icmp6.c revision 1.113.4.1
1 /* $NetBSD: icmp6.c,v 1.113.4.1 2006/02/04 14:18:52 simonb Exp $ */ 2 /* $KAME: icmp6.c,v 1.217 2001/06/20 15:03:29 jinmei 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 * 3. 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 <sys/cdefs.h> 65 __KERNEL_RCSID(0, "$NetBSD: icmp6.c,v 1.113.4.1 2006/02/04 14:18:52 simonb Exp $"); 66 67 #include "opt_inet.h" 68 #include "opt_ipsec.h" 69 70 #include <sys/param.h> 71 #include <sys/systm.h> 72 #include <sys/malloc.h> 73 #include <sys/mbuf.h> 74 #include <sys/protosw.h> 75 #include <sys/socket.h> 76 #include <sys/socketvar.h> 77 #include <sys/time.h> 78 #include <sys/kernel.h> 79 #include <sys/syslog.h> 80 #include <sys/domain.h> 81 #include <sys/sysctl.h> 82 83 #include <net/if.h> 84 #include <net/route.h> 85 #include <net/if_dl.h> 86 #include <net/if_types.h> 87 88 #include <netinet/in.h> 89 #include <netinet/in_var.h> 90 #include <netinet/ip6.h> 91 #include <netinet6/ip6_var.h> 92 #include <netinet/icmp6.h> 93 #include <netinet6/mld6_var.h> 94 #include <netinet6/in6_pcb.h> 95 #include <netinet6/nd6.h> 96 #include <netinet6/in6_ifattach.h> 97 #include <netinet6/ip6protosw.h> 98 #include <netinet6/scope6_var.h> 99 100 #ifdef IPSEC 101 #include <netinet6/ipsec.h> 102 #include <netkey/key.h> 103 #endif 104 105 #include "faith.h" 106 #if defined(NFAITH) && 0 < NFAITH 107 #include <net/if_faith.h> 108 #endif 109 110 #include <net/net_osdep.h> 111 112 extern struct domain inet6domain; 113 114 struct icmp6stat icmp6stat; 115 116 extern struct inpcbtable raw6cbtable; 117 extern int icmp6errppslim; 118 static int icmp6errpps_count = 0; 119 static struct timeval icmp6errppslim_last; 120 extern int icmp6_nodeinfo; 121 122 /* 123 * List of callbacks to notify when Path MTU changes are made. 124 */ 125 struct icmp6_mtudisc_callback { 126 LIST_ENTRY(icmp6_mtudisc_callback) mc_list; 127 void (*mc_func) __P((struct in6_addr *)); 128 }; 129 130 LIST_HEAD(, icmp6_mtudisc_callback) icmp6_mtudisc_callbacks = 131 LIST_HEAD_INITIALIZER(&icmp6_mtudisc_callbacks); 132 133 static struct rttimer_queue *icmp6_mtudisc_timeout_q = NULL; 134 extern int pmtu_expire; 135 136 /* XXX do these values make any sense? */ 137 static int icmp6_mtudisc_hiwat = 1280; 138 static int icmp6_mtudisc_lowat = 256; 139 140 /* 141 * keep track of # of redirect routes. 142 */ 143 static struct rttimer_queue *icmp6_redirect_timeout_q = NULL; 144 145 /* XXX experimental, turned off */ 146 static int icmp6_redirect_hiwat = -1; 147 static int icmp6_redirect_lowat = -1; 148 149 static void icmp6_errcount __P((struct icmp6errstat *, int, int)); 150 static int icmp6_rip6_input __P((struct mbuf **, int)); 151 static int icmp6_ratelimit __P((const struct in6_addr *, const int, const int)); 152 static const char *icmp6_redirect_diag __P((struct in6_addr *, 153 struct in6_addr *, struct in6_addr *)); 154 static struct mbuf *ni6_input __P((struct mbuf *, int)); 155 static struct mbuf *ni6_nametodns __P((const char *, int, int)); 156 static int ni6_dnsmatch __P((const char *, int, const char *, int)); 157 static int ni6_addrs __P((struct icmp6_nodeinfo *, struct mbuf *, 158 struct ifnet **, char *)); 159 static int ni6_store_addrs __P((struct icmp6_nodeinfo *, struct icmp6_nodeinfo *, 160 struct ifnet *, int)); 161 static int icmp6_notify_error __P((struct mbuf *, int, int, int)); 162 static struct rtentry *icmp6_mtudisc_clone __P((struct sockaddr *)); 163 static void icmp6_mtudisc_timeout __P((struct rtentry *, struct rttimer *)); 164 static void icmp6_redirect_timeout __P((struct rtentry *, struct rttimer *)); 165 166 void 167 icmp6_init() 168 { 169 mld6_init(); 170 icmp6_mtudisc_timeout_q = rt_timer_queue_create(pmtu_expire); 171 icmp6_redirect_timeout_q = rt_timer_queue_create(icmp6_redirtimeout); 172 } 173 174 static void 175 icmp6_errcount(stat, type, code) 176 struct icmp6errstat *stat; 177 int type, code; 178 { 179 switch (type) { 180 case ICMP6_DST_UNREACH: 181 switch (code) { 182 case ICMP6_DST_UNREACH_NOROUTE: 183 stat->icp6errs_dst_unreach_noroute++; 184 return; 185 case ICMP6_DST_UNREACH_ADMIN: 186 stat->icp6errs_dst_unreach_admin++; 187 return; 188 case ICMP6_DST_UNREACH_BEYONDSCOPE: 189 stat->icp6errs_dst_unreach_beyondscope++; 190 return; 191 case ICMP6_DST_UNREACH_ADDR: 192 stat->icp6errs_dst_unreach_addr++; 193 return; 194 case ICMP6_DST_UNREACH_NOPORT: 195 stat->icp6errs_dst_unreach_noport++; 196 return; 197 } 198 break; 199 case ICMP6_PACKET_TOO_BIG: 200 stat->icp6errs_packet_too_big++; 201 return; 202 case ICMP6_TIME_EXCEEDED: 203 switch (code) { 204 case ICMP6_TIME_EXCEED_TRANSIT: 205 stat->icp6errs_time_exceed_transit++; 206 return; 207 case ICMP6_TIME_EXCEED_REASSEMBLY: 208 stat->icp6errs_time_exceed_reassembly++; 209 return; 210 } 211 break; 212 case ICMP6_PARAM_PROB: 213 switch (code) { 214 case ICMP6_PARAMPROB_HEADER: 215 stat->icp6errs_paramprob_header++; 216 return; 217 case ICMP6_PARAMPROB_NEXTHEADER: 218 stat->icp6errs_paramprob_nextheader++; 219 return; 220 case ICMP6_PARAMPROB_OPTION: 221 stat->icp6errs_paramprob_option++; 222 return; 223 } 224 break; 225 case ND_REDIRECT: 226 stat->icp6errs_redirect++; 227 return; 228 } 229 stat->icp6errs_unknown++; 230 } 231 232 /* 233 * Register a Path MTU Discovery callback. 234 */ 235 void 236 icmp6_mtudisc_callback_register(func) 237 void (*func) __P((struct in6_addr *)); 238 { 239 struct icmp6_mtudisc_callback *mc; 240 241 for (mc = LIST_FIRST(&icmp6_mtudisc_callbacks); mc != NULL; 242 mc = LIST_NEXT(mc, mc_list)) { 243 if (mc->mc_func == func) 244 return; 245 } 246 247 mc = malloc(sizeof(*mc), M_PCB, M_NOWAIT); 248 if (mc == NULL) 249 panic("icmp6_mtudisc_callback_register"); 250 251 mc->mc_func = func; 252 LIST_INSERT_HEAD(&icmp6_mtudisc_callbacks, mc, mc_list); 253 } 254 255 /* 256 * A wrapper function for icmp6_error() necessary when the erroneous packet 257 * may not contain enough scope zone information. 258 */ 259 void 260 icmp6_error2(m, type, code, param, ifp) 261 struct mbuf *m; 262 int type, code, param; 263 struct ifnet *ifp; 264 { 265 struct ip6_hdr *ip6; 266 267 if (ifp == NULL) 268 return; 269 270 if (m->m_len < sizeof(struct ip6_hdr)) { 271 m = m_pullup(m, sizeof(struct ip6_hdr)); 272 if (m == NULL) 273 return; 274 } 275 276 ip6 = mtod(m, struct ip6_hdr *); 277 278 if (in6_setscope(&ip6->ip6_src, ifp, NULL) != 0) 279 return; 280 if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0) 281 return; 282 283 icmp6_error(m, type, code, param); 284 } 285 286 /* 287 * Generate an error packet of type error in response to bad IP6 packet. 288 */ 289 void 290 icmp6_error(m, type, code, param) 291 struct mbuf *m; 292 int type, code, param; 293 { 294 struct ip6_hdr *oip6, *nip6; 295 struct icmp6_hdr *icmp6; 296 u_int preplen; 297 int off; 298 int nxt; 299 300 icmp6stat.icp6s_error++; 301 302 /* count per-type-code statistics */ 303 icmp6_errcount(&icmp6stat.icp6s_outerrhist, type, code); 304 305 if (m->m_flags & M_DECRYPTED) { 306 icmp6stat.icp6s_canterror++; 307 goto freeit; 308 } 309 310 if (m->m_len < sizeof(struct ip6_hdr)) { 311 m = m_pullup(m, sizeof(struct ip6_hdr)); 312 if (m == NULL) 313 return; 314 } 315 oip6 = mtod(m, struct ip6_hdr *); 316 317 /* 318 * If the destination address of the erroneous packet is a multicast 319 * address, or the packet was sent using link-layer multicast, 320 * we should basically suppress sending an error (RFC 2463, Section 321 * 2.4). 322 * We have two exceptions (the item e.2 in that section): 323 * - the Pakcet Too Big message can be sent for path MTU discovery. 