Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)
[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]
FreeBSD/Linux Kernel Cross Reference
sys/netinet6/ip6_forward.c
Version:
- FREEBSD - FREEBSD-13-STABLE - FREEBSD-13-0 - FREEBSD-12-STABLE - FREEBSD-12-0 - FREEBSD-11-STABLE - FREEBSD-11-0 - FREEBSD-10-STABLE - FREEBSD-10-0 - FREEBSD-9-STABLE - FREEBSD-9-0 - FREEBSD-8-STABLE - FREEBSD-8-0 - FREEBSD-7-STABLE - FREEBSD-7-0 - FREEBSD-6-STABLE - FREEBSD-6-0 - FREEBSD-5-STABLE - FREEBSD-5-0 - FREEBSD-4-STABLE - FREEBSD-3-STABLE - FREEBSD22 - l41 - OPENBSD - linux-2.6 - MK84 - PLAN9 - xnu-8792
SearchContext: - none - 3 - 10
SearchContext: - none - 3 - 10
1 /* $NetBSD: ip6_forward.c,v 1.49.8.2 2009/11/14 10:40:12 sborrill Exp $ */ 2 /* $KAME: ip6_forward.c,v 1.109 2002/09/11 08:10:17 sakane Exp $ */ 3 4 /* 5 * Copyright (C) 1995, 1996, 1997, and 1998 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 #include <sys/cdefs.h> 34 __KERNEL_RCSID(0, "$NetBSD: ip6_forward.c,v 1.49.8.2 2009/11/14 10:40:12 sborrill Exp $"); 35 36 #include "opt_ipsec.h" 37 #include "opt_pfil_hooks.h" 38 39 #include <sys/param.h> 40 #include <sys/systm.h> 41 #include <sys/malloc.h> 42 #include <sys/mbuf.h> 43 #include <sys/domain.h> 44 #include <sys/protosw.h> 45 #include <sys/socket.h> 46 #include <sys/errno.h> 47 #include <sys/time.h> 48 #include <sys/kernel.h> 49 #include <sys/syslog.h> 50 51 #include <net/if.h> 52 #include <net/route.h> 53 54 #include <netinet/in.h> 55 #include <netinet/in_var.h> 56 #include <netinet/ip_var.h> 57 #include <netinet/ip6.h> 58 #include <netinet6/ip6_var.h> 59 #include <netinet6/scope6_var.h> 60 #include <netinet/icmp6.h> 61 #include <netinet6/nd6.h> 62 63 #ifdef IPSEC 64 #include <netinet6/ipsec.h> 65 #include <netkey/key.h> 66 #endif /* IPSEC */ 67 68 #ifdef FAST_IPSEC 69 #include <netipsec/ipsec.h> 70 #include <netipsec/ipsec6.h> 71 #include <netipsec/key.h> 72 #include <netipsec/xform.h> 73 #endif /* FAST_IPSEC */ 74 75 #ifdef PFIL_HOOKS 76 #include <net/pfil.h> 77 #endif 78 79 #include <net/net_osdep.h> 80 81 struct route_in6 ip6_forward_rt; 82 83 #ifdef PFIL_HOOKS 84 extern struct pfil_head inet6_pfil_hook; /* XXX */ 85 #endif 86 87 /* 88 * Forward a packet. If some error occurs return the sender 89 * an icmp packet. Note we can't always generate a meaningful 90 * icmp message because icmp doesn't have a large enough repertoire 91 * of codes and types. 92 * 93 * If not forwarding, just drop the packet. This could be confusing 94 * if ipforwarding was zero but some routing protocol was advancing 95 * us as a gateway to somewhere. However, we must let the routing 96 * protocol deal with that. 97 * 98 */ 99 100 void 101 ip6_forward(m, srcrt) 102 struct mbuf *m; 103 int srcrt; 104 { 105 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 106 struct sockaddr_in6 *dst; 107 struct rtentry *rt; 108 int error = 0, type = 0, code = 0; 109 struct mbuf *mcopy = NULL; 110 struct ifnet *origifp; /* maybe unnecessary */ 111 u_int32_t inzone, outzone; 112 struct in6_addr src_in6, dst_in6; 113 #ifdef IPSEC 114 struct secpolicy *sp = NULL; 115 int ipsecrt = 0; 116 #endif 117 #ifdef FAST_IPSEC 118 struct secpolicy *sp = NULL; 119 int needipsec = 0; 120 int s; 121 #endif 122 123 /* 124 * Clear any in-bound checksum flags for this packet. 