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/sysctl.h> 91 #include <machine/cpu.h> 92 93 #include <sys/malloc.h> 94 95 #include <net/if.h> 96 #include <net/if_var.h> 97 #include <net/if_clone.h> 98 #include <net/route.h> 99 #include <net/route/nhop.h> 100 #include <net/netisr.h> 101 #include <net/if_types.h> 102 #include <net/vnet.h> 103 104 #include <netinet/in.h> 105 #include <netinet/in_fib.h> 106 #include <netinet/in_systm.h> 107 #include <netinet/ip.h> 108 #include <netinet/ip_var.h> 109 #include <netinet/in_var.h> 110 111 #include <netinet/ip6.h> 112 #include <netinet6/ip6_var.h> 113 #include <netinet6/in6_var.h> 114 #include <netinet/ip_ecn.h> 115 116 #include <netinet/ip_encap.h> 117 118 #include <machine/stdarg.h> 119 120 #include <net/bpf.h> 121 122 #include <security/mac/mac_framework.h> 123 124 SYSCTL_DECL(_net_link); 125 static SYSCTL_NODE(_net_link, IFT_STF, stf, CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 126 "6to4 Interface"); 127 128 static int stf_permit_rfc1918 = 0; 129 SYSCTL_INT(_net_link_stf, OID_AUTO, permit_rfc1918, CTLFLAG_RWTUN, 130 &stf_permit_rfc1918, 0, "Permit the use of private IPv4 addresses"); 131 132 #define STFUNIT 0 133 134 #define IN6_IS_ADDR_6TO4(x) (ntohs((x)->s6_addr16[0]) == 0x2002) 135 136 /* 137 * XXX: Return a pointer with 16-bit aligned. Don't cast it to 138 * struct in_addr *; use bcopy() instead. 139 */ 140 #define GET_V4(x) (&(x)->s6_addr16[1]) 141 142 struct stf_softc { 143 struct ifnet *sc_ifp; 144 u_int sc_fibnum; 145 const struct encaptab *encap_cookie; 146 }; 147 #define STF2IFP(sc) ((sc)->sc_ifp) 148 149 static const char stfname[] = "stf"; 150 151 static MALLOC_DEFINE(M_STF, stfname, "6to4 Tunnel Interface"); 152 static const int ip_stf_ttl = 40; 153 154 static int in_stf_input(struct mbuf *, int, int, void *); 155 static char *stfnames[] = {"stf0", "stf", "6to4", NULL}; 156 157 static int stfmodevent(module_t, int, void *); 158 static int stf_encapcheck(const struct mbuf *, int, int, void *); 159 static int stf_getsrcifa6(struct ifnet *, struct in6_addr *, struct in6_addr *); 160 static int stf_output(struct ifnet *, struct mbuf *, const struct sockaddr *, 161 struct route *); 162 static int isrfc1918addr(struct in_addr *); 163 static int stf_checkaddr4(struct stf_softc *, struct in_addr *, 164 struct ifnet *); 165 static int stf_checkaddr6(struct stf_softc *, struct in6_addr *, 166 struct ifnet *); 167 static int stf_ioctl(struct ifnet *, u_long, caddr_t); 168 169 static int stf_clone_match(struct if_clone *, const char *); 170 static int stf_clone_create(struct if_clone *, char *, size_t, caddr_t); 171 static int stf_clone_destroy(struct if_clone *, struct ifnet *); 172 VNET_DEFINE_STATIC(struct if_clone *, stf_cloner); 173 #define V_stf_cloner VNET(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 void 286 vnet_stf_init(const void *unused __unused) 287 { 288 V_stf_cloner = if_clone_advanced(stfname, 0, stf_clone_match, 289 stf_clone_create, stf_clone_destroy); 290 } 291 