icmp6.c revision 166046
1/* $FreeBSD: head/sys/netinet6/icmp6.c 166046 2007-01-16 15:55:29Z ume $ */ 2/* $KAME: icmp6.c,v 1.211 2001/04/04 05:56:20 itojun 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/*- 34 * Copyright (c) 1982, 1986, 1988, 1993 35 * The Regents of the University of California. All rights reserved. 36 * 37 * Redistribution and use in source and binary forms, with or without 38 * modification, are permitted provided that the following conditions 39 * are met: 40 * 1. Redistributions of source code must retain the above copyright 41 * notice, this list of conditions and the following disclaimer. 42 * 2. Redistributions in binary form must reproduce the above copyright 43 * notice, this list of conditions and the following disclaimer in the 44 * documentation and/or other materials provided with the distribution. 45 * 4. Neither the name of the University nor the names of its contributors 46 * may be used to endorse or promote products derived from this software 47 * without specific prior written permission. 48 * 49 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 50 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 51 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 52 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 53 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 54 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 55 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 56 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 57 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 58 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 59 * SUCH DAMAGE. 60 * 61 * @(#)ip_icmp.c 8.2 (Berkeley) 1/4/94 62 */ 63 64#include "opt_inet.h" 65#include "opt_inet6.h" 66#include "opt_ipsec.h" 67 68#include <sys/param.h> 69#include <sys/domain.h> 70#include <sys/kernel.h> 71#include <sys/lock.h> 72#include <sys/malloc.h> 73#include <sys/mbuf.h> 74#include <sys/protosw.h> 75#include <sys/signalvar.h> 76#include <sys/socket.h> 77#include <sys/socketvar.h> 78#include <sys/sx.h> 79#include <sys/syslog.h> 80#include <sys/systm.h> 81#include <sys/time.h> 82 83#include <net/if.h> 84#include <net/if_dl.h> 85#include <net/if_types.h> 86#include <net/route.h> 87 88#include <netinet/in.h> 89#include <netinet/in_pcb.h> 90#include <netinet/in_var.h> 91#include <netinet/ip6.h> 92#include <netinet/icmp6.h> 93#include <netinet/tcp_var.h> 94#include <netinet6/in6_ifattach.h> 95#include <netinet6/in6_pcb.h> 96#include <netinet6/ip6protosw.h> 97#include <netinet6/ip6_var.h> 98#include <netinet6/scope6_var.h> 99#include <netinet6/mld6_var.h> 100#include <netinet6/nd6.h> 101 102#ifdef IPSEC 103#include <netinet6/ipsec.h> 104#include <netkey/key.h> 105#endif 106 107#ifdef FAST_IPSEC 108#include <netipsec/ipsec.h> 109#include <netipsec/key.h> 110#endif 111 112extern struct domain inet6domain; 113 114struct icmp6stat icmp6stat; 115 116extern struct inpcbinfo ripcbinfo; 117extern struct inpcbhead ripcb; 118extern int icmp6errppslim; 119static int icmp6errpps_count = 0; 120static struct timeval icmp6errppslim_last; 121extern int icmp6_nodeinfo; 122 123static void icmp6_errcount __P((struct icmp6errstat *, int, int)); 124static int icmp6_rip6_input __P((struct mbuf **, int)); 125static int icmp6_ratelimit __P((const struct in6_addr *, const int, const int)); 126static const char *icmp6_redirect_diag __P((struct in6_addr *, 127 struct in6_addr *, struct in6_addr *)); 128static struct mbuf *ni6_input __P((struct mbuf *, int)); 129static struct mbuf *ni6_nametodns __P((const char *, int, int)); 130static int ni6_dnsmatch __P((const char *, int, const char *, int)); 131static int ni6_addrs __P((struct icmp6_nodeinfo *, struct mbuf *, 132 struct ifnet **, struct in6_addr *)); 133static int ni6_store_addrs __P((struct icmp6_nodeinfo *, struct icmp6_nodeinfo *, 134 struct ifnet *, int)); 135static int icmp6_notify_error __P((struct mbuf **, int, int, int)); 136 137 138void 139icmp6_init() 140{ 141 mld6_init(); 142} 143 144static void 145icmp6_errcount(stat, type, code) 146 struct icmp6errstat *stat; 147 int type, code; 148{ 149 switch (type) { 150 case ICMP6_DST_UNREACH: 151 switch (code) { 152 case ICMP6_DST_UNREACH_NOROUTE: 153 stat->icp6errs_dst_unreach_noroute++; 154 return; 155 case ICMP6_DST_UNREACH_ADMIN: 156 stat->icp6errs_dst_unreach_admin++; 157 return; 158 case ICMP6_DST_UNREACH_BEYONDSCOPE: 159 stat->icp6errs_dst_unreach_beyondscope++; 160 return; 161 case ICMP6_DST_UNREACH_ADDR: 162 stat->icp6errs_dst_unreach_addr++; 163 return; 164 case ICMP6_DST_UNREACH_NOPORT: 165 stat->icp6errs_dst_unreach_noport++; 166 return; 167 } 168 break; 169 case ICMP6_PACKET_TOO_BIG: 170 stat->icp6errs_packet_too_big++; 171 return; 172 case ICMP6_TIME_EXCEEDED: 173 switch (code) { 174 case ICMP6_TIME_EXCEED_TRANSIT: 175 stat->icp6errs_time_exceed_transit++; 176 return; 177 case ICMP6_TIME_EXCEED_REASSEMBLY: 178 stat->icp6errs_time_exceed_reassembly++; 179 return; 180 } 181 break; 182 case ICMP6_PARAM_PROB: 183 switch (code) { 184 case ICMP6_PARAMPROB_HEADER: 185 stat->icp6errs_paramprob_header++; 186 return; 187 case ICMP6_PARAMPROB_NEXTHEADER: 188 stat->icp6errs_paramprob_nextheader++; 189 return; 190 case ICMP6_PARAMPROB_OPTION: 191 stat->icp6errs_paramprob_option++; 192 return; 193 } 194 break; 195 case ND_REDIRECT: 196 stat->icp6errs_redirect++; 197 return; 198 } 199 stat->icp6errs_unknown++; 200} 201 202/* 203 * A wrapper function for icmp6_error() necessary when the erroneous packet 204 * may not contain enough scope zone information. 205 */ 206void 207icmp6_error2(m, type, code, param, ifp) 208 struct mbuf *m; 209 int type, code, param; 210 struct ifnet *ifp; 211{ 212 struct ip6_hdr *ip6; 213 214 if (ifp == NULL) 215 return; 216 217#ifndef PULLDOWN_TEST 218 IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), ); 219#else 220 if (m->m_len < sizeof(struct ip6_hdr)) { 221 m = m_pullup(m, sizeof(struct ip6_hdr)); 222 if (m == NULL) 223 return; 224 } 225#endif 226 227 ip6 = mtod(m, struct ip6_hdr *); 228 229 if (in6_setscope(&ip6->ip6_src, ifp, NULL) != 0) 230 return; 231 if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0) 232 return; 233 234 icmp6_error(m, type, code, param); 235} 236 237/* 238 * Generate an error packet of type error in response to bad IP6 packet. 239 */ 240void 241icmp6_error(m, type, code, param) 242 struct mbuf *m; 243 int type, code, param; 244{ 245 struct ip6_hdr *oip6, *nip6; 246 struct icmp6_hdr *icmp6; 247 u_int preplen; 248 int off; 249 int nxt; 250 251 icmp6stat.icp6s_error++; 252 253 /* count per-type-code statistics */ 254 icmp6_errcount(&icmp6stat.icp6s_outerrhist, type, code); 255 256#ifdef M_DECRYPTED /*not openbsd*/ 257 if (m->m_flags & M_DECRYPTED) { 258 icmp6stat.icp6s_canterror++; 259 goto freeit; 260 } 261#endif 262 263#ifndef PULLDOWN_TEST 264 IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), ); 265#else 266 if (m->m_len < sizeof(struct ip6_hdr)) { 267 m = m_pullup(m, sizeof(struct ip6_hdr)); 268 if (m == NULL) 269 return; 270 } 271#endif 272 oip6 = mtod(m, struct ip6_hdr *); 273 274 /* 275 * If the destination address of the erroneous packet is a multicast 276 * address, or the packet was sent using link-layer multicast, 277 * we should basically suppress sending an error (RFC 2463, Section 278 * 2.4). 279 * We have two exceptions (the item e.2 in that section): 280 * - the Pakcet Too Big message can be sent for path MTU discovery. 281 * - the Parameter Problem Message that can be allowed an icmp6 error 282 * in the option type field. This check has been done in 283 * ip6_unknown_opt(), so we can just check the type and code. 284 */ 285 if ((m->m_flags & (M_BCAST|M_MCAST) || 286 IN6_IS_ADDR_MULTICAST(&oip6->ip6_dst)) && 287 (type != ICMP6_PACKET_TOO_BIG && 288 (type != ICMP6_PARAM_PROB || 289 code != ICMP6_PARAMPROB_OPTION))) 290 goto freeit; 291 292 /* 293 * RFC 2463, 2.4 (e.5): source address check. 294 * XXX: the case of anycast source? 295 */ 296 if (IN6_IS_ADDR_UNSPECIFIED(&oip6->ip6_src) || 297 IN6_IS_ADDR_MULTICAST(&oip6->ip6_src)) 298 goto freeit; 299 300 /* 301 * If we are about to send ICMPv6 against ICMPv6 error/redirect, 302 * don't do it. 303 */ 304 nxt = -1; 305 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); 306 if (off >= 0 && nxt == IPPROTO_ICMPV6) { 307 struct icmp6_hdr *icp; 308 309#ifndef PULLDOWN_TEST 310 IP6_EXTHDR_CHECK(m, 0, off + sizeof(struct icmp6_hdr), ); 311 icp = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 312#else 313 IP6_EXTHDR_GET(icp, struct icmp6_hdr *, m, off, 314 sizeof(*icp)); 315 if (icp == NULL) { 316 icmp6stat.icp6s_tooshort++; 317 return; 318 } 319#endif 320 if (icp->icmp6_type < ICMP6_ECHO_REQUEST || 321 icp->icmp6_type == ND_REDIRECT) { 322 /* 323 * ICMPv6 error 324 * Special case: for redirect (which is 325 * informational) we must not send icmp6 error. 326 */ 327 icmp6stat.icp6s_canterror++; 328 goto freeit; 329 } else { 330 /* ICMPv6 informational - send the error */ 331 } 332 } else { 333 /* non-ICMPv6 - send the error */ 334 } 335 336 oip6 = mtod(m, struct ip6_hdr *); /* adjust pointer */ 337 338 /* Finally, do rate limitation check. */ 339 if (icmp6_ratelimit(&oip6->ip6_src, type, code)) { 340 icmp6stat.icp6s_toofreq++; 341 goto freeit; 342 } 343 344 /* 345 * OK, ICMP6 can be generated. 