1/* $FreeBSD: stable/11/sys/net/if_stf.c 340951 2018-11-26 11:17:12Z eugen $ */ 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 123SYSCTL_DECL(_net_link); 124static SYSCTL_NODE(_net_link, IFT_STF, stf, CTLFLAG_RW, 0, "6to4 Interface"); 125 126static int stf_permit_rfc1918 = 0; 127SYSCTL_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 140struct 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 147static const char stfname[] = "stf"; 148 149static MALLOC_DEFINE(M_STF, stfname, "6to4 Tunnel Interface"); 150static const int ip_stf_ttl = 40; 151 152extern struct domain inetdomain; 153static int in_stf_input(struct mbuf **, int *, int); 154static 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 165static char *stfnames[] = {"stf0", "stf", "6to4", NULL}; 166 167static int stfmodevent(module_t, int, void *); 168static int stf_encapcheck(const struct mbuf *, int, int, void *); 169static int stf_getsrcifa6(struct ifnet *, struct in6_addr *, struct in6_addr *); 170static int stf_output(struct ifnet *, struct mbuf *, const struct sockaddr *, 171 struct route *); 172static int isrfc1918addr(struct in_addr *); 173static int stf_checkaddr4(struct stf_softc *, struct in_addr *, 174 struct ifnet *); 175static int stf_checkaddr6(struct stf_softc *, struct in6_addr *, 176 struct ifnet *); 177static int stf_ioctl(struct ifnet *, u_long, caddr_t); 178 179static int stf_clone_match(struct if_clone *, const char *); 180static int stf_clone_create(struct if_clone *, char *, size_t, caddr_t); 181static int stf_clone_destroy(struct if_clone *, struct ifnet *); 182static struct if_clone *stf_cloner; 183 184static int 185stf_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 197static int 198stf_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 269static int 270stf_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 287static int 288stfmodevent(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 306static moduledata_t stf_mod = { 307 "if_stf", 308 stfmodevent, 309 0 310}; 311 312DECLARE_MODULE(if_stf, stf_mod, SI_SUB_PSEUDO, SI_ORDER_ANY); 313 314static int 315stf_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 /* 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 if (stf_getsrcifa6(STF2IFP(sc), &addr6, &mask6) != 0) 343 return (0); 344 345 /* 346 * check if IPv4 dst matches the IPv4 address derived from the 347 * local 6to4 address. 348 * success on: dst = 10.1.1.1, ia6->ia_addr = 2002:0a01:0101:... 349 */ 350 if (bcmp(GET_V4(&addr6), &ip.ip_dst, sizeof(ip.ip_dst)) != 0) 351 return 0; 352 353 /* 354 * check if IPv4 src matches the IPv4 address derived from the 355 * local 6to4 address masked by prefixmask. 356 * success on: src = 10.1.1.1, ia6->ia_addr = 2002:0a00:.../24 357 * fail on: src = 10.1.1.1, ia6->ia_addr = 2002:0b00:.../24 358 */ 359 bzero(&a, sizeof(a)); 360 bcopy(GET_V4(&addr6), &a, sizeof(a)); 361 bcopy(GET_V4(&mask6), &mask, sizeof(mask)); 362 a.s_addr &= mask.s_addr; 363 b = ip.ip_src; 364 b.s_addr &= mask.s_addr; 365 if (a.s_addr != b.s_addr) 366 return 0; 367 368 /* stf interface makes single side match only */ 369 return 32; 370} 371 372static int 373stf_getsrcifa6(struct ifnet *ifp, struct in6_addr *addr, struct in6_addr *mask) 