1 /* $FreeBSD$ */ 2 /* $KAME: if_stf.c,v 1.73 2001/12/03 11:08:30 keiichi Exp $ */ 3 4 /*- 5 * SPDX-License-Identifier: BSD-3-Clause 6 * 7 * Copyright (C) 2000 WIDE Project. 8 * All rights reserved. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. Neither the name of the project nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 35 /* 36 * 6to4 interface, based on RFC3056. 37 * 38 * 6to4 interface is NOT capable of link-layer (I mean, IPv4) multicasting. 39 * There is no address mapping defined from IPv6 multicast address to IPv4 40 * address. Therefore, we do not have IFF_MULTICAST on the interface. 41 * 42 * Due to the lack of address mapping for link-local addresses, we cannot 43 * throw packets toward link-local addresses (fe80::x). Also, we cannot throw 44 * packets to link-local multicast addresses (ff02::x). 45 * 46 * Here are interesting symptoms due to the lack of link-local address: 47 * 48 * Unicast routing exchange: 49 * - RIPng: Impossible. Uses link-local multicast packet toward ff02::9, 50 * and link-local addresses as nexthop. 51 * - OSPFv6: Impossible. OSPFv6 assumes that there's link-local address 52 * assigned to the link, and makes use of them. Also, HELLO packets use 53 * link-local multicast addresses (ff02::5 and ff02::6). 54 * - BGP4+: Maybe. You can only use global address as nexthop, and global 55 * address as TCP endpoint address. 56 * 57 * Multicast routing protocols: 58 * - PIM: Hello packet cannot be used to discover adjacent PIM routers. 59 * Adjacent PIM routers must be configured manually (is it really spec-wise 60 * correct thing to do?). 61 * 62 * ICMPv6: 63 * - Redirects cannot be used due to the lack of link-local address. 64 * 65 * stf interface does not have, and will not need, a link-local address. 66 * It seems to have no real benefit and does not help the above symptoms much. 67 * Even if we assign link-locals to interface, we cannot really 68 * use link-local unicast/multicast on top of 6to4 cloud (since there's no 69 * encapsulation defined for link-local address), and the above analysis does 70 * not change. RFC3056 does not mandate the assignment of link-local address 71 * either. 72 * 73 * 6to4 interface has security issues. Refer to 74 * http://playground.iijlab.net/i-d/draft-itojun-ipv6-transition-abuse-00.txt 75 * for details. The code tries to filter out some of malicious packets. 76 * Note that there is no way to be 100% secure. 77 */ 78 79 #include <sys/param.h> 80 #include <sys/systm.h> 81 #include <sys/socket.h> 82 #include <sys/sockio.h> 83 #include <sys/mbuf.h> 84 #include <sys/errno.h> 85 #include <sys/kernel.h> 86 #include <sys/lock.h> 87 #include <sys/module.h> 88 #include <sys/protosw.h> 89 #include <sys/proc.h> 90 #include <sys/queue.h> 91 #include <sys/rmlock.h> 92 #include <sys/sysctl.h> 93 #include <machine/cpu.h> 94 95 #include <sys/malloc.h> 96 97 #include <net/if.h> 98 #include <net/if_var.h> 99 #include <net/if_clone.h> 100 #include <net/route.h> 101 #include <net/netisr.h> 102 #include <net/if_types.h> 103 #include <net/vnet.h> 104 105 #include <netinet/in.h> 106 #include <netinet/in_fib.h> 107 #include <netinet/in_systm.h> 108 #include <netinet/ip.h> 109 #include <netinet/ip_var.h> 110 #include <netinet/in_var.h> 111 112 #include <netinet/ip6.h> 113 #include <netinet6/ip6_var.h> 114 #include <netinet6/in6_var.h> 115 #include <netinet/ip_ecn.h> 116 117 #include <netinet/ip_encap.h> 118 119 #include <machine/stdarg.h> 120 121 #include <net/bpf.h> 122 123 #include <security/mac/mac_framework.h> 124 125 SYSCTL_DECL(_net_link); 126 static SYSCTL_NODE(_net_link, IFT_STF, stf, CTLFLAG_RW, 0, "6to4 Interface"); 127 128 static int stf_permit_rfc1918 = 0; 129 SYSCTL_INT(_net_link_stf, OID_AUTO, permit_rfc1918, CTLFLAG_RWTUN, 130 &stf_permit_rfc1918, 0, "Permit the use of private IPv4 addresses"); 131 132 #define STFUNIT 0 133 134 #define IN6_IS_ADDR_6TO4(x) (ntohs((x)->s6_addr16[0]) == 0x2002) 135 136 /* 137 * XXX: Return a pointer with 16-bit aligned. Don't cast it to 138 * struct in_addr *; use bcopy() instead. 139 */ 140 #define GET_V4(x) (&(x)->s6_addr16[1]) 141 142 struct stf_softc { 143 struct ifnet *sc_ifp; 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 static MALLOC_DEFINE(M_STF, stfname, "6to4 Tunnel Interface"); 152 static const int ip_stf_ttl = 40; 153 154 extern struct domain inetdomain; 155 static int in_stf_input(struct mbuf **, int *, int); 156 static struct protosw in_stf_protosw = { 157 .pr_type = SOCK_RAW, 158 .pr_domain = &inetdomain, 159 .pr_protocol = IPPROTO_IPV6, 160 .pr_flags = PR_ATOMIC|PR_ADDR, 161 .pr_input = in_stf_input, 162 .pr_output = rip_output, 163 .pr_ctloutput = rip_ctloutput, 164 .pr_usrreqs = &rip_usrreqs 165 }; 166 167 static char *stfnames[] = {"stf0", "stf", "6to4", NULL}; 168 169 static int stfmodevent(module_t, int, void *); 170 static int stf_encapcheck(const struct mbuf *, int, int, void *); 171 static int stf_getsrcifa6(struct ifnet *, struct in6_addr *, struct in6_addr *); 172 static int stf_output(struct ifnet *, struct mbuf *, const struct sockaddr *, 173 struct route *); 174 static int isrfc1918addr(struct in_addr *); 175 static int stf_checkaddr4(struct stf_softc *, struct in_addr *, 176 struct ifnet *); 177 static int stf_checkaddr6(struct stf_softc *, struct in6_addr *, 178 struct ifnet *); 179 static int stf_ioctl(struct ifnet *, u_long, caddr_t); 180 181 static int stf_clone_match(struct if_clone *, const char *); 182 static int stf_clone_create(struct if_clone *, char *, size_t, caddr_t); 183 static int stf_clone_destroy(struct if_clone *, struct ifnet *); 184 static struct if_clone *stf_cloner; 185 186 static int 187 stf_clone_match(struct if_clone *ifc, const char *name) 188 { 189 int i; 190 191 for(i = 0; stfnames[i] != NULL; i++) { 192 if (strcmp(stfnames[i], name) == 0) 193 