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