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 <sys/param.h> 78 #include <sys/systm.h> 79 #include <sys/socket.h> 80 #include <sys/sockio.h> 81 #include <sys/mbuf.h> 82 #include <sys/errno.h> 83 #include <sys/kernel.h> 84 #include <sys/lock.h> 85 #include <sys/module.h> 86 #include <sys/protosw.h> 87 #include <sys/proc.h> 88 #include <sys/queue.h> 89 #include <sys/rmlock.h> 90 #include <sys/sysctl.h> 91 #include <machine/cpu.h> 92 93 #include <sys/malloc.h> 94 95 #include <net/if.h> 96 #include <net/if_var.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/vnet.h> 102 103 #include <netinet/in.h> 104 #include <netinet/in_fib.h> 105 #include <netinet/in_systm.h> 106 #include <netinet/ip.h> 107 #include <netinet/ip_var.h> 108 #include <netinet/in_var.h> 109 110 #include <netinet/ip6.h> 111 #include <netinet6/ip6_var.h> 112 #include <netinet6/in6_var.h> 113 #include <netinet/ip_ecn.h> 114 115 #include <netinet/ip_encap.h> 116 117 #include <machine/stdarg.h> 118 119 #include <net/bpf.h> 120 121 #include <security/mac/mac_framework.h> 122 123 SYSCTL_DECL(_net_link); 124 static SYSCTL_NODE(_net_link, IFT_STF, stf, CTLFLAG_RW, 0, "6to4 Interface"); 125 126 static int stf_permit_rfc1918 = 0; 127 SYSCTL_INT(_net_link_stf, OID_AUTO, permit_rfc1918, CTLFLAG_RWTUN, 128 &stf_permit_rfc1918, 0, "Permit the use of private IPv4 addresses"); 129 130 #define STFUNIT 0 131 132 #define IN6_IS_ADDR_6TO4(x) (ntohs((x)->s6_addr16[0]) == 0x2002) 133 134 /* 135 * XXX: Return a pointer with 16-bit aligned. Don't cast it to 136 * struct in_addr *; use bcopy() instead. 137 */ 138 #define GET_V4(x) (&(x)->s6_addr16[1]) 139 140 struct stf_softc { 141 struct ifnet *sc_ifp; 142 struct mtx sc_ro_mtx; 143 u_int sc_fibnum; 144 const struct encaptab *encap_cookie; 145 }; 146 #define STF2IFP(sc) ((sc)->sc_ifp) 147 148 static const char stfname[] = "stf"; 149 150 /* 151 * Note that mutable fields in the softc are not currently locked. 152 * We do lock sc_ro in stf_output though. 153 */ 154 static MALLOC_DEFINE(M_STF, stfname, "6to4 Tunnel Interface"); 155 static const int ip_stf_ttl = 40; 156 157 extern struct domain inetdomain; 158 static int in_stf_input(struct mbuf **, int *, int); 159 static 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(module_t mod, int type, void *data) 277 { 278 279 switch (type) { 280 case MOD_LOAD: 281 stf_cloner = if_clone_advanced(stfname, 0, stf_clone_match, 282 stf_clone_create, stf_clone_destroy); 283 break; 284 case MOD_UNLOAD: 285 if_clone_detach(stf_cloner); 286 break; 287 default: 288 return (EOPNOTSUPP); 289 } 290 291 return (0); 292 } 293 294 static moduledata_t stf_mod = { 295 "if_stf", 296 stfmodevent, 297 0 298 }; 299 300 DECLARE_MODULE(if_stf, stf_mod, SI_SUB_PSEUDO, SI_ORDER_ANY); 301 302 static int 303 stf_encapcheck(const struct mbuf *m, int off, int proto, void *arg) 304 { 305 struct ip ip; 306 struct