1 /* $FreeBSD$ */ 2 /* $KAME: if_stf.c,v 1.73 2001/12/03 11:08:30 keiichi 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 #include "opt_mac.h" 80 81 #include <sys/param.h> 82 #include <sys/systm.h> 83 #include <sys/socket.h> 84 #include <sys/sockio.h> 85 #include <sys/mac.h> 86 #include <sys/mbuf.h> 87 #include <sys/errno.h> 88 #include <sys/kernel.h> 89 #include <sys/module.h> 90 #include <sys/protosw.h> 91 #include <sys/queue.h> 92 #include <machine/cpu.h> 93 94 #include <sys/malloc.h> 95 96 #include <net/if.h> 97 #include <net/if_clone.h> 98 #include <net/route.h> 99 #include <net/netisr.h> 100 #include <net/if_types.h> 101 #include <net/if_stf.h> 102 103 #include <netinet/in.h> 104 #include <netinet/in_systm.h> 105 #include <netinet/ip.h> 106 #include <netinet/ip_var.h> 107 #include <netinet/in_var.h> 108 109 #include <netinet/ip6.h> 110 #include <netinet6/ip6_var.h> 111 #include <netinet6/in6_var.h> 112 #include <netinet/ip_ecn.h> 113 114 #include <netinet/ip_encap.h> 115 116 #include <machine/stdarg.h> 117 118 #include <net/bpf.h> 119 120 #define STFNAME "stf" 121 #define STFUNIT 0 122 123 #define IN6_IS_ADDR_6TO4(x) (ntohs((x)->s6_addr16[0]) == 0x2002) 124 125 /* 126 * XXX: Return a pointer with 16-bit aligned. Don't cast it to 127 * struct in_addr *; use bcopy() instead. 128 */ 129 #define GET_V4(x) ((caddr_t)(&(x)->s6_addr16[1])) 130 131 struct stf_softc { 132 struct ifnet *sc_ifp; 133 union { 134 struct route __sc_ro4; 135 struct route_in6 __sc_ro6; /* just for safety */ 136 } __sc_ro46; 137 #define sc_ro __sc_ro46.__sc_ro4 138 const struct encaptab *encap_cookie; 139 }; 140 #define STF2IFP(sc) ((sc)->sc_ifp) 141 142 /* 143 * XXXRW: Note that mutable fields in the softc are not currently locked: 144 * in particular, sc_ro needs to be protected from concurrent entrance 145 * of stf_output(). 146 */ 147 static MALLOC_DEFINE(M_STF, STFNAME, "6to4 Tunnel Interface"); 148 static const int ip_stf_ttl = 40; 149 150 extern struct domain inetdomain; 151 struct protosw in_stf_protosw = { 152 .pr_type = SOCK_RAW, 153 .pr_domain = &inetdomain, 154 .pr_protocol = IPPROTO_IPV6, 155 .pr_flags = PR_ATOMIC|PR_ADDR, 156 .pr_input = in_stf_input, 157 .pr_output = (pr_output_t *)rip_output, 158 .pr_ctloutput = rip_ctloutput, 159 .pr_usrreqs = &rip_usrreqs 160 }; 161 162 static char *stfnames[] = {"stf0", "stf", "6to4", NULL}; 163 164 static int stfmodevent(module_t, int, void *); 165 static int stf_encapcheck(const struct mbuf *, int, int, void *); 166 static struct in6_ifaddr *stf_getsrcifa6(struct ifnet *); 167 static int stf_output(struct ifnet *, struct mbuf *, struct sockaddr *, 168 struct rtentry *); 169 static int isrfc1918addr(struct in_addr *); 170 static int stf_checkaddr4(struct stf_softc *, struct in_addr *, 171 struct ifnet *); 172 static int stf_checkaddr6(struct stf_softc *, struct in6_addr *, 173 struct ifnet *); 174 static void stf_rtrequest(int, struct rtentry *, struct rt_addrinfo *); 175 static