346 */ 347 348 if (m->m_pkthdr.len >= ICMPV6_PLD_MAXLEN) 349 m_adj(m, ICMPV6_PLD_MAXLEN - m->m_pkthdr.len); 350 351 preplen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 352 M_PREPEND(m, preplen, M_DONTWAIT); 353 if (m && m->m_len < preplen) 354 m = m_pullup(m, preplen); 355 if (m == NULL) { 356 nd6log((LOG_DEBUG, "ENOBUFS in icmp6_error %d\n", __LINE__)); 357 return; 358 } 359 360 nip6 = mtod(m, struct ip6_hdr *); 361 nip6->ip6_src = oip6->ip6_src; 362 nip6->ip6_dst = oip6->ip6_dst; 363 364 in6_clearscope(&oip6->ip6_src); 365 in6_clearscope(&oip6->ip6_dst); 366 367 icmp6 = (struct icmp6_hdr *)(nip6 + 1); 368 icmp6->icmp6_type = type; 369 icmp6->icmp6_code = code; 370 icmp6->icmp6_pptr = htonl((u_int32_t)param); 371 372 /* 373 * icmp6_reflect() is designed to be in the input path. 374 * icmp6_error() can be called from both input and output path, 375 * and if we are in output path rcvif could contain bogus value. 376 * clear m->m_pkthdr.rcvif for safety, we should have enough scope 377 * information in ip header (nip6). 378 */ 379 m->m_pkthdr.rcvif = NULL; 380 381 icmp6stat.icp6s_outhist[type]++; 382 icmp6_reflect(m, sizeof(struct ip6_hdr)); /* header order: IPv6 - ICMPv6 */ 383 384 return; 385 386 freeit: 387 /* 388 * If we can't tell whether or not we can generate ICMP6, free it. 389 */ 390 m_freem(m); 391} 392 393/* 394 * Process a received ICMP6 message. 395 */ 396int 397icmp6_input(mp, offp, proto) 398 struct mbuf **mp; 399 int *offp, proto; 400{ 401 struct mbuf *m = *mp, *n; 402 struct ip6_hdr *ip6, *nip6; 403 struct icmp6_hdr *icmp6, *nicmp6; 404 int off = *offp; 405 int icmp6len = m->m_pkthdr.len - *offp; 406 int code, sum, noff; 407 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 408 409#ifndef PULLDOWN_TEST 410 IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_hdr), IPPROTO_DONE); 411 /* m might change if M_LOOP. So, call mtod after this */ 412#endif 413 414 /* 415 * Locate icmp6 structure in mbuf, and check 416 * that not corrupted and of at least minimum length 417 */ 418 419 ip6 = mtod(m, struct ip6_hdr *); 420 if (icmp6len < sizeof(struct icmp6_hdr)) { 421 icmp6stat.icp6s_tooshort++; 422 goto freeit; 423 } 424 425 /* 426 * calculate the checksum 427 */ 428#ifndef PULLDOWN_TEST 429 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off); 430#else 431 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 432 if (icmp6 == NULL) { 433 icmp6stat.icp6s_tooshort++; 434 return IPPROTO_DONE; 435 } 436#endif 437 code = icmp6->icmp6_code; 438 439 if ((sum = in6_cksum(m, IPPROTO_ICMPV6, off, icmp6len)) != 0) { 440 nd6log((LOG_ERR, 441 "ICMP6 checksum error(%d|%x) %s\n", 442 icmp6->icmp6_type, sum, 443 ip6_sprintf(ip6bufs, &ip6->ip6_src))); 444 icmp6stat.icp6s_checksum++; 445 goto freeit; 446 } 447 448 if (faithprefix_p != NULL && (*faithprefix_p)(&ip6->ip6_dst)) { 449 /* 450 * Deliver very specific ICMP6 type only. 451 * This is important to deliver TOOBIG. Otherwise PMTUD 452 * will not work. 453 */ 454 switch (icmp6->icmp6_type) { 455 case ICMP6_DST_UNREACH: 456 case ICMP6_PACKET_TOO_BIG: 457 case ICMP6_TIME_EXCEEDED: 458 break; 459 default: 460 goto freeit; 461 } 462 } 463 464 icmp6stat.icp6s_inhist[icmp6->icmp6_type]++; 465 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_msg); 466 if (icmp6->icmp6_type < ICMP6_INFOMSG_MASK) 467 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_error); 468 469 switch (icmp6->icmp6_type) { 470 case ICMP6_DST_UNREACH: 471 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_dstunreach); 472 switch (code) { 473 case ICMP6_DST_UNREACH_NOROUTE: 474 code = PRC_UNREACH_NET; 475 break; 476 case ICMP6_DST_UNREACH_ADMIN: 477 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_adminprohib); 478 code = PRC_UNREACH_PROTOCOL; /* is this a good code? */ 479 break; 480 case ICMP6_DST_UNREACH_ADDR: 481 code = PRC_HOSTDEAD; 482 break; 483 case ICMP6_DST_UNREACH_BEYONDSCOPE: 484 /* I mean "source address was incorrect." */ 485 code = PRC_PARAMPROB; 486 break; 487 case ICMP6_DST_UNREACH_NOPORT: 488 code = PRC_UNREACH_PORT; 489 break; 490 default: 491 goto badcode; 492 } 493 goto deliver; 494 break; 495 496 case ICMP6_PACKET_TOO_BIG: 497 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_pkttoobig); 498 499 /* validation is made in icmp6_mtudisc_update */ 500 501 code = PRC_MSGSIZE; 502 503 /* 504 * Updating the path MTU will be done after examining 505 * intermediate extension headers. 506 */ 507 goto deliver; 508 break; 509 510 case ICMP6_TIME_EXCEEDED: 511 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_timeexceed); 512 switch (code) { 513 case ICMP6_TIME_EXCEED_TRANSIT: 514 code = PRC_TIMXCEED_INTRANS; 515 break; 516 case ICMP6_TIME_EXCEED_REASSEMBLY: 517 code = PRC_TIMXCEED_REASS; 518 break; 519 default: 520 goto badcode; 521 } 522 goto deliver; 523 break; 524 525 case ICMP6_PARAM_PROB: 526 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_paramprob); 527 switch (code) { 528 case ICMP6_PARAMPROB_NEXTHEADER: 529 code = PRC_UNREACH_PROTOCOL; 530 break; 531 case ICMP6_PARAMPROB_HEADER: 532 case ICMP6_PARAMPROB_OPTION: 533 code = PRC_PARAMPROB; 534 break; 535 default: 536 goto badcode; 537 } 538 goto deliver; 539 break; 540 541 case ICMP6_ECHO_REQUEST: 542 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echo); 543 if (code != 0) 544 goto badcode; 545 if ((n = m_copy(m, 0, M_COPYALL)) == NULL) { 546 /* Give up remote */ 547 break; 548 } 549 if ((n->m_flags & M_EXT) != 0 550 || n->m_len < off + sizeof(struct icmp6_hdr)) { 551 struct mbuf *n0 = n; 552 const int maxlen = sizeof(*nip6) + sizeof(*nicmp6); 553 int n0len; 554 555 MGETHDR(n, M_DONTWAIT, n0->m_type); 556 n0len = n0->m_pkthdr.len; /* save for use below */ 557 if (n) 558 M_MOVE_PKTHDR(n, n0); 559 if (n && maxlen >= MHLEN) { 560 MCLGET(n, M_DONTWAIT); 561 if ((n->m_flags & M_EXT) == 0) { 562 m_free(n); 563 n = NULL; 564 } 565 } 566 if (n == NULL) { 567 /* Give up remote */ 568 m_freem(n0); 569 break; 570 } 571 /* 572 * Copy IPv6 and ICMPv6 only. 573 */ 574 nip6 = mtod(n, struct ip6_hdr *); 575 bcopy(ip6, nip6, sizeof(struct ip6_hdr)); 576 nicmp6 = (struct icmp6_hdr *)(nip6 + 1); 577 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr)); 578 noff = sizeof(struct ip6_hdr); 579 /* new mbuf contains only ipv6+icmpv6 headers */ 580 n->m_len = noff + sizeof(struct icmp6_hdr); 581 /* 582 * Adjust mbuf. ip6_plen will be adjusted in 583 * ip6_output(). 584 */ 585 m_adj(n0, off + sizeof(struct icmp6_hdr)); 586 /* recalculate complete packet size */ 587 n->m_pkthdr.len = n0len + (noff - off); 588 n->m_next = n0; 589 } else { 590 nip6 = mtod(n, struct ip6_hdr *); 591 IP6_EXTHDR_GET(nicmp6, struct icmp6_hdr *, n, off, 592 sizeof(*nicmp6)); 593 noff = off; 594 } 595 nicmp6->icmp6_type = ICMP6_ECHO_REPLY; 596 nicmp6->icmp6_code = 0; 597 if (n) { 598 icmp6stat.icp6s_reflect++; 599 icmp6stat.icp6s_outhist[ICMP6_ECHO_REPLY]++; 600 icmp6_reflect(n, noff); 601 } 602 break; 603 604 case ICMP6_ECHO_REPLY: 605 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echoreply); 606 if (code != 0) 607 goto badcode; 608 break; 609 610 case MLD_LISTENER_QUERY: 611 case MLD_LISTENER_REPORT: 612 if (icmp6len < sizeof(struct mld_hdr)) 613 goto badlen; 614 if (icmp6->icmp6_type == MLD_LISTENER_QUERY) /* XXX: ugly... */ 615 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldquery); 616 else 617 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldreport); 618 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 619 /* give up local */ 620 mld6_input(m, off); 621 m = NULL; 622 goto freeit; 623 } 624 mld6_input(n, off); 625 /* m stays. */ 626 break; 627 628 case MLD_LISTENER_DONE: 629 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mlddone); 630 if (icmp6len < sizeof(struct mld_hdr)) /* necessary? */ 631 goto badlen; 632 break; /* nothing to be done in kernel */ 633 634 case MLD_MTRACE_RESP: 635 case MLD_MTRACE: 636 /* XXX: these two are experimental. not officially defined. */ 637 /* XXX: per-interface statistics? */ 638 break; /* just pass it to applications */ 639 640 case ICMP6_WRUREQUEST: /* ICMP6_FQDN_QUERY */ 641 { 642 enum { WRU, FQDN } mode; 643 644 if (!icmp6_nodeinfo) 645 break; 646 647 if (icmp6len == sizeof(struct icmp6_hdr) + 4) 648 mode = WRU; 649 else if (icmp6len >= sizeof(struct icmp6_nodeinfo)) 650 mode = FQDN; 651 else 652 goto badlen; 653 654#define hostnamelen strlen(hostname) 655 if (mode == FQDN) { 656#ifndef PULLDOWN_TEST 657 IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_nodeinfo), 658 IPPROTO_DONE); 659#endif 660 n = m_copy(m, 0, M_COPYALL); 661 if (n) 662 n = ni6_input(n, off); 663 /* XXX meaningless if n == NULL */ 664 noff = sizeof(struct ip6_hdr); 665 } else { 666 u_char *p; 667 int maxlen, maxhlen; 668 669 if ((icmp6_nodeinfo & 5) != 5) 670 break; 671 672 if (code != 0) 673 goto badcode; 674 maxlen = sizeof(*nip6) + sizeof(*nicmp6) + 4; 675 if (maxlen >= MCLBYTES) { 676 /* Give up remote */ 677 break; 678 } 679 MGETHDR(n, M_DONTWAIT, m->m_type); 680 if (n && maxlen > MHLEN) { 681 MCLGET(n, M_DONTWAIT); 682 if ((n->m_flags & M_EXT) == 0) { 683 m_free(n); 684 n = NULL; 685 } 686 } 687 if (!m_dup_pkthdr(n, m, M_DONTWAIT)) { 688 /* 689 * Previous code did a blind M_COPY_PKTHDR 690 * and said "just for rcvif". If true, then 691 * we could tolerate the dup failing (due to 692 * the deep copy of the tag chain). For now 693 * be conservative and just fail. 694 */ 695 m_free(n); 696 n = NULL; 697 } 698 if (n == NULL) { 699 /* Give up remote */ 700 break; 701 } 702 n->m_pkthdr.rcvif = NULL; 703 n->m_len = 0; 704 maxhlen = M_TRAILINGSPACE(n) - maxlen; 705 if (maxhlen > hostnamelen) 706 maxhlen = hostnamelen; 707 /* 708 * Copy IPv6 and ICMPv6 only. 709 */ 710 nip6 = mtod(n, struct ip6_hdr *); 711 bcopy(ip6, nip6, sizeof(struct ip6_hdr)); 712 nicmp6 = (struct icmp6_hdr *)(nip6 + 1); 713 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr)); 714 p = (u_char *)(nicmp6 + 1); 715 bzero(p, 4); 716 bcopy(hostname, p + 4, maxhlen); /* meaningless TTL */ 717 noff = sizeof(struct ip6_hdr); 718 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) + 719 sizeof(struct icmp6_hdr) + 4 + maxhlen; 720 nicmp6->icmp6_type = ICMP6_WRUREPLY; 721 nicmp6->icmp6_code = 