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 char *dp; 206 int err, unit, wildcard; 207 struct stf_softc *sc; 208 struct ifnet *ifp; 209 210 err = ifc_name2unit(name, &unit); 211 if (err != 0) 212 return (err); 213 wildcard = (unit < 0); 214 215 /* 216 * We can only have one unit, but since unit allocation is 217 * already locked, we use it to keep from allocating extra 218 * interfaces. 219 */ 220 unit = STFUNIT; 221 err = ifc_alloc_unit(ifc, &unit); 222 if (err != 0) 223 return (err); 224 225 sc = malloc(sizeof(struct stf_softc), M_STF, M_WAITOK | M_ZERO); 226 ifp = STF2IFP(sc) = if_alloc(IFT_STF); 227 if (ifp == NULL) { 228 free(sc, M_STF); 229 ifc_free_unit(ifc, unit); 230 return (ENOSPC); 231 } 232 ifp->if_softc = sc; 233 sc->sc_fibnum = curthread->td_proc->p_fibnum; 234 235 /* 236 * Set the name manually rather then using if_initname because 237 * we don't conform to the default naming convention for interfaces. 238 * In the wildcard case, we need to update the name. 239 */ 240 if (wildcard) { 241 for (dp = name; *dp != '\0'; dp++); 242 if (snprintf(dp, len - (dp-name), "%d", unit) > 243 len - (dp-name) - 1) { 244 /* 245 * This can only be a programmer error and 246 * there's no straightforward way to recover if 247 * it happens. 248 */ 249 panic("if_clone_create(): interface name too long"); 250 } 251 } 252 strlcpy(ifp->if_xname, name, IFNAMSIZ); 253 ifp->if_dname = stfname; 254 ifp->if_dunit = IF_DUNIT_NONE; 255 256 mtx_init(&(sc)->sc_ro_mtx, "stf ro", NULL, MTX_DEF); 257 sc->encap_cookie = encap_attach_func(AF_INET, IPPROTO_IPV6, 258 stf_encapcheck, &in_stf_protosw, sc); 259 if (sc->encap_cookie == NULL) { 260 if_printf(ifp, "attach failed\n"); 261 free(sc, M_STF); 262 ifc_free_unit(ifc, unit); 263 return (ENOMEM); 264 } 265 266 ifp->if_mtu = IPV6_MMTU; 267 ifp->if_ioctl = stf_ioctl; 268 ifp->if_output = stf_output; 269 ifp->if_snd.ifq_maxlen = ifqmaxlen; 270 if_attach(ifp); 271 bpfattach(ifp, DLT_NULL, sizeof(u_int32_t)); 272 return (0); 273 } 274 275 static int 276 stf_clone_destroy(struct if_clone *ifc, struct ifnet *ifp) 277 { 278 struct stf_softc *sc = ifp->if_softc; 279 int err; 280 281 err = encap_detach(sc->encap_cookie); 282 KASSERT(err == 0, ("Unexpected error detaching encap_cookie")); 283 mtx_destroy(&(sc)->sc_ro_mtx); 284 bpfdetach(ifp); 285 if_detach(ifp); 286 if_free(ifp); 287 288 free(sc, M_STF); 289 ifc_free_unit(ifc, STFUNIT); 290 291 return (0); 292 } 293 294 static int 295 stfmodevent(module_t mod, int type, void *data) 296 { 297 298 switch (type) { 299 case MOD_LOAD: 300 stf_cloner = if_clone_advanced(stfname, 0, stf_clone_match, 301 stf_clone_create, stf_clone_destroy); 302 break; 303 case MOD_UNLOAD: 304 if_clone_detach(stf_cloner); 305 break; 306 default: 307 return (EOPNOTSUPP); 308 } 309 310 return (0); 311 } 312 313 static moduledata_t stf_mod = { 314 "if_stf", 315 stfmodevent, 316 0 317 }; 318 319 