int stf_ioctl(struct ifnet *, u_long, caddr_t); 176 177 static int stf_clone_match(struct if_clone *, const char *); 178 static int stf_clone_create(struct if_clone *, char *, size_t, caddr_t); 179 static int stf_clone_destroy(struct if_clone *, struct ifnet *); 180 struct if_clone stf_cloner = IFC_CLONE_INITIALIZER(STFNAME, NULL, 0, 181 NULL, stf_clone_match, stf_clone_create, stf_clone_destroy); 182 183 static int 184 stf_clone_match(struct if_clone *ifc, const char *name) 185 { 186 int i; 187 188 for(i = 0; stfnames[i] != NULL; i++) { 189 if (strcmp(stfnames[i], name) == 0) 190 return (1); 191 } 192 193 return (0); 194 } 195 196 static int 197 stf_clone_create(struct if_clone *ifc, char *name, size_t len, caddr_t params) 198 { 199 int err, unit; 200 struct stf_softc *sc; 201 struct ifnet *ifp; 202 203 /* 204 * We can only have one unit, but since unit allocation is 205 * already locked, we use it to keep from allocating extra 206 * interfaces. 207 */ 208 unit = STFUNIT; 209 err = ifc_alloc_unit(ifc, &unit); 210 if (err != 0) 211 return (err); 212 213 sc = malloc(sizeof(struct stf_softc), M_STF, M_WAITOK | M_ZERO); 214 ifp = STF2IFP(sc) = if_alloc(IFT_STF); 215 if (ifp == NULL) { 216 free(sc, M_STF); 217 ifc_free_unit(ifc, unit); 218 return (ENOSPC); 219 } 220 ifp->if_softc = sc; 221 222 /* 223 * Set the name manually rather then using if_initname because 224 * we don't conform to the default naming convention for interfaces. 225 */ 226 strlcpy(ifp->if_xname, name, IFNAMSIZ); 227 ifp->if_dname = ifc->ifc_name; 228 ifp->if_dunit = IF_DUNIT_NONE; 229 230 sc->encap_cookie = encap_attach_func(AF_INET, IPPROTO_IPV6, 231 stf_encapcheck, &in_stf_protosw, sc); 232 if (sc->encap_cookie == NULL) { 233 if_printf(ifp, "attach failed\n"); 234 free(sc, M_STF); 235 ifc_free_unit(ifc, unit); 236 return (ENOMEM); 237 } 238 239 ifp->if_mtu = IPV6_MMTU; 240 ifp->if_ioctl = stf_ioctl; 241 ifp->if_output = stf_output; 242 ifp->if_snd.ifq_maxlen = IFQ_MAXLEN; 243 if_attach(ifp); 244 bpfattach(ifp, DLT_NULL, sizeof(u_int32_t)); 245 return (0); 246 } 247 248 static int 249 stf_clone_destroy(struct if_clone *ifc, struct ifnet *ifp) 250 { 251 struct stf_softc *sc = ifp->if_softc; 252 int err; 253 254 err = encap_detach(sc->encap_cookie); 255 KASSERT(err == 0, ("Unexpected error detaching encap_cookie")); 256 bpfdetach(ifp); 257 if_detach(ifp); 258 if_free(ifp); 259 260 free(sc, M_STF); 261 ifc_free_unit(ifc, STFUNIT); 262 263 return (0); 264 } 265 266 static int 267 stfmodevent(mod, type, data) 268 module_t mod; 269 int type; 270 void *data; 271 { 272 273 switch (type) { 274 case MOD_LOAD: 275 if_clone_attach(&stf_cloner); 276 break; 277 case MOD_UNLOAD: 278 if_clone_detach(&stf_cloner); 279 break; 280 default: 281 return (EOPNOTSUPP); 282 } 283 284 return (0); 285 } 286 287 static moduledata_t stf_mod = { 288 "if_stf", 289 stfmodevent, 290 0 291 }; 292 293 DECLARE_MODULE(if_stf, stf_mod, SI_SUB_PSEUDO, SI_ORDER_ANY); 294 295 static