if_stf.c revision 78701
1/* $FreeBSD: head/sys/net/if_stf.c 78701 2001-06-24 14:52:55Z ume $ */ 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/ip_var.h> 102#include <netinet/in_var.h> 103 104#include <netinet/ip6.h> 105#include <netinet6/ip6_var.h> 106#include <netinet6/in6_gif.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 "bpf.h" 117#define NBPFILTER NBPF 118#include "stf.h" 119#include "gif.h" /*XXX*/ 120 121#if NBPFILTER > 0 122#include <net/bpf.h> 123#endif 124 125#if NGIF > 0 126#include <net/if_gif.h> 127#endif 128 129#if NSTF > 0 130#if NSTF != 1 131# error only single stf interface allowed 132#endif 133 134#define IN6_IS_ADDR_6TO4(x) (ntohs((x)->s6_addr16[0]) == 0x2002) 135#define GET_V4(x) ((struct in_addr *)(&(x)->s6_addr16[1])) 136 137struct stf_softc { 138 struct ifnet sc_if; /* common area */ 139 union { 140 struct route __sc_ro4; 141 struct route_in6 __sc_ro6; /* just for safety */ 142 } __sc_ro46; 143#define sc_ro __sc_ro46.__sc_ro4 144 const struct encaptab *encap_cookie; 145}; 146 147static struct stf_softc *stf; 148static int nstf; 149 150#if NGIF > 0 151extern int ip_gif_ttl; /*XXX*/ 152#else 153static int ip_gif_ttl = 40; /*XXX*/ 154#endif 155 156extern struct protosw in_stf_protosw; 157 158void stfattach __P((void *)); 159static int stf_encapcheck __P((const struct mbuf *, int, int, void *)); 160static struct in6_ifaddr *stf_getsrcifa6 __P((struct ifnet *)); 161static int stf_output __P((struct ifnet *, struct mbuf *, struct sockaddr *, 162 struct rtentry *)); 163static int stf_checkaddr4 __P((struct stf_softc *, struct in_addr *, 164 struct ifnet *)); 165static int stf_checkaddr6 __P((struct stf_softc *, struct in6_addr *, 166 struct ifnet *)); 167static void stf_rtrequest __P((int, struct rtentry *, struct sockaddr *)); 168static int stf_ioctl __P((struct ifnet *, u_long, caddr_t)); 169 170void 171stfattach(dummy) 172 void *dummy; 173{ 174 struct stf_softc *sc; 175 int i; 176 const struct encaptab *p; 177 178 nstf = NSTF; 179 stf = malloc(nstf * sizeof(struct stf_softc), M_DEVBUF, M_WAITOK); 180 bzero(stf, nstf * sizeof(struct stf_softc)); 181 sc = stf; 182 183 /* XXX just in case... */ 184 for (i = 0; i < nstf; i++) { 185 sc = &stf[i]; 186 bzero(sc, sizeof(*sc)); 187 sc->sc_if.if_name = "stf"; 188 sc->sc_if.if_unit = i; 189 190 p = encap_attach_func(AF_INET, IPPROTO_IPV6, stf_encapcheck, 191 &in_stf_protosw, sc); 192 if (p == NULL) { 193 printf("%s: attach failed\n", if_name(&sc->sc_if)); 194 continue; 195 } 196 sc->encap_cookie = p; 197 198 sc->sc_if.if_mtu = IPV6_MMTU; 199 sc->sc_if.if_flags = 0; 200 sc->sc_if.if_ioctl = stf_ioctl; 201 sc->sc_if.if_output = stf_output; 202 sc->sc_if.if_type = IFT_STF; 203#if 0 204 /* turn off ingress filter */ 205 sc->sc_if.if_flags |= IFF_LINK2; 206#endif 207 sc->sc_if.if_snd.ifq_maxlen = IFQ_MAXLEN; 208 if_attach(&sc->sc_if); 209#if NBPFILTER > 0 210#ifdef HAVE_OLD_BPF 211 bpfattach(&sc->sc_if, DLT_NULL, sizeof(u_int)); 212#else 213 bpfattach(&sc->sc_if.if_bpf, &sc->sc_if, DLT_NULL, sizeof(u_int)); 214#endif 215#endif 216 } 217} 218 219PSEUDO_SET(stfattach, if_stf); 220 221static int 222stf_encapcheck(m, off, proto, arg) 223 const struct mbuf *m; 224 int off; 225 int proto; 226 void *arg; 227{ 228 struct ip ip; 229 struct in6_ifaddr *ia6; 230 struct stf_softc *sc; 231 struct in_addr a, b; 232 233 sc = (struct stf_softc *)arg; 234 if (sc == NULL) 235 return 0; 236 237 if ((sc->sc_if.if_flags & IFF_UP) == 0) 238 return 0; 239 240 /* IFF_LINK0 means "no decapsulation" */ 241 if ((sc->sc_if.if_flags & IFF_LINK0) != 0) 242 return 0; 243 244 if (proto != IPPROTO_IPV6) 245 return 0; 246 247 /* LINTED const cast */ 248 m_copydata((struct mbuf *)m, 0, sizeof(ip), (caddr_t)&ip); 249 250 if (ip.ip_v != 4) 251 return 0; 252 253 ia6 = stf_getsrcifa6(&sc->sc_if); 254 if (ia6 == NULL) 255 return 0; 256 257 /* 258 * check if IPv4 dst matches the IPv4 address derived from the 259 * local 6to4 address. 260 * success on: dst = 10.1.1.1, ia6->ia_addr = 2002:0a01:0101:... 261 */ 262 if (bcmp(GET_V4(&ia6->ia_addr.sin6_addr), &ip.ip_dst, 263 sizeof(ip.ip_dst)) != 0) 264 return 0; 265 266 /* 267 * check if IPv4 src matches the IPv4 address derived from the 268 * local 6to4 address masked by prefixmask. 269 * success on: src = 10.1.1.1, ia6->ia_addr = 2002:0a00:.../24 270 * fail on: src = 10.1.1.1, ia6->ia_addr = 2002:0b00:.../24 271 */ 272 bzero(&a, sizeof(a)); 273 a.s_addr = GET_V4(&ia6->ia_addr.sin6_addr)->s_addr; 274 a.s_addr &= GET_V4(&ia6->ia_prefixmask.sin6_addr)->s_addr; 275 b = ip.ip_src; 276 b.s_addr &= GET_V4(&ia6->ia_prefixmask.sin6_addr)->s_addr; 277 if (a.s_addr != b.s_addr) 278 return 0; 279 280 /* stf interface makes single side match only */ 281 return 32; 282} 283 284static struct in6_ifaddr * 285stf_getsrcifa6(ifp) 286 struct ifnet *ifp; 287{ 288 struct ifaddr *ia; 289 struct in_ifaddr *ia4; 290 struct sockaddr_in6 *sin6; 291 struct in_addr in; 292 293 for (ia = TAILQ_FIRST(&ifp->if_addrlist); 294 ia; 295 ia = TAILQ_NEXT(ia, ifa_list)) 296 { 297 if (ia->ifa_addr == NULL) 298 continue; 299 if (ia->ifa_addr->sa_family != AF_INET6) 300 continue; 301 sin6 = (struct sockaddr_in6 *)ia->ifa_addr; 302 if (!IN6_IS_ADDR_6TO4(&sin6->sin6_addr)) 303 continue; 304 305 bcopy(GET_V4(&sin6->sin6_addr), &in, sizeof(in)); 306 for (ia4 = TAILQ_FIRST(&in_ifaddrhead); 307 ia4; 308 ia4 = TAILQ_NEXT(ia4, ia_link)) 309 { 310 if (ia4->ia_addr.sin_addr.s_addr == in.s_addr) 311 break; 312 } 313 if (ia4 == NULL) 314 continue; 315 316 return (struct in6_ifaddr *)ia; 317 } 318 319 return NULL; 320} 321 322static int 323stf_output(ifp, m, dst, rt) 324 struct ifnet *ifp; 325 struct mbuf *m; 326 struct sockaddr *dst; 327 struct rtentry *rt; 328{ 329 struct stf_softc *sc; 330 struct sockaddr_in6 *dst6; 331 struct in_addr *in4; 332 struct sockaddr_in *dst4; 333 u_int8_t tos; 334 struct ip *ip; 335 struct ip6_hdr *ip6; 336 struct in6_ifaddr *ia6; 337 338 sc = (struct stf_softc*)ifp; 339 dst6 = (struct sockaddr_in6 *)dst; 340 341 /* just in case */ 342 if ((ifp->if_flags & IFF_UP) == 0) { 343 m_freem(m); 344 return ENETDOWN; 345 } 346 347 /* 348 * If we don't have an ip4 address that match my inner ip6 address, 349 * we shouldn't generate output. Without this check, we'll end up 350 * using wrong IPv4 source. 351 */ 352 ia6 = stf_getsrcifa6(ifp); 353 if (ia6 == NULL) { 354 m_freem(m); 355 return ENETDOWN; 356 } 357 358 if (m->m_len < sizeof(*ip6)) { 359 m = m_pullup(m, sizeof(*ip6)); 360 if (!m) 361 return ENOBUFS; 362 } 363 ip6 = mtod(m, struct ip6_hdr *); 364 tos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; 365 366 /* 367 * Pickup the right outer dst addr from the list of candidates. 