324 * - the Parameter Problem Message that can be allowed an icmp6 error 325 * in the option type field. This check has been done in 326 * ip6_unknown_opt(), so we can just check the type and code. 327 */ 328 if ((m->m_flags & (M_BCAST|M_MCAST) || 329 IN6_IS_ADDR_MULTICAST(&oip6->ip6_dst)) && 330 (type != ICMP6_PACKET_TOO_BIG && 331 (type != ICMP6_PARAM_PROB || 332 code != ICMP6_PARAMPROB_OPTION))) 333 goto freeit; 334 335 /* 336 * RFC 2463, 2.4 (e.5): source address check. 337 * XXX: the case of anycast source? 338 */ 339 if (IN6_IS_ADDR_UNSPECIFIED(&oip6->ip6_src) || 340 IN6_IS_ADDR_MULTICAST(&oip6->ip6_src)) 341 goto freeit; 342 343 /* 344 * If we are about to send ICMPv6 against ICMPv6 error/redirect, 345 * don't do it. 346 */ 347 nxt = -1; 348 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); 349 if (off >= 0 && nxt == IPPROTO_ICMPV6) { 350 struct icmp6_hdr *icp; 351 352 IP6_EXTHDR_GET(icp, struct icmp6_hdr *, m, off, 353 sizeof(*icp)); 354 if (icp == NULL) { 355 icmp6stat.icp6s_tooshort++; 356 return; 357 } 358 if (icp->icmp6_type < ICMP6_ECHO_REQUEST || 359 icp->icmp6_type == ND_REDIRECT) { 360 /* 361 * ICMPv6 error 362 * Special case: for redirect (which is 363 * informational) we must not send icmp6 error. 364 */ 365 icmp6stat.icp6s_canterror++; 366 goto freeit; 367 } else { 368 /* ICMPv6 informational - send the error */ 369 } 370 } 371 #if 0 /* controversial */ 372 else if (off >= 0 && nxt == IPPROTO_ESP) { 373 /* 374 * It could be ICMPv6 error inside ESP. Take a safer side, 375 * don't respond. 376 */ 377 icmp6stat.icp6s_canterror++; 378 goto freeit; 379 } 380 #endif 381 else { 382 /* non-ICMPv6 - send the error */ 383 } 384 385 oip6 = mtod(m, struct ip6_hdr *); /* adjust pointer */ 386 387 /* Finally, do rate limitation check. */ 388 if (icmp6_ratelimit(&oip6->ip6_src, type, code)) { 389 icmp6stat.icp6s_toofreq++; 390 goto freeit; 391 } 392 393 /* 394 * OK, ICMP6 can be generated. 395 */ 396 397 if (m->m_pkthdr.len >= ICMPV6_PLD_MAXLEN) 398 m_adj(m, ICMPV6_PLD_MAXLEN - m->m_pkthdr.len); 399 400 preplen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 401 M_PREPEND(m, preplen, M_DONTWAIT); 402 if (m && m->m_len < preplen) 403 m = m_pullup(m, preplen); 404 if (m == NULL) { 405 nd6log((LOG_DEBUG, "ENOBUFS in icmp6_error %d\n", __LINE__)); 406 return; 407 } 408 409 nip6 = mtod(m, struct ip6_hdr *); 410 nip6->ip6_src = oip6->ip6_src; 411 nip6->ip6_dst = oip6->ip6_dst; 412 413 in6_clearscope(&oip6->ip6_src); 414 in6_clearscope(&oip6->ip6_dst); 415 416 icmp6 = (struct icmp6_hdr *)(nip6 + 1); 417 icmp6->icmp6_type = type; 418 icmp6->icmp6_code = code; 419 icmp6->icmp6_pptr = htonl((u_int32_t)param); 420 421 /* 422 * icmp6_reflect() is designed to be in the input path. 423 * icmp6_error() can be called from both input and outut path, 424 * and if we are in output path rcvif could contain bogus value. 425 * clear m->m_pkthdr.rcvif for safety, we should have enough scope 426 * information in ip header (nip6). 427 */ 428 m->m_pkthdr.rcvif = NULL; 429 430 icmp6stat.icp6s_outhist[type]++; 431 icmp6_reflect(m, sizeof(struct ip6_hdr)); /* header order: IPv6 - ICMPv6 */ 432 433 return; 434 435 freeit: 436 /* 437 * If we can't tell wheter or not we can generate ICMP6, free it. 438 */ 439 m_freem(m); 440 } 441 442 /* 443 * Process a received ICMP6 message. 444 */ 445 int 446 icmp6_input(mp, offp, proto) 447 struct mbuf **mp; 448 int *offp, proto; 449 { 450 struct mbuf *m = *mp, *n; 451 struct ip6_hdr *ip6, *nip6; 452 struct icmp6_hdr *icmp6, *nicmp6; 453 int off = *offp; 454 int icmp6len = m->m_pkthdr.len - *offp; 455 int code, sum, noff; 456 457 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_msg); 458 459 /* 460 * Locate icmp6 structure in mbuf, and check 461 * that not corrupted and of at least minimum length 462 */ 463 464 ip6 = mtod(m, struct ip6_hdr *); 465 if (icmp6len < sizeof(struct icmp6_hdr)) { 466 icmp6stat.icp6s_tooshort++; 467 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_error); 468 goto freeit; 469 } 470 471 /* 472 * calculate the checksum 473 */ 474 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 475 if (icmp6 == NULL) { 476 icmp6stat.icp6s_tooshort++; 477 /* m is invalid */ 478 /*icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_error);*/ 479 return IPPROTO_DONE; 480 } 481 KASSERT(IP6_HDR_ALIGNED_P(icmp6)); 482 code = icmp6->icmp6_code; 483 484 if ((sum = in6_cksum(m, IPPROTO_ICMPV6, off, icmp6len)) != 0) { 485 nd6log((LOG_ERR, 486 "ICMP6 checksum error(%d|%x) %s\n", 487 icmp6->icmp6_type, sum, ip6_sprintf(&ip6->ip6_src))); 488 icmp6stat.icp6s_checksum++; 489 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_error); 490 goto freeit; 491 } 492 493 #if defined(NFAITH) && 0 < NFAITH 494 if (faithprefix(&ip6->ip6_dst)) { 495 /* 496 * Deliver very specific ICMP6 type only. 497 * This is important to deilver TOOBIG. Otherwise PMTUD 498 * will not work. 499 */ 500 switch (icmp6->icmp6_type) { 501 case ICMP6_DST_UNREACH: 502 case ICMP6_PACKET_TOO_BIG: 503 case ICMP6_TIME_EXCEEDED: 504 break; 505 default: 506 goto freeit; 507 } 508 } 509 #endif 510 511 icmp6stat.icp6s_inhist[icmp6->icmp6_type]++; 512 513 switch (icmp6->icmp6_type) { 514 case ICMP6_DST_UNREACH: 515 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_dstunreach); 516 switch (code) { 517 case ICMP6_DST_UNREACH_NOROUTE: 518 code = PRC_UNREACH_NET; 519 break; 520 case ICMP6_DST_UNREACH_ADMIN: 521 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_adminprohib); 522 code = PRC_UNREACH_PROTOCOL; /* is this a good code? */ 523 break; 524 case ICMP6_DST_UNREACH_ADDR: 525 code = PRC_HOSTDEAD; 526 break; 527 #ifdef COMPAT_RFC1885 528 case ICMP6_DST_UNREACH_NOTNEIGHBOR: 529 code = PRC_UNREACH_SRCFAIL; 530 break; 531 #else 532 case ICMP6_DST_UNREACH_BEYONDSCOPE: 533 /* I mean "source address was incorrect." */ 534 code = PRC_UNREACH_NET; 535 break; 536 #endif 537 case ICMP6_DST_UNREACH_NOPORT: 538 code = PRC_UNREACH_PORT; 539 break; 540 default: 541 goto badcode; 542 } 543 goto deliver; 544 545 case ICMP6_PACKET_TOO_BIG: 546 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_pkttoobig); 547 548 code = PRC_MSGSIZE; 549 550 /* 551 * Updating the path MTU will be done after examining 552 * intermediate extension headers. 553 */ 554 goto deliver; 555 556 case ICMP6_TIME_EXCEEDED: 557 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_timeexceed); 558 switch (code) { 559 case ICMP6_TIME_EXCEED_TRANSIT: 560 code = PRC_TIMXCEED_INTRANS; 561 break; 562 case ICMP6_TIME_EXCEED_REASSEMBLY: 563 code = PRC_TIMXCEED_REASS; 564 break; 565 default: 566 goto badcode; 567 } 568 goto deliver; 569 570 case ICMP6_PARAM_PROB: 571 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_paramprob); 572 switch (code) { 573 case ICMP6_PARAMPROB_NEXTHEADER: 574 code = PRC_UNREACH_PROTOCOL; 575 break; 576 case ICMP6_PARAMPROB_HEADER: 577 case ICMP6_PARAMPROB_OPTION: 578 code = PRC_PARAMPROB; 579 break; 580 default: 581 goto badcode; 582 } 583 goto deliver; 584 585 case ICMP6_ECHO_REQUEST: 586 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echo); 587 if (code != 0) 588 goto badcode; 589 /* 590 * Copy mbuf to send to two data paths: userland socket(s), 591 * and to the querier (echo reply). 592 * m: a copy for socket, n: a copy for querier 593 */ 594 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 595 /* Give up local */ 596 n = m; 597 m = NULL; 598 goto deliverecho; 599 } 600 /* 601 * If the first mbuf is shared, or the first mbuf is too short, 602 * copy the first part of the data into a fresh mbuf. 603 * Otherwise, we will wrongly overwrite both copies. 