125 */ 126 m->m_pkthdr.csum_flags = 0; 127 128 #ifdef IPSEC 129 /* 130 * Check AH/ESP integrity. 131 */ 132 /* 133 * Don't increment ip6s_cantforward because this is the check 134 * before forwarding packet actually. 135 */ 136 if (ipsec6_in_reject(m, NULL)) { 137 ipsec6stat.in_polvio++; 138 m_freem(m); 139 return; 140 } 141 #endif /* IPSEC */ 142 143 /* 144 * Do not forward packets to multicast destination (should be handled 145 * by ip6_mforward(). 146 * Do not forward packets with unspecified source. It was discussed 147 * in July 2000, on ipngwg mailing list. 148 */ 149 if ((m->m_flags & (M_BCAST|M_MCAST)) != 0 || 150 IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) || 151 IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src)) { 152 ip6stat.ip6s_cantforward++; 153 /* XXX in6_ifstat_inc(rt->rt_ifp, ifs6_in_discard) */ 154 if (ip6_log_time + ip6_log_interval < time_second) { 155 ip6_log_time = time_second; 156 log(LOG_DEBUG, 157 "cannot forward " 158 "from %s to %s nxt %d received on %s\n", 159 ip6_sprintf(&ip6->ip6_src), 160 ip6_sprintf(&ip6->ip6_dst), 161 ip6->ip6_nxt, 162 if_name(m->m_pkthdr.rcvif)); 163 } 164 m_freem(m); 165 return; 166 } 167 168 if (ip6->ip6_hlim <= IPV6_HLIMDEC) { 169 /* XXX in6_ifstat_inc(rt->rt_ifp, ifs6_in_discard) */ 170 icmp6_error(m, ICMP6_TIME_EXCEEDED, 171 ICMP6_TIME_EXCEED_TRANSIT, 0); 172 return; 173 } 174 ip6->ip6_hlim -= IPV6_HLIMDEC; 175 176 /* 177 * Save at most ICMPV6_PLD_MAXLEN (= the min IPv6 MTU - 178 * size of IPv6 + ICMPv6 headers) bytes of the packet in case 179 * we need to generate an ICMP6 message to the src. 180 * Thanks to M_EXT, in most cases copy will not occur. 181 * 182 * It is important to save it before IPsec processing as IPsec 183 * processing may modify the mbuf. 184 */ 185 mcopy = m_copy(m, 0, imin(m->m_pkthdr.len, ICMPV6_PLD_MAXLEN)); 186 187 #ifdef IPSEC 188 /* get a security policy for this packet */ 189 sp = ipsec6_getpolicybyaddr(m, IPSEC_DIR_OUTBOUND, 190 IP_FORWARDING, &error); 191 if (sp == NULL) { 192 ipsec6stat.out_inval++; 193 ip6stat.ip6s_cantforward++; 194 if (mcopy) { 195 #if 0 196 /* XXX: what icmp ? */ 197 #else 198 m_freem(mcopy); 199 #endif 200 } 201 m_freem(m); 202 return; 203 } 204 205 error = 0; 206 207 /* check policy */ 208 switch (sp->policy) { 209 case IPSEC_POLICY_DISCARD: 210 /* 211 * This packet is just discarded. 212 */ 213 ipsec6stat.out_polvio++; 214 ip6stat.ip6s_cantforward++; 215 key_freesp(sp); 216 if (mcopy) { 217 #if 0 218 /* XXX: what icmp ? */ 219 #else 220 m_freem(mcopy); 221 #endif 222 } 223 m_freem(m); 224 return; 225 226 case IPSEC_POLICY_BYPASS: 227 case IPSEC_POLICY_NONE: 228 /* no need to do IPsec. */ 229 key_freesp(sp); 230 goto skip_ipsec; 231 232 case IPSEC_POLICY_IPSEC: 233 if (sp->req == NULL) { 234 /* XXX should be panic ? */ 235 printf("ip6_forward: No IPsec request specified.