DECLARE_MODULE(if_stf, stf_mod, SI_SUB_PSEUDO, SI_ORDER_ANY); 320 321 static int 322 stf_encapcheck(const struct mbuf *m, int off, int proto, void *arg) 323 { 324 struct ip ip; 325 struct stf_softc *sc; 326 struct in_addr a, b, mask; 327 struct in6_addr addr6, mask6; 328 329 sc = (struct stf_softc *)arg; 330 if (sc == NULL) 331 return 0; 332 333 if ((STF2IFP(sc)->if_flags & IFF_UP) == 0) 334 return 0; 335 336 /* IFF_LINK0 means "no decapsulation" */ 337 if ((STF2IFP(sc)->if_flags & IFF_LINK0) != 0) 338 return 0; 339 340 if (proto != IPPROTO_IPV6) 341 return 0; 342 343 m_copydata(m, 0, sizeof(ip), (caddr_t)&ip); 344 345 if (ip.ip_v != 4) 346 return 0; 347 348 if (stf_getsrcifa6(STF2IFP(sc), &addr6, &mask6) != 0) 349 return (0); 350 351 /* 352 * check if IPv4 dst matches the IPv4 address derived from the 353 * local 6to4 address. 354 * success on: dst = 10.1.1.1, ia6->ia_addr = 2002:0a01:0101:... 355 */ 356 if (bcmp(GET_V4(&addr6), &ip.ip_dst, sizeof(ip.ip_dst)) != 0) 357 return 0; 358 359 /* 360 * check if IPv4 src matches the IPv4 address derived from the 361 * local 6to4 address masked by prefixmask. 362 * success on: src = 10.1.1.1, ia6->ia_addr = 2002:0a00:.../24 363 * fail on: src = 10.1.1.1, ia6->ia_addr = 2002:0b00:.../24 364 */ 365 bzero(&a, sizeof(a)); 366 bcopy(GET_V4(&addr6), &a, sizeof(a)); 367 bcopy(GET_V4(&mask6), &mask, sizeof(mask)); 368 a.s_addr &= mask.s_addr; 369 b = ip.ip_src; 370 b.s_addr &= mask.s_addr; 371 if (a.s_addr != b.s_addr) 372 return 0; 373 374 /* stf interface makes single side match only */ 375 return 32; 376 } 377 378 static int 379 stf_getsrcifa6(struct ifnet *ifp, struct in6_addr *addr, struct in6_addr *mask) 380 { 381 struct ifaddr *ia; 382 struct in_ifaddr *ia4; 383 struct in6_ifaddr *ia6; 384 struct sockaddr_in6 *sin6; 385 struct in_addr in; 386 387 if_addr_rlock(ifp); 388 TAILQ_FOREACH(ia, &ifp->if_addrhead, ifa_link) { 389 if (ia->ifa_addr->sa_family != AF_INET6) 390 continue; 391 sin6 = (struct sockaddr_in6 *)ia->ifa_addr; 392 if (!IN6_IS_ADDR_6TO4(&sin6->sin6_addr)) 393 continue; 394 395 bcopy(GET_V4(&sin6->sin6_addr), &in, sizeof(in)); 396 LIST_FOREACH(ia4, INADDR_HASH(in.s_addr), ia_hash) 397 if (ia4->ia_addr.sin_addr.s_addr == in.s_addr) 398 break; 399 if (ia4 == NULL) 400 continue; 401 402 ia6 = (struct in6_ifaddr *)ia; 403 404 *addr = sin6->sin6_addr; 405 *mask = ia6->ia_prefixmask.sin6_addr; 406 if_addr_runlock(ifp); 407 return (0); 408 } 409 if_addr_runlock(ifp); 410 411 return (ENOENT); 412 } 413 414 static int 415 stf_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst, 416 struct route *ro) 417 { 418 struct stf_softc *sc; 419 const struct sockaddr_in6 *dst6; 420 struct in_addr in4; 421 const void *ptr; 422 u_int8_t tos; 423 struct ip *ip; 424 struct ip6_hdr *ip6; 425 struct in6_addr addr6, mask6; 426 int error; 427 428 #ifdef MAC 429 error = mac_ifnet_check_transmit(ifp, m); 430 if (error) { 431 m_freem(m); 432 