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 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 static MALLOC_DEFINE(M_STF, stfname, "6to4 Tunnel Interface"); 150 static const int ip_stf_ttl = 40; 151 152 extern struct domain inetdomain; 153 static int in_stf_input(struct mbuf **, int *, int); 154 static struct protosw in_stf_protosw = { 155 .pr_type = SOCK_RAW, 156 .pr_domain = &inetdomain, 157 .pr_protocol = IPPROTO_IPV6, 158 .pr_flags = PR_ATOMIC|PR_ADDR, 159 .pr_input = in_stf_input, 160 .pr_output = rip_output, 161 .pr_ctloutput = rip_ctloutput, 162 .pr_usrreqs = &rip_usrreqs 163 }; 164 165 static char *stfnames[] = {"stf0", "stf", "6to4", NULL}; 166 167 static int stfmodevent(module_t, int, void *); 168 static int stf_encapcheck(const struct mbuf *, int, int, void *); 169 static int stf_getsrcifa6(struct ifnet *, struct in6_addr *, struct in6_addr *); 170 static int stf_output(struct ifnet *, struct mbuf *, const struct sockaddr *, 171 struct route *); 172 static int isrfc1918addr(struct in_addr *); 173 static int stf_checkaddr4(struct stf_softc *, struct in_addr *, 174 struct ifnet *); 175 static int stf_checkaddr6(struct stf_softc *, struct in6_addr *, 176 struct ifnet *); 177 static int stf_ioctl(struct ifnet *, u_long, caddr_t); 178 179 static int stf_clone_match(struct if_clone *, const char *); 180 static int stf_clone_create(struct if_clone *, char *, size_t, caddr_t); 181 static int stf_clone_destroy(struct if_clone *, struct ifnet *); 182 static struct if_clone *stf_cloner; 183 184 static int 185 stf_clone_match(struct if_clone *ifc, const char *name) 186 { 187 int i; 188 189 for(i = 0; stfnames[i] != NULL; i++) { 190 if (strcmp(stfnames[i], name) == 0) 191 return (1); 192 } 193 194 return (0); 195 } 196 197 static int 198 stf_clone_create(struct if_clone *ifc, char *name, size_t len, caddr_t params) 199 { 200 char *dp; 201 int err, unit, wildcard; 202 struct stf_softc *sc; 203 struct ifnet *ifp; 204 205 err = ifc_name2unit(name, &unit); 206 if (err != 0) 207 return (err); 208 wildcard = (unit < 0); 209 210 /* 211 * We can only have one unit, but since unit allocation is 212 * already locked, we use it to keep from allocating extra 213 * interfaces. 214 */ 215 unit = STFUNIT; 216 err = ifc_alloc_unit(ifc, &unit); 217 if (err != 0) 218 return (err); 219 220 sc = malloc(sizeof(struct stf_softc), M_STF, M_WAITOK | M_ZERO); 221 ifp = STF2IFP(sc) = if_alloc(IFT_STF); 222 if (ifp == NULL) { 223 free(sc, M_STF); 224 ifc_free_unit(ifc, unit); 225 return (ENOSPC); 226 } 227 ifp->if_softc = sc; 228 sc->sc_fibnum = curthread->td_proc->p_fibnum; 229 230 /* 231 * Set the name manually rather then using if_initname because 232 * we don't conform to the default naming convention for interfaces. 233 * In the wildcard case, we need to update the name. 234 */ 235 if (wildcard) { 236 for (dp = name; *dp != '\0'; dp++); 237 if (snprintf(dp, len - (dp-name), "%d", unit) > 238 len - (dp-name) - 1) { 239 /* 240 * This can only be a programmer error and 241 * there's no straightforward way to recover if 242 * it happens. 