1 /* $NetBSD: if_stf.c,v 1.32 2002/11/17 19:29:31 itojun 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 1.32 2002/11/17 19:29:31 itojun 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 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 sprintf(sc->sc_if.if_xname, "%s%d", ifc->ifc_name, unit); 205 206 sc->encap_cookie = encap_attach_func(AF_INET, IPPROTO_IPV6, 207 stf_encapcheck, &in_stf_protosw, sc); 208 if (sc->encap_cookie == NULL) { 209 printf("%s: unable to attach encap\n", if_name(&sc->sc_if)); 210 free(sc, M_DEVBUF); 211 return (EIO); /* XXX */ 212 } 213 214 sc->sc_if.if_mtu = IPV6_MMTU; 215 sc->sc_if.if_flags = 0; 216 sc->sc_if.if_ioctl = stf_ioctl; 217 sc->sc_if.if_output = stf_output; 218 sc->sc_if.if_type = IFT_STF; 219 sc->sc_if.if_dlt = DLT_NULL; 220 if_attach(&sc->sc_if); 221 if_alloc_sadl(&sc->sc_if); 222 #if NBPFILTER > 0 223 bpfattach(&sc->sc_if, DLT_NULL, sizeof(u_int)); 224 #endif 225 LIST_INSERT_HEAD(&stf_softc_list, sc, sc_list); 226 return (0); 227 } 228 229 void 230 stf_clone_destroy(ifp) 231 struct ifnet *ifp; 232 { 233 struct stf_softc *sc = (void *) ifp; 234 235 LIST_REMOVE(sc, sc_list); 236 encap_detach(sc->encap_cookie); 237 #if NBPFILTER > 0 238 bpfdetach(ifp); 239 #endif 240 if_detach(ifp); 241 free(sc, M_DEVBUF); 242 } 243 244 static int 245 stf_encapcheck(m, off, proto, arg) 246 const struct mbuf *m; 247 int off; 248 int proto; 249 void *arg; 250 { 251 struct ip ip; 252 struct in6_ifaddr *ia6; 253 struct stf_softc *sc; 254 struct in_addr a, b; 255 256 sc = (struct stf_softc *)arg; 257 if (sc == NULL) 258 return 0; 259 260 if ((sc->sc_if.if_flags & IFF_UP) == 0) 261 return 0; 262 263 /* IFF_LINK0 means "no decapsulation" */ 264 if ((sc->sc_if.if_flags & IFF_LINK0) != 0) 265 return 0; 266 267 if (proto != IPPROTO_IPV6) 268 return 0; 269 270 /* LINTED const cast */ 271 m_copydata((struct mbuf *)m, 0, sizeof(ip), (caddr_t)&ip); 272 273 if (ip.ip_v != 4) 274 return 0; 275 276 ia6 = stf_getsrcifa6(&sc->sc_if); 277 if (ia6 == NULL) 278 return 0; 279 280 /* 281 * check if IPv4 dst matches the IPv4 address derived from the 282 * local 6to4 address. 283 * success on: dst = 10.1.1.1, ia6->ia_addr = 2002:0a01:0101:... 284 */ 285 if (bcmp(GET_V4(&ia6->ia_addr.sin6_addr), &ip.ip_dst, 286 sizeof(ip.ip_dst)) != 0) 287 return 0; 288 289 /* 290 * check if IPv4 src matches the IPv4 address derived from the 291 * local 6to4 address masked by prefixmask. 292 * success on: src = 10.1.1.1, ia6->ia_addr = 2002:0a00:.../24 293 * fail on: src = 10.1.1.1, ia6->ia_addr = 2002:0b00:.../24 294 */ 295 memset(&a, 0, sizeof(a)); 296 a.s_addr = GET_V4(&ia6->ia_addr.sin6_addr)->s_addr; 297 a.s_addr &= GET_V4(&ia6->ia_prefixmask.sin6_addr)->s_addr; 298 b = ip.ip_src; 299 b.s_addr &= GET_V4(&ia6->ia_prefixmask.sin6_addr)->s_addr; 300 if (a.s_addr != b.s_addr) 301 return 0; 302 303 /* stf