368 * ip6_dst has priority as it may be able to give us shorter IPv4 hops. 369 */ 370 if (IN6_IS_ADDR_6TO4(&ip6->ip6_dst)) 371 in4 = GET_V4(&ip6->ip6_dst); 372 else if (IN6_IS_ADDR_6TO4(&dst6->sin6_addr)) 373 in4 = GET_V4(&dst6->sin6_addr); 374 else { 375 m_freem(m); 376 return ENETUNREACH; 377 } 378 379#if NBPFILTER > 0 380 if (ifp->if_bpf) { 381 /* 382 * We need to prepend the address family as 383 * a four byte field. Cons up a dummy header 384 * to pacify bpf. This is safe because bpf 385 * will only read from the mbuf (i.e., it won't 386 * try to free it or keep a pointer a to it). 387 */ 388 struct mbuf m0; 389 u_int32_t af = AF_INET6; 390 391 m0.m_next = m; 392 m0.m_len = 4; 393 m0.m_data = (char *)⁡ 394 395#ifdef HAVE_OLD_BPF 396 bpf_mtap(ifp, &m0); 397#else 398 bpf_mtap(ifp->if_bpf, &m0); 399#endif 400 } 401#endif /*NBPFILTER > 0*/ 402 403 M_PREPEND(m, sizeof(struct ip), M_DONTWAIT); 404 if (m && m->m_len < sizeof(struct ip)) 405 m = m_pullup(m, sizeof(struct ip)); 406 if (m == NULL) 407 return ENOBUFS; 408 ip = mtod(m, struct ip *); 409 410 bzero(ip, sizeof(*ip)); 411 412 bcopy(GET_V4(&((struct sockaddr_in6 *)&ia6->ia_addr)->sin6_addr), 413 &ip->ip_src, sizeof(ip->ip_src)); 414 bcopy(in4, &ip->ip_dst, sizeof(ip->ip_dst)); 415 ip->ip_p = IPPROTO_IPV6; 416 ip->ip_ttl = ip_gif_ttl; /*XXX*/ 417 ip->ip_len = m->m_pkthdr.len; /*host order*/ 418 if (ifp->if_flags & IFF_LINK1) 419 ip_ecn_ingress(ECN_ALLOWED, &ip->ip_tos, &tos); 420 else 421 ip_ecn_ingress(ECN_NOCARE, &ip->ip_tos, &tos); 422 423 dst4 = (struct sockaddr_in *)&sc->sc_ro.ro_dst; 424 if (dst4->sin_family != AF_INET || 425 bcmp(&dst4->sin_addr, &ip->ip_dst, sizeof(ip->ip_dst)) != 0) { 426 /* cache route doesn't match */ 427 dst4->sin_family = AF_INET; 428 dst4->sin_len = sizeof(struct sockaddr_in); 429 bcopy(&ip->ip_dst, &dst4->sin_addr, sizeof(dst4->sin_addr)); 430 if (sc->sc_ro.ro_rt) { 431 RTFREE(sc->sc_ro.ro_rt); 432 sc->sc_ro.ro_rt = NULL; 433 } 434 } 435 436 if (sc->sc_ro.ro_rt == NULL) { 437 rtalloc(&sc->sc_ro); 438 if (sc->sc_ro.ro_rt == NULL) { 439 m_freem(m); 440 return ENETUNREACH; 441 } 442 } 443 444 return ip_output(m, NULL, &sc->sc_ro, 0, NULL); 445} 446 447static int 448stf_checkaddr4(sc, in, inifp) 449 struct stf_softc *sc; 450 struct in_addr *in; 451 struct ifnet *inifp; /* incoming interface */ 452{ 453 struct in_ifaddr *ia4; 454 455 /* 456 * reject packets with the following address: 457 * 224.0.0.0/4 0.0.0.0/8 127.0.0.0/8 255.0.0.0/8 458 */ 459 if (IN_MULTICAST(ntohl(in->s_addr))) 460 return -1; 461 switch ((ntohl(in->s_addr) & 0xff000000) >> 24) { 462 case 0: case 127: case 255: 463 return -1; 464 } 465 466 /* 467 * reject packets with broadcast 468 */ 469 for (ia4 = TAILQ_FIRST(&in_ifaddrhead); 470 ia4; 471 ia4 = TAILQ_NEXT(ia4, ia_link)) 472 { 473 if ((ia4->ia_ifa.ifa_ifp->if_flags & IFF_BROADCAST) == 0) 474 continue; 475 if (in->s_addr == ia4->ia_broadaddr.sin_addr.s_addr) 476 return -1; 477 } 478 479 /* 480 * perform ingress filter 481 */ 482 if (sc && (sc->sc_if.if_flags & IFF_LINK2) == 0 && inifp) { 483 struct sockaddr_in sin; 484 struct rtentry *rt; 485 486 bzero(&sin, sizeof(sin)); 487 sin.sin_family = AF_INET; 488 sin.sin_len = sizeof(struct sockaddr_in); 489 sin.sin_addr = *in; 490 rt = rtalloc1((struct sockaddr *)&sin, 0, 0UL); 491 if (!rt || rt->rt_ifp != inifp) { 492#if 0 493 log(LOG_WARNING, "%s: packet from 0x%x dropped " 494 "due to ingress