if_stf.c revision 183351
1/* $FreeBSD: head/sys/net/if_stf.c 183351 2008-09-25 12:35:01Z dwmalone $ */ 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 "opt_inet.h" 78#include "opt_inet6.h" 79#include "opt_mac.h" 80 81#include <sys/param.h> 82#include <sys/systm.h> 83#include <sys/socket.h> 84#include <sys/sockio.h> 85#include <sys/mbuf.h> 86#include <sys/errno.h> 87#include <sys/kernel.h> 88#include <sys/module.h> 89#include <sys/protosw.h> 90#include <sys/proc.h> 91#include <sys/queue.h> 92#include <sys/sysctl.h> 93#include <machine/cpu.h> 94 95#include <sys/malloc.h> 96#include <sys/vimage.h> 97 98#include <net/if.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/if_stf.h> 104 105#include <netinet/in.h> 106#include <netinet/in_systm.h> 107#include <netinet/ip.h> 108#include <netinet/ip_var.h> 109#include <netinet/in_var.h> 110 111#include <netinet/ip6.h> 112#include <netinet6/ip6_var.h> 113#include <netinet6/in6_var.h> 114#include <netinet/ip_ecn.h> 115 116#include <netinet/ip_encap.h> 117 118#include <machine/stdarg.h> 119 120#include <net/bpf.h> 121 122#include <security/mac/mac_framework.h> 123 124SYSCTL_DECL(_net_link); 125SYSCTL_NODE(_net_link, IFT_STF, stf, CTLFLAG_RW, 0, "6to4 Interface"); 126 127static int stf_route_cache = 1; 128SYSCTL_INT(_net_link_stf, OID_AUTO, route_cache, CTLFLAG_RW, 129 &stf_route_cache, 0, "Caching of IPv4 routes for 6to4 Output"); 130 131#define STFNAME "stf" 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) ((caddr_t)(&(x)->s6_addr16[1])) 141 142struct stf_softc { 143 struct ifnet *sc_ifp; 144 union { 145 struct route __sc_ro4; 146 struct route_in6 __sc_ro6; /* just for safety */ 147 } __sc_ro46; 148#define sc_ro __sc_ro46.__sc_ro4 149 struct mtx sc_ro_mtx; 150 u_int sc_fibnum; 151 const struct encaptab *encap_cookie; 152}; 153#define STF2IFP(sc) ((sc)->sc_ifp) 154 155/* 156 * Note that mutable fields in the softc are not currently locked. 157 * We do lock sc_ro in stf_output though. 158 */ 159static MALLOC_DEFINE(M_STF, STFNAME, "6to4 Tunnel Interface"); 160static const int ip_stf_ttl = 40; 161 162extern struct domain inetdomain; 163struct protosw in_stf_protosw = { 164 .pr_type = SOCK_RAW, 165 .pr_domain = &inetdomain, 166 .pr_protocol = IPPROTO_IPV6, 167 .pr_flags = PR_ATOMIC|PR_ADDR, 168 .pr_input = in_stf_input, 169 .pr_output = (pr_output_t *)rip_output, 170 .pr_ctloutput = rip_ctloutput, 171 .pr_usrreqs = &rip_usrreqs 172}; 173 174static char *stfnames[] = {"stf0", "stf", "6to4", NULL}; 175 176static int stfmodevent(module_t, int, void *); 177static int stf_encapcheck(const struct mbuf *, int, int, void *); 178static struct in6_ifaddr *stf_getsrcifa6(struct ifnet *); 179static int stf_output(struct ifnet *, struct mbuf *, struct sockaddr *, 180 struct rtentry *); 181static int isrfc1918addr(struct in_addr *); 182static int stf_checkaddr4(struct stf_softc *, struct in_addr *, 