1 /* $FreeBSD$ */ 2 /* $KAME: if_stf.c,v 1.73 2001/12/03 11:08:30 keiichi Exp $ */ 3 4 /* 5 * Copyright (C) 2000 WIDE Project. 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the project nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33 /* 34 * 6to4 interface, based on RFC3056. 35 * 36 * 6to4 interface is NOT capable of link-layer (I mean, IPv4) multicasting. 37 * There is no address mapping defined from IPv6 multicast address to IPv4 38 * address. Therefore, we do not have IFF_MULTICAST on the interface. 39 * 40 * Due to the lack of address mapping for link-local addresses, we cannot 41 * throw packets toward link-local addresses (fe80::x). Also, we cannot throw 42 * packets to link-local multicast addresses (ff02::x). 43 * 44 * Here are interesting symptoms due to the lack of link-local address: 45 * 46 * Unicast routing exchange: 47 * - RIPng: Impossible. Uses link-local multicast packet toward ff02::9, 48 * and link-local addresses as nexthop. 49 * - OSPFv6: Impossible. OSPFv6 assumes that there's link-local address 50 * assigned to the link, and makes use of them. Also, HELLO packets use 51 * link-local multicast addresses (ff02::5 and ff02::6). 52 * - BGP4+: Maybe. You can only use global address as nexthop, and global 53 * address as TCP endpoint address. 54 * 55 * Multicast routing protocols: 56 * - PIM: Hello packet cannot be used to discover adjacent PIM routers. 57 * Adjacent PIM routers must be configured manually (is it really spec-wise 58 * correct thing to do?). 59 * 60 * ICMPv6: 61 * - Redirects cannot be used due to the lack of link-local address. 62 * 63 * stf interface does not have, and will not need, a link-local address. 64 * It seems to have no real benefit and does not help the above symptoms much. 65 * Even if we assign link-locals to interface, we cannot really 66 * use link-local unicast/multicast on top of 6to4 cloud (since there's no 67 * encapsulation defined for link-local address), and the above analysis does 68 * not change. RFC3056 does not mandate the assignment of link-local address 69 * either. 70 * 71 * 6to4 interface has security issues. Refer to 72 * http://playground.iijlab.net/i-d/draft-itojun-ipv6-transition-abuse-00.txt 73 * for details. The code tries to filter out some of malicious packets. 74 * Note that there is no way to be 100% secure. 75 */ 76 77 #include "opt_inet.h" 78 #include "opt_inet6.h" 79 #include "opt_mac.h" 80 81 #include <sys/param.h> 82 #include <sys/systm.h> 83 #include <sys/socket.h> 84 #include <sys/sockio.h> 85 #include <sys/mac.h> 86 #include <sys/mbuf.h> 87 #include <sys/errno.h> 88 #include <sys/kernel.h> 89 #include <sys/protosw.h> 90 #include <sys/queue.h> 91 #include <machine/cpu.h> 92 93 #include <sys/malloc.h> 94 95 #include <net/if.h> 96 #include <net/route.h> 97 #include <net/netisr.h> 98 #include <net/if_types.h> 99 #include <net/if_stf.h> 100 101 #include <netinet/in.h> 102 #include <netinet/in_systm.h> 103 #include <netinet/ip.h> 104 #include <netinet/ip_var.h> 105 #include <netinet/in_var.h> 106 107 #include <netinet/ip6.h> 108 #include <netinet6/ip6_var.h> 109 #include <netinet6/in6_var.h> 110 #include <netinet/ip_ecn.h> 111 112 #include <netinet/ip_encap.h> 113 114 #include <machine/stdarg.h> 115 116 #include <net/net_osdep.h> 117 118 #include <net/bpf.h> 119 120 #define STFNAME "stf" 121 122 #define IN6_IS_ADDR_6TO4(x) (ntohs((x)->s6_addr16[0]) == 0x2002) 123 124 /* 125 * XXX: Return a pointer with 16-bit aligned. Don't cast it to 126 * struct in_addr *; use bcopy() instead. 