return (1); 194 } 195 196 return (0); 197 } 198 199 static int 200 stf_clone_create(struct if_clone *ifc, char *name, size_t len, caddr_t params) 201 { 202 char *dp; 203 int err, unit, wildcard; 204 struct stf_softc *sc; 205 struct ifnet *ifp; 206 207 err = ifc_name2unit(name, &unit); 208 if (err != 0) 209 return (err); 210 wildcard = (unit < 0); 211 212 /* 213 * We can only have one unit, but since unit allocation is 214 * already locked, we use it to keep from allocating extra 215 * interfaces. 216 */ 217 unit = STFUNIT; 218 err = ifc_alloc_unit(ifc, &unit); 219 if (err != 0) 220 return (err); 221 222 sc = malloc(sizeof(struct stf_softc), M_STF, M_WAITOK | M_ZERO); 223 ifp = STF2IFP(sc) = if_alloc(IFT_STF); 224 if (ifp == NULL) { 225 free(sc, M_STF); 226 ifc_free_unit(ifc, unit); 227 return (ENOSPC); 228 } 229 ifp->if_softc = sc; 230 sc->sc_fibnum = curthread->td_proc->p_fibnum; 231 232 /* 233 * Set the name manually rather then using if_initname because 234 * we don't conform to the default naming convention for interfaces. 235 * In the wildcard case, we need to update the name. 236 */ 237 if (wildcard) { 238 for (dp = name; *dp != '\0'; dp++); 239 if (snprintf(dp, len - (dp-name), "%d", unit) > 240 len - (dp-name) - 1) { 241 /* 242 * This can only be a programmer error and 243 * there's no straightforward way to recover if 244 * it happens. 245 */ 246 panic("if_clone_create(): interface name too long"); 247 } 248 } 249 strlcpy(ifp->if_xname, name, IFNAMSIZ); 250 ifp->if_dname = stfname; 251 ifp->if_dunit = IF_DUNIT_NONE; 252 253 sc->encap_cookie = encap_attach_func(AF_INET, IPPROTO_IPV6, 254 stf_encapcheck, &in_stf_protosw, sc); 255 if (sc->encap_cookie == NULL) { 256 if_printf(ifp, "attach failed\n"); 257 free(sc, M_STF); 258 ifc_free_unit(ifc, unit); 259 return (ENOMEM); 260 } 261 262 ifp->if_mtu = IPV6_MMTU; 263 ifp->if_ioctl = stf_ioctl; 264 ifp->if_output = stf_output; 265 ifp->if_snd.ifq_maxlen = ifqmaxlen; 266 if_attach(ifp); 267 bpfattach(ifp, DLT_NULL, sizeof(u_int32_t)); 268 return (0); 269 } 270 271 static int 272 stf_clone_destroy(struct if_clone *ifc, struct ifnet *ifp) 273 { 274 struct stf_softc *sc = ifp->if_softc; 275 int err; 276 277 err = encap_detach(sc->encap_cookie); 278 KASSERT(err == 0, ("Unexpected error detaching encap_cookie")); 279 bpfdetach(ifp); 280 if_detach(ifp); 281 if_free(ifp); 282 283 free(sc, M_STF); 284 ifc_free_unit(ifc, STFUNIT); 285 286 return (0); 287 } 288 289 static int 290 stfmodevent(module_t mod, int type, void *data) 291 { 292 293 switch (type) { 294 case MOD_LOAD: 295 stf_cloner = if_clone_advanced(stfname, 0, stf_clone_match, 296 stf_clone_create, stf_clone_destroy); 297 break; 298 case MOD_UNLOAD: 299 if_clone_detach(stf_cloner); 300 break; 301 default: 302 return (EOPNOTSUPP); 303 } 304 305 return (0); 306 } 307 308 static moduledata_t stf_mod = { 309 "if_stf", 310 stfmodevent, 311 0 312 }; 313 314 