if_stf.c revision 1.21
1 /* $NetBSD: if_stf.c,v 1.21 2001/11/12 23:49:43 lukem 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 1.21 2001/11/12 23:49:43 lukem Exp $"); 79 80 #if defined(__FreeBSD__) && __FreeBSD__ >= 3 81 #include "opt_inet.h" 82 #include "opt_inet6.h" 83 #endif 84 #ifdef __NetBSD__ 85 #include "opt_inet.h" 86 #endif 87 88 #include <sys/param.h> 89 #include <sys/systm.h> 90 #include <sys/socket.h> 91 #include <sys/sockio.h> 92 #include <sys/mbuf.h> 93 #include <sys/errno.h> 94 #if !(defined(__FreeBSD__) && __FreeBSD__ >= 3) 95 #include <sys/ioctl.h> 96 #endif 97 #include <sys/protosw.h> 98 #ifdef __FreeBSD__ 99 #include <sys/kernel.h> 100 #endif 101 #include <sys/queue.h> 102 #include <sys/syslog.h> 103 #include <machine/cpu.h> 104 105 #if defined(__FreeBSD__) && __FreeBSD__ >= 3 106 #include <sys/malloc.h> 107 #endif 108 109 #include <net/if.h> 110 #include <net/route.h> 111 #include <net/netisr.h> 112 #include <net/if_types.h> 113 #include <net/if_stf.h> 114 115 #include <netinet/in.h> 116 #include <netinet/in_systm.h> 117 #include <netinet/ip.h> 118 #include <netinet/ip_var.h> 119 #include <netinet/in_var.h> 120 121 #include <netinet/ip6.h> 122 #include <netinet6/ip6_var.h> 123 #include <netinet6/in6_gif.h> 124 #include <netinet6/in6_var.h> 125 #include <netinet/ip_ecn.h> 126 127 #include <netinet/ip_encap.h> 128 129 #include <machine/stdarg.h> 130 131 #include <net/net_osdep.h> 132 133 #if defined(__FreeBSD__) && __FreeBSD__ >= 4 134 #include "bpf.h" 135 #define NBPFILTER NBPF 136 #else 137 #include "bpfilter.h" 138 #endif 139 #include "stf.h" 140 #include "gif.h" /*XXX*/ 141 142 #if NBPFILTER > 0 143 #include <net/bpf.h> 144 #endif 145 146 #if NGIF > 0 147 #include <net/if_gif.h> 148 #endif 149 150 #if NSTF > 0 151 152 #define IN6_IS_ADDR_6TO4(x) (ntohs((x)->s6_addr16[0]) == 0x2002) 153 #define GET_V4(x) ((struct in_addr *)(&(x)->s6_addr16[1])) 154 155 struct stf_softc { 156 struct ifnet sc_if; /* common area */ 157 union { 158 struct route __sc_ro4; 159 struct route_in6 __sc_ro6; /* just for safety */ 160 } __sc_ro46; 161 #define sc_ro __sc_ro46.__sc_ro4 162 const struct encaptab *encap_cookie; 163 LIST_ENTRY(stf_softc) sc_list; 164 }; 165 166 LIST_HEAD(, stf_softc) stf_softc_list; 167 168 int stf_clone_create __P((struct if_clone *, int)); 169 void stf_clone_destroy __P((struct ifnet *)); 170 171 struct if_clone stf_cloner = 172 IF_CLONE_INITIALIZER("stf", stf_clone_create, stf_clone_destroy); 173 174 #if NGIF > 0 175 extern int ip_gif_ttl; /*XXX*/ 176 #else 177 static int ip_gif_ttl = 40; /*XXX*/ 178 #endif 179 180 extern struct protosw in_stf_protosw; 181 182 #ifdef __FreeBSD__ 183 void stfattach __P((void *)); 184 #else 185 void stfattach __P((int)); 186 #endif 187 static int stf_encapcheck __P((const struct mbuf *, int, int, void *)); 188 static struct in6_ifaddr *stf_getsrcifa6 __P((struct ifnet *)); 189 static int stf_output __P((struct ifnet *, struct mbuf *, struct sockaddr *, 190 struct rtentry *)); 191 static int stf_checkaddr4 __P((struct stf_softc *, struct in_addr *, 192 struct ifnet *)); 193 static int stf_checkaddr6 __P((struct stf_softc *, struct in6_addr *, 194 struct ifnet *)); 195 static void stf_rtrequest __P((int, struct rtentry *, struct rt_addrinfo *)); 196 #if defined(__FreeBSD__) && __FreeBSD__ < 3 197 static int stf_ioctl __P((struct ifnet *, int, caddr_t)); 198 #else 199 static int stf_ioctl __P((struct ifnet *, u_long, caddr_t)); 200 #endif 201 202 /* ARGSUSED */ 203 void 204 stfattach(count) 205 int count; 206 { 207 208 LIST_INIT(&stf_softc_list); 209 if_clone_attach(&stf_cloner); 210 } 211 212 int 213 stf_clone_create(ifc, unit) 214 struct if_clone *ifc; 215 int unit; 216 { 217 struct stf_softc *sc; 218 219 if (LIST_FIRST(&stf_softc_list) != NULL) { 220 /* Only one stf interface is allowed. */ 221 return (EEXIST); 222 } 223 224 sc = malloc(sizeof(struct stf_softc), M_DEVBUF, M_WAIT); 225 memset(sc, 0, sizeof(struct stf_softc)); 226 227 sprintf(sc->sc_if.if_xname, "%s%d", ifc->ifc_name, unit); 228 229 sc->encap_cookie = encap_attach_func(AF_INET, IPPROTO_IPV6, 230 stf_encapcheck, &in_stf_protosw, sc); 231 if (sc->encap_cookie == NULL) { 232 printf("%s: unable to attach encap\n", if_name(&sc->sc_if)); 233 free(sc, M_DEVBUF); 234 return (EIO); /* XXX */ 235 } 236 237 sc->sc_if.if_mtu = IPV6_MMTU; 238 sc->sc_if.if_flags = 0; 239 sc->sc_if.if_ioctl = stf_ioctl; 240 sc->sc_if.if_output = stf_output; 241 sc->sc_if.if_type = IFT_STF; 242 sc->sc_if.if_dlt = DLT_NULL; 243 #if defined(__FreeBSD__) && __FreeBSD__ >= 4 244 sc->sc_if.if_snd.ifq_maxlen = IFQ_MAXLEN; 245 #endif 246 if_attach(&sc->sc_if); 247 if_alloc_sadl(&sc->sc_if); 248 #if NBPFILTER > 0 249 bpfattach(&sc->sc_if, DLT_NULL, sizeof(u_int)); 250 #endif 251 LIST_INSERT_HEAD(&stf_softc_list, sc, sc_list); 252 return (0); 253 } 254 255 void 256 stf_clone_destroy(ifp) 257 struct ifnet *ifp; 258 { 259 struct stf_softc *sc = (void *) ifp; 260 261 LIST_REMOVE(sc, sc_list); 262 encap_detach(sc->encap_cookie); 263 #if NBPFILTER > 0 264 bpfdetach(ifp); 265 #endif 266 if_detach(ifp); 267 free(sc, M_DEVBUF); 268 } 269 270 #ifdef __FreeBSD__ 271 PSEUDO_SET(stfattach, if_stf); 272 #endif 273 274 static int 275 stf_encapcheck(m, off, proto, arg) 276 const struct mbuf *m; 277 int off; 278 int proto; 279 void *arg; 280 { 281 struct ip ip; 282 struct in6_ifaddr *ia6; 283 struct stf_softc *sc; 284 struct in_addr a, b; 285 286 sc = (struct stf_softc *)arg; 287 if (sc == NULL) 288 return 0; 289 290 if ((sc->sc_if.if_flags & IFF_UP) == 0) 291 return 0; 292 293 /* IFF_LINK0 means "no decapsulation" */ 294 if ((sc->sc_if.if_flags & IFF_LINK0) != 0) 295 return 0; 296 297 if (proto != IPPROTO_IPV6) 298 return 0; 299 300 /* LINTED const cast */ 301 m_copydata((struct mbuf *)m, 0, sizeof(ip), (caddr_t)&ip); 302 303 if (ip.ip_v != 4) 304 return 0; 305 306 ia6 = stf_getsrcifa6(&sc->sc_if); 307 if (ia6 == NULL) 308 return 0; 309 310 /* 311 * check if IPv4 dst matches the IPv4 address derived from the 312 * local 6to4 address. 