604 */ 605 if ((n->m_flags & M_EXT) != 0 || 606 n->m_len < off + sizeof(struct icmp6_hdr)) { 607 struct mbuf *n0 = n; 608 const int maxlen = sizeof(*nip6) + sizeof(*nicmp6); 609 610 /* 611 * Prepare an internal mbuf. m_pullup() doesn't 612 * always copy the length we specified. 613 */ 614 if (maxlen >= MCLBYTES) { 615 /* Give up remote */ 616 m_freem(n0); 617 break; 618 } 619 MGETHDR(n, M_DONTWAIT, n0->m_type); 620 if (n && maxlen >= MHLEN) { 621 MCLGET(n, M_DONTWAIT); 622 if ((n->m_flags & M_EXT) == 0) { 623 m_free(n); 624 n = NULL; 625 } 626 } 627 if (n == NULL) { 628 /* Give up local */ 629 m_freem(n0); 630 n = m; 631 m = NULL; 632 goto deliverecho; 633 } 634 M_MOVE_PKTHDR(n, n0); 635 /* 636 * Copy IPv6 and ICMPv6 only. 637 */ 638 nip6 = mtod(n, struct ip6_hdr *); 639 bcopy(ip6, nip6, sizeof(struct ip6_hdr)); 640 nicmp6 = (struct icmp6_hdr *)(nip6 + 1); 641 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr)); 642 noff = sizeof(struct ip6_hdr); 643 n->m_len = noff + sizeof(struct icmp6_hdr); 644 /* 645 * Adjust mbuf. ip6_plen will be adjusted in 646 * ip6_output(). 647 * n->m_pkthdr.len == n0->m_pkthdr.len at this point. 648 */ 649 n->m_pkthdr.len += noff + sizeof(struct icmp6_hdr); 650 n->m_pkthdr.len -= (off + sizeof(struct icmp6_hdr)); 651 m_adj(n0, off + sizeof(struct icmp6_hdr)); 652 n->m_next = n0; 653 } else { 654 deliverecho: 655 nip6 = mtod(n, struct ip6_hdr *); 656 nicmp6 = (struct icmp6_hdr *)((caddr_t)nip6 + off); 657 noff = off; 658 } 659 nicmp6->icmp6_type = ICMP6_ECHO_REPLY; 660 nicmp6->icmp6_code = 0; 661 if (n) { 662 icmp6stat.icp6s_reflect++; 663 icmp6stat.icp6s_outhist[ICMP6_ECHO_REPLY]++; 664 icmp6_reflect(n, noff); 665 } 666 if (!m) 667 goto freeit; 668 break; 669 670 case ICMP6_ECHO_REPLY: 671 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echoreply); 672 if (code != 0) 673 goto badcode; 674 break; 675 676 case MLD_LISTENER_QUERY: 677 case MLD_LISTENER_REPORT: 678 if (icmp6len < sizeof(struct mld_hdr)) 679 goto badlen; 680 if (icmp6->icmp6_type == MLD_LISTENER_QUERY) /* XXX: ugly... */ 681 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldquery); 682 else 683 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldreport); 684 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 685 /* give up local */ 686 mld6_input(m, off); 687 m = NULL; 688 goto freeit; 689 } 690 mld6_input(n, off); 691 /* m stays. */ 692 break; 693 694 case MLD_LISTENER_DONE: 695 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mlddone); 696 if (icmp6len < sizeof(struct mld_hdr)) /* necessary? */ 697 goto badlen; 698 break; /* nothing to be done in kernel */ 699 700 case MLD_MTRACE_RESP: 701 case MLD_MTRACE: 702 /* XXX: these two are experimental. not officially defined. */ 703 /* XXX: per-interface statistics? */ 704 break; /* just pass it to applications */ 705 706 case ICMP6_WRUREQUEST: /* ICMP6_FQDN_QUERY */ 707 { 708 enum { WRU, FQDN } mode; 709 710 if (!icmp6_nodeinfo) 711 break; 712 713 if (icmp6len == sizeof(struct icmp6_hdr) + 4) 714 mode = WRU; 715 else if (icmp6len >= sizeof(struct icmp6_nodeinfo)) 716 mode = FQDN; 717 else 718 goto badlen; 719 720 if (mode == FQDN) { 721 n = m_copym(m, 0, M_COPYALL, M_DONTWAIT); 722 if (n) 723 n = ni6_input(n, off); 724 /* XXX meaningless if n == NULL */ 725 noff = sizeof(struct ip6_hdr); 726 } else { 727 u_char *p; 728 int maxlen, maxhlen; 729 730 if ((icmp6_nodeinfo & 5) != 5) 731 break; 732 733 if (code != 0) 734 goto badcode; 735 maxlen = sizeof(*nip6) + sizeof(*nicmp6) + 4; 736 if (maxlen >= MCLBYTES) { 737 /* Give up remote */ 738 break; 739 } 740 MGETHDR(n, M_DONTWAIT, m->m_type); 741 if (n && maxlen > MHLEN) { 742 MCLGET(n, M_DONTWAIT); 743 if ((n->m_flags & M_EXT) == 0) { 744 m_free(n); 745 n = NULL; 746 } 747 } 748 if (n == NULL) { 749 /* Give up remote */ 750 break; 751 } 752 n->m_pkthdr.rcvif = NULL; 753 n->m_len = 0; 754 maxhlen = M_TRAILINGSPACE(n) - maxlen; 755 if (maxhlen > hostnamelen) 756 maxhlen = hostnamelen; 757 /* 758 * Copy IPv6 and ICMPv6 only. 759 */ 760 nip6 = mtod(n, struct ip6_hdr *); 761 bcopy(ip6, nip6, sizeof(struct ip6_hdr)); 762 nicmp6 = (struct icmp6_hdr *)(nip6 + 1); 763 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr)); 764 p = (u_char *)(nicmp6 + 1); 765 bzero(p, 4); 766 bcopy(hostname, p + 4, maxhlen); /* meaningless TTL */ 767 noff = sizeof(struct ip6_hdr); 768 M_COPY_PKTHDR(n, m); /* just for rcvif */ 769 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) + 770 sizeof(struct icmp6_hdr) + 4 + maxhlen; 771 nicmp6->icmp6_type = ICMP6_WRUREPLY; 772 nicmp6->icmp6_code = 0; 773 } 774 #undef hostnamelen 775 if (n) { 776 icmp6stat.icp6s_reflect++; 777 icmp6stat.icp6s_outhist[ICMP6_WRUREPLY]++; 778 icmp6_reflect(n, noff); 779 } 780 break; 781 } 782 783 case ICMP6_WRUREPLY: 784 if (code != 0) 785 goto badcode; 786 break; 787 788 case ND_ROUTER_SOLICIT: 789 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routersolicit); 790 if (code != 0) 791 goto badcode; 792 if (icmp6len < sizeof(struct nd_router_solicit)) 793 goto badlen; 794 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 795 /* give up local */ 796 nd6_rs_input(m, off, icmp6len); 797 m = NULL; 798 goto freeit; 799 } 800 nd6_rs_input(n, off, icmp6len); 801 /* m stays. */ 802 break; 803 804 case ND_ROUTER_ADVERT: 805 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routeradvert); 806 if (code != 0) 807 goto badcode; 808 if (icmp6len < sizeof(struct nd_router_advert)) 809 goto badlen; 810 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 811 /* give up local */ 812 nd6_ra_input(m, off, icmp6len); 813 m = NULL; 814 goto freeit; 815 } 816 nd6_ra_input(n, off, icmp6len); 817 /* m stays. */ 818 break; 819 820 case ND_NEIGHBOR_SOLICIT: 821 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighborsolicit); 822 if (code != 0) 823 goto badcode; 824 if (icmp6len < sizeof(struct nd_neighbor_solicit)) 825 goto badlen; 826 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 827 /* give up local */ 828 nd6_ns_input(m, off, icmp6len); 829 m = NULL; 830 goto freeit; 831 } 832 nd6_ns_input(n, off, icmp6len); 833 /* m stays. */ 834 break; 835 836 case ND_NEIGHBOR_ADVERT: 837 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighboradvert); 838 if (code != 0) 839 goto badcode; 840 if (icmp6len < sizeof(struct nd_neighbor_advert)) 841 goto badlen; 842 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 843 /* give up local */ 844 nd6_na_input(m, off, icmp6len); 845 m = NULL; 846 goto freeit; 847 } 848 nd6_na_input(n, off, icmp6len); 849 /* m stays. */ 850 break; 851 852 case ND_REDIRECT: 853 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_redirect); 854 if (code != 0) 855 goto badcode; 856 if (icmp6len < sizeof(struct nd_redirect)) 857 goto badlen; 858 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 859 /* give up local */ 860 icmp6_redirect_input(m, off); 861 m = NULL; 862 goto freeit; 863 } 864 icmp6_redirect_input(n, off); 865 /* m stays. */ 866 break; 867 868 case ICMP6_ROUTER_RENUMBERING: 869 if (code != ICMP6_ROUTER_RENUMBERING_COMMAND && 870 code != ICMP6_ROUTER_RENUMBERING_RESULT) 871 goto badcode; 872 if (icmp6len < sizeof(struct icmp6_router_renum)) 873 goto badlen; 874 break; 875 876 default: 877 nd6log((LOG_DEBUG, 878 "icmp6_input: unknown type %d(src=%s, dst=%s, ifid=%d)\n", 879 icmp6->icmp6_type, ip6_sprintf(&ip6->ip6_src), 880 ip6_sprintf(&ip6->ip6_dst), 881 m->m_pkthdr.rcvif ? m->m_pkthdr.rcvif->if_index : 0)); 882 if (icmp6->icmp6_type < ICMP6_ECHO_REQUEST) { 883 /* ICMPv6 error: MUST deliver it by spec... */ 884 code = PRC_NCMDS; 885 /* deliver */ 886 } else { 887 /* ICMPv6 informational: MUST not deliver */ 888 break; 889 } 890 deliver: 891 if (icmp6_notify_error(m, off, icmp6len, code)) { 892 /* In this case, m should've been freed. */ 893 return (IPPROTO_DONE); 894 } 895 break; 896 897 badcode: 898 icmp6stat.icp6s_badcode++; 899 break; 900 901 badlen: 902 icmp6stat.icp6s_badlen++; 903 break; 904 } 905 906 /* deliver the packet to appropriate sockets */ 907 icmp6_rip6_input(&m, *offp); 908 909 return IPPROTO_DONE; 910 911 freeit: 912 m_freem(m); 913 return IPPROTO_DONE; 914 } 915 916 static int 917 icmp6_notify_error(m, off, icmp6len, code) 918 struct mbuf *m; 919 int off, icmp6len; 920 { 921 struct icmp6_hdr *icmp6; 922 struct ip6_hdr *eip6; 923 u_int32_t notifymtu; 924 struct sockaddr_in6 icmp6src, icmp6dst; 925 926 if (icmp6len < sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr)) { 927 icmp6stat.icp6s_tooshort++; 928 goto freeit; 929 } 930 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, 931 sizeof(*icmp6) + sizeof(struct ip6_hdr)); 932 if (icmp6 == NULL) { 933 icmp6stat.icp6s_tooshort++; 934 return (-1); 935 } 936 eip6 = (struct ip6_hdr *)(icmp6 + 1); 937 938 /* Detect the upper level protocol */ 939 { 940 void (*ctlfunc) __P((int, struct sockaddr *, void *)); 941 u_int8_t nxt = eip6->ip6_nxt; 942 int eoff = off + sizeof(struct icmp6_hdr) + 943 sizeof(struct ip6_hdr); 944 struct ip6ctlparam ip6cp; 945 struct in6_addr *finaldst = NULL; 946 int icmp6type = icmp6->icmp6_type; 947 struct ip6_frag *fh; 948 struct ip6_rthdr *rth; 949 struct ip6_rthdr0 *rth0; 950 int rthlen; 951 952 while (1) { /* XXX: should avoid infinite loop explicitly? */ 953 struct ip6_ext *eh; 954 955 switch (nxt) { 956 case IPPROTO_HOPOPTS: 957 case IPPROTO_DSTOPTS: 958 case IPPROTO_AH: 959 IP6_EXTHDR_GET(eh, struct ip6_ext *, m, 960 eoff, sizeof(*eh)); 961 if (eh == NULL) { 962 icmp6stat.icp6s_tooshort++; 963 return (-1); 964 } 965 966 if (nxt == IPPROTO_AH) 967 eoff += (eh->ip6e_len + 2) << 2; 968 else 969 eoff += (eh->ip6e_len + 1) << 3; 970 nxt = eh->ip6e_nxt; 971 break; 972 case IPPROTO_ROUTING: 973 /* 974 * When the erroneous packet contains a 975 * routing header, we should examine the 976 * header to determine the final destination. 977 * Otherwise, we can't properly update 978 * information that depends on the final 979 * destination (e.g. path MTU). 980 */ 981 IP6_EXTHDR_GET(rth, struct ip6_rthdr *, m, 982 eoff, sizeof(*rth)); 983 if (rth == NULL) { 984 icmp6stat.icp6s_tooshort++; 985 return (-1); 986 } 987 rthlen = (rth->ip6r_len + 1) << 3; 988 /* 989 * XXX: currently there is no 990 * officially defined type other 991 * than type-0. 992 * Note that if the segment left field 993 * is 0, all intermediate hops must 994 * have been passed. 995 */ 996 if (rth->ip6r_segleft && 997 rth->ip6r_type == IPV6_RTHDR_TYPE_0) { 998 int hops; 999 1000 IP6_EXTHDR_GET(rth0, 1001 struct ip6_rthdr0 *, m, 1002 eoff, rthlen); 1003 if (rth0 == NULL) { 1004 icmp6stat.icp6s_tooshort++; 1005 return (-1); 1006 } 1007 /* just ignore a bogus header */ 1008 if ((rth0->ip6r0_len % 2) == 0 && 1009 (hops = rth0->ip6r0_len/2)) 1010 finaldst = (struct in6_addr *)(rth0 + 1) + (hops - 1); 1011 } 1012 eoff += rthlen; 1013 nxt = rth->ip6r_nxt; 1014 break; 1015 case IPPROTO_FRAGMENT: 1016 IP6_EXTHDR_GET(fh, struct ip6_frag *, m, 1017 eoff, sizeof(*fh)); 1018 if (fh == NULL) { 1019 icmp6stat.icp6s_tooshort++; 1020 return (-1); 1021 } 1022 /* 1023 * Data after a fragment header is meaningless 1024 * unless it is the first fragment, but 1025 * we'll go to the notify label for path MTU 1026 * discovery. 1027 */ 1028 if (fh->ip6f_offlg & IP6F_OFF_MASK) 1029 goto notify; 1030 1031 eoff += sizeof(struct ip6_frag); 1032 nxt = fh->ip6f_nxt; 1033 break; 1034 default: 1035 /* 1036 * This case includes ESP and the No Next 1037 * Header. In such cases going to the notify 1038 * label does not have any meaning 1039 * (i.e. ctlfunc will be NULL), but we go 1040 * anyway since we might have to update 1041 * path MTU information. 1042 */ 1043 goto notify; 1044 } 1045 } 1046 notify: 1047 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, 1048 sizeof(*icmp6) + sizeof(struct ip6_hdr)); 1049 if (icmp6 == NULL) { 1050 icmp6stat.icp6s_tooshort++; 1051 return (-1); 1052 } 1053 1054 /* 1055 * retrieve parameters from the inner IPv6 header, and convert 1056 * them into sockaddr structures. 1057 * XXX: there is no guarantee that the source or destination 1058 * addresses of the inner packet are in the same scope zone as 1059 * the addresses of the icmp packet. But there is no other 1060 * way to determine the zone. 1061 */ 1062 eip6 = (struct ip6_hdr *)(icmp6 + 1); 1063 1064 bzero(&icmp6dst, sizeof(icmp6dst)); 1065 icmp6dst.sin6_len = sizeof(struct sockaddr_in6); 1066 icmp6dst.sin6_family = AF_INET6; 1067 if (finaldst == NULL) 1068 icmp6dst.sin6_addr = eip6->ip6_dst; 1069 else 1070 icmp6dst.sin6_addr = *finaldst; 1071 if (in6_setscope(&icmp6dst.sin6_addr, m->m_pkthdr.rcvif, NULL)) 1072 goto freeit; 1073 bzero(&icmp6src, sizeof(icmp6src)); 1074 icmp6src.sin6_len = sizeof(struct sockaddr_in6); 1075 icmp6src.sin6_family = AF_INET6; 1076 icmp6src.sin6_addr = eip6->ip6_src; 1077 if (in6_setscope(&icmp6src.sin6_addr, m->m_pkthdr.rcvif, NULL)) 1078 goto freeit; 1079 icmp6src.sin6_flowinfo = 1080 (eip6->ip6_flow & IPV6_FLOWLABEL_MASK); 1081 1082 if (finaldst == NULL) 1083 finaldst = &eip6->ip6_dst; 1084 ip6cp.ip6c_m = m; 1085 ip6cp.ip6c_icmp6 = icmp6; 1086 ip6cp.ip6c_ip6 = (struct ip6_hdr *)(icmp6 + 1); 1087 ip6cp.ip6c_off = eoff; 1088 ip6cp.ip6c_finaldst = finaldst; 1089 ip6cp.ip6c_src = &icmp6src; 1090 ip6cp.ip6c_nxt = nxt; 1091 1092 if (icmp6type == ICMP6_PACKET_TOO_BIG) { 1093 notifymtu = ntohl(icmp6->icmp6_mtu); 1094 ip6cp.ip6c_cmdarg = (void *)¬ifymtu; 1095 } 1096 1097 ctlfunc = (void (*) __P((int, struct sockaddr *, void *))) 1098 (inet6sw[ip6_protox[nxt]].pr_ctlinput); 1099 if (ctlfunc) { 1100 (void) (*ctlfunc)(code, (struct sockaddr *)&icmp6dst, 1101 &ip6cp); 1102 } 1103 } 1104 return (0); 1105 1106 freeit: 1107 m_freem(m); 1108 return (-1); 1109 } 1110 1111 void 1112 icmp6_mtudisc_update(ip6cp, validated) 1113 struct ip6ctlparam *ip6cp; 1114 int validated; 1115 { 1116 unsigned long rtcount; 1117 struct icmp6_mtudisc_callback *mc; 1118 struct in6_addr *dst = ip6cp->ip6c_finaldst; 1119 struct icmp6_hdr *icmp6 = ip6cp->ip6c_icmp6; 1120 struct mbuf *m = ip6cp->ip6c_m; /* will be necessary for scope issue */ 1121 u_int mtu = ntohl(icmp6->icmp6_mtu); 1122 struct rtentry *rt = NULL; 1123 struct sockaddr_in6 sin6; 1124 1125 /* 1126 * allow non-validated cases if memory is plenty, to make traffic 1127 * from non-connected pcb happy. 1128 */ 1129 rtcount = rt_timer_count(icmp6_mtudisc_timeout_q); 1130 if (validated) { 1131 if (0 <= icmp6_mtudisc_hiwat && rtcount > icmp6_mtudisc_hiwat) 1132 return; 1133 else if (0 <= icmp6_mtudisc_lowat && 1134 rtcount > icmp6_mtudisc_lowat) { 1135 /* 1136 * XXX nuke a victim, install the new one. 1137 */ 1138 } 1139 } else { 1140 if (0 <= icmp6_mtudisc_lowat && rtcount > icmp6_mtudisc_lowat) 1141 return; 1142 } 1143 1144 bzero(&sin6, sizeof(sin6)); 1145 sin6.sin6_family = PF_INET6; 1146 sin6.sin6_len = sizeof(struct sockaddr_in6); 1147 sin6.sin6_addr = *dst; 1148 if (in6_setscope(&sin6.sin6_addr, m->m_pkthdr.rcvif, NULL)) 1149 return; 1150 1151 rt = icmp6_mtudisc_clone((struct sockaddr *)&sin6); 1152 1153 if (rt && (rt->rt_flags & RTF_HOST) && 1154 !