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 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/kernel.h> 87 #include <sys/module.h> 88 #include <sys/protosw.h> 89 #include <sys/proc.h> 90 #include <sys/queue.h> 91 #include <sys/sysctl.h> 92 #include <machine/cpu.h> 93 94 #include <sys/malloc.h> 95 96 #include <net/if.h> 97 #include <net/if_var.h> 98 #include <net/if_clone.h> 99 #include <net/route.h> 100 #include <net/netisr.h> 101 #include <net/if_types.h> 102 #include <net/if_stf.h> 103 #include <net/vnet.h> 104 105 #include <netinet/in.h> 106 #include <netinet/in_systm.h> 107 #include <netinet/ip.h> 108 #include <netinet/ip_var.h> 109 #include <netinet/in_var.h> 110 111 #include <netinet/ip6.h> 112 #include <netinet6/ip6_var.h> 113 #include <netinet6/in6_var.h> 114 #include <netinet/ip_ecn.h> 115 116 #include <netinet/ip_encap.h> 117 118 #include <machine/stdarg.h> 119 120 #include <net/bpf.h> 121 122 #include <security/mac/mac_framework.h> 123 124 SYSCTL_DECL(_net_link); 125 static SYSCTL_NODE(_net_link, IFT_STF, stf, CTLFLAG_RW, 0, "6to4 Interface"); 126 127 static int stf_permit_rfc1918 = 0; 128 SYSCTL_INT(_net_link_stf, OID_AUTO, permit_rfc1918, CTLFLAG_RWTUN, 129 &stf_permit_rfc1918, 0, "Permit the use of private IPv4 addresses"); 130 131 #define STFUNIT 0 132 133 #define IN6_IS_ADDR_6TO4(x) (ntohs((x)->s6_addr16[0]) == 0x2002) 134 135 /* 136 * XXX: Return a pointer with 16-bit aligned. Don't cast it to 137 * struct in_addr *; use bcopy() instead. 138 */ 139 #define GET_V4(x) (&(x)->s6_addr16[1]) 140 141 struct stf_softc { 142 struct ifnet *sc_ifp; 143 struct mtx sc_ro_mtx; 144 u_int sc_fibnum; 145 const struct encaptab *encap_cookie; 146 }; 147 #define STF2IFP(sc) ((sc)->sc_ifp) 148 149 static const char stfname[] = "stf"; 150 151 /* 152 * Note that mutable fields in the softc are not currently locked. 153 * We do lock sc_ro in stf_output though. 154 */ 155 static MALLOC_DEFINE(M_STF, stfname, "6to4 Tunnel Interface"); 156 static const int ip_stf_ttl = 40; 157 158 extern struct domain inetdomain; 159 struct protosw in_stf_protosw = { 160 .pr_type = SOCK_RAW, 161 .pr_domain = &inetdomain, 162 .pr_protocol = IPPROTO_IPV6, 163 .pr_flags = PR_ATOMIC|PR_ADDR, 164 .pr_input = in_stf_input, 165 .pr_output = rip_output, 166 .pr_ctloutput = rip_ctloutput, 167 .pr_usrreqs = &rip_usrreqs 168 }; 169 170 static char *stfnames[] = {"stf0", "stf", "6to4", NULL}; 171 172 static int stfmodevent(module_t, int, void *); 173 static int stf_encapcheck(const struct mbuf *, int, int, void *); 174 static int stf_getsrcifa6(struct ifnet *, struct in6_addr *, struct in6_addr *); 175 static int stf_output(struct ifnet *, struct mbuf *, const struct sockaddr *, 176 struct route *); 177 static int isrfc1918addr(struct in_addr *); 178 static int stf_checkaddr4(struct stf_softc *, struct in_addr *, 179 struct ifnet *); 180 static int stf_checkaddr6(struct stf_softc *, struct in6_addr *, 181 struct ifnet *); 182 static int stf_ioctl(struct ifnet *, u_long, caddr_t); 183 184 static int stf_clone_match(struct if_clone *, const char *); 185 static int stf_clone_create(struct if_clone *, char *, size_t, caddr_t); 186 static int stf_clone_destroy(struct if_clone *, struct ifnet *); 187 static struct if_clone *stf_cloner; 188 189 static int 190 stf_clone_match(struct if_clone *ifc, const char *name) 191 { 192 int i; 193 194 for(i = 0; stfnames[i] != NULL; i++) { 195 if (strcmp(stfnames[i], name) == 0) 196 return (1); 197 } 198 199 return (0); 200 } 201 202 static int 203 stf_clone_create(struct if_clone *ifc, char *name, size_t len, caddr_t params) 204 { 205 int err, unit; 206 struct stf_softc *sc; 207 struct ifnet *ifp; 208 209 /* 210 * We can only have one unit, but since unit allocation is 211 * already locked, we use it to keep from allocating extra 212 * interfaces. 213 */ 214 unit = STFUNIT; 215 err = ifc_alloc_unit(ifc, &unit); 216 if (err != 0) 217 return (err); 218 219 sc = malloc(sizeof(struct stf_softc), M_STF, M_WAITOK | M_ZERO); 220 ifp = STF2IFP(sc) = if_alloc(IFT_STF); 221 if (ifp == NULL) { 222 free(sc, M_STF); 223 ifc_free_unit(ifc, unit); 224 return (ENOSPC); 225 } 226 ifp->if_softc = sc; 227 sc->sc_fibnum = curthread->td_proc->p_fibnum; 228 229 /* 230 * Set the name manually rather then using if_initname because 231 * we don't conform to the default naming convention for interfaces. 232 */ 233 strlcpy(ifp->if_xname, name, IFNAMSIZ); 234 ifp->if_dname = stfname; 235 ifp->if_dunit = IF_DUNIT_NONE; 236 237 mtx_init(&(sc)->sc_ro_mtx, "stf ro", NULL, MTX_DEF); 238 sc->encap_cookie = encap_attach_func(AF_INET, IPPROTO_IPV6, 239 stf_encapcheck, &in_stf_protosw, sc); 240 if (sc->encap_cookie == NULL) { 241 if_printf(ifp, "attach failed\n"); 242 free(sc, M_STF); 243 ifc_free_unit(ifc, unit); 244 return (ENOMEM); 245 } 246 247 ifp->if_mtu = IPV6_MMTU; 248 ifp->if_ioctl = stf_ioctl; 249 ifp->if_output = stf_output; 250 ifp->if_snd.ifq_maxlen = ifqmaxlen; 251 if_attach(ifp); 252 bpfattach(ifp, DLT_NULL, sizeof(u_int32_t)); 253 return (0); 254 } 255 256 static int 257 stf_clone_destroy(struct if_clone *ifc, struct ifnet *ifp) 258 { 259 struct stf_softc *sc = ifp->if_softc; 260 int err; 261 262 err = encap_detach(sc->encap_cookie); 263 KASSERT(err == 0, ("Unexpected error detaching encap_cookie")); 264 mtx_destroy(&(sc)->sc_ro_mtx); 265 bpfdetach(ifp); 266 if_detach(ifp); 267 if_free(ifp); 268 269 free(sc, M_STF); 270 ifc_free_unit(ifc, STFUNIT); 271 272 return (0); 273 } 274 275 static int 276 stfmodevent(mod, type, data) 277 module_t mod; 278 int type; 279 void *data; 280 { 281 282 switch (type) { 283 case MOD_LOAD: 284 stf_cloner = if_clone_advanced(stfname, 0, stf_clone_match, 285 stf_clone_create, stf_clone_destroy); 286 break; 287 case MOD_UNLOAD: 288 if_clone_detach(stf_cloner); 289 break; 290 default: 291 return (EOPNOTSUPP); 292 } 293 294 return (0); 