313 * success on: dst = 10.1.1.1, ia6->ia_addr = 2002:0a01:0101:... 314 */ 315 if (bcmp(GET_V4(&ia6->ia_addr.sin6_addr), &ip.ip_dst, 316 sizeof(ip.ip_dst)) != 0) 317 return 0; 318 319 /* 320 * check if IPv4 src matches the IPv4 address derived from the 321 * local 6to4 address masked by prefixmask. 322 * success on: src = 10.1.1.1, ia6->ia_addr = 2002:0a00:.../24 323 * fail on: src = 10.1.1.1, ia6->ia_addr = 2002:0b00:.../24 324 */ 325 memset(&a, 0, sizeof(a)); 326 a.s_addr = GET_V4(&ia6->ia_addr.sin6_addr)->s_addr; 327 a.s_addr &= GET_V4(&ia6->ia_prefixmask.sin6_addr)->s_addr; 328 b = ip.ip_src; 329 b.s_addr &= GET_V4(&ia6->ia_prefixmask.sin6_addr)->s_addr; 330 if (a.s_addr != b.s_addr) 331 return 0; 332 333 /* stf interface makes single side match only */ 334 return 32; 335 } 336 337 static struct in6_ifaddr * 338 stf_getsrcifa6(ifp) 339 struct ifnet *ifp; 340 { 341 struct ifaddr *ia; 342 struct in_ifaddr *ia4; 343 struct sockaddr_in6 *sin6; 344 struct in_addr in; 345 346 #if defined(__bsdi__) || (defined(__FreeBSD__) && __FreeBSD__ < 3) 347 for (ia = ifp->if_addrlist; ia; ia = ia->ifa_next) 348 #else 349 TAILQ_FOREACH(ia, &ifp->if_addrlist, ifa_list) 350 #endif 351 { 352 if (ia->ifa_addr == NULL) 353 continue; 354 if (ia->ifa_addr->sa_family != AF_INET6) 355 continue; 356 sin6 = (struct sockaddr_in6 *)ia->ifa_addr; 357 if (!IN6_IS_ADDR_6TO4(&sin6->sin6_addr)) 358 continue; 359 360 bcopy(GET_V4(&sin6->sin6_addr), &in, sizeof(in)); 361 #ifdef __NetBSD__ 362 INADDR_TO_IA(in, ia4); 363 #else 364 #ifdef __OpenBSD__ 365 for (ia4 = TAILQ_FIRST(&in_ifaddr); 366 ia4; 367 ia4 = TAILQ_NEXT(ia4, ia_list)) 368 #elif defined(__FreeBSD__) && __FreeBSD__ >= 3 369 for (ia4 = TAILQ_FIRST(&in_ifaddrhead); 370 ia4; 371 ia4 = TAILQ_NEXT(ia4, ia_link)) 372 #else 373 for (ia4 = in_ifaddr; ia4 != NULL; ia4 = ia4->ia_next) 374 #endif 375 { 376 if (ia4->ia_addr.sin_addr.s_addr == in.s_addr) 377 break; 378 } 379 #endif 380 if (ia4 == NULL) 381 continue; 382 383 return (struct in6_ifaddr *)ia; 384 } 385 386 return NULL; 387 } 388 389 static int 390 stf_output(ifp, m, dst, rt) 391 struct ifnet *ifp; 392 struct mbuf *m; 393 struct sockaddr *dst; 394 struct rtentry *rt; 395 { 396 struct stf_softc *sc; 397 struct sockaddr_in6 *dst6; 398 struct in_addr *in4; 399 struct sockaddr_in *dst4; 400 u_int8_t tos; 401 struct ip *ip; 402 struct ip6_hdr *ip6; 403 struct in6_ifaddr *ia6; 404 405 sc = (struct stf_softc*)ifp; 406 dst6 = (struct sockaddr_in6 *)dst; 407 408 /* just in case */ 409 if ((ifp->if_flags & IFF_UP) == 0) { 410 m_freem(m); 411 return ENETDOWN; 412 } 413 414 /* 415 * If we don't have an ip4 address that match my inner ip6 address, 416 * we shouldn't generate output. Without this check, we'll end up 417 * using wrong IPv4 source. 