if_stf.c revision 1.17
1 /* $NetBSD: if_stf.c,v 1.17 2001/07/18 16:43:10 thorpej 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 #if defined(__FreeBSD__) && __FreeBSD__ >= 3 78 #include "opt_inet.h" 79 #include "opt_inet6.h" 80 #endif 81 #ifdef __NetBSD__ 82 #include "opt_inet.h" 83 #endif 84 85 #include <sys/param.h> 86 #include <sys/systm.h> 87 #include <sys/socket.h> 88 #include <sys/sockio.h> 89 #include <sys/mbuf.h> 90 #include <sys/errno.h> 91 #if !(defined(__FreeBSD__) && __FreeBSD__ >= 3) 92 #include <sys/ioctl.h> 93 #endif 94 #include <sys/protosw.h> 95 #ifdef __FreeBSD__ 96 #include <sys/kernel.h> 97 #endif 98 #include <sys/queue.h> 99 #include <sys/syslog.h> 100 #include <machine/cpu.h> 101 102 #if defined(__FreeBSD__) && __FreeBSD__ >= 3 103 #include <sys/malloc.h> 104 #endif 105 106 #include <net/if.h> 107 #include <net/route.h> 108 #include <net/netisr.h> 109 #include <net/if_types.h> 110 #include <net/if_stf.h> 111 112 #include <netinet/in.h> 113 #include <netinet/in_systm.h> 114 #include <netinet/ip.h> 115 #include <netinet/ip_var.h> 116 #include <netinet/in_var.h> 117 118 #include <netinet/ip6.h> 119 #include <netinet6/ip6_var.h> 120 #include <netinet6/in6_gif.h> 121 #include <netinet6/in6_var.h> 122 #include <netinet/ip_ecn.h> 123 124 #include <netinet/ip_encap.h> 125 126 #include <machine/stdarg.h> 127 128 #include <net/net_osdep.h> 129 130 #if defined(__FreeBSD__) && __FreeBSD__ >= 4 131 #include "bpf.h" 132 #define NBPFILTER NBPF 133 #else 134 #include "bpfilter.h" 135 #endif 136 #include "stf.h" 137 #include "gif.h" /*XXX*/ 138 139 #if NBPFILTER > 0 140 #include <net/bpf.h> 141 #endif 142 143 #if NGIF > 0 144 #include <net/if_gif.h> 145 #endif 146 147 #if NSTF > 0 148 149 #define IN6_IS_ADDR_6TO4(x) (ntohs((x)->s6_addr16[0]) == 0x2002) 150 #define GET_V4(x) ((struct in_addr *)(&(x)->s6_addr16[1])) 151 152 struct stf_softc { 153 struct ifnet sc_if; /* common area */ 154 union { 155 struct route __sc_ro4; 156 struct route_in6 __sc_ro6; /* just for safety */ 157 } __sc_ro46; 158 #define sc_ro __sc_ro46.__sc_ro4 159 const struct encaptab *encap_cookie; 160 LIST_ENTRY(stf_softc) sc_list; 161 }; 162 163 LIST_HEAD(, stf_softc) stf_softc_list; 164 165 int stf_clone_create __P((struct if_clone *, int)); 166 void stf_clone_destroy __P((struct ifnet *)); 167 168 struct if_clone stf_cloner = 169 IF_CLONE_INITIALIZER("stf", stf_clone_create, stf_clone_destroy); 170 171 #if NGIF > 0 172 extern int ip_gif_ttl; /*XXX*/ 173 #else 174 static int ip_gif_ttl = 40; /*XXX*/ 175 #endif 176 177 extern struct protosw in_stf_protosw; 178 179 #ifdef __FreeBSD__ 180 void stfattach __P((void *)); 181 #else 182 void stfattach __P((int)); 183 #endif 184 static int stf_encapcheck __P((const struct mbuf *, int, int, void *)); 185 static struct in6_ifaddr *stf_getsrcifa6 __P((struct ifnet *)); 186 static int stf_output __P((struct ifnet *, struct mbuf *, struct sockaddr *, 187 struct rtentry *)); 188 static int stf_checkaddr4 __P((struct