stf_softc *sc; 307 struct in_addr a, b, mask; 308 struct in6_addr addr6, mask6; 309 310 sc = (struct stf_softc *)arg; 311 if (sc == NULL) 312 return 0; 313 314 if ((STF2IFP(sc)->if_flags & IFF_UP) == 0) 315 return 0; 316 317 /* IFF_LINK0 means "no decapsulation" */ 318 if ((STF2IFP(sc)->if_flags & IFF_LINK0) != 0) 319 return 0; 320 321 if (proto != IPPROTO_IPV6) 322 return 0; 323 324 /* LINTED const cast */ 325 m_copydata((struct mbuf *)(uintptr_t)m, 0, sizeof(ip), (caddr_t)&ip); 326 327 if (ip.ip_v != 4) 328 return 0; 329 330 if (stf_getsrcifa6(STF2IFP(sc), &addr6, &mask6) != 0) 331 return (0); 332 333 /* 334 * check if IPv4 dst matches the IPv4 address derived from the 335 * local 6to4 address. 336 * success on: dst = 10.1.1.1, ia6->ia_addr = 2002:0a01:0101:... 337 */ 338 if (bcmp(GET_V4(&addr6), &ip.ip_dst, sizeof(ip.ip_dst)) != 0) 339 return 0; 340 341 /* 342 * check if IPv4 src matches the IPv4 address derived from the 343 * local 6to4 address masked by prefixmask. 344 * success on: src = 10.1.1.1, ia6->ia_addr = 2002:0a00:.../24 345 * fail on: src = 10.1.1.1, ia6->ia_addr = 2002:0b00:.../24 346 */ 347 bzero(&a, sizeof(a)); 348 bcopy(GET_V4(&addr6), &a, sizeof(a)); 349 bcopy(GET_V4(&mask6), &mask, sizeof(mask)); 350 a.s_addr &= mask.s_addr; 351 b = ip.ip_src; 352 b.s_addr &= mask.s_addr; 353 if (a.s_addr != b.s_addr) 354 return 0; 355 356 /* stf interface makes single side match only */ 357 return 32; 358 } 359 360 static int 361 stf_getsrcifa6(struct ifnet *ifp, struct in6_addr *addr, struct in6_addr *mask) 362 { 363 struct ifaddr *ia; 364 struct in_ifaddr *ia4; 365 struct in6_ifaddr *ia6; 366 struct sockaddr_in6 *sin6; 367 struct in_addr in; 368 369 if_addr_rlock(ifp); 370 TAILQ_FOREACH(ia, &ifp->if_addrhead, ifa_link) { 371 if (ia->ifa_addr->sa_family != AF_INET6) 372 continue; 373 sin6 = (struct sockaddr_in6 *)ia->ifa_addr; 374 if (!IN6_IS_ADDR_6TO4(&sin6->sin6_addr)) 375 continue; 376 377 bcopy(GET_V4(&sin6->sin6_addr), &in, sizeof(in)); 378 LIST_FOREACH(ia4, INADDR_HASH(in.s_addr), ia_hash) 379 if (ia4->ia_addr.sin_addr.s_addr == in.s_addr) 380 break; 381 if (ia4 == NULL) 382 continue; 383 384 ia6 = (struct in6_ifaddr *)ia; 385 386 *addr = sin6->sin6_addr; 387 *mask = ia6->ia_prefixmask.sin6_addr; 388 if_addr_runlock(ifp); 389 return (0); 390 } 391 if_addr_runlock(ifp); 392 393 return (ENOENT); 394 } 395 396 static int 397 stf_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst, 398 struct route *ro) 399 { 400 struct stf_softc *sc; 401 const struct sockaddr_in6 *dst6; 402 struct in_addr in4; 403 const void *ptr; 404 u_int8_t tos; 405 struct ip *ip; 406 struct ip6_hdr *ip6; 407 struct in6_addr addr6, mask6; 408 int error; 409 410 #ifdef MAC 411 error = mac_ifnet_check_transmit(ifp, m); 412 if (error) { 413 m_freem(m); 414 return (error); 415 } 416 #endif 417 418 sc = ifp->if_softc; 419 dst6 = (const struct sockaddr_in6 *)dst; 420 421 /* just in case */ 422 if ((ifp->if_flags & IFF_UP) == 0) { 423 m_freem(m); 424 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 425 return ENETDOWN; 426 } 427 428 /* 429 * If we don't have an ip4 address that match my inner ip6 address, 430 * we shouldn't generate output. Without this check, we'll end up 431 * using wrong IPv4 source. 