183 struct ifnet *); 184static int stf_checkaddr6(struct stf_softc *, struct in6_addr *, 185 struct ifnet *); 186static void stf_rtrequest(int, struct rtentry *, struct rt_addrinfo *); 187static int stf_ioctl(struct ifnet *, u_long, caddr_t); 188 189static int stf_clone_match(struct if_clone *, const char *); 190static int stf_clone_create(struct if_clone *, char *, size_t, caddr_t); 191static int stf_clone_destroy(struct if_clone *, struct ifnet *); 192struct if_clone stf_cloner = IFC_CLONE_INITIALIZER(STFNAME, NULL, 0, 193 NULL, stf_clone_match, stf_clone_create, stf_clone_destroy); 194 195static int 196stf_clone_match(struct if_clone *ifc, const char *name) 197{ 198 int i; 199 200 for(i = 0; stfnames[i] != NULL; i++) { 201 if (strcmp(stfnames[i], name) == 0) 202 return (1); 203 } 204 205 return (0); 206} 207 208static int 209stf_clone_create(struct if_clone *ifc, char *name, size_t len, caddr_t params) 210{ 211 int err, unit; 212 struct stf_softc *sc; 213 struct ifnet *ifp; 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 */ 239 strlcpy(ifp->if_xname, name, IFNAMSIZ); 240 ifp->if_dname = ifc->ifc_name; 241 ifp->if_dunit = IF_DUNIT_NONE; 242 243 mtx_init(&(sc)->sc_ro_mtx, "stf ro", NULL, MTX_DEF); 244 sc->encap_cookie = encap_attach_func(AF_INET, IPPROTO_IPV6, 245 stf_encapcheck, &in_stf_protosw, sc); 246 if (sc->encap_cookie == NULL) { 247 if_printf(ifp, "attach failed\n"); 248 free(sc, M_STF); 249 ifc_free_unit(ifc, unit); 250 return (ENOMEM); 251 } 252 253 ifp->if_mtu = IPV6_MMTU; 254 ifp->if_ioctl = stf_ioctl; 255 ifp->if_output = stf_output; 256 ifp->if_snd.ifq_maxlen = IFQ_MAXLEN; 257 if_attach(ifp); 258 bpfattach(ifp, DLT_NULL, sizeof(u_int32_t)); 259 return (0); 260} 261 262static int 263stf_clone_destroy(struct if_clone *ifc, struct ifnet *ifp) 264{ 265 struct stf_softc *sc = ifp->if_softc; 266 int err; 267 268 err = encap_detach(sc->encap_cookie); 269 KASSERT(err == 0, ("Unexpected error detaching encap_cookie")); 270 mtx_destroy(&(sc)->sc_ro_mtx); 271 bpfdetach(ifp); 272 if_detach(ifp); 273 if_free(ifp); 274 275 free(sc, M_STF); 276 ifc_free_unit(ifc, STFUNIT); 277 278 return (0); 279} 280 281static int 282stfmodevent(mod, type, data) 283 module_t mod; 284 int type; 285 void *data; 286{ 287 288 switch (type) { 289 case MOD_LOAD: 290 if_clone_attach(&stf_cloner); 291 break; 292 case MOD_UNLOAD: 293 if_clone_detach(&stf_cloner); 294 break; 295 default: 296 return (EOPNOTSUPP); 297 } 298 299 return (0); 300} 301 302static moduledata_t stf_mod = { 303 "if_stf", 304 stfmodevent, 305 0 306}; 307 308DECLARE_MODULE(if_stf, stf_mod, SI_SUB_PSEUDO, SI_ORDER_ANY); 309 310static int 311stf_encapcheck(m, off, proto, arg) 312 const struct mbuf *m; 313 int off; 314 int proto; 315 void *arg; 316{ 317 struct ip ip; 318 struct in6_ifaddr *ia6; 319 struct stf_softc *sc; 320 struct in_addr a, b, mask; 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 /* LINTED const cast */ 337 m_copydata((struct mbuf *)(uintptr_t)m, 0, sizeof(ip), (caddr_t)&ip); 338 339 if (ip.ip_v != 4) 340 return 0; 341 342 ia6 = stf_getsrcifa6(STF2IFP(sc)); 343 if (ia6 == NULL) 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(&ia6->ia_addr.sin6_addr), &ip.ip_dst, 352 sizeof(ip.ip_dst)) != 0) 353 return 0; 354 355 /* 356 * check if IPv4 src matches the IPv4 address derived from the 357 * local 6to4 address masked by prefixmask. 358 * success on: src = 10.1.1.1, ia6->ia_addr = 2002:0a00:.../24 359 * fail on: src = 10.1.1.1, ia6->ia_addr = 2002:0b00:.../24 360 */ 361 bzero(&a, sizeof(a)); 362 bcopy(GET_V4(&ia6->ia_addr.sin6_addr), &a, sizeof(a)); 363 bcopy(GET_V4(&ia6->ia_prefixmask.sin6_addr), &mask, sizeof(mask)); 364 a.s_addr &= mask.s_addr; 365 b = ip.ip_src; 366 b.s_addr &= mask.s_addr; 367 if (a.s_addr != b.s_addr) 368 return 0; 369 370 /* stf interface makes single side match only */ 371 return 32; 372} 373 374static struct in6_ifaddr * 375stf_getsrcifa6(ifp) 376 struct ifnet *ifp; 377{ 378 struct ifaddr *ia; 379 struct in_ifaddr *ia4; 380 struct sockaddr_in6 *sin6; 381 struct in_addr in; 382 383 TAILQ_FOREACH(ia, &ifp->if_addrlist, ifa_list) { 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 return (struct in6_ifaddr *)ia; 398 } 399 400 return NULL; 401} 402 403static int 404stf_output(ifp, m, dst, rt) 405 struct ifnet *ifp; 406 struct mbuf *m; 407 struct sockaddr *dst; 408 struct rtentry *rt; 409{ 410 struct stf_softc *sc; 411 struct sockaddr_in6 *dst6; 412 struct route *cached_route; 413 struct in_addr in4; 414 caddr_t ptr; 415 struct sockaddr_in *dst4; 416 u_int8_t tos; 417 struct ip *ip; 418 struct ip6_hdr *ip6; 419 struct in6_ifaddr *ia6; 420 u_int32_t af; 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 = (struct sockaddr_in6 *)dst; 433 434 /* just in case */ 435 if ((ifp->if_flags & IFF_UP) == 0) { 436 m_freem(m); 437 ifp->if_oerrors++; 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 ia6 = stf_getsrcifa6(ifp); 447 if (ia6 == NULL) { 448 m_freem(m); 449 ifp->if_oerrors++; 450 return ENETDOWN; 451 } 452 453 if (m->m_len < sizeof(*ip6)) { 454 m = m_pullup(m, sizeof(*ip6)); 455 if (!m) { 456 ifp->if_oerrors++; 457 return ENOBUFS; 458 } 459 } 460 ip6 = mtod(m, struct ip6_hdr *); 461 tos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; 462 463 /* 464 * BPF writes need to be handled specially. 465 * This is a null operation, nothing here checks dst->sa_family. 466 */ 467 if (dst->sa_family == AF_UNSPEC) { 468 bcopy(dst->sa_data, &af, sizeof(af)); 469 dst->sa_family = af; 470 } 471 472 /* 473 * Pickup the right outer dst addr from the list of candidates. 