374{ 375 struct rm_priotracker in_ifa_tracker; 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 IN_IFADDR_RLOCK(&in_ifa_tracker); 392 LIST_FOREACH(ia4, INADDR_HASH(in.s_addr), ia_hash) 393 if (ia4->ia_addr.sin_addr.s_addr == in.s_addr) 394 break; 395 IN_IFADDR_RUNLOCK(&in_ifa_tracker); 396 if (ia4 == NULL) 397 continue; 398 399 ia6 = (struct in6_ifaddr *)ia; 400 401 *addr = sin6->sin6_addr; 402 *mask = ia6->ia_prefixmask.sin6_addr; 403 if_addr_runlock(ifp); 404 return (0); 405 } 406 if_addr_runlock(ifp); 407 408 return (ENOENT); 409} 410 411static int 412stf_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst, 413 struct route *ro) 414{ 415 struct stf_softc *sc; 416 const struct sockaddr_in6 *dst6; 417 struct in_addr in4; 418 const void *ptr; 419 u_int8_t tos; 420 struct ip *ip; 421 struct ip6_hdr *ip6; 422 struct in6_addr addr6, mask6; 423 int error; 424 425#ifdef MAC 426 error = mac_ifnet_check_transmit(ifp, m); 427 if (error) { 428 m_freem(m); 429 return (error); 430 } 431#endif 432 433 sc = ifp->if_softc; 434 dst6 = (const struct sockaddr_in6 *)dst; 435 436 /* just in case */ 437 if ((ifp->if_flags & IFF_UP) == 0) { 438 m_freem(m); 439 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 440 return ENETDOWN; 441 } 442 443 /* 444 * If we don't have an ip4 address that match my inner ip6 address, 445 * we shouldn't generate output. Without this check, we'll end up 446 * using wrong IPv4 source. 447 */ 448 if (stf_getsrcifa6(ifp, &addr6, &mask6) != 0) { 449 m_freem(m); 450 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 451 return ENETDOWN; 452 } 453 454 if (m->m_len < sizeof(*ip6)) { 455 m = m_pullup(m, sizeof(*ip6)); 456 if (!m) { 457 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 458 return ENOBUFS; 459 } 460 } 461 ip6 = mtod(m, struct ip6_hdr *); 462 tos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; 463 464 /* 465 * Pickup the right outer dst addr from the list of candidates. 466 * ip6_dst has priority as it may be able to give us shorter IPv4 hops. 467 */ 468 ptr = NULL; 469 if (IN6_IS_ADDR_6TO4(&ip6->ip6_dst)) 470 ptr = GET_V4(&ip6->ip6_dst); 471 else if (IN6_IS_ADDR_6TO4(&dst6->sin6_addr)) 472 ptr = GET_V4(&dst6->sin6_addr); 473 else { 474 m_freem(m); 475 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 476 return ENETUNREACH; 477 } 478 bcopy(ptr, &in4, sizeof(in4)); 479 480 if (bpf_peers_present(ifp->if_bpf)) { 481 /* 482 * We need to prepend the address family as 483 * a four byte field. Cons up a dummy header 484 * to pacify bpf. This is safe because bpf 485 * will only read from the mbuf (i.e., it won't 486 * try to free it or keep a pointer a to it). 487 */ 488 u_int af = AF_INET6; 489 bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m); 490 } 491 492 M_PREPEND(m, sizeof(struct ip), M_NOWAIT); 493 if (m == NULL) { 494 if_inc_counter(ifp, IFCOUNTER_OERRORS, 1); 495 return ENOBUFS; 496 } 497 ip = mtod(m, struct ip *); 498 499 bzero(ip, sizeof(*ip)); 500 501 bcopy(GET_V4(&addr6), &ip->ip_src, sizeof(ip->ip_src)); 502 bcopy(&in4, &ip->ip_dst, sizeof(ip->ip_dst)); 503 ip->ip_p = IPPROTO_IPV6; 504 ip->ip_ttl = ip_stf_ttl; 505 ip->ip_len = htons(m->m_pkthdr.len); 506 if (ifp->if_flags & IFF_LINK1) 507 