stf_softc *, struct in_addr *, 189 struct ifnet *)); 190 static int stf_checkaddr6 __P((struct stf_softc *, struct in6_addr *, 191 struct ifnet *)); 192 static void stf_rtrequest __P((int, struct rtentry *, struct rt_addrinfo *)); 193 #if defined(__FreeBSD__) && __FreeBSD__ < 3 194 static int stf_ioctl __P((struct ifnet *, int, caddr_t)); 195 #else 196 static int stf_ioctl __P((struct ifnet *, u_long, caddr_t)); 197 #endif 198 199 /* ARGSUSED */ 200 void 201 stfattach(count) 202 int count; 203 { 204 205 LIST_INIT(&stf_softc_list); 206 if_clone_attach(&stf_cloner); 207 } 208 209 int 210 stf_clone_create(ifc, unit) 211 struct if_clone *ifc; 212 int unit; 213 { 214 struct stf_softc *sc; 215 216 if (LIST_FIRST(&stf_softc_list) != NULL) { 217 /* Only one stf interface is allowed. */ 218 return (EEXIST); 219 } 220 221 sc = malloc(sizeof(struct stf_softc), M_DEVBUF, M_WAIT); 222 memset(sc, 0, sizeof(struct stf_softc)); 223 224 sprintf(sc->sc_if.if_xname, "%s%d", ifc->ifc_name, unit); 225 226 sc->encap_cookie = encap_attach_func(AF_INET, IPPROTO_IPV6, 227 stf_encapcheck, &in_stf_protosw, sc); 228 if (sc->encap_cookie == NULL) { 229 printf("%s: unable to attach encap\n", if_name(&sc->sc_if)); 230 free(sc, M_DEVBUF); 231 return (EIO); /* XXX */ 232 } 233 234 sc->sc_if.if_mtu = IPV6_MMTU; 235 sc->sc_if.if_flags = 0; 236 sc->sc_if.if_ioctl = stf_ioctl; 237 sc->sc_if.if_output = stf_output; 238 sc->sc_if.if_type = IFT_STF; 239 sc->sc_if.if_dlt = DLT_NULL; 240 #if defined(__FreeBSD__) && __FreeBSD__ >= 4 241 sc->sc_if.if_snd.ifq_maxlen = IFQ_MAXLEN; 242 #endif 243 if_attach(&sc->sc_if); 244 if_alloc_sadl(&sc->sc_if); 245 #if NBPFILTER > 0 246 bpfattach(&sc->sc_if, DLT_NULL, sizeof(u_int)); 247 #endif 248 LIST_INSERT_HEAD(&stf_softc_list, sc, sc_list); 249 return (0); 250 } 251 252 void 253 stf_clone_destroy(ifp) 254 struct ifnet *ifp; 255 { 256 struct stf_softc *sc = (void *) ifp; 257 258 LIST_REMOVE(sc, sc_list); 259 encap_detach(sc->encap_cookie); 260 #if NBPFILTER > 0 261 bpfdetach(ifp); 262 #endif 263 if_detach(ifp); 264 free(sc, M_DEVBUF); 265 } 266 267 #ifdef __FreeBSD__ 268 PSEUDO_SET(stfattach, if_stf); 269 #endif 270 271 static int 272 stf_encapcheck(m, off, proto, arg) 273 const struct mbuf *m; 274 int off; 275 int proto; 276 void *arg; 277 { 278 struct ip ip; 279 struct in6_ifaddr *ia6; 280 struct stf_softc *sc; 281 struct in_addr a, b; 282 283 sc = (struct stf_softc *)arg; 284 if (sc == NULL) 285 return 0; 286 287 if ((sc->sc_if.if_flags & IFF_UP) == 0) 288 return 0; 289 290 /* IFF_LINK0 means "no decapsulation" */ 291 if ((sc->sc_if.if_flags & IFF_LINK0) != 0) 292 return 0; 293 294 if (proto != IPPROTO_IPV6) 295 return 0; 296 297 /* LINTED const cast */ 298 m_copydata((struct mbuf *)m, 0, sizeof(ip), (caddr_t)&ip); 299 300 if (ip.ip_v != 4) 301 return 0; 302 303 ia6 = stf_getsrcifa6(&sc->sc_if); 304 if (ia6 == NULL) 305 return 0; 306 307 /* 308 * check if IPv4 dst matches the IPv4 address derived from the 309 * local 6to4 address. 