418 */ 419 ia6 = stf_getsrcifa6(ifp); 420 if (ia6 == NULL) { 421 m_freem(m); 422 return ENETDOWN; 423 } 424 425 if (m->m_len < sizeof(*ip6)) { 426 m = m_pullup(m, sizeof(*ip6)); 427 if (!m) 428 return ENOBUFS; 429 } 430 ip6 = mtod(m, struct ip6_hdr *); 431 tos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; 432 433 /* 434 * Pickup the right outer dst addr from the list of candidates. 435 * ip6_dst has priority as it may be able to give us shorter IPv4 hops. 436 */ 437 if (IN6_IS_ADDR_6TO4(&ip6->ip6_dst)) 438 in4 = GET_V4(&ip6->ip6_dst); 439 else if (IN6_IS_ADDR_6TO4(&dst6->sin6_addr)) 440 in4 = GET_V4(&dst6->sin6_addr); 441 else { 442 m_freem(m); 443 return ENETUNREACH; 444 } 445 446 #if NBPFILTER > 0 447 if (ifp->if_bpf) { 448 /* 449 * We need to prepend the address family as 450 * a four byte field. Cons up a dummy header 451 * to pacify bpf. This is safe because bpf 452 * will only read from the mbuf (i.e., it won't 453 * try to free it or keep a pointer a to it). 454 */ 455 struct mbuf m0; 456 u_int32_t af = AF_INET6; 457 458 m0.m_next = m; 459 m0.m_len = 4; 460 m0.m_data = (char *)⁡ 461 462 #ifdef HAVE_OLD_BPF 463 bpf_mtap(ifp, &m0); 464 #else 465 bpf_mtap(ifp->if_bpf, &m0); 466 #endif 467 } 468 #endif /*NBPFILTER > 0*/ 469 470 M_PREPEND(m, sizeof(struct ip), M_DONTWAIT); 471 if (m && m->m_len < sizeof(struct ip)) 472 m = m_pullup(m, sizeof(struct ip)); 473 if (m == NULL) 474 return ENOBUFS; 475 ip = mtod(m, struct ip *); 476 477 memset(ip, 0, sizeof(*ip)); 478 479 bcopy(GET_V4(&((struct sockaddr_in6 *)&ia6->ia_addr)->sin6_addr), 480 &ip->ip_src, sizeof(ip->ip_src)); 481 bcopy(in4, &ip->ip_dst, sizeof(ip->ip_dst)); 482 ip->ip_p = IPPROTO_IPV6; 483 ip->ip_ttl = ip_gif_ttl; /*XXX*/ 484 ip->ip_len = m->m_pkthdr.len; /*host order*/ 485 if (ifp->if_flags & IFF_LINK1) 486 ip_ecn_ingress(ECN_ALLOWED, &ip->ip_tos, &tos); 487 else 488 ip_ecn_ingress(ECN_NOCARE, &ip->ip_tos, &tos); 489 490 dst4 = (struct sockaddr_in *)&sc->sc_ro.ro_dst; 491 if (dst4->sin_family != AF_INET || 492 bcmp(&dst4->sin_addr, &ip->ip_dst, sizeof(ip->ip_dst)) != 0) { 493 /* cache route doesn't match */ 494 dst4->sin_family = AF_INET; 495 dst4->sin_len = sizeof(struct sockaddr_in); 496 bcopy(&ip->ip_dst, &dst4->sin_addr, sizeof(dst4->sin_addr)); 497 if (sc->sc_ro.ro_rt) { 498 RTFREE(sc->sc_ro.ro_rt); 499 sc->sc_ro.ro_rt = NULL; 500 } 501 } 502 503 if (sc->sc_ro.ro_rt == NULL) { 504 rtalloc(&sc->sc_ro); 505 if (sc->sc_ro.ro_rt == NULL) { 506 m_freem(m); 507 return ENETUNREACH; 508 } 509 } 510 511 #ifndef __OpenBSD__ 512 return ip_output(m, NULL, &sc->sc_ro, 0, NULL); 513 #else 514 return ip_output(m, NULL, &sc->sc_ro, 0, NULL, NULL); 515 #endif 516 } 517 518 static int 519 stf_checkaddr4(sc, in, inifp) 520 struct stf_softc *sc; 521 struct in_addr *in; 522 struct ifnet *inifp; /* incoming interface */ 523 { 524 struct in_ifaddr *ia4; 525 526 /* 527 * reject packets with the following address: 528 * 224.0.0.0/4 0.0.0.0/8 127.0.0.0/8 255.0.0.0/8 529 */ 530 if (IN_MULTICAST(in->s_addr)) 531 return -1; 532 switch ((ntohl(in->s_addr) & 0xff000000) >> 24) { 533 case 0: case 127: case 255: 534 return -1; 535 } 536 537 /* 538 * reject packets with