xff000000) >> 24 == 10 || 523 (ntohl(in->s_addr) & 0xfff00000) >> 16 == 172 * 256 + 16 || 524 (ntohl(in->s_addr) & 0xffff0000) >> 16 == 192 * 256 + 168)) 525 return 1; 526 527 return 0; 528 } 529 530 static int 531 stf_checkaddr4(struct stf_softc *sc, struct in_addr *in, struct ifnet *inifp) 532 { 533 struct rm_priotracker in_ifa_tracker; 534 struct in_ifaddr *ia4; 535 536 /* 537 * reject packets with the following address: 538 * 224.0.0.0/4 0.0.0.0/8 127.0.0.0/8 255.0.0.0/8 539 */ 540 if (IN_MULTICAST(ntohl(in->s_addr))) 541 return -1; 542 switch ((ntohl(in->s_addr) & 0xff000000) >> 24) { 543 case 0: case 127: case 255: 544 return -1; 545 } 546 547 /* 548 * reject packets with private address range. 549 * (requirement from RFC3056 section 2 1st paragraph) 550 */ 551 if (isrfc1918addr(in)) 552 return -1; 553 554 /* 555 * reject packets with broadcast 556 */ 557 IN_IFADDR_RLOCK(&in_ifa_tracker); 558 CK_STAILQ_FOREACH(ia4, &V_in_ifaddrhead, ia_link) { 559 if ((ia4->ia_ifa.ifa_ifp->if_flags & IFF_BROADCAST) == 0) 560 continue; 561 if (in->s_addr == ia4->ia_broadaddr.sin_addr.s_addr) { 562 IN_IFADDR_RUNLOCK(&in_ifa_tracker); 563 return -1; 564 } 565 } 566 IN_IFADDR_RUNLOCK(&in_ifa_tracker); 567 568 /* 569 * perform ingress filter 570 */ 571 if (sc && (STF2IFP(sc)->if_flags & IFF_LINK2) == 0 && inifp) { 572 struct nhop_object *nh; 573 574 NET_EPOCH_ASSERT(); 575 nh = fib4_lookup(sc->sc_fibnum, *in, 0, 0, 0); 576 if (nh == NULL) 577 return (-1); 578 579 if (nh->nh_ifp != inifp) 580 return (-1); 581 } 582 583 return 0; 584 } 585 586 static int 587 stf_checkaddr6(struct stf_softc *sc, struct in6_addr *in6, struct ifnet *inifp) 588 { 589 /* 590 * check 6to4 addresses 591 */ 592 if (IN6_IS_ADDR_6TO4(in6)) { 593 struct in_addr in4; 594 bcopy(GET_V4(in6), &in4, sizeof(in4)); 595 return stf_checkaddr4(sc, &in4, inifp); 596 } 597 598 /* 599 * reject anything that look suspicious. the test is implemented 600 * in ip6_input too, but we check here as well to 601 * (1) reject bad packets earlier, and 602 * (2) to be safe against future ip6_input change. 603 */ 604 if (IN6_IS_ADDR_V4COMPAT(in6) || IN6_IS_ADDR_V4MAPPED(in6)) 605 return -1; 606 607 return 0; 608 } 609 610 static int 611 in_stf_input(struct mbuf *m, int off, int proto, void *arg) 612 { 613 struct stf_softc *sc = arg; 614 struct ip *ip; 615 struct ip6_hdr *ip6; 616 u_int8_t otos, itos; 617 struct ifnet *ifp; 618 619 NET_EPOCH_ASSERT(); 620 621 if (proto != IPPROTO_IPV6) { 622 m_freem(m); 623 return (IPPROTO_DONE); 624 } 625 626 ip = mtod(m, struct ip *); 627 if (sc == NULL || (STF2IFP(sc)->if_flags & IFF_UP) == 0) { 628 m_freem(m); 629 return (IPPROTO_DONE); 630 } 631 632 ifp = STF2IFP(sc); 633 634 #ifdef MAC 635 mac_ifnet_create_mbuf(ifp, m); 636 #endif 637 638 /* 639 * perform sanity check against outer src/dst. 640 * for source, perform ingress filter as well. 641 */ 642 if (stf_checkaddr4(sc, &ip->ip_dst, NULL) < 0 || 643 stf_checkaddr4(sc, &ip->ip_src, m->m_pkthdr.rcvif) < 