127 */ 128 #define GET_V4(x) ((caddr_t)(&(x)->s6_addr16[1])) 129 130 struct stf_softc { 131 struct ifnet sc_if; /* common area */ 132 union { 133 struct route __sc_ro4; 134 struct route_in6 __sc_ro6; /* just for safety */ 135 } __sc_ro46; 136 #define sc_ro __sc_ro46.__sc_ro4 137 const struct encaptab *encap_cookie; 138 LIST_ENTRY(stf_softc) sc_list; /* all stf's are linked */ 139 }; 140 141 static LIST_HEAD(, stf_softc) stf_softc_list; 142 143 static MALLOC_DEFINE(M_STF, STFNAME, "6to4 Tunnel Interface"); 144 static int ip_stf_ttl = 40; 145 146 extern struct domain inetdomain; 147 struct protosw in_stf_protosw = 148 { SOCK_RAW, &inetdomain, IPPROTO_IPV6, PR_ATOMIC|PR_ADDR, 149 in_stf_input, (pr_output_t*)rip_output, 0, rip_ctloutput, 150 0, 151 0, 0, 0, 0, 152 &rip_usrreqs 153 }; 154 155 static int stfmodevent(module_t, int, void *); 156 static int stf_encapcheck(const struct mbuf *, int, int, void *); 157 static struct in6_ifaddr *stf_getsrcifa6(struct ifnet *); 158 static int stf_output(struct ifnet *, struct mbuf *, struct sockaddr *, 159 struct rtentry *); 160 static int isrfc1918addr(struct in_addr *); 161 static int stf_checkaddr4(struct stf_softc *, struct in_addr *, 162 struct ifnet *); 163 static int stf_checkaddr6(struct stf_softc *, struct in6_addr *, 164 struct ifnet *); 165 static void stf_rtrequest(int, struct rtentry *, struct rt_addrinfo *); 166 static int stf_ioctl(struct ifnet *, u_long, caddr_t); 167 168 int stf_clone_create(struct if_clone *, int); 169 void stf_clone_destroy(struct ifnet *); 170 171 /* only one clone is currently allowed */ 172 struct if_clone stf_cloner = 173 IF_CLONE_INITIALIZER(STFNAME, stf_clone_create, stf_clone_destroy, 0, 0); 174 175 int 176 stf_clone_create(ifc, unit) 177 struct if_clone *ifc; 178 int unit; 179 { 180 struct stf_softc *sc; 181 182 sc = malloc(sizeof(struct stf_softc), M_STF, M_WAITOK | M_ZERO); 183 sc->sc_if.if_name = STFNAME; 184 sc->sc_if.if_unit = unit; 185 186 sc->encap_cookie = encap_attach_func(AF_INET, IPPROTO_IPV6, 187 stf_encapcheck, &in_stf_protosw, sc); 188 if (sc->encap_cookie == NULL) { 189 printf("%s: attach failed\n", if_name(&sc->sc_if)); 190 free(sc, M_STF); 191 return (ENOMEM); 192 } 193 194 sc->sc_if.if_mtu = IPV6_MMTU; 195 sc->sc_if.if_ioctl = stf_ioctl; 196 sc->sc_if.if_output = stf_output; 197 sc->sc_if.if_type = IFT_STF; 198 sc->sc_if.if_snd.ifq_maxlen = IFQ_MAXLEN; 199 if_attach(&sc->sc_if); 200 bpfattach(&sc->sc_if, DLT_NULL, sizeof(u_int)); 201 LIST_INSERT_HEAD(&stf_softc_list, sc, sc_list); 202 return (0); 203 } 204 205 void 206 stf_clone_destroy(ifp) 207 struct ifnet *ifp; 208 { 209 int err; 210 struct stf_softc *sc = (void *) ifp; 211 212 LIST_REMOVE(sc, sc_list); 213 err = encap_detach(sc->encap_cookie); 214 KASSERT(err == 0, ("Unexpected error detaching encap_cookie")); 215 bpfdetach(ifp); 216 if_detach(ifp); 217 218 