0; 722 } 723#undef hostnamelen 724 if (n) { 725 icmp6stat.icp6s_reflect++; 726 icmp6stat.icp6s_outhist[ICMP6_WRUREPLY]++; 727 icmp6_reflect(n, noff); 728 } 729 break; 730 } 731 732 case ICMP6_WRUREPLY: 733 if (code != 0) 734 goto badcode; 735 break; 736 737 case ND_ROUTER_SOLICIT: 738 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routersolicit); 739 if (code != 0) 740 goto badcode; 741 if (icmp6len < sizeof(struct nd_router_solicit)) 742 goto badlen; 743 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 744 /* give up local */ 745 nd6_rs_input(m, off, icmp6len); 746 m = NULL; 747 goto freeit; 748 } 749 nd6_rs_input(n, off, icmp6len); 750 /* m stays. */ 751 break; 752 753 case ND_ROUTER_ADVERT: 754 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routeradvert); 755 if (code != 0) 756 goto badcode; 757 if (icmp6len < sizeof(struct nd_router_advert)) 758 goto badlen; 759 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 760 /* give up local */ 761 nd6_ra_input(m, off, icmp6len); 762 m = NULL; 763 goto freeit; 764 } 765 nd6_ra_input(n, off, icmp6len); 766 /* m stays. */ 767 break; 768 769 case ND_NEIGHBOR_SOLICIT: 770 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighborsolicit); 771 if (code != 0) 772 goto badcode; 773 if (icmp6len < sizeof(struct nd_neighbor_solicit)) 774 goto badlen; 775 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 776 /* give up local */ 777 nd6_ns_input(m, off, icmp6len); 778 m = NULL; 779 goto freeit; 780 } 781 nd6_ns_input(n, off, icmp6len); 782 /* m stays. */ 783 break; 784 785 case ND_NEIGHBOR_ADVERT: 786 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighboradvert); 787 if (code != 0) 788 goto badcode; 789 if (icmp6len < sizeof(struct nd_neighbor_advert)) 790 goto badlen; 791 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 792 /* give up local */ 793 nd6_na_input(m, off, icmp6len); 794 m = NULL; 795 goto freeit; 796 } 797 nd6_na_input(n, off, icmp6len); 798 /* m stays. */ 799 break; 800 801 case ND_REDIRECT: 802 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_redirect); 803 if (code != 0) 804 goto badcode; 805 if (icmp6len < sizeof(struct nd_redirect)) 806 goto badlen; 807 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 808 /* give up local */ 809 icmp6_redirect_input(m, off); 810 m = NULL; 811 goto freeit; 812 } 813 icmp6_redirect_input(n, off); 814 /* m stays. */ 815 break; 816 817 case ICMP6_ROUTER_RENUMBERING: 818 if (code != ICMP6_ROUTER_RENUMBERING_COMMAND && 819 code != ICMP6_ROUTER_RENUMBERING_RESULT) 820 goto badcode; 821 if (icmp6len < sizeof(struct icmp6_router_renum)) 822 goto badlen; 823 break; 824 825 default: 826 nd6log((LOG_DEBUG, 827 "icmp6_input: unknown type %d(src=%s, dst=%s, ifid=%d)\n", 828 icmp6->icmp6_type, ip6_sprintf(ip6bufs, &ip6->ip6_src), 829 ip6_sprintf(ip6bufd, &ip6->ip6_dst), 830 m->m_pkthdr.rcvif ? m->m_pkthdr.rcvif->if_index : 0)); 831 if (icmp6->icmp6_type < ICMP6_ECHO_REQUEST) { 832 /* ICMPv6 error: MUST deliver it by spec... */ 833 code = PRC_NCMDS; 834 /* deliver */ 835 } else { 836 /* ICMPv6 informational: MUST not deliver */ 837 break; 838 } 839 deliver: 840 if (icmp6_notify_error(&m, off, icmp6len, code)) { 841 /* In this case, m should've been freed. */ 842 return (IPPROTO_DONE); 843 } 844 break; 845 846 badcode: 847 icmp6stat.icp6s_badcode++; 848 break; 849 850 badlen: 851 icmp6stat.icp6s_badlen++; 852 break; 853 } 854 855 /* deliver the packet to appropriate sockets */ 856 icmp6_rip6_input(&m, *offp); 857 858 return IPPROTO_DONE; 859 860 freeit: 861 m_freem(m); 862 return IPPROTO_DONE; 863} 864 865static int 866icmp6_notify_error(mp, off, icmp6len, code) 867 struct mbuf **mp; 868 int off, icmp6len, code; 869{ 870 struct mbuf *m = *mp; 871 struct icmp6_hdr *icmp6; 872 struct ip6_hdr *eip6; 873 u_int32_t notifymtu; 874 struct sockaddr_in6 icmp6src, icmp6dst; 875 876 if (icmp6len < sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr)) { 877 icmp6stat.icp6s_tooshort++; 878 goto freeit; 879 } 880#ifndef PULLDOWN_TEST 881 IP6_EXTHDR_CHECK(m, off, 882 sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr), -1); 883 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 884#else 885 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, 886 sizeof(*icmp6) + sizeof(struct ip6_hdr)); 887 if (icmp6 == NULL) { 888 icmp6stat.icp6s_tooshort++; 889 return (-1); 890 } 891#endif 892 eip6 = (struct ip6_hdr *)(icmp6 + 1); 893 894 /* Detect the upper level protocol */ 895 { 896 void (*ctlfunc) __P((int, struct sockaddr *, void *)); 897 u_int8_t nxt = eip6->ip6_nxt; 898 int eoff = off + sizeof(struct icmp6_hdr) + 899 sizeof(struct ip6_hdr); 900 struct ip6ctlparam ip6cp; 901 struct in6_addr *finaldst = NULL; 902 int icmp6type = icmp6->icmp6_type; 903 struct ip6_frag *fh; 904 struct ip6_rthdr *rth; 905 struct ip6_rthdr0 *rth0; 906 int rthlen; 907 908 while (1) { /* XXX: should avoid infinite loop explicitly? */ 909 struct ip6_ext *eh; 910 911 switch (nxt) { 912 case IPPROTO_HOPOPTS: 913 case IPPROTO_DSTOPTS: 914 case IPPROTO_AH: 915#ifndef PULLDOWN_TEST 916 IP6_EXTHDR_CHECK(m, 0, 917 eoff + sizeof(struct ip6_ext), -1); 918 eh = (struct ip6_ext *)(mtod(m, caddr_t) + eoff); 919#else 920 IP6_EXTHDR_GET(eh, struct ip6_ext *, m, 921 eoff, sizeof(*eh)); 922 if (eh == NULL) { 923 icmp6stat.icp6s_tooshort++; 924 return (-1); 925 } 926#endif 927 928 if (nxt == IPPROTO_AH) 929 eoff += (eh->ip6e_len + 2) << 2; 930 else 931 eoff += (eh->ip6e_len + 1) << 3; 932 nxt = eh->ip6e_nxt; 933 break; 934 case IPPROTO_ROUTING: 935 /* 936 * When the erroneous packet contains a 937 * routing header, we should examine the 938 * header to determine the final destination. 939 * Otherwise, we can't properly update 940 * information that depends on the final 941 * destination (e.g. path MTU). 942 */ 943#ifndef PULLDOWN_TEST 944 IP6_EXTHDR_CHECK(m, 0, eoff + sizeof(*rth), -1); 945 rth = (struct ip6_rthdr *) 946 (mtod(m, caddr_t) + eoff); 947#else 948 IP6_EXTHDR_GET(rth, struct ip6_rthdr *, m, 949 eoff, sizeof(*rth)); 950 if (rth == NULL) { 951 icmp6stat.icp6s_tooshort++; 952 return (-1); 953 } 954#endif 955 rthlen = (rth->ip6r_len + 1) << 3; 956 /* 957 * XXX: currently there is no 958 * officially defined type other 959 * than type-0. 960 * Note that if the segment left field 961 * is 0, all intermediate hops must 962 * have been passed. 963 */ 964 if (rth->ip6r_segleft && 965 rth->ip6r_type == IPV6_RTHDR_TYPE_0) { 966 int hops; 967 968#ifndef PULLDOWN_TEST 969 IP6_EXTHDR_CHECK(m, 0, eoff + rthlen, -1); 970 rth0 = (struct ip6_rthdr0 *) 971 (mtod(m, caddr_t) + eoff); 972#else 973 IP6_EXTHDR_GET(rth0, 974 struct ip6_rthdr0 *, m, 975 eoff, rthlen); 976 if (rth0 == NULL) { 977 icmp6stat.icp6s_tooshort++; 978 return (-1); 979 } 980#endif 981 /* just ignore a bogus header */ 982 if ((rth0->ip6r0_len % 2) == 0 && 983 (hops = rth0->ip6r0_len/2)) 984 finaldst = (struct in6_addr *)(rth0 + 1) + (hops - 1); 985 } 986 eoff += rthlen; 987 nxt = rth->ip6r_nxt; 988 break; 989 case IPPROTO_FRAGMENT: 990#ifndef PULLDOWN_TEST 991 IP6_EXTHDR_CHECK(m, 0, eoff + 992 sizeof(struct ip6_frag), -1); 993 fh = (struct ip6_frag *)(mtod(m, caddr_t) + 994 eoff); 995#else 996 IP6_EXTHDR_GET(fh, struct ip6_frag *, m, 997 eoff, sizeof(*fh)); 998 if (fh == NULL) { 999 icmp6stat.icp6s_tooshort++; 1000 return (-1); 1001 } 1002#endif 1003 /* 1004 * Data after a fragment header is meaningless 1005 * unless it is the first fragment, but 1006 * we'll go to the notify label for path MTU 1007 * discovery. 1008 */ 1009 if (fh->ip6f_offlg & IP6F_OFF_MASK) 1010 goto notify; 1011 1012 eoff += sizeof(struct ip6_frag); 1013 nxt = fh->ip6f_nxt; 1014 break; 1015 default: 1016 /* 1017 * This case includes ESP and the No Next 1018 * Header. In such cases going to the notify 1019 * label does not have any meaning 1020 * (i.e. ctlfunc will be NULL), but we go 1021 * anyway since we might have to update 1022 * path MTU information. 1023 */ 1024 goto notify; 1025 } 1026 } 1027 notify: 1028#ifndef PULLDOWN_TEST 1029 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 1030#else 1031 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, 1032 sizeof(*icmp6) + sizeof(struct ip6_hdr)); 1033 if (icmp6 == NULL) { 1034 icmp6stat.icp6s_tooshort++; 1035 return (-1); 1036 } 1037#endif 1038 1039 /* 1040 * retrieve parameters from the inner IPv6 header, and convert 1041 * them into sockaddr structures. 1042 * XXX: there is no guarantee that the source or destination 1043 * addresses of the inner packet are in the same scope as 1044 * the addresses of the icmp packet. But there is no other 1045 * way to determine the zone. 1046 */ 1047 eip6 = (struct ip6_hdr *)(icmp6 + 1); 1048 1049 bzero(&icmp6dst, sizeof(icmp6dst)); 1050 icmp6dst.sin6_len = sizeof(struct sockaddr_in6); 1051 icmp6dst.sin6_family = AF_INET6; 1052 if (finaldst == NULL) 1053 icmp6dst.sin6_addr = eip6->ip6_dst; 1054 else 1055 icmp6dst.sin6_addr = *finaldst; 1056 if (in6_setscope(&icmp6dst.sin6_addr, m->m_pkthdr.rcvif, NULL)) 1057 goto freeit; 1058 bzero(&icmp6src, sizeof(icmp6src)); 1059 icmp6src.sin6_len = sizeof(struct sockaddr_in6); 1060 icmp6src.sin6_family = AF_INET6; 1061 icmp6src.sin6_addr = eip6->ip6_src; 1062 if (in6_setscope(&icmp6src.sin6_addr, m->m_pkthdr.rcvif, NULL)) 1063 goto freeit; 1064 icmp6src.sin6_flowinfo = 1065 (eip6->ip6_flow & IPV6_FLOWLABEL_MASK); 1066 1067 if (finaldst == NULL) 1068 finaldst = &eip6->ip6_dst; 1069 ip6cp.ip6c_m = m; 1070 ip6cp.ip6c_icmp6 = icmp6; 1071 ip6cp.ip6c_ip6 = (struct ip6_hdr *)(icmp6 + 1); 1072 ip6cp.ip6c_off = eoff; 1073 ip6cp.ip6c_finaldst = finaldst; 1074 ip6cp.ip6c_src = &icmp6src; 1075 ip6cp.ip6c_nxt = nxt; 1076 1077 if (icmp6type == ICMP6_PACKET_TOO_BIG) { 1078 notifymtu = ntohl(icmp6->icmp6_mtu); 1079 ip6cp.ip6c_cmdarg = (void *)¬ifymtu; 1080 icmp6_mtudisc_update(&ip6cp, 1); /*XXX*/ 1081 } 1082 1083 ctlfunc = (void (*) __P((int, struct sockaddr *, void *))) 1084 (inet6sw[ip6_protox[nxt]].pr_ctlinput); 1085 if (ctlfunc) { 1086 (void) (*ctlfunc)(code, (struct sockaddr *)&icmp6dst, 1087 &ip6cp); 1088 } 1089 } 1090 *mp = m; 1091 return (0); 1092 1093 freeit: 1094 m_freem(m); 1095 return (-1); 1096} 1097 1098void 1099icmp6_mtudisc_update(ip6cp, validated) 1100 struct ip6ctlparam *ip6cp; 1101 int validated; 1102{ 1103 struct in6_addr *dst = ip6cp->ip6c_finaldst; 1104 struct icmp6_hdr *icmp6 = ip6cp->ip6c_icmp6; 1105 struct mbuf *m = ip6cp->ip6c_m; /* will be necessary for scope issue */ 1106 u_int mtu = ntohl(icmp6->icmp6_mtu); 1107 struct in_conninfo inc; 1108 1109#if 0 1110 /* 1111 * RFC2460 section 5, last paragraph. 