Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)
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sys/netinet6/ip6_forward.c
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1 /*- 2 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of the project nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * $KAME: ip6_forward.c,v 1.69 2001/05/17 03:48:30 itojun Exp $ 30 */ 31 32 #include <sys/cdefs.h> 33 __FBSDID("$FreeBSD: releng/6.4/sys/netinet6/ip6_forward.c 182649 2008-09-01 22:57:56Z obrien $"); 34 35 #include "opt_ip6fw.h" 36 #include "opt_inet.h" 37 #include "opt_inet6.h" 38 #include "opt_ipsec.h" 39 #include "opt_ipstealth.h" 40 41 #include <sys/param.h> 42 #include <sys/systm.h> 43 #include <sys/malloc.h> 44 #include <sys/mbuf.h> 45 #include <sys/domain.h> 46 #include <sys/protosw.h> 47 #include <sys/socket.h> 48 #include <sys/errno.h> 49 #include <sys/time.h> 50 #include <sys/kernel.h> 51 #include <sys/syslog.h> 52 53 #include <net/if.h> 54 #include <net/route.h> 55 #include <net/pfil.h> 56 57 #include <netinet/in.h> 58 #include <netinet/in_var.h> 59 #include <netinet/in_systm.h> 60 #include <netinet/ip.h> 61 #include <netinet/ip_var.h> 62 #include <netinet6/in6_var.h> 63 #include <netinet/ip6.h> 64 #include <netinet6/ip6_var.h> 65 #include <netinet6/scope6_var.h> 66 #include <netinet/icmp6.h> 67 #include <netinet6/nd6.h> 68 69 #include <netinet/in_pcb.h> 70 71 #ifdef IPSEC 72 #include <netinet6/ipsec.h> 73 #ifdef INET6 74 #include <netinet6/ipsec6.h> 75 #endif 76 #include <netkey/key.h> 77 #endif /* IPSEC */ 78 79 #ifdef FAST_IPSEC 80 #include <netipsec/ipsec.h> 81 #include <netipsec/ipsec6.h> 82 #include <netipsec/key.h> 83 #define IPSEC 84 #endif /* FAST_IPSEC */ 85 86 #include <netinet6/ip6_fw.h> 87 88 #include <net/net_osdep.h> 89 90 #include <netinet6/ip6protosw.h> 91 92 struct route_in6 ip6_forward_rt; 93 94 /* 95 * Forward a packet. If some error occurs return the sender 96 * an icmp packet. Note we can't always generate a meaningful 97 * icmp message because icmp doesn't have a large enough repertoire 98 * of codes and types. 99 * 100 * If not forwarding, just drop the packet. This could be confusing 101 * if ipforwarding was zero but some routing protocol was advancing 102 * us as a gateway to somewhere. However, we must let the routing 103 * protocol deal with that. 104 * 105 */ 106 107 void 108 ip6_forward(m, srcrt) 109 struct mbuf *m; 110 int srcrt; 111 { 112 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 113 struct sockaddr_in6 *dst = NULL; 114 struct rtentry *rt = NULL; 115 int error, type = 0, code = 0; 116 struct mbuf *mcopy = NULL; 117 struct ifnet *origifp; /* maybe unnecessary */ 118 u_int32_t inzone, outzone; 119 struct in6_addr src_in6, dst_in6; 120 #ifdef IPSEC 121 struct secpolicy *sp = NULL; 122 int ipsecrt = 0; 123 #endif 124 125 #ifdef IPSEC 126 /* 127 * Check AH/ESP integrity. 128 */ 129 /* 130 * Don't increment ip6s_cantforward because this is the check 131 * before forwarding packet actually. 