VNET_SYSINIT(vnet_stf_init, SI_SUB_PSEUDO, SI_ORDER_ANY, vnet_stf_init, NULL); 292 293 static void 294 vnet_stf_uninit(const void *unused __unused) 295 { 296 if_clone_detach(V_stf_cloner); 297 V_stf_cloner = NULL; 298 } 299 VNET_SYSUNINIT(vnet_stf_uninit, SI_SUB_PSEUDO, SI_ORDER_ANY, vnet_stf_uninit, 300 NULL); 301 302 static int 303 stfmodevent(module_t mod, int type, void *data) 304 { 305 306 switch (type) { 307 case MOD_LOAD: 308 /* Done in vnet_stf_init() */ 309 break; 310 case MOD_UNLOAD: 311 /* Done in vnet_stf_uninit() */ 312 break; 313 default: 314 return (EOPNOTSUPP); 315 } 316 317 return (0); 318 } 319 320 static moduledata_t stf_mod = { 321 "if_stf", 322 stfmodevent, 323 0 324 }; 325 326 DECLARE_MODULE(if_stf, stf_mod, SI_SUB_PSEUDO, SI_ORDER_ANY); 327 328 static int 329 stf_encapcheck(const struct mbuf *m, int off, int proto, void *arg) 330 { 331 struct ip ip; 332 struct stf_softc *sc; 333 struct in_addr a, b, mask; 334 struct in6_addr addr6, mask6; 335 336 sc = (struct stf_softc *)arg; 337 if (sc == NULL) 338 return (0); 339 340 if ((STF2IFP(sc)->if_flags & IFF_UP) == 0) 341 return (0); 342 343 /* IFF_LINK0 means "no decapsulation" */ 344 if ((STF2IFP(sc)->if_flags & IFF_LINK0) != 0) 345 return (0); 346 347 if (proto != IPPROTO_IPV6) 348 return (0); 349 350 m_copydata(m, 0, sizeof(ip), (caddr_t)&ip); 351 352 if (ip.ip_v != 4) 353 return (0); 354 355 if (stf_getsrcifa6(STF2IFP(sc), &addr6, &mask6) != 0) 356 return (0); 357 358 /* 359 * check if IPv4 dst matches the IPv4 address derived from the 360 * local 6to4 address. 361 * success on: dst = 10.1.1.1, ia6->ia_addr = 2002:0a01:0101:... 362 */ 363 if (bcmp(GET_V4(&addr6), &ip.ip_dst, sizeof(ip.ip_dst)) != 0) 364 return (0); 365 366 /* 367 * check if IPv4 src matches the IPv4 address derived from the 368 * local 6to4 address masked by prefixmask. 369 * success on: src = 10.1.1.1, ia6->ia_addr = 2002:0a00:.../24 370 * fail on: src = 10.1.1.1, ia6->ia_addr = 2002:0b00:.../24 371 */ 372 bzero(&a, sizeof(a)); 373 bcopy(GET_V4(&addr6), &a, sizeof(a)); 374 bcopy(GET_V4(&mask6), &mask, sizeof(mask)); 375 a.s_addr &= mask.s_addr; 376 b = ip.ip_src; 377 b.s_addr &= mask.s_addr; 378 if (a.s_addr != b.s_addr) 379 return (0); 380 381 /* stf interface makes single side match only */ 382 return (32); 383 } 384 385 static int 386 stf_getsrcifa6(struct ifnet *ifp, struct in6_addr *addr, struct in6_addr *mask) 387 { 388 struct ifaddr *ia; 389 struct in_ifaddr *ia4; 390 struct in6_ifaddr *ia6; 391 struct sockaddr_in6 *sin6; 392 struct in_addr in; 393 394 NET_EPOCH_ASSERT(); 395 396 CK_STAILQ_FOREACH(ia, &ifp->if_addrhead, ifa_link) { 397 if (ia->ifa_addr->sa_family != AF_INET6) 398 continue; 399 sin6 = (struct sockaddr_in6 *)ia->ifa_addr; 400 if (!IN6_IS_ADDR_6TO4(&sin6->sin6_addr)) 401 continue; 402 403 bcopy(GET_V4(&sin6->sin6_addr), &in, sizeof(in)); 404 CK_LIST_FOREACH(ia4, INADDR_HASH(in.s_addr), ia_hash) 405 if (ia4->ia_addr.sin_addr.s_addr == in.s_addr) 406 break; 407 if (ia4 == NULL) 408 continue; 409 410 ia6 = (struct in6_ifaddr *)ia; 411 412 *addr = sin6->sin6_addr; 413 *mask = ia6->ia_prefixmask.sin6_addr; 414 return (0); 415 } 416 417 return (ENOENT); 418 } 419 420 static int 421 stf_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst, 422 struct route *ro) 423 { 424 struct stf_softc *sc; 425 const struct sockaddr_in6 *dst6; 426 struct in_addr in4; 427 const void *ptr; 428 u_int8_t tos; 429 struct ip *ip; 430 struct ip6_hdr *ip6; 431 struct in6_addr addr6, mask6; 432 int error; 433 434 #ifdef MAC 435 error = mac_ifnet_check_transmit(ifp, m); 436 if (error) { 437 m_freem(m); 438 return (error); 439 } 440 #endif 441 442 sc = ifp->if_softc; 443 dst6 = (const struct sockaddr_in6 *)dst; 444 445 /* just in case */ 446 if ((ifp->if_flags & IFF_UP) == 0) { 447 m_freem(m); 448 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 449 return (ENETDOWN); 450 } 451 452 /* 453 * If we don't have an ip4 address that match my inner ip6 address, 454 * we shouldn't generate output. Without this check, we'll end up 455 * using wrong IPv4 source. 456 */ 457 if (stf_getsrcifa6(ifp, &addr6, &mask6) != 0) { 458 m_freem(m); 459 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 460 return (ENETDOWN); 461 } 462 463 if (m->m_len < sizeof(*ip6)) { 464 m = m_pullup(m, sizeof(*ip6)); 465 if (!m) { 466 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 467 return (ENOBUFS); 468 } 469 } 470 ip6 = mtod(m, struct ip6_hdr *); 471 tos = IPV6_TRAFFIC_CLASS(ip6); 472 473 /* 474 * Pickup the right outer dst addr from the list of candidates. 475 * ip6_dst has priority as it may be able to give us shorter IPv4 hops. 476 */ 477 ptr = NULL; 478 if (IN6_IS_ADDR_6TO4(&ip6->ip6_dst)) 479 ptr = GET_V4(&ip6->ip6_dst); 480 else if (IN6_IS_ADDR_6TO4(&dst6->sin6_addr)) 481 ptr = GET_V4(&dst6->sin6_addr); 482 else { 483 m_freem(m); 484 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 485 return (ENETUNREACH); 486 } 487 bcopy(ptr, &in4, sizeof(in4)); 488 489 if (bpf_peers_present(ifp->if_bpf)) { 490 /* 491 * We need to prepend the address family as 492 * a four byte field. Cons up a dummy header 493 * to pacify bpf. This is safe because bpf 494 * will only read from the mbuf (i.e., it won't 495 * try to free it or keep a pointer a to it). 496 */ 497 u_int af = AF_INET6; 498 bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m); 499 } 500 501 M_PREPEND(m, sizeof(struct ip), M_NOWAIT); 502 if (m == NULL) { 503 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 504 return (ENOBUFS); 505 } 506 ip = mtod(m, struct ip *); 507 508 bzero(ip, sizeof(*ip)); 509 510 bcopy(GET_V4(&addr6), &ip->ip_src, sizeof(ip->ip_src)); 511 bcopy(&in4, &ip->ip_dst, sizeof(ip->ip_dst)); 512 ip->ip_p = IPPROTO_IPV6; 513 ip->ip_ttl = ip_stf_ttl; 514 ip->ip_len = htons(m->m_pkthdr.len); 515 if (ifp->if_flags & IFF_LINK1) 516 ip_ecn_ingress(ECN_ALLOWED, &ip->ip_tos, &tos); 517 else 518 ip_ecn_ingress(ECN_NOCARE, &ip->ip_tos, &tos); 519 520 M_SETFIB(m, sc->sc_fibnum); 521 if_inc_counter(ifp, IFCOUNTER_OPACKETS, 1); 522 error = ip_output(m, NULL, NULL, 0, NULL, NULL); 523 524 