return (error); 433 } 434 #endif 435 436 sc = ifp->if_softc; 437 dst6 = (const struct sockaddr_in6 *)dst; 438 439 /* just in case */ 440 if ((ifp->if_flags & IFF_UP) == 0) { 441 m_freem(m); 442 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 443 return ENETDOWN; 444 } 445 446 /* 447 * If we don't have an ip4 address that match my inner ip6 address, 448 * we shouldn't generate output. Without this check, we'll end up 449 * using wrong IPv4 source. 450 */ 451 if (stf_getsrcifa6(ifp, &addr6, &mask6) != 0) { 452 m_freem(m); 453 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 454 return ENETDOWN; 455 } 456 457 if (m->m_len < sizeof(*ip6)) { 458 m = m_pullup(m, sizeof(*ip6)); 459 if (!m) { 460 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 461 return ENOBUFS; 462 } 463 } 464 ip6 = mtod(m, struct ip6_hdr *); 465 tos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; 466 467 /* 468 * Pickup the right outer dst addr from the list of candidates. 469 * ip6_dst has priority as it may be able to give us shorter IPv4 hops. 470 */ 471 ptr = NULL; 472 if (IN6_IS_ADDR_6TO4(&ip6->ip6_dst)) 473 ptr = GET_V4(&ip6->ip6_dst); 474 else if (IN6_IS_ADDR_6TO4(&dst6->sin6_addr)) 475 ptr = GET_V4(&dst6->sin6_addr); 476 else { 477 m_freem(m); 478 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 479 return ENETUNREACH; 480 } 481 bcopy(ptr, &in4, sizeof(in4)); 482 483 if (bpf_peers_present(ifp->if_bpf)) { 484 /* 485 * We need to prepend the address family as 486 * a four byte field. Cons up a dummy header 487 * to pacify bpf. This is safe because bpf 488 * will only read from the mbuf (i.e., it won't 489 * try to free it or keep a pointer a to it). 490 */ 491 u_int af = AF_INET6; 492 bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m); 493 } 494 495 M_PREPEND(m, sizeof(struct ip), M_NOWAIT); 496 if (m == NULL) { 497 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 498 return ENOBUFS; 499 } 500 ip = mtod(m, struct ip *); 501 502 bzero(ip, sizeof(*ip)); 503 504 bcopy(GET_V4(&addr6), &ip->ip_src, sizeof(ip->ip_src)); 505 bcopy(&in4, &ip->ip_dst, sizeof(ip->ip_dst)); 506 ip->ip_p = IPPROTO_IPV6; 507 ip->ip_ttl = ip_stf_ttl; 508 ip->ip_len = htons(m->m_pkthdr.len); 509 if (ifp->if_flags & IFF_LINK1) 510 ip_ecn_ingress(ECN_ALLOWED, &ip->ip_tos, &tos); 511 else 512 ip_ecn_ingress(ECN_NOCARE, &ip->ip_tos, &tos); 513 514 M_SETFIB(m, sc->sc_fibnum); 515 if_inc_counter(ifp, IFCOUNTER_OPACKETS, 1); 516 error = ip_output(m, NULL, NULL, 0, NULL, NULL); 517 518 return error; 519 } 520 521 static int 522 isrfc1918addr(struct in_addr *in) 523 { 524 /* 525 * returns 1 if private address range: 526 * 10.0.0.0/8 172.16.0.0/12 192.168.0.0/16 527 */ 528 if (stf_permit_rfc1918 == 0 && ( 529 (ntohl(in->s_addr) & 0xff000000) >> 24 == 10 || 530 (ntohl(in->s_addr) & 0xfff00000) >> 16 == 172 * 256 + 16 || 531 (ntohl(in->s_addr) & 0xffff0000) >> 16 == 192 * 256 + 168)) 532 return 