\n"); 236 ip6stat.ip6s_cantforward++; 237 key_freesp(sp); 238 if (mcopy) { 239 #if 0 240 /* XXX: what icmp ? */ 241 #else 242 m_freem(mcopy); 243 #endif 244 } 245 m_freem(m); 246 return; 247 } 248 /* do IPsec */ 249 break; 250 251 case IPSEC_POLICY_ENTRUST: 252 default: 253 /* should be panic ?? */ 254 printf("ip6_forward: Invalid policy found. %d\n", sp->policy); 255 key_freesp(sp); 256 goto skip_ipsec; 257 } 258 259 { 260 struct ipsecrequest *isr = NULL; 261 struct ipsec_output_state state; 262 263 /* 264 * when the kernel forwards a packet, it is not proper to apply 265 * IPsec transport mode to the packet is not proper. this check 266 * avoid from this. 267 * at present, if there is even a transport mode SA request in the 268 * security policy, the kernel does not apply IPsec to the packet. 269 * this check is not enough because the following case is valid. 270 * ipsec esp/tunnel/xxx-xxx/require esp/transport//require; 271 */ 272 for (isr = sp->req; isr; isr = isr->next) { 273 if (isr->saidx.mode == IPSEC_MODE_ANY) 274 goto doipsectunnel; 275 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 276 goto doipsectunnel; 277 } 278 279 /* 280 * if there's no need for tunnel mode IPsec, skip. 281 */ 282 if (!isr) 283 goto skip_ipsec; 284 285 doipsectunnel: 286 /* 287 * All the extension headers will become inaccessible 288 * (since they can be encrypted). 289 * Don't panic, we need no more updates to extension headers 290 * on inner IPv6 packet (since they are now encapsulated). 291 * 292 * IPv6 [ESP|AH] IPv6 [extension headers] payload 293 */ 294 bzero(&state, sizeof(state)); 295 state.m = m; 296 state.ro = NULL; /* update at ipsec6_output_tunnel() */ 297 state.dst = NULL; /* update at ipsec6_output_tunnel() */ 298 299 error = ipsec6_output_tunnel(&state, sp, 0); 300 301 m = state.m; 302 key_freesp(sp); 303 304 if (error) { 305 /* mbuf is already reclaimed in ipsec6_output_tunnel. */ 306 switch (error) { 307 case EHOSTUNREACH: 308 case ENETUNREACH: 309 case EMSGSIZE: 310 case ENOBUFS: 311 case ENOMEM: 312 break; 313 default: 314 printf("ip6_forward (ipsec): error code %d\n", error); 315 /* FALLTHROUGH */ 316 case ENOENT: 317 /* don't show these error codes to the user */ 318 break; 319 } 320 ip6stat.ip6s_cantforward++; 321 if (mcopy) { 322 #if 0 323 /* XXX: what icmp ? */ 324 #else 325 m_freem(mcopy); 326 #endif 327 } 328 m_freem(m); 329 return; 330 } 331 332 if (ip6 != mtod(m, struct ip6_hdr *)) { 333 /* 334 * now tunnel mode headers are added. we are originating 335 * packet instead of forwarding the packet. 336 */ 337 ip6_output(m, NULL, NULL, IPV6_FORWARDING/*XXX*/, NULL, NULL, 338 NULL); 339 goto freecopy; 340 } 341 342 /* adjust pointer */ 343 rt = state.ro ? state.ro->ro_rt : NULL; 344 dst = (struct sockaddr_in6 *)state.dst; 345 if (dst != NULL && rt != NULL) { 346 ipsecrt = 1; 347 goto skip_routing; 348 } 349 } 350 skip_ipsec: 351 #endif /* IPSEC */ 352 #ifdef FAST_IPSEC 353 /* Check the security policy (SP) for the packet */ 354 355 sp = ipsec6_check_policy(m,NULL,0,&needipsec,&error); 356 if (error != 0) { 357 /* 358 * Hack: -EINVAL is used to signal that a packet 359 * should be silently discarded. This is typically 360 * because we asked key management for an SA and 361 * it was delayed (e.g. kicked up to IKE). 