broadcast 539 */ 540 #if defined(__OpenBSD__) || defined(__NetBSD__) 541 TAILQ_FOREACH(ia4, &in_ifaddr, ia_list) 542 #elif defined(__FreeBSD__) && __FreeBSD__ >= 3 543 for (ia4 = TAILQ_FIRST(&in_ifaddrhead); 544 ia4; 545 ia4 = TAILQ_NEXT(ia4, ia_link)) 546 #else 547 for (ia4 = in_ifaddr; ia4 != NULL; ia4 = ia4->ia_next) 548 #endif 549 { 550 if ((ia4->ia_ifa.ifa_ifp->if_flags & IFF_BROADCAST) == 0) 551 continue; 552 if (in->s_addr == ia4->ia_broadaddr.sin_addr.s_addr) 553 return -1; 554 } 555 556 /* 557 * perform ingress filter 558 */ 559 if (sc && (sc->sc_if.if_flags & IFF_LINK2) == 0 && inifp) { 560 struct sockaddr_in sin; 561 struct rtentry *rt; 562 563 memset(&sin, 0, sizeof(sin)); 564 sin.sin_family = AF_INET; 565 sin.sin_len = sizeof(struct sockaddr_in); 566 sin.sin_addr = *in; 567 #ifdef __FreeBSD__ 568 rt = rtalloc1((struct sockaddr *)&sin, 0, 0UL); 569 #else 570 rt = rtalloc1((struct sockaddr *)&sin, 0); 571 #endif 572 if (!rt || rt->rt_ifp != inifp) { 573 #if 0 574 log(LOG_WARNING, "%s: packet from 0x%x dropped " 575 "due to ingress filter\n", if_name(&sc->sc_if), 576 (u_int32_t)ntohl(sin.sin_addr.s_addr)); 577 #endif 578 if (rt) 579 rtfree(rt); 580 return -1; 581 } 582 rtfree(rt); 583 } 584 585 return 0; 586 } 587 588 static int 589 stf_checkaddr6(sc, in6, inifp) 590 struct stf_softc *sc; 591 struct in6_addr *in6; 592 struct ifnet *inifp; /* incoming interface */ 593 { 594 /* 595 * check 6to4 addresses 596 */ 597 if (IN6_IS_ADDR_6TO4(in6)) 598 return stf_checkaddr4(sc, GET_V4(in6), inifp); 599 600 /* 601 * reject anything that look suspicious. the test is implemented 602 * in ip6_input too, but we check here as well to 603 * (1) reject bad packets earlier, and 604 * (2) to be safe against future ip6_input change. 605 */ 606 if (IN6_IS_ADDR_V4COMPAT(in6) || IN6_IS_ADDR_V4MAPPED(in6)) 607 return -1; 608 609 return 0; 610 } 611 612 void 613 #if __STDC__ 614 in_stf_input(struct mbuf *m, ...) 615 #else 616 in_stf_input(m, va_alist) 617 struct mbuf *m; 618 #endif 619 { 620 int off, proto; 621 struct stf_softc *sc; 622 struct ip *ip; 623 struct ip6_hdr *ip6; 624 u_int8_t otos, itos; 625 int s, isr; 626 struct ifqueue *ifq = NULL; 627 struct ifnet *ifp; 628 va_list ap; 629 630 va_start(ap, m); 631 off = va_arg(ap, int); 632 proto = va_arg(ap, int); 633 va_end(ap); 634 635 if (proto != IPPROTO_IPV6) { 636 m_freem(m); 637 return; 638 } 639 640 ip = mtod(m, struct ip *); 641 642 sc = (struct stf_softc *)encap_getarg(m); 643 644 if (sc == NULL || (sc->sc_if.if_flags & IFF_UP) == 0) { 645 m_freem(m); 646 return; 647 } 648 649 ifp = &sc->sc_if; 650 651 /* 652 * perform sanity check against outer src/dst. 653 * for source, perform ingress filter as well. 654 */ 655 if (stf_checkaddr4(sc, &ip->ip_dst, NULL) < 0 || 656 stf_checkaddr4(sc, &ip->ip_src, m->m_pkthdr.rcvif) < 0) { 657 m_freem(m); 658 return; 659 } 660 661 otos = ip->ip_tos; 662 m_adj(m, off); 663 664 if (m->m_len < sizeof(*ip6)) { 665 m = m_pullup(m, sizeof(*ip6)); 666 if (!m) 667 