return (error); 525 } 526 527 static int 528 isrfc1918addr(struct in_addr *in) 529 { 530 /* 531 * returns 1 if private address range: 532 * 10.0.0.0/8 172.16.0.0/12 192.168.0.0/16 533 */ 534 if (stf_permit_rfc1918 == 0 && ( 535 (ntohl(in->s_addr) & 0xff000000) >> 24 == 10 || 536 (ntohl(in->s_addr) & 0xfff00000) >> 16 == 172 * 256 + 16 || 537 (ntohl(in->s_addr) & 0xffff0000) >> 16 == 192 * 256 + 168)) 538 return (1); 539 540 return (0); 541 } 542 543 static int 544 stf_checkaddr4(struct stf_softc *sc, struct in_addr *in, struct ifnet *inifp) 545 { 546 struct in_ifaddr *ia4; 547 548 /* 549 * reject packets with the following address: 550 * 224.0.0.0/4 0.0.0.0/8 127.0.0.0/8 255.0.0.0/8 551 */ 552 if (IN_MULTICAST(ntohl(in->s_addr))) 553 return (-1); 554 switch ((ntohl(in->s_addr) & 0xff000000) >> 24) { 555 case 0: case 127: case 255: 556 return (-1); 557 } 558 559 /* 560 * reject packets with private address range. 561 * (requirement from RFC3056 section 2 1st paragraph) 562 */ 563 if (isrfc1918addr(in)) 564 return (-1); 565 566 /* 567 * reject packets with broadcast 568 */ 569 CK_STAILQ_FOREACH(ia4, &V_in_ifaddrhead, ia_link) { 570 if ((ia4->ia_ifa.ifa_ifp->if_flags & IFF_BROADCAST) == 0) 571 continue; 572 if (in->s_addr == ia4->ia_broadaddr.sin_addr.s_addr) { 573 return (-1); 574 } 575 } 576 577 /* 578 * perform ingress filter 579 */ 580 if (sc && (STF2IFP(sc)->if_flags & IFF_LINK2) == 0 && inifp) { 581 struct nhop_object *nh; 582 583 NET_EPOCH_ASSERT(); 584 nh = fib4_lookup(sc->sc_fibnum, *in, 0, 0, 0); 585 if (nh == NULL) 586 return (-1); 587 588 if (nh->nh_ifp != inifp) 589 return (-1); 590 } 591 592 return (0); 593 } 594 595 static int 596 stf_checkaddr6(struct stf_softc *sc, struct in6_addr *in6, struct ifnet *inifp) 597 { 598 /* 599 * check 6to4 addresses 600 */ 601 if (IN6_IS_ADDR_6TO4(in6)) { 602 struct in_addr in4; 603 bcopy(GET_V4(in6), &in4, sizeof(in4)); 604 return (stf_checkaddr4(sc, &in4, inifp)); 605 } 606 607 /* 608 * reject anything that look suspicious. the test is implemented 609 * in ip6_input too, but we check here as well to 610 * (1) reject bad packets earlier, and 611 * (2) to be safe against future ip6_input change. 612 */ 613 if (IN6_IS_ADDR_V4COMPAT(in6) || IN6_IS_ADDR_V4MAPPED(in6)) 614 return (-1); 615 616 return (0); 617 } 618 619 static int 620 in_stf_input(struct mbuf *m, int off, int proto, void *arg) 621 { 622 struct stf_softc *sc = arg; 623 struct ip *ip; 624 struct ip6_hdr *ip6; 625 u_int8_t otos, itos; 626 struct ifnet *ifp; 627 628 NET_EPOCH_ASSERT(); 629 630 if (proto != IPPROTO_IPV6) { 631 m_freem(m); 632 return (IPPROTO_DONE); 633 } 634 635 ip = mtod(m, struct ip *); 636 if (sc == NULL || (STF2IFP(sc)->if_flags & IFF_UP) == 0) { 637 m_freem(m); 638 return (IPPROTO_DONE); 639 } 640 641 ifp = STF2IFP(sc); 642 643 #ifdef MAC 644 mac_ifnet_create_mbuf(ifp, m); 645 #endif 646 647 /* 648 * perform sanity check against outer src/dst. 649 * for source, perform ingress filter as well. 650 */ 651 if (stf_checkaddr4(sc, &ip->ip_dst, NULL) < 0 || 