free(sc, M_STF); 219 } 220 221 static int 222 stfmodevent(mod, type, data) 223 module_t mod; 224 int type; 225 void *data; 226 { 227 228 switch (type) { 229 case MOD_LOAD: 230 LIST_INIT(&stf_softc_list); 231 if_clone_attach(&stf_cloner); 232 233 break; 234 case MOD_UNLOAD: 235 if_clone_detach(&stf_cloner); 236 237 while (!LIST_EMPTY(&stf_softc_list)) 238 stf_clone_destroy(&LIST_FIRST(&stf_softc_list)->sc_if); 239 break; 240 } 241 242 return (0); 243 } 244 245 static moduledata_t stf_mod = { 246 "if_stf", 247 stfmodevent, 248 0 249 }; 250 251 DECLARE_MODULE(if_stf, stf_mod, SI_SUB_PSEUDO, SI_ORDER_ANY); 252 253 static int 254 stf_encapcheck(m, off, proto, arg) 255 const struct mbuf *m; 256 int off; 257 int proto; 258 void *arg; 259 { 260 struct ip ip; 261 struct in6_ifaddr *ia6; 262 struct stf_softc *sc; 263 struct in_addr a, b, mask; 264 265 sc = (struct stf_softc *)arg; 266 if (sc == NULL) 267 return 0; 268 269 if ((sc->sc_if.if_flags & IFF_UP) == 0) 270 return 0; 271 272 /* IFF_LINK0 means "no decapsulation" */ 273 if ((sc->sc_if.if_flags & IFF_LINK0) != 0) 274 return 0; 275 276 if (proto != IPPROTO_IPV6) 277 return 0; 278 279 /* LINTED const cast */ 280 m_copydata((struct mbuf *)(uintptr_t)m, 0, sizeof(ip), (caddr_t)&ip); 281 282 if (ip.ip_v != 4) 283 return 0; 284 285 ia6 = stf_getsrcifa6(&sc->sc_if); 286 if (ia6 == NULL) 287 return 0; 288 289 /* 290 * check if IPv4 dst matches the IPv4 address derived from the 291 * local 6to4 address. 292 * success on: dst = 10.1.1.1, ia6->ia_addr = 2002:0a01:0101:... 293 */ 294 if (bcmp(GET_V4(&ia6->ia_addr.sin6_addr), &ip.ip_dst, 295 sizeof(ip.ip_dst)) != 0) 296 return 0; 297 298 /* 299 * check if IPv4 src matches the IPv4 address derived from the 300 * local 6to4 address masked by prefixmask. 301 * success on: src = 10.1.1.1, ia6->ia_addr = 2002:0a00:.../24 302 * fail on: src = 10.1.1.1, ia6->ia_addr = 2002:0b00:.../24 303 */ 304 bzero(&a, sizeof(a)); 305 bcopy(GET_V4(&ia6->ia_addr.sin6_addr), &a, sizeof(a)); 306 bcopy(GET_V4(&ia6->ia_prefixmask.sin6_addr), &mask, sizeof(mask)); 307 a.s_addr &= mask.s_addr; 308 b = ip.ip_src; 309 b.s_addr &= mask.s_addr; 310 if (a.s_addr != b.s_addr) 311 return 0; 312 313 /* stf interface makes single side match only */ 314 return 32; 315 } 316 317 static struct in6_ifaddr * 318 stf_getsrcifa6(ifp) 319 struct ifnet *ifp; 320 { 321 struct ifaddr *ia; 322 struct in_ifaddr *ia4; 323 struct sockaddr_in6 *sin6; 324 struct in_addr in; 325 326 for (ia = TAILQ_FIRST(&ifp->if_addrlist); 327 ia; 328 ia = TAILQ_NEXT(ia, ifa_list)) 329 { 330 if (ia->ifa_addr == NULL) 331 continue; 332 if (ia->ifa_addr->sa_family != AF_INET6) 333 continue; 334 sin6 = (struct sockaddr_in6 *)ia->ifa_addr; 335 if (!IN6_IS_ADDR_6TO4(&sin6->sin6_addr)) 336 continue; 337 338 bcopy(GET_V4(&sin6->sin6_addr), &in, sizeof(in)); 339 LIST_FOREACH(ia4, INADDR_HASH(in.s_addr), ia_hash) 340 if (ia4->ia_addr.sin_addr.s_addr == in.s_addr) 341 break; 342 if (ia4 == NULL) 343 continue; 344 345 return (struct in6_ifaddr *)ia; 346 } 347 348 return NULL; 349 } 350 351 static int 352 stf_output(ifp, m, dst, rt) 353 struct ifnet *ifp; 354 struct mbuf *m; 355 struct sockaddr *dst; 356 struct rtentry *rt; 357 { 358 struct