310 * success on: dst = 10.1.1.1, ia6->ia_addr = 2002:0a01:0101:... 311 */ 312 if (bcmp(GET_V4(&ia6->ia_addr.sin6_addr), &ip.ip_dst, 313 sizeof(ip.ip_dst)) != 0) 314 return 0; 315 316 /* 317 * check if IPv4 src matches the IPv4 address derived from the 318 * local 6to4 address masked by prefixmask. 319 * success on: src = 10.1.1.1, ia6->ia_addr = 2002:0a00:.../24 320 * fail on: src = 10.1.1.1, ia6->ia_addr = 2002:0b00:.../24 321 */ 322 memset(&a, 0, sizeof(a)); 323 a.s_addr = GET_V4(&ia6->ia_addr.sin6_addr)->s_addr; 324 a.s_addr &= GET_V4(&ia6->ia_prefixmask.sin6_addr)->s_addr; 325 b = ip.ip_src; 326 b.s_addr &= GET_V4(&ia6->ia_prefixmask.sin6_addr)->s_addr; 327 if (a.s_addr != b.s_addr) 328 return 0; 329 330 /* stf interface makes single side match only */ 331 return 32; 332 } 333 334 static struct in6_ifaddr * 335 stf_getsrcifa6(ifp) 336 struct ifnet *ifp; 337 { 338 struct ifaddr *ia; 339 struct in_ifaddr *ia4; 340 struct sockaddr_in6 *sin6; 341 struct in_addr in; 342 343 #if defined(__bsdi__) || (defined(__FreeBSD__) && __FreeBSD__ < 3) 344 for (ia = ifp->if_addrlist; ia; ia = ia->ifa_next) 345 #else 346 for (ia = ifp->if_addrlist.tqh_first; 347 ia; 348 ia = ia->ifa_list.tqe_next) 349 #endif 350 { 351 if (ia->ifa_addr == NULL) 352 continue; 353 if (ia->ifa_addr->sa_family != AF_INET6) 354 continue; 355 sin6 = (struct sockaddr_in6 *)ia->ifa_addr; 356 if (!IN6_IS_ADDR_6TO4(&sin6->sin6_addr)) 357 continue; 358 359 bcopy(GET_V4(&sin6->sin6_addr), &in, sizeof(in)); 360 #ifdef __NetBSD__ 361 INADDR_TO_IA(in, ia4); 362 #else 363 #ifdef __OpenBSD__ 364 for (ia4 = in_ifaddr.tqh_first; 365 ia4; 366 ia4 = ia4->ia_list.tqe_next) 367 #elif defined(__FreeBSD__) && __FreeBSD__ >= 3 368 for (ia4 = TAILQ_FIRST(&in_ifaddrhead); 369 ia4; 370 ia4 = TAILQ_NEXT(ia4, ia_link)) 371 #else 372 for (ia4 = in_ifaddr; ia4 != NULL; ia4 = ia4->ia_next) 373 #endif 374 { 375 if (ia4->ia_addr.sin_addr.s_addr == in.s_addr) 376 break; 377 } 378 #endif 379 if (ia4 == NULL) 380 continue; 381 382 return (struct in6_ifaddr *)ia; 383 } 384 385 return NULL; 386 } 387 388 static int 389 stf_output(ifp, m, dst, rt) 390 struct ifnet *ifp; 391 struct mbuf *m; 392 struct sockaddr *dst; 393 struct rtentry *rt; 394 { 395 struct stf_softc *sc; 396 struct sockaddr_in6 *dst6; 397 struct in_addr *in4; 398 struct sockaddr_in *dst4; 399 u_int8_t tos; 400 struct ip *ip; 401 struct ip6_hdr *ip6; 402 struct in6_ifaddr *ia6; 403 404 sc = (struct stf_softc*)ifp; 405 dst6 = (struct sockaddr_in6 *)dst; 406 407 /* just in case */ 408 if ((ifp->if_flags & IFF_UP) == 0) { 409 m_freem(m); 410 return ENETDOWN; 411 } 412 413 /* 414 * If we don't have an ip4 address that match my inner ip6 address, 415 * we shouldn't generate output. Without this check, we'll end up 416 * using wrong IPv4 source. 417 */ 418 ia6 = stf_getsrcifa6(ifp); 419 if (ia6 == NULL) { 420 m_freem(m); 421 return ENETDOWN; 422 } 423 424 if (m->m_len < sizeof(*ip6)) { 425 m = m_pullup(m, sizeof(*ip6)); 426 if (!m) 427 return ENOBUFS; 428 } 429 ip6 = mtod(m, struct ip6_hdr *); 430 tos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; 431 432 /* 433 * Pickup the right outer dst addr from the list of candidates. 