DECLARE_MODULE(if_stf, stf_mod, SI_SUB_PSEUDO, SI_ORDER_ANY); 315 316 static int 317 stf_encapcheck(const struct mbuf *m, int off, int proto, void *arg) 318 { 319 struct ip ip; 320 struct stf_softc *sc; 321 struct in_addr a, b, mask; 322 struct in6_addr addr6, mask6; 323 324 sc = (struct stf_softc *)arg; 325 if (sc == NULL) 326 return 0; 327 328 if ((STF2IFP(sc)->if_flags & IFF_UP) == 0) 329 return 0; 330 331 /* IFF_LINK0 means "no decapsulation" */ 332 if ((STF2IFP(sc)->if_flags & IFF_LINK0) != 0) 333 return 0; 334 335 if (proto != IPPROTO_IPV6) 336 return 0; 337 338 m_copydata(m, 0, sizeof(ip), (caddr_t)&ip); 339 340 if (ip.ip_v != 4) 341 return 0; 342 343 if (stf_getsrcifa6(STF2IFP(sc), &addr6, &mask6) != 0) 344 return (0); 345 346 /* 347 * check if IPv4 dst matches the IPv4 address derived from the 348 * local 6to4 address. 349 * success on: dst = 10.1.1.1, ia6->ia_addr = 2002:0a01:0101:... 350 */ 351 if (bcmp(GET_V4(&addr6), &ip.ip_dst, sizeof(ip.ip_dst)) != 0) 352 return 0; 353 354 /* 355 * check if IPv4 src matches the IPv4 address derived from the 356 * local 6to4 address masked by prefixmask. 357 * success on: src = 10.1.1.1, ia6->ia_addr = 2002:0a00:.../24 358 * fail on: src = 10.1.1.1, ia6->ia_addr = 2002:0b00:.../24 359 */ 360 bzero(&a, sizeof(a)); 361 bcopy(GET_V4(&addr6), &a, sizeof(a)); 362 bcopy(GET_V4(&mask6), &mask, sizeof(mask)); 363 a.s_addr &= mask.s_addr; 364 b = ip.ip_src; 365 b.s_addr &= mask.s_addr; 366 if (a.s_addr != b.s_addr) 367 return 0; 368 369 /* stf interface makes single side match only */ 370 return 32; 371 } 372 373 static int 374 stf_getsrcifa6(struct ifnet *ifp, struct in6_addr *addr, struct in6_addr *mask) 375 { 376 struct ifaddr *ia; 377 struct in_ifaddr *ia4; 378 struct in6_ifaddr *ia6; 379 struct sockaddr_in6 *sin6; 380 struct in_addr in; 381 382 if_addr_rlock(ifp); 383 TAILQ_FOREACH(ia, &ifp->if_addrhead, ifa_link) { 384 if (ia->ifa_addr->sa_family != AF_INET6) 385 continue; 386 sin6 = (struct sockaddr_in6 *)ia->ifa_addr; 387 if (!IN6_IS_ADDR_6TO4(&sin6->sin6_addr)) 388 continue; 389 390 bcopy(GET_V4(&sin6->sin6_addr), &in, sizeof(in)); 391 LIST_FOREACH(ia4, INADDR_HASH(in.s_addr), ia_hash) 392 if (ia4->ia_addr.sin_addr.s_addr == in.s_addr) 393 break; 394 if (ia4 == NULL) 395 continue; 396 397 ia6 = (struct in6_ifaddr *)ia; 398 399 *addr = sin6->sin6_addr; 400 *mask = ia6->ia_prefixmask.sin6_addr; 401 if_addr_runlock(ifp); 402 return (0); 403 } 404 if_addr_runlock(ifp); 405 406 return (ENOENT); 407 } 408 409 static int 410 stf_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst, 411 struct route *ro) 412 { 413 struct stf_softc *sc; 414 const struct sockaddr_in6 *dst6; 415 struct in_addr in4; 416 const void *ptr; 417 u_int8_t tos; 418 struct ip *ip; 419 struct ip6_hdr *ip6; 420 struct in6_addr addr6, mask6; 421 int error; 422 423 #ifdef MAC 424 error = mac_ifnet_check_transmit(ifp, m); 425 if (error) { 426 m_freem(m); 