stf_softc *sc; 359 struct sockaddr_in6 *dst6; 360 struct in_addr in4; 361 caddr_t ptr; 362 struct sockaddr_in *dst4; 363 u_int8_t tos; 364 struct ip *ip; 365 struct ip6_hdr *ip6; 366 struct in6_ifaddr *ia6; 367 #ifdef MAC 368 int error; 369 370 error = mac_check_ifnet_transmit(ifp, m); 371 if (error) { 372 m_freem(m); 373 return (error); 374 } 375 #endif 376 377 sc = (struct stf_softc*)ifp; 378 dst6 = (struct sockaddr_in6 *)dst; 379 380 /* just in case */ 381 if ((ifp->if_flags & IFF_UP) == 0) { 382 m_freem(m); 383 ifp->if_oerrors++; 384 return ENETDOWN; 385 } 386 387 /* 388 * If we don't have an ip4 address that match my inner ip6 address, 389 * we shouldn't generate output. Without this check, we'll end up 390 * using wrong IPv4 source. 391 */ 392 ia6 = stf_getsrcifa6(ifp); 393 if (ia6 == NULL) { 394 m_freem(m); 395 ifp->if_oerrors++; 396 return ENETDOWN; 397 } 398 399 if (m->m_len < sizeof(*ip6)) { 400 m = m_pullup(m, sizeof(*ip6)); 401 if (!m) { 402 ifp->if_oerrors++; 403 return ENOBUFS; 404 } 405 } 406 ip6 = mtod(m, struct ip6_hdr *); 407 tos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; 408 409 /* 410 * Pickup the right outer dst addr from the list of candidates. 411 * ip6_dst has priority as it may be able to give us shorter IPv4 hops. 412 */ 413 ptr = NULL; 414 if (IN6_IS_ADDR_6TO4(&ip6->ip6_dst)) 415 ptr = GET_V4(&ip6->ip6_dst); 416 else if (IN6_IS_ADDR_6TO4(&dst6->sin6_addr)) 417 ptr = GET_V4(&dst6->sin6_addr); 418 else { 419 m_freem(m); 420 ifp->if_oerrors++; 421 return ENETUNREACH; 422 } 423 bcopy(ptr, &in4, sizeof(in4)); 424 425 #if NBPFILTER > 0 426 if (ifp->if_bpf) { 427 /* 428 * We need to prepend the address family as 429 * a four byte field. Cons up a dummy header 430 * to pacify bpf. This is safe because bpf 431 * will only read from the mbuf (i.e., it won't 432 * try to free it or keep a pointer a to it). 433 */ 434 struct mbuf m0; 435 u_int32_t af = AF_INET6; 436 437 m0.m_next = m; 438 m0.m_len = 4; 439 m0.m_data = (char *)⁡ 440 441 #ifdef HAVE_OLD_BPF 442 BPF_MTAP(ifp, &m0); 443 #else 444 bpf_mtap(ifp->if_bpf, &m0); 445 #endif 446 } 447 #endif /*NBPFILTER > 0*/ 448 449 M_PREPEND(m, sizeof(struct ip), M_DONTWAIT); 450 if (m && m->m_len < sizeof(struct ip)) 451 m = m_pullup(m, sizeof(struct ip)); 452 if (m == NULL) { 453 ifp->if_oerrors++; 454 return ENOBUFS; 455 } 456 ip = mtod(m, struct ip *); 457 458 bzero(ip, sizeof(*ip)); 459 460 bcopy(GET_V4(&((struct sockaddr_in6 *)&ia6->ia_addr)->sin6_addr), 461 &ip->ip_src, sizeof(ip->ip_src)); 462 bcopy(&in4, &ip->ip_dst, sizeof(ip->ip_dst)); 463 ip->ip_p = IPPROTO_IPV6; 464 ip->ip_ttl = ip_stf_ttl; 465 ip->ip_len = m->m_pkthdr.len; /*host order*/ 466 if (ifp->if_flags & IFF_LINK1) 467 ip_ecn_ingress(ECN_ALLOWED, &ip->ip_tos, &tos); 468 else 469 ip_ecn_ingress(ECN_NOCARE, &ip->ip_tos, &tos); 470 471 dst4 = (struct sockaddr_in *)&sc->sc_ro.ro_dst; 472 if (dst4->sin_family != AF_INET || 473 bcmp(&dst4->sin_addr, &ip->ip_dst, sizeof(ip->ip_dst)) != 0) { 474 /* cache route doesn't match */ 475 dst4->sin_family = AF_INET; 476 dst4->sin_len = sizeof(struct sockaddr_in); 477 bcopy(&ip->ip_dst, &dst4->sin_addr, sizeof(dst4->sin_addr)); 478 if (sc->sc_ro.ro_rt) { 479 RTFREE(sc->sc_ro.ro_rt); 