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/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, 0, "6to4 Interface"); 126 127 static int stf_permit_rfc1918 = 0; 128 SYSCTL_INT(_net_link_stf, OID_AUTO, permit_rfc1918, CTLFLAG_RWTUN, 129 &stf_permit_rfc1918, 0, "Permit the use of private IPv4 addresses"); 130 131 #define STFUNIT 0 132 133 #define IN6_IS_ADDR_6TO4(x) (ntohs((x)->s6_addr16[0]) == 0x2002) 134 135 /* 136 * XXX: Return a pointer with 16-bit aligned. Don't cast it to 137 * struct in_addr *; use bcopy() instead. 138 */ 139 #define GET_V4(x) (&(x)->s6_addr16[1]) 140 141 struct stf_softc { 142 struct ifnet *sc_ifp; 143 u_int sc_fibnum; 144 const struct encaptab *encap_cookie; 145 }; 146 #define STF2IFP(sc) ((sc)->sc_ifp) 147 148 static const char stfname[] = "stf"; 149 150 static MALLOC_DEFINE(M_STF, stfname, "6to4 Tunnel Interface"); 151 static const int ip_stf_ttl = 40; 152 153 static int in_stf_input(struct mbuf *, int, int, void *); 154 static char *stfnames[] = {"stf0", "stf", "6to4", NULL}; 155 156 static int stfmodevent(module_t, int, void *); 157 static int stf_encapcheck(const struct mbuf *, int, int, void *); 158 static int stf_getsrcifa6(struct ifnet *, struct in6_addr *, struct in6_addr *); 159 static int stf_output(struct ifnet *, struct mbuf *, const struct sockaddr *, 160 struct route *); 161 static int isrfc1918addr(struct in_addr *); 162 static int stf_checkaddr4(struct stf_softc *, struct in_addr *, 163 struct ifnet *); 164 static int stf_checkaddr6(struct stf_softc *, struct in6_addr *, 165 struct ifnet *); 166 static int stf_ioctl(struct ifnet *, u_long, caddr_t); 167 168 static int stf_clone_match(struct if_clone *, const char *); 169 static int stf_clone_create(struct if_clone *, char *, size_t, caddr_t); 170 static int stf_clone_destroy(struct if_clone *, struct ifnet *); 171 static struct if_clone *stf_cloner; 172 173 static const struct encap_config ipv4_encap_cfg = { 174 .proto = IPPROTO_IPV6, 175 .min_length = sizeof(struct ip), 176 .exact_match = (sizeof(in_addr_t) << 3) + 8, 177 .check = stf_encapcheck, 178 .input = in_stf_input 179 }; 180 181 static int 182 stf_clone_match(struct if_clone *ifc, const char *name) 183 { 184 int i; 185 186 for(i = 0; stfnames[i] != NULL; i++) { 187 if (strcmp(stfnames[i], name) == 0) 188 return (1); 189 } 190 191 return (0); 192 } 193 194 static int 195 stf_clone_create(struct if_clone *ifc, char *name, size_t len, caddr_t params) 196 { 197 char *dp; 198 int err, unit, wildcard; 199 struct stf_softc *sc; 200 struct ifnet *ifp; 201 202 err = ifc_name2unit(name, &unit); 203 if (err != 0) 204 return (err); 205 wildcard = (unit < 0); 206 207 /* 208 * We can only have one unit, but since unit allocation is 209 * already locked, we use it to keep from allocating extra 210 * interfaces. 211 */ 212 unit = STFUNIT; 213 err = ifc_alloc_unit(ifc, &unit); 214 if (err != 0) 215 return (err); 216 217 sc = malloc(sizeof(struct stf_softc), M_STF, M_WAITOK | M_ZERO); 218 ifp = STF2IFP(sc) = if_alloc(IFT_STF); 219 if (ifp == NULL) { 220 free(sc, M_STF); 221 ifc_free_unit(ifc, unit); 222 return (ENOSPC); 223 } 224 ifp->if_softc = sc; 225 sc->sc_fibnum = curthread->td_proc->p_fibnum; 226 227 /* 228 * Set the name manually rather then using if_initname because 229 * we don't conform to the default naming convention for interfaces. 