132 */ 133 if (ipsec6_in_reject(m, NULL)) { 134 #if !defined(FAST_IPSEC) 135 ipsec6stat.in_polvio++; 136 #endif 137 m_freem(m); 138 return; 139 } 140 #endif /* IPSEC */ 141 142 /* 143 * Do not forward packets to multicast destination (should be handled 144 * by ip6_mforward(). 145 * Do not forward packets with unspecified source. It was discussed 146 * in July 2000, on the ipngwg mailing list. 147 */ 148 if ((m->m_flags & (M_BCAST|M_MCAST)) != 0 || 149 IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) || 150 IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src)) { 151 ip6stat.ip6s_cantforward++; 152 /* XXX in6_ifstat_inc(rt->rt_ifp, ifs6_in_discard) */ 153 if (ip6_log_time + ip6_log_interval < time_second) { 154 ip6_log_time = time_second; 155 log(LOG_DEBUG, 156 "cannot forward " 157 "from %s to %s nxt %d received on %s\n", 158 ip6_sprintf(&ip6->ip6_src), 159 ip6_sprintf(&ip6->ip6_dst), 160 ip6->ip6_nxt, 161 if_name(m->m_pkthdr.rcvif)); 162 } 163 m_freem(m); 164 return; 165 } 166 167 #ifdef IPSTEALTH 168 if (!ip6stealth) { 169 #endif 170 if (ip6->ip6_hlim <= IPV6_HLIMDEC) { 171 /* XXX in6_ifstat_inc(rt->rt_ifp, ifs6_in_discard) */ 172 icmp6_error(m, ICMP6_TIME_EXCEEDED, 173 ICMP6_TIME_EXCEED_TRANSIT, 0); 174 return; 175 } 176 ip6->ip6_hlim -= IPV6_HLIMDEC; 177 178 #ifdef IPSTEALTH 179 } 180 #endif 181 182 /* 183 * Save at most ICMPV6_PLD_MAXLEN (= the min IPv6 MTU - 184 * size of IPv6 + ICMPv6 headers) bytes of the packet in case 185 * we need to generate an ICMP6 message to the src. 186 * Thanks to M_EXT, in most cases copy will not occur. 187 * 188 * It is important to save it before IPsec processing as IPsec 189 * processing may modify the mbuf. 190 */ 191 mcopy = m_copy(m, 0, imin(m->m_pkthdr.len, ICMPV6_PLD_MAXLEN)); 192 193 #ifdef IPSEC 194 /* get a security policy for this packet */ 195 sp = ipsec6_getpolicybyaddr(m, IPSEC_DIR_OUTBOUND, 196 IP_FORWARDING, &error); 197 if (sp == NULL) { 198 ipsec6stat.out_inval++; 199 ip6stat.ip6s_cantforward++; 200 if (mcopy) { 201 #if 0 202 /* XXX: what icmp ? */ 203 #else 204 m_freem(mcopy); 205 #endif 206 } 207 m_freem(m); 208 return; 209 } 210 211 error = 0; 212 213 /* check policy */ 214 switch (sp->policy) { 215 case IPSEC_POLICY_DISCARD: 216 /* 217 * This packet is just discarded. 218 */ 219 ipsec6stat.out_polvio++; 220 ip6stat.ip6s_cantforward++; 221 key_freesp(sp); 222 if (mcopy) { 223 #if 0 224 /* XXX: what icmp ? */ 225 #else 226 m_freem(mcopy); 227 #endif 228 } 229 m_freem(m); 230 return; 231 232 case IPSEC_POLICY_BYPASS: 233 case IPSEC_POLICY_NONE: 234 /* no need to do IPsec. */ 235 key_freesp(sp); 236 goto skip_ipsec; 237 238 case IPSEC_POLICY_IPSEC: 239 if (sp->req == NULL) { 240 /* XXX should be panic ? */ 241 printf("ip6_forward: No IPsec request specified.