243 */ 244 panic("if_clone_create(): interface name too long"); 245 } 246 } 247 strlcpy(ifp->if_xname, name, IFNAMSIZ); 248 ifp->if_dname = stfname; 249 ifp->if_dunit = IF_DUNIT_NONE; 250 251 sc->encap_cookie = encap_attach_func(AF_INET, IPPROTO_IPV6, 252 stf_encapcheck, &in_stf_protosw, sc); 253 if (sc->encap_cookie == NULL) { 254 if_printf(ifp, "attach failed\n"); 255 free(sc, M_STF); 256 ifc_free_unit(ifc, unit); 257 return (ENOMEM); 258 } 259 260 ifp->if_mtu = IPV6_MMTU; 261 ifp->if_ioctl = stf_ioctl; 262 ifp->if_output = stf_output; 263 ifp->if_snd.ifq_maxlen = ifqmaxlen; 264 if_attach(ifp); 265 bpfattach(ifp, DLT_NULL, sizeof(u_int32_t)); 266 return (0); 267 } 268 269 static int 270 stf_clone_destroy(struct if_clone *ifc, struct ifnet *ifp) 271 { 272 struct stf_softc *sc = ifp->if_softc; 273 int err; 274 275 err = encap_detach(sc->encap_cookie); 276 KASSERT(err == 0, ("Unexpected error detaching encap_cookie")); 277 bpfdetach(ifp); 278 if_detach(ifp); 279 if_free(ifp); 280 281 free(sc, M_STF); 282 ifc_free_unit(ifc, STFUNIT); 283 284 return (0); 285 } 286 287 static int 288 stfmodevent(module_t mod, int type, void *data) 289 { 290 291 switch (type) { 292 case MOD_LOAD: 293 stf_cloner = if_clone_advanced(stfname, 0, stf_clone_match, 294 stf_clone_create, stf_clone_destroy); 295 break; 296 case MOD_UNLOAD: 297 if_clone_detach(stf_cloner); 298 break; 299 default: 300 return (EOPNOTSUPP); 301 } 302 303 return (0); 304 } 305 306 static moduledata_t stf_mod = { 307 "if_stf", 308 stfmodevent, 309 0 310 }; 311 312 DECLARE_MODULE(if_stf, stf_mod, SI_SUB_PSEUDO, SI_ORDER_ANY); 313 314 static int 315 stf_encapcheck(const struct mbuf *m, int off, int proto, void *arg) 316 { 317 struct ip ip; 318 struct stf_softc *sc; 319 struct in_addr a, b, mask; 320 struct in6_addr addr6, mask6; 321 322 sc = (struct stf_softc *)arg; 323 if (sc == NULL) 324 return 0; 325 326 if ((STF2IFP(sc)->if_flags & IFF_UP) == 0) 327 return 0; 328 329 /* IFF_LINK0 means "no decapsulation" */ 330 if ((STF2IFP(sc)->if_flags & IFF_LINK0) != 0) 331 return 0; 332 333 if (proto != IPPROTO_IPV6) 334 return 0; 335 336 m_copydata(m, 0, sizeof(ip), (caddr_t)&ip); 337 338 if (ip.ip_v != 4) 339 return 0; 340 341 if (stf_getsrcifa6(STF2IFP(sc), &addr6, &mask6) != 0) 342 return (0); 343 344 /* 345 * check if IPv4 dst matches the IPv4 address derived from the 346 * local 6to4 address. 347 * success on: dst = 10.1.1.1, ia6->ia_addr = 2002:0a01:0101:... 348 */ 349 if (bcmp(GET_V4(&addr6), &ip.ip_dst, sizeof(ip.ip_dst)) != 0) 350 return 0; 351 352 /* 353 * check if IPv4 src matches the IPv4 address derived from the 354 * local 6to4 address masked by prefixmask. 355 * success on: src = 10.1.1.1, ia6->ia_addr = 2002:0a00:.../24 356 * fail on: src = 10.1.1.1, ia6->ia_addr = 2002:0b00:.../24 357 */ 358 bzero(&a, sizeof(a)); 359 bcopy(GET_V4(&addr6), &a, sizeof(a)); 360 bcopy(GET_V4(&mask6), &mask, sizeof(mask)); 361 a.s_addr &= mask.s_addr; 362 b = ip.ip_src; 363 b.s_addr &= mask.s_addr; 364 if (a.s_addr != b.s_addr) 365 return 0; 366 367 /* stf interface makes single side match only */ 368 return 32; 369 } 370 371 static int 372 stf_getsrcifa6(struct ifnet *ifp, struct in6_addr *addr, struct in6_addr *mask) 373 { 374 struct ifaddr *ia; 375 struct in_ifaddr *ia4; 376 struct in6_ifaddr *ia6; 377 struct sockaddr_in6 *sin6; 378 struct in_addr in; 379 380 if_addr_rlock(ifp); 381 TAILQ_FOREACH(ia, &ifp->if_addrhead, ifa_link) { 