434 * ip6_dst has priority as it may be able to give us shorter IPv4 hops. 435 */ 436 if (IN6_IS_ADDR_6TO4(&ip6->ip6_dst)) 437 in4 = GET_V4(&ip6->ip6_dst); 438 else if (IN6_IS_ADDR_6TO4(&dst6->sin6_addr)) 439 in4 = GET_V4(&dst6->sin6_addr); 440 else { 441 m_freem(m); 442 return ENETUNREACH; 443 } 444 445 #if NBPFILTER > 0 446 if (ifp->if_bpf) { 447 /* 448 * We need to prepend the address family as 449 * a four byte field. Cons up a dummy header 450 * to pacify bpf. This is safe because bpf 451 * will only read from the mbuf (i.e., it won't 452 * try to free it or keep a pointer a to it). 453 */ 454 struct mbuf m0; 455 u_int32_t af = AF_INET6; 456 457 m0.m_next = m; 458 m0.m_len = 4; 459 m0.m_data = (char *)⁡ 460 461 #ifdef HAVE_OLD_BPF 462 bpf_mtap(ifp, &m0); 463 #else 464 bpf_mtap(ifp->if_bpf, &m0); 465 #endif 466 } 467 #endif /*NBPFILTER > 0*/ 468 469 M_PREPEND(m, sizeof(struct ip), M_DONTWAIT); 470 if (m && m->m_len < sizeof(struct ip)) 471 m = m_pullup(m, sizeof(struct ip)); 472 if (m == NULL) 473 return ENOBUFS; 474 ip = mtod(m, struct ip *); 475 476 memset(ip, 0, sizeof(*ip)); 477 478 bcopy(GET_V4(&((struct sockaddr_in6 *)&ia6->ia_addr)->sin6_addr), 479 &ip->ip_src, sizeof(ip->ip_src)); 480 bcopy(in4, &ip->ip_dst, sizeof(ip->ip_dst)); 481 ip->ip_p = IPPROTO_IPV6; 482 ip->ip_ttl = ip_gif_ttl; /*XXX*/ 483 ip->ip_len = m->m_pkthdr.len; /*host order*/ 484 if (ifp->if_flags & IFF_LINK1) 485 ip_ecn_ingress(ECN_ALLOWED, &ip->ip_tos, &tos); 486 else 487 ip_ecn_ingress(ECN_NOCARE, &ip->ip_tos, &tos); 488 489 dst4 = (struct sockaddr_in *)&sc->sc_ro.ro_dst; 490 if (dst4->sin_family != AF_INET || 491 bcmp(&dst4->sin_addr, &ip->ip_dst, sizeof(ip->ip_dst)) != 0) { 492 /* cache route doesn't match */ 493 dst4->sin_family = AF_INET; 494 dst4->sin_len = sizeof(struct sockaddr_in); 495 bcopy(&ip->ip_dst, &dst4->sin_addr, sizeof(dst4->sin_addr)); 496 if (sc->sc_ro.ro_rt) { 497 RTFREE(sc->sc_ro.ro_rt); 498 sc->sc_ro.ro_rt = NULL; 499 } 500 } 501 502 if (sc->sc_ro.ro_rt == NULL) { 503 rtalloc(&sc->sc_ro); 504 if (sc->sc_ro.ro_rt == NULL) { 505 m_freem(m); 506 return ENETUNREACH; 507 } 508 } 509 510 #ifndef __OpenBSD__ 511 return ip_output(m, NULL, &sc->sc_ro, 0, NULL); 512 #else 513 return ip_output(m, NULL, &sc->sc_ro, 0, NULL, NULL); 514 #endif 515 } 516 517 static int 518 stf_checkaddr4(sc, in, inifp) 519 struct stf_softc *sc; 520 struct in_addr *in; 521 struct ifnet *inifp; /* incoming interface */ 522 { 523 struct in_ifaddr *ia4; 524 525 /* 526 * reject packets with the following address: 527 * 224.0.0.0/4 0.0.0.0/8 127.0.0.0/8 255.0.0.0/8 528 */ 529 if (IN_MULTICAST(in->s_addr)) 530 return -1; 531 switch ((ntohl(in->s_addr) & 0xff000000) >> 24) { 532 case 0: case 127: case 255: 533 return -1; 534 } 535 536 /* 537 * reject packets with broadcast 538 */ 539 #if