427 return (error); 428 } 429 #endif 430 431 sc = ifp->if_softc; 432 dst6 = (const struct sockaddr_in6 *)dst; 433 434 /* just in case */ 435 if ((ifp->if_flags & IFF_UP) == 0) { 436 m_freem(m); 437 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 438 return ENETDOWN; 439 } 440 441 /* 442 * If we don't have an ip4 address that match my inner ip6 address, 443 * we shouldn't generate output. Without this check, we'll end up 444 * using wrong IPv4 source. 445 */ 446 if (stf_getsrcifa6(ifp, &addr6, &mask6) != 0) { 447 m_freem(m); 448 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 449 return ENETDOWN; 450 } 451 452 if (m->m_len < sizeof(*ip6)) { 453 m = m_pullup(m, sizeof(*ip6)); 454 if (!m) { 455 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 456 return ENOBUFS; 457 } 458 } 459 ip6 = mtod(m, struct ip6_hdr *); 460 tos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; 461 462 /* 463 * Pickup the right outer dst addr from the list of candidates. 464 * ip6_dst has priority as it may be able to give us shorter IPv4 hops. 465 */ 466 ptr = NULL; 467 if (IN6_IS_ADDR_6TO4(&ip6->ip6_dst)) 468 ptr = GET_V4(&ip6->ip6_dst); 469 else if (IN6_IS_ADDR_6TO4(&dst6->sin6_addr)) 470 ptr = GET_V4(&dst6->sin6_addr); 471 else { 472 m_freem(m); 473 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 474 return ENETUNREACH; 475 } 476 bcopy(ptr, &in4, sizeof(in4)); 477 478 if (bpf_peers_present(ifp->if_bpf)) { 479 /* 480 * We need to prepend the address family as 481 * a four byte field. Cons up a dummy header 482 * to pacify bpf. This is safe because bpf 483 * will only read from the mbuf (i.e., it won't 484 * try to free it or keep a pointer a to it). 485 */ 486 u_int af = AF_INET6; 487 bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m); 488 } 489 490 M_PREPEND(m, sizeof(struct ip), M_NOWAIT); 491 if (m == NULL) { 492 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 493 return ENOBUFS; 494 } 495 ip = mtod(m, struct ip *); 496 497 bzero(ip, sizeof(*ip)); 498 499 bcopy(GET_V4(&addr6), &ip->ip_src, sizeof(ip->ip_src)); 500 bcopy(&in4, &ip->ip_dst, sizeof(ip->ip_dst)); 501 ip->ip_p = IPPROTO_IPV6; 502 ip->ip_ttl = ip_stf_ttl; 503 ip->ip_len = htons(m->m_pkthdr.len); 504 if (ifp->if_flags & IFF_LINK1) 505 ip_ecn_ingress(ECN_ALLOWED, &ip->ip_tos, &tos); 506 else 507 ip_ecn_ingress(ECN_NOCARE, &ip->ip_tos, &tos); 508 509 M_SETFIB(m, sc->sc_fibnum); 510 if_inc_counter(ifp, IFCOUNTER_OPACKETS, 1); 511 error = ip_output(m, NULL, NULL, 0, NULL, NULL); 512 513 return error; 514 } 515 516 static int 517 isrfc1918addr(struct in_addr *in) 518 { 519 /* 520 * returns 1 if private address range: 521 * 10.0.0.0/8 172.16.0.0/12 192.168.0.0/16 522 */ 523 if (stf_permit_rfc1918 == 0 && ( 524 (ntohl(in->s_addr) & 0xff000000) >> 24 == 10 || 525 (ntohl(in->s_addr) & 0xfff00000) >> 16 == 172 * 256 + 16 || 526 (ntohl(in->s_addr) & 0xffff0000) >> 16 == 192 * 256 + 168)) 527 