432 */ 433 if (stf_getsrcifa6(ifp, &addr6, &mask6) != 0) { 434 m_freem(m); 435 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 436 return ENETDOWN; 437 } 438 439 if (m->m_len < sizeof(*ip6)) { 440 m = m_pullup(m, sizeof(*ip6)); 441 if (!m) { 442 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 443 return ENOBUFS; 444 } 445 } 446 ip6 = mtod(m, struct ip6_hdr *); 447 tos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; 448 449 /* 450 * Pickup the right outer dst addr from the list of candidates. 451 * ip6_dst has priority as it may be able to give us shorter IPv4 hops. 452 */ 453 ptr = NULL; 454 if (IN6_IS_ADDR_6TO4(&ip6->ip6_dst)) 455 ptr = GET_V4(&ip6->ip6_dst); 456 else if (IN6_IS_ADDR_6TO4(&dst6->sin6_addr)) 457 ptr = GET_V4(&dst6->sin6_addr); 458 else { 459 m_freem(m); 460 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 461 return ENETUNREACH; 462 } 463 bcopy(ptr, &in4, sizeof(in4)); 464 465 if (bpf_peers_present(ifp->if_bpf)) { 466 /* 467 * We need to prepend the address family as 468 * a four byte field. Cons up a dummy header 469 * to pacify bpf. This is safe because bpf 470 * will only read from the mbuf (i.e., it won't 471 * try to free it or keep a pointer a to it). 472 */ 473 u_int af = AF_INET6; 474 bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m); 475 } 476 477 M_PREPEND(m, sizeof(struct ip), M_NOWAIT); 478 if (m == NULL) { 479 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 480 return ENOBUFS; 481 } 482 ip = mtod(m, struct ip *); 483 484 bzero(ip, sizeof(*ip)); 485 486 bcopy(GET_V4(&addr6), &ip->ip_src, sizeof(ip->ip_src)); 487 bcopy(&in4, &ip->ip_dst, sizeof(ip->ip_dst)); 488 ip->ip_p = IPPROTO_IPV6; 489 ip->ip_ttl = ip_stf_ttl; 490 ip->ip_len = htons(m->m_pkthdr.len); 491 if (ifp->if_flags & IFF_LINK1) 492 ip_ecn_ingress(ECN_ALLOWED, &ip->ip_tos, &tos); 493 else 494 ip_ecn_ingress(ECN_NOCARE, &ip->ip_tos, &tos); 495 496 M_SETFIB(m, sc->sc_fibnum); 497 if_inc_counter(ifp, IFCOUNTER_OPACKETS, 1); 498 error = ip_output(m, NULL, NULL, 0, NULL, NULL); 499 500 return error; 501 } 502 503 static int 504 isrfc1918addr(struct in_addr *in) 505 { 506 /* 507 * returns 1 if private address range: 508 * 10.0.0.0/8 172.16.0.0/12 192.168.0.0/16 509 */ 510 if (stf_permit_rfc1918 == 0 && ( 511 (ntohl(in->s_addr) & 0xff000000) >> 24 == 10 || 512 (ntohl(in->s_addr) & 0xfff00000) >> 16 == 172 * 256 + 16 || 513 (ntohl(in->s_addr) & 0xffff0000) >> 16 == 192 * 256 + 168)) 514 return 1; 515 516 return 0; 517 } 518 519 static int 520 