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sys/net/if_stf.c
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1 /* $FreeBSD: releng/10.3/sys/net/if_stf.c 275828 2014-12-16 11:53:45Z ae $ */ 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 80 #include <sys/param.h> 81 #include <sys/systm.h> 82 #include <sys/socket.h> 83 #include <sys/sockio.h> 84 #include <sys/mbuf.h> 85 #include <sys/errno.h> 86 #include <sys/kernel.h> 87 #include <sys/module.h> 88 #include <sys/protosw.h> 89 #include <sys/proc.h> 90 #include <sys/queue.h> 91 #include <sys/sysctl.h> 92 #include <machine/cpu.h> 93 94 #include <sys/malloc.h> 95 96 #include <net/if.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/if_stf.h> 102 #include <net/vnet.h> 103 104 #include <netinet/in.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_route_cache = 1; 127 SYSCTL_INT(_net_link_stf, OID_AUTO, route_cache, CTLFLAG_RW, 128 &stf_route_cache, 0, "Caching of IPv4 routes for 6to4 Output"); 129 130 static int stf_permit_rfc1918 = 0; 131 TUNABLE_INT("net.link.stf.permit_rfc1918", &stf_permit_rfc1918); 132 SYSCTL_INT(_net_link_stf, OID_AUTO, permit_rfc1918, CTLFLAG_RW | CTLFLAG_TUN, 133 &stf_permit_rfc1918, 0, "Permit the use of private IPv4 addresses"); 134 135 #define STFUNIT 0 136 137 #define IN6_IS_ADDR_6TO4(x) (ntohs((x)->s6_addr16[0]) == 0x2002) 138 139 /* 140 * XXX: Return a pointer with 16-bit aligned. Don't cast it to 141 * struct in_addr *; use bcopy() instead. 142 */ 143 #define GET_V4(x) (&(x)->s6_addr16[1]) 144 145 struct stf_softc { 146 struct ifnet *sc_ifp; 147 union { 148 struct route __sc_ro4; 149 struct route_in6 __sc_ro6; /* just for safety */ 150 } __sc_ro46; 151 #define sc_ro __sc_ro46.__sc_ro4 152 struct mtx sc_ro_mtx; 153 u_int sc_fibnum; 154 const struct encaptab *encap_cookie; 155 }; 156 #define STF2IFP(sc) ((sc)->sc_ifp) 157 158 static const char stfname[] = "stf"; 159 160 /* 161 * Note that mutable fields in the softc are not currently locked. 162 * We do lock sc_ro in stf_output though. 163 */ 164 static MALLOC_DEFINE(M_STF, stfname, "6to4 Tunnel Interface"); 165 static const int ip_stf_ttl = 40; 166 167 extern struct domain inetdomain; 168 struct protosw in_stf_protosw = { 169 .pr_type = SOCK_RAW, 170 .pr_domain = &inetdomain, 171 .pr_protocol = IPPROTO_IPV6, 172 .pr_flags = PR_ATOMIC|PR_ADDR, 173 .pr_input = in_stf_input, 174 .pr_output = (pr_output_t *)rip_output, 175 .pr_ctloutput = rip_ctloutput, 176 .pr_usrreqs = &rip_usrreqs 177 }; 178 179 static char *stfnames[] = {"stf0", "stf", "6to4", NULL}; 180 181 static int stfmodevent(module_t, int, void *); 182 static int stf_encapcheck(const struct mbuf *, int, int, void *); 183 static struct in6_ifaddr *stf_getsrcifa6(struct ifnet *); 184 static int stf_output(struct ifnet *, struct mbuf *, const struct sockaddr *, 185 struct route *); 186 static int isrfc1918addr(struct in_addr *); 187 static int stf_checkaddr4(struct stf_softc *, struct in_addr *, 188 struct ifnet *); 189 static int stf_checkaddr6(struct stf_softc *, struct in6_addr *, 190 struct ifnet *); 191 static void stf_rtrequest(int, struct rtentry *, struct