1 /* $NetBSD: if_stf.c,v 1.39 2004/04/26 01:41:15 matt Exp $ */ 2 /* $KAME: if_stf.c,v 1.62 2001/06/07 22:32:16 itojun 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 <sys/cdefs.h> 78 __KERNEL_RCSID(0, "$NetBSD: if_stf.c,v 1.39 2004/04/26 01:41:15 matt Exp $"); 79 80 #include "opt_inet.h" 81 82 #include <sys/param.h> 83 #include <sys/systm.h> 84 #include <sys/socket.h> 85 #include <sys/sockio.h> 86 #include <sys/mbuf.h> 87 #include <sys/errno.h> 88 #include <sys/ioctl.h> 89 #include <sys/protosw.h> 90 #include <sys/queue.h> 91 #include <sys/syslog.h> 92 #include <machine/cpu.h> 93 94 #include <net/if.h> 95 #include <net/route.h> 96 #include <net/netisr.h> 97 #include <net/if_types.h> 98 #include <net/if_stf.h> 99 100 #include <netinet/in.h> 101 #include <netinet/in_systm.h> 102 #include <netinet/ip.h> 103 #include <netinet/ip_var.h> 104 #include <netinet/in_var.h> 105 106 #include <netinet/ip6.h> 107 #include <netinet6/ip6_var.h> 108 #include <netinet6/in6_gif.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 "bpfilter.h" 119 #include "stf.h" 120 #include "gif.h" /*XXX*/ 121 122 #if NBPFILTER > 0 123 #include <net/bpf.h> 124 #endif 125 126 #if NGIF > 0 127 #include <net/if_gif.h> 128 #endif 129 130 #define IN6_IS_ADDR_6TO4(x) (ntohs((x)->s6_addr16[0]) == 0x2002) 131 #define GET_V4(x) ((struct in_addr *)(&(x)->s6_addr16[1])) 132 133 struct stf_softc { 134 struct ifnet sc_if; /* common area */ 135 union { 136 struct route __sc_ro4; 137 struct route_in6 __sc_ro6; /* just for safety */ 138 } __sc_ro46; 139 #define sc_ro __sc_ro46.__sc_ro4 140 const struct encaptab *encap_cookie; 141 LIST_ENTRY(stf_softc) sc_list; 142 }; 143 144 LIST_HEAD(, stf_softc) stf_softc_list; 145 146 int stf_clone_create __P((struct if_clone *, int)); 147 void stf_clone_destroy __P((struct ifnet *)); 148 149 struct if_clone stf_cloner = 150 IF_CLONE_INITIALIZER("stf", stf_clone_create, stf_clone_destroy); 151 152 #if NGIF > 0 153 extern int ip_gif_ttl; /*XXX*/ 154 #else 155 static int ip_gif_ttl = 40; /*XXX*/ 156 #endif 157 158 extern struct domain inetdomain; 159 const struct protosw in_stf_protosw = 160 { SOCK_RAW, &inetdomain, IPPROTO_IPV6, PR_ATOMIC|PR_ADDR, 161 in_stf_input, rip_output, 0, rip_ctloutput, 162 rip_usrreq, 163 0, 0, 0, 0 164 }; 165 166 void stfattach __P((int)); 167 static int stf_encapcheck __P((const struct mbuf *, int, int, void *)); 168 static struct in6_ifaddr *stf_getsrcifa6 __P((struct ifnet *)); 169 static int stf_output __P((struct ifnet *, struct mbuf *, struct sockaddr *, 170 struct rtentry *)); 171 static int isrfc1918addr __P((struct in_addr *)); 172 static int stf_checkaddr4 __P((struct stf_softc *, struct in_addr *, 173 struct ifnet *)); 174 static int stf_checkaddr6 __P((struct stf_softc *, struct in6_addr *, 175 struct ifnet *)); 176 static void stf_rtrequest __P((int, struct rtentry *, struct rt_addrinfo *)); 177 static int stf_ioctl __P((struct ifnet *, u_long, caddr_t)); 178 179 /* ARGSUSED */ 180 void 181 stfattach(count) 182 int count; 183 { 184 185 LIST_INIT(&stf_softc_list); 186 if_clone_attach(&stf_cloner); 187 } 188 189 int 190 stf_clone_create(ifc, unit) 191 struct if_clone *ifc; 192 int unit; 193 { 194 struct stf_softc *sc; 195 196 if (LIST_FIRST(&stf_softc_list) != NULL) { 197 /* Only one stf interface is allowed. */ 198 return (EEXIST); 199 } 200 201 sc = malloc(sizeof(struct stf_softc), M_DEVBUF, M_WAIT); 202 memset(sc, 0, sizeof(struct stf_softc)); 203 204 snprintf(sc->sc_if.if_xname, sizeof(sc->sc_if.if_xname), "%s%d", 205 ifc->ifc_name, unit); 206 207 sc->encap_cookie = encap_attach_func(AF_INET, IPPROTO_IPV6, 208 stf_encapcheck, &in_stf_protosw, sc); 209 if (sc->encap_cookie == NULL) { 210 printf("%s: unable to attach encap\n", if_name(&sc->sc_if)); 211 free(sc, M_DEVBUF); 212 return (EIO); /* XXX */ 213 } 214 215 sc->sc_if.if_mtu = IPV6_MMTU; 216 sc->sc_if.if_flags = 0; 217 sc->sc_if.if_ioctl = stf_ioctl; 218 sc->sc_if.if_output = stf_output; 219 sc->sc_if.if_type = IFT_STF; 220 sc->sc_if.if_dlt = DLT_NULL; 221 if_attach(&sc->sc_if); 222 if_alloc_sadl(&sc->sc_if); 223 #if NBPFILTER > 0 224 bpfattach(&sc->sc_if, DLT_NULL, sizeof(u_int)); 225 #endif 226 LIST_INSERT_HEAD(&stf_softc_list, sc, sc_list); 227 return (0); 228 } 229 230 void 231 stf_clone_destroy(ifp) 232 struct ifnet *ifp; 233 { 234 struct stf_softc *sc = (void *) ifp; 235 236 LIST_REMOVE(sc, sc_list); 237 encap_detach(sc->encap_cookie); 238 #if NBPFILTER > 0 239 bpfdetach(ifp); 240 #endif 241 if_detach(ifp); 242 free(sc, M_DEVBUF); 243 } 244 245 static int 246 stf_encapcheck(m, off, proto, arg) 247 const struct mbuf *m; 248 int off; 249 int proto; 250 void *arg; 251 { 252 struct ip ip; 253 struct in6_ifaddr *ia6; 254 struct stf_softc *sc; 255 struct in_addr a, b; 256 257 sc = (struct stf_softc *)arg; 258 if (sc == NULL) 259 return 0; 260 261 if ((sc->sc_if.if_flags & IFF_UP) == 0) 262 return 0; 263 264 /* IFF_LINK0 means "no decapsulation" */ 265 if ((sc->sc_if.if_flags & IFF_LINK0) != 0) 266 return 0; 267 268 if (proto != IPPROTO_IPV6) 269 return 0; 270 271 /* LINTED const cast */ 272 m_copydata((struct mbuf *)m, 0, sizeof(ip), (caddr_t)&ip); 273 274 if (ip.ip_v != 4) 275 return 0; 276 277 ia6 = stf_getsrcifa6(&sc->sc_if); 278 if (ia6 == NULL) 279 return 0; 280 281 /* 282 * check if IPv4 dst matches the IPv4 address derived from the 283 * local 6to4 address. 284 * success on: dst = 10.1.1.1, ia6->ia_addr = 2002:0a01:0101:... 285 */ 286 if (bcmp(GET_V4(&ia6->ia_addr.sin6_addr), &ip.ip_dst, 287 sizeof(ip.ip_dst)) != 0) 288 return 0; 289 290 /* 291 * check if IPv4 src matches the IPv4 address derived from the 292 * local 6to4 address masked by prefixmask. 