230 * In the wildcard case, we need to update the name. 231 */ 232 if (wildcard) { 233 for (dp = name; *dp != '\0'; dp++); 234 if (snprintf(dp, len - (dp-name), "%d", unit) > 235 len - (dp-name) - 1) { 236 /* 237 * This can only be a programmer error and 238 * there's no straightforward way to recover if 239 * it happens. 240 */ 241 panic("if_clone_create(): interface name too long"); 242 } 243 } 244 strlcpy(ifp->if_xname, name, IFNAMSIZ); 245 ifp->if_dname = stfname; 246 ifp->if_dunit = IF_DUNIT_NONE; 247 248 sc->encap_cookie = ip_encap_attach(&ipv4_encap_cfg, sc, M_WAITOK); 249 if (sc->encap_cookie == NULL) { 250 if_printf(ifp, "attach failed\n"); 251 free(sc, M_STF); 252 ifc_free_unit(ifc, unit); 253 return (ENOMEM); 254 } 255 256 ifp->if_mtu = IPV6_MMTU; 257 ifp->if_ioctl = stf_ioctl; 258 ifp->if_output = stf_output; 259 ifp->if_snd.ifq_maxlen = ifqmaxlen; 260 if_attach(ifp); 261 bpfattach(ifp, DLT_NULL, sizeof(u_int32_t)); 262 return (0); 263 } 264 265 static int 266 stf_clone_destroy(struct if_clone *ifc, struct ifnet *ifp) 267 { 268 struct stf_softc *sc = ifp->if_softc; 269 int err __unused; 270 271 err = ip_encap_detach(sc->encap_cookie); 272 KASSERT(err == 0, ("Unexpected error detaching encap_cookie")); 273 bpfdetach(ifp); 274 if_detach(ifp); 275 if_free(ifp); 276 277 free(sc, M_STF); 278 ifc_free_unit(ifc, STFUNIT); 279 280 return (0); 281 } 282 283 static int 284 stfmodevent(module_t mod, int type, void *data) 285 { 286 287 switch (type) { 288 case MOD_LOAD: 289 stf_cloner = if_clone_advanced(stfname, 0, stf_clone_match, 290 stf_clone_create, stf_clone_destroy); 291 break; 292 case MOD_UNLOAD: 293 if_clone_detach(stf_cloner); 294 break; 295 default: 296 return (EOPNOTSUPP); 297 } 298 299 return (0); 300 } 301 302 static moduledata_t stf_mod = { 303 "if_stf", 304 stfmodevent, 305 0 306 }; 307 308 DECLARE_MODULE(if_stf, stf_mod, SI_SUB_PSEUDO, SI_ORDER_ANY); 309 310 static int 311 stf_encapcheck(const struct mbuf *m, int off, int proto, void *arg) 312 { 313 struct ip ip; 314 struct stf_softc *sc; 315 struct in_addr a, b, mask; 316 struct in6_addr addr6, mask6; 317 318 sc = (struct stf_softc *)arg; 319 if (sc == NULL) 320 return 0; 321 322 if ((STF2IFP(sc)->if_flags & IFF_UP) == 0) 323 return 0; 324 325 /* IFF_LINK0 means "no decapsulation" */ 326 if ((STF2IFP(sc)->if_flags & IFF_LINK0) != 0) 327 return 0; 328 329 if (proto != IPPROTO_IPV6) 330 return 0; 331 332 m_copydata(m, 0, sizeof(ip), (caddr_t)&ip); 333 334 if (ip.ip_v != 4) 335 return 0; 336 337 if (stf_getsrcifa6(STF2IFP(sc), &addr6, &mask6) != 0) 338 return (0); 339 340 /* 341 * check if IPv4 dst matches the IPv4 address derived from the 342 * local 6to4 address. 343 * success on: dst = 10.1.1.1, ia6->ia_addr = 2002:0a01:0101:... 344 */ 345 if (bcmp(GET_V4(&addr6), &ip.ip_dst, sizeof(ip.ip_dst)) != 0) 346 return 0; 347 348 /* 349 * check if IPv4 src matches the IPv4 address derived from the 350 * local 6to4 address masked by prefixmask. 