rt_addrinfo *); 192 static int stf_ioctl(struct ifnet *, u_long, caddr_t); 193 194 static int stf_clone_match(struct if_clone *, const char *); 195 static int stf_clone_create(struct if_clone *, char *, size_t, caddr_t); 196 static int stf_clone_destroy(struct if_clone *, struct ifnet *); 197 static struct if_clone *stf_cloner; 198 199 static int 200 stf_clone_match(struct if_clone *ifc, const char *name) 201 { 202 int i; 203 204 for(i = 0; stfnames[i] != NULL; i++) { 205 if (strcmp(stfnames[i], name) == 0) 206 return (1); 207 } 208 209 return (0); 210 } 211 212 static int 213 stf_clone_create(struct if_clone *ifc, char *name, size_t len, caddr_t params) 214 { 215 int err, unit; 216 struct stf_softc *sc; 217 struct ifnet *ifp; 218 219 /* 220 * We can only have one unit, but since unit allocation is 221 * already locked, we use it to keep from allocating extra 222 * interfaces. 223 */ 224 unit = STFUNIT; 225 err = ifc_alloc_unit(ifc, &unit); 226 if (err != 0) 227 return (err); 228 229 sc = malloc(sizeof(struct stf_softc), M_STF, M_WAITOK | M_ZERO); 230 ifp = STF2IFP(sc) = if_alloc(IFT_STF); 231 if (ifp == NULL) { 232 free(sc, M_STF); 233 ifc_free_unit(ifc, unit); 234 return (ENOSPC); 235 } 236 ifp->if_softc = sc; 237 sc->sc_fibnum = curthread->td_proc->p_fibnum; 238 239 /* 240 * Set the name manually rather then using if_initname because 241 * we don't conform to the default naming convention for interfaces. 242 */ 243 strlcpy(ifp->if_xname, name, IFNAMSIZ); 244 ifp->if_dname = stfname; 245 ifp->if_dunit = IF_DUNIT_NONE; 246 247 mtx_init(&(sc)->sc_ro_mtx, "stf ro", NULL, MTX_DEF); 248 sc->encap_cookie = encap_attach_func(AF_INET, IPPROTO_IPV6, 249 stf_encapcheck, &in_stf_protosw, sc); 250 if (sc->encap_cookie == NULL) { 251 if_printf(ifp, "attach failed\n"); 252 free(sc, M_STF); 253 ifc_free_unit(ifc, unit); 254 return (ENOMEM); 255 } 256 257 ifp->if_mtu = IPV6_MMTU; 258 ifp->if_ioctl = stf_ioctl; 259 ifp->if_output = stf_output; 260 ifp->if_snd.ifq_maxlen = ifqmaxlen; 261 if_attach(ifp); 262 bpfattach(ifp, DLT_NULL, sizeof(u_int32_t)); 263 return (0); 264 } 265 266 static int 267 stf_clone_destroy(struct if_clone *ifc, struct ifnet *ifp) 268 { 269 struct stf_softc *sc = ifp->if_softc; 270 int err; 271 272 err = encap_detach(sc->encap_cookie); 273 KASSERT(err == 0, ("Unexpected error detaching encap_cookie")); 274 mtx_destroy(&(sc)->sc_ro_mtx); 275 bpfdetach(ifp); 276 if_detach(ifp); 277 if_free(ifp); 278 279 free(sc, M_STF); 280 ifc_free_unit(ifc, STFUNIT); 281 282 return (0); 283 } 284 285 static int 286 stfmodevent(mod, type, data) 287 module_t mod; 288 int type; 289 void *data; 290 { 291 292 switch (type) { 293 case MOD_LOAD: 294 stf_cloner = if_clone_advanced(stfname, 0, stf_clone_match, 295 stf_clone_create, stf_clone_destroy); 296 break; 297 case MOD_UNLOAD: 298 if_clone_detach(stf_cloner); 299 break; 300 default: 301 return (EOPNOTSUPP); 302 } 303 304 return (0); 305 } 306 307 static moduledata_t stf_mod = { 308 "if_stf", 309 stfmodevent, 310 0 311 }; 312 313 DECLARE_MODULE(if_stf, stf_mod, SI_SUB_PSEUDO, SI_ORDER_ANY); 314 315 static int 316 