1112 * even though minimum link MTU for IPv6 is IPV6_MMTU, 1113 * we may see ICMPv6 too big with mtu < IPV6_MMTU 1114 * due to packet translator in the middle. 1115 * see ip6_output() and ip6_getpmtu() "alwaysfrag" case for 1116 * special handling. 1117 */ 1118 if (mtu < IPV6_MMTU) 1119 return; 1120#endif 1121 1122 /* 1123 * we reject ICMPv6 too big with abnormally small value. 1124 * XXX what is the good definition of "abnormally small"? 1125 */ 1126 if (mtu < sizeof(struct ip6_hdr) + sizeof(struct ip6_frag) + 8) 1127 return; 1128 1129 if (!validated) 1130 return; 1131 1132 bzero(&inc, sizeof(inc)); 1133 inc.inc_flags = 1; /* IPv6 */ 1134 inc.inc6_faddr = *dst; 1135 if (in6_setscope(&inc.inc6_faddr, m->m_pkthdr.rcvif, NULL)) 1136 return; 1137 1138 if (mtu < tcp_maxmtu6(&inc, NULL)) { 1139 tcp_hc_updatemtu(&inc, mtu); 1140 icmp6stat.icp6s_pmtuchg++; 1141 } 1142} 1143 1144/* 1145 * Process a Node Information Query packet, based on 1146 * draft-ietf-ipngwg-icmp-name-lookups-07. 1147 * 1148 * Spec incompatibilities: 1149 * - IPv6 Subject address handling 1150 * - IPv4 Subject address handling support missing 1151 * - Proxy reply (answer even if it's not for me) 1152 * - joins NI group address at in6_ifattach() time only, does not cope 1153 * with hostname changes by sethostname(3) 1154 */ 1155#define hostnamelen strlen(hostname) 1156static struct mbuf * 1157ni6_input(m, off) 1158 struct mbuf *m; 1159 int off; 1160{ 1161 struct icmp6_nodeinfo *ni6, *nni6; 1162 struct mbuf *n = NULL; 1163 u_int16_t qtype; 1164 int subjlen; 1165 int replylen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo); 1166 struct ni_reply_fqdn *fqdn; 1167 int addrs; /* for NI_QTYPE_NODEADDR */ 1168 struct ifnet *ifp = NULL; /* for NI_QTYPE_NODEADDR */ 1169 struct in6_addr in6_subj; /* subject address */ 1170 struct ip6_hdr *ip6; 1171 int oldfqdn = 0; /* if 1, return pascal string (03 draft) */ 1172 char *subj = NULL; 1173 struct in6_ifaddr *ia6 = NULL; 1174 1175 ip6 = mtod(m, struct ip6_hdr *); 1176#ifndef PULLDOWN_TEST 1177 ni6 = (struct icmp6_nodeinfo *)(mtod(m, caddr_t) + off); 1178#else 1179 IP6_EXTHDR_GET(ni6, struct icmp6_nodeinfo *, m, off, sizeof(*ni6)); 1180 if (ni6 == NULL) { 1181 /* m is already reclaimed */ 1182 return (NULL); 1183 } 1184#endif 1185 1186 /* 1187 * Validate IPv6 destination address. 1188 * 1189 * The Responder must discard the Query without further processing 1190 * unless it is one of the Responder's unicast or anycast addresses, or 1191 * a link-local scope multicast address which the Responder has joined. 1192 * [icmp-name-lookups-08, Section 4.] 1193 */ 1194 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 1195 if (!IN6_IS_ADDR_MC_LINKLOCAL(&ip6->ip6_dst)) 1196 goto bad; 1197 /* else it's a link-local multicast, fine */ 1198 } else { /* unicast or anycast */ 1199 if ((ia6 = ip6_getdstifaddr(m)) == NULL) 1200 goto bad; /* XXX impossible */ 1201 1202 if ((ia6->ia6_flags & IN6_IFF_TEMPORARY) && 1203 !(icmp6_nodeinfo & 4)) { 1204 nd6log((LOG_DEBUG, "ni6_input: ignore node info to " 1205 "a temporary address in %s:%d", 1206 __FILE__, __LINE__)); 1207 goto bad; 1208 } 1209 } 1210 1211 /* validate query Subject field. */ 1212 qtype = ntohs(ni6->ni_qtype); 1213 subjlen = m->m_pkthdr.len - off - sizeof(struct icmp6_nodeinfo); 1214 switch (qtype) { 1215 case NI_QTYPE_NOOP: 1216 case NI_QTYPE_SUPTYPES: 1217 /* 07 draft */ 1218 if (ni6->ni_code == ICMP6_NI_SUBJ_FQDN && subjlen == 0) 1219 break; 1220 /* FALLTHROUGH */ 1221 case NI_QTYPE_FQDN: 1222 case NI_QTYPE_NODEADDR: 1223 case NI_QTYPE_IPV4ADDR: 1224 switch (ni6->ni_code) { 1225 case ICMP6_NI_SUBJ_IPV6: 1226#if ICMP6_NI_SUBJ_IPV6 != 0 1227 case 0: 1228#endif 1229 /* 1230 * backward compatibility - try to accept 03 draft 1231 * format, where no Subject is present. 1232 */ 1233 if (qtype == NI_QTYPE_FQDN && ni6->ni_code == 0 && 1234 subjlen == 0) { 1235 oldfqdn++; 1236 break; 1237 } 1238#if ICMP6_NI_SUBJ_IPV6 != 0 1239 if (ni6->ni_code != ICMP6_NI_SUBJ_IPV6) 1240 goto bad; 1241#endif 1242 1243 if (subjlen != sizeof(struct in6_addr)) 1244 goto bad; 1245 1246 /* 1247 * Validate Subject address. 1248 * 1249 * Not sure what exactly "address belongs to the node" 1250 * means in the spec, is it just unicast, or what? 1251 * 1252 * At this moment we consider Subject address as 1253 * "belong to the node" if the Subject address equals 1254 * to the IPv6 destination address; validation for 1255 * IPv6 destination address should have done enough 1256 * check for us. 1257 * 1258 * We do not do proxy at this moment. 1259 */ 1260 /* m_pulldown instead of copy? */ 1261 m_copydata(m, off + sizeof(struct icmp6_nodeinfo), 1262 subjlen, (caddr_t)&in6_subj); 1263 if (in6_setscope(&in6_subj, m->m_pkthdr.rcvif, NULL)) 1264 goto bad; 1265 1266 subj = (char *)&in6_subj; 1267 if (IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, &in6_subj)) 1268 break; 1269 1270 /* 1271 * XXX if we are to allow other cases, we should really 1272 * be careful about scope here. 1273 * basically, we should disallow queries toward IPv6 1274 * destination X with subject Y, 1275 * if scope(X) > scope(Y). 1276 * if we allow scope(X) > scope(Y), it will result in 1277 * information leakage across scope boundary. 1278 */ 1279 goto bad; 1280 1281 case ICMP6_NI_SUBJ_FQDN: 1282 /* 1283 * Validate Subject name with gethostname(3). 1284 * 1285 * The behavior may need some debate, since: 1286 * - we are not sure if the node has FQDN as 1287 * hostname (returned by gethostname(3)). 1288 * - the code does wildcard match for truncated names. 1289 * however, we are not sure if we want to perform 1290 * wildcard match, if gethostname(3) side has 1291 * truncated hostname. 1292 */ 1293 n = ni6_nametodns(hostname, hostnamelen, 0); 1294 if (!n || n->m_next || n->m_len == 0) 1295 goto bad; 1296 IP6_EXTHDR_GET(subj, char *, m, 1297 off + sizeof(struct icmp6_nodeinfo), subjlen); 1298 if (subj == NULL) 1299 goto bad; 1300 if (!ni6_dnsmatch(subj, subjlen, mtod(n, const char *), 1301 n->m_len)) { 1302 goto bad; 1303 } 1304 m_freem(n); 1305 n = NULL; 1306 break; 1307 1308 case ICMP6_NI_SUBJ_IPV4: /* XXX: to be implemented? */ 1309 default: 1310 goto bad; 1311 } 1312 break; 1313 } 1314 1315 /* refuse based on configuration. XXX ICMP6_NI_REFUSED? */ 1316 switch (qtype) { 1317 case NI_QTYPE_FQDN: 1318 if ((icmp6_nodeinfo & 1) == 0) 1319 goto bad; 1320 break; 1321 case NI_QTYPE_NODEADDR: 1322 case NI_QTYPE_IPV4ADDR: 1323 if ((icmp6_nodeinfo & 2) == 0) 1324 goto bad; 1325 break; 1326 } 1327 1328 /* guess reply length */ 1329 switch (qtype) { 1330 case NI_QTYPE_NOOP: 1331 break; /* no reply data */ 1332 case NI_QTYPE_SUPTYPES: 1333 replylen += sizeof(u_int32_t); 1334 break; 1335 case NI_QTYPE_FQDN: 1336 /* XXX will append an mbuf */ 1337 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1338 break; 1339 case NI_QTYPE_NODEADDR: 1340 addrs = ni6_addrs(ni6, m, &ifp, (struct in6_addr *)subj); 1341 if ((replylen += addrs * (sizeof(struct in6_addr) + 1342 sizeof(u_int32_t))) > MCLBYTES) 1343 replylen = MCLBYTES; /* XXX: will truncate pkt later */ 1344 break; 1345 case NI_QTYPE_IPV4ADDR: 1346 /* unsupported - should respond with unknown Qtype? */ 1347 break; 1348 default: 1349 /* 1350 * XXX: We must return a reply with the ICMP6 code 1351 * `unknown Qtype' in this case. However we regard the case 1352 * as an FQDN query for backward compatibility. 1353 * Older versions set a random value to this field, 1354 * so it rarely varies in the defined qtypes. 1355 * But the mechanism is not reliable... 1356 * maybe we should obsolete older versions. 1357 */ 1358 qtype = NI_QTYPE_FQDN; 1359 /* XXX will append an mbuf */ 1360 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1361 oldfqdn++; 1362 break; 1363 } 1364 1365 /* allocate an mbuf to reply. */ 1366 MGETHDR(n, M_DONTWAIT, m->m_type); 1367 if (n == NULL) { 1368 m_freem(m); 1369 return (NULL); 1370 } 1371 M_MOVE_PKTHDR(n, m); /* just for recvif */ 1372 if (replylen > MHLEN) { 1373 if (replylen > MCLBYTES) { 1374 /* 1375 * XXX: should we try to allocate more? But MCLBYTES 1376 * is probably much larger than IPV6_MMTU... 1377 */ 1378 goto bad; 1379 } 1380 MCLGET(n, M_DONTWAIT); 1381 if ((n->m_flags & M_EXT) == 0) { 1382 goto bad; 1383 } 1384 } 1385 n->m_pkthdr.len = n->m_len = replylen; 1386 1387 /* copy mbuf header and IPv6 + Node Information base headers */ 1388 bcopy(mtod(m, caddr_t), mtod(n, caddr_t), sizeof(struct ip6_hdr)); 1389 nni6 = (struct icmp6_nodeinfo *)(mtod(n, struct ip6_hdr *) + 1); 1390 bcopy((caddr_t)ni6, (caddr_t)nni6, sizeof(struct icmp6_nodeinfo)); 1391 1392 /* qtype dependent procedure */ 1393 switch (qtype) { 1394 case NI_QTYPE_NOOP: 1395 nni6->ni_code = ICMP6_NI_SUCCESS; 1396 nni6->ni_flags = 0; 1397 break; 1398 case NI_QTYPE_SUPTYPES: 1399 { 1400 u_int32_t v; 1401 nni6->ni_code = ICMP6_NI_SUCCESS; 1402 nni6->ni_flags = htons(0x0000); /* raw bitmap */ 1403 /* supports NOOP, SUPTYPES, FQDN, and NODEADDR */ 1404 v = (u_int32_t)htonl(0x0000000f); 1405 bcopy(&v, nni6 + 1, sizeof(u_int32_t)); 1406 break; 1407 } 1408 case NI_QTYPE_FQDN: 1409 nni6->ni_code = ICMP6_NI_SUCCESS; 1410 fqdn = (struct ni_reply_fqdn *)(mtod(n, caddr_t) + 1411 sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo)); 1412 nni6->ni_flags = 0; /* XXX: meaningless TTL */ 1413 fqdn->ni_fqdn_ttl = 0; /* ditto. */ 1414 /* 1415 * XXX do we really have FQDN in variable "hostname"? 