defined(__OpenBSD__) || defined(__NetBSD__) 540 for (ia4 = in_ifaddr.tqh_first; ia4; ia4 = ia4->ia_list.tqe_next) 541 #elif defined(__FreeBSD__) && __FreeBSD__ >= 3 542 for (ia4 = TAILQ_FIRST(&in_ifaddrhead); 543 ia4; 544 ia4 = TAILQ_NEXT(ia4, ia_link)) 545 #else 546 for (ia4 = in_ifaddr; ia4 != NULL; ia4 = ia4->ia_next) 547 #endif 548 { 549 if ((ia4->ia_ifa.ifa_ifp->if_flags & IFF_BROADCAST) == 0) 550 continue; 551 if (in->s_addr == ia4->ia_broadaddr.sin_addr.s_addr) 552 return -1; 553 } 554 555 /* 556 * perform ingress filter 557 */ 558 if (sc && (sc->sc_if.if_flags & IFF_LINK2) == 0 && inifp) { 559 struct sockaddr_in sin; 560 struct rtentry *rt; 561 562 memset(&sin, 0, sizeof(sin)); 563 sin.sin_family = AF_INET; 564 sin.sin_len = sizeof(struct sockaddr_in); 565 sin.sin_addr = *in; 566 #ifdef __FreeBSD__ 567 rt = rtalloc1((struct sockaddr *)&sin, 0, 0UL); 568 #else 569 rt = rtalloc1((struct sockaddr *)&sin, 0); 570 #endif 571 if (!rt || rt->rt_ifp != inifp) { 572 #if 0 573 log(LOG_WARNING, "%s: packet from 0x%x dropped " 574 "due to ingress filter\n", if_name(&sc->sc_if), 575 (u_int32_t)ntohl(sin.sin_addr.s_addr)); 576 #endif 577 if (rt) 578 rtfree(rt); 579 return -1; 580 } 581 rtfree(rt); 582 } 583 584 return 0; 585 } 586 587 static int 588 stf_checkaddr6(sc, in6, inifp) 589 struct stf_softc *sc; 590 struct in6_addr *in6; 591 struct ifnet *inifp; /* incoming interface */ 592 { 593 /* 594 * check 6to4 addresses 595 */ 596 if (IN6_IS_ADDR_6TO4(in6)) 597 return stf_checkaddr4(sc, GET_V4(in6), inifp); 598 599 /* 600 * reject anything that look suspicious. the test is implemented 601 * in ip6_input too, but we check here as well to 602 * (1) reject bad packets earlier, and 603 * (2) to be safe against future ip6_input change. 604 */ 605 if (IN6_IS_ADDR_V4COMPAT(in6) || IN6_IS_ADDR_V4MAPPED(in6)) 606 return -1; 607 608 return 0; 609 } 610 611 void 612 #if __STDC__ 613 in_stf_input(struct mbuf *m, ...) 614 #else 615 in_stf_input(m, va_alist) 616 struct mbuf *m; 617 #endif 618 { 619 int off, proto; 620 struct stf_softc *sc; 621 struct ip *ip; 622 struct ip6_hdr *ip6; 623 u_int8_t otos, itos; 624 int s, isr; 625 struct ifqueue *ifq = NULL; 626 struct ifnet *ifp; 627 va_list ap; 628 629 va_start(ap, m); 630 off = va_arg(ap, int); 631 proto = va_arg(ap, int); 632 va_end(ap); 633 634 if (proto != IPPROTO_IPV6) { 635 m_freem(m); 636 return; 637 } 638 639 ip = mtod(m, struct ip *); 640 641 sc = (struct stf_softc *)encap_getarg(m); 642 643 if (sc == NULL || (sc->sc_if.if_flags & IFF_UP) == 0) { 644 m_freem(m); 645 return; 646 } 647 648 ifp = &sc->sc_if; 649 650 /* 651 * perform sanity check against outer src/dst. 652 * for source, perform ingress filter as well. 653 */ 654 if (stf_checkaddr4(sc, &ip->ip_dst, NULL) < 0 || 655 stf_checkaddr4(sc, &ip->ip_src, m->m_pkthdr.rcvif) < 0) { 656 m_freem(m); 657 return; 658 } 659 660 otos = ip->ip_tos; 661 m_adj(m, off); 662 663 if (m->m_len < sizeof(*ip6)) { 664 m = m_pullup(m, sizeof(*ip6)); 665 if (!m) 666 