351 * success on: src = 10.1.1.1, ia6->ia_addr = 2002:0a00:.../24 352 * fail on: src = 10.1.1.1, ia6->ia_addr = 2002:0b00:.../24 353 */ 354 bzero(&a, sizeof(a)); 355 bcopy(GET_V4(&addr6), &a, sizeof(a)); 356 bcopy(GET_V4(&mask6), &mask, sizeof(mask)); 357 a.s_addr &= mask.s_addr; 358 b = ip.ip_src; 359 b.s_addr &= mask.s_addr; 360 if (a.s_addr != b.s_addr) 361 return 0; 362 363 /* stf interface makes single side match only */ 364 return 32; 365 } 366 367 static int 368 stf_getsrcifa6(struct ifnet *ifp, struct in6_addr *addr, struct in6_addr *mask) 369 { 370 struct rm_priotracker in_ifa_tracker; 371 struct ifaddr *ia; 372 struct in_ifaddr *ia4; 373 struct in6_ifaddr *ia6; 374 struct sockaddr_in6 *sin6; 375 struct in_addr in; 376 377 if_addr_rlock(ifp); 378 CK_STAILQ_FOREACH(ia, &ifp->if_addrhead, ifa_link) { 379 if (ia->ifa_addr->sa_family != AF_INET6) 380 continue; 381 sin6 = (struct sockaddr_in6 *)ia->ifa_addr; 382 if (!IN6_IS_ADDR_6TO4(&sin6->sin6_addr)) 383 continue; 384 385 bcopy(GET_V4(&sin6->sin6_addr), &in, sizeof(in)); 386 IN_IFADDR_RLOCK(&in_ifa_tracker); 387 LIST_FOREACH(ia4, INADDR_HASH(in.s_addr), ia_hash) 388 if (ia4->ia_addr.sin_addr.s_addr == in.s_addr) 389 break; 390 IN_IFADDR_RUNLOCK(&in_ifa_tracker); 391 if (ia4 == NULL) 392 continue; 393 394 ia6 = (struct in6_ifaddr *)ia; 395 396 *addr = sin6->sin6_addr; 397 *mask = ia6->ia_prefixmask.sin6_addr; 398 if_addr_runlock(ifp); 399 return (0); 400 } 401 if_addr_runlock(ifp); 402 403 return (ENOENT); 404 } 405 406 static int 407 stf_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst, 408 struct route *ro) 409 { 410 struct stf_softc *sc; 411 const struct sockaddr_in6 *dst6; 412 struct in_addr in4; 413 const void *ptr; 414 u_int8_t tos; 415 struct ip *ip; 416 struct ip6_hdr *ip6; 417 struct in6_addr addr6, mask6; 418 int error; 419 420 #ifdef MAC 421 error = mac_ifnet_check_transmit(ifp, m); 422 if (error) { 423 m_freem(m); 424 return (error); 425 } 426 #endif 427 428 sc = ifp->if_softc; 429 dst6 = (const struct sockaddr_in6 *)dst; 430 431 /* just in case */ 432 if ((ifp->if_flags & IFF_UP) == 0) { 433 m_freem(m); 434 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 435 return ENETDOWN; 436 } 437 438 /* 439 * If we don't have an ip4 address that match my inner ip6 address, 440 * we shouldn't generate output. Without this check, we'll end up 441 * using wrong IPv4 source. 442 */ 443 if (stf_getsrcifa6(ifp, &addr6, &mask6) != 0) { 444 m_freem(m); 445 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 446 return ENETDOWN; 447 } 448 449 if (m->m_len < sizeof(*ip6)) { 450 m = m_pullup(m, sizeof(*ip6)); 451 if (!m) { 452 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 453 return ENOBUFS; 454 } 455 } 456 ip6 = mtod(m, struct ip6_hdr *); 457 tos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; 458 459 /* 460 * Pickup the right outer dst addr from the list of candidates. 461 * ip6_dst has priority as it may be able to give us shorter IPv4 hops. 462 */ 463 ptr = NULL; 464 if (IN6_IS_ADDR_6TO4(&ip6->ip6_dst)) 465 ptr = GET_V4(&ip6->ip6_dst); 466 else if (IN6_IS_ADDR_6TO4(&dst6->sin6_addr)) 467 ptr = GET_V4(&dst6->sin6_addr); 468 else { 469 m_freem(m); 470 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 471 return ENETUNREACH; 472 } 473 bcopy(ptr, &in4, sizeof(in4)); 474 475 if (bpf_peers_present(ifp->if_bpf)) { 476 /* 477 * We need to prepend the address family as 478 * a four byte field. Cons up a dummy header 479 * to pacify bpf. This is safe because bpf 480 * will only read from the mbuf (i.e., it won't 481 * try to free it or keep a pointer a to it). 