652 stf_checkaddr4(sc, &ip->ip_src, m->m_pkthdr.rcvif) < 0) { 653 m_freem(m); 654 return (IPPROTO_DONE); 655 } 656 657 otos = ip->ip_tos; 658 m_adj(m, off); 659 660 if (m->m_len < sizeof(*ip6)) { 661 m = m_pullup(m, sizeof(*ip6)); 662 if (!m) 663 return (IPPROTO_DONE); 664 } 665 ip6 = mtod(m, struct ip6_hdr *); 666 667 /* 668 * perform sanity check against inner src/dst. 669 * for source, perform ingress filter as well. 670 */ 671 if (stf_checkaddr6(sc, &ip6->ip6_dst, NULL) < 0 || 672 stf_checkaddr6(sc, &ip6->ip6_src, m->m_pkthdr.rcvif) < 0) { 673 m_freem(m); 674 return (IPPROTO_DONE); 675 } 676 677 itos = IPV6_TRAFFIC_CLASS(ip6); 678 if ((ifp->if_flags & IFF_LINK1) != 0) 679 ip_ecn_egress(ECN_ALLOWED, &otos, &itos); 680 else 681 ip_ecn_egress(ECN_NOCARE, &otos, &itos); 682 ip6->ip6_flow &= ~htonl(0xff << 20); 683 ip6->ip6_flow |= htonl((u_int32_t)itos << 20); 684 685 m->m_pkthdr.rcvif = ifp; 686 687 if (bpf_peers_present(ifp->if_bpf)) { 688 /* 689 * We need to prepend the address family as 690 * a four byte field. Cons up a dummy header 691 * to pacify bpf. This is safe because bpf 692 * will only read from the mbuf (i.e., it won't 693 * try to free it or keep a pointer a to it). 694 */ 695 u_int32_t af = AF_INET6; 696 bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m); 697 } 698 699 /* 700 * Put the packet to the network layer input queue according to the 701 * specified address family. 702 * See net/if_gif.c for possible issues with packet processing 703 * reorder due to extra queueing. 704 */ 705 if_inc_counter(ifp, IFCOUNTER_IPACKETS, 1); 706 if_inc_counter(ifp, IFCOUNTER_IBYTES, m->m_pkthdr.len); 707 M_SETFIB(m, ifp->if_fib); 708 netisr_dispatch(NETISR_IPV6, m); 709 return (IPPROTO_DONE); 710 } 711 712 static int 713 stf_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data) 714 { 715 struct ifaddr *ifa; 716 struct ifreq *ifr; 717 struct sockaddr_in6 *sin6; 718 struct in_addr addr; 719 int error, mtu; 720 721 error = 0; 722 switch (cmd) { 723 case SIOCSIFADDR: 724 ifa = (struct ifaddr *)data; 725 if (ifa == NULL || ifa->ifa_addr->sa_family != AF_INET6) { 726 error = EAFNOSUPPORT; 727 break; 728 } 729 sin6 = (struct sockaddr_in6 *)ifa->ifa_addr; 730 if (!IN6_IS_ADDR_6TO4(&sin6->sin6_addr)) { 731 error = EINVAL; 732 break; 733 } 734 bcopy(GET_V4(&sin6->sin6_addr), &addr, sizeof(addr)); 735 if (isrfc1918addr(&addr)) { 736 error = EINVAL; 737 break; 738 } 739 740 ifp->if_flags |= IFF_UP; 741 ifp->if_drv_flags |= IFF_DRV_RUNNING; 742 break; 743 744 case SIOCADDMULTI: 745 case SIOCDELMULTI: 746 ifr = (struct ifreq *)data; 747 if (ifr && ifr->ifr_addr.sa_family == AF_INET6) 748 ; 749 else 750 error = EAFNOSUPPORT; 751 break; 752 753 case SIOCGIFMTU: 754 break; 755 756 case SIOCSIFMTU: 757 ifr = (struct ifreq *)data; 758 mtu = ifr->ifr_mtu; 759 /* RFC 4213 3.2 ideal world MTU */ 760 if (mtu < IPV6_MINMTU || mtu > IF_MAXMTU - 20) 761 return (EINVAL); 762 ifp->if_mtu = mtu; 763 break; 764 765 default: 766 error = EINVAL; 767 break; 768 } 769 770 return (error); 771 } 772