382 if (ia->ifa_addr->sa_family != AF_INET6) 383 continue; 384 sin6 = (struct sockaddr_in6 *)ia->ifa_addr; 385 if (!IN6_IS_ADDR_6TO4(&sin6->sin6_addr)) 386 continue; 387 388 bcopy(GET_V4(&sin6->sin6_addr), &in, sizeof(in)); 389 LIST_FOREACH(ia4, INADDR_HASH(in.s_addr), ia_hash) 390 if (ia4->ia_addr.sin_addr.s_addr == in.s_addr) 391 break; 392 if (ia4 == NULL) 393 continue; 394 395 ia6 = (struct in6_ifaddr *)ia; 396 397 *addr = sin6->sin6_addr; 398 *mask = ia6->ia_prefixmask.sin6_addr; 399 if_addr_runlock(ifp); 400 return (0); 401 } 402 if_addr_runlock(ifp); 403 404 return (ENOENT); 405 } 406 407 static int 408 stf_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst, 409 struct route *ro) 410 { 411 struct stf_softc *sc; 412 const struct sockaddr_in6 *dst6; 413 struct in_addr in4; 414 const void *ptr; 415 u_int8_t tos; 416 struct ip *ip; 417 struct ip6_hdr *ip6; 418 struct in6_addr addr6, mask6; 419 int error; 420 421 #ifdef MAC 422 error = mac_ifnet_check_transmit(ifp, m); 423 if (error) { 424 m_freem(m); 425 return (error); 426 } 427 #endif 428 429 sc = ifp->if_softc; 430 dst6 = (const struct sockaddr_in6 *)dst; 431 432 /* just in case */ 433 if ((ifp->if_flags & IFF_UP) == 0) { 434 m_freem(m); 435 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 436 return ENETDOWN; 437 } 438 439 /* 440 * If we don't have an ip4 address that match my inner ip6 address, 441 * we shouldn't generate output. Without this check, we'll end up 442 * using wrong IPv4 source. 443 */ 444 if (stf_getsrcifa6(ifp, &addr6, &mask6) != 0) { 445 m_freem(m); 446 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 447 return ENETDOWN; 448 } 449 450 if (m->m_len < sizeof(*ip6)) { 451 m = m_pullup(m, sizeof(*ip6)); 452 if (!m) { 453 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 454 return ENOBUFS; 455 } 456 } 457 ip6 = mtod(m, struct ip6_hdr *); 458 tos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; 459 460 /* 461 * Pickup the right outer dst addr from the list of candidates. 462 * ip6_dst has priority as it may be able to give us shorter IPv4 hops. 463 */ 464 ptr = NULL; 465 if (IN6_IS_ADDR_6TO4(&ip6->ip6_dst)) 466 ptr = GET_V4(&ip6->ip6_dst); 467 else if (IN6_IS_ADDR_6TO4(&dst6->sin6_addr)) 468 ptr = GET_V4(&dst6->sin6_addr); 469 else { 470 m_freem(m); 471 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 472 return ENETUNREACH; 473 } 474 bcopy(ptr, &in4, sizeof(in4)); 475 476 if (bpf_peers_present(ifp->if_bpf)) { 477 /* 478 * We need to prepend the address family as 479 * a four byte field. Cons up a dummy header 480 * to pacify bpf. This is safe because bpf 481 * will only read from the mbuf (i.e., it won't 482 * try to free it or keep a pointer a to it). 483 */ 484 u_int af = AF_INET6; 485 bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m); 486 } 487 488 M_PREPEND(m, sizeof(struct ip), M_NOWAIT); 489 if (m == NULL) { 490 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 491 return ENOBUFS; 492 } 493 ip = mtod(m, struct ip *); 494 495 bzero(ip, sizeof(*ip)); 496 497 bcopy(GET_V4(&addr6), &ip->ip_src, sizeof(ip->ip_src)); 498 bcopy(&in4, &ip->ip_dst, sizeof(ip->ip_dst)); 499 ip->ip_p = IPPROTO_IPV6; 500 ip->ip_ttl = ip_stf_ttl; 501 ip->ip_len = htons(m->m_pkthdr.len); 502 if (ifp->if_flags & IFF_LINK1) 503 ip_ecn_ingress(ECN_ALLOWED, &ip->ip_tos, &tos); 504 else 505 ip_ecn_ingress(ECN_NOCARE, &ip->ip_tos, &tos); 506 507 M_SETFIB(m, sc->sc_fibnum); 508 if_inc_counter(ifp, IFCOUNTER_OPACKETS, 1); 509 error = ip_output(m, NULL, NULL, 0, NULL, NULL); 510 511 return error; 512 } 513 514 static int 515 isrfc1918addr(struct in_addr *in) 516 { 517 /* 518 * returns 1 if private address range: 519 * 10.0.0.0/8 172.16.0.0/12 192.168.0.0/16 520 */ 521 if (stf_permit_rfc1918 == 0 && ( 522 (ntohl(in->s_addr) & 0xff000000) >> 24 == 10 || 523 (ntohl(in->s_addr) & 0xfff00000) >> 16 == 172 * 256 + 16 || 524 (ntohl(in->s_addr) & 0xffff0000) >> 16 == 192 * 256 + 168)) 525 return 1; 526 527 return 0; 528 } 529 530 static int 531 stf_checkaddr4(struct stf_softc *sc, struct in_addr *in, struct ifnet *inifp) 532 { 533 struct rm_priotracker in_ifa_tracker; 534 struct in_ifaddr *ia4; 535 536 /* 537 * reject packets with the following address: 538 * 224.0.0.0/4 0.0.0.0/8 127.0.0.0/8 255.0.0.0/8 539 */ 540 if (IN_MULTICAST(ntohl(in->s_addr))) 541 return -1; 542 switch ((ntohl(in->s_addr) & 0xff000000) >> 24) { 543 case 0: case 127: case 255: 544 return -1; 545 } 546 547 /* 548 * reject packets with private address range. 549 * (requirement from RFC3056 section 2 1st paragraph) 550 */ 551 if (isrfc1918addr(in)) 552 return -1; 553 554 /* 555 * reject packets with broadcast 556 */ 557 IN_IFADDR_RLOCK(&in_ifa_tracker); 558 TAILQ_FOREACH(ia4, &V_in_ifaddrhead, ia_link) { 559 if ((ia4->ia_ifa.ifa_ifp->if_flags & IFF_BROADCAST) == 0) 560 continue; 561 if (in->s_addr == ia4->ia_broadaddr.sin_addr.s_addr) { 562 IN_IFADDR_RUNLOCK(&in_ifa_tracker); 563 return -1; 564 } 565 } 566 IN_IFADDR_RUNLOCK(&in_ifa_tracker); 567 568 /* 569 * perform ingress filter 570 */ 571 if (sc && (STF2IFP(sc)->if_flags & IFF_LINK2) == 0 && inifp) { 572 struct nhop4_basic nh4; 573 574 if (fib4_lookup_nh_basic(sc->sc_fibnum, *in, 0, 0, &nh4) != 0) 575 return (-1); 576 577 if (nh4.nh_ifp != inifp) 578 return (-1); 579 } 580 581 return 0; 582 } 583 584 static int 585 stf_checkaddr6(struct stf_softc *sc, struct in6_addr *in6, struct ifnet *inifp) 586 { 587 /* 588 * check 6to4 addresses 589 */ 590 if (IN6_IS_ADDR_6TO4(in6)) { 591 struct in_addr in4; 592 bcopy(GET_V4(in6), &in4, sizeof(in4)); 593 return stf_checkaddr4(sc, &in4, inifp); 594 } 595 596 /* 597 * reject anything that look suspicious. the test is implemented 598 * in ip6_input too, but we check here as well to 599 * (1) reject bad packets earlier, and 600 * (2) to be safe against future ip6_input change. 601 */ 602 if (IN6_IS_ADDR_V4COMPAT(in6) || IN6_IS_ADDR_V4MAPPED(in6)) 603 return -1; 604 605 return 0; 606 } 607 608 static int 609 in_stf_input(struct mbuf **mp, int *offp, int proto) 610 { 611 struct stf_softc *sc; 612 struct ip *ip; 613 struct ip6_hdr *ip6; 614 struct mbuf *m; 615 u_int8_t otos, itos; 616 struct ifnet *ifp; 617 int off; 618 619 m = *mp; 620 off = *offp; 621 622 if (proto != IPPROTO_IPV6) { 623 m_freem(m); 624 return (IPPROTO_DONE); 625 } 626 627 ip = mtod(m, struct ip *); 628 629 sc = (struct stf_softc *)encap_getarg(m); 630 631 if (sc == NULL || (STF2IFP(sc)->if_flags & IFF_UP) == 0) { 632 m_freem(m); 633 return (IPPROTO_DONE); 634 } 635 636 ifp = STF2IFP(sc); 