(rt->rt_rmx.rmx_locks & RTV_MTU) && 1155 (rt->rt_rmx.rmx_mtu > mtu || rt->rt_rmx.rmx_mtu == 0)) { 1156 if (mtu < IN6_LINKMTU(rt->rt_ifp)) { 1157 icmp6stat.icp6s_pmtuchg++; 1158 rt->rt_rmx.rmx_mtu = mtu; 1159 } 1160 } 1161 if (rt) { /* XXX: need braces to avoid conflict with else in RTFREE. */ 1162 RTFREE(rt); 1163 } 1164 1165 /* 1166 * Notify protocols that the MTU for this destination 1167 * has changed. 1168 */ 1169 for (mc = LIST_FIRST(&icmp6_mtudisc_callbacks); mc != NULL; 1170 mc = LIST_NEXT(mc, mc_list)) 1171 (*mc->mc_func)(&sin6.sin6_addr); 1172 } 1173 1174 /* 1175 * Process a Node Information Query packet, based on 1176 * draft-ietf-ipngwg-icmp-name-lookups-07. 1177 * 1178 * Spec incompatibilities: 1179 * - IPv6 Subject address handling 1180 * - IPv4 Subject address handling support missing 1181 * - Proxy reply (answer even if it's not for me) 1182 * - joins NI group address at in6_ifattach() time only, does not cope 1183 * with hostname changes by sethostname(3) 1184 */ 1185 #ifndef offsetof /* XXX */ 1186 #define offsetof(type, member) ((size_t)(&((type *)0)->member)) 1187 #endif 1188 static struct mbuf * 1189 ni6_input(m, off) 1190 struct mbuf *m; 1191 int off; 1192 { 1193 struct icmp6_nodeinfo *ni6, *nni6; 1194 struct mbuf *n = NULL; 1195 u_int16_t qtype; 1196 int subjlen; 1197 int replylen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo); 1198 struct ni_reply_fqdn *fqdn; 1199 int addrs; /* for NI_QTYPE_NODEADDR */ 1200 struct ifnet *ifp = NULL; /* for NI_QTYPE_NODEADDR */ 1201 struct sockaddr_in6 sin6; /* ip6_dst */ 1202 struct in6_addr in6_subj; /* subject address */ 1203 struct ip6_hdr *ip6; 1204 int oldfqdn = 0; /* if 1, return pascal string (03 draft) */ 1205 char *subj = NULL; 1206 1207 ip6 = mtod(m, struct ip6_hdr *); 1208 IP6_EXTHDR_GET(ni6, struct icmp6_nodeinfo *, m, off, sizeof(*ni6)); 1209 if (ni6 == NULL) { 1210 /* m is already reclaimed */ 1211 return NULL; 1212 } 1213 1214 /* 1215 * Validate IPv6 destination address. 1216 * 1217 * The Responder must discard the Query without further processing 1218 * unless it is one of the Responder's unicast or anycast addresses, or 1219 * a link-local scope multicast address which the Responder has joined. 1220 * [icmp-name-lookups-07, Section 4.] 1221 */ 1222 bzero(&sin6, sizeof(sin6)); 1223 sin6.sin6_family = AF_INET6; 1224 sin6.sin6_len = sizeof(struct sockaddr_in6); 1225 bcopy(&ip6->ip6_dst, &sin6.sin6_addr, sizeof(sin6.sin6_addr)); 1226 /* XXX scopeid */ 1227 if (ifa_ifwithaddr((struct sockaddr *)&sin6)) 1228 ; /* unicast/anycast, fine */ 1229 else if (IN6_IS_ADDR_MC_LINKLOCAL(&sin6.sin6_addr)) 1230 ; /* link-local multicast, fine */ 1231 else 1232 goto bad; 1233 1234 /* validate query Subject field. */ 1235 qtype = ntohs(ni6->ni_qtype); 1236 subjlen = m->m_pkthdr.len - off - sizeof(struct icmp6_nodeinfo); 1237 switch (qtype) { 1238 case NI_QTYPE_NOOP: 1239 case NI_QTYPE_SUPTYPES: 1240 /* 07 draft */ 1241 if (ni6->ni_code == ICMP6_NI_SUBJ_FQDN && subjlen == 0) 1242 break; 1243 /* FALLTHROUGH */ 1244 case NI_QTYPE_FQDN: 1245 case NI_QTYPE_NODEADDR: 1246 switch (ni6->ni_code) { 1247 case ICMP6_NI_SUBJ_IPV6: 1248 #if ICMP6_NI_SUBJ_IPV6 != 0 1249 case 0: 1250 #endif 1251 /* 1252 * backward compatibility - try to accept 03 draft 1253 * format, where no Subject is present. 1254 */ 1255 if (qtype == NI_QTYPE_FQDN && ni6->ni_code == 0 && 1256 subjlen == 0) { 1257 oldfqdn++; 1258 break; 1259 } 1260 #if ICMP6_NI_SUBJ_IPV6 != 0 1261 if (ni6->ni_code != ICMP6_NI_SUBJ_IPV6) 1262 goto bad; 1263 #endif 1264 1265 if (subjlen != sizeof(sin6.sin6_addr)) 1266 goto bad; 1267 1268 /* 1269 * Validate Subject address. 1270 * 1271 * Not sure what exactly "address belongs to the node" 1272 * means in the spec, is it just unicast, or what? 1273 * 1274 * At this moment we consider Subject address as 1275 * "belong to the node" if the Subject address equals 1276 * to the IPv6 destination address; validation for 1277 * IPv6 destination address should have done enough 1278 * check for us. 1279 * 1280 * We do not do proxy at this moment. 1281 */ 1282 /* m_pulldown instead of copy? */ 1283 m_copydata(m, off + sizeof(struct icmp6_nodeinfo), 1284 subjlen, (caddr_t)&in6_subj); 1285 if (in6_setscope(&in6_subj, m->m_pkthdr.rcvif, NULL)) 1286 goto bad; 1287 1288 subj = (char *)&in6_subj; 1289 if (IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, &in6_subj)) 1290 break; 1291 1292 /* 1293 * XXX if we are to allow other cases, we should really 1294 * be careful about scope here. 1295 * basically, we should disallow queries toward IPv6 1296 * destination X with subject Y, if scope(X) > scope(Y). 1297 * if we allow scope(X) > scope(Y), it will result in 1298 * information leakage across scope boundary. 1299 */ 1300 goto bad; 1301 1302 case ICMP6_NI_SUBJ_FQDN: 1303 /* 1304 * Validate Subject name with gethostname(3). 1305 * 1306 * The behavior may need some debate, since: 1307 * - we are not sure if the node has FQDN as 1308 * hostname (returned by gethostname(3)). 1309 * - the code does wildcard match for truncated names. 1310 * however, we are not sure if we want to perform 1311 * wildcard match, if gethostname(3) side has 1312 * truncated hostname. 1313 */ 1314 n = ni6_nametodns(hostname, hostnamelen, 0); 1315 if (!n || n->m_next || n->m_len == 0) 1316 goto bad; 1317 IP6_EXTHDR_GET(subj, char *, m, 1318 off + sizeof(struct icmp6_nodeinfo), subjlen); 1319 if (subj == NULL) 1320 goto bad; 1321 if (!ni6_dnsmatch(subj, subjlen, mtod(n, const char *), 1322 n->m_len)) { 1323 goto bad; 1324 } 1325 m_freem(n); 1326 n = NULL; 1327 break; 1328 1329 case ICMP6_NI_SUBJ_IPV4: /* XXX: to be implemented? */ 1330 default: 1331 goto bad; 1332 } 1333 break; 1334 } 1335 1336 /* refuse based on configuration. XXX ICMP6_NI_REFUSED? */ 1337 switch (qtype) { 1338 case NI_QTYPE_FQDN: 1339 if ((icmp6_nodeinfo & 1) == 0) 1340 goto bad; 1341 break; 1342 case NI_QTYPE_NODEADDR: 1343 if ((icmp6_nodeinfo & 2) == 0) 1344 goto bad; 1345 break; 1346 } 1347 1348 /* guess reply length */ 1349 switch (qtype) { 1350 case NI_QTYPE_NOOP: 1351 break; /* no reply data */ 1352 case NI_QTYPE_SUPTYPES: 1353 replylen += sizeof(u_int32_t); 1354 break; 1355 case NI_QTYPE_FQDN: 1356 /* XXX will append an mbuf */ 1357 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1358 break; 1359 case NI_QTYPE_NODEADDR: 1360 addrs = ni6_addrs(ni6, m, &ifp, subj); 1361 if ((replylen += addrs * (sizeof(struct in6_addr) + 1362 sizeof(u_int32_t))) > MCLBYTES) 1363 replylen = MCLBYTES; /* XXX: will truncate pkt later */ 1364 break; 1365 default: 1366 /* 1367 * XXX: We must return a reply with the ICMP6 code 1368 * `unknown Qtype' in this case. However we regard the case 1369 * as an FQDN query for backward compatibility. 1370 * Older versions set a random value to this field, 1371 * so it rarely varies in the defined qtypes. 1372 * But the mechanism is not reliable... 1373 * maybe we should obsolete older versions. 