482 */ 483 u_int af = AF_INET6; 484 bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m); 485 } 486 487 M_PREPEND(m, sizeof(struct ip), M_NOWAIT); 488 if (m == NULL) { 489 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 490 return ENOBUFS; 491 } 492 ip = mtod(m, struct ip *); 493 494 bzero(ip, sizeof(*ip)); 495 496 bcopy(GET_V4(&addr6), &ip->ip_src, sizeof(ip->ip_src)); 497 bcopy(&in4, &ip->ip_dst, sizeof(ip->ip_dst)); 498 ip->ip_p = IPPROTO_IPV6; 499 ip->ip_ttl = ip_stf_ttl; 500 ip->ip_len = htons(m->m_pkthdr.len); 501 if (ifp->if_flags & IFF_LINK1) 502 ip_ecn_ingress(ECN_ALLOWED, &ip->ip_tos, &tos); 503 else 504 ip_ecn_ingress(ECN_NOCARE, &ip->ip_tos, &tos); 505 506 M_SETFIB(m, sc->sc_fibnum); 507 if_inc_counter(ifp, IFCOUNTER_OPACKETS, 1); 508 error = ip_output(m, NULL, NULL, 0, NULL, NULL); 509 510 return error; 511 } 512 513 static int 514 isrfc1918addr(struct in_addr *in) 515 { 516 /* 517 * returns 1 if private address range: 518 * 10.0.0.0/8 172.16.0.0/12 192.168.0.0/16 519 */ 520 if (stf_permit_rfc1918 == 0 && ( 521 (ntohl(in->s_addr) & 0xff000000) >> 24 == 10 || 522 (ntohl(in->s_addr) & 0xfff00000) >> 16 == 172 * 256 + 16 || 523 (ntohl(in->s_addr) & 0xffff0000) >> 16 == 192 * 256 + 168)) 524 return 1; 525 526 return 0; 527 } 528 529 static int 530 stf_checkaddr4(struct stf_softc *sc, struct in_addr *in, struct ifnet *inifp) 531 { 532 struct rm_priotracker in_ifa_tracker; 533 struct in_ifaddr *ia4; 534 535 /* 536 * reject packets with the following address: 537 * 224.0.0.0/4 0.0.0.0/8 127.0.0.0/8 255.0.0.0/8 538 */ 539 if (IN_MULTICAST(ntohl(in->s_addr))) 540 return -1; 541 switch ((ntohl(in->s_addr) & 0xff000000) >> 24) { 542 case 0: case 127: case 255: 543 return -1; 544 } 545 546 /* 547 * reject packets with private address range. 548 * (requirement from RFC3056 section 2 1st paragraph) 549 */ 550 if (isrfc1918addr(in)) 551 return -1; 552 553 /* 554 * reject packets with broadcast 555 */ 556 IN_IFADDR_RLOCK(&in_ifa_tracker); 557 CK_STAILQ_FOREACH(ia4, &V_in_ifaddrhead, ia_link) { 558 if ((ia4->ia_ifa.ifa_ifp->if_flags & IFF_BROADCAST) == 0) 559 continue; 560 if (in->s_addr == ia4->ia_broadaddr.sin_addr.s_addr) { 561 IN_IFADDR_RUNLOCK(&in_ifa_tracker); 562 return -1; 563 } 564 } 565 IN_IFADDR_RUNLOCK(&in_ifa_tracker); 566 567 /* 568 * perform ingress filter 569 */ 570 if (sc && (STF2IFP(sc)->if_flags & IFF_LINK2) == 0 && inifp) { 571 struct nhop4_basic nh4; 572 573 if (fib4_lookup_nh_basic(sc->sc_fibnum, *in, 0, 0, &nh4) != 0) 574 return (-1); 575 576 if (nh4.nh_ifp != inifp) 577 return (-1); 578 } 579 580 return 0; 581 } 582 583 static int 584 stf_checkaddr6(struct stf_softc *sc, struct in6_addr *in6, struct ifnet *inifp) 585 { 586 /* 587 * check 6to4 addresses 588 */ 589 if (IN6_IS_ADDR_6TO4(in6)) { 590 struct in_addr in4; 591 bcopy(GET_V4(in6), &in4, sizeof(in4)); 592 return stf_checkaddr4(sc, &in4, inifp); 593 } 594 595 /* 596 * reject anything that look suspicious. the test is implemented 597 * in ip6_input too, but we check here as well to 598 * (1) reject bad packets earlier, and 599 * (2) to be safe against future ip6_input change. 