295 } 296 297 static moduledata_t stf_mod = { 298 "if_stf", 299 stfmodevent, 300 0 301 }; 302 303 DECLARE_MODULE(if_stf, stf_mod, SI_SUB_PSEUDO, SI_ORDER_ANY); 304 305 static int 306 stf_encapcheck(m, off, proto, arg) 307 const struct mbuf *m; 308 int off; 309 int proto; 310 void *arg; 311 { 312 struct ip ip; 313 struct stf_softc *sc; 314 struct in_addr a, b, mask; 315 struct in6_addr addr6, mask6; 316 317 sc = (struct stf_softc *)arg; 318 if (sc == NULL) 319 return 0; 320 321 if ((STF2IFP(sc)->if_flags & IFF_UP) == 0) 322 return 0; 323 324 /* IFF_LINK0 means "no decapsulation" */ 325 if ((STF2IFP(sc)->if_flags & IFF_LINK0) != 0) 326 return 0; 327 328 if (proto != IPPROTO_IPV6) 329 return 0; 330 331 /* LINTED const cast */ 332 m_copydata((struct mbuf *)(uintptr_t)m, 0, sizeof(ip), (caddr_t)&ip); 333 334 if (ip.ip_v != 4) 335 return 0; 336 337 if (stf_getsrcifa6(STF2IFP(sc), &addr6, &mask6) != 0) 338 return (0); 339 340 /* 341 * check if IPv4 dst matches the IPv4 address derived from the 342 * local 6to4 address. 343 * success on: dst = 10.1.1.1, ia6->ia_addr = 2002:0a01:0101:... 344 */ 345 if (bcmp(GET_V4(&addr6), &ip.ip_dst, sizeof(ip.ip_dst)) != 0) 346 return 0; 347 348 /* 349 * check if IPv4 src matches the IPv4 address derived from the 350 * local 6to4 address masked by prefixmask. 351 * success on: src = 10.1.1.1, ia6->ia_addr = 2002:0a00:.../24 352 * fail on: src = 10.1.1.1, ia6->ia_addr = 2002:0b00:.../24 353 */ 354 bzero(&a, sizeof(a)); 355 bcopy(GET_V4(&addr6), &a, sizeof(a)); 356 bcopy(GET_V4(&mask6), &mask, sizeof(mask)); 357 a.s_addr &= mask.s_addr; 358 b = ip.ip_src; 359 b.s_addr &= mask.s_addr; 360 if (a.s_addr != b.s_addr) 361 return 0; 362 363 /* stf interface makes single side match only */ 364 return 32; 365 } 366 367 static int 368 stf_getsrcifa6(struct ifnet *ifp, struct in6_addr *addr, struct in6_addr *mask) 369 { 370 struct ifaddr *ia; 371 struct in_ifaddr *ia4; 372 struct in6_ifaddr *ia6; 373 struct sockaddr_in6 *sin6; 374 struct in_addr in; 375 376 if_addr_rlock(ifp); 377 TAILQ_FOREACH(ia, &ifp->if_addrhead, ifa_link) { 378 if (ia->ifa_addr->sa_family != AF_INET6) 379 continue; 380 sin6 = (struct sockaddr_in6 *)ia->ifa_addr; 381 if (!IN6_IS_ADDR_6TO4(&sin6->sin6_addr)) 382 continue; 383 384 bcopy(GET_V4(&sin6->sin6_addr), &in, sizeof(in)); 385 LIST_FOREACH(ia4, INADDR_HASH(in.s_addr), ia_hash) 386 if (ia4->ia_addr.sin_addr.s_addr == in.s_addr) 387 break; 388 if (ia4 == NULL) 389 continue; 390 391 ia6 = (struct in6_ifaddr *)ia; 392 393 *addr = sin6->sin6_addr; 394 *mask = ia6->ia_prefixmask.sin6_addr; 395 if_addr_runlock(ifp); 396 return (0); 397 } 398 if_addr_runlock(ifp); 399 400 return (ENOENT); 401 } 402 403 static int 404 stf_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst, 405 struct route *ro) 406 { 407 struct stf_softc *sc; 408 const struct sockaddr_in6 *dst6; 409 struct in_addr in4; 410 const void *ptr; 411 u_int8_t tos; 412 struct ip *ip; 413 struct ip6_hdr *ip6; 414 struct in6_addr addr6, mask6; 415 int error; 416 417 #ifdef MAC 418 error = mac_ifnet_check_transmit(ifp, m); 419 if (error) { 420 m_freem(m); 421 return (error); 422 } 423 #endif 424 425 sc = ifp->if_softc; 426 dst6 = (const struct sockaddr_in6 *)dst; 427 428 /* just in case */ 429 if ((ifp->if_flags & IFF_UP) == 0) { 430 m_freem(m); 431 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 432 return ENETDOWN; 433 } 434 435 /* 436 * If we don't have an ip4 address that match my inner ip6 address, 437 * we shouldn't generate output. Without this check, we'll end up 438 * using wrong IPv4 source. 439 */ 440 if (stf_getsrcifa6(ifp, &addr6, &mask6) != 0) { 441 m_freem(m); 442 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 443 return ENETDOWN; 444 } 445 446 if (m->m_len < sizeof(*ip6)) { 447 m = m_pullup(m, sizeof(*ip6)); 448 if (!m) { 449 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 450 return ENOBUFS; 451 } 452 } 453 ip6 = mtod(m, struct ip6_hdr *); 454 tos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; 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 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 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 u_int af = AF_INET6; 481 bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m); 482 } 483 484 M_PREPEND(m, sizeof(struct ip), M_NOWAIT); 485 if (m && m->m_len < sizeof(struct ip)) 486 m = m_pullup(m, sizeof(struct ip)); 487 if (m == NULL) { 488 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 489 return ENOBUFS; 490 } 491 ip = mtod(m, struct ip *); 492 493 bzero(ip, sizeof(*ip)); 494 495 bcopy(GET_V4(&addr6), &ip->ip_src, sizeof(ip->ip_src)); 496 bcopy(&in4, &ip->ip_dst, sizeof(ip->ip_dst)); 497 ip->ip_p = IPPROTO_IPV6; 498 ip->ip_ttl = ip_stf_ttl; 499 ip->ip_len = htons(m->m_pkthdr.len); 500 if (ifp->if_flags & IFF_LINK1) 501 ip_ecn_ingress(ECN_ALLOWED, &ip->ip_tos, &tos); 502 else 503 ip_ecn_ingress(ECN_NOCARE, &ip->ip_tos, &tos); 504 505 M_SETFIB(m, sc->sc_fibnum); 506 if_inc_counter(ifp, IFCOUNTER_OPACKETS, 1); 507 error = ip_output(m, NULL, NULL, 0, NULL, NULL); 508 509 return error; 510 } 511 512 static int 513 isrfc1918addr(in) 514 struct in_addr *in; 515 { 516 /* 517 * returns 1 if private address range: 518 * 10.0.0.0/8 172.16.0.0/12 192.168.0.0/16 519 */ 520 if (stf_permit_rfc1918 == 0 && ( 521 (ntohl(in->s_addr) & 0xff000000) >> 24 == 10 || 522 (ntohl(in->s_addr) & 0xfff00000) >> 16 == 172 * 256 + 16 || 523 (ntohl(in->s_addr) & 0xffff0000) >> 16 == 192 * 256 + 168)) 524 return 1; 525 526 return 0; 527 } 528 529 static int 530 stf_checkaddr4(sc, in, inifp) 531 struct stf_softc *sc; 532 struct in_addr *in; 533 struct ifnet *inifp; /* incoming interface */ 534 { 535 struct in_ifaddr *ia4; 536 537 /* 538 * reject packets with the following address: 539 * 224.0.0.0/4 0.0.0.0/8 127.0.0.0/8 255.0.0.0/8 540 */ 541 if (IN_MULTICAST(ntohl(in->s_addr))) 542 return -1; 543 switch ((ntohl(in->s_addr) & 0xff000000) >> 24) { 544 case 0: case 127: case 255: 545 return -1; 546 } 547 548 /* 549 * reject packets with private address range. 