1416 */ 1417 n->m_next = ni6_nametodns(hostname, hostnamelen, oldfqdn); 1418 if (n->m_next == NULL) 1419 goto bad; 1420 /* XXX we assume that n->m_next is not a chain */ 1421 if (n->m_next->m_next != NULL) 1422 goto bad; 1423 n->m_pkthdr.len += n->m_next->m_len; 1424 break; 1425 case NI_QTYPE_NODEADDR: 1426 { 1427 int lenlim, copied; 1428 1429 nni6->ni_code = ICMP6_NI_SUCCESS; 1430 n->m_pkthdr.len = n->m_len = 1431 sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo); 1432 lenlim = M_TRAILINGSPACE(n); 1433 copied = ni6_store_addrs(ni6, nni6, ifp, lenlim); 1434 /* XXX: reset mbuf length */ 1435 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) + 1436 sizeof(struct icmp6_nodeinfo) + copied; 1437 break; 1438 } 1439 default: 1440 break; /* XXX impossible! */ 1441 } 1442 1443 nni6->ni_type = ICMP6_NI_REPLY; 1444 m_freem(m); 1445 return (n); 1446 1447 bad: 1448 m_freem(m); 1449 if (n) 1450 m_freem(n); 1451 return (NULL); 1452} 1453#undef hostnamelen 1454 1455/* 1456 * make a mbuf with DNS-encoded string. no compression support. 1457 * 1458 * XXX names with less than 2 dots (like "foo" or "foo.section") will be 1459 * treated as truncated name (two \0 at the end). this is a wild guess. 1460 */ 1461static struct mbuf * 1462ni6_nametodns(name, namelen, old) 1463 const char *name; 1464 int namelen; 1465 int old; /* return pascal string if non-zero */ 1466{ 1467 struct mbuf *m; 1468 char *cp, *ep; 1469 const char *p, *q; 1470 int i, len, nterm; 1471 1472 if (old) 1473 len = namelen + 1; 1474 else 1475 len = MCLBYTES; 1476 1477 /* because MAXHOSTNAMELEN is usually 256, we use cluster mbuf */ 1478 MGET(m, M_DONTWAIT, MT_DATA); 1479 if (m && len > MLEN) { 1480 MCLGET(m, M_DONTWAIT); 1481 if ((m->m_flags & M_EXT) == 0) 1482 goto fail; 1483 } 1484 if (!m) 1485 goto fail; 1486 m->m_next = NULL; 1487 1488 if (old) { 1489 m->m_len = len; 1490 *mtod(m, char *) = namelen; 1491 bcopy(name, mtod(m, char *) + 1, namelen); 1492 return m; 1493 } else { 1494 m->m_len = 0; 1495 cp = mtod(m, char *); 1496 ep = mtod(m, char *) + M_TRAILINGSPACE(m); 1497 1498 /* if not certain about my name, return empty buffer */ 1499 if (namelen == 0) 1500 return m; 1501 1502 /* 1503 * guess if it looks like shortened hostname, or FQDN. 1504 * shortened hostname needs two trailing "\0". 1505 */ 1506 i = 0; 1507 for (p = name; p < name + namelen; p++) { 1508 if (*p && *p == '.') 1509 i++; 1510 } 1511 if (i < 2) 1512 nterm = 2; 1513 else 1514 nterm = 1; 1515 1516 p = name; 1517 while (cp < ep && p < name + namelen) { 1518 i = 0; 1519 for (q = p; q < name + namelen && *q && *q != '.'; q++) 1520 i++; 1521 /* result does not fit into mbuf */ 1522 if (cp + i + 1 >= ep) 1523 goto fail; 1524 /* 1525 * DNS label length restriction, RFC1035 page 8. 1526 * "i == 0" case is included here to avoid returning 1527 * 0-length label on "foo..bar". 1528 */ 1529 if (i <= 0 || i >= 64) 1530 goto fail; 1531 *cp++ = i; 1532 bcopy(p, cp, i); 1533 cp += i; 1534 p = q; 1535 if (p < name + namelen && *p == '.') 1536 p++; 1537 } 1538 /* termination */ 1539 if (cp + nterm >= ep) 1540 goto fail; 1541 while (nterm-- > 0) 1542 *cp++ = '\0'; 1543 m->m_len = cp - mtod(m, char *); 1544 return m; 1545 } 1546 1547 panic("should not reach here"); 1548 /* NOTREACHED */ 1549 1550 fail: 1551 if (m) 1552 m_freem(m); 1553 return NULL; 1554} 1555 1556/* 1557 * check if two DNS-encoded string matches. takes care of truncated 1558 * form (with \0\0 at the end). no compression support. 1559 * XXX upper/lowercase match (see RFC2065) 1560 */ 1561static int 1562ni6_dnsmatch(a, alen, b, blen) 1563 const char *a; 1564 int alen; 1565 const char *b; 1566 int blen; 1567{ 1568 const char *a0, *b0; 1569 int l; 1570 1571 /* simplest case - need validation? */ 1572 if (alen == blen && bcmp(a, b, alen) == 0) 1573 return 1; 1574 1575 a0 = a; 1576 b0 = b; 1577 1578 /* termination is mandatory */ 1579 if (alen < 2 || blen < 2) 1580 return 0; 1581 if (a0[alen - 1] != '\0' || b0[blen - 1] != '\0') 1582 return 0; 1583 alen--; 1584 blen--; 1585 1586 while (a - a0 < alen && b - b0 < blen) { 1587 if (a - a0 + 1 > alen || b - b0 + 1 > blen) 1588 return 0; 1589 1590 if ((signed char)a[0] < 0 || (signed char)b[0] < 0) 1591 return 0; 1592 /* we don't support compression yet */ 1593 if (a[0] >= 64 || b[0] >= 64) 1594 return 0; 1595 1596 /* truncated case */ 1597 if (a[0] == 0 && a - a0 == alen - 1) 1598 return 1; 1599 if (b[0] == 0 && b - b0 == blen - 1) 1600 return 1; 1601 if (a[0] == 0 || b[0] == 0) 1602 return 0; 1603 1604 if (a[0] != b[0]) 1605 return 0; 1606 l = a[0]; 1607 if (a - a0 + 1 + l > alen || b - b0 + 1 + l > blen) 1608 return 0; 1609 if (bcmp(a + 1, b + 1, l) != 0) 1610 return 0; 1611 1612 a += 1 + l; 1613 b += 1 + l; 1614 } 1615 1616 if (a - a0 == alen && b - b0 == blen) 1617 return 1; 1618 else 1619 return 0; 1620} 1621 1622/* 1623 * calculate the number of addresses to be returned in the node info reply. 1624 */ 1625static int 1626ni6_addrs(ni6, m, ifpp, subj) 1627 struct icmp6_nodeinfo *ni6; 1628 struct mbuf *m; 1629 struct ifnet **ifpp; 1630 struct in6_addr *subj; 1631{ 1632 struct ifnet *ifp; 1633 struct in6_ifaddr *ifa6; 1634 struct ifaddr *ifa; 1635 int addrs = 0, addrsofif, iffound = 0; 1636 int niflags = ni6->ni_flags; 1637 1638 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0) { 1639 switch (ni6->ni_code) { 1640 case ICMP6_NI_SUBJ_IPV6: 1641 if (subj == NULL) /* must be impossible... */ 1642 return (0); 1643 break; 1644 default: 1645 /* 1646 * XXX: we only support IPv6 subject address for 1647 * this Qtype. 1648 */ 1649 return (0); 1650 } 1651 } 1652 1653 IFNET_RLOCK(); 1654 for (ifp = TAILQ_FIRST(&ifnet); ifp; ifp = TAILQ_NEXT(ifp, if_list)) { 1655 addrsofif = 0; 1656 TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list) { 1657 if (ifa->ifa_addr->sa_family != AF_INET6) 1658 continue; 1659 ifa6 = (struct in6_ifaddr *)ifa; 1660 1661 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0 && 1662 IN6_ARE_ADDR_EQUAL(subj, &ifa6->ia_addr.sin6_addr)) 1663 iffound = 1; 1664 1665 /* 1666 * IPv4-mapped addresses can only be returned by a 1667 * Node Information proxy, since they represent 1668 * addresses of IPv4-only nodes, which perforce do 1669 * not implement this protocol. 1670 * [icmp-name-lookups-07, Section 5.4] 1671 * So we don't support NI_NODEADDR_FLAG_COMPAT in 1672 * this function at this moment. 1673 */ 1674 1675 /* What do we have to do about ::1? */ 1676 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1677 case IPV6_ADDR_SCOPE_LINKLOCAL: 1678 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0) 1679 continue; 1680 break; 1681 case IPV6_ADDR_SCOPE_SITELOCAL: 1682 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0) 1683 continue; 1684 break; 1685 case IPV6_ADDR_SCOPE_GLOBAL: 1686 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0) 1687 continue; 1688 break; 1689 default: 1690 continue; 1691 } 1692 1693 /* 1694 * check if anycast is okay. 1695 * XXX: just experimental. not in the spec. 1696 */ 1697 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 && 1698 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0) 1699 continue; /* we need only unicast addresses */ 1700 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 1701 (icmp6_nodeinfo & 4) == 0) { 1702 continue; 1703 } 1704 addrsofif++; /* count the address */ 1705 } 1706 if (iffound) { 1707 *ifpp = ifp; 1708 IFNET_RUNLOCK(); 1709 return (addrsofif); 1710 } 1711 1712 addrs += addrsofif; 1713 } 1714 IFNET_RUNLOCK(); 1715 1716 return (addrs); 1717} 1718 1719static int 1720ni6_store_addrs(ni6, nni6, ifp0, resid) 1721 struct icmp6_nodeinfo *ni6, *nni6; 1722 struct ifnet *ifp0; 1723 int resid; 1724{ 1725 struct ifnet *ifp = ifp0 ? ifp0 : TAILQ_FIRST(&ifnet); 1726 struct in6_ifaddr *ifa6; 1727 struct ifaddr *ifa; 1728 struct ifnet *ifp_dep = NULL; 1729 int copied = 0, allow_deprecated = 0; 1730 u_char *cp = (u_char *)(nni6 + 1); 1731 int niflags = ni6->ni_flags; 1732 u_int32_t ltime; 1733 1734 if (ifp0 == NULL && !(niflags & NI_NODEADDR_FLAG_ALL)) 1735 return (0); /* needless to copy */ 1736 1737 IFNET_RLOCK(); 1738 again: 1739 1740 for (; ifp; ifp = TAILQ_NEXT(ifp, if_list)) { 1741 for (ifa = ifp->if_addrlist.tqh_first; ifa; 1742 ifa = ifa->ifa_list.tqe_next) { 1743 if (ifa->ifa_addr->sa_family != AF_INET6) 1744 continue; 1745 ifa6 = (struct in6_ifaddr *)ifa; 1746 1747 if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) != 0 && 1748 allow_deprecated == 0) { 1749 /* 1750 * prefererred address should be put before 1751 * deprecated addresses. 1752 */ 1753 1754 /* record the interface for later search */ 1755 if (ifp_dep == NULL) 1756 ifp_dep = ifp; 1757 1758 continue; 1759 } else if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) == 0 && 1760 allow_deprecated != 0) 1761 continue; /* we now collect deprecated addrs */ 1762 1763 /* What do we have to do about ::1? */ 1764 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1765 case IPV6_ADDR_SCOPE_LINKLOCAL: 1766 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0) 1767 continue; 1768 break; 1769 case IPV6_ADDR_SCOPE_SITELOCAL: 1770 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0) 1771 continue; 1772 break; 1773 case IPV6_ADDR_SCOPE_GLOBAL: 1774 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0) 1775 continue; 1776 break; 1777 default: 1778 continue; 1779 } 1780 1781 /* 1782 * check if anycast is okay. 1783 * XXX: just experimental. not in the spec. 1784 */ 1785 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 && 1786 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0) 1787 continue; 1788 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 1789 (icmp6_nodeinfo & 4) == 0) { 1790 continue; 1791 } 1792 1793 /* now we can copy the address */ 1794 if (resid < sizeof(struct in6_addr) + 1795 sizeof(u_int32_t)) { 1796 /* 1797 * We give up much more copy. 1798 * Set the truncate flag and return. 