600 */ 601 if (IN6_IS_ADDR_V4COMPAT(in6) || IN6_IS_ADDR_V4MAPPED(in6)) 602 return -1; 603 604 return 0; 605 } 606 607 static int 608 in_stf_input(struct mbuf *m, int off, int proto, void *arg) 609 { 610 struct stf_softc *sc = arg; 611 struct ip *ip; 612 struct ip6_hdr *ip6; 613 u_int8_t otos, itos; 614 struct ifnet *ifp; 615 616 if (proto != IPPROTO_IPV6) { 617 m_freem(m); 618 return (IPPROTO_DONE); 619 } 620 621 ip = mtod(m, struct ip *); 622 if (sc == NULL || (STF2IFP(sc)->if_flags & IFF_UP) == 0) { 623 m_freem(m); 624 return (IPPROTO_DONE); 625 } 626 627 ifp = STF2IFP(sc); 628 629 #ifdef MAC 630 mac_ifnet_create_mbuf(ifp, m); 631 #endif 632 633 /* 634 * perform sanity check against outer src/dst. 635 * for source, perform ingress filter as well. 636 */ 637 if (stf_checkaddr4(sc, &ip->ip_dst, NULL) < 0 || 638 stf_checkaddr4(sc, &ip->ip_src, m->m_pkthdr.rcvif) < 0) { 639 m_freem(m); 640 return (IPPROTO_DONE); 641 } 642 643 otos = ip->ip_tos; 644 m_adj(m, off); 645 646 if (m->m_len < sizeof(*ip6)) { 647 m = m_pullup(m, sizeof(*ip6)); 648 if (!m) 649 return (IPPROTO_DONE); 650 } 651 ip6 = mtod(m, struct ip6_hdr *); 652 653 /* 654 * perform sanity check against inner src/dst. 655 * for source, perform ingress filter as well. 656 */ 657 if (stf_checkaddr6(sc, &ip6->ip6_dst, NULL) < 0 || 658 stf_checkaddr6(sc, &ip6->ip6_src, m->m_pkthdr.rcvif) < 0) { 659 m_freem(m); 660 return (IPPROTO_DONE); 661 } 662 663 itos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; 664 if ((ifp->if_flags & IFF_LINK1) != 0) 665 ip_ecn_egress(ECN_ALLOWED, &otos, &itos); 666 else 667 ip_ecn_egress(ECN_NOCARE, &otos, &itos); 668 ip6->ip6_flow &= ~htonl(0xff << 20); 669 ip6->ip6_flow |= htonl((u_int32_t)itos << 20); 670 671 m->m_pkthdr.rcvif = ifp; 672 673 if (bpf_peers_present(ifp->if_bpf)) { 674 /* 675 * We need to prepend the address family as 676 * a four byte field. Cons up a dummy header 677 * to pacify bpf. This is safe because bpf 678 * will only read from the mbuf (i.e., it won't 679 * try to free it or keep a pointer a to it). 680 */ 681 u_int32_t af = AF_INET6; 682 bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m); 683 } 684 685 /* 686 * Put the packet to the network layer input queue according to the 687 * specified address family. 688 * See net/if_gif.c for possible issues with packet processing 689 * reorder due to extra queueing. 690 */ 691 if_inc_counter(ifp, IFCOUNTER_IPACKETS, 1); 692 if_inc_counter(ifp, IFCOUNTER_IBYTES, m->m_pkthdr.len); 693 M_SETFIB(m, ifp->if_fib); 694 netisr_dispatch(NETISR_IPV6, m); 695 return (IPPROTO_DONE); 696 } 697 698 static int 699 stf_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data) 700 { 701 struct ifaddr *ifa; 702 struct ifreq *ifr; 703 struct sockaddr_in6 *sin6; 704 struct in_addr addr; 705 int error, mtu; 706 707 error = 0; 708 switch (cmd) { 709 case SIOCSIFADDR: 710 ifa = (struct ifaddr *)data; 711 if (ifa == NULL || ifa->ifa_addr->sa_family != AF_INET6) { 712 error = EAFNOSUPPORT; 713 break; 714 } 715 sin6 = (struct sockaddr_in6 *)ifa->ifa_addr; 716 if (!IN6_IS_ADDR_6TO4(&sin6->sin6_addr)) { 717 error = EINVAL; 718 break; 719 } 720 bcopy(GET_V4(&sin6->sin6_addr), &addr, sizeof(addr)); 721 if (isrfc1918addr(&addr)) { 722 error = EINVAL; 723 break; 724 } 725 726 ifp->if_flags |= IFF_UP; 727 break; 728 729 case SIOCADDMULTI: 730 case SIOCDELMULTI: 731 ifr = (struct ifreq *)data; 732 if (ifr && ifr->ifr_addr.sa_family == AF_INET6) 733 ; 734 else 735 error = EAFNOSUPPORT; 736 break; 737 738 case SIOCGIFMTU: 739 break; 740 741 case SIOCSIFMTU: 742 ifr = (struct ifreq *)data; 743 mtu = ifr->ifr_mtu; 744 /* RFC 4213 3.2 ideal world MTU */ 745 if (mtu < IPV6_MINMTU || mtu > IF_MAXMTU - 20) 746 return (EINVAL); 747 ifp->if_mtu = mtu; 748 break; 749 750 default: 751 error = EINVAL; 752 break; 753 } 754 755 return error; 756 } 757