1; 533 534 return 0; 535 } 536 537 static int 538 stf_checkaddr4(struct stf_softc *sc, struct in_addr *in, struct ifnet *inifp) 539 { 540 struct rm_priotracker in_ifa_tracker; 541 struct in_ifaddr *ia4; 542 543 /* 544 * reject packets with the following address: 545 * 224.0.0.0/4 0.0.0.0/8 127.0.0.0/8 255.0.0.0/8 546 */ 547 if (IN_MULTICAST(ntohl(in->s_addr))) 548 return -1; 549 switch ((ntohl(in->s_addr) & 0xff000000) >> 24) { 550 case 0: case 127: case 255: 551 return -1; 552 } 553 554 /* 555 * reject packets with private address range. 556 * (requirement from RFC3056 section 2 1st paragraph) 557 */ 558 if (isrfc1918addr(in)) 559 return -1; 560 561 /* 562 * reject packets with broadcast 563 */ 564 IN_IFADDR_RLOCK(&in_ifa_tracker); 565 TAILQ_FOREACH(ia4, &V_in_ifaddrhead, ia_link) { 566 if ((ia4->ia_ifa.ifa_ifp->if_flags & IFF_BROADCAST) == 0) 567 continue; 568 if (in->s_addr == ia4->ia_broadaddr.sin_addr.s_addr) { 569 IN_IFADDR_RUNLOCK(&in_ifa_tracker); 570 return -1; 571 } 572 } 573 IN_IFADDR_RUNLOCK(&in_ifa_tracker); 574 575 /* 576 * perform ingress filter 577 */ 578 if (sc && (STF2IFP(sc)->if_flags & IFF_LINK2) == 0 && inifp) { 579 struct nhop4_basic nh4; 580 581 if (fib4_lookup_nh_basic(sc->sc_fibnum, *in, 0, 0, &nh4) != 0) 582 return (-1); 583 584 if (nh4.nh_ifp != inifp) 585 return (-1); 586 } 587 588 return 0; 589 } 590 591 static int 592 stf_checkaddr6(struct stf_softc *sc, struct in6_addr *in6, struct ifnet *inifp) 593 { 594 /* 595 * check 6to4 addresses 596 */ 597 if (IN6_IS_ADDR_6TO4(in6)) { 598 struct in_addr in4; 599 bcopy(GET_V4(in6), &in4, sizeof(in4)); 600 return stf_checkaddr4(sc, &in4, inifp); 601 } 602 603 /* 604 * reject anything that look suspicious. the test is implemented 605 * in ip6_input too, but we check here as well to 606 * (1) reject bad packets earlier, and 607 * (2) to be safe against future ip6_input change. 608 */ 609 if (IN6_IS_ADDR_V4COMPAT(in6) || IN6_IS_ADDR_V4MAPPED(in6)) 610 return -1; 611 612 return 0; 613 } 614 615 static int 616 in_stf_input(struct mbuf **mp, int *offp, int proto) 617 { 618 struct stf_softc *sc; 619 struct ip *ip; 620 struct ip6_hdr *ip6; 621 struct mbuf *m; 622 u_int8_t otos, itos; 623 struct ifnet *ifp; 624 int off; 625 626 m = *mp; 627 off = *offp; 628 629 if (proto != IPPROTO_IPV6) { 630 m_freem(m); 631 return (IPPROTO_DONE); 632 } 633 634 ip = mtod(m, struct ip *); 635 636 sc = (struct stf_softc *)encap_getarg(m); 637 638 if (sc == NULL || (STF2IFP(sc)->if_flags & IFF_UP) == 0) { 639 m_freem(m); 640 return (IPPROTO_DONE); 641 } 642 643 ifp = STF2IFP(sc); 644 645 #ifdef MAC 646 mac_ifnet_create_mbuf(ifp, m); 647 #endif 648 649 /* 650 * perform sanity check against outer src/dst. 651 * for source, perform ingress filter as well. 652 */ 653 if (stf_checkaddr4(sc, &ip->ip_dst, NULL) < 0 || 654 stf_checkaddr4(sc, &ip->ip_src, m->m_pkthdr.rcvif) < 0) { 655 m_freem(m); 656 return (IPPROTO_DONE); 