return; 668 } 669 ip6 = mtod(m, struct ip6_hdr *); 670 671 /* 672 * perform sanity check against inner src/dst. 673 * for source, perform ingress filter as well. 674 */ 675 if (stf_checkaddr6(sc, &ip6->ip6_dst, NULL) < 0 || 676 stf_checkaddr6(sc, &ip6->ip6_src, m->m_pkthdr.rcvif) < 0) { 677 m_freem(m); 678 return; 679 } 680 681 itos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; 682 if ((ifp->if_flags & IFF_LINK1) != 0) 683 ip_ecn_egress(ECN_ALLOWED, &otos, &itos); 684 else 685 ip_ecn_egress(ECN_NOCARE, &otos, &itos); 686 ip6->ip6_flow &= ~htonl(0xff << 20); 687 ip6->ip6_flow |= htonl((u_int32_t)itos << 20); 688 689 m->m_pkthdr.rcvif = ifp; 690 691 #if NBPFILTER > 0 692 if (ifp->if_bpf) { 693 /* 694 * We need to prepend the address family as 695 * a four byte field. Cons up a dummy header 696 * to pacify bpf. This is safe because bpf 697 * will only read from the mbuf (i.e., it won't 698 * try to free it or keep a pointer a to it). 699 */ 700 struct mbuf m0; 701 u_int32_t af = AF_INET6; 702 703 m0.m_next = m; 704 m0.m_len = 4; 705 m0.m_data = (char *)⁡ 706 707 #ifdef HAVE_OLD_BPF 708 bpf_mtap(ifp, &m0); 709 #else 710 bpf_mtap(ifp->if_bpf, &m0); 711 #endif 712 } 713 #endif /*NBPFILTER > 0*/ 714 715 /* 716 * Put the packet to the network layer input queue according to the 717 * specified address family. 718 * See net/if_gif.c for possible issues with packet processing 719 * reorder due to extra queueing. 720 */ 721 ifq = &ip6intrq; 722 isr = NETISR_IPV6; 723 724 s = splnet(); 725 if (IF_QFULL(ifq)) { 726 IF_DROP(ifq); /* update statistics */ 727 m_freem(m); 728 splx(s); 729 return; 730 } 731 IF_ENQUEUE(ifq, m); 732 schednetisr(isr); 733 ifp->if_ipackets++; 734 ifp->if_ibytes += m->m_pkthdr.len; 735 splx(s); 736 } 737 738 /* ARGSUSED */ 739 static void 740 stf_rtrequest(cmd, rt, info) 741 int cmd; 742 struct rtentry *rt; 743 struct rt_addrinfo *info; 744 { 745 746 if (rt) 747 rt->rt_rmx.rmx_mtu = IPV6_MMTU; 748 } 749 750 static int 751 stf_ioctl(ifp, cmd, data) 752 struct ifnet *ifp; 753 #if defined(__FreeBSD__) && __FreeBSD__ < 3 754 int cmd; 755 #else 756 u_long cmd; 757 #endif 758 caddr_t data; 759 { 760 struct ifaddr *ifa; 761 struct ifreq *ifr; 762 struct sockaddr_in6 *sin6; 763 int error; 764 765 error = 0; 766 switch (cmd) { 767 case SIOCSIFADDR: 768 ifa = (struct ifaddr *)data; 769 if (ifa == NULL || ifa->ifa_addr->sa_family != AF_INET6) { 770 error = EAFNOSUPPORT; 771 break; 772 } 773 sin6 = (struct sockaddr_in6 *)ifa->ifa_addr; 774 if (IN6_IS_ADDR_6TO4(&sin6->sin6_addr)) { 775 ifa->ifa_rtrequest = stf_rtrequest; 776 ifp->if_flags |= IFF_UP; 777 } else 778 error = EINVAL; 779 break; 780 781 case SIOCADDMULTI: 782 case SIOCDELMULTI: 783 ifr = (struct ifreq *)data; 784 if (ifr && ifr->ifr_addr.sa_family == AF_INET6) 785 ; 786 else 787 error = EAFNOSUPPORT; 788 break; 789 790 default: 791 error = EINVAL; 792 break; 793 } 794 795 return error; 796 } 797 798 #endif /* NSTF > 0 */ 799
Indexes created Mon Sep 29 21:09:56 GMT 2025