stf_checkaddr4(struct stf_softc *sc, struct in_addr *in, struct ifnet *inifp) 521 { 522 struct rm_priotracker in_ifa_tracker; 523 struct in_ifaddr *ia4; 524 525 /* 526 * reject packets with the following address: 527 * 224.0.0.0/4 0.0.0.0/8 127.0.0.0/8 255.0.0.0/8 528 */ 529 if (IN_MULTICAST(ntohl(in->s_addr))) 530 return -1; 531 switch ((ntohl(in->s_addr) & 0xff000000) >> 24) { 532 case 0: case 127: case 255: 533 return -1; 534 } 535 536 /* 537 * reject packets with private address range. 538 * (requirement from RFC3056 section 2 1st paragraph) 539 */ 540 if (isrfc1918addr(in)) 541 return -1; 542 543 /* 544 * reject packets with broadcast 545 */ 546 IN_IFADDR_RLOCK(&in_ifa_tracker); 547 TAILQ_FOREACH(ia4, &V_in_ifaddrhead, ia_link) { 548 if ((ia4->ia_ifa.ifa_ifp->if_flags & IFF_BROADCAST) == 0) 549 continue; 550 if (in->s_addr == ia4->ia_broadaddr.sin_addr.s_addr) { 551 IN_IFADDR_RUNLOCK(&in_ifa_tracker); 552 return -1; 553 } 554 } 555 IN_IFADDR_RUNLOCK(&in_ifa_tracker); 556 557 /* 558 * perform ingress filter 559 */ 560 if (sc && (STF2IFP(sc)->if_flags & IFF_LINK2) == 0 && inifp) { 561 struct nhop4_basic nh4; 562 563 if (fib4_lookup_nh_basic(sc->sc_fibnum, *in, 0, 0, &nh4) != 0) 564 return (-1); 565 566 if (nh4.nh_ifp != inifp) 567 return (-1); 568 } 569 570 return 0; 571 } 572 573 static int 574 stf_checkaddr6(struct stf_softc *sc, struct in6_addr *in6, struct ifnet *inifp) 575 { 576 /* 577 * check 6to4 addresses 578 */ 579 if (IN6_IS_ADDR_6TO4(in6)) { 580 struct in_addr in4; 581 bcopy(GET_V4(in6), &in4, sizeof(in4)); 582 return stf_checkaddr4(sc, &in4, inifp); 583 } 584 585 /* 586 * reject anything that look suspicious. the test is implemented 587 * in ip6_input too, but we check here as well to 588 * (1) reject bad packets earlier, and 589 * (2) to be safe against future ip6_input change. 590 */ 591 if (IN6_IS_ADDR_V4COMPAT(in6) || IN6_IS_ADDR_V4MAPPED(in6)) 592 return -1; 593 594 return 0; 595 } 596 597 static int 598 in_stf_input(struct mbuf **mp, int *offp, int proto) 599 { 600 struct stf_softc *sc; 601 struct ip *ip; 602 struct ip6_hdr *ip6; 603 struct mbuf *m; 604 u_int8_t otos, itos; 605 struct ifnet *ifp; 606 int off; 607 608 m = *mp; 609 off = *offp; 610 611 if (proto != IPPROTO_IPV6) { 612 m_freem(m); 613 return (IPPROTO_DONE); 614 } 615 616 ip = mtod(m, struct ip *); 617 618 sc = (struct stf_softc *)encap_getarg(m); 619 620 if (sc == NULL || (STF2IFP(sc)->if_flags & IFF_UP) == 0) { 621 m_freem(m); 622 return (IPPROTO_DONE); 623 } 624 625 ifp = STF2IFP(sc); 626 627 #ifdef MAC 628 mac_ifnet_create_mbuf(ifp, m); 629 #endif 630 631 /* 632 * perform sanity check against outer src/dst. 633 * for source, perform ingress filter as well. 634 */ 635 if (stf_checkaddr4(sc, &ip->ip_dst, NULL) < 0 || 636 stf_checkaddr4(sc, &ip->ip_src, m->m_pkthdr.rcvif) < 0) { 637 m_freem(m); 638 return (IPPROTO_DONE); 639 } 640 641 otos = ip->ip_tos; 