stf_encapcheck(m, off, proto, arg) 317 const struct mbuf *m; 318 int off; 319 int proto; 320 void *arg; 321 { 322 struct ip ip; 323 struct in6_ifaddr *ia6; 324 struct stf_softc *sc; 325 struct in_addr a, b, mask; 326 327 sc = (struct stf_softc *)arg; 328 if (sc == NULL) 329 return 0; 330 331 if ((STF2IFP(sc)->if_flags & IFF_UP) == 0) 332 return 0; 333 334 /* IFF_LINK0 means "no decapsulation" */ 335 if ((STF2IFP(sc)->if_flags & IFF_LINK0) != 0) 336 return 0; 337 338 if (proto != IPPROTO_IPV6) 339 return 0; 340 341 /* LINTED const cast */ 342 m_copydata((struct mbuf *)(uintptr_t)m, 0, sizeof(ip), (caddr_t)&ip); 343 344 if (ip.ip_v != 4) 345 return 0; 346 347 ia6 = stf_getsrcifa6(STF2IFP(sc)); 348 if (ia6 == NULL) 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(&ia6->ia_addr.sin6_addr), &ip.ip_dst, 357 sizeof(ip.ip_dst)) != 0) { 358 ifa_free(&ia6->ia_ifa); 359 return 0; 360 } 361 362 /* 363 * check if IPv4 src matches the IPv4 address derived from the 364 * local 6to4 address masked by prefixmask. 365 * success on: src = 10.1.1.1, ia6->ia_addr = 2002:0a00:.../24 366 * fail on: src = 10.1.1.1, ia6->ia_addr = 2002:0b00:.../24 367 */ 368 bzero(&a, sizeof(a)); 369 bcopy(GET_V4(&ia6->ia_addr.sin6_addr), &a, sizeof(a)); 370 bcopy(GET_V4(&ia6->ia_prefixmask.sin6_addr), &mask, sizeof(mask)); 371 ifa_free(&ia6->ia_ifa); 372 a.s_addr &= mask.s_addr; 373 b = ip.ip_src; 374 b.s_addr &= mask.s_addr; 375 if (a.s_addr != b.s_addr) 376 return 0; 377 378 /* stf interface makes single side match only */ 379 return 32; 380 } 381 382 static struct in6_ifaddr * 383 stf_getsrcifa6(ifp) 384 struct ifnet *ifp; 385 { 386 struct ifaddr *ia; 387 struct in_ifaddr *ia4; 388 struct sockaddr_in6 *sin6; 389 struct in_addr in; 390 391 if_addr_rlock(ifp); 392 TAILQ_FOREACH(ia, &ifp->if_addrhead, ifa_link) { 393 if (ia->ifa_addr->sa_family != AF_INET6) 394 continue; 395 sin6 = (struct sockaddr_in6 *)ia->ifa_addr; 396 if (!IN6_IS_ADDR_6TO4(&sin6->sin6_addr)) 397 continue; 398 399 bcopy(GET_V4(&sin6->sin6_addr), &in, sizeof(in)); 400 LIST_FOREACH(ia4, INADDR_HASH(in.s_addr), ia_hash) 401 if (ia4->ia_addr.sin_addr.s_addr == in.s_addr) 402 break; 403 if (ia4 == NULL) 404 continue; 405 406 ifa_ref(ia); 407 if_addr_runlock(ifp); 408 return (struct in6_ifaddr *)ia; 409 } 410 if_addr_runlock(ifp); 411 412 return NULL; 413 } 414 415 static int 416 stf_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst, 417 struct route *ro) 418 { 419 struct stf_softc *sc; 420 const struct sockaddr_in6 *dst6; 421 struct route *cached_route; 422 struct in_addr in4; 423 const void *ptr; 424 struct sockaddr_in *dst4; 425 u_int8_t tos; 426 struct ip *ip; 427 struct ip6_hdr *ip6; 428 struct in6_ifaddr *ia6; 429 int error; 430 431 #ifdef MAC 432 error = mac_ifnet_check_transmit(ifp, m); 433 if (error) { 434 m_freem(m); 435 return (error); 436 } 437 #endif 438 439 sc = ifp->if_softc; 440 dst6 = (const struct sockaddr_in6 *)dst; 441 442 /* just in case */ 443 if ((ifp->if_flags & IFF_UP) == 0) { 444 m_freem(m); 445 ifp->if_oerrors++; 446 return ENETDOWN; 447 } 448 449 /* 450 * If we don't have an ip4 address that match my inner ip6 address, 451 * we shouldn't generate output. Without this check, we'll end up 452 * using wrong IPv4 source. 