362 */ 363 if (error == -EINVAL) 364 error = 0; 365 goto freecopy; 366 } 367 #endif /* FAST_IPSEC */ 368 369 370 371 dst = &ip6_forward_rt.ro_dst; 372 if (!srcrt) { 373 /* 374 * ip6_forward_rt.ro_dst.sin6_addr is equal to ip6->ip6_dst 375 */ 376 if (ip6_forward_rt.ro_rt == 0 || 377 (ip6_forward_rt.ro_rt->rt_flags & RTF_UP) == 0) { 378 if (ip6_forward_rt.ro_rt) { 379 RTFREE(ip6_forward_rt.ro_rt); 380 ip6_forward_rt.ro_rt = 0; 381 } 382 /* this probably fails but give it a try again */ 383 rtalloc((struct route *)&ip6_forward_rt); 384 } 385 386 if (ip6_forward_rt.ro_rt == 0) { 387 ip6stat.ip6s_noroute++; 388 /* XXX in6_ifstat_inc(rt->rt_ifp, ifs6_in_noroute) */ 389 if (mcopy) { 390 icmp6_error(mcopy, ICMP6_DST_UNREACH, 391 ICMP6_DST_UNREACH_NOROUTE, 0); 392 } 393 m_freem(m); 394 return; 395 } 396 } else if ((rt = ip6_forward_rt.ro_rt) == 0 || 397 !IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, &dst->sin6_addr)) { 398 if (ip6_forward_rt.ro_rt) { 399 RTFREE(ip6_forward_rt.ro_rt); 400 ip6_forward_rt.ro_rt = 0; 401 } 402 bzero(dst, sizeof(*dst)); 403 dst->sin6_len = sizeof(struct sockaddr_in6); 404 dst->sin6_family = AF_INET6; 405 dst->sin6_addr = ip6->ip6_dst; 406 407 rtalloc((struct route *)&ip6_forward_rt); 408 if (ip6_forward_rt.ro_rt == 0) { 409 ip6stat.ip6s_noroute++; 410 /* XXX in6_ifstat_inc(rt->rt_ifp, ifs6_in_noroute) */ 411 if (mcopy) { 412 icmp6_error(mcopy, ICMP6_DST_UNREACH, 413 ICMP6_DST_UNREACH_NOROUTE, 0); 414 } 415 m_freem(m); 416 return; 417 } 418 } 419 rt = ip6_forward_rt.ro_rt; 420 #ifdef IPSEC 421 skip_routing:; 422 #endif /* IPSEC */ 423 424 /* 425 * Source scope check: if a packet can't be delivered to its 426 * destination for the reason that the destination is beyond the scope 427 * of the source address, discard the packet and return an icmp6 428 * destination unreachable error with Code 2 (beyond scope of source 429 * address). We use a local copy of ip6_src, since in6_setscope() 430 * will possibly modify its first argument. 431 * [draft-ietf-ipngwg-icmp-v3-07, Section 3.1] 432 */ 433 src_in6 = ip6->ip6_src; 434 if (in6_setscope(&src_in6, rt->rt_ifp, &outzone)) { 435 /* XXX: this should not happen */ 436 ip6stat.ip6s_cantforward++; 437 ip6stat.ip6s_badscope++; 438 m_freem(m); 439 return; 440 } 441 if (in6_setscope(&src_in6, m->m_pkthdr.rcvif, &inzone)) { 442 ip6stat.ip6s_cantforward++; 443 ip6stat.ip6s_badscope++; 444 m_freem(m); 445 return; 446 } 447 if (inzone != outzone 448 #ifdef IPSEC 449 && !ipsecrt 450 #endif 451 ) { 452 ip6stat.ip6s_cantforward++; 453 ip6stat.ip6s_badscope++; 454 in6_ifstat_inc(rt->rt_ifp, ifs6_in_discard); 455 456 if (ip6_log_time + ip6_log_interval < time_second) { 457 ip6_log_time = time_second; 458 log(LOG_DEBUG, 459 "cannot forward " 460 "src %s, dst %s, nxt %d, rcvif %s, outif %s\n", 461 ip6_sprintf(&ip6->ip6_src), 462 ip6_sprintf(&ip6->ip6_dst), 463 ip6->ip6_nxt, 464 if_name(m->m_pkthdr.rcvif), if_name(rt->rt_ifp)); 465 } 466 if (mcopy) 467 icmp6_error(mcopy, ICMP6_DST_UNREACH, 468 ICMP6_DST_UNREACH_BEYONDSCOPE, 0); 469 m_freem(m); 470 return; 471 } 472 #ifdef FAST_IPSEC 473 /* 474 * If we need to encapsulate the packet, do it here 475 * ipsec6_proces_packet will send the packet using ip6_output 476 */ 477 if (needipsec) { 478 s = splsoftnet(); 479 error = ipsec6_process_packet(m,sp->req); 480 splx(s); 481 if (mcopy) 482 goto freecopy; 483 } 484 #endif 485 486 487 488 /* 489 * Destination scope check: if a packet is going to break the scope 490 * zone of packet's destination address, discard it. This case should 491 * usually be prevented by appropriately-configured routing table, but 492 * we need an explicit check because we may mistakenly forward the 493 * packet to a different zone by (e.g.) a default route. 