\n"); 242 ip6stat.ip6s_cantforward++; 243 key_freesp(sp); 244 if (mcopy) { 245 #if 0 246 /* XXX: what icmp ? */ 247 #else 248 m_freem(mcopy); 249 #endif 250 } 251 m_freem(m); 252 return; 253 } 254 /* do IPsec */ 255 break; 256 257 case IPSEC_POLICY_ENTRUST: 258 default: 259 /* should be panic ?? */ 260 printf("ip6_forward: Invalid policy found. %d\n", sp->policy); 261 key_freesp(sp); 262 goto skip_ipsec; 263 } 264 265 { 266 struct ipsecrequest *isr = NULL; 267 struct ipsec_output_state state; 268 269 /* 270 * when the kernel forwards a packet, it is not proper to apply 271 * IPsec transport mode to the packet is not proper. this check 272 * avoid from this. 273 * at present, if there is even a transport mode SA request in the 274 * security policy, the kernel does not apply IPsec to the packet. 275 * this check is not enough because the following case is valid. 276 * ipsec esp/tunnel/xxx-xxx/require esp/transport//require; 277 */ 278 for (isr = sp->req; isr; isr = isr->next) { 279 if (isr->saidx.mode == IPSEC_MODE_ANY) 280 goto doipsectunnel; 281 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) 282 goto doipsectunnel; 283 } 284 285 /* 286 * if there's no need for tunnel mode IPsec, skip. 287 */ 288 if (!isr) 289 goto skip_ipsec; 290 291 doipsectunnel: 292 /* 293 * All the extension headers will become inaccessible 294 * (since they can be encrypted). 295 * Don't panic, we need no more updates to extension headers 296 * on inner IPv6 packet (since they are now encapsulated). 297 * 298 * IPv6 [ESP|AH] IPv6 [extension headers] payload 299 */ 300 bzero(&state, sizeof(state)); 301 state.m = m; 302 state.ro = NULL; /* update at ipsec6_output_tunnel() */ 303 state.dst = NULL; /* update at ipsec6_output_tunnel() */ 304 305 error = ipsec6_output_tunnel(&state, sp, 0); 306 307 m = state.m; 308 key_freesp(sp); 309 310 if (error) { 311 /* mbuf is already reclaimed in ipsec6_output_tunnel. */ 312 switch (error) { 313 case EHOSTUNREACH: 314 case ENETUNREACH: 315 case EMSGSIZE: 316 case ENOBUFS: 317 case ENOMEM: 318 break; 319 default: 320 printf("ip6_output (ipsec): error code %d\n", error); 321 /* FALLTHROUGH */ 322 case ENOENT: 323 /* don't show these error codes to the user */ 324 break; 325 } 326 ip6stat.ip6s_cantforward++; 327 if (mcopy) { 328 #if 0 329 /* XXX: what icmp ? */ 330 #else 331 m_freem(mcopy); 332 #endif 333 } 334 m_freem(m); 335 return; 336 } 337 338 if (ip6 != mtod(m, struct ip6_hdr *)) { 339 /* 340 * now tunnel mode headers are added. we are originating 341 * packet instead of forwarding the packet. 342 */ 343 ip6_output(m, NULL, NULL, IPV6_FORWARDING/*XXX*/, NULL, NULL, 344 NULL); 345 goto freecopy; 346 } 347 348 /* adjust pointer */ 349 dst = (struct sockaddr_in6 *)state.dst; 350 rt = state.ro ? state.ro->ro_rt : NULL; 351 if (dst != NULL && rt != NULL) 352 ipsecrt = 1; 353 } 354 skip_ipsec: 355 #endif /* IPSEC */ 356 357 #ifdef IPSEC 358 if (ipsecrt) 359 goto skip_routing; 360 #endif 361 362 dst = (struct sockaddr_in6 *)&ip6_forward_rt.ro_dst; 363 if (!srcrt) { 364 /* ip6_forward_rt.ro_dst.sin6_addr is equal to ip6->ip6_dst */ 365 if (ip6_forward_rt.ro_rt == 0 || 366 (ip6_forward_rt.ro_rt->rt_flags & RTF_UP) == 0) { 367 if (ip6_forward_rt.ro_rt) { 368 