int 296 stf_encapcheck(m, off, proto, arg) 297 const struct mbuf *m; 298 int off; 299 int proto; 300 void *arg; 301 { 302 struct ip ip; 303 struct in6_ifaddr *ia6; 304 struct stf_softc *sc; 305 struct in_addr a, b, mask; 306 307 sc = (struct stf_softc *)arg; 308 if (sc == NULL) 309 return 0; 310 311 if ((STF2IFP(sc)->if_flags & IFF_UP) == 0) 312 return 0; 313 314 /* IFF_LINK0 means "no decapsulation" */ 315 if ((STF2IFP(sc)->if_flags & IFF_LINK0) != 0) 316 return 0; 317 318 if (proto != IPPROTO_IPV6) 319 return 0; 320 321 /* LINTED const cast */ 322 m_copydata((struct mbuf *)(uintptr_t)m, 0, sizeof(ip), (caddr_t)&ip); 323 324 if (ip.ip_v != 4) 325 return 0; 326 327 ia6 = stf_getsrcifa6(STF2IFP(sc)); 328 if (ia6 == NULL) 329 return 0; 330 331 /* 332 * check if IPv4 dst matches the IPv4 address derived from the 333 * local 6to4 address. 334 * success on: dst = 10.1.1.1, ia6->ia_addr = 2002:0a01:0101:... 335 */ 336 if (bcmp(GET_V4(&ia6->ia_addr.sin6_addr), &ip.ip_dst, 337 sizeof(ip.ip_dst)) != 0) 338 return 0; 339 340 /* 341 * check if IPv4 src matches the IPv4 address derived from the 342 * local 6to4 address masked by prefixmask. 343 * success on: src = 10.1.1.1, ia6->ia_addr = 2002:0a00:.../24 344 * fail on: src = 10.1.1.1, ia6->ia_addr = 2002:0b00:.../24 345 */ 346 bzero(&a, sizeof(a)); 347 bcopy(GET_V4(&ia6->ia_addr.sin6_addr), &a, sizeof(a)); 348 bcopy(GET_V4(&ia6->ia_prefixmask.sin6_addr), &mask, sizeof(mask)); 349 a.s_addr &= mask.s_addr; 350 b = ip.ip_src; 351 b.s_addr &= mask.s_addr; 352 if (a.s_addr != b.s_addr) 353 return 0; 354 355 /* stf interface makes single side match only */ 356 return 32; 357 } 358 359 static struct in6_ifaddr * 360 stf_getsrcifa6(ifp) 361 struct ifnet *ifp; 362 { 363 struct ifaddr *ia; 364 struct in_ifaddr *ia4; 365 struct sockaddr_in6 *sin6; 366 struct in_addr in; 367 368 TAILQ_FOREACH(ia, &ifp->if_addrlist, ifa_list) { 369 if (ia->ifa_addr->sa_family != AF_INET6) 370 continue; 371 sin6 = (struct sockaddr_in6 *)ia->ifa_addr; 372 if (!IN6_IS_ADDR_6TO4(&sin6->sin6_addr)) 373 continue; 374 375 bcopy(GET_V4(&sin6->sin6_addr), &in, sizeof(in)); 376 LIST_FOREACH(ia4, INADDR_HASH(in.s_addr), ia_hash) 377 if (ia4->ia_addr.sin_addr.s_addr == in.s_addr) 378 break; 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 caddr_t ptr; 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 u_int32_t af; 405 #ifdef MAC 406 int error; 407 408 error = mac_check_ifnet_transmit(ifp, m); 409 if (error) { 410 m_freem(m); 411 return (error); 412 } 413 #endif 414 415 sc = ifp->if_softc; 416 dst6 = (struct sockaddr_in6 *)dst; 417 418 /* just in case */ 419 if ((ifp->if_flags & IFF_UP) == 0) { 420 m_freem(m); 421 ifp->if_oerrors++; 422 return ENETDOWN; 423 } 424 425 /* 426 * If we don't have an ip4 address that match my inner ip6 address, 427 * we shouldn't generate output. Without this check, we'll end up 428 * using wrong IPv4 source. 