return; 667 } 668 ip6 = mtod(m, struct ip6_hdr *); 669 670 /* 671 * perform sanity check against inner src/dst. 672 * for source, perform ingress filter as well. 673 */ 674 if (stf_checkaddr6(sc, &ip6->ip6_dst, NULL) < 0 || 675 stf_checkaddr6(sc, &ip6->ip6_src, m->m_pkthdr.rcvif) < 0) { 676 m_freem(m); 677 return; 678 } 679 680 itos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; 681 if ((ifp->if_flags & IFF_LINK1) != 0) 682 ip_ecn_egress(ECN_ALLOWED, &otos, &itos); 683 else 684 ip_ecn_egress(ECN_NOCARE, &otos, &itos); 685 ip6->ip6_flow &= ~htonl(0xff << 20); 686 ip6->ip6_flow |= htonl((u_int32_t)itos << 20); 687 688 m->m_pkthdr.rcvif = ifp; 689 690 #if NBPFILTER > 0 691 if (ifp->if_bpf) { 692 /* 693 * We need to prepend the address family as 694 * a four byte field. Cons up a dummy header 695 * to pacify bpf. This is safe because bpf 696 * will only read from the mbuf (i.e., it won't 697 * try to free it or keep a pointer a to it). 698 */ 699 struct mbuf m0; 700 u_int32_t af = AF_INET6; 701 702 m0.m_next = m; 703 m0.m_len = 4; 704 m0.m_data = (char *)⁡ 705 706 #ifdef HAVE_OLD_BPF 707 bpf_mtap(ifp, &m0); 708 #else 709 bpf_mtap(ifp->if_bpf, &m0); 710 #endif 711 } 712 #endif /*NBPFILTER > 0*/ 713 714 /* 715 * Put the packet to the network layer input queue according to the 716 * specified address family. 717 * See net/if_gif.c for possible issues with packet processing 718 * reorder due to extra queueing. 719 */ 720 ifq = &ip6intrq; 721 isr = NETISR_IPV6; 722 723 s = splnet(); 724 if (IF_QFULL(ifq)) { 725 IF_DROP(ifq); /* update statistics */ 726 m_freem(m); 727 splx(s); 728 return; 729 } 730 IF_ENQUEUE(ifq, m); 731 schednetisr(isr); 732 ifp->if_ipackets++; 733 ifp->if_ibytes += m->m_pkthdr.len; 734 splx(s); 735 } 736 737 /* ARGSUSED */ 738 static void 739 stf_rtrequest(cmd, rt, info) 740 int cmd; 741 struct rtentry *rt; 742 struct rt_addrinfo *info; 743 { 744 745 if (rt) 746 rt->rt_rmx.rmx_mtu = IPV6_MMTU; 747 } 748 749 static int 750 stf_ioctl(ifp, cmd, data) 751 struct ifnet *ifp; 752 #if defined(__FreeBSD__) && __FreeBSD__ < 3 753 int cmd; 754 #else 755 u_long cmd; 756 #endif 757 caddr_t data; 758 { 759 struct ifaddr *ifa; 760 struct ifreq *ifr; 761 struct sockaddr_in6 *sin6; 762 int error; 763 764 error = 0; 765 switch (cmd) { 766 case SIOCSIFADDR: 767 ifa = (struct ifaddr *)data; 768 if (ifa == NULL || ifa->ifa_addr->sa_family != AF_INET6) { 769 error = EAFNOSUPPORT; 770 break; 771 } 772 sin6 = (struct sockaddr_in6 *)ifa->ifa_addr; 773 if (IN6_IS_ADDR_6TO4(&sin6->sin6_addr)) { 774 ifa->ifa_rtrequest = stf_rtrequest; 775 ifp->if_flags |= IFF_UP; 776 } else 777 error = EINVAL; 778 break; 779 780 case SIOCADDMULTI: 781 case SIOCDELMULTI: 782 ifr = (struct ifreq *)data; 783 if (ifr && ifr->ifr_addr.sa_family == AF_INET6) 784 ; 785 else 786 error = EAFNOSUPPORT; 787 break; 788 789 default: 790 error = EINVAL; 791 break; 792 } 793 794 return error; 795 } 796 797 #endif /* NSTF > 0 */ 798
Indexes created Tue Sep 30 07:10:03 GMT 2025