474 * ip6_dst has priority as it may be able to give us shorter IPv4 hops. 475 */ 476 ptr = NULL; 477 if (IN6_IS_ADDR_6TO4(&ip6->ip6_dst)) 478 ptr = GET_V4(&ip6->ip6_dst); 479 else if (IN6_IS_ADDR_6TO4(&dst6->sin6_addr)) 480 ptr = GET_V4(&dst6->sin6_addr); 481 else { 482 m_freem(m); 483 ifp->if_oerrors++; 484 return ENETUNREACH; 485 } 486 bcopy(ptr, &in4, sizeof(in4)); 487 488 if (bpf_peers_present(ifp->if_bpf)) { 489 /* 490 * We need to prepend the address family as 491 * a four byte field. Cons up a dummy header 492 * to pacify bpf. This is safe because bpf 493 * will only read from the mbuf (i.e., it won't 494 * try to free it or keep a pointer a to it). 495 */ 496 af = AF_INET6; 497 bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m); 498 } 499 500 M_PREPEND(m, sizeof(struct ip), M_DONTWAIT); 501 if (m && m->m_len < sizeof(struct ip)) 502 m = m_pullup(m, sizeof(struct ip)); 503 if (m == NULL) { 504 ifp->if_oerrors++; 505 return ENOBUFS; 506 } 507 ip = mtod(m, struct ip *); 508 509 bzero(ip, sizeof(*ip)); 510 511 bcopy(GET_V4(&((struct sockaddr_in6 *)&ia6->ia_addr)->sin6_addr), 512 &ip->ip_src, sizeof(ip->ip_src)); 513 bcopy(&in4, &ip->ip_dst, sizeof(ip->ip_dst)); 514 ip->ip_p = IPPROTO_IPV6; 515 ip->ip_ttl = ip_stf_ttl; 516 ip->ip_len = m->m_pkthdr.len; /*host order*/ 517 if (ifp->if_flags & IFF_LINK1) 518 ip_ecn_ingress(ECN_ALLOWED, &ip->ip_tos, &tos); 519 else 520 ip_ecn_ingress(ECN_NOCARE, &ip->ip_tos, &tos); 521 522 if (!stf_route_cache) { 523 cached_route = NULL; 524 goto sendit; 525 } 526 527 /* 528 * Do we have a cached route? 529 */ 530 mtx_lock(&(sc)->sc_ro_mtx); 531 dst4 = (struct sockaddr_in *)&sc->sc_ro.ro_dst; 532 if (dst4->sin_family != AF_INET || 533 bcmp(&dst4->sin_addr, &ip->ip_dst, sizeof(ip->ip_dst)) != 0) { 534 /* cache route doesn't match */ 535 dst4->sin_family = AF_INET; 536 dst4->sin_len = sizeof(struct sockaddr_in); 537 bcopy(&ip->ip_dst, &dst4->sin_addr, sizeof(dst4->sin_addr)); 538 if (sc->sc_ro.ro_rt) { 539 RTFREE(sc->sc_ro.ro_rt); 540 sc->sc_ro.ro_rt = NULL; 541 } 542 } 543 544 if (sc->sc_ro.ro_rt == NULL) { 545 rtalloc_fib(&sc->sc_ro, sc->sc_fibnum); 546 if (sc->sc_ro.ro_rt == NULL) { 547 m_freem(m); 548 mtx_unlock(&(sc)->sc_ro_mtx); 549 ifp->if_oerrors++; 550 return ENETUNREACH; 551 } 552 } 553 cached_route = &sc->sc_ro; 554 555sendit: 556 M_SETFIB(m, sc->sc_fibnum); 557 ifp->if_opackets++; 558 error = ip_output(m, NULL, cached_route, 0, NULL, NULL); 559 560 if (cached_route != NULL) 561 mtx_unlock(&(sc)->sc_ro_mtx); 562 return error; 563} 564 565static int 566isrfc1918addr(in) 567 struct in_addr *in; 568{ 569 /* 570 * returns 1 if private address range: 571 * 10.0.0.0/8 172.16.0.0/12 192.168.0.0/16 572 */ 573 if ((ntohl(in->s_addr) & 0xff000000) >> 24 == 10 || 574 (ntohl(in->s_addr) & 0xfff00000) >> 16 == 172 * 256 + 16 || 575 (ntohl(in->s_addr) & 0xffff0000) >> 16 == 192 * 256 + 168) 576 return 1; 577 578 return 0; 579} 580 581static int 582stf_checkaddr4(sc, in, inifp) 583 struct stf_softc *sc; 584 struct in_addr *in; 585 struct ifnet *inifp; /* incoming interface */ 586{ 587 struct in_ifaddr *ia4; 588 589 /* 590 * reject packets with the following address: 591 * 224.0.0.0/4 0.0.0.0/8 127.0.0.0/8 255.0.0.0/8 592 */ 593 if (IN_MULTICAST(ntohl(in->s_addr))) 594 return -1; 595 switch ((ntohl(in->s_addr) & 0xff000000) >> 24) { 596 case 0: case 127: case 255: 597 return -1; 598 } 599 600 /* 601 * reject packets with private address range. 