1799 */ 1800 nni6->ni_flags |= NI_NODEADDR_FLAG_TRUNCATE; 1801 IFNET_RUNLOCK(); 1802 return (copied); 1803 } 1804 1805 /* 1806 * Set the TTL of the address. 1807 * The TTL value should be one of the following 1808 * according to the specification: 1809 * 1810 * 1. The remaining lifetime of a DHCP lease on the 1811 * address, or 1812 * 2. The remaining Valid Lifetime of a prefix from 1813 * which the address was derived through Stateless 1814 * Autoconfiguration. 1815 * 1816 * Note that we currently do not support stateful 1817 * address configuration by DHCPv6, so the former 1818 * case can't happen. 1819 */ 1820 if (ifa6->ia6_lifetime.ia6t_expire == 0) 1821 ltime = ND6_INFINITE_LIFETIME; 1822 else { 1823 if (ifa6->ia6_lifetime.ia6t_expire > 1824 time_second) 1825 ltime = htonl(ifa6->ia6_lifetime.ia6t_expire - time_second); 1826 else 1827 ltime = 0; 1828 } 1829 1830 bcopy(<ime, cp, sizeof(u_int32_t)); 1831 cp += sizeof(u_int32_t); 1832 1833 /* copy the address itself */ 1834 bcopy(&ifa6->ia_addr.sin6_addr, cp, 1835 sizeof(struct in6_addr)); 1836 in6_clearscope((struct in6_addr *)cp); /* XXX */ 1837 cp += sizeof(struct in6_addr); 1838 1839 resid -= (sizeof(struct in6_addr) + sizeof(u_int32_t)); 1840 copied += (sizeof(struct in6_addr) + sizeof(u_int32_t)); 1841 } 1842 if (ifp0) /* we need search only on the specified IF */ 1843 break; 1844 } 1845 1846 if (allow_deprecated == 0 && ifp_dep != NULL) { 1847 ifp = ifp_dep; 1848 allow_deprecated = 1; 1849 1850 goto again; 1851 } 1852 1853 IFNET_RUNLOCK(); 1854 1855 return (copied); 1856} 1857 1858/* 1859 * XXX almost dup'ed code with rip6_input. 1860 */ 1861static int 1862icmp6_rip6_input(mp, off) 1863 struct mbuf **mp; 1864 int off; 1865{ 1866 struct mbuf *m = *mp; 1867 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1868 struct in6pcb *in6p; 1869 struct in6pcb *last = NULL; 1870 struct sockaddr_in6 fromsa; 1871 struct icmp6_hdr *icmp6; 1872 struct mbuf *opts = NULL; 1873 1874#ifndef PULLDOWN_TEST 1875 /* this is assumed to be safe. */ 1876 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off); 1877#else 1878 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 1879 if (icmp6 == NULL) { 1880 /* m is already reclaimed */ 1881 return (IPPROTO_DONE); 1882 } 1883#endif 1884 1885 /* 1886 * XXX: the address may have embedded scope zone ID, which should be 1887 * hidden from applications. 1888 */ 1889 bzero(&fromsa, sizeof(fromsa)); 1890 fromsa.sin6_family = AF_INET6; 1891 fromsa.sin6_len = sizeof(struct sockaddr_in6); 1892 fromsa.sin6_addr = ip6->ip6_src; 1893 if (sa6_recoverscope(&fromsa)) { 1894 m_freem(m); 1895 return (IPPROTO_DONE); 1896 } 1897 1898 INP_INFO_RLOCK(&ripcbinfo); 1899 LIST_FOREACH(in6p, &ripcb, inp_list) { 1900 INP_LOCK(in6p); 1901 if ((in6p->inp_vflag & INP_IPV6) == 0) { 1902 docontinue: 1903 INP_UNLOCK(in6p); 1904 continue; 1905 } 1906 if (in6p->in6p_ip6_nxt != IPPROTO_ICMPV6) 1907 goto docontinue; 1908 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr) && 1909 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr, &ip6->ip6_dst)) 1910 goto docontinue; 1911 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr) && 1912 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr, &ip6->ip6_src)) 1913 goto docontinue; 1914 if (in6p->in6p_icmp6filt 1915 && ICMP6_FILTER_WILLBLOCK(icmp6->icmp6_type, 1916 in6p->in6p_icmp6filt)) 1917 goto docontinue; 1918 if (last) { 1919 struct mbuf *n = NULL; 1920 1921 /* 1922 * Recent network drivers tend to allocate a single 1923 * mbuf cluster, rather than to make a couple of 1924 * mbufs without clusters. Also, since the IPv6 code 1925 * path tries to avoid m_pullup(), it is highly 1926 * probable that we still have an mbuf cluster here 1927 * even though the necessary length can be stored in an 1928 * mbuf's internal buffer. 1929 * Meanwhile, the default size of the receive socket 1930 * buffer for raw sockets is not so large. This means 1931 * the possibility of packet loss is relatively higher 1932 * than before. To avoid this scenario, we copy the 1933 * received data to a separate mbuf that does not use 1934 * a cluster, if possible. 1935 * XXX: it is better to copy the data after stripping 1936 * intermediate headers. 1937 */ 1938 if ((m->m_flags & M_EXT) && m->m_next == NULL && 1939 m->m_len <= MHLEN) { 1940 MGET(n, M_DONTWAIT, m->m_type); 1941 if (n != NULL) { 1942 if (m_dup_pkthdr(n, m, M_NOWAIT)) { 1943 bcopy(m->m_data, n->m_data, 1944 m->m_len); 1945 n->m_len = m->m_len; 1946 } else { 1947 m_free(n); 1948 n = NULL; 1949 } 1950 } 1951 } 1952 if (n != NULL || 1953 (n = m_copy(m, 0, (int)M_COPYALL)) != NULL) { 1954 if (last->in6p_flags & IN6P_CONTROLOPTS) 1955 ip6_savecontrol(last, n, &opts); 1956 /* strip intermediate headers */ 1957 m_adj(n, off); 1958 SOCKBUF_LOCK(&last->in6p_socket->so_rcv); 1959 if (sbappendaddr_locked( 1960 &last->in6p_socket->so_rcv, 1961 (struct sockaddr *)&fromsa, n, opts) 1962 == 0) { 1963 /* should notify about lost packet */ 1964 m_freem(n); 1965 if (opts) { 1966 m_freem(opts); 1967 } 1968 SOCKBUF_UNLOCK( 1969 &last->in6p_socket->so_rcv); 1970 } else 1971 sorwakeup_locked(last->in6p_socket); 1972 opts = NULL; 1973 } 1974 INP_UNLOCK(last); 1975 } 1976 last = in6p; 1977 } 1978 if (last) { 1979 if (last->in6p_flags & IN6P_CONTROLOPTS) 1980 ip6_savecontrol(last, m, &opts); 1981 /* strip intermediate headers */ 1982 m_adj(m, off); 1983 1984 /* avoid using mbuf clusters if possible (see above) */ 1985 if ((m->m_flags & M_EXT) && m->m_next == NULL && 1986 m->m_len <= MHLEN) { 1987 struct mbuf *n; 1988 1989 MGET(n, M_DONTWAIT, m->m_type); 1990 if (n != NULL) { 1991 if (m_dup_pkthdr(n, m, M_NOWAIT)) { 1992 bcopy(m->m_data, n->m_data, m->m_len); 1993 n->m_len = m->m_len; 1994 1995 m_freem(m); 1996 m = n; 1997 } else { 1998 m_freem(n); 1999 n = NULL; 2000 } 2001 } 2002 } 2003 SOCKBUF_LOCK(&last->in6p_socket->so_rcv); 2004 if (sbappendaddr_locked(&last->in6p_socket->so_rcv, 2005 (struct sockaddr *)&fromsa, m, opts) == 0) { 2006 m_freem(m); 2007 if (opts) 2008 m_freem(opts); 2009 SOCKBUF_UNLOCK(&last->in6p_socket->so_rcv); 2010 } else 2011 sorwakeup_locked(last->in6p_socket); 2012 INP_UNLOCK(last); 2013 } else { 2014 m_freem(m); 2015 ip6stat.ip6s_delivered--; 2016 } 2017 INP_INFO_RUNLOCK(&ripcbinfo); 2018 return IPPROTO_DONE; 2019} 2020 2021/* 2022 * Reflect the ip6 packet back to the source. 2023 * OFF points to the icmp6 header, counted from the top of the mbuf. 2024 */ 2025void 2026icmp6_reflect(m, off) 2027 struct mbuf *m; 2028 size_t off; 2029{ 2030 struct ip6_hdr *ip6; 2031 struct icmp6_hdr *icmp6; 2032 struct in6_ifaddr *ia; 2033 int plen; 2034 int type, code; 2035 struct ifnet *outif = NULL; 2036 struct in6_addr origdst, *src = NULL; 2037 2038 /* too short to reflect */ 2039 if (off < sizeof(struct ip6_hdr)) { 2040 nd6log((LOG_DEBUG, 2041 "sanity fail: off=%lx, sizeof(ip6)=%lx in %s:%d\n", 2042 (u_long)off, (u_long)sizeof(struct ip6_hdr), 2043 __FILE__, __LINE__)); 2044 goto bad; 2045 } 2046 2047 /* 2048 * If there are extra headers between IPv6 and ICMPv6, strip 2049 * off that header first. 2050 */ 2051#ifdef DIAGNOSTIC 2052 if (sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) > MHLEN) 2053 panic("assumption failed in icmp6_reflect"); 2054#endif 2055 if (off > sizeof(struct ip6_hdr)) { 2056 size_t l; 2057 struct ip6_hdr nip6; 2058 2059 l = off - sizeof(struct ip6_hdr); 2060 m_copydata(m, 0, sizeof(nip6), (caddr_t)&nip6); 2061 m_adj(m, l); 2062 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 2063 if (m->m_len < l) { 2064 if ((m = m_pullup(m, l)) == NULL) 2065 return; 2066 } 2067 bcopy((caddr_t)&nip6, mtod(m, caddr_t), sizeof(nip6)); 2068 } else /* off == sizeof(struct ip6_hdr) */ { 2069 size_t l; 2070 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 2071 if (m->m_len < l) { 2072 if ((m = m_pullup(m, l)) == NULL) 2073 return; 2074 } 2075 } 2076 plen = m->m_pkthdr.len - sizeof(struct ip6_hdr); 2077 ip6 = mtod(m, struct ip6_hdr *); 2078 ip6->ip6_nxt = IPPROTO_ICMPV6; 2079 icmp6 = (struct icmp6_hdr *)(ip6 + 1); 2080 type = icmp6->icmp6_type; /* keep type for statistics */ 2081 code = icmp6->icmp6_code; /* ditto. */ 2082 2083 origdst = ip6->ip6_dst; 2084 /* 2085 * ip6_input() drops a packet if its src is multicast. 2086 * So, the src is never multicast. 2087 */ 2088 ip6->ip6_dst = ip6->ip6_src; 2089 2090 /* 2091 * If the incoming packet was addressed directly to us (i.e. unicast), 2092 * use dst as the src for the reply. 2093 * The IN6_IFF_NOTREADY case should be VERY rare, but is possible 2094 * (for example) when we encounter an error while forwarding procedure 2095 * destined to a duplicated address of ours. 2096 * Note that ip6_getdstifaddr() may fail if we are in an error handling 2097 * procedure of an outgoing packet of our own, in which case we need 2098 * to search in the ifaddr list. 2099 */ 2100 if (!IN6_IS_ADDR_MULTICAST(&origdst)) { 2101 if ((ia = ip6_getdstifaddr(m))) { 2102 if (!(ia->ia6_flags & 2103 (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY))) 2104 src = &ia->ia_addr.sin6_addr; 2105 } else { 2106 struct sockaddr_in6 d; 2107 2108 bzero(&d, sizeof(d)); 2109 d.sin6_family = AF_INET6; 2110 d.sin6_len = sizeof(d); 2111 d.sin6_addr = origdst; 2112 ia = (struct in6_ifaddr *) 2113 ifa_ifwithaddr((struct sockaddr *)&d); 2114 if (ia && 2115 !