429 */ 430 ia6 = stf_getsrcifa6(ifp); 431 if (ia6 == NULL) { 432 m_freem(m); 433 ifp->if_oerrors++; 434 return ENETDOWN; 435 } 436 437 if (m->m_len < sizeof(*ip6)) { 438 m = m_pullup(m, sizeof(*ip6)); 439 if (!m) { 440 ifp->if_oerrors++; 441 return ENOBUFS; 442 } 443 } 444 ip6 = mtod(m, struct ip6_hdr *); 445 tos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; 446 447 /* 448 * BPF writes need to be handled specially. 449 * This is a null operation, nothing here checks dst->sa_family. 450 */ 451 if (dst->sa_family == AF_UNSPEC) { 452 bcopy(dst->sa_data, &af, sizeof(af)); 453 dst->sa_family = af; 454 } 455 456 /* 457 * Pickup the right outer dst addr from the list of candidates. 458 * ip6_dst has priority as it may be able to give us shorter IPv4 hops. 459 */ 460 ptr = NULL; 461 if (IN6_IS_ADDR_6TO4(&ip6->ip6_dst)) 462 ptr = GET_V4(&ip6->ip6_dst); 463 else if (IN6_IS_ADDR_6TO4(&dst6->sin6_addr)) 464 ptr = GET_V4(&dst6->sin6_addr); 465 else { 466 m_freem(m); 467 ifp->if_oerrors++; 468 return ENETUNREACH; 469 } 470 bcopy(ptr, &in4, sizeof(in4)); 471 472 if (bpf_peers_present(ifp->if_bpf)) { 473 /* 474 * We need to prepend the address family as 475 * a four byte field. Cons up a dummy header 476 * to pacify bpf. This is safe because bpf 477 * will only read from the mbuf (i.e., it won't 478 * try to free it or keep a pointer a to it). 479 */ 480 af = AF_INET6; 481 bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m); 482 } 483 484 M_PREPEND(m, sizeof(struct ip), M_DONTWAIT); 485 if (m && m->m_len < sizeof(struct ip)) 486 m = m_pullup(m, sizeof(struct ip)); 487 if (m == NULL) { 488 ifp->if_oerrors++; 489 return ENOBUFS; 490 } 491 ip = mtod(m, struct ip *); 492 493 bzero(ip, sizeof(*ip)); 494 495 bcopy(GET_V4(&((struct sockaddr_in6 *)&ia6->ia_addr)->sin6_addr), 496 &ip->ip_src, sizeof(ip->ip_src)); 497 bcopy(&in4, &ip->ip_dst, sizeof(ip->ip_dst)); 498 ip->ip_p = IPPROTO_IPV6; 499 ip->ip_ttl = ip_stf_ttl; 500 ip->ip_len = m->m_pkthdr.len; /*host order*/ 501 if (ifp->if_flags & IFF_LINK1) 502 ip_ecn_ingress(ECN_ALLOWED, &ip->ip_tos, &tos); 503 else 504 ip_ecn_ingress(ECN_NOCARE, &ip->ip_tos, &tos); 505 506 /* 507 * XXXRW: Locking of sc_ro required. 508 */ 509 dst4 = (struct sockaddr_in *)&sc->sc_ro.ro_dst; 510 if (dst4->sin_family != AF_INET || 511 bcmp(&dst4->sin_addr, &ip->ip_dst, sizeof(ip->ip_dst)) != 0) { 512 /* cache route doesn't match */ 513 dst4->sin_family = AF_INET; 514 dst4->sin_len = sizeof(struct sockaddr_in); 515 bcopy(&ip->ip_dst, &dst4->sin_addr, sizeof(dst4->sin_addr)); 516 if (sc->sc_ro.ro_rt) { 517 RTFREE(sc->sc_ro.ro_rt); 518 sc->sc_ro.ro_rt = NULL; 519 } 520 } 521 522 if (sc->sc_ro.ro_rt == NULL) { 523 rtalloc(&sc->sc_ro); 524 if (sc->sc_ro.ro_rt == NULL) { 525 m_freem(m); 526 ifp->if_oerrors++; 527 return ENETUNREACH; 528 } 529 } 530 531 ifp->if_opackets++; 532 return ip_output(m, NULL, &sc->sc_ro, 0, NULL, NULL); 533 } 534 535 static int 536 isrfc1918addr(in) 537 struct in_addr *in; 538 { 539 /* 540 * returns 1 if private address range: 541 * 10.0.0.0/8 