642 m_adj(m, off); 643 644 if (m->m_len < sizeof(*ip6)) { 645 m = m_pullup(m, sizeof(*ip6)); 646 if (!m) 647 return (IPPROTO_DONE); 648 } 649 ip6 = mtod(m, struct ip6_hdr *); 650 651 /* 652 * perform sanity check against inner src/dst. 653 * for source, perform ingress filter as well. 654 */ 655 if (stf_checkaddr6(sc, &ip6->ip6_dst, NULL) < 0 || 656 stf_checkaddr6(sc, &ip6->ip6_src, m->m_pkthdr.rcvif) < 0) { 657 m_freem(m); 658 return (IPPROTO_DONE); 659 } 660 661 itos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; 662 if ((ifp->if_flags & IFF_LINK1) != 0) 663 ip_ecn_egress(ECN_ALLOWED, &otos, &itos); 664 else 665 ip_ecn_egress(ECN_NOCARE, &otos, &itos); 666 ip6->ip6_flow &= ~htonl(0xff << 20); 667 ip6->ip6_flow |= htonl((u_int32_t)itos << 20); 668 669 m->m_pkthdr.rcvif = ifp; 670 671 if (bpf_peers_present(ifp->if_bpf)) { 672 /* 673 * We need to prepend the address family as 674 * a four byte field. Cons up a dummy header 675 * to pacify bpf. This is safe because bpf 676 * will only read from the mbuf (i.e., it won't 677 * try to free it or keep a pointer a to it). 678 */ 679 u_int32_t af = AF_INET6; 680 bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m); 681 } 682 683 /* 684 * Put the packet to the network layer input queue according to the 685 * specified address family. 686 * See net/if_gif.c for possible issues with packet processing 687 * reorder due to extra queueing. 688 */ 689 if_inc_counter(ifp, IFCOUNTER_IPACKETS, 1); 690 if_inc_counter(ifp, IFCOUNTER_IBYTES, m->m_pkthdr.len); 691 M_SETFIB(m, ifp->if_fib); 692 netisr_dispatch(NETISR_IPV6, m); 693 return (IPPROTO_DONE); 694 } 695 696 static int 697 stf_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data) 698 { 699 struct ifaddr *ifa; 700 struct ifreq *ifr; 701 struct sockaddr_in6 *sin6; 702 struct in_addr addr; 703 int error, mtu; 704 705 error = 0; 706 switch (cmd) { 707 case SIOCSIFADDR: 708 ifa = (struct ifaddr *)data; 709 if (ifa == NULL || ifa->ifa_addr->sa_family != AF_INET6) { 710 error = EAFNOSUPPORT; 711 break; 712 } 713 sin6 = (struct sockaddr_in6 *)ifa->ifa_addr; 714 if (!IN6_IS_ADDR_6TO4(&sin6->sin6_addr)) { 715 error = EINVAL; 716 break; 717 } 718 bcopy(GET_V4(&sin6->sin6_addr), &addr, sizeof(addr)); 719 if (isrfc1918addr(&addr)) { 720 error = EINVAL; 721 break; 722 } 723 724 ifp->if_flags |= IFF_UP; 725 break; 726 727 case SIOCADDMULTI: 728 case SIOCDELMULTI: 729 ifr = (struct ifreq *)data; 730 if (ifr && ifr->ifr_addr.sa_family == AF_INET6) 731 ; 732 else 733 error = EAFNOSUPPORT; 734 break; 735 736 case SIOCGIFMTU: 737 break; 738 739 case SIOCSIFMTU: 740 ifr = (struct ifreq *)data; 741 mtu = ifr->ifr_mtu; 742 /* RFC 4213 3.2 ideal world MTU */ 743 if (mtu < IPV6_MINMTU || mtu > IF_MAXMTU - 20) 744 return (EINVAL); 745 ifp->if_mtu = mtu; 746 break; 747 748 default: 749 error = EINVAL; 750 break; 751 } 752 753 return error; 754 } 755