(ia->ia6_flags & 2116 (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY))) { 2117 src = &ia->ia_addr.sin6_addr; 2118 } 2119 } 2120 } 2121 2122 if (src == NULL) { 2123 int e; 2124 struct sockaddr_in6 sin6; 2125 struct route_in6 ro; 2126 2127 /* 2128 * This case matches to multicasts, our anycast, or unicasts 2129 * that we do not own. Select a source address based on the 2130 * source address of the erroneous packet. 2131 */ 2132 bzero(&sin6, sizeof(sin6)); 2133 sin6.sin6_family = AF_INET6; 2134 sin6.sin6_len = sizeof(sin6); 2135 sin6.sin6_addr = ip6->ip6_dst; /* zone ID should be embedded */ 2136 2137 bzero(&ro, sizeof(ro)); 2138 src = in6_selectsrc(&sin6, NULL, NULL, &ro, NULL, &outif, &e); 2139 if (ro.ro_rt) 2140 RTFREE(ro.ro_rt); /* XXX: we could use this */ 2141 if (src == NULL) { 2142 char ip6buf[INET6_ADDRSTRLEN]; 2143 nd6log((LOG_DEBUG, 2144 "icmp6_reflect: source can't be determined: " 2145 "dst=%s, error=%d\n", 2146 ip6_sprintf(ip6buf, &sin6.sin6_addr), e)); 2147 goto bad; 2148 } 2149 } 2150 2151 ip6->ip6_src = *src; 2152 ip6->ip6_flow = 0; 2153 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2154 ip6->ip6_vfc |= IPV6_VERSION; 2155 ip6->ip6_nxt = IPPROTO_ICMPV6; 2156 if (outif) 2157 ip6->ip6_hlim = ND_IFINFO(outif)->chlim; 2158 else if (m->m_pkthdr.rcvif) { 2159 /* XXX: This may not be the outgoing interface */ 2160 ip6->ip6_hlim = ND_IFINFO(m->m_pkthdr.rcvif)->chlim; 2161 } else 2162 ip6->ip6_hlim = ip6_defhlim; 2163 2164 icmp6->icmp6_cksum = 0; 2165 icmp6->icmp6_cksum = in6_cksum(m, IPPROTO_ICMPV6, 2166 sizeof(struct ip6_hdr), plen); 2167 2168 /* 2169 * XXX option handling 2170 */ 2171 2172 m->m_flags &= ~(M_BCAST|M_MCAST); 2173 2174 ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL); 2175 if (outif) 2176 icmp6_ifoutstat_inc(outif, type, code); 2177 2178 return; 2179 2180 bad: 2181 m_freem(m); 2182 return; 2183} 2184 2185void 2186icmp6_fasttimo() 2187{ 2188 2189 return; 2190} 2191 2192static const char * 2193icmp6_redirect_diag(src6, dst6, tgt6) 2194 struct in6_addr *src6; 2195 struct in6_addr *dst6; 2196 struct in6_addr *tgt6; 2197{ 2198 static char buf[1024]; 2199 char ip6bufs[INET6_ADDRSTRLEN]; 2200 char ip6bufd[INET6_ADDRSTRLEN]; 2201 char ip6buft[INET6_ADDRSTRLEN]; 2202 snprintf(buf, sizeof(buf), "(src=%s dst=%s tgt=%s)", 2203 ip6_sprintf(ip6bufs, src6), ip6_sprintf(ip6bufd, dst6), 2204 ip6_sprintf(ip6buft, tgt6)); 2205 return buf; 2206} 2207 2208void 2209icmp6_redirect_input(m, off) 2210 struct mbuf *m; 2211 int off; 2212{ 2213 struct ifnet *ifp = m->m_pkthdr.rcvif; 2214 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 2215 struct nd_redirect *nd_rd; 2216 int icmp6len = ntohs(ip6->ip6_plen); 2217 char *lladdr = NULL; 2218 int lladdrlen = 0; 2219 u_char *redirhdr = NULL; 2220 int redirhdrlen = 0; 2221 struct rtentry *rt = NULL; 2222 int is_router; 2223 int is_onlink; 2224 struct in6_addr src6 = ip6->ip6_src; 2225 struct in6_addr redtgt6; 2226 struct in6_addr reddst6; 2227 union nd_opts ndopts; 2228 char ip6buf[INET6_ADDRSTRLEN]; 2229 2230 if (!m || !ifp) 2231 return; 2232 2233 /* XXX if we are router, we don't update route by icmp6 redirect */ 2234 if (ip6_forwarding) 2235 goto freeit; 2236 if (!icmp6_rediraccept) 2237 goto freeit; 2238 2239#ifndef PULLDOWN_TEST 2240 IP6_EXTHDR_CHECK(m, off, icmp6len,); 2241 nd_rd = (struct nd_redirect *)((caddr_t)ip6 + off); 2242#else 2243 IP6_EXTHDR_GET(nd_rd, struct nd_redirect *, m, off, icmp6len); 2244 if (nd_rd == NULL) { 2245 icmp6stat.icp6s_tooshort++; 2246 return; 2247 } 2248#endif 2249 redtgt6 = nd_rd->nd_rd_target; 2250 reddst6 = nd_rd->nd_rd_dst; 2251 2252 if (in6_setscope(&redtgt6, m->m_pkthdr.rcvif, NULL) || 2253 in6_setscope(&reddst6, m->m_pkthdr.rcvif, NULL)) { 2254 goto freeit; 2255 } 2256 2257 /* validation */ 2258 if (!IN6_IS_ADDR_LINKLOCAL(&src6)) { 2259 nd6log((LOG_ERR, 2260 "ICMP6 redirect sent from %s rejected; " 2261 "must be from linklocal\n", 2262 ip6_sprintf(ip6buf, &src6))); 2263 goto bad; 2264 } 2265 if (ip6->ip6_hlim != 255) { 2266 nd6log((LOG_ERR, 2267 "ICMP6 redirect sent from %s rejected; " 2268 "hlim=%d (must be 255)\n", 2269 ip6_sprintf(ip6buf, &src6), ip6->ip6_hlim)); 2270 goto bad; 2271 } 2272 { 2273 /* ip6->ip6_src must be equal to gw for icmp6->icmp6_reddst */ 2274 struct sockaddr_in6 sin6; 2275 struct in6_addr *gw6; 2276 2277 bzero(&sin6, sizeof(sin6)); 2278 sin6.sin6_family = AF_INET6; 2279 sin6.sin6_len = sizeof(struct sockaddr_in6); 2280 bcopy(&reddst6, &sin6.sin6_addr, sizeof(reddst6)); 2281 rt = rtalloc1((struct sockaddr *)&sin6, 0, 0UL); 2282 if (rt) { 2283 if (rt->rt_gateway == NULL || 2284 rt->rt_gateway->sa_family != AF_INET6) { 2285 nd6log((LOG_ERR, 2286 "ICMP6 redirect rejected; no route " 2287 "with inet6 gateway found for redirect dst: %s\n", 2288 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2289 RTFREE_LOCKED(rt); 2290 goto bad; 2291 } 2292 2293 gw6 = &(((struct sockaddr_in6 *)rt->rt_gateway)->sin6_addr); 2294 if (bcmp(&src6, gw6, sizeof(struct in6_addr)) != 0) { 2295 nd6log((LOG_ERR, 2296 "ICMP6 redirect rejected; " 2297 "not equal to gw-for-src=%s (must be same): " 2298 "%s\n", 2299 ip6_sprintf(ip6buf, gw6), 2300 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2301 RTFREE_LOCKED(rt); 2302 goto bad; 2303 } 2304 } else { 2305 nd6log((LOG_ERR, 2306 "ICMP6 redirect rejected; " 2307 "no route found for redirect dst: %s\n", 2308 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2309 goto bad; 2310 } 2311 RTFREE_LOCKED(rt); 2312 rt = NULL; 2313 } 2314 if (IN6_IS_ADDR_MULTICAST(&reddst6)) { 2315 nd6log((LOG_ERR, 2316 "ICMP6 redirect rejected; " 2317 "redirect dst must be unicast: %s\n", 2318 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2319 goto bad; 2320 } 2321 2322 is_router = is_onlink = 0; 2323 if (IN6_IS_ADDR_LINKLOCAL(&redtgt6)) 2324 is_router = 1; /* router case */ 2325 if (bcmp(&redtgt6, &reddst6, sizeof(redtgt6)) == 0) 2326 is_onlink = 1; /* on-link destination case */ 2327 if (!is_router && !is_onlink) { 2328 nd6log((LOG_ERR, 2329 "ICMP6 redirect rejected; " 2330 "neither router case nor onlink case: %s\n", 2331 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2332 goto bad; 2333 } 2334 /* validation passed */ 2335 2336 icmp6len -= sizeof(*nd_rd); 2337 nd6_option_init(nd_rd + 1, icmp6len, &ndopts); 2338 if (nd6_options(&ndopts) < 0) { 2339 nd6log((LOG_INFO, "icmp6_redirect_input: " 2340 "invalid ND option, rejected: %s\n", 2341 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2342 /* nd6_options have incremented stats */ 2343 goto freeit; 2344 } 2345 2346 if (ndopts.nd_opts_tgt_lladdr) { 2347 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 2348 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 2349 } 2350 2351 if (ndopts.nd_opts_rh) { 2352 redirhdrlen = ndopts.nd_opts_rh->nd_opt_rh_len; 2353 redirhdr = (u_char *)(ndopts.nd_opts_rh + 1); /* xxx */ 2354 } 2355 2356 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 2357 nd6log((LOG_INFO, 2358 "icmp6_redirect_input: lladdrlen mismatch for %s " 2359 "(if %d, icmp6 packet %d): %s\n", 2360 ip6_sprintf(ip6buf, &redtgt6), 2361 ifp->if_addrlen, lladdrlen - 2, 2362 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2363 goto bad; 2364 } 2365 2366 /* RFC 2461 8.3 */ 2367 nd6_cache_lladdr(ifp, &redtgt6, lladdr, lladdrlen, ND_REDIRECT, 2368 is_onlink ? ND_REDIRECT_ONLINK : ND_REDIRECT_ROUTER); 2369 2370 if (!is_onlink) { /* better router case. perform rtredirect. */ 2371 /* perform rtredirect */ 2372 struct sockaddr_in6 sdst; 2373 struct sockaddr_in6 sgw; 2374 struct sockaddr_in6 ssrc; 2375 2376 bzero(&sdst, sizeof(sdst)); 2377 bzero(&sgw, sizeof(sgw)); 2378 bzero(&ssrc, sizeof(ssrc)); 2379 sdst.sin6_family = sgw.sin6_family = ssrc.sin6_family = AF_INET6; 2380 sdst.sin6_len = sgw.sin6_len = ssrc.sin6_len = 2381 sizeof(struct sockaddr_in6); 2382 bcopy(&redtgt6, &sgw.sin6_addr, sizeof(struct in6_addr)); 2383 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2384 bcopy(&src6, &ssrc.sin6_addr, sizeof(struct in6_addr)); 2385 rtredirect((struct sockaddr *)&sdst, (struct sockaddr *)&sgw, 2386 (struct sockaddr *)NULL, RTF_GATEWAY | RTF_HOST, 2387 (struct sockaddr *)&ssrc); 2388 } 2389 /* finally update cached route in each socket via pfctlinput */ 2390 { 2391 struct sockaddr_in6 sdst; 2392 2393 bzero(&sdst, sizeof(sdst)); 2394 sdst.sin6_family = AF_INET6; 2395 sdst.sin6_len = sizeof(struct sockaddr_in6); 2396 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2397 pfctlinput(PRC_REDIRECT_HOST, (struct sockaddr *)&sdst); 2398#if defined(IPSEC) || defined(FAST_IPSEC) 2399 key_sa_routechange((struct sockaddr *)&sdst); 2400#endif 2401 } 2402 2403 freeit: 2404 m_freem(m); 2405 return; 2406 2407 bad: 2408 icmp6stat.icp6s_badredirect++; 2409 m_freem(m); 2410} 2411 2412void 2413icmp6_redirect_output(m0, rt) 2414 struct mbuf *m0; 2415 struct rtentry *rt; 2416{ 2417 struct ifnet *ifp; /* my outgoing interface */ 2418 struct in6_addr *ifp_ll6; 2419 struct in6_addr *router_ll6; 2420 struct ip6_hdr *sip6; /* m0 as struct ip6_hdr */ 2421 struct mbuf *m = NULL; /* newly allocated one */ 2422 struct ip6_hdr *ip6; /* m as struct ip6_hdr */ 2423 struct nd_redirect *nd_rd; 2424 size_t maxlen; 2425 u_char *p; 2426 struct ifnet *outif = NULL; 2427 struct sockaddr_in6 src_sa; 2428 2429 icmp6_errcount(&icmp6stat.icp6s_outerrhist, ND_REDIRECT, 0); 2430 2431 /* if we are not router, we don't send icmp6 redirect */ 2432 if (!ip6_forwarding) 2433 goto fail; 2434 2435 /* sanity check */ 2436 if (!m0 || !rt || !(rt->rt_flags & RTF_UP) || !