494 */ 495 dst_in6 = ip6->ip6_dst; 496 if (in6_setscope(&dst_in6, m->m_pkthdr.rcvif, &inzone) != 0 || 497 in6_setscope(&dst_in6, rt->rt_ifp, &outzone) != 0 || 498 inzone != outzone) { 499 ip6stat.ip6s_cantforward++; 500 ip6stat.ip6s_badscope++; 501 m_freem(m); 502 return; 503 } 504 505 if (m->m_pkthdr.len > IN6_LINKMTU(rt->rt_ifp)) { 506 in6_ifstat_inc(rt->rt_ifp, ifs6_in_toobig); 507 if (mcopy) { 508 u_long mtu; 509 #ifdef IPSEC 510 struct secpolicy *xsp; 511 int ipsecerror; 512 size_t ipsechdrsiz; 513 #endif 514 515 mtu = IN6_LINKMTU(rt->rt_ifp); 516 #ifdef IPSEC 517 /* 518 * When we do IPsec tunnel ingress, we need to play 519 * with the link value (decrement IPsec header size 520 * from mtu value). The code is much simpler than v4 521 * case, as we have the outgoing interface for 522 * encapsulated packet as "rt->rt_ifp". 523 */ 524 xsp = ipsec6_getpolicybyaddr(mcopy, IPSEC_DIR_OUTBOUND, 525 IP_FORWARDING, &ipsecerror); 526 if (xsp) { 527 ipsechdrsiz = ipsec6_hdrsiz(mcopy, 528 IPSEC_DIR_OUTBOUND, NULL); 529 if (ipsechdrsiz < mtu) 530 mtu -= ipsechdrsiz; 531 } 532 533 /* 534 * if mtu becomes less than minimum MTU, 535 * tell minimum MTU (and I'll need to fragment it). 536 */ 537 if (mtu < IPV6_MMTU) 538 mtu = IPV6_MMTU; 539 #endif 540 icmp6_error(mcopy, ICMP6_PACKET_TOO_BIG, 0, mtu); 541 } 542 m_freem(m); 543 return; 544 } 545 546 if (rt->rt_flags & RTF_GATEWAY) 547 dst = (struct sockaddr_in6 *)rt->rt_gateway; 548 549 /* 550 * If we are to forward the packet using the same interface 551 * as one we got the packet from, perhaps we should send a redirect 552 * to sender to shortcut a hop. 553 * Only send redirect if source is sending directly to us, 554 * and if packet was not source routed (or has any options). 555 * Also, don't send redirect if forwarding using a route 556 * modified by a redirect. 557 */ 558 if (rt->rt_ifp == m->m_pkthdr.rcvif && !srcrt && ip6_sendredirects && 559 #ifdef IPSEC 560 !ipsecrt && 561 #endif 562 (rt->rt_flags & (RTF_DYNAMIC|RTF_MODIFIED)) == 0) { 563 if ((rt->rt_ifp->if_flags & IFF_POINTOPOINT) && 564 nd6_is_addr_neighbor((struct sockaddr_in6 *)&ip6_forward_rt.ro_dst, rt->rt_ifp)) { 565 /* 566 * If the incoming interface is equal to the outgoing 567 * one, the link attached to the interface is 568 * point-to-point, and the IPv6 destination is 569 * regarded as on-link on the link, then it will be 570 * highly probable that the destination address does 571 * not exist on the link and that the packet is going 572 * to loop. Thus, we immediately drop the packet and 573 * send an ICMPv6 error message. 574 * For other routing loops, we dare to let the packet 575 * go to the loop, so that a remote diagnosing host 576 * can detect the loop by traceroute. 577 * type/code is based on suggestion by Rich Draves. 