RTFREE(ip6_forward_rt.ro_rt); 369 ip6_forward_rt.ro_rt = 0; 370 } 371 372 /* this probably fails but give it a try again */ 373 rtalloc((struct route *)&ip6_forward_rt); 374 } 375 376 if (ip6_forward_rt.ro_rt == 0) { 377 ip6stat.ip6s_noroute++; 378 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_noroute); 379 if (mcopy) { 380 icmp6_error(mcopy, ICMP6_DST_UNREACH, 381 ICMP6_DST_UNREACH_NOROUTE, 0); 382 } 383 m_freem(m); 384 return; 385 } 386 } else if ((rt = ip6_forward_rt.ro_rt) == 0 || 387 !IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, &dst->sin6_addr)) { 388 if (ip6_forward_rt.ro_rt) { 389 RTFREE(ip6_forward_rt.ro_rt); 390 ip6_forward_rt.ro_rt = 0; 391 } 392 bzero(dst, sizeof(*dst)); 393 dst->sin6_len = sizeof(struct sockaddr_in6); 394 dst->sin6_family = AF_INET6; 395 dst->sin6_addr = ip6->ip6_dst; 396 397 rtalloc((struct route *)&ip6_forward_rt); 398 if (ip6_forward_rt.ro_rt == 0) { 399 ip6stat.ip6s_noroute++; 400 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_noroute); 401 if (mcopy) { 402 icmp6_error(mcopy, ICMP6_DST_UNREACH, 403 ICMP6_DST_UNREACH_NOROUTE, 0); 404 } 405 m_freem(m); 406 return; 407 } 408 } 409 rt = ip6_forward_rt.ro_rt; 410 #ifdef IPSEC 411 skip_routing:; 412 #endif 413 414 /* 415 * Source scope check: if a packet can't be delivered to its 416 * destination for the reason that the destination is beyond the scope 417 * of the source address, discard the packet and return an icmp6 418 * destination unreachable error with Code 2 (beyond scope of source 419 * address). We use a local copy of ip6_src, since in6_setscope() 420 * will possibly modify its first argument. 421 * [draft-ietf-ipngwg-icmp-v3-04.txt, Section 3.1] 422 */ 423 src_in6 = ip6->ip6_src; 424 if (in6_setscope(&src_in6, rt->rt_ifp, &outzone)) { 425 /* XXX: this should not happen */ 426 ip6stat.ip6s_cantforward++; 427 ip6stat.ip6s_badscope++; 428 m_freem(m); 429 return; 430 } 431 if (in6_setscope(&src_in6, m->m_pkthdr.rcvif, &inzone)) { 432 ip6stat.ip6s_cantforward++; 433 ip6stat.ip6s_badscope++; 434 m_freem(m); 435 return; 436 } 437 if (inzone != outzone 438 #ifdef IPSEC 439 && !ipsecrt 440 #endif 441 ) { 442 ip6stat.ip6s_cantforward++; 443 ip6stat.ip6s_badscope++; 444 in6_ifstat_inc(rt->rt_ifp, ifs6_in_discard); 445 446 if (ip6_log_time + ip6_log_interval < time_second) { 447 ip6_log_time = time_second; 448 log(LOG_DEBUG, 449 "cannot forward " 450 "src %s, dst %s, nxt %d, rcvif %s, outif %s\n", 451 ip6_sprintf(&ip6->ip6_src), 452 ip6_sprintf(&ip6->ip6_dst), 453 ip6->ip6_nxt, 454 if_name(m->m_pkthdr.rcvif), if_name(rt->rt_ifp)); 455 } 456 if (mcopy) 457 icmp6_error(mcopy, ICMP6_DST_UNREACH, 458 ICMP6_DST_UNREACH_BEYONDSCOPE, 0); 459 m_freem(m); 460 return; 461 } 462 463 /* 464 * Destination scope check: if a packet is going to break the scope 465 * zone of packet's destination address, discard it. This case should 466 * usually be prevented by appropriately-configured routing table, but 467 * we need an explicit check because we may mistakenly forward the 468 * packet to a different zone by (e.g.) a default route. 