1374 */ 1375 qtype = NI_QTYPE_FQDN; 1376 /* XXX will append an mbuf */ 1377 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1378 oldfqdn++; 1379 break; 1380 } 1381 1382 /* allocate an mbuf to reply. */ 1383 MGETHDR(n, M_DONTWAIT, m->m_type); 1384 if (n == NULL) { 1385 m_freem(m); 1386 return (NULL); 1387 } 1388 M_MOVE_PKTHDR(n, m); /* just for rcvif */ 1389 if (replylen > MHLEN) { 1390 if (replylen > MCLBYTES) { 1391 /* 1392 * XXX: should we try to allocate more? But MCLBYTES 1393 * is probably much larger than IPV6_MMTU... 1394 */ 1395 goto bad; 1396 } 1397 MCLGET(n, M_DONTWAIT); 1398 if ((n->m_flags & M_EXT) == 0) { 1399 goto bad; 1400 } 1401 } 1402 n->m_pkthdr.len = n->m_len = replylen; 1403 1404 /* copy mbuf header and IPv6 + Node Information base headers */ 1405 bcopy(mtod(m, caddr_t), mtod(n, caddr_t), sizeof(struct ip6_hdr)); 1406 nni6 = (struct icmp6_nodeinfo *)(mtod(n, struct ip6_hdr *) + 1); 1407 bcopy((caddr_t)ni6, (caddr_t)nni6, sizeof(struct icmp6_nodeinfo)); 1408 1409 /* qtype dependent procedure */ 1410 switch (qtype) { 1411 case NI_QTYPE_NOOP: 1412 nni6->ni_code = ICMP6_NI_SUCCESS; 1413 nni6->ni_flags = 0; 1414 break; 1415 case NI_QTYPE_SUPTYPES: 1416 { 1417 u_int32_t v; 1418 nni6->ni_code = ICMP6_NI_SUCCESS; 1419 nni6->ni_flags = htons(0x0000); /* raw bitmap */ 1420 /* supports NOOP, SUPTYPES, FQDN, and NODEADDR */ 1421 v = (u_int32_t)htonl(0x0000000f); 1422 bcopy(&v, nni6 + 1, sizeof(u_int32_t)); 1423 break; 1424 } 1425 case NI_QTYPE_FQDN: 1426 nni6->ni_code = ICMP6_NI_SUCCESS; 1427 fqdn = (struct ni_reply_fqdn *)(mtod(n, caddr_t) + 1428 sizeof(struct ip6_hdr) + 1429 sizeof(struct icmp6_nodeinfo)); 1430 nni6->ni_flags = 0; /* XXX: meaningless TTL */ 1431 fqdn->ni_fqdn_ttl = 0; /* ditto. */ 1432 /* 1433 * XXX do we really have FQDN in variable "hostname"? 1434 */ 1435 n->m_next = ni6_nametodns(hostname, hostnamelen, oldfqdn); 1436 if (n->m_next == NULL) 1437 goto bad; 1438 /* XXX we assume that n->m_next is not a chain */ 1439 if (n->m_next->m_next != NULL) 1440 goto bad; 1441 n->m_pkthdr.len += n->m_next->m_len; 1442 break; 1443 case NI_QTYPE_NODEADDR: 1444 { 1445 int lenlim, copied; 1446 1447 nni6->ni_code = ICMP6_NI_SUCCESS; 1448 n->m_pkthdr.len = n->m_len = 1449 sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo); 1450 lenlim = M_TRAILINGSPACE(n); 1451 copied = ni6_store_addrs(ni6, nni6, ifp, lenlim); 1452 /* XXX: reset mbuf length */ 1453 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) + 1454 sizeof(struct icmp6_nodeinfo) + copied; 1455 break; 1456 } 1457 default: 1458 break; /* XXX impossible! */ 1459 } 1460 1461 nni6->ni_type = ICMP6_NI_REPLY; 1462 m_freem(m); 1463 return (n); 1464 1465 bad: 1466 m_freem(m); 1467 if (n) 1468 m_freem(n); 1469 return (NULL); 1470 } 1471 #undef hostnamelen 1472 1473 #define isupper(x) ('A' <= (x) && (x) <= 'Z') 1474 #define isalpha(x) (('A' <= (x) && (x) <= 'Z') || ('a' <= (x) && (x) <= 'z')) 1475 #define isalnum(x) (isalpha(x) || ('0' <= (x) && (x) <= '9')) 1476 #define tolower(x) (isupper(x) ? (x) + 'a' - 'A' : (x)) 1477 1478 /* 1479 * make a mbuf with DNS-encoded string. no compression support. 1480 * 1481 * XXX names with less than 2 dots (like "foo" or "foo.section") will be 1482 * treated as truncated name (two \0 at the end). this is a wild guess. 1483 */ 1484 static struct mbuf * 1485 ni6_nametodns(name, namelen, old) 1486 const char *name; 1487 int namelen; 1488 int old; /* return pascal string if non-zero */ 1489 { 1490 struct mbuf *m; 1491 char *cp, *ep; 1492 const char *p, *q; 1493 int i, len, nterm; 1494 1495 if (old) 1496 len = namelen + 1; 1497 else 1498 len = MCLBYTES; 1499 1500 /* because MAXHOSTNAMELEN is usually 256, we use cluster mbuf */ 1501 MGET(m, M_DONTWAIT, MT_DATA); 1502 if (m && len > MLEN) { 1503 MCLGET(m, M_DONTWAIT); 1504 if ((m->m_flags & M_EXT) == 0) 1505 goto fail; 1506 } 1507 if (!m) 1508 goto fail; 1509 m->m_next = NULL; 1510 1511 if (old) { 1512 m->m_len = len; 1513 *mtod(m, char *) = namelen; 1514 bcopy(name, mtod(m, char *) + 1, namelen); 1515 return m; 1516 } else { 1517 m->m_len = 0; 1518 cp = mtod(m, char *); 1519 ep = mtod(m, char *) + M_TRAILINGSPACE(m); 1520 1521 /* if not certain about my name, return empty buffer */ 1522 if (namelen == 0) 1523 return m; 1524 1525 /* 1526 * guess if it looks like shortened hostname, or FQDN. 1527 * shortened hostname needs two trailing "\0". 1528 */ 1529 i = 0; 1530 for (p = name; p < name + namelen; p++) { 1531 if (*p && *p == '.') 1532 i++; 1533 } 1534 if (i < 2) 1535 nterm = 2; 1536 else 1537 nterm = 1; 1538 1539 p = name; 1540 while (cp < ep && p < name + namelen) { 1541 i = 0; 1542 for (q = p; q < name + namelen && *q && *q != '.'; q++) 1543 i++; 1544 /* result does not fit into mbuf */ 1545 if (cp + i + 1 >= ep) 1546 goto fail; 1547 /* 1548 * DNS label length restriction, RFC1035 page 8. 1549 * "i == 0" case is included here to avoid returning 1550 * 0-length label on "foo..bar". 1551 */ 1552 if (i <= 0 || i >= 64) 1553 goto fail; 1554 *cp++ = i; 1555 if (!isalpha(p[0]) || !isalnum(p[i - 1])) 1556 goto fail; 1557 while (i > 0) { 1558 if (!isalnum(*p) && *p != '-') 1559 goto fail; 1560 if (isupper(*p)) { 1561 *cp++ = tolower(*p); 1562 p++; 1563 } else 1564 *cp++ = *p++; 1565 i--; 1566 } 1567 p = q; 1568 if (p < name + namelen && *p == '.') 1569 p++; 1570 } 1571 /* termination */ 1572 if (cp + nterm >= ep) 1573 goto fail; 1574 while (nterm-- > 0) 1575 *cp++ = '\0'; 1576 m->m_len = cp - mtod(m, char *); 1577 return m; 1578 } 1579 1580 panic("should not reach here"); 1581 /* NOTREACHED */ 1582 1583 fail: 1584 if (m) 1585 m_freem(m); 1586 return NULL; 1587 } 1588 1589 /* 1590 * check if two DNS-encoded string matches. takes care of truncated 1591 * form (with \0\0 at the end). no compression support. 1592 * XXX upper/lowercase match (see RFC2065) 1593 */ 1594 static int 1595 ni6_dnsmatch(a, alen, b, blen) 1596 const char *a; 1597 int alen; 1598 const char *b; 1599 int blen; 1600 { 1601 const char *a0, *b0; 1602 int l; 1603 1604 /* simplest case - need validation? */ 1605 if (alen == blen && bcmp(a, b, alen) == 0) 1606 return 1; 1607 1608 a0 = a; 1609 b0 = b; 1610 1611 /* termination is mandatory */ 1612 if (alen < 2 || blen < 2) 1613 return 0; 1614 if (a0[alen - 1] != '\0' || b0[blen - 1] != '\0') 1615 return 0; 1616 alen--; 1617 blen--; 1618 1619 while (a - a0 < alen && b - b0 < blen) { 1620 if (a - a0 + 1 > alen || b - b0 + 1 > blen) 1621 return 0; 1622 1623 if ((signed char)a[0] < 0 || (signed char)b[0] < 0) 1624 return 0; 1625 /* we don't support compression yet */ 1626 if (a[0] >= 64 || b[0] >= 64) 1627 return 0; 1628 1629 /* truncated case */ 1630 if (a[0] == 0 && a - a0 == alen - 1) 1631 return 1; 1632 if (b[0] == 0 && b - b0 == blen - 1) 1633 return 1; 1634 if (a[0] == 0 || b[0] == 0) 1635 return 0; 1636 1637 if (a[0] != b[0]) 1638 return 0; 1639 l = a[0]; 1640 if (a - a0 + 1 + l > alen || b - b0 + 1 + l > blen) 1641 return 0; 1642 if (bcmp(a + 1, b + 1, l) != 0) 1643 return 0; 1644 1645 a += 1 + l; 1646 b += 1 + l; 1647 } 1648 1649 if (a - a0 == alen && b - b0 == blen) 1650 return 1; 1651 else 1652 return 0; 1653 } 1654 1655 /* 1656 * calculate the number of addresses to be returned in the node info reply. 1657 */ 1658 static int 1659 ni6_addrs(ni6, m, ifpp, subj) 1660 struct icmp6_nodeinfo *ni6; 1661 struct mbuf *m; 1662 struct ifnet **ifpp; 1663 char *subj; 1664 { 1665 struct ifnet *ifp; 1666 struct in6_ifaddr *ifa6; 1667 struct ifaddr *ifa; 1668 struct sockaddr_in6 *subj_ip6 = NULL; /* XXX pedant */ 1669 int addrs = 0, addrsofif, iffound = 0; 1670 int niflags = ni6->ni_flags; 1671 1672 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0) { 1673 switch (ni6->ni_code) { 1674 case ICMP6_NI_SUBJ_IPV6: 1675 if (subj == NULL) /* must be impossible... */ 1676 return (0); 1677 subj_ip6 = (struct sockaddr_in6 *)subj; 1678 break; 1679 default: 1680 /* 1681 * XXX: we only support IPv6 subject address for 1682 * this Qtype. 