480 sc->sc_ro.ro_rt = NULL; 481 } 482 } 483 484 if (sc->sc_ro.ro_rt == NULL) { 485 rtalloc(&sc->sc_ro); 486 if (sc->sc_ro.ro_rt == NULL) { 487 m_freem(m); 488 ifp->if_oerrors++; 489 return ENETUNREACH; 490 } 491 } 492 493 ifp->if_opackets++; 494 return ip_output(m, NULL, &sc->sc_ro, 0, NULL, NULL); 495 } 496 497 static int 498 isrfc1918addr(in) 499 struct in_addr *in; 500 { 501 /* 502 * returns 1 if private address range: 503 * 10.0.0.0/8 172.16.0.0/12 192.168.0.0/16 504 */ 505 if ((ntohl(in->s_addr) & 0xff000000) >> 24 == 10 || 506 (ntohl(in->s_addr) & 0xfff00000) >> 16 == 172 * 256 + 16 || 507 (ntohl(in->s_addr) & 0xffff0000) >> 16 == 192 * 256 + 168) 508 return 1; 509 510 return 0; 511 } 512 513 static int 514 stf_checkaddr4(sc, in, inifp) 515 struct stf_softc *sc; 516 struct in_addr *in; 517 struct ifnet *inifp; /* incoming interface */ 518 { 519 struct in_ifaddr *ia4; 520 521 /* 522 * reject packets with the following address: 523 * 224.0.0.0/4 0.0.0.0/8 127.0.0.0/8 255.0.0.0/8 524 */ 525 if (IN_MULTICAST(ntohl(in->s_addr))) 526 return -1; 527 switch ((ntohl(in->s_addr) & 0xff000000) >> 24) { 528 case 0: case 127: case 255: 529 return -1; 530 } 531 532 /* 533 * reject packets with private address range. 534 * (requirement from RFC3056 section 2 1st paragraph) 535 */ 536 if (isrfc1918addr(in)) 537 return -1; 538 539 /* 540 * reject packets with broadcast 541 */ 542 for (ia4 = TAILQ_FIRST(&in_ifaddrhead); 543 ia4; 544 ia4 = TAILQ_NEXT(ia4, ia_link)) 545 { 546 if ((ia4->ia_ifa.ifa_ifp->if_flags & IFF_BROADCAST) == 0) 547 continue; 548 if (in->s_addr == ia4->ia_broadaddr.sin_addr.s_addr) 549 return -1; 550 } 551 552 /* 553 * perform ingress filter 554 */ 555 if (sc && (sc->sc_if.if_flags & IFF_LINK2) == 0 && inifp) { 556 struct sockaddr_in sin; 557 struct rtentry *rt; 558 559 bzero(&sin, sizeof(sin)); 560 sin.sin_family = AF_INET; 561 sin.sin_len = sizeof(struct sockaddr_in); 562 sin.sin_addr = *in; 563 rt = rtalloc1((struct sockaddr *)&sin, 0, 0UL); 564 if (!rt || rt->rt_ifp != inifp) { 565 #if 0 566 log(LOG_WARNING, "%s: packet from 0x%x dropped " 567 "due to ingress filter\n", if_name(&sc->sc_if), 568 (u_int32_t)ntohl(sin.sin_addr.s_addr)); 569 #endif 570 if (rt) 571 rtfree(rt); 572 return -1; 573 } 574 rtfree(rt); 575 } 576 577 return 0; 578 } 579 580 static int 581 stf_checkaddr6(sc, in6, inifp) 582 struct stf_softc *sc; 583 struct in6_addr *in6; 584 struct ifnet *inifp; /* incoming interface */ 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 void 608 in_stf_input(m, off) 609 struct mbuf *m; 610 int off; 611 { 612 int proto; 613 struct stf_softc *sc; 614 struct ip *ip; 615 struct ip6_hdr *ip6; 616 u_int8_t otos, itos; 617 int len, isr; 618 struct ifqueue *ifq = NULL; 619 struct ifnet *ifp; 620 621 proto = mtod(m, struct ip *)->ip_p; 622 623 if (proto != IPPROTO_IPV6) { 624 m_freem(m); 625 return; 626 } 627 628 ip = mtod(m, struct ip *); 629 630 sc = (struct stf_softc *)encap_getarg(m); 631 632 if (sc == NULL || (sc->sc_if.if_flags & IFF_UP) == 0) { 633 m_freem(m); 634 return; 635 } 636 637 ifp = &sc->sc_if; 638 639 #ifdef MAC 640 mac_create_mbuf_from_ifnet(ifp, m); 641 #endif 642 643 /* 644 * perform sanity check against