172.16.0.0/12 192.168.0.0/16 542 */ 543 if ((ntohl(in->s_addr) & 0xff000000) >> 24 == 10 || 544 (ntohl(in->s_addr) & 0xfff00000) >> 16 == 172 * 256 + 16 || 545 (ntohl(in->s_addr) & 0xffff0000) >> 16 == 192 * 256 + 168) 546 return 1; 547 548 return 0; 549 } 550 551 static int 552 stf_checkaddr4(sc, in, inifp) 553 struct stf_softc *sc; 554 struct in_addr *in; 555 struct ifnet *inifp; /* incoming interface */ 556 { 557 struct in_ifaddr *ia4; 558 559 /* 560 * reject packets with the following address: 561 * 224.0.0.0/4 0.0.0.0/8 127.0.0.0/8 255.0.0.0/8 562 */ 563 if (IN_MULTICAST(ntohl(in->s_addr))) 564 return -1; 565 switch ((ntohl(in->s_addr) & 0xff000000) >> 24) { 566 case 0: case 127: case 255: 567 return -1; 568 } 569 570 /* 571 * reject packets with private address range. 572 * (requirement from RFC3056 section 2 1st paragraph) 573 */ 574 if (isrfc1918addr(in)) 575 return -1; 576 577 /* 578 * reject packets with broadcast 579 */ 580 for (ia4 = TAILQ_FIRST(&in_ifaddrhead); 581 ia4; 582 ia4 = TAILQ_NEXT(ia4, ia_link)) 583 { 584 if ((ia4->ia_ifa.ifa_ifp->if_flags & IFF_BROADCAST) == 0) 585 continue; 586 if (in->s_addr == ia4->ia_broadaddr.sin_addr.s_addr) 587 return -1; 588 } 589 590 /* 591 * perform ingress filter 592 */ 593 if (sc && (STF2IFP(sc)->if_flags & IFF_LINK2) == 0 && inifp) { 594 struct sockaddr_in sin; 595 struct rtentry *rt; 596 597 bzero(&sin, sizeof(sin)); 598 sin.sin_family = AF_INET; 599 sin.sin_len = sizeof(struct sockaddr_in); 600 sin.sin_addr = *in; 601 rt = rtalloc1((struct sockaddr *)&sin, 0, 0UL); 602 if (!rt || rt->rt_ifp != inifp) { 603 #if 0 604 log(LOG_WARNING, "%s: packet from 0x%x dropped " 605 "due to ingress filter\n", if_name(STF2IFP(sc)), 606 (u_int32_t)ntohl(sin.sin_addr.s_addr)); 607 #endif 608 if (rt) 609 rtfree(rt); 610 return -1; 611 } 612 rtfree(rt); 613 } 614 615 return 0; 616 } 617 618 static int 619 stf_checkaddr6(sc, in6, inifp) 620 struct stf_softc *sc; 621 struct in6_addr *in6; 622 struct ifnet *inifp; /* incoming interface */ 623 { 624 /* 625 * check 6to4 addresses 626 */ 627 if (IN6_IS_ADDR_6TO4(in6)) { 628 struct in_addr in4; 629 bcopy(GET_V4(in6), &in4, sizeof(in4)); 630 return stf_checkaddr4(sc, &in4, inifp); 631 } 632 633 /* 634 * reject anything that look suspicious. the test is implemented 635 * in ip6_input too, but we check here as well to 636 * (1) reject bad packets earlier, and 637 * (2) to be safe against future ip6_input change. 638 */ 639 if (IN6_IS_ADDR_V4COMPAT(in6) || IN6_IS_ADDR_V4MAPPED(in6)) 640 return -1; 641 642 return 0; 643 } 644 645 void 646 in_stf_input(m, off) 647 struct mbuf *m; 648 int off; 649 { 650 int proto; 651 struct stf_softc *sc; 652 struct ip *ip; 653 struct ip6_hdr *ip6; 654 u_int8_t otos, itos; 655 struct ifnet *ifp; 656 657 proto = mtod(m, struct ip *)->ip_p; 658 659 if (proto != IPPROTO_IPV6) { 660 m_freem(m); 661 return; 662 } 663 664 ip = mtod(m, struct ip *); 665 666 sc = (struct stf_softc *)encap_getarg(m); 667 668 if (sc == NULL || (STF2IFP(sc)->if_flags & IFF_UP) == 0) { 669 m_freem(m); 670 return; 671 } 672 673 ifp = STF2IFP(sc); 674 675 #ifdef MAC 676 mac_create_mbuf_from_ifnet(ifp, m); 677 #endif 678 679 /* 680 * perform sanity check against outer src/dst. 681 * for source, perform ingress filter as well. 682 */ 683 if (stf_checkaddr4(sc, &ip->ip_dst, NULL) < 0 || 684 stf_checkaddr4(sc, &ip->ip_src, m->m_pkthdr.rcvif) < 0) { 685 m_freem(m); 686 return; 687 } 688 689 otos = ip->ip_tos; 690 m_adj(m, off); 691 692 if (m->m_len < sizeof(*ip6)) { 693 m = m_pullup(m, sizeof(*ip6)); 694 if (!m) 695 return; 696 } 697 ip6 = mtod(m, struct ip6_hdr *); 698 699 /* 700 * perform sanity check against inner src/dst. 701 * for source, perform ingress filter as well. 702 */ 703 if (stf_checkaddr6(sc, &ip6->ip6_dst, NULL) < 0 || 704 stf_checkaddr6(sc, &ip6->ip6_src, m->m_pkthdr.rcvif) < 0) { 705 m_freem(m); 706 return; 707 } 708 709 itos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; 710 if ((ifp->if_flags & IFF_LINK1) != 0) 711 ip_ecn_egress(ECN_ALLOWED, &otos, &itos); 712 else 713 ip_ecn_egress(ECN_NOCARE, &otos, &itos); 714 ip6->ip6_flow &= ~htonl(0xff << 20); 715 ip6->ip6_flow |= htonl((u_int32_t)itos << 20); 716 717 m->m_pkthdr.rcvif = ifp; 718 719 if (bpf_peers_present(ifp->if_bpf)) { 720 /* 721 * We need to prepend the address family as 722 * a four byte field. Cons up a dummy header 723 * to pacify bpf. This is safe because bpf 724 * will only read from the mbuf (i.e., it won't 725 * try to free it or keep a pointer a to it). 726 */ 727 u_int32_t af = AF_INET6; 728 bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m); 729 } 730 731 /* 732 * Put the packet to the network layer input queue according to the 733 * specified address family. 734 * See net/if_gif.c for possible issues with packet processing 735 * reorder due to extra queueing. 736 */ 737 ifp->if_ipackets++; 738 ifp->if_ibytes += m->m_pkthdr.len; 739 netisr_dispatch(NETISR_IPV6, m); 740 } 741 742 /* ARGSUSED */ 743 static void 744 stf_rtrequest(cmd, rt, info) 745 int cmd; 746 struct rtentry *rt; 747 struct rt_addrinfo *info; 748 { 749 RT_LOCK_ASSERT(rt); 750 rt->rt_rmx.rmx_mtu = IPV6_MMTU; 751 } 752 753 static int 754 stf_ioctl(ifp, cmd, data) 755 struct ifnet *ifp; 756 u_long cmd; 757 caddr_t data; 758 { 759 struct ifaddr *ifa; 760 struct ifreq *ifr; 761 struct sockaddr_in6 *sin6; 762 struct in_addr addr; 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 error = EINVAL; 776 break; 777 } 778 bcopy(GET_V4(&sin6->sin6_addr), &addr, sizeof(addr)); 779 if (isrfc1918addr(&addr)) { 780 error = EINVAL; 781 break; 782 } 783 784 ifa->ifa_rtrequest = stf_rtrequest; 785 ifp->if_flags |= IFF_UP; 786 break; 787 788 case SIOCADDMULTI: 789 case SIOCDELMULTI: 790 ifr = (struct ifreq *)data; 791 if (ifr && ifr->ifr_addr.sa_family == AF_INET6) 792 ; 793 else 794 error = EAFNOSUPPORT; 795 break; 796 797 default: 798 error = EINVAL; 799 break; 800 } 801 802 return error; 803 } 804