return 1; 528 529 return 0; 530 } 531 532 static int 533 stf_checkaddr4(struct stf_softc *sc, struct in_addr *in, struct ifnet *inifp) 534 { 535 struct rm_priotracker in_ifa_tracker; 536 struct in_ifaddr *ia4; 537 538 /* 539 * reject packets with the following address: 540 * 224.0.0.0/4 0.0.0.0/8 127.0.0.0/8 255.0.0.0/8 541 */ 542 if (IN_MULTICAST(ntohl(in->s_addr))) 543 return -1; 544 switch ((ntohl(in->s_addr) & 0xff000000) >> 24) { 545 case 0: case 127: case 255: 546 return -1; 547 } 548 549 /* 550 * reject packets with private address range. 551 * (requirement from RFC3056 section 2 1st paragraph) 552 */ 553 if (isrfc1918addr(in)) 554 return -1; 555 556 /* 557 * reject packets with broadcast 558 */ 559 IN_IFADDR_RLOCK(&in_ifa_tracker); 560 TAILQ_FOREACH(ia4, &V_in_ifaddrhead, ia_link) { 561 if ((ia4->ia_ifa.ifa_ifp->if_flags & IFF_BROADCAST) == 0) 562 continue; 563 if (in->s_addr == ia4->ia_broadaddr.sin_addr.s_addr) { 564 IN_IFADDR_RUNLOCK(&in_ifa_tracker); 565 return -1; 566 } 567 } 568 IN_IFADDR_RUNLOCK(&in_ifa_tracker); 569 570 /* 571 * perform ingress filter 572 */ 573 if (sc && (STF2IFP(sc)->if_flags & IFF_LINK2) == 0 && inifp) { 574 struct nhop4_basic nh4; 575 576 if (fib4_lookup_nh_basic(sc->sc_fibnum, *in, 0, 0, &nh4) != 0) 577 return (-1); 578 579 if (nh4.nh_ifp != inifp) 580 return (-1); 581 } 582 583 return 0; 584 } 585 586 static int 587 stf_checkaddr6(struct stf_softc *sc, struct in6_addr *in6, struct ifnet *inifp) 588 { 589 /* 590 * check 6to4 addresses 591 */ 592 if (IN6_IS_ADDR_6TO4(in6)) { 593 struct in_addr in4; 594 bcopy(GET_V4(in6), &in4, sizeof(in4)); 595 return stf_checkaddr4(sc, &in4, inifp); 596 } 597 598 /* 599 * reject anything that look suspicious. the test is implemented 600 * in ip6_input too, but we check here as well to 601 * (1) reject bad packets earlier, and 602 * (2) to be safe against future ip6_input change. 603 */ 604 if (IN6_IS_ADDR_V4COMPAT(in6) || IN6_IS_ADDR_V4MAPPED(in6)) 605 return -1; 606 607 return 0; 608 } 609 610 static int 611 in_stf_input(struct mbuf **mp, int *offp, int proto) 612 { 613 struct stf_softc *sc; 614 struct ip *ip; 615 struct ip6_hdr *ip6; 616 struct mbuf *m; 617 u_int8_t otos, itos; 618 struct ifnet *ifp; 619 int off; 620 621 m = *mp; 622 off = *offp; 623 624 if (proto != IPPROTO_IPV6) { 625 m_freem(m); 626 return (IPPROTO_DONE); 627 } 628 629 ip = mtod(m, struct ip *); 630 631 sc = (struct stf_softc *)encap_getarg(m); 632 633 if (sc == NULL || (STF2IFP(sc)->if_flags & IFF_UP) == 0) { 634 m_freem(m); 635 return (IPPROTO_DONE); 636 } 637 638 ifp = STF2IFP(sc); 639 640 #ifdef MAC 641 mac_ifnet_create_mbuf(ifp, m); 642 #endif 643 644 /* 645 * perform sanity check against outer src/dst. 646 * for source, perform ingress filter as well. 647 */ 648 if (stf_checkaddr4(sc, &ip->ip_dst, NULL) < 0 || 649 stf_checkaddr4(sc, &ip->ip_src, m->m_pkthdr.rcvif) < 0) { 650 m_freem(m); 651 return (IPPROTO_DONE); 