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_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 #include <security/mac/mac_framework.h> 121 122 SYSCTL_DECL(_net_link); 123 static SYSCTL_NODE(_net_link, IFT_STF, stf, CTLFLAG_RW, 0, "6to4 Interface"); 124 125 static int stf_permit_rfc1918 = 0; 126 SYSCTL_INT(_net_link_stf, OID_AUTO, permit_rfc1918, CTLFLAG_RWTUN, 127 &stf_permit_rfc1918, 0, "Permit the use of private IPv4 addresses"); 128 129 #define STFUNIT 0 130 131 #define IN6_IS_ADDR_6TO4(x) (ntohs((x)->s6_addr16[0]) == 0x2002) 132 133 /* 134 * XXX: Return a pointer with 16-bit aligned. Don't cast it to 135 * struct in_addr *; use bcopy() instead. 136 */ 137 #define GET_V4(x) (&(x)->s6_addr16[1]) 138 139 struct stf_softc { 140 struct ifnet *sc_ifp; 141 struct mtx sc_ro_mtx; 142 u_int sc_fibnum; 143 const struct encaptab *encap_cookie; 144 }; 145 #define STF2IFP(sc) ((sc)->sc_ifp) 146 147 static const char stfname[] = "stf"; 148 149 /* 150 * Note that mutable fields in the softc are not currently locked. 151 * We do lock sc_ro in stf_output though. 152 */ 153 static MALLOC_DEFINE(M_STF, stfname, "6to4 Tunnel Interface"); 154 static const int ip_stf_ttl = 40; 155 156 extern struct domain inetdomain; 157 static int in_stf_input(struct mbuf **, int *, int); 158 static struct protosw in_stf_protosw = { 159 .pr_type = SOCK_RAW, 160 .pr_domain = &inetdomain, 161 .pr_protocol = IPPROTO_IPV6, 162 .pr_flags = PR_ATOMIC|PR_ADDR, 163 .pr_input = in_stf_input, 164 .pr_output = rip_output, 165 .pr_ctloutput = rip_ctloutput, 166 .pr_usrreqs = &rip_usrreqs 167 }; 168 169 static char *stfnames[] = {"stf0", "stf", "6to4", NULL}; 170 171 static int stfmodevent(module_t, int, void *); 172 static int stf_encapcheck(const struct mbuf *, int, int, void *); 173 static int stf_getsrcifa6(struct ifnet *, struct in6_addr *, struct in6_addr *); 174 static int stf_output(struct ifnet *, struct mbuf *, const struct sockaddr *, 175 struct route *); 176 static int isrfc1918addr(struct in_addr *); 177 static int stf_checkaddr4(struct stf_softc *, struct in_addr *, 178 struct ifnet *); 179 static int stf_checkaddr6(struct stf_softc *, struct in6_addr *, 180 struct ifnet *); 181 static int stf_ioctl(struct ifnet *, u_long, caddr_t); 182 183 static int stf_clone_match(struct if_clone *, const char *); 184 static int stf_clone_create(struct if_clone *, char *, size_t, caddr_t); 185 static int stf_clone_destroy(struct if_clone *, struct ifnet *); 186 static struct if_clone *stf_cloner; 187 188 static int 189 stf_clone_match(struct if_clone *ifc, const char *name) 190 { 191 int i; 192 193 for(i = 0; stfnames[i] != NULL; i++) { 194 if (strcmp(stfnames[i], name) == 0) 195 return (1); 196 } 197 198 return (0); 199 } 200 201 static int 202 stf_clone_create(struct if_clone *ifc, char *name, size_t len, caddr_t params) 203 { 204 int err, unit; 205 struct stf_softc *sc; 206 struct ifnet *ifp; 207 208 /* 209 * We can only have one unit, but since unit allocation is 210 * already locked, we use it to keep from allocating extra 211 * interfaces. 212 */ 213 unit = STFUNIT; 214 err = ifc_alloc_unit(ifc, &unit); 215 if (err != 0) 216 return (err); 217 218 sc = malloc(sizeof(struct stf_softc), M_STF, M_WAITOK | M_ZERO); 219 ifp = STF2IFP(sc) = if_alloc(IFT_STF); 220 if (ifp == NULL) { 221 free(sc, M_STF); 222 ifc_free_unit(ifc, unit); 223 return (ENOSPC); 224 } 225 ifp->if_softc = sc; 226 sc->sc_fibnum = curthread->td_proc->p_fibnum; 227 228 /* 229 * Set the name manually rather then using if_initname because 230 * we don't conform to the default naming convention for interfaces. 