interface makes single side match only */ 304 return 32; 305 } 306 307 static struct in6_ifaddr * 308 stf_getsrcifa6(ifp) 309 struct ifnet *ifp; 310 { 311 struct ifaddr *ia; 312 struct in_ifaddr *ia4; 313 struct sockaddr_in6 *sin6; 314 struct in_addr in; 315 316 TAILQ_FOREACH(ia, &ifp->if_addrlist, ifa_list) 317 { 318 if (ia->ifa_addr == NULL) 319 continue; 320 if (ia->ifa_addr->sa_family != AF_INET6) 321 continue; 322 sin6 = (struct sockaddr_in6 *)ia->ifa_addr; 323 if (!IN6_IS_ADDR_6TO4(&sin6->sin6_addr)) 324 continue; 325 326 bcopy(GET_V4(&sin6->sin6_addr), &in, sizeof(in)); 327 INADDR_TO_IA(in, ia4); 328 if (ia4 == NULL) 329 continue; 330 331 return (struct in6_ifaddr *)ia; 332 } 333 334 return NULL; 335 } 336 337 static int 338 stf_output(ifp, m, dst, rt) 339 struct ifnet *ifp; 340 struct mbuf *m; 341 struct sockaddr *dst; 342 struct rtentry *rt; 343 { 344 struct stf_softc *sc; 345 struct sockaddr_in6 *dst6; 346 struct in_addr *in4; 347 struct sockaddr_in *dst4; 348 u_int8_t tos; 349 struct ip *ip; 350 struct ip6_hdr *ip6; 351 struct in6_ifaddr *ia6; 352 353 sc = (struct stf_softc*)ifp; 354 dst6 = (struct sockaddr_in6 *)dst; 355 356 /* just in case */ 357 if ((ifp->if_flags & IFF_UP) == 0) { 358 m_freem(m); 359 return ENETDOWN; 360 } 361 362 /* 363 * If we don't have an ip4 address that match my inner ip6 address, 364 * we shouldn't generate output. Without this check, we'll end up 365 * using wrong IPv4 source. 366 */ 367 ia6 = stf_getsrcifa6(ifp); 368 if (ia6 == NULL) { 369 m_freem(m); 370 ifp->if_oerrors++; 371 return ENETDOWN; 372 } 373 374 if (m->m_len < sizeof(*ip6)) { 375 m = m_pullup(m, sizeof(*ip6)); 376 if (m == NULL) { 377 ifp->if_oerrors++; 378 return ENOBUFS; 379 } 380 } 381 ip6 = mtod(m, struct ip6_hdr *); 382 tos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; 383 384 /* 385 * Pickup the right outer dst addr from the list of candidates. 386 * ip6_dst has priority as it may be able to give us shorter IPv4 hops. 387 */ 388 if (IN6_IS_ADDR_6TO4(&ip6->ip6_dst)) 389 in4 = GET_V4(&ip6->ip6_dst); 390 else if (IN6_IS_ADDR_6TO4(&dst6->sin6_addr)) 391 in4 = GET_V4(&dst6->sin6_addr); 392 else { 393 m_freem(m); 394 ifp->if_oerrors++; 395 return ENETUNREACH; 396 } 397 398 #if NBPFILTER > 0 399 if (ifp->if_bpf) { 400 /* 401 * We need to prepend the address family as 402 * a four byte field. Cons up a dummy header 403 * to pacify bpf. This is safe because bpf 404 * will only read from the mbuf (i.e., it won't 405 * try to free it or keep a pointer a to it). 