550 * (requirement from RFC3056 section 2 1st paragraph) 551 */ 552 if (isrfc1918addr(in)) 553 return -1; 554 555 /* 556 * reject packets with broadcast 557 */ 558 IN_IFADDR_RLOCK(); 559 TAILQ_FOREACH(ia4, &V_in_ifaddrhead, ia_link) { 560 if ((ia4->ia_ifa.ifa_ifp->if_flags & IFF_BROADCAST) == 0) 561 continue; 562 if (in->s_addr == ia4->ia_broadaddr.sin_addr.s_addr) { 563 IN_IFADDR_RUNLOCK(); 564 return -1; 565 } 566 } 567 IN_IFADDR_RUNLOCK(); 568 569 /* 570 * perform ingress filter 571 */ 572 if (sc && (STF2IFP(sc)->if_flags & IFF_LINK2) == 0 && inifp) { 573 struct sockaddr_in sin; 574 struct rtentry *rt; 575 576 bzero(&sin, sizeof(sin)); 577 sin.sin_family = AF_INET; 578 sin.sin_len = sizeof(struct sockaddr_in); 579 sin.sin_addr = *in; 580 rt = rtalloc1_fib((struct sockaddr *)&sin, 0, 581 0UL, sc->sc_fibnum); 582 if (!rt || rt->rt_ifp != inifp) { 583 #if 0 584 log(LOG_WARNING, "%s: packet from 0x%x dropped " 585 "due to ingress filter\n", if_name(STF2IFP(sc)), 586 (u_int32_t)ntohl(sin.sin_addr.s_addr)); 587 #endif 588 if (rt) 589 RTFREE_LOCKED(rt); 590 return -1; 591 } 592 RTFREE_LOCKED(rt); 593 } 594 595 return 0; 596 } 597 598 static int 599 stf_checkaddr6(sc, in6, inifp) 600 struct stf_softc *sc; 601 struct in6_addr *in6; 602 struct ifnet *inifp; /* incoming interface */ 603 { 604 /* 605 * check 6to4 addresses 606 */ 607 if (IN6_IS_ADDR_6TO4(in6)) { 608 struct in_addr in4; 609 bcopy(GET_V4(in6), &in4, sizeof(in4)); 610 return stf_checkaddr4(sc, &in4, inifp); 611 } 612 613 /* 614 * reject anything that look suspicious. the test is implemented 615 * in ip6_input too, but we check here as well to 616 * (1) reject bad packets earlier, and 617 * (2) to be safe against future ip6_input change. 618 */ 619 if (IN6_IS_ADDR_V4COMPAT(in6) || IN6_IS_ADDR_V4MAPPED(in6)) 620 return -1; 621 622 return 0; 623 } 624 625 int 626 in_stf_input(struct mbuf **mp, int *offp, int proto) 627 { 628 struct stf_softc *sc; 629 struct ip *ip; 630 struct ip6_hdr *ip6; 631 struct mbuf *m; 632 u_int8_t otos, itos; 633 struct ifnet *ifp; 634 int off; 635 636 m = *mp; 637 off = *offp; 638 639 if (proto != IPPROTO_IPV6) { 640 m_freem(m); 641 return (IPPROTO_DONE); 642 } 643 644 ip = mtod(m, struct ip *); 645 646 sc = (struct stf_softc *)encap_getarg(m); 647 648 if (sc == NULL || (STF2IFP(sc)->if_flags & IFF_UP) == 0) { 649 m_freem(m); 650 return (IPPROTO_DONE); 651 } 652 653 ifp = STF2IFP(sc); 654 655 #ifdef MAC 656 mac_ifnet_create_mbuf(ifp, m); 657 #endif 658 659 /* 660 * perform sanity check against outer src/dst. 661 * for source, perform ingress filter as well. 662 */ 663 if (stf_checkaddr4(sc, &ip->ip_dst, NULL) < 0 || 664 stf_checkaddr4(sc, &ip->ip_src, m->m_pkthdr.rcvif) < 0) { 665 m_freem(m); 666 return (IPPROTO_DONE); 