637 638 #ifdef MAC 639 mac_ifnet_create_mbuf(ifp, m); 640 #endif 641 642 /* 643 * perform sanity check against outer src/dst. 644 * for source, perform ingress filter as well. 645 */ 646 if (stf_checkaddr4(sc, &ip->ip_dst, NULL) < 0 || 647 stf_checkaddr4(sc, &ip->ip_src, m->m_pkthdr.rcvif) < 0) { 648 m_freem(m); 649 return (IPPROTO_DONE); 650 } 651 652 otos = ip->ip_tos; 653 m_adj(m, off); 654 655 if (m->m_len < sizeof(*ip6)) { 656 m = m_pullup(m, sizeof(*ip6)); 657 if (!m) 658 return (IPPROTO_DONE); 659 } 660 ip6 = mtod(m, struct ip6_hdr *); 661 662 /* 663 * perform sanity check against inner src/dst. 664 * for source, perform ingress filter as well. 665 */ 666 if (stf_checkaddr6(sc, &ip6->ip6_dst, NULL) < 0 || 667 stf_checkaddr6(sc, &ip6->ip6_src, m->m_pkthdr.rcvif) < 0) { 668 m_freem(m); 669 return (IPPROTO_DONE); 670 } 671 672 itos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; 673 if ((ifp->if_flags & IFF_LINK1) != 0) 674 ip_ecn_egress(ECN_ALLOWED, &otos, &itos); 675 else 676 ip_ecn_egress(ECN_NOCARE, &otos, &itos); 677 ip6->ip6_flow &= ~htonl(0xff << 20); 678 ip6->ip6_flow |= htonl((u_int32_t)itos << 20); 679 680 m->m_pkthdr.rcvif = ifp; 681 682 if (bpf_peers_present(ifp->if_bpf)) { 683 /* 684 * We need to prepend the address family as 685 * a four byte field. Cons up a dummy header 686 * to pacify bpf. This is safe because bpf 687 * will only read from the mbuf (i.e., it won't 688 * try to free it or keep a pointer a to it). 689 */ 690 u_int32_t af = AF_INET6; 691 bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m); 692 } 693 694 /* 695 * Put the packet to the network layer input queue according to the 696 * specified address family. 697 * See net/if_gif.c for possible issues with packet processing 698 * reorder due to extra queueing. 699 */ 700 if_inc_counter(ifp, IFCOUNTER_IPACKETS, 1); 701 if_inc_counter(ifp, IFCOUNTER_IBYTES, m->m_pkthdr.len); 702 M_SETFIB(m, ifp->if_fib); 703 netisr_dispatch(NETISR_IPV6, m); 704 return (IPPROTO_DONE); 705 } 706 707 static int 708 stf_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data) 709 { 710 struct ifaddr *ifa; 711 struct ifreq *ifr; 712 struct sockaddr_in6 *sin6; 713 struct in_addr addr; 714 int error, mtu; 715 716 error = 0; 717 switch (cmd) { 718 case SIOCSIFADDR: 719 ifa = (struct ifaddr *)data; 720 if (ifa == NULL || ifa->ifa_addr->sa_family != AF_INET6) { 721 error = EAFNOSUPPORT; 722 break; 723 } 724 sin6 = (struct sockaddr_in6 *)ifa->ifa_addr; 725 if (!IN6_IS_ADDR_6TO4(&sin6->sin6_addr)) { 726 error = EINVAL; 727 break; 728 } 729 bcopy(GET_V4(&sin6->sin6_addr), &addr, sizeof(addr)); 730 if (isrfc1918addr(&addr)) { 731 error = EINVAL; 732 break; 733 } 734 735 ifp->if_flags |= IFF_UP; 736 break; 737 738 case SIOCADDMULTI: 739 case SIOCDELMULTI: 740 ifr = (struct ifreq *)data; 741 if (ifr && ifr->ifr_addr.sa_family == AF_INET6) 742 ; 743 else 744 error = EAFNOSUPPORT; 745 break; 746 747 case SIOCGIFMTU: 748 break; 749 750 case SIOCSIFMTU: 751 ifr = (struct ifreq *)data; 752 mtu = ifr->ifr_mtu; 753 /* RFC 4213 3.2 ideal world MTU */ 754 if (mtu < IPV6_MINMTU || mtu > IF_MAXMTU - 20) 755 return (EINVAL); 756 ifp->if_mtu = mtu; 757 break; 758 759 default: 760 error = EINVAL; 761 break; 762 } 763 764 return error; 765 } 766