406 */ 407 struct mbuf m0; 408 u_int32_t af = AF_INET6; 409 410 m0.m_next = m; 411 m0.m_len = 4; 412 m0.m_data = (char *)⁡ 413 414 #ifdef HAVE_OLD_BPF 415 bpf_mtap(ifp, &m0); 416 #else 417 bpf_mtap(ifp->if_bpf, &m0); 418 #endif 419 } 420 #endif /*NBPFILTER > 0*/ 421 422 M_PREPEND(m, sizeof(struct ip), M_DONTWAIT); 423 if (m && m->m_len < sizeof(struct ip)) 424 m = m_pullup(m, sizeof(struct ip)); 425 if (m == NULL) { 426 ifp->if_oerrors++; 427 return ENOBUFS; 428 } 429 ip = mtod(m, struct ip *); 430 431 memset(ip, 0, sizeof(*ip)); 432 433 bcopy(GET_V4(&((struct sockaddr_in6 *)&ia6->ia_addr)->sin6_addr), 434 &ip->ip_src, sizeof(ip->ip_src)); 435 bcopy(in4, &ip->ip_dst, sizeof(ip->ip_dst)); 436 ip->ip_p = IPPROTO_IPV6; 437 ip->ip_ttl = ip_gif_ttl; /*XXX*/ 438 ip->ip_len = htons(m->m_pkthdr.len); 439 if (ifp->if_flags & IFF_LINK1) 440 ip_ecn_ingress(ECN_ALLOWED, &ip->ip_tos, &tos); 441 else 442 ip_ecn_ingress(ECN_NOCARE, &ip->ip_tos, &tos); 443 444 dst4 = (struct sockaddr_in *)&sc->sc_ro.ro_dst; 445 if (dst4->sin_family != AF_INET || 446 bcmp(&dst4->sin_addr, &ip->ip_dst, sizeof(ip->ip_dst)) != 0) { 447 /* cache route doesn't match */ 448 dst4->sin_family = AF_INET; 449 dst4->sin_len = sizeof(struct sockaddr_in); 450 bcopy(&ip->ip_dst, &dst4->sin_addr, sizeof(dst4->sin_addr)); 451 if (sc->sc_ro.ro_rt) { 452 RTFREE(sc->sc_ro.ro_rt); 453 sc->sc_ro.ro_rt = NULL; 454 } 455 } 456 457 if (sc->sc_ro.ro_rt == NULL) { 458 rtalloc(&sc->sc_ro); 459 if (sc->sc_ro.ro_rt == NULL) { 460 m_freem(m); 461 ifp->if_oerrors++; 462 return ENETUNREACH; 463 } 464 } 465 466 ifp->if_opackets++; 467 return ip_output(m, NULL, &sc->sc_ro, 0, NULL); 468 } 469 470 static int 471 isrfc1918addr(in) 472 struct in_addr *in; 473 { 474 /* 475 * returns 1 if private address range: 476 * 10.0.0.0/8 172.16.0.0/12 192.168.0.0/16 477 */ 478 if ((ntohl(in->s_addr) & 0xff000000) >> 24 == 10 || 479 (ntohl(in->s_addr) & 0xfff00000) >> 16 == 172 * 256 + 16 || 480 (ntohl(in->s_addr) & 0xffff0000) >> 16 == 192 * 256 + 168) 481 return 1; 482 483 return 0; 484 } 485 486 static int 487 stf_checkaddr4(sc, in, inifp) 488 struct stf_softc *sc; 489 struct in_addr *in; 490 struct ifnet *inifp; /* incoming interface */ 491 { 492 struct in_ifaddr *ia4; 493 494 /* 495 * reject packets with the following address: 496 * 224.0.0.0/4 0.0.0.0/8 127.0.0.0/8 255.0.0.0/8 497 */ 498 if (IN_MULTICAST(in->s_addr)) 499 return -1; 500 switch ((ntohl(in->s_addr) & 0xff000000) >> 24) { 501 case 0: case 127: case 255: 502 return -1; 503 } 504 505 /* 506 * reject packets with private address range. 507 * (requirement from RFC3056 section 2 1st paragraph) 508 */ 509 if (isrfc1918addr(in)) 510 return -1; 511 512 /* 513 * reject packet with IPv4 link-local (169.254.0.0/16), 514 * as suggested in draft-savola-v6ops-6to4-security-00.txt 515 */ 516 if (((ntohl(in->s_addr) & 0xff000000) >> 24) == 169 && 517 ((ntohl(in->s_addr) & 0x00ff0000) >> 16) == 254) 518 return -1; 519 520 /* 521 * reject packets with broadcast 522 */ 523 TAILQ_FOREACH(ia4, &in_ifaddr, ia_list) 524 { 525 if ((ia4->ia_ifa.ifa_ifp->if_flags & IFF_BROADCAST) == 0) 526 continue; 527 if (in->s_addr == ia4->ia_broadaddr.sin_addr.s_addr) 528 return -1; 529 } 530 