0) { 644 m_freem(m); 645 return (IPPROTO_DONE); 646 } 647 648 otos = ip->ip_tos; 649 m_adj(m, off); 650 651 if (m->m_len < sizeof(*ip6)) { 652 m = m_pullup(m, sizeof(*ip6)); 653 if (!m) 654 return (IPPROTO_DONE); 655 } 656 ip6 = mtod(m, struct ip6_hdr *); 657 658 /* 659 * perform sanity check against inner src/dst. 660 * for source, perform ingress filter as well. 661 */ 662 if (stf_checkaddr6(sc, &ip6->ip6_dst, NULL) < 0 || 663 stf_checkaddr6(sc, &ip6->ip6_src, m->m_pkthdr.rcvif) < 0) { 664 m_freem(m); 665 return (IPPROTO_DONE); 666 } 667 668 itos = IPV6_TRAFFIC_CLASS(ip6); 669 if ((ifp->if_flags & IFF_LINK1) != 0) 670 ip_ecn_egress(ECN_ALLOWED, &otos, &itos); 671 else 672 ip_ecn_egress(ECN_NOCARE, &otos, &itos); 673 ip6->ip6_flow &= ~htonl(0xff << 20); 674 ip6->ip6_flow |= htonl((u_int32_t)itos << 20); 675 676 m->m_pkthdr.rcvif = ifp; 677 678 if (bpf_peers_present(ifp->if_bpf)) { 679 /* 680 * We need to prepend the address family as 681 * a four byte field. Cons up a dummy header 682 * to pacify bpf. This is safe because bpf 683 * will only read from the mbuf (i.e., it won't 684 * try to free it or keep a pointer a to it). 685 */ 686 u_int32_t af = AF_INET6; 687 bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m); 688 } 689 690 /* 691 * Put the packet to the network layer input queue according to the 692 * specified address family. 693 * See net/if_gif.c for possible issues with packet processing 694 * reorder due to extra queueing. 695 */ 696 if_inc_counter(ifp, IFCOUNTER_IPACKETS, 1); 697 if_inc_counter(ifp, IFCOUNTER_IBYTES, m->m_pkthdr.len); 698 M_SETFIB(m, ifp->if_fib); 699 netisr_dispatch(NETISR_IPV6, m); 700 return (IPPROTO_DONE); 701 } 702 703 static int 704 stf_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data) 705 { 706 struct ifaddr *ifa; 707 struct ifreq *ifr; 708 struct sockaddr_in6 *sin6; 709 struct in_addr addr; 710 int error, mtu; 711 712 error = 0; 713 switch (cmd) { 714 case SIOCSIFADDR: 715 ifa = (struct ifaddr *)data; 716 if (ifa == NULL || ifa->ifa_addr->sa_family != AF_INET6) { 717 error = EAFNOSUPPORT; 718 break; 719 } 720 sin6 = (struct sockaddr_in6 *)ifa->ifa_addr; 721 if (!IN6_IS_ADDR_6TO4(&sin6->sin6_addr)) { 722 error = EINVAL; 723 break; 724 } 725 bcopy(GET_V4(&sin6->sin6_addr), &addr, sizeof(addr)); 726 if (isrfc1918addr(&addr)) { 727 error = EINVAL; 728 break; 729 } 730 731 ifp->if_flags |= IFF_UP; 732 ifp->if_drv_flags |= IFF_DRV_RUNNING; 733 break; 734 735 case SIOCADDMULTI: 736 case SIOCDELMULTI: 737 ifr = (struct ifreq *)data; 738 if (ifr && ifr->ifr_addr.sa_family == AF_INET6) 739 ; 740 else 741 error = EAFNOSUPPORT; 742 break; 743 744 case SIOCGIFMTU: 745 break; 746 747 case SIOCSIFMTU: 748 ifr = (struct ifreq *)data; 749 mtu = ifr->ifr_mtu; 750 /* RFC 4213 3.2 ideal world MTU */ 751 if (mtu < IPV6_MINMTU || mtu > IF_MAXMTU - 20) 752 return (EINVAL); 753 ifp->if_mtu = mtu; 754 break; 755 756 default: 757 error = EINVAL; 758 break; 759 } 760 761 return error; 762 } 763