filter\n", if_name(&sc->sc_if), 495 (u_int32_t)ntohl(sin.sin_addr.s_addr)); 496#endif 497 if (rt) 498 rtfree(rt); 499 return -1; 500 } 501 rtfree(rt); 502 } 503 504 return 0; 505} 506 507static int 508stf_checkaddr6(sc, in6, inifp) 509 struct stf_softc *sc; 510 struct in6_addr *in6; 511 struct ifnet *inifp; /* incoming interface */ 512{ 513 /* 514 * check 6to4 addresses 515 */ 516 if (IN6_IS_ADDR_6TO4(in6)) 517 return stf_checkaddr4(sc, GET_V4(in6), inifp); 518 519 /* 520 * reject anything that look suspicious. the test is implemented 521 * in ip6_input too, but we check here as well to 522 * (1) reject bad packets earlier, and 523 * (2) to be safe against future ip6_input change. 524 */ 525 if (IN6_IS_ADDR_V4COMPAT(in6) || IN6_IS_ADDR_V4MAPPED(in6)) 526 return -1; 527 528 return 0; 529} 530 531void 532#if __STDC__ 533in_stf_input(struct mbuf *m, ...) 534#else 535in_stf_input(m, va_alist) 536 struct mbuf *m; 537#endif 538{ 539 int off, proto; 540 struct stf_softc *sc; 541 struct ip *ip; 542 struct ip6_hdr *ip6; 543 u_int8_t otos, itos; 544 int len, isr; 545 struct ifqueue *ifq = NULL; 546 struct ifnet *ifp; 547 va_list ap; 548 549 va_start(ap, m); 550 off = va_arg(ap, int); 551 proto = va_arg(ap, int); 552 va_end(ap); 553 554 if (proto != IPPROTO_IPV6) { 555 m_freem(m); 556 return; 557 } 558 559 ip = mtod(m, struct ip *); 560 561 sc = (struct stf_softc *)encap_getarg(m); 562 563 if (sc == NULL || (sc->sc_if.if_flags & IFF_UP) == 0) { 564 m_freem(m); 565 return; 566 } 567 568 ifp = &sc->sc_if; 569 570 /* 571 * perform sanity check against outer src/dst. 572 * for source, perform ingress filter as well. 573 */ 574 if (stf_checkaddr4(sc, &ip->ip_dst, NULL) < 0 || 575 stf_checkaddr4(sc, &ip->ip_src, m->m_pkthdr.rcvif) < 0) { 576 m_freem(m); 577 return; 578 } 579 580 otos = ip->ip_tos; 581 m_adj(m, off); 582 583 if (m->m_len < sizeof(*ip6)) { 584 m = m_pullup(m, sizeof(*ip6)); 585 if (!m) 586 return; 587 } 588 ip6 = mtod(m, struct ip6_hdr *); 589 590 /* 591 * perform sanity check against inner src/dst. 592 * for source, perform ingress filter as well. 593 */ 594 if (stf_checkaddr6(sc, &ip6->ip6_dst, NULL) < 0 || 595 stf_checkaddr6(sc, &ip6->ip6_src, m->m_pkthdr.rcvif) < 0) { 596 m_freem(m); 597 return; 598 } 599 600 itos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; 601 if ((ifp->if_flags & IFF_LINK1) != 0) 602 ip_ecn_egress(ECN_ALLOWED, &otos, &itos); 603 else 604 ip_ecn_egress(ECN_NOCARE, &otos, &itos); 605 ip6->ip6_flow &= ~htonl(0xff << 20); 606 ip6->ip6_flow |= htonl((u_int32_t)itos << 20); 607 608 m->m_pkthdr.rcvif = ifp; 609 610#if NBPFILTER > 0 611 if (ifp->if_bpf) { 612 /* 613 * We need to prepend the address family as 614 * a four byte field. Cons up a dummy header 615 * to pacify bpf. This is safe because bpf 616 * will only read from the mbuf (i.e., it won't 617 * try to free it or keep a pointer a to it). 618 */ 619 struct mbuf m0; 620 u_int32_t af = AF_INET6; 621 622 m0.m_next = m; 623 m0.m_len = 4; 624 m0.m_data = (char *)⁡ 625 626#ifdef HAVE_OLD_BPF 627 bpf_mtap(ifp, &m0); 628#else 629 bpf_mtap(ifp->if_bpf, &m0); 630#endif 631 } 632#endif /*NBPFILTER > 0*/ 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 */ 652static void 653stf_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 663static int 664stf_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} 706 707#endif /* NSTF > 0 */ 708