531 /* 532 * perform ingress filter 533 */ 534 if (sc && (sc->sc_if.if_flags & IFF_LINK2) == 0 && inifp) { 535 struct sockaddr_in sin; 536 struct rtentry *rt; 537 538 memset(&sin, 0, sizeof(sin)); 539 sin.sin_family = AF_INET; 540 sin.sin_len = sizeof(struct sockaddr_in); 541 sin.sin_addr = *in; 542 rt = rtalloc1((struct sockaddr *)&sin, 0); 543 if (!rt || rt->rt_ifp != inifp) { 544 #if 0 545 log(LOG_WARNING, "%s: packet from 0x%x dropped " 546 "due to ingress filter\n", if_name(&sc->sc_if), 547 (u_int32_t)ntohl(sin.sin_addr.s_addr)); 548 #endif 549 if (rt) 550 rtfree(rt); 551 return -1; 552 } 553 rtfree(rt); 554 } 555 556 return 0; 557 } 558 559 static int 560 stf_checkaddr6(sc, in6, inifp) 561 struct stf_softc *sc; 562 struct in6_addr *in6; 563 struct ifnet *inifp; /* incoming interface */ 564 { 565 566 /* 567 * check 6to4 addresses 568 */ 569 if (IN6_IS_ADDR_6TO4(in6)) 570 return stf_checkaddr4(sc, GET_V4(in6), inifp); 571 572 /* 573 * reject anything that look suspicious. the test is implemented 574 * in ip6_input too, but we check here as well to 575 * (1) reject bad packets earlier, and 576 * (2) to be safe against future ip6_input change. 577 */ 578 if (IN6_IS_ADDR_V4COMPAT(in6) || IN6_IS_ADDR_V4MAPPED(in6)) 579 return -1; 580 581 /* 582 * reject link-local and site-local unicast 583 * as suggested in draft-savola-v6ops-6to4-security-00.txt 584 */ 585 if (IN6_IS_ADDR_LINKLOCAL(in6) || IN6_IS_ADDR_SITELOCAL(in6)) 586 return -1; 587 588 /* 589 * reject node-local and link-local multicast 590 * as suggested in draft-savola-v6ops-6to4-security-00.txt 591 */ 592 if (IN6_IS_ADDR_MC_NODELOCAL(in6) || IN6_IS_ADDR_MC_LINKLOCAL(in6)) 593 return -1; 594 595 return 0; 596 } 597 598 void 599 #if __STDC__ 600 in_stf_input(struct mbuf *m, ...) 601 #else 602 in_stf_input(m, va_alist) 603 struct mbuf *m; 604 #endif 605 { 606 int off, proto; 607 struct stf_softc *sc; 608 struct ip *ip; 609 struct ip6_hdr *ip6; 610 u_int8_t otos, itos; 611 int s, isr; 612 struct ifqueue *ifq = NULL; 613 struct ifnet *ifp; 614 va_list ap; 615 616 va_start(ap, m); 617 off = va_arg(ap, int); 618 proto = va_arg(ap, int); 619 va_end(ap); 620 621 if (proto != IPPROTO_IPV6) { 622 m_freem(m); 623 return; 624 } 625 626 ip = mtod(m, struct ip *); 627 628 sc = (struct stf_softc *)encap_getarg(m); 629 630 if (sc == NULL || (sc->sc_if.if_flags & IFF_UP) == 0) { 631 m_freem(m); 632 return; 633 } 634 635 ifp = &sc->sc_if; 636 637 /* 638 * perform sanity check against outer src/dst. 639 * for source, perform ingress filter as well. 640 */ 641 if (stf_checkaddr4(sc, &ip->ip_dst, NULL) < 0 || 642 stf_checkaddr4(sc, &ip->ip_src, m->m_pkthdr.rcvif) < 0) { 643 m_freem(m); 644 return; 645 } 646 647 otos = ip->ip_tos; 648 m_adj(m, off); 649 650 if (m->m_len < sizeof(*ip6)) { 651 m = m_pullup(m, sizeof(*ip6)); 652 if (!m) 653 return; 654 } 655 ip6 = mtod(m, struct ip6_hdr *); 656 657 /* 658 * perform sanity check against inner src/dst. 659 * for source, perform ingress filter as well. 660 */ 661 if (stf_checkaddr6(sc, &ip6->ip6_dst, NULL) < 0 || 662 stf_checkaddr6(sc, &ip6->ip6_src, m->m_pkthdr.rcvif) < 0) { 663 m_freem(m); 664 return; 665 } 666 667 itos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; 668 if ((ifp->if_flags & IFF_LINK1) != 0) 669 ip_ecn_egress(ECN_ALLOWED, &otos, &itos); 670 else 671 ip_ecn_egress(ECN_NOCARE, &otos, &itos); 672 ip6->ip6_flow &= ~htonl(0xff << 20); 673 ip6->ip6_flow |= htonl((u_int32_t)itos << 20); 674 675 m->m_pkthdr.rcvif = ifp; 676 677 #if NBPFILTER > 0 678 if (ifp->if_bpf) { 679 /* 680 * We need to prepend the address family as 681 * a four byte field. Cons up a dummy header 682 * to pacify bpf. This is safe because bpf 683 * will only read from the mbuf (i.e., it won't 684 * try to free it or keep a pointer a to it). 685 */ 686 struct mbuf m0; 687 u_int32_t af = AF_INET6; 688 689 m0.m_next = m; 690 m0.m_len = 4; 691 m0.m_data = (char *)⁡ 692 693 #ifdef HAVE_OLD_BPF 694 bpf_mtap(ifp, &m0); 695 #else 696 bpf_mtap(ifp->if_bpf, &m0); 697 #endif 698 } 699 #endif /*NBPFILTER > 0*/ 700 701 /* 702 * Put the packet to the network layer input queue according to the 703 * specified address family. 704 * See net/if_gif.c for possible issues with packet processing 705 * reorder due to extra queueing. 706 */ 707 ifq = &ip6intrq; 708 isr = NETISR_IPV6; 709 710 s = splnet(); 711 if (IF_QFULL(ifq)) { 712 IF_DROP(ifq); /* update statistics */ 713 m_freem(m); 714 splx(s); 715 return; 716 } 717 IF_ENQUEUE(ifq, m); 718 schednetisr(isr); 719 ifp->if_ipackets++; 720 ifp->if_ibytes += m->m_pkthdr.len; 721 splx(s); 722 } 723 724 /* ARGSUSED */ 725 static void 726 stf_rtrequest(cmd, rt, info) 727 int cmd; 728 struct rtentry *rt; 729 struct rt_addrinfo *info; 730 { 731 732 if (rt) 733 rt->rt_rmx.rmx_mtu = IPV6_MMTU; 734 } 735 736 static int 737 stf_ioctl(ifp, cmd, data) 738 struct ifnet *ifp; 739 u_long cmd; 740 caddr_t data; 741 { 742 struct ifaddr *ifa; 743 struct ifreq *ifr; 744 struct sockaddr_in6 *sin6; 745 int error; 746 747 error = 0; 748 switch (cmd) { 749 case SIOCSIFADDR: 750 ifa = (struct ifaddr *)data; 751 if (ifa == NULL || ifa->ifa_addr->sa_family != AF_INET6) { 752 error = EAFNOSUPPORT; 753 break; 754 } 755 sin6 = (struct sockaddr_in6 *)ifa->ifa_addr; 756 if (IN6_IS_ADDR_6TO4(&sin6->sin6_addr) && 757 !isrfc1918addr(GET_V4(&sin6->sin6_addr))) { 758 ifa->ifa_rtrequest = stf_rtrequest; 759 ifp->if_flags |= IFF_UP; 760 } else 761 error = EINVAL; 762 break; 763 764 case SIOCADDMULTI: 765 case SIOCDELMULTI: 766 ifr = (struct ifreq *)data; 767 if (ifr && ifr->ifr_addr.sa_family == AF_INET6) 768 ; 769 else 770 error = EAFNOSUPPORT; 771 break; 772 773 default: 774 error = EINVAL; 775 break; 776 } 777 778 return error; 779 } 780