(ifp = rt->rt_ifp)) 2437 goto fail; 2438 2439 /* 2440 * Address check: 2441 * the source address must identify a neighbor, and 2442 * the destination address must not be a multicast address 2443 * [RFC 2461, sec 8.2] 2444 */ 2445 sip6 = mtod(m0, struct ip6_hdr *); 2446 bzero(&src_sa, sizeof(src_sa)); 2447 src_sa.sin6_family = AF_INET6; 2448 src_sa.sin6_len = sizeof(src_sa); 2449 src_sa.sin6_addr = sip6->ip6_src; 2450 if (nd6_is_addr_neighbor(&src_sa, ifp) == 0) 2451 goto fail; 2452 if (IN6_IS_ADDR_MULTICAST(&sip6->ip6_dst)) 2453 goto fail; /* what should we do here? */ 2454 2455 /* rate limit */ 2456 if (icmp6_ratelimit(&sip6->ip6_src, ND_REDIRECT, 0)) 2457 goto fail; 2458 2459 /* 2460 * Since we are going to append up to 1280 bytes (= IPV6_MMTU), 2461 * we almost always ask for an mbuf cluster for simplicity. 2462 * (MHLEN < IPV6_MMTU is almost always true) 2463 */ 2464#if IPV6_MMTU >= MCLBYTES 2465# error assumption failed about IPV6_MMTU and MCLBYTES 2466#endif 2467 MGETHDR(m, M_DONTWAIT, MT_HEADER); 2468 if (m && IPV6_MMTU >= MHLEN) 2469 MCLGET(m, M_DONTWAIT); 2470 if (!m) 2471 goto fail; 2472 m->m_pkthdr.rcvif = NULL; 2473 m->m_len = 0; 2474 maxlen = M_TRAILINGSPACE(m); 2475 maxlen = min(IPV6_MMTU, maxlen); 2476 /* just for safety */ 2477 if (maxlen < sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) + 2478 ((sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7)) { 2479 goto fail; 2480 } 2481 2482 { 2483 /* get ip6 linklocal address for ifp(my outgoing interface). */ 2484 struct in6_ifaddr *ia; 2485 if ((ia = in6ifa_ifpforlinklocal(ifp, 2486 IN6_IFF_NOTREADY| 2487 IN6_IFF_ANYCAST)) == NULL) 2488 goto fail; 2489 ifp_ll6 = &ia->ia_addr.sin6_addr; 2490 } 2491 2492 /* get ip6 linklocal address for the router. */ 2493 if (rt->rt_gateway && (rt->rt_flags & RTF_GATEWAY)) { 2494 struct sockaddr_in6 *sin6; 2495 sin6 = (struct sockaddr_in6 *)rt->rt_gateway; 2496 router_ll6 = &sin6->sin6_addr; 2497 if (!IN6_IS_ADDR_LINKLOCAL(router_ll6)) 2498 router_ll6 = (struct in6_addr *)NULL; 2499 } else 2500 router_ll6 = (struct in6_addr *)NULL; 2501 2502 /* ip6 */ 2503 ip6 = mtod(m, struct ip6_hdr *); 2504 ip6->ip6_flow = 0; 2505 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2506 ip6->ip6_vfc |= IPV6_VERSION; 2507 /* ip6->ip6_plen will be set later */ 2508 ip6->ip6_nxt = IPPROTO_ICMPV6; 2509 ip6->ip6_hlim = 255; 2510 /* ip6->ip6_src must be linklocal addr for my outgoing if. */ 2511 bcopy(ifp_ll6, &ip6->ip6_src, sizeof(struct in6_addr)); 2512 bcopy(&sip6->ip6_src, &ip6->ip6_dst, sizeof(struct in6_addr)); 2513 2514 /* ND Redirect */ 2515 nd_rd = (struct nd_redirect *)(ip6 + 1); 2516 nd_rd->nd_rd_type = ND_REDIRECT; 2517 nd_rd->nd_rd_code = 0; 2518 nd_rd->nd_rd_reserved = 0; 2519 if (rt->rt_flags & RTF_GATEWAY) { 2520 /* 2521 * nd_rd->nd_rd_target must be a link-local address in 2522 * better router cases. 2523 */ 2524 if (!router_ll6) 2525 goto fail; 2526 bcopy(router_ll6, &nd_rd->nd_rd_target, 2527 sizeof(nd_rd->nd_rd_target)); 2528 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2529 sizeof(nd_rd->nd_rd_dst)); 2530 } else { 2531 /* make sure redtgt == reddst */ 2532 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_target, 2533 sizeof(nd_rd->nd_rd_target)); 2534 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2535 sizeof(nd_rd->nd_rd_dst)); 2536 } 2537 2538 p = (u_char *)(nd_rd + 1); 2539 2540 if (!router_ll6) 2541 goto nolladdropt; 2542 2543 { 2544 /* target lladdr option */ 2545 struct rtentry *rt_router = NULL; 2546 int len; 2547 struct sockaddr_dl *sdl; 2548 struct nd_opt_hdr *nd_opt; 2549 char *lladdr; 2550 2551 rt_router = nd6_lookup(router_ll6, 0, ifp); 2552 if (!rt_router) 2553 goto nolladdropt; 2554 len = sizeof(*nd_opt) + ifp->if_addrlen; 2555 len = (len + 7) & ~7; /* round by 8 */ 2556 /* safety check */ 2557 if (len + (p - (u_char *)ip6) > maxlen) 2558 goto nolladdropt; 2559 if (!(rt_router->rt_flags & RTF_GATEWAY) && 2560 (rt_router->rt_flags & RTF_LLINFO) && 2561 (rt_router->rt_gateway->sa_family == AF_LINK) && 2562 (sdl = (struct sockaddr_dl *)rt_router->rt_gateway) && 2563 sdl->sdl_alen) { 2564 nd_opt = (struct nd_opt_hdr *)p; 2565 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 2566 nd_opt->nd_opt_len = len >> 3; 2567 lladdr = (char *)(nd_opt + 1); 2568 bcopy(LLADDR(sdl), lladdr, ifp->if_addrlen); 2569 p += len; 2570 } 2571 } 2572nolladdropt:; 2573 2574 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2575 2576 /* just to be safe */ 2577#ifdef M_DECRYPTED /*not openbsd*/ 2578 if (m0->m_flags & M_DECRYPTED) 2579 goto noredhdropt; 2580#endif 2581 if (p - (u_char *)ip6 > maxlen) 2582 goto noredhdropt; 2583 2584 { 2585 /* redirected header option */ 2586 int len; 2587 struct nd_opt_rd_hdr *nd_opt_rh; 2588 2589 /* 2590 * compute the maximum size for icmp6 redirect header option. 2591 * XXX room for auth header? 2592 */ 2593 len = maxlen - (p - (u_char *)ip6); 2594 len &= ~7; 2595 2596 /* This is just for simplicity. */ 2597 if (m0->m_pkthdr.len != m0->m_len) { 2598 if (m0->m_next) { 2599 m_freem(m0->m_next); 2600 m0->m_next = NULL; 2601 } 2602 m0->m_pkthdr.len = m0->m_len; 2603 } 2604 2605 /* 2606 * Redirected header option spec (RFC2461 4.6.3) talks nothing 2607 * about padding/truncate rule for the original IP packet. 2608 * From the discussion on IPv6imp in Feb 1999, 2609 * the consensus was: 2610 * - "attach as much as possible" is the goal 2611 * - pad if not aligned (original size can be guessed by 2612 * original ip6 header) 2613 * Following code adds the padding if it is simple enough, 2614 * and truncates if not. 2615 */ 2616 if (m0->m_next || m0->m_pkthdr.len != m0->m_len) 2617 panic("assumption failed in %s:%d", __FILE__, 2618 __LINE__); 2619 2620 if (len - sizeof(*nd_opt_rh) < m0->m_pkthdr.len) { 2621 /* not enough room, truncate */ 2622 m0->m_pkthdr.len = m0->m_len = len - 2623 sizeof(*nd_opt_rh); 2624 } else { 2625 /* enough room, pad or truncate */ 2626 size_t extra; 2627 2628 extra = m0->m_pkthdr.len % 8; 2629 if (extra) { 2630 /* pad if easy enough, truncate if not */ 2631 if (8 - extra <= M_TRAILINGSPACE(m0)) { 2632 /* pad */ 2633 m0->m_len += (8 - extra); 2634 m0->m_pkthdr.len += (8 - extra); 2635 } else { 2636 /* truncate */ 2637 m0->m_pkthdr.len -= extra; 2638 m0->m_len -= extra; 2639 } 2640 } 2641 len = m0->m_pkthdr.len + sizeof(*nd_opt_rh); 2642 m0->m_pkthdr.len = m0->m_len = len - 2643 sizeof(*nd_opt_rh); 2644 } 2645 2646 nd_opt_rh = (struct nd_opt_rd_hdr *)p; 2647 bzero(nd_opt_rh, sizeof(*nd_opt_rh)); 2648 nd_opt_rh->nd_opt_rh_type = ND_OPT_REDIRECTED_HEADER; 2649 nd_opt_rh->nd_opt_rh_len = len >> 3; 2650 p += sizeof(*nd_opt_rh); 2651 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2652 2653 /* connect m0 to m */ 2654 m_tag_delete_chain(m0, NULL); 2655 m0->m_flags &= ~M_PKTHDR; 2656 m->m_next = m0; 2657 m->m_pkthdr.len = m->m_len + m0->m_len; 2658 m0 = NULL; 2659 } 2660noredhdropt:; 2661 if (m0) { 2662 m_freem(m0); 2663 m0 = NULL; 2664 } 2665 2666 /* XXX: clear embedded link IDs in the inner header */ 2667 in6_clearscope(&sip6->ip6_src); 2668 in6_clearscope(&sip6->ip6_dst); 2669 in6_clearscope(&nd_rd->nd_rd_target); 2670 in6_clearscope(&nd_rd->nd_rd_dst); 2671 2672 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr)); 2673 2674 nd_rd->nd_rd_cksum = 0; 2675 nd_rd->nd_rd_cksum = in6_cksum(m, IPPROTO_ICMPV6, 2676 sizeof(*ip6), ntohs(ip6->ip6_plen)); 2677 2678 /* send the packet to outside... */ 2679 ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL); 2680 if (outif) { 2681 icmp6_ifstat_inc(outif, ifs6_out_msg); 2682 icmp6_ifstat_inc(outif, ifs6_out_redirect); 2683 } 2684 icmp6stat.icp6s_outhist[ND_REDIRECT]++; 2685 2686 return; 2687 2688fail: 2689 if (m) 2690 m_freem(m); 2691 if (m0) 2692 m_freem(m0); 2693} 2694 2695/* 2696 * ICMPv6 socket option processing. 2697 */ 2698int 2699icmp6_ctloutput(so, sopt) 2700 struct socket *so; 2701 struct sockopt *sopt; 2702{ 2703 int error = 0; 2704 int optlen; 2705 struct inpcb *inp = sotoinpcb(so); 2706 int level, op, optname; 2707 2708 if (sopt) { 2709 level = sopt->sopt_level; 2710 op = sopt->sopt_dir; 2711 optname = sopt->sopt_name; 2712 optlen = sopt->sopt_valsize; 2713 } else 2714 level = op = optname = optlen = 0; 2715 2716 if (level != IPPROTO_ICMPV6) { 2717 return EINVAL; 2718 } 2719 2720 switch (op) { 2721 case PRCO_SETOPT: 2722 switch (optname) { 2723 case ICMP6_FILTER: 2724 { 2725 struct icmp6_filter *p; 2726 2727 if (optlen != sizeof(*p)) { 2728 error = EMSGSIZE; 2729 break; 2730 } 2731 if (inp->in6p_icmp6filt == NULL) { 2732 error = EINVAL; 2733 break; 2734 } 2735 error = sooptcopyin(sopt, inp->in6p_icmp6filt, optlen, 2736 optlen); 2737 break; 2738 } 2739 2740 default: 2741 error = ENOPROTOOPT; 2742 break; 2743 } 2744 break; 2745 2746 case PRCO_GETOPT: 2747 switch (optname) { 2748 case ICMP6_FILTER: 2749 { 2750 if (inp->in6p_icmp6filt == NULL) { 2751 error = EINVAL; 2752 break; 2753 } 2754 error = sooptcopyout(sopt, inp->in6p_icmp6filt, 2755 sizeof(struct icmp6_filter)); 2756 break; 2757 } 2758 2759 default: 2760 error = ENOPROTOOPT; 2761 break; 2762 } 2763 break; 2764 } 2765 2766 return (error); 2767} 2768 2769/* 2770 * Perform rate limit check. 2771 * Returns 0 if it is okay to send the icmp6 packet. 2772 * Returns 1 if the router SHOULD NOT send this icmp6 packet due to rate 2773 * limitation. 2774 * 2775 * XXX per-destination/type check necessary? 2776 */ 2777static int 2778icmp6_ratelimit(dst, type, code) 2779 const struct in6_addr *dst; /* not used at this moment */ 2780 const int type; /* not used at this moment */ 2781 const int code; /* not used at this moment */ 2782{ 2783 int ret; 2784 2785 ret = 0; /* okay to send */ 2786 2787 /* PPS limit */ 2788 if (!ppsratecheck(&icmp6errppslim_last, &icmp6errpps_count, 2789 icmp6errppslim)) { 2790 /* The packet is subject to rate limit */ 2791 ret++; 2792 } 2793 2794 return ret; 2795} 2796