231 */ 232 strlcpy(ifp->if_xname, name, IFNAMSIZ); 233 ifp->if_dname = stfname; 234 ifp->if_dunit = IF_DUNIT_NONE; 235 236 mtx_init(&(sc)->sc_ro_mtx, "stf ro", NULL, MTX_DEF); 237 sc->encap_cookie = encap_attach_func(AF_INET, IPPROTO_IPV6, 238 stf_encapcheck, &in_stf_protosw, sc); 239 if (sc->encap_cookie == NULL) { 240 if_printf(ifp, "attach failed\n"); 241 free(sc, M_STF); 242 ifc_free_unit(ifc, unit); 243 return (ENOMEM); 244 } 245 246 ifp->if_mtu = IPV6_MMTU; 247 ifp->if_ioctl = stf_ioctl; 248 ifp->if_output = stf_output; 249 ifp->if_snd.ifq_maxlen = ifqmaxlen; 250 if_attach(ifp); 251 bpfattach(ifp, DLT_NULL, sizeof(u_int32_t)); 252 return (0); 253 } 254 255 static int 256 stf_clone_destroy(struct if_clone *ifc, struct ifnet *ifp) 257 { 258 struct stf_softc *sc = ifp->if_softc; 259 int err; 260 261 err = encap_detach(sc->encap_cookie); 262 KASSERT(err == 0, ("Unexpected error detaching encap_cookie")); 263 mtx_destroy(&(sc)->sc_ro_mtx); 264 bpfdetach(ifp); 265 if_detach(ifp); 266 if_free(ifp); 267 268 free(sc, M_STF); 269 ifc_free_unit(ifc, STFUNIT); 270 271 return (0); 272 } 273 274 static int 275 stfmodevent(module_t mod, int type, void *data) 276 { 277 278 switch (type) { 279 case MOD_LOAD: 280 stf_cloner = if_clone_advanced(stfname, 0, stf_clone_match, 281 stf_clone_create, stf_clone_destroy); 282 break; 283 case MOD_UNLOAD: 284 if_clone_detach(stf_cloner); 285 break; 286 default: 287 return (EOPNOTSUPP); 288 } 289 290 return (0); 291 } 292 293 static moduledata_t stf_mod = { 294 "if_stf", 295 stfmodevent, 296 0 297 }; 298 299 DECLARE_MODULE(if_stf, stf_mod, SI_SUB_PSEUDO, SI_ORDER_ANY); 300 301 static int 302 stf_encapcheck(const struct mbuf *m, int off, int proto, void *arg) 303 { 304 struct ip ip; 305 struct stf_softc *sc; 306 struct in_addr a, b, mask; 307 struct in6_addr addr6, mask6; 308 309 sc = (struct stf_softc *)arg; 310 if (sc == NULL) 311 return 0; 312 313 if ((STF2IFP(sc)->if_flags & IFF_UP) == 0) 314 return 0; 315 316 /* IFF_LINK0 means "no decapsulation" */ 317 if ((STF2IFP(sc)->if_flags & IFF_LINK0) != 0) 318 return 0; 319 320 if (proto != IPPROTO_IPV6) 321 return 0; 322 323 /* LINTED const cast */ 324 m_copydata((struct mbuf *)(uintptr_t)m, 0, sizeof(ip), (caddr_t)&ip); 325 326 if (ip.ip_v != 4) 327 return 0; 328 329 if (stf_getsrcifa6(STF2IFP(sc), &addr6, &mask6) != 0) 330 return (0); 331 332 /* 333 * check if IPv4 dst matches the IPv4 address derived from the 334 * local 6to4 address. 335 * success on: dst = 10.1.1.1, ia6->ia_addr = 2002:0a01:0101:... 336 */ 337 if (bcmp(GET_V4(&addr6), &ip.ip_dst, 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(&addr6), &a, sizeof(a)); 348 bcopy(GET_V4(&mask6), &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 int 360 stf_getsrcifa6(struct ifnet *ifp, struct in6_addr *addr, struct in6_addr *mask) 361 { 362 struct ifaddr *ia; 363 struct in_ifaddr *ia4; 364 struct in6_ifaddr *ia6; 365 struct sockaddr_in6 *sin6; 366 struct in_addr in; 367 368 if_addr_rlock(ifp); 369 TAILQ_FOREACH(ia, &ifp->if_addrhead, ifa_link) { 370 if (ia->ifa_addr->sa_family != AF_INET6) 371 continue; 372 sin6 = (struct sockaddr_in6 *)ia->ifa_addr; 373 if (!IN6_IS_ADDR_6TO4(&sin6->sin6_addr)) 374 continue; 375 376 bcopy(GET_V4(&sin6->sin6_addr), &in, sizeof(in)); 377 LIST_FOREACH(ia4, INADDR_HASH(in.s_addr), ia_hash) 378 if (ia4->ia_addr.sin_addr.s_addr == in.s_addr) 379 break; 380 if (ia4 == NULL) 381 continue; 382 383 ia6 = (struct in6_ifaddr *)ia; 384 385 *addr = sin6->sin6_addr; 386 *mask = ia6->ia_prefixmask.sin6_addr; 387 if_addr_runlock(ifp); 388 return (0); 389 } 390 if_addr_runlock(ifp); 391 392 return (ENOENT); 393 } 394 395 static int 396 stf_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst, 397 struct route *ro) 398 { 399 struct stf_softc *sc; 400 const struct sockaddr_in6 *dst6; 401 struct in_addr in4; 402 const void *ptr; 403 u_int8_t tos; 404 struct ip *ip; 405 struct ip6_hdr *ip6; 406 struct in6_addr addr6, mask6; 407 int error; 408 409 #ifdef MAC 410 error = mac_ifnet_check_transmit(ifp, m); 411 if (error) { 412 m_freem(m); 413 return (error); 414 } 415 #endif 416 417 sc = ifp->if_softc; 418 dst6 = (const struct sockaddr_in6 *)dst; 419 420 /* just in case */ 421 if ((ifp->if_flags & IFF_UP) == 0) { 422 m_freem(m); 423 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 424 return ENETDOWN; 425 } 426 427 /* 428 * If we don't have an ip4 address that match my inner ip6 address, 429 * we shouldn't generate output. Without this check, we'll end up 430 * using wrong IPv4 source. 431 */ 432 if (stf_getsrcifa6(ifp, &addr6, &mask6) != 0) { 433 m_freem(m); 434 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 435 return ENETDOWN; 436 } 437 438 if (m->m_len < sizeof(*ip6)) { 439 m = m_pullup(m, sizeof(*ip6)); 440 if (!m) { 441 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 442 return ENOBUFS; 443 } 444 } 445 ip6 = mtod(m, struct ip6_hdr *); 446 tos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; 447 448 /* 449 * Pickup the right outer dst addr from the list of candidates. 450 * ip6_dst has priority as it may be able to give us shorter IPv4 hops. 451 */ 452 ptr = NULL; 453 if (IN6_IS_ADDR_6TO4(&ip6->ip6_dst)) 454 ptr = GET_V4(&ip6->ip6_dst); 455 else if (IN6_IS_ADDR_6TO4(&dst6->sin6_addr)) 456 ptr = GET_V4(&dst6->sin6_addr); 457 else { 458 m_freem(m); 459 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 460 return ENETUNREACH; 461 } 462 bcopy(ptr, &in4, sizeof(in4)); 463 464 if (bpf_peers_present(ifp->if_bpf)) { 465 /* 466 * We need to prepend the address family as 467 * a four byte field. Cons up a dummy header 468 * to pacify bpf. This is safe because bpf 469 * will only read from the mbuf (i.e., it won't 470 * try to free it or keep a pointer a to it). 471 */ 472 u_int af = AF_INET6; 473 bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m); 474 } 475 476 M_PREPEND(m, sizeof(struct ip), M_NOWAIT); 477 if (m == NULL) { 478 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 479 return ENOBUFS; 480 } 481 ip = mtod(m, struct ip *); 482 483 bzero(ip, sizeof(*ip)); 484 485 bcopy(GET_V4(&addr6), &ip->ip_src, sizeof(ip->ip_src)); 486 bcopy(&in4, &ip->ip_dst, sizeof(ip->ip_dst)); 487 ip->ip_p = IPPROTO_IPV6; 488 ip->ip_ttl = ip_stf_ttl; 489 ip->ip_len = htons(m->m_pkthdr.len); 490 if (ifp->if_flags & IFF_LINK1) 491 ip_ecn_ingress(ECN_ALLOWED, &ip->ip_tos, &tos); 492 else 493 ip_ecn_ingress(ECN_NOCARE, &ip->ip_tos, &tos); 494 495 M_SETFIB(m, sc->sc_fibnum); 496 