578 * not sure if it is the best pick. 579 */ 580 icmp6_error(mcopy, ICMP6_DST_UNREACH, 581 ICMP6_DST_UNREACH_ADDR, 0); 582 m_freem(m); 583 return; 584 } 585 type = ND_REDIRECT; 586 } 587 588 /* 589 * Fake scoped addresses. Note that even link-local source or 590 * destinaion can appear, if the originating node just sends the 591 * packet to us (without address resolution for the destination). 592 * Since both icmp6_error and icmp6_redirect_output fill the embedded 593 * link identifiers, we can do this stuff after making a copy for 594 * returning an error. 595 */ 596 if ((rt->rt_ifp->if_flags & IFF_LOOPBACK) != 0) { 597 /* 598 * See corresponding comments in ip6_output. 599 * XXX: but is it possible that ip6_forward() sends a packet 600 * to a loopback interface? I don't think so, and thus 601 * I bark here. (jinmei@kame.net) 602 * XXX: it is common to route invalid packets to loopback. 603 * also, the codepath will be visited on use of ::1 in 604 * rthdr. (itojun) 605 */ 606 #if 1 607 if (0) 608 #else 609 if ((rt->rt_flags & (RTF_BLACKHOLE|RTF_REJECT)) == 0) 610 #endif 611 { 612 printf("ip6_forward: outgoing interface is loopback. " 613 "src %s, dst %s, nxt %d, rcvif %s, outif %s\n", 614 ip6_sprintf(&ip6->ip6_src), 615 ip6_sprintf(&ip6->ip6_dst), 616 ip6->ip6_nxt, if_name(m->m_pkthdr.rcvif), 617 if_name(rt->rt_ifp)); 618 } 619 620 /* we can just use rcvif in forwarding. */ 621 origifp = m->m_pkthdr.rcvif; 622 } 623 else 624 origifp = rt->rt_ifp; 625 /* 626 * clear embedded scope identifiers if necessary. 627 * in6_clearscope will touch the addresses only when necessary. 628 */ 629 in6_clearscope(&ip6->ip6_src); 630 in6_clearscope(&ip6->ip6_dst); 631 632 #ifdef PFIL_HOOKS 633 /* 634 * Run through list of hooks for output packets. 635 */ 636 if ((error = pfil_run_hooks(&inet6_pfil_hook, &m, rt->rt_ifp, 637 PFIL_OUT)) != 0) 638 goto senderr; 639 if (m == NULL) 640 goto freecopy; 641 ip6 = mtod(m, struct ip6_hdr *); 642 #endif /* PFIL_HOOKS */ 643 644 error = nd6_output(rt->rt_ifp, origifp, m, dst, rt); 645 if (error) { 646 in6_ifstat_inc(rt->rt_ifp, ifs6_out_discard); 647 ip6stat.ip6s_cantforward++; 648 } else { 649 ip6stat.ip6s_forward++; 650 in6_ifstat_inc(rt->rt_ifp, ifs6_out_forward); 651 if (type) 652 ip6stat.ip6s_redirectsent++; 653 else { 654 if (mcopy) 655 goto freecopy; 656 } 657 } 658 659 #ifdef PFIL_HOOKS 660 senderr: 661 #endif 662 if (mcopy == NULL) 663 return; 664 switch (error) { 665 case 0: 666 if (type == ND_REDIRECT) { 667 icmp6_redirect_output(mcopy, rt); 668 return; 669 } 670 goto freecopy; 671 672 case EMSGSIZE: 673 /* xxx MTU is constant in PPP? */ 674 goto freecopy; 675 676 case ENOBUFS: 677 /* Tell source to slow down like source quench in IP? */ 678 goto freecopy; 679 680 case ENETUNREACH: /* shouldn't happen, checked above */ 681 case EHOSTUNREACH: 682 case ENETDOWN: 683 case EHOSTDOWN: 684 default: 685 type = ICMP6_DST_UNREACH; 686 code = ICMP6_DST_UNREACH_ADDR; 687 break; 688 } 689 icmp6_error(mcopy, type, code, 0); 690 return; 691 692 freecopy: 693 m_freem(mcopy); 694 return; 695 }
Cache object: 8a0ed41c15b96870752ded10b5691fb6
[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]