602 * (requirement from RFC3056 section 2 1st paragraph) 603 */ 604 if (isrfc1918addr(in)) 605 return -1; 606 607 /* 608 * reject packets with broadcast 609 */ 610 for (ia4 = TAILQ_FIRST(&V_in_ifaddrhead); 611 ia4; 612 ia4 = TAILQ_NEXT(ia4, ia_link)) 613 { 614 if ((ia4->ia_ifa.ifa_ifp->if_flags & IFF_BROADCAST) == 0) 615 continue; 616 if (in->s_addr == ia4->ia_broadaddr.sin_addr.s_addr) 617 return -1; 618 } 619 620 /* 621 * perform ingress filter 622 */ 623 if (sc && (STF2IFP(sc)->if_flags & IFF_LINK2) == 0 && inifp) { 624 struct sockaddr_in sin; 625 struct rtentry *rt; 626 627 bzero(&sin, sizeof(sin)); 628 sin.sin_family = AF_INET; 629 sin.sin_len = sizeof(struct sockaddr_in); 630 sin.sin_addr = *in; 631 rt = rtalloc1_fib((struct sockaddr *)&sin, 0, 632 0UL, sc->sc_fibnum); 633 if (!rt || rt->rt_ifp != inifp) { 634#if 0 635 log(LOG_WARNING, "%s: packet from 0x%x dropped " 636 "due to ingress filter\n", if_name(STF2IFP(sc)), 637 (u_int32_t)ntohl(sin.sin_addr.s_addr)); 638#endif 639 if (rt) 640 RTFREE_LOCKED(rt); 641 return -1; 642 } 643 RTFREE_LOCKED(rt); 644 } 645 646 return 0; 647} 648 649static int 650stf_checkaddr6(sc, in6, inifp) 651 struct stf_softc *sc; 652 struct in6_addr *in6; 653 struct ifnet *inifp; /* incoming interface */ 654{ 655 /* 656 * check 6to4 addresses 657 */ 658 if (IN6_IS_ADDR_6TO4(in6)) { 659 struct in_addr in4; 660 bcopy(GET_V4(in6), &in4, sizeof(in4)); 661 return stf_checkaddr4(sc, &in4, inifp); 662 } 663 664 /* 665 * reject anything that look suspicious. the test is implemented 666 * in ip6_input too, but we check here as well to 667 * (1) reject bad packets earlier, and 668 * (2) to be safe against future ip6_input change. 669 */ 670 if (IN6_IS_ADDR_V4COMPAT(in6) || IN6_IS_ADDR_V4MAPPED(in6)) 671 return -1; 672 673 return 0; 674} 675 676void 677in_stf_input(m, off) 678 struct mbuf *m; 679 int off; 680{ 681 int proto; 682 struct stf_softc *sc; 683 struct ip *ip; 684 struct ip6_hdr *ip6; 685 u_int8_t otos, itos; 686 struct ifnet *ifp; 687 688 proto = mtod(m, struct ip *)->ip_p; 689 690 if (proto != IPPROTO_IPV6) { 691 m_freem(m); 692 return; 693 } 694 695 ip = mtod(m, struct ip *); 696 697 sc = (struct stf_softc *)encap_getarg(m); 698 699 if (sc == NULL || (STF2IFP(sc)->if_flags & IFF_UP) == 0) { 700 m_freem(m); 701 return; 702 } 703 704 ifp = STF2IFP(sc); 705 706#ifdef MAC 707 mac_ifnet_create_mbuf(ifp, m); 708#endif 709 710 /* 711 * perform sanity check against outer src/dst. 712 * for source, perform ingress filter as well. 713 */ 714 if (stf_checkaddr4(sc, &ip->ip_dst, NULL) < 