469 */ 470 dst_in6 = ip6->ip6_dst; 471 if (in6_setscope(&dst_in6, m->m_pkthdr.rcvif, &inzone) != 0 || 472 in6_setscope(&dst_in6, rt->rt_ifp, &outzone) != 0 || 473 inzone != outzone) { 474 ip6stat.ip6s_cantforward++; 475 ip6stat.ip6s_badscope++; 476 m_freem(m); 477 return; 478 } 479 480 if (m->m_pkthdr.len > IN6_LINKMTU(rt->rt_ifp)) { 481 in6_ifstat_inc(rt->rt_ifp, ifs6_in_toobig); 482 if (mcopy) { 483 u_long mtu; 484 #ifdef IPSEC 485 struct secpolicy *sp; 486 int ipsecerror; 487 size_t ipsechdrsiz; 488 #endif 489 490 mtu = IN6_LINKMTU(rt->rt_ifp); 491 #ifdef IPSEC 492 /* 493 * When we do IPsec tunnel ingress, we need to play 494 * with the link value (decrement IPsec header size 495 * from mtu value). The code is much simpler than v4 496 * case, as we have the outgoing interface for 497 * encapsulated packet as "rt->rt_ifp". 498 */ 499 sp = ipsec6_getpolicybyaddr(mcopy, IPSEC_DIR_OUTBOUND, 500 IP_FORWARDING, &ipsecerror); 501 if (sp) { 502 ipsechdrsiz = ipsec6_hdrsiz(mcopy, 503 IPSEC_DIR_OUTBOUND, NULL); 504 if (ipsechdrsiz < mtu) 505 mtu -= ipsechdrsiz; 506 } 507 508 /* 509 * if mtu becomes less than minimum MTU, 510 * tell minimum MTU (and I'll need to fragment it). 511 */ 512 if (mtu < IPV6_MMTU) 513 mtu = IPV6_MMTU; 514 #endif 515 icmp6_error(mcopy, ICMP6_PACKET_TOO_BIG, 0, mtu); 516 } 517 m_freem(m); 518 return; 519 } 520 521 if (rt->rt_flags & RTF_GATEWAY) 522 dst = (struct sockaddr_in6 *)rt->rt_gateway; 523 524 /* 525 * If we are to forward the packet using the same interface 526 * as one we got the packet from, perhaps we should send a redirect 527 * to sender to shortcut a hop. 528 * Only send redirect if source is sending directly to us, 529 * and if packet was not source routed (or has any options). 530 * Also, don't send redirect if forwarding using a route 531 * modified by a redirect. 532 */ 533 if (ip6_sendredirects && rt->rt_ifp == m->m_pkthdr.rcvif && !srcrt && 534 #ifdef IPSEC 535 !ipsecrt && 536 #endif 537 (rt->rt_flags & (RTF_DYNAMIC|RTF_MODIFIED)) == 0) { 538 if ((rt->rt_ifp->if_flags & IFF_POINTOPOINT) != 0) { 539 /* 540 * If the incoming interface is equal to the outgoing 541 * one, and the link attached to the interface is 542 * point-to-point, then it will be highly probable 543 * that a routing loop occurs. Thus, we immediately 544 * drop the packet and send an ICMPv6 error message. 545 * 546 * type/code is based on suggestion by Rich Draves. 547 * not sure if it is the best pick. 548 */ 549 icmp6_error(mcopy, ICMP6_DST_UNREACH, 550 ICMP6_DST_UNREACH_ADDR, 0); 551 m_freem(m); 552 return; 553 } 554 type = ND_REDIRECT; 555 } 556 557 /* 558 * Check with the firewall... 559 */ 560 if (ip6_fw_enable && ip6_fw_chk_ptr) { 561 u_short port = 0; 562 /* If ipfw says divert, we have to just drop packet */ 563 if ((*ip6_fw_chk_ptr)(&ip6, rt->rt_ifp, &port, &m)) { 564 m_freem(m); 565 goto freecopy; 566 } 567 if (!m) 568 goto freecopy; 569 } 570 571 /* 572 * Fake scoped addresses. Note that even link-local source or 573 * destinaion can appear, if the originating node just sends the 574 * packet to us (without address resolution for the destination). 