293 * success on: src = 10.1.1.1, ia6->ia_addr = 2002:0a00:.../24 294 * fail on: src = 10.1.1.1, ia6->ia_addr = 2002:0b00:.../24 295 */ 296 memset(&a, 0, sizeof(a)); 297 a.s_addr = GET_V4(&ia6->ia_addr.sin6_addr)->s_addr; 298 a.s_addr &= GET_V4(&ia6->ia_prefixmask.sin6_addr)->s_addr; 299 b = ip.ip_src; 300 b.s_addr &= GET_V4(&ia6->ia_prefixmask.sin6_addr)->s_addr; 301 if (a.s_addr != b.s_addr) 302 return 0; 303 304 /* stf interface makes single side match only */ 305 return 32; 306 } 307 308 static struct in6_ifaddr * 309 stf_getsrcifa6(ifp) 310 struct ifnet *ifp; 311 { 312 struct ifaddr *ia; 313 struct in_ifaddr *ia4; 314 struct sockaddr_in6 *sin6; 315 struct in_addr in; 316 317 TAILQ_FOREACH(ia, &ifp->if_addrlist, ifa_list) 318 { 319 if (ia->ifa_addr == NULL) 320 continue; 321 if (ia->ifa_addr->sa_family != AF_INET6) 322 continue; 323 sin6 = (struct sockaddr_in6 *)ia->ifa_addr; 324 if (!IN6_IS_ADDR_6TO4(&sin6->sin6_addr)) 325 continue; 326 327 bcopy(GET_V4(&sin6->sin6_addr), &in, sizeof(in)); 328 INADDR_TO_IA(in, ia4); 329 if (ia4 == NULL) 330 continue; 331 332 return (struct in6_ifaddr *)ia; 333 } 334 335 return NULL; 336 } 337 338 static int 339 stf_output(ifp, m, dst, rt) 340 struct ifnet *ifp; 341 struct mbuf *m; 342 struct sockaddr *dst; 343 struct rtentry *rt; 344 { 345 struct stf_softc *sc; 346 struct sockaddr_in6 *dst6; 347 struct in_addr *in4; 348 struct sockaddr_in *dst4; 349 u_int8_t tos; 350 struct ip *ip; 351 struct ip6_hdr *ip6; 352 struct in6_ifaddr *ia6; 353 354 sc = (struct stf_softc*)ifp; 355 dst6 = (struct sockaddr_in6 *)dst; 356 357 /* just in case */ 358 if ((ifp->if_flags & IFF_UP) == 0) { 359 m_freem(m); 360 return ENETDOWN; 361 } 362 363 /* 364 * If we don't have an ip4 address that match my inner ip6 address, 365 * we shouldn't generate output. Without this check, we'll end up 366 * using wrong IPv4 source. 367 */ 368 ia6 = stf_getsrcifa6(ifp); 369 if (ia6 == NULL) { 370 m_freem(m); 371 ifp->if_oerrors++; 372 return ENETDOWN; 373 } 374 375 if (m->m_len < sizeof(*ip6)) { 376 m = m_pullup(m, sizeof(*ip6)); 377 if (m == NULL) { 378 ifp->if_oerrors++; 379 return ENOBUFS; 380 } 381 } 382 ip6 = mtod(m, struct ip6_hdr *); 383 tos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; 384 385 /* 386 * Pickup the right outer dst addr from the list of candidates. 387 * ip6_dst has priority as it may be able to give us shorter IPv4 hops. 388 */ 389 if (IN6_IS_ADDR_6TO4(&ip6->ip6_dst)) 390 in4 = GET_V4(&ip6->ip6_dst); 391 else if (IN6_IS_ADDR_6TO4(&dst6->sin6_addr)) 392 in4 = GET_V4(&dst6->sin6_addr); 393 else { 394 m_freem(m); 395 ifp->if_oerrors++; 396 return ENETUNREACH; 397 } 398 399 #if NBPFILTER > 0 400 if (ifp->if_bpf) { 401 /* 402 * We need to prepend the address family as 403 * a four byte field. Cons up a dummy header 404 * to pacify bpf. This is safe because bpf 405 * will only read from the mbuf (i.e., it won't 406 * try to free it or keep a pointer a to it). 