if_inc_counter(ifp, IFCOUNTER_OPACKETS, 1); 497 error = ip_output(m, NULL, NULL, 0, NULL, NULL); 498 499 return error; 500 } 501 502 static int 503 isrfc1918addr(struct in_addr *in) 504 { 505 /* 506 * returns 1 if private address range: 507 * 10.0.0.0/8 172.16.0.0/12 192.168.0.0/16 508 */ 509 if (stf_permit_rfc1918 == 0 && ( 510 (ntohl(in->s_addr) & 0xff000000) >> 24 == 10 || 511 (ntohl(in->s_addr) & 0xfff00000) >> 16 == 172 * 256 + 16 || 512 (ntohl(in->s_addr) & 0xffff0000) >> 16 == 192 * 256 + 168)) 513 return 1; 514 515 return 0; 516 } 517 518 static int 519 stf_checkaddr4(struct stf_softc *sc, struct in_addr *in, struct ifnet *inifp) 520 { 521 struct rm_priotracker in_ifa_tracker; 522 struct in_ifaddr *ia4; 523 524 /* 525 * reject packets with the following address: 526 * 224.0.0.0/4 0.0.0.0/8 127.0.0.0/8 255.0.0.0/8 527 */ 528 if (IN_MULTICAST(ntohl(in->s_addr))) 529 return -1; 530 switch ((ntohl(in->s_addr) & 0xff000000) >> 24) { 531 case 0: case 127: case 255: 532 return -1; 533 } 534 535 /* 536 * reject packets with private address range. 537 * (requirement from RFC3056 section 2 1st paragraph) 538 */ 539 if (isrfc1918addr(in)) 540 return -1; 541 542 /* 543 * reject packets with broadcast 544 */ 545 IN_IFADDR_RLOCK(&in_ifa_tracker); 546 TAILQ_FOREACH(ia4, &V_in_ifaddrhead, ia_link) { 547 if ((ia4->ia_ifa.ifa_ifp->if_flags & IFF_BROADCAST) == 0) 548 continue; 549 if (in->s_addr == ia4->ia_broadaddr.sin_addr.s_addr) { 550 IN_IFADDR_RUNLOCK(&in_ifa_tracker); 551 return -1; 552 } 553 } 554 IN_IFADDR_RUNLOCK(&in_ifa_tracker); 555 556 /* 557 * perform ingress filter 558 */ 559 if (sc && (STF2IFP(sc)->if_flags & IFF_LINK2) == 0 && inifp) { 560 struct sockaddr_in sin; 561 struct rtentry *rt; 562 563 bzero(&sin, sizeof(sin)); 564 sin.sin_family = AF_INET; 565 sin.sin_len = sizeof(struct sockaddr_in); 566 sin.sin_addr = *in; 567 rt = rtalloc1_fib((struct sockaddr *)&sin, 0, 568 0UL, sc->sc_fibnum); 569 if (!rt || rt->rt_ifp != inifp) { 570 #if 0 571 log(LOG_WARNING, "%s: packet from 0x%x dropped " 572 "due to ingress filter\n", if_name(STF2IFP(sc)), 573 (u_int32_t)ntohl(sin.sin_addr.s_addr)); 574 #endif 575 if (rt) 576 RTFREE_LOCKED(rt); 577 return -1; 578 } 579 RTFREE_LOCKED(rt); 580 } 581 582 return 0; 583 } 584 585 static int 586 stf_checkaddr6(struct stf_softc *sc, struct in6_addr *in6, struct ifnet *inifp) 587 { 588 /* 589 * check 6to4 addresses 590 */ 591 if (IN6_IS_ADDR_6TO4(in6)) { 592 struct in_addr in4; 593 bcopy(GET_V4(in6), &in4, sizeof(in4)); 594 return stf_checkaddr4(sc, &in4, inifp); 595 } 596 597 /* 598 * reject anything that look suspicious. the test is implemented 599 * in ip6_input too, but we check here as well to 600 * (1) reject bad packets earlier, and 601 * (2) to be safe against future ip6_input change. 602 */ 603 if (IN6_IS_ADDR_V4COMPAT(in6) || IN6_IS_ADDR_V4MAPPED(in6)) 604 return -1; 605 606 return 0; 607 } 608 609 static int 610 in_stf_input(struct mbuf **mp, int *offp, int proto) 611 { 612 struct stf_softc *sc; 613 struct ip *ip; 614 struct ip6_hdr *ip6; 615 struct mbuf *m; 616 u_int8_t otos, itos; 617 struct ifnet *ifp; 618 int off; 619 620 m = *mp; 621 off = *offp; 622 623 if (proto != IPPROTO_IPV6) { 624 m_freem(m); 625 return (IPPROTO_DONE); 626 } 627 628 ip = mtod(m, struct ip *); 629 630 sc = (struct stf_softc *)encap_getarg(m); 631 632 if (sc == NULL || (STF2IFP(sc)->if_flags & IFF_UP) == 0) { 633 m_freem(m); 634 return (IPPROTO_DONE); 635 } 636 637 ifp = STF2IFP(sc); 638 639 #ifdef MAC 640 mac_ifnet_create_mbuf(ifp, m); 641 #endif 642 643 /* 644 * perform sanity check against outer src/dst. 645 * for source, perform ingress filter as well. 646 */ 647 if (stf_checkaddr4(sc, &ip->ip_dst, NULL) < 0 || 648 stf_checkaddr4(sc, &ip->ip_src, m->m_pkthdr.rcvif) < 0) { 649 m_freem(m); 650 return (IPPROTO_DONE); 651 } 652 653 otos = ip->ip_tos; 654 m_adj(m, off); 655 656 if (m->m_len < sizeof(*ip6)) { 657 m = m_pullup(m, sizeof(*ip6)); 658 if (!m) 659 return (IPPROTO_DONE); 660 } 661 ip6 = mtod(m, struct ip6_hdr *); 662 663 /* 664 * perform sanity check against inner src/dst. 665 * for source, perform ingress filter as well. 666 */ 667 if (stf_checkaddr6(sc, &ip6->ip6_dst, NULL) < 0 || 668 stf_checkaddr6(sc, &ip6->ip6_src, m->m_pkthdr.rcvif) < 0) { 669 m_freem(m); 670 return (IPPROTO_DONE); 671 } 672 673 itos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; 674 if ((ifp->if_flags & IFF_LINK1) != 0) 675 ip_ecn_egress(ECN_ALLOWED, &otos, &itos); 676 else 677 ip_ecn_egress(ECN_NOCARE, &otos, &itos); 678 ip6->ip6_flow &= ~htonl(0xff << 20); 679 ip6->ip6_flow |= htonl((u_int32_t)itos << 20); 680 681 m->m_pkthdr.rcvif = ifp; 682 683 if (bpf_peers_present(ifp->if_bpf)) { 684 /* 685 * We need to prepend the address family as 686 * a four byte field. Cons up a dummy header 687 * to pacify bpf. This is safe because bpf 688 * will only read from the mbuf (i.e., it won't 689 * try to free it or keep a pointer a to it). 690 */ 691 u_int32_t af = AF_INET6; 692 bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m); 693 } 694 695 /* 696 * Put the packet to the network layer input queue according to the 697 * specified address family. 698 * See net/if_gif.c for possible issues with packet processing 699 * reorder due to extra queueing. 700 */ 701 if_inc_counter(ifp, IFCOUNTER_IPACKETS, 1); 702 if_inc_counter(ifp, IFCOUNTER_IBYTES, m->m_pkthdr.len); 703 M_SETFIB(m, ifp->if_fib); 704 netisr_dispatch(NETISR_IPV6, m); 705 return (IPPROTO_DONE); 706 } 707 708 static int 709 stf_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data) 710 { 711 struct ifaddr *ifa; 712 struct ifreq *ifr; 713 struct sockaddr_in6 *sin6; 714 struct in_addr addr; 715 int error, mtu; 716 717 error = 0; 718 switch (cmd) { 719 case SIOCSIFADDR: 720 ifa = (struct ifaddr *)data; 721 if (ifa == NULL || ifa->ifa_addr->sa_family != AF_INET6) { 722 error = EAFNOSUPPORT; 723 break; 724 } 725 sin6 = (struct sockaddr_in6 *)ifa->ifa_addr; 726 if (!IN6_IS_ADDR_6TO4(&sin6->sin6_addr)) { 727 error = EINVAL; 728 break; 729 } 730 bcopy(GET_V4(&sin6->sin6_addr), &addr, sizeof(addr)); 731 if (isrfc1918addr(&addr)) { 732 error = EINVAL; 733 break; 734 } 735 736 ifp->if_flags |= IFF_UP; 737 break; 738 739 case SIOCADDMULTI: 740 case SIOCDELMULTI: 741 ifr = (struct ifreq *)data; 742 if (ifr && ifr->ifr_addr.sa_family == AF_INET6) 743 ; 744 else 745 error = EAFNOSUPPORT; 746 break; 747 748 case SIOCGIFMTU: 749 break; 750 751 case SIOCSIFMTU: 752 ifr = (struct ifreq *)data; 753 mtu = ifr->ifr_mtu; 754 /* RFC 4213 3.2 ideal world MTU */ 755 if (mtu < IPV6_MINMTU || mtu > IF_MAXMTU - 20) 756 return (EINVAL); 757 ifp->if_mtu = mtu; 758 break; 759 760 default: 761 error = EINVAL; 762 break; 763 } 764 765 return error; 766 } 767