652 } 653 654 otos = ip->ip_tos; 655 m_adj(m, off); 656 657 if (m->m_len < sizeof(*ip6)) { 658 m = m_pullup(m, sizeof(*ip6)); 659 if (!m) 660 return (IPPROTO_DONE); 661 } 662 ip6 = mtod(m, struct ip6_hdr *); 663 664 /* 665 * perform sanity check against inner src/dst. 666 * for source, perform ingress filter as well. 667 */ 668 if (stf_checkaddr6(sc, &ip6->ip6_dst, NULL) < 0 || 669 stf_checkaddr6(sc, &ip6->ip6_src, m->m_pkthdr.rcvif) < 0) { 670 m_freem(m); 671 return (IPPROTO_DONE); 672 } 673 674 itos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; 675 if ((ifp->if_flags & IFF_LINK1) != 0) 676 ip_ecn_egress(ECN_ALLOWED, &otos, &itos); 677 else 678 ip_ecn_egress(ECN_NOCARE, &otos, &itos); 679 ip6->ip6_flow &= ~htonl(0xff << 20); 680 ip6->ip6_flow |= htonl((u_int32_t)itos << 20); 681 682 m->m_pkthdr.rcvif = ifp; 683 684 if (bpf_peers_present(ifp->if_bpf)) { 685 /* 686 * We need to prepend the address family as 687 * a four byte field. Cons up a dummy header 688 * to pacify bpf. This is safe because bpf 689 * will only read from the mbuf (i.e., it won't 690 * try to free it or keep a pointer a to it). 691 */ 692 u_int32_t af = AF_INET6; 693 bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m); 694 } 695 696 /* 697 * Put the packet to the network layer input queue according to the 698 * specified address family. 699 * See net/if_gif.c for possible issues with packet processing 700 * reorder due to extra queueing. 701 */ 702 if_inc_counter(ifp, IFCOUNTER_IPACKETS, 1); 703 if_inc_counter(ifp, IFCOUNTER_IBYTES, m->m_pkthdr.len); 704 M_SETFIB(m, ifp->if_fib); 705 netisr_dispatch(NETISR_IPV6, m); 706 return (IPPROTO_DONE); 707 } 708 709 static int 710 stf_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data) 711 { 712 struct ifaddr *ifa; 713 struct ifreq *ifr; 714 struct sockaddr_in6 *sin6; 715 struct in_addr addr; 716 int error, mtu; 717 718 error = 0; 719 switch (cmd) { 720 case SIOCSIFADDR: 721 ifa = (struct ifaddr *)data; 722 if (ifa == NULL || ifa->ifa_addr->sa_family != AF_INET6) { 723 error = EAFNOSUPPORT; 724 break; 725 } 726 sin6 = (struct sockaddr_in6 *)ifa->ifa_addr; 727 if (!IN6_IS_ADDR_6TO4(&sin6->sin6_addr)) { 728 error = EINVAL; 729 break; 730 } 731 bcopy(GET_V4(&sin6->sin6_addr), &addr, sizeof(addr)); 732 if (isrfc1918addr(&addr)) { 733 error = EINVAL; 734 break; 735 } 736 737 ifp->if_flags |= IFF_UP; 738 break; 739 740 case SIOCADDMULTI: 741 case SIOCDELMULTI: 742 ifr = (struct ifreq *)data; 743 if (ifr && ifr->ifr_addr.sa_family == AF_INET6) 744 ; 745 else 746 error = EAFNOSUPPORT; 747 break; 748 749 case SIOCGIFMTU: 750 break; 751 752 case SIOCSIFMTU: 753 ifr = (struct ifreq *)data; 754 mtu = ifr->ifr_mtu; 755 /* RFC 4213 3.2 ideal world MTU */ 756 if (mtu < IPV6_MINMTU || mtu > IF_MAXMTU - 20) 757 return (EINVAL); 758 ifp->if_mtu = mtu; 759 break; 760 761 default: 762 error = EINVAL; 763 break; 764 } 765 766 return error; 767 } 768