407 */ 408 struct mbuf m0; 409 u_int32_t af = AF_INET6; 410 411 m0.m_flags = 0; 412 m0.m_next = m; 413 m0.m_len = 4; 414 m0.m_data = (char *)⁡ 415 416 #ifdef HAVE_OLD_BPF 417 bpf_mtap(ifp, &m0); 418 #else 419 bpf_mtap(ifp->if_bpf, &m0); 420 #endif 421 } 422 #endif /*NBPFILTER > 0*/ 423 424 M_PREPEND(m, sizeof(struct ip), M_DONTWAIT); 425 if (m && m->m_len < sizeof(struct ip)) 426 m = m_pullup(m, sizeof(struct ip)); 427 if (m == NULL) { 428 ifp->if_oerrors++; 429 return ENOBUFS; 430 } 431 ip = mtod(m, struct ip *); 432 433 memset(ip, 0, sizeof(*ip)); 434 435 bcopy(GET_V4(&((struct sockaddr_in6 *)&ia6->ia_addr)->sin6_addr), 436 &ip->ip_src, sizeof(ip->ip_src)); 437 bcopy(in4, &ip->ip_dst, sizeof(ip->ip_dst)); 438 ip->ip_p = IPPROTO_IPV6; 439 ip->ip_ttl = ip_gif_ttl; /*XXX*/ 440 ip->ip_len = htons(m->m_pkthdr.len); 441 if (ifp->if_flags & IFF_LINK1) 442 ip_ecn_ingress(ECN_ALLOWED, &ip->ip_tos, &tos); 443 else 444 ip_ecn_ingress(ECN_NOCARE, &ip->ip_tos, &tos); 445 446 dst4 = (struct sockaddr_in *)&sc->sc_ro.ro_dst; 447 if (dst4->sin_family != AF_INET || 448 bcmp(&dst4->sin_addr, &ip->ip_dst, sizeof(ip->ip_dst)) != 0) { 449 /* cache route doesn't match */ 450 dst4->sin_family = AF_INET; 451 dst4->sin_len = sizeof(struct sockaddr_in); 452 bcopy(&ip->ip_dst, &dst4->sin_addr, sizeof(dst4->sin_addr)); 453 if (sc->sc_ro.ro_rt) { 454 RTFREE(sc->sc_ro.ro_rt); 455 sc->sc_ro.ro_rt = NULL; 456 } 457 } 458 459 if (sc->sc_ro.ro_rt == NULL) { 460 rtalloc(&sc->sc_ro); 461 if (sc->sc_ro.ro_rt == NULL) { 462 m_freem(m); 463 ifp->if_oerrors++; 464 return ENETUNREACH; 465 } 466 } 467 468 ifp->if_opackets++; 469 return ip_output(m, NULL, &sc->sc_ro, 0, 470 (struct ip_moptions *)NULL, (struct socket *)NULL); 471 } 472 473 static int 474 isrfc1918addr(in) 475 struct in_addr *in; 476 { 477 /* 478 * returns 1 if private address range: 479 * 10.0.0.0/8 172.16.0.0/12 192.168.0.0/16 480 */ 481 if ((ntohl(in->s_addr) & 0xff000000) >> 24 == 10 || 482 (ntohl(in->s_addr) & 0xfff00000) >> 16 == 172 * 256 + 16 || 483 (ntohl(in->s_addr) & 0xffff0000) >> 16 == 192 * 256 + 168) 484 return 1; 485 486 return 0; 487 } 488 489 static int 490 stf_checkaddr4(sc, in, inifp) 491 struct stf_softc *sc; 492 struct in_addr *in; 493 struct ifnet *inifp; /* incoming interface */ 494 { 495 struct in_ifaddr *ia4; 496 497 /* 498 * reject packets with the following address: 499 * 224.0.0.0/4 0.0.0.0/8 127.0.0.0/8 255.0.0.0/8 500 */ 501 if (IN_MULTICAST(in->s_addr)) 502 return -1; 503 switch ((ntohl(in->s_addr) & 0xff000000) >> 24) { 504 case 0: case 127: case 255: 505 return -1; 506 } 507 508 /* 509 * reject packets with private address range. 