ip_ecn_ingress(ECN_ALLOWED, &ip->ip_tos, &tos); 508 else 509 ip_ecn_ingress(ECN_NOCARE, &ip->ip_tos, &tos); 510 511 M_SETFIB(m, sc->sc_fibnum); 512 if_inc_counter(ifp, IFCOUNTER_OPACKETS, 1); 513 error = ip_output(m, NULL, NULL, 0, NULL, NULL); 514 515 return error; 516} 517 518static int 519isrfc1918addr(struct in_addr *in) 520{ 521 /* 522 * returns 1 if private address range: 523 * 10.0.0.0/8 172.16.0.0/12 192.168.0.0/16 524 */ 525 if (stf_permit_rfc1918 == 0 && ( 526 (ntohl(in->s_addr) & 0xff000000) >> 24 == 10 || 527 (ntohl(in->s_addr) & 0xfff00000) >> 16 == 172 * 256 + 16 || 528 (ntohl(in->s_addr) & 0xffff0000) >> 16 == 192 * 256 + 168)) 529 return 1; 530 531 return 0; 532} 533 534static int 535stf_checkaddr4(struct stf_softc *sc, struct in_addr *in, struct ifnet *inifp) 536{ 537 struct rm_priotracker in_ifa_tracker; 538 struct in_ifaddr *ia4; 539 540 /* 541 * reject packets with the following address: 542 * 224.0.0.0/4 0.0.0.0/8 127.0.0.0/8 255.0.0.0/8 543 */ 544 if (IN_MULTICAST(ntohl(in->s_addr))) 545 return -1; 546 switch ((ntohl(in->s_addr) & 0xff000000) >> 24) { 547 case 0: case 127: case 255: 548 return -1; 549 } 550 551 /* 552 * reject packets with private address range. 553 * (requirement from RFC3056 section 2 1st paragraph) 554 */ 555 if (isrfc1918addr(in)) 556 return -1; 557 558 /* 559 * reject packets with broadcast 560 */ 561 IN_IFADDR_RLOCK(&in_ifa_tracker); 562 TAILQ_FOREACH(ia4, &V_in_ifaddrhead, ia_link) { 563 if ((ia4->ia_ifa.ifa_ifp->if_flags & IFF_BROADCAST) == 0) 564 continue; 565 if (in->s_addr == ia4->ia_broadaddr.sin_addr.s_addr) { 566 IN_IFADDR_RUNLOCK(&in_ifa_tracker); 567 return -1; 568 } 569 } 570 IN_IFADDR_RUNLOCK(&in_ifa_tracker); 571 572 /* 573 * perform ingress filter 574 */ 575 if (sc && (STF2IFP(sc)->if_flags & IFF_LINK2) == 0 && inifp) { 576 struct nhop4_basic nh4; 577 578 if (fib4_lookup_nh_basic(sc->sc_fibnum, *in, 0, 0, &nh4) != 0) 579 return (-1); 580 581 if (nh4.nh_ifp != inifp) 582 return (-1); 583 } 584 585 return 0; 586} 587 588static int 589stf_checkaddr6(struct stf_softc *sc, struct in6_addr *in6, struct ifnet *inifp) 590{ 591 /* 592 * check 6to4 addresses 593 */ 594 if (IN6_IS_ADDR_6TO4(in6)) { 595 struct in_addr in4; 596 bcopy(GET_V4(in6), &in4, sizeof(in4)); 597 return stf_checkaddr4(sc, &in4, inifp); 598 } 599 600 /* 601 * reject anything that look suspicious. the test is implemented 602 * in ip6_input too, but we check here as well to 603 * (1) reject bad packets earlier, and 604 * (2) to be safe against future ip6_input change. 605 */ 606 if (IN6_IS_ADDR_V4COMPAT(in6) || IN6_IS_ADDR_V4MAPPED(in6)) 607 return -1; 608 609 return 0; 610} 611 612static int 613in_stf_input(struct mbuf **mp, int *offp, int proto) 614{ 615 struct stf_softc *sc; 616 struct ip *ip; 617 struct ip6_hdr *ip6; 618 struct mbuf *m; 619 u_int8_t otos, itos; 620 struct ifnet *ifp; 621 int off; 622 623 m = *mp; 624 off = *offp; 625 626 if (proto != IPPROTO_IPV6) { 627 m_freem(m); 628 return (IPPROTO_DONE); 629 } 630 631 ip = mtod(m, struct ip *); 632 633 sc = (struct stf_softc *)encap_getarg(m); 634 635 if (sc == NULL || (STF2IFP(sc)->if_flags & IFF_UP) == 0) { 636 m_freem(m); 637 return (IPPROTO_DONE); 638 } 639 640 ifp = STF2IFP(sc); 641 642#ifdef