575 * Since both icmp6_error and icmp6_redirect_output fill the embedded 576 * link identifiers, we can do this stuff after making a copy for 577 * returning an error. 578 */ 579 if ((rt->rt_ifp->if_flags & IFF_LOOPBACK) != 0) { 580 /* 581 * See corresponding comments in ip6_output. 582 * XXX: but is it possible that ip6_forward() sends a packet 583 * to a loopback interface? I don't think so, and thus 584 * I bark here. (jinmei@kame.net) 585 * XXX: it is common to route invalid packets to loopback. 586 * also, the codepath will be visited on use of ::1 in 587 * rthdr. (itojun) 588 */ 589 #if 1 590 if (0) 591 #else 592 if ((rt->rt_flags & (RTF_BLACKHOLE|RTF_REJECT)) == 0) 593 #endif 594 { 595 printf("ip6_forward: outgoing interface is loopback. " 596 "src %s, dst %s, nxt %d, rcvif %s, outif %s\n", 597 ip6_sprintf(&ip6->ip6_src), 598 ip6_sprintf(&ip6->ip6_dst), 599 ip6->ip6_nxt, if_name(m->m_pkthdr.rcvif), 600 if_name(rt->rt_ifp)); 601 } 602 603 /* we can just use rcvif in forwarding. */ 604 origifp = m->m_pkthdr.rcvif; 605 } 606 else 607 origifp = rt->rt_ifp; 608 /* 609 * clear embedded scope identifiers if necessary. 610 * in6_clearscope will touch the addresses only when necessary. 611 */ 612 in6_clearscope(&ip6->ip6_src); 613 in6_clearscope(&ip6->ip6_dst); 614 615 /* Jump over all PFIL processing if hooks are not active. */ 616 if (inet6_pfil_hook.ph_busy_count == -1) 617 goto pass; 618 619 /* Run through list of hooks for output packets. */ 620 error = pfil_run_hooks(&inet6_pfil_hook, &m, rt->rt_ifp, PFIL_OUT, NULL); 621 if (error != 0) 622 goto senderr; 623 if (m == NULL) 624 goto freecopy; 625 ip6 = mtod(m, struct ip6_hdr *); 626 627 pass: 628 error = nd6_output(rt->rt_ifp, origifp, m, dst, rt); 629 if (error) { 630 in6_ifstat_inc(rt->rt_ifp, ifs6_out_discard); 631 ip6stat.ip6s_cantforward++; 632 } else { 633 ip6stat.ip6s_forward++; 634 in6_ifstat_inc(rt->rt_ifp, ifs6_out_forward); 635 if (type) 636 ip6stat.ip6s_redirectsent++; 637 else { 638 if (mcopy) 639 goto freecopy; 640 } 641 } 642 643 senderr: 644 if (mcopy == NULL) 645 return; 646 switch (error) { 647 case 0: 648 if (type == ND_REDIRECT) { 649 icmp6_redirect_output(mcopy, rt); 650 return; 651 } 652 goto freecopy; 653 654 case EMSGSIZE: 655 /* xxx MTU is constant in PPP? */ 656 goto freecopy; 657 658 case ENOBUFS: 659 /* Tell source to slow down like source quench in IP? */ 660 goto freecopy; 661 662 case ENETUNREACH: /* shouldn't happen, checked above */ 663 case EHOSTUNREACH: 664 case ENETDOWN: 665 case EHOSTDOWN: 666 default: 667 type = ICMP6_DST_UNREACH; 668 code = ICMP6_DST_UNREACH_ADDR; 669 break; 670 } 671 icmp6_error(mcopy, type, code, 0); 672 return; 673 674 freecopy: 675 m_freem(mcopy); 676 return; 677 }
Cache object: 2de0ac8a406c67c7a3d5acfa41ad3f51
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