510 * (requirement from RFC3056 section 2 1st paragraph) 511 */ 512 if (isrfc1918addr(in)) 513 return -1; 514 515 /* 516 * reject packet with IPv4 link-local (169.254.0.0/16), 517 * as suggested in draft-savola-v6ops-6to4-security-00.txt 518 */ 519 if (((ntohl(in->s_addr) & 0xff000000) >> 24) == 169 && 520 ((ntohl(in->s_addr) & 0x00ff0000) >> 16) == 254) 521 return -1; 522 523 /* 524 * reject packets with broadcast 525 */ 526 TAILQ_FOREACH(ia4, &in_ifaddrhead, ia_list) 527 { 528 if ((ia4->ia_ifa.ifa_ifp->if_flags & IFF_BROADCAST) == 0) 529 continue; 530 if (in->s_addr == ia4->ia_broadaddr.sin_addr.s_addr) 531 return -1; 532 } 533 534 /* 535 * perform ingress filter 536 */ 537 if (sc && (sc->sc_if.if_flags & IFF_LINK2) == 0 && inifp) { 538 struct sockaddr_in sin; 539 struct rtentry *rt; 540 541 memset(&sin, 0, sizeof(sin)); 542 sin.sin_family = AF_INET; 543 sin.sin_len = sizeof(struct sockaddr_in); 544 sin.sin_addr = *in; 545 rt = rtalloc1((struct sockaddr *)&sin, 0); 546 if (!rt || rt->rt_ifp != inifp) { 547 #if 0 548 log(LOG_WARNING, "%s: packet from 0x%x dropped " 549 "due to ingress filter\n", if_name(&sc->sc_if), 550 (u_int32_t)ntohl(sin.sin_addr.s_addr)); 551 #endif 552 if (rt) 553 rtfree(rt); 554 return -1; 555 } 556 rtfree(rt); 557 } 558 559 return 0; 560 } 561 562 static int 563 stf_checkaddr6(sc, in6, inifp) 564 struct stf_softc *sc; 565 struct in6_addr *in6; 566 struct ifnet *inifp; /* incoming interface */ 567 { 568 569 /* 570 * check 6to4 addresses 571 */ 572 if (IN6_IS_ADDR_6TO4(in6)) 573 return stf_checkaddr4(sc, GET_V4(in6), inifp); 574 575 /* 576 * reject anything that look suspicious. the test is implemented 577 * in ip6_input too, but we check here as well to 578 * (1) reject bad packets earlier, and 579 * (2) to be safe against future ip6_input change. 580 */ 581 if (IN6_IS_ADDR_V4COMPAT(in6) || IN6_IS_ADDR_V4MAPPED(in6)) 582 return -1; 583 584 /* 585 * reject link-local and site-local unicast 586 * as suggested in draft-savola-v6ops-6to4-security-00.txt 587 */ 588 if (IN6_IS_ADDR_LINKLOCAL(in6) || IN6_IS_ADDR_SITELOCAL(in6)) 589 return -1; 590 591 /* 592 * reject node-local and link-local multicast 593 * as suggested in draft-savola-v6ops-6to4-security-00.txt 594 */ 595 if (IN6_IS_ADDR_MC_NODELOCAL(in6) || IN6_IS_ADDR_MC_LINKLOCAL(in6)) 596 return -1; 597 598 return 0; 599 } 600 601 void 602 in_stf_input(struct mbuf *m, ...) 603 { 604 int off, proto; 605 struct stf_softc *sc; 606 struct ip *ip; 607 struct ip6_hdr *ip6; 608 u_int8_t otos, itos; 609 int s, isr; 610 struct ifqueue *ifq = NULL; 611 struct ifnet *ifp; 612 va_list ap; 613 614 va_start(ap, m); 615 off = va_arg(ap, int); 616 proto = va_arg(ap, int); 617 va_end(ap); 618 619 if (proto != IPPROTO_IPV6) { 620 m_freem(m); 621 return; 622 } 623 624 ip = mtod(m, struct ip *); 625 626 sc = (struct stf_softc *)encap_getarg(m); 627 628 if (sc == NULL || (sc->sc_if.if_flags & IFF_UP) == 0) { 629 m_freem(m); 630 return; 631 } 632 633 ifp = &sc->sc_if; 634 635 /* 636 * perform sanity check against outer src/dst. 637 * for source, perform ingress filter as well. 638 */ 639 if (stf_checkaddr4(sc, &ip->ip_dst, NULL) < 0 || 