667 } 668 669 otos = ip->ip_tos; 670 m_adj(m, off); 671 672 if (m->m_len < sizeof(*ip6)) { 673 m = m_pullup(m, sizeof(*ip6)); 674 if (!m) 675 return (IPPROTO_DONE); 676 } 677 ip6 = mtod(m, struct ip6_hdr *); 678 679 /* 680 * perform sanity check against inner src/dst. 681 * for source, perform ingress filter as well. 682 */ 683 if (stf_checkaddr6(sc, &ip6->ip6_dst, NULL) < 0 || 684 stf_checkaddr6(sc, &ip6->ip6_src, m->m_pkthdr.rcvif) < 0) { 685 m_freem(m); 686 return (IPPROTO_DONE); 687 } 688 689 itos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; 690 if ((ifp->if_flags & IFF_LINK1) != 0) 691 ip_ecn_egress(ECN_ALLOWED, &otos, &itos); 692 else 693 ip_ecn_egress(ECN_NOCARE, &otos, &itos); 694 ip6->ip6_flow &= ~htonl(0xff << 20); 695 ip6->ip6_flow |= htonl((u_int32_t)itos << 20); 696 697 m->m_pkthdr.rcvif = ifp; 698 699 if (bpf_peers_present(ifp->if_bpf)) { 700 /* 701 * We need to prepend the address family as 702 * a four byte field. Cons up a dummy header 703 * to pacify bpf. This is safe because bpf 704 * will only read from the mbuf (i.e., it won't 705 * try to free it or keep a pointer a to it). 706 */ 707 u_int32_t af = AF_INET6; 708 bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m); 709 } 710 711 /* 712 * Put the packet to the network layer input queue according to the 713 * specified address family. 714 * See net/if_gif.c for possible issues with packet processing 715 * reorder due to extra queueing. 716 */ 717 if_inc_counter(ifp, IFCOUNTER_IPACKETS, 1); 718 if_inc_counter(ifp, IFCOUNTER_IBYTES, m->m_pkthdr.len); 719 M_SETFIB(m, ifp->if_fib); 720 netisr_dispatch(NETISR_IPV6, m); 721 return (IPPROTO_DONE); 722 } 723 724 static int 725 stf_ioctl(ifp, cmd, data) 726 struct ifnet *ifp; 727 u_long cmd; 728 caddr_t data; 729 { 730 struct ifaddr *ifa; 731 struct ifreq *ifr; 732 struct sockaddr_in6 *sin6; 733 struct in_addr addr; 734 int error, mtu; 735 736 error = 0; 737 switch (cmd) { 738 case SIOCSIFADDR: 739 ifa = (struct ifaddr *)data; 740 if (ifa == NULL || ifa->ifa_addr->sa_family != AF_INET6) { 741 error = EAFNOSUPPORT; 742 break; 743 } 744 sin6 = (struct sockaddr_in6 *)ifa->ifa_addr; 745 if (!IN6_IS_ADDR_6TO4(&sin6->sin6_addr)) { 746 error = EINVAL; 747 break; 748 } 749 bcopy(GET_V4(&sin6->sin6_addr), &addr, sizeof(addr)); 750 if (isrfc1918addr(&addr)) { 751 error = EINVAL; 752 break; 753 } 754 755 ifp->if_flags |= IFF_UP; 756 break; 757 758 case SIOCADDMULTI: 759 case SIOCDELMULTI: 760 ifr = (struct ifreq *)data; 761 if (ifr && ifr->ifr_addr.sa_family == AF_INET6) 762 ; 763 else 764 error = EAFNOSUPPORT; 765 break; 766 767 case SIOCGIFMTU: 768 break; 769 770 case SIOCSIFMTU: 771 ifr = (struct ifreq *)data; 772 mtu = ifr->ifr_mtu; 773 /* RFC 4213 3.2 ideal world MTU */ 774 if (mtu < IPV6_MINMTU || mtu > IF_MAXMTU - 20) 775 return (EINVAL); 776 ifp->if_mtu = mtu; 777 break; 778 779 default: 780 error = EINVAL; 781 break; 782 } 783 784 return error; 785 } 786