0 || 715 stf_checkaddr4(sc, &ip->ip_src, m->m_pkthdr.rcvif) < 0) { 716 m_freem(m); 717 return; 718 } 719 720 otos = ip->ip_tos; 721 m_adj(m, off); 722 723 if (m->m_len < sizeof(*ip6)) { 724 m = m_pullup(m, sizeof(*ip6)); 725 if (!m) 726 return; 727 } 728 ip6 = mtod(m, struct ip6_hdr *); 729 730 /* 731 * perform sanity check against inner src/dst. 732 * for source, perform ingress filter as well. 733 */ 734 if (stf_checkaddr6(sc, &ip6->ip6_dst, NULL) < 0 || 735 stf_checkaddr6(sc, &ip6->ip6_src, m->m_pkthdr.rcvif) < 0) { 736 m_freem(m); 737 return; 738 } 739 740 itos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; 741 if ((ifp->if_flags & IFF_LINK1) != 0) 742 ip_ecn_egress(ECN_ALLOWED, &otos, &itos); 743 else 744 ip_ecn_egress(ECN_NOCARE, &otos, &itos); 745 ip6->ip6_flow &= ~htonl(0xff << 20); 746 ip6->ip6_flow |= htonl((u_int32_t)itos << 20); 747 748 m->m_pkthdr.rcvif = ifp; 749 750 if (bpf_peers_present(ifp->if_bpf)) { 751 /* 752 * We need to prepend the address family as 753 * a four byte field. Cons up a dummy header 754 * to pacify bpf. This is safe because bpf 755 * will only read from the mbuf (i.e., it won't 756 * try to free it or keep a pointer a to it). 757 */ 758 u_int32_t af = AF_INET6; 759 bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m); 760 } 761 762 /* 763 * Put the packet to the network layer input queue according to the 764 * specified address family. 765 * See net/if_gif.c for possible issues with packet processing 766 * reorder due to extra queueing. 767 */ 768 ifp->if_ipackets++; 769 ifp->if_ibytes += m->m_pkthdr.len; 770 netisr_dispatch(NETISR_IPV6, m); 771} 772 773/* ARGSUSED */ 774static void 775stf_rtrequest(cmd, rt, info) 776 int cmd; 777 struct rtentry *rt; 778 struct rt_addrinfo *info; 779{ 780 RT_LOCK_ASSERT(rt); 781 rt->rt_rmx.rmx_mtu = IPV6_MMTU; 782} 783 784static int 785stf_ioctl(ifp, cmd, data) 786 struct ifnet *ifp; 787 u_long cmd; 788 caddr_t data; 789{ 790 struct ifaddr *ifa; 791 struct ifreq *ifr; 792 struct sockaddr_in6 *sin6; 793 struct in_addr addr; 794 int error; 795 796 error = 0; 797 switch (cmd) { 798 case SIOCSIFADDR: 799 ifa = (struct ifaddr *)data; 800 if (ifa == NULL || ifa->ifa_addr->sa_family != AF_INET6) { 801 error = EAFNOSUPPORT; 802 break; 803 } 804 sin6 = (struct sockaddr_in6 *)ifa->ifa_addr; 805 if (!IN6_IS_ADDR_6TO4(&sin6->sin6_addr)) { 806 error = EINVAL; 807 break; 808 } 809 bcopy(GET_V4(&sin6->sin6_addr), &addr, sizeof(addr)); 810 if (isrfc1918addr(&addr)) { 811 error = EINVAL; 812 break; 813 } 814 815 ifa->ifa_rtrequest = stf_rtrequest; 816 ifp->if_flags |= IFF_UP; 817 break; 818 819 case SIOCADDMULTI: 820 case SIOCDELMULTI: 821 ifr = (struct ifreq *)data; 822 if (ifr && ifr->ifr_addr.sa_family == AF_INET6) 823 ; 824 else 825 error = EAFNOSUPPORT; 826 break; 827 828 default: 829 error = EINVAL; 830 break; 831 } 832 833 return error; 834} 835