657 } 658 659 otos = ip->ip_tos; 660 m_adj(m, off); 661 662 if (m->m_len < sizeof(*ip6)) { 663 m = m_pullup(m, sizeof(*ip6)); 664 if (!m) 665 return (IPPROTO_DONE); 666 } 667 ip6 = mtod(m, struct ip6_hdr *); 668 669 /* 670 * perform sanity check against inner src/dst. 671 * for source, perform ingress filter as well. 672 */ 673 if (stf_checkaddr6(sc, &ip6->ip6_dst, NULL) < 0 || 674 stf_checkaddr6(sc, &ip6->ip6_src, m->m_pkthdr.rcvif) < 0) { 675 m_freem(m); 676 return (IPPROTO_DONE); 677 } 678 679 itos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; 680 if ((ifp->if_flags & IFF_LINK1) != 0) 681 ip_ecn_egress(ECN_ALLOWED, &otos, &itos); 682 else 683 ip_ecn_egress(ECN_NOCARE, &otos, &itos); 684 ip6->ip6_flow &= ~htonl(0xff << 20); 685 ip6->ip6_flow |= htonl((u_int32_t)itos << 20); 686 687 m->m_pkthdr.rcvif = ifp; 688 689 if (bpf_peers_present(ifp->if_bpf)) { 690 /* 691 * We need to prepend the address family as 692 * a four byte field. Cons up a dummy header 693 * to pacify bpf. This is safe because bpf 694 * will only read from the mbuf (i.e., it won't 695 * try to free it or keep a pointer a to it). 696 */ 697 u_int32_t af = AF_INET6; 698 bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m); 699 } 700 701 /* 702 * Put the packet to the network layer input queue according to the 703 * specified address family. 704 * See net/if_gif.c for possible issues with packet processing 705 * reorder due to extra queueing. 706 */ 707 if_inc_counter(ifp, IFCOUNTER_IPACKETS, 1); 708 if_inc_counter(ifp, IFCOUNTER_IBYTES, m->m_pkthdr.len); 709 M_SETFIB(m, ifp->if_fib); 710 netisr_dispatch(NETISR_IPV6, m); 711 return (IPPROTO_DONE); 712 } 713 714 static int 715 stf_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data) 716 { 717 struct ifaddr *ifa; 718 struct ifreq *ifr; 719 struct sockaddr_in6 *sin6; 720 struct in_addr addr; 721 int error, mtu; 722 723 error = 0; 724 switch (cmd) { 725 case SIOCSIFADDR: 726 ifa = (struct ifaddr *)data; 727 if (ifa == NULL || ifa->ifa_addr->sa_family != AF_INET6) { 728 error = EAFNOSUPPORT; 729 break; 730 } 731 sin6 = (struct sockaddr_in6 *)ifa->ifa_addr; 732 if (!IN6_IS_ADDR_6TO4(&sin6->sin6_addr)) { 733 error = EINVAL; 734 break; 735 } 736 bcopy(GET_V4(&sin6->sin6_addr), &addr, sizeof(addr)); 737 if (isrfc1918addr(&addr)) { 738 error = EINVAL; 739 break; 740 } 741 742 ifp->if_flags |= IFF_UP; 743 break; 744 745 case SIOCADDMULTI: 746 case SIOCDELMULTI: 747 ifr = (struct ifreq *)data; 748 if (ifr && ifr->ifr_addr.sa_family == AF_INET6) 749 ; 750 else 751 error = EAFNOSUPPORT; 752 break; 753 754 case SIOCGIFMTU: 755 break; 756 757 case SIOCSIFMTU: 758 ifr = (struct ifreq *)data; 759 mtu = ifr->ifr_mtu; 760 /* RFC 4213 3.2 ideal world MTU */ 761 if (mtu < IPV6_MINMTU || mtu > IF_MAXMTU - 20) 762 return (EINVAL); 763 ifp->if_mtu = mtu; 764 break; 765 766 default: 767 error = EINVAL; 768 break; 769 } 770 771 return error; 772 } 773