640 stf_checkaddr4(sc, &ip->ip_src, m->m_pkthdr.rcvif) < 0) { 641 m_freem(m); 642 return; 643 } 644 645 otos = ip->ip_tos; 646 m_adj(m, off); 647 648 if (m->m_len < sizeof(*ip6)) { 649 m = m_pullup(m, sizeof(*ip6)); 650 if (!m) 651 return; 652 } 653 ip6 = mtod(m, struct ip6_hdr *); 654 655 /* 656 * perform sanity check against inner src/dst. 657 * for source, perform ingress filter as well. 658 */ 659 if (stf_checkaddr6(sc, &ip6->ip6_dst, NULL) < 0 || 660 stf_checkaddr6(sc, &ip6->ip6_src, m->m_pkthdr.rcvif) < 0) { 661 m_freem(m); 662 return; 663 } 664 665 itos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; 666 if ((ifp->if_flags & IFF_LINK1) != 0) 667 ip_ecn_egress(ECN_ALLOWED, &otos, &itos); 668 else 669 ip_ecn_egress(ECN_NOCARE, &otos, &itos); 670 ip6->ip6_flow &= ~htonl(0xff << 20); 671 ip6->ip6_flow |= htonl((u_int32_t)itos << 20); 672 673 m->m_pkthdr.rcvif = ifp; 674 675 #if NBPFILTER > 0 676 if (ifp->if_bpf) { 677 /* 678 * We need to prepend the address family as 679 * a four byte field. Cons up a dummy header 680 * to pacify bpf. This is safe because bpf 681 * will only read from the mbuf (i.e., it won't 682 * try to free it or keep a pointer a to it). 683 */ 684 struct mbuf m0; 685 u_int32_t af = AF_INET6; 686 687 m0.m_flags = 0; 688 m0.m_next = m; 689 m0.m_len = 4; 690 m0.m_data = (char *)⁡ 691 692 #ifdef HAVE_OLD_BPF 693 bpf_mtap(ifp, &m0); 694 #else 695 bpf_mtap(ifp->if_bpf, &m0); 696 #endif 697 } 698 #endif /*NBPFILTER > 0*/ 699 700 /* 701 * Put the packet to the network layer input queue according to the 702 * specified address family. 703 * See net/if_gif.c for possible issues with packet processing 704 * reorder due to extra queueing. 705 */ 706 ifq = &ip6intrq; 707 isr = NETISR_IPV6; 708 709 s = splnet(); 710 if (IF_QFULL(ifq)) { 711 IF_DROP(ifq); /* update statistics */ 712 m_freem(m); 713 splx(s); 714 return; 715 } 716 IF_ENQUEUE(ifq, m); 717 schednetisr(isr); 718 ifp->if_ipackets++; 719 ifp->if_ibytes += m->m_pkthdr.len; 720 splx(s); 721 } 722 723 /* ARGSUSED */ 724 static void 725 stf_rtrequest(cmd, rt, info) 726 int cmd; 727 struct rtentry *rt; 728 struct rt_addrinfo *info; 729 { 730 731 if (rt) 732 rt->rt_rmx.rmx_mtu = IPV6_MMTU; 733 } 734 735 static int 736 stf_ioctl(ifp, cmd, data) 737 struct ifnet *ifp; 738 u_long cmd; 739 caddr_t data; 740 { 741 struct ifaddr *ifa; 742 struct ifreq *ifr; 743 struct sockaddr_in6 *sin6; 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 !isrfc1918addr(GET_V4(&sin6->sin6_addr))) { 757 ifa->ifa_rtrequest = stf_rtrequest; 758 ifp->if_flags |= IFF_UP; 759 } else 760 error = EINVAL; 761 break; 762 763 case SIOCADDMULTI: 764 case SIOCDELMULTI: 765 ifr = (struct ifreq *)data; 766 if (ifr && ifr->ifr_addr.sa_family == AF_INET6) 767 ; 768 else 769 error = EAFNOSUPPORT; 770 break; 771 772 default: 773 error = EINVAL; 774 break; 775 } 776 777 return error; 778 } 779