453 */ 454 ia6 = stf_getsrcifa6(ifp); 455 if (ia6 == NULL) { 456 m_freem(m); 457 ifp->if_oerrors++; 458 return ENETDOWN; 459 } 460 461 if (m->m_len < sizeof(*ip6)) { 462 m = m_pullup(m, sizeof(*ip6)); 463 if (!m) { 464 ifa_free(&ia6->ia_ifa); 465 ifp->if_oerrors++; 466 return ENOBUFS; 467 } 468 } 469 ip6 = mtod(m, struct ip6_hdr *); 470 tos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; 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 ifa_free(&ia6->ia_ifa); 483 m_freem(m); 484 ifp->if_oerrors++; 485 return ENETUNREACH; 486 } 487 bcopy(ptr, &in4, sizeof(in4)); 488 489 if (bpf_peers_present(ifp->if_bpf)) { 490 /* 491 * We need to prepend the address family as 492 * a four byte field. Cons up a dummy header 493 * to pacify bpf. This is safe because bpf 494 * will only read from the mbuf (i.e., it won't 495 * try to free it or keep a pointer a to it). 496 */ 497 u_int af = AF_INET6; 498 bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m); 499 } 500 501 M_PREPEND(m, sizeof(struct ip), M_NOWAIT); 502 if (m == NULL) { 503 ifa_free(&ia6->ia_ifa); 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 ifa_free(&ia6->ia_ifa); 514 bcopy(&in4, &ip->ip_dst, sizeof(ip->ip_dst)); 515 ip->ip_p = IPPROTO_IPV6; 516 ip->ip_ttl = ip_stf_ttl; 517 ip->ip_len = htons(m->m_pkthdr.len); 518 if (ifp->if_flags & IFF_LINK1) 519 ip_ecn_ingress(ECN_ALLOWED, &ip->ip_tos, &tos); 520 else 521 ip_ecn_ingress(ECN_NOCARE, &ip->ip_tos, &tos); 522 523 if (!stf_route_cache) { 524 cached_route = NULL; 525 goto sendit; 526 } 527 528 /* 529 * Do we have a cached route? 530 */ 531 mtx_lock(&(sc)->sc_ro_mtx); 532 dst4 = (struct sockaddr_in *)&sc->sc_ro.ro_dst; 533 if (dst4->sin_family != AF_INET || 534 bcmp(&dst4->sin_addr, &ip->ip_dst, sizeof(ip->ip_dst)) != 0) { 535 /* cache route doesn't match */ 536 dst4->sin_family = AF_INET; 537 dst4->sin_len = sizeof(struct sockaddr_in); 538 bcopy(&ip->ip_dst, &dst4->sin_addr, sizeof(dst4->sin_addr)); 539 if (sc->sc_ro.ro_rt) { 540 RTFREE(sc->sc_ro.ro_rt); 541 sc->sc_ro.ro_rt = NULL; 542 } 543 } 544 545 if (sc->sc_ro.ro_rt == NULL) { 546 rtalloc_fib(&sc->sc_ro, sc->sc_fibnum); 547 if (sc->sc_ro.ro_rt == NULL) { 548 m_freem(m); 549 mtx_unlock(&(sc)->sc_ro_mtx); 550 ifp->if_oerrors++; 551 return ENETUNREACH; 552 } 553 } 554 cached_route = &sc->sc_ro; 555 556 sendit: 557 M_SETFIB(m, sc->sc_fibnum); 558 ifp->if_opackets++; 559 error = ip_output(m, NULL, cached_route, 0, NULL, NULL); 560 561 if (cached_route != NULL) 562 mtx_unlock(&(sc)->sc_ro_mtx); 563 return error; 564 } 565 566 static int 567 isrfc1918addr(in) 568 struct in_addr *in; 569 { 570 /* 571 * returns 1 if private address range: 572 * 10.0.0.0/8 172.16.0.0/12 192.168.0.0/16 573 */ 574 if (stf_permit_rfc1918 == 0 && ( 575 (ntohl(in->s_addr) & 0xff000000) >> 24 == 10 || 576 (ntohl(in->s_addr) & 0xfff00000) >> 16 == 172 * 256 + 16 || 577 (ntohl(in->s_addr) & 0xffff0000) >> 16 == 192 * 256 + 168)) 578 return 1; 579 580 return 0; 581 } 582 583 static int 584 stf_checkaddr4(sc, in, inifp) 585 struct stf_softc *sc; 586 struct in_addr *in; 587 struct ifnet *inifp; /* incoming interface */ 588 { 589 struct in_ifaddr *ia4; 590 591 /* 592 * reject packets with the following address: 593 * 224.0.0.0/4 0.0.0.0/8 127.0.0.0/8 255.0.0.0/8 594 */ 595 if (IN_MULTICAST(ntohl(in->s_addr))) 596 return -1; 597 switch ((ntohl(in->s_addr) & 0xff000000) >> 24) { 598 case 0: case 127: case 255: 599 return -1; 600 } 601 602 /* 603 * reject packets with private address range. 604 * (requirement from RFC3056 section 2 1st paragraph) 605 */ 606 if (isrfc1918addr(in)) 607 return -1; 608 609 /* 610 * reject packets with broadcast 611 */ 612 IN_IFADDR_RLOCK(); 613 TAILQ_FOREACH(ia4, &V_in_ifaddrhead, ia_link) { 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 IN_IFADDR_RUNLOCK(); 618 return -1; 619 } 620 } 621 IN_IFADDR_RUNLOCK(); 622 623 /* 624 * perform ingress filter 625 */ 626 if (sc && (STF2IFP(sc)->if_flags & IFF_LINK2) == 0 && inifp) { 627 struct sockaddr_in sin; 628 struct rtentry *rt; 629 630 bzero(&sin, sizeof(sin)); 631 sin.sin_family = AF_INET; 632 sin.sin_len = sizeof(struct sockaddr_in); 633 sin.sin_addr = *in; 634 rt = rtalloc1_fib((struct sockaddr *)&sin, 0, 635 0UL, sc->sc_fibnum); 636 if (!rt || rt->rt_ifp != inifp) { 637 #if 0 638 log(LOG_WARNING, "%s: packet from 0x%x dropped " 639 "due to ingress filter\n", if_name(STF2IFP(sc)), 640 (u_int32_t)ntohl(sin.sin_addr.s_addr)); 641 #endif 642 if (rt) 643 RTFREE_LOCKED(rt); 644 return -1; 645 } 646 RTFREE_LOCKED(rt); 647 } 648 649 return 0; 650 } 651 652 static int 653 stf_checkaddr6(sc, in6, inifp) 654 struct stf_softc *sc; 655 struct in6_addr *in6; 656 struct ifnet *inifp; /* incoming interface */ 657 { 658 /* 659 * check 6to4 addresses 660 */ 661 if (IN6_IS_ADDR_6TO4(in6)) { 662 struct in_addr in4; 663 bcopy(GET_V4(in6), &in4, sizeof(in4)); 664 return stf_checkaddr4(sc, &in4, inifp); 665 } 666 667 /* 668 * reject anything that look suspicious. the test is implemented 669 * in ip6_input too, but we check here as well to 670 * (1) reject bad packets earlier, and 671 * (2) to be safe against future ip6_input change. 672 */ 673 if (IN6_IS_ADDR_V4COMPAT(in6) || IN6_IS_ADDR_V4MAPPED(in6)) 674 return -1; 675 676 return 0; 677 } 678 679 void 680 in_stf_input(m, off) 681 struct mbuf *m; 682 int off; 683 { 684 int proto; 685 struct stf_softc *sc; 686 struct ip *ip; 687 struct ip6_hdr *ip6; 688 u_int8_t otos, itos; 689 struct ifnet *ifp; 690 691 proto = mtod(m, struct ip *)->ip_p; 692 693 if (proto != IPPROTO_IPV6) { 694 m_freem(m); 695 return; 696 } 697 698 ip = mtod(m, struct ip *); 699 700 sc = (struct stf_softc *)encap_getarg(m); 701 702 if (sc == NULL || (STF2IFP(sc)->if_flags & IFF_UP) == 0) { 703 m_freem(m); 704 return; 705 } 706 707 ifp = STF2IFP(sc); 708 709 #ifdef MAC 710 mac_ifnet_create_mbuf(ifp, m); 711 #endif 712 713 /* 714 * perform sanity check against outer src/dst. 715 * for source, perform ingress filter as well. 716 */ 717 if (stf_checkaddr4(sc, &ip->ip_dst, NULL) < 0 || 718 stf_checkaddr4(sc, &ip->ip_src, m->m_pkthdr.rcvif) < 0) { 719 m_freem(m); 720 return; 721 } 722 723 otos = ip->ip_tos; 724 m_adj(m, off); 