MAC 643 mac_ifnet_create_mbuf(ifp, m); 644#endif 645 646 /* 647 * perform sanity check against outer src/dst. 648 * for source, perform ingress filter as well. 649 */ 650 if (stf_checkaddr4(sc, &ip->ip_dst, NULL) < 0 || 651 stf_checkaddr4(sc, &ip->ip_src, m->m_pkthdr.rcvif) < 0) { 652 m_freem(m); 653 return (IPPROTO_DONE); 654 } 655 656 otos = ip->ip_tos; 657 m_adj(m, off); 658 659 if (m->m_len < sizeof(*ip6)) { 660 m = m_pullup(m, sizeof(*ip6)); 661 if (!m) 662 return (IPPROTO_DONE); 663 } 664 ip6 = mtod(m, struct ip6_hdr *); 665 666 /* 667 * perform sanity check against inner src/dst. 668 * for source, perform ingress filter as well. 669 */ 670 if (stf_checkaddr6(sc, &ip6->ip6_dst, NULL) < 0 || 671 stf_checkaddr6(sc, &ip6->ip6_src, m->m_pkthdr.rcvif) < 0) { 672 m_freem(m); 673 return (IPPROTO_DONE); 674 } 675 676 itos = (ntohl(ip6->ip6_flow) >> 20) & 0xff; 677 if ((ifp->if_flags & IFF_LINK1) != 0) 678 ip_ecn_egress(ECN_ALLOWED, &otos, &itos); 679 else 680 ip_ecn_egress(ECN_NOCARE, &otos, &itos); 681 ip6->ip6_flow &= ~htonl(0xff << 20); 682 ip6->ip6_flow |= htonl((u_int32_t)itos << 20); 683 684 m->m_pkthdr.rcvif = ifp; 685 686 if (bpf_peers_present(ifp->if_bpf)) { 687 /* 688 * We need to prepend the address family as 689 * a four byte field. Cons up a dummy header 690 * to pacify bpf. This is safe because bpf 691 * will only read from the mbuf (i.e., it won't 692 * try to free it or keep a pointer a to it). 693 */ 694 u_int32_t af = AF_INET6; 695 bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m); 696 } 697 698 /* 699 * Put the packet to the network layer input queue according to the 700 * specified address family. 701 * See net/if_gif.c for possible issues with packet processing 702 * reorder due to extra queueing. 703 */ 704 if_inc_counter(ifp, IFCOUNTER_IPACKETS, 1); 705 if_inc_counter(ifp, IFCOUNTER_IBYTES, m->m_pkthdr.len); 706 M_SETFIB(m, ifp->if_fib); 707 netisr_dispatch(NETISR_IPV6, m); 708 return (IPPROTO_DONE); 709} 710 711static int 712stf_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data) 713{ 714 struct ifaddr *ifa; 715 struct ifreq *ifr; 716 struct sockaddr_in6 *sin6; 717 struct in_addr addr; 718 int error, mtu; 719 720 error = 0; 721 switch (cmd) { 722 case SIOCSIFADDR: 723 ifa = (struct ifaddr *)data; 724 if (ifa == NULL || ifa->ifa_addr->sa_family != AF_INET6) { 725 error = EAFNOSUPPORT; 726 break; 727 } 728 sin6 = (struct sockaddr_in6 *)ifa->ifa_addr; 729 if (!IN6_IS_ADDR_6TO4(&sin6->sin6_addr)) { 730 error = EINVAL; 731 break; 732 } 733 bcopy(GET_V4(&sin6->sin6_addr), &addr, sizeof(addr)); 734 if (isrfc1918addr(&addr)) { 735 error = EINVAL; 736 break; 737 } 738 739 ifp->if_flags |= IFF_UP; 740 break; 741 742 case SIOCADDMULTI: 743 case SIOCDELMULTI: 744 ifr = (struct ifreq *)data; 745 if (ifr && ifr->ifr_addr.sa_family == AF_INET6) 746 ; 747 else 748 error = EAFNOSUPPORT; 749 break; 750 751 case SIOCGIFMTU: 752 break; 753 754 case SIOCSIFMTU: 755 ifr = (struct ifreq *)data; 756 mtu = ifr->ifr_mtu; 757 /* RFC 4213 3.2 ideal world MTU */ 758 if (mtu < IPV6_MINMTU || mtu > IF_MAXMTU - 20) 759 return (EINVAL); 760 ifp->if_mtu = mtu; 761 break; 762 763 default: 764 error = EINVAL; 765 break; 766 } 767 768 return error; 769} 770