outer src/dst. 645 * for source, perform ingress filter as well. 646 */ 647 if (stf_checkaddr4(sc, &ip->ip_dst, NULL) < 0 || 648 stf_checkaddr4(sc, &ip->ip_src, m->m_pkthdr.rcvif) < 0) { 649 m_freem(m); 650 return; 651 } 652 653 otos = ip->ip_tos; 654 m_adj(m, off); 655 656 if (m->m_len < sizeof(*ip6)) { 657 m = m_pullup(m, sizeof(*ip6)); 658 if (!m) 659 return; 660 } 661 ip6 = mtod(m, struct ip6_hdr *); 662 663 /* 664 * perform sanity check against inner src/dst. 665 * for source, perform ingress filter as well. 666 */ 667 if (stf_checkaddr6(sc, &ip6->ip6_dst, NULL) < 0 || 668 stf_checkaddr6(sc, &ip6->ip6_src, m->m_pkthdr.rcvif) < 0) { 669 m_freem(m); 670 return; 671 } 672 673 itos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; 674 if ((ifp->if_flags & IFF_LINK1) != 0) 675 ip_ecn_egress(ECN_ALLOWED, &otos, &itos); 676 else 677 ip_ecn_egress(ECN_NOCARE, &otos, &itos); 678 ip6->ip6_flow &= ~htonl(0xff << 20); 679 ip6->ip6_flow |= htonl((u_int32_t)itos << 20); 680 681 m->m_pkthdr.rcvif = ifp; 682 683 if (ifp->if_bpf) { 684 /* 685 * We need to prepend the address family as 686 * a four byte field. Cons up a dummy header 687 * to pacify bpf. This is safe because bpf 688 * will only read from the mbuf (i.e., it won't 689 * try to free it or keep a pointer a to it). 690 */ 691 struct mbuf m0; 692 u_int32_t af = AF_INET6; 693 694 m0.m_next = m; 695 m0.m_len = 4; 696 m0.m_data = (char *)⁡ 697 698 #ifdef HAVE_OLD_BPF 699 BPF_MTAP(ifp, &m0); 700 #else 701 bpf_mtap(ifp->if_bpf, &m0); 702 #endif 703 } 704 705 /* 706 * Put the packet to the network layer input queue according to the 707 * specified address family. 708 * See net/if_gif.c for possible issues with packet processing 709 * reorder due to extra queueing. 710 */ 711 ifq = &ip6intrq; 712 isr = NETISR_IPV6; 713 714 len = m->m_pkthdr.len; 715 if (! IF_HANDOFF(ifq, m, NULL)) 716 return; 717 schednetisr(isr); 718 ifp->if_ipackets++; 719 ifp->if_ibytes += len; 720 } 721 722 /* ARGSUSED */ 723 static void 724 stf_rtrequest(cmd, rt, info) 725 int cmd; 726 struct rtentry *rt; 727 struct rt_addrinfo *info; 728 { 729 730 if (rt) 731 rt->rt_rmx.rmx_mtu = IPV6_MMTU; 732 } 733 734 static int 735 stf_ioctl(ifp, cmd, data) 736 struct ifnet *ifp; 737 u_long cmd; 738 caddr_t data; 739 { 740 struct ifaddr *ifa; 741 struct ifreq *ifr; 742 struct sockaddr_in6 *sin6; 743 struct in_addr addr; 744 int error; 745 746 error = 0; 747 switch (cmd) { 748 case SIOCSIFADDR: 749 ifa = (struct ifaddr *)data; 750 if (ifa == NULL || ifa->ifa_addr->sa_family != AF_INET6) { 751 error = EAFNOSUPPORT; 752 break; 753 } 754 sin6 = (struct sockaddr_in6 *)ifa->ifa_addr; 755 if (!IN6_IS_ADDR_6TO4(&sin6->sin6_addr)) { 756 error = EINVAL; 757 break; 758 } 759 bcopy(GET_V4(&sin6->sin6_addr), &addr, sizeof(addr)); 760 if (isrfc1918addr(&addr)) { 761 error = EINVAL; 762 break; 763 } 764 765 ifa->ifa_rtrequest = stf_rtrequest; 766 ifp->if_flags |= IFF_UP; 767 break; 768 769 case SIOCADDMULTI: 770 case SIOCDELMULTI: 771 ifr = (struct ifreq *)data; 772 if (ifr && ifr->ifr_addr.sa_family == AF_INET6) 773 ; 774 else 775 error = EAFNOSUPPORT; 776 break; 777 778 default: 779 error = EINVAL; 780 break; 781 } 782 783 return error; 784 } 785