725 726 if (m->m_len < sizeof(*ip6)) { 727 m = m_pullup(m, sizeof(*ip6)); 728 if (!m) 729 return; 730 } 731 ip6 = mtod(m, struct ip6_hdr *); 732 733 /* 734 * perform sanity check against inner src/dst. 735 * for source, perform ingress filter as well. 736 */ 737 if (stf_checkaddr6(sc, &ip6->ip6_dst, NULL) < 0 || 738 stf_checkaddr6(sc, &ip6->ip6_src, m->m_pkthdr.rcvif) < 0) { 739 m_freem(m); 740 return; 741 } 742 743 itos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; 744 if ((ifp->if_flags & IFF_LINK1) != 0) 745 ip_ecn_egress(ECN_ALLOWED, &otos, &itos); 746 else 747 ip_ecn_egress(ECN_NOCARE, &otos, &itos); 748 ip6->ip6_flow &= ~htonl(0xff << 20); 749 ip6->ip6_flow |= htonl((u_int32_t)itos << 20); 750 751 m->m_pkthdr.rcvif = ifp; 752 753 if (bpf_peers_present(ifp->if_bpf)) { 754 /* 755 * We need to prepend the address family as 756 * a four byte field. Cons up a dummy header 757 * to pacify bpf. This is safe because bpf 758 * will only read from the mbuf (i.e., it won't 759 * try to free it or keep a pointer a to it). 760 */ 761 u_int32_t af = AF_INET6; 762 bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m); 763 } 764 765 /* 766 * Put the packet to the network layer input queue according to the 767 * specified address family. 768 * See net/if_gif.c for possible issues with packet processing 769 * reorder due to extra queueing. 770 */ 771 ifp->if_ipackets++; 772 ifp->if_ibytes += m->m_pkthdr.len; 773 M_SETFIB(m, ifp->if_fib); 774 netisr_dispatch(NETISR_IPV6, m); 775 } 776 777 /* ARGSUSED */ 778 static void 779 stf_rtrequest(cmd, rt, info) 780 int cmd; 781 struct rtentry *rt; 782 struct rt_addrinfo *info; 783 { 784 RT_LOCK_ASSERT(rt); 785 rt->rt_mtu = rt->rt_ifp->if_mtu; 786 } 787 788 static int 789 stf_ioctl(ifp, cmd, data) 790 struct ifnet *ifp; 791 u_long cmd; 792 caddr_t data; 793 { 794 struct ifaddr *ifa; 795 struct ifreq *ifr; 796 struct sockaddr_in6 *sin6; 797 struct in_addr addr; 798 int error, mtu; 799 800 error = 0; 801 switch (cmd) { 802 case SIOCSIFADDR: 803 ifa = (struct ifaddr *)data; 804 if (ifa == NULL || ifa->ifa_addr->sa_family != AF_INET6) { 805 error = EAFNOSUPPORT; 806 break; 807 } 808 sin6 = (struct sockaddr_in6 *)ifa->ifa_addr; 809 if (!IN6_IS_ADDR_6TO4(&sin6->sin6_addr)) { 810 error = EINVAL; 811 break; 812 } 813 bcopy(GET_V4(&sin6->sin6_addr), &addr, sizeof(addr)); 814 if (isrfc1918addr(&addr)) { 815 error = EINVAL; 816 break; 817 } 818 819 ifa->ifa_rtrequest = stf_rtrequest; 820 ifp->if_flags |= IFF_UP; 821 break; 822 823 case SIOCADDMULTI: 824 case SIOCDELMULTI: 825 ifr = (struct ifreq *)data; 826 if (ifr && ifr->ifr_addr.sa_family == AF_INET6) 827 ; 828 else 829 error = EAFNOSUPPORT; 830 break; 831 832 case SIOCGIFMTU: 833 break; 834 835 case SIOCSIFMTU: 836 ifr = (struct ifreq *)data; 837 mtu = ifr->ifr_mtu; 838 /* RFC 4213 3.2 ideal world MTU */ 839 if (mtu < IPV6_MINMTU || mtu > IF_MAXMTU - 20) 840 return (EINVAL); 841 ifp->if_mtu = mtu; 842 break; 843 844 default: 845 error = EINVAL; 846 break; 847 } 848 849 return error; 850 }
Cache object: 9ba6b0f62699d0272026075d24210592
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