1683 */ 1684 return (0); 1685 } 1686 } 1687 1688 for (ifp = TAILQ_FIRST(&ifnet); ifp; ifp = TAILQ_NEXT(ifp, if_list)) 1689 { 1690 addrsofif = 0; 1691 for (ifa = ifp->if_addrlist.tqh_first; ifa; 1692 ifa = ifa->ifa_list.tqe_next) 1693 { 1694 if (ifa->ifa_addr->sa_family != AF_INET6) 1695 continue; 1696 ifa6 = (struct in6_ifaddr *)ifa; 1697 1698 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0 && 1699 IN6_ARE_ADDR_EQUAL(&subj_ip6->sin6_addr, 1700 &ifa6->ia_addr.sin6_addr)) 1701 iffound = 1; 1702 1703 /* 1704 * IPv4-mapped addresses can only be returned by a 1705 * Node Information proxy, since they represent 1706 * addresses of IPv4-only nodes, which perforce do 1707 * not implement this protocol. 1708 * [icmp-name-lookups-07, Section 5.4] 1709 * So we don't support NI_NODEADDR_FLAG_COMPAT in 1710 * this function at this moment. 1711 */ 1712 1713 /* What do we have to do about ::1? */ 1714 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1715 case IPV6_ADDR_SCOPE_LINKLOCAL: 1716 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0) 1717 continue; 1718 break; 1719 case IPV6_ADDR_SCOPE_SITELOCAL: 1720 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0) 1721 continue; 1722 break; 1723 case IPV6_ADDR_SCOPE_GLOBAL: 1724 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0) 1725 continue; 1726 break; 1727 default: 1728 continue; 1729 } 1730 1731 /* 1732 * check if anycast is okay. 1733 * XXX: just experimental. not in the spec. 1734 */ 1735 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 && 1736 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0) 1737 continue; /* we need only unicast addresses */ 1738 1739 addrsofif++; /* count the address */ 1740 } 1741 if (iffound) { 1742 *ifpp = ifp; 1743 return (addrsofif); 1744 } 1745 1746 addrs += addrsofif; 1747 } 1748 1749 return (addrs); 1750 } 1751 1752 static int 1753 ni6_store_addrs(ni6, nni6, ifp0, resid) 1754 struct icmp6_nodeinfo *ni6, *nni6; 1755 struct ifnet *ifp0; 1756 int resid; 1757 { 1758 struct ifnet *ifp = ifp0 ? ifp0 : TAILQ_FIRST(&ifnet); 1759 struct in6_ifaddr *ifa6; 1760 struct ifaddr *ifa; 1761 struct ifnet *ifp_dep = NULL; 1762 int copied = 0, allow_deprecated = 0; 1763 u_char *cp = (u_char *)(nni6 + 1); 1764 int niflags = ni6->ni_flags; 1765 u_int32_t ltime; 1766 1767 if (ifp0 == NULL && !(niflags & NI_NODEADDR_FLAG_ALL)) 1768 return (0); /* needless to copy */ 1769 1770 again: 1771 1772 for (; ifp; ifp = TAILQ_NEXT(ifp, if_list)) 1773 { 1774 for (ifa = ifp->if_addrlist.tqh_first; ifa; 1775 ifa = ifa->ifa_list.tqe_next) 1776 { 1777 if (ifa->ifa_addr->sa_family != AF_INET6) 1778 continue; 1779 ifa6 = (struct in6_ifaddr *)ifa; 1780 1781 if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) != 0 && 1782 allow_deprecated == 0) { 1783 /* 1784 * prefererred address should be put before 1785 * deprecated addresses. 1786 */ 1787 1788 /* record the interface for later search */ 1789 if (ifp_dep == NULL) 1790 ifp_dep = ifp; 1791 1792 continue; 1793 } 1794 else if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) == 0 && 1795 allow_deprecated != 0) 1796 continue; /* we now collect deprecated addrs */ 1797 1798 /* What do we have to do about ::1? */ 1799 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1800 case IPV6_ADDR_SCOPE_LINKLOCAL: 1801 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0) 1802 continue; 1803 break; 1804 case IPV6_ADDR_SCOPE_SITELOCAL: 1805 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0) 1806 continue; 1807 break; 1808 case IPV6_ADDR_SCOPE_GLOBAL: 1809 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0) 1810 continue; 1811 break; 1812 default: 1813 continue; 1814 } 1815 1816 /* 1817 * check if anycast is okay. 1818 * XXX: just experimental. not in the spec. 1819 */ 1820 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 && 1821 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0) 1822 continue; 1823 1824 /* now we can copy the address */ 1825 if (resid < sizeof(struct in6_addr) + 1826 sizeof(u_int32_t)) { 1827 /* 1828 * We give up much more copy. 1829 * Set the truncate flag and return. 1830 */ 1831 nni6->ni_flags |= 1832 NI_NODEADDR_FLAG_TRUNCATE; 1833 return (copied); 1834 } 1835 1836 /* 1837 * Set the TTL of the address. 1838 * The TTL value should be one of the following 1839 * according to the specification: 1840 * 1841 * 1. The remaining lifetime of a DHCP lease on the 1842 * address, or 1843 * 2. The remaining Valid Lifetime of a prefix from 1844 * which the address was derived through Stateless 1845 * Autoconfiguration. 1846 * 1847 * Note that we currently do not support stateful 1848 * address configuration by DHCPv6, so the former 1849 * case can't happen. 1850 * 1851 * TTL must be 2^31 > TTL >= 0. 1852 */ 1853 if (ifa6->ia6_lifetime.ia6t_expire == 0) 1854 ltime = ND6_INFINITE_LIFETIME; 1855 else { 1856 if (ifa6->ia6_lifetime.ia6t_expire > 1857 time_second) 1858 ltime = ifa6->ia6_lifetime.ia6t_expire - 1859 time_second; 1860 else 1861 ltime = 0; 1862 } 1863 if (ltime > 0x7fffffff) 1864 ltime = 0x7fffffff; 1865 ltime = htonl(ltime); 1866 1867 bcopy(<ime, cp, sizeof(u_int32_t)); 1868 cp += sizeof(u_int32_t); 1869 1870 /* copy the address itself */ 1871 bcopy(&ifa6->ia_addr.sin6_addr, cp, 1872 sizeof(struct in6_addr)); 1873 in6_clearscope((struct in6_addr *)cp); /* XXX */ 1874 cp += sizeof(struct in6_addr); 1875 1876 resid -= (sizeof(struct in6_addr) + sizeof(u_int32_t)); 1877 copied += (sizeof(struct in6_addr) + 1878 sizeof(u_int32_t)); 1879 } 1880 if (ifp0) /* we need search only on the specified IF */ 1881 break; 1882 } 1883 1884 if (allow_deprecated == 0 && ifp_dep != NULL) { 1885 ifp = ifp_dep; 1886 allow_deprecated = 1; 1887 1888 goto again; 1889 } 1890 1891 return (copied); 1892 } 1893 1894 /* 1895 * XXX almost dup'ed code with rip6_input. 1896 */ 1897 static int 1898 icmp6_rip6_input(mp, off) 1899 struct mbuf **mp; 1900 int off; 1901 { 1902 struct mbuf *m = *mp; 1903 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1904 struct inpcb_hdr *inph; 1905 struct in6pcb *in6p; 1906 struct in6pcb *last = NULL; 1907 struct sockaddr_in6 rip6src; 1908 struct icmp6_hdr *icmp6; 1909 struct mbuf *opts = NULL; 1910 1911 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 1912 if (icmp6 == NULL) { 1913 /* m is already reclaimed */ 1914 return IPPROTO_DONE; 1915 } 1916 1917 /* 1918 * XXX: the address may have embedded scope zone ID, which should be 1919 * hidden from applications. 1920 */ 1921 bzero(&rip6src, sizeof(rip6src)); 1922 rip6src.sin6_len = sizeof(struct sockaddr_in6); 1923 rip6src.sin6_family = AF_INET6; 1924 rip6src.sin6_addr = ip6->ip6_src; 1925 if (sa6_recoverscope(&rip6src)) { 1926 m_freem(m); 1927 return (IPPROTO_DONE); 1928 } 1929 1930 CIRCLEQ_FOREACH(inph, &raw6cbtable.inpt_queue, inph_queue) { 1931 in6p = (struct in6pcb *)inph; 1932 if (in6p->in6p_af != AF_INET6) 1933 continue; 1934 if (in6p->in6p_ip6.ip6_nxt != IPPROTO_ICMPV6) 1935 continue; 1936 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr) && 1937 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr, &ip6->ip6_dst)) 1938 continue; 1939 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr) && 1940 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr, &ip6->ip6_src)) 1941 continue; 1942 if (in6p->in6p_icmp6filt 1943 && ICMP6_FILTER_WILLBLOCK(icmp6->icmp6_type, 1944 in6p->in6p_icmp6filt)) 1945 continue; 1946 if (last) { 1947 struct mbuf *n; 1948 if ((n = m_copy(m, 0, (int)M_COPYALL)) != NULL) { 1949 if (last->in6p_flags & IN6P_CONTROLOPTS) 1950 ip6_savecontrol(last, &opts, ip6, n); 1951 /* strip intermediate headers */ 1952 m_adj(n, off); 1953 if (sbappendaddr(&last->in6p_socket->so_rcv, 1954 (struct sockaddr *)&rip6src, 1955 n, opts) == 0) { 1956 /* should notify about lost packet */ 1957 m_freem(n); 1958 if (opts) 1959 m_freem(opts); 1960 } else 1961 sorwakeup(last->in6p_socket); 1962 opts = NULL; 1963 } 1964 } 1965 last = in6p; 1966 } 1967 if (last) { 1968 if (last->in6p_flags & IN6P_CONTROLOPTS) 1969 ip6_savecontrol(last, &opts, ip6, m); 1970 /* strip intermediate headers */ 1971 m_adj(m, off); 1972 if (sbappendaddr(&last->in6p_socket->so_rcv, 1973 (struct sockaddr *)&rip6src, m, opts) == 0) { 1974 m_freem(m); 1975 if (opts) 1976 m_freem(opts); 1977 } else 1978 sorwakeup(last->in6p_socket); 1979 } else { 1980 m_freem(m); 1981 ip6stat.ip6s_delivered--; 1982 } 1983 return IPPROTO_DONE; 1984 } 1985 1986 /* 1987 * Reflect the ip6 packet back to the source. 1988 * OFF points to the icmp6 header, counted from the top of the mbuf. 1989 * 1990 * Note: RFC 1885 required that an echo reply should be truncated if it 1991 * did not fit in with (return) path MTU, and KAME code supported the 1992 * behavior. However, as a clarification after the RFC, this limitation 1993 * was removed in a revised version of the spec, RFC 2463. We had kept the 1994 * old behavior, with a (non-default) ifdef block, while the new version of 1995 * the spec was an internet-draft status, and even after the new RFC was 1996 * published. But it would rather make sense to clean the obsoleted part 1997 * up, and to make the code simpler at this stage. 1998 */ 1999 void 2000 icmp6_reflect(m, off) 2001 struct mbuf *m; 2002 size_t off; 2003 { 2004 struct ip6_hdr *ip6; 2005 struct icmp6_hdr *icmp6; 2006 struct in6_ifaddr *ia; 2007 int plen; 2008 int type, code; 2009 struct ifnet *outif = NULL; 2010 struct in6_addr origdst, *src = NULL; 2011 2012 /* too short to reflect */ 2013 if (off < sizeof(struct ip6_hdr)) { 2014 nd6log((LOG_DEBUG, 2015 "sanity fail: off=%lx, sizeof(ip6)=%lx in %s:%d\n", 2016 (u_long)off, (u_long)sizeof(struct ip6_hdr), 2017 __FILE__, __LINE__)); 2018 goto bad; 2019 } 2020 2021 /* 2022 * If there are extra headers between IPv6 and ICMPv6, strip 2023 * off that header first. 2024 */ 2025 #ifdef DIAGNOSTIC 2026 if (sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) > MHLEN) 2027 panic("assumption failed in icmp6_reflect"); 2028 #endif 2029 if (off > sizeof(struct ip6_hdr)) { 2030 size_t l; 2031 struct ip6_hdr nip6; 2032 2033 l = off - sizeof(struct ip6_hdr); 2034 m_copydata(m, 0, sizeof(nip6), (caddr_t)&nip6); 2035 m_adj(m, l); 2036 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 2037 if (m->m_len < l) { 2038 if ((m = m_pullup(m, l)) == NULL) 2039 return; 2040 } 2041 bcopy((caddr_t)&nip6, mtod(m, caddr_t), sizeof(nip6)); 2042 } else /* off == sizeof(struct ip6_hdr) */ { 2043 size_t l; 2044 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 2045 if (m->m_len < l) { 2046 if ((m = m_pullup(m, l)) == NULL) 2047 return; 2048 } 2049 } 2050 plen = m->m_pkthdr.len - sizeof(struct ip6_hdr); 2051 ip6 = mtod(m, struct ip6_hdr *); 2052 ip6->ip6_nxt = IPPROTO_ICMPV6; 2053 icmp6 = (struct icmp6_hdr *)(ip6 + 1); 2054 type = icmp6->icmp6_type; /* keep type for statistics */ 2055 code = icmp6->icmp6_code; /* ditto. */ 2056 2057 origdst = ip6->ip6_dst; 2058 /* 2059 * ip6_input() drops a packet if its src is multicast. 2060 * So, the src is never multicast. 2061 */ 2062 ip6->ip6_dst = ip6->ip6_src; 2063 2064 /* 2065 * If the incoming packet was addressed directly to us (i.e. unicast), 2066 * use dst as the src for the reply. 2067 * The IN6_IFF_NOTREADY case would be VERY rare, but is possible 2068 * (for example) when we encounter an error while forwarding procedure 2069 * destined to a duplicated address of ours. 2070 * Note that ip6_getdstifaddr() may fail if we are in an error handling 2071 * procedure of an outgoing packet of our own, in which case we need 2072 * to search in the ifaddr list. 2073 */ 2074 if (!IN6_IS_ADDR_MULTICAST(&origdst)) { 2075 if ((ia = ip6_getdstifaddr(m))) { 2076 if (!(ia->ia6_flags & 2077 (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY))) 2078 src = &ia->ia_addr.sin6_addr; 2079 } else { 2080 struct sockaddr_in6 d; 2081 2082 bzero(&d, sizeof(d)); 2083 d.sin6_family = AF_INET6; 2084 d.sin6_len = sizeof(d); 2085 d.sin6_addr = origdst; 2086 ia = (struct in6_ifaddr *) 2087 ifa_ifwithaddr((struct sockaddr *)&d); 2088 if (ia && 2089 !(ia->ia6_flags & 2090 (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY))) { 2091 src = &ia->ia_addr.sin6_addr; 2092 } 2093 } 2094 } 2095 2096 if (src == NULL) { 2097 int e; 2098 struct sockaddr_in6 sin6; 2099 struct route_in6 ro; 2100 2101 /* 2102 * This case matches to multicasts, our anycast, or unicasts 2103 * that we do not own. Select a source address based on the 2104 * source address of the erroneous packet. 2105 */ 2106 bzero(&sin6, sizeof(sin6)); 2107 sin6.sin6_family = AF_INET6; 2108 sin6.sin6_len = sizeof(sin6); 2109 sin6.sin6_addr = ip6->ip6_dst; /* zone ID should be embedded */ 2110 2111 bzero(&ro, sizeof(ro)); 2112 src = in6_selectsrc(&sin6, NULL, NULL, &ro, NULL, &outif, &e); 2113 if (ro.ro_rt) { /* XXX: see comments in icmp6_mtudisc_update */ 2114 RTFREE(ro.ro_rt); /* XXX: we could use this */ 2115 } 2116 if (src == NULL) { 2117 nd6log((LOG_DEBUG, 2118 "icmp6_reflect: source can't be determined: " 2119 "dst=%s, error=%d\n", 2120 ip6_sprintf(&sin6.sin6_addr), e)); 2121 goto bad; 2122 } 2123 } 2124 2125 ip6->ip6_src = *src; 2126 ip6->ip6_flow = 0; 2127 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2128 ip6->ip6_vfc |= IPV6_VERSION; 2129 ip6->ip6_nxt = IPPROTO_ICMPV6; 2130 if (m->m_pkthdr.rcvif) { 2131 /* XXX: This may not be the outgoing interface */ 2132 ip6->ip6_hlim = ND_IFINFO(m->m_pkthdr.rcvif)->chlim; 2133 } else 2134 ip6->ip6_hlim = ip6_defhlim; 2135 2136 icmp6->icmp6_cksum = 0; 2137 icmp6->icmp6_cksum = in6_cksum(m, IPPROTO_ICMPV6, 2138 sizeof(struct ip6_hdr), plen); 2139 2140 /* 2141 * XXX option handling 2142 */ 2143 2144 m->m_flags &= ~(M_BCAST|M_MCAST); 2145 2146 /* 2147 * To avoid a "too big" situation at an intermediate router 2148 * and the path MTU discovery process, specify the IPV6_MINMTU flag. 2149 * Note that only echo and node information replies are affected, 2150 * since the length of ICMP6 errors is limited to the minimum MTU. 2151 */ 2152 if (ip6_output(m, NULL, NULL, IPV6_MINMTU, 2153 (struct ip6_moptions *)NULL, (struct socket *)NULL, &outif) != 0 2154 && outif) 2155 icmp6_ifstat_inc(outif, ifs6_out_error); 2156 2157 if (outif) 2158 icmp6_ifoutstat_inc(outif, type, code); 2159 2160 return; 2161 2162 bad: 2163 m_freem(m); 2164 return; 2165 } 2166 2167 void 2168 icmp6_fasttimo() 2169 { 2170 2171 mld6_fasttimeo(); 2172 } 2173 2174 static const char * 2175 icmp6_redirect_diag(src6, dst6, tgt6) 2176 struct in6_addr *src6; 2177 struct in6_addr *dst6; 2178 struct in6_addr *tgt6; 2179 { 2180 static char buf[1024]; 2181 snprintf(buf, sizeof(buf), "(src=%s dst=%s tgt=%s)", 2182 ip6_sprintf(src6), ip6_sprintf(dst6), ip6_sprintf(tgt6)); 2183 return buf; 2184 } 2185 2186 void 2187 icmp6_redirect_input(m, off) 2188 struct mbuf *m; 2189 int off; 2190 { 2191 struct ifnet *ifp = m->m_pkthdr.rcvif; 2192 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 2193 struct nd_redirect *nd_rd; 2194 int icmp6len = ntohs(ip6->ip6_plen); 2195 char *lladdr = NULL; 2196 int lladdrlen = 0; 2197 struct rtentry *rt = NULL; 2198 int is_router; 2199 int is_onlink; 2200 struct in6_addr src6 = ip6->ip6_src; 2201 struct in6_addr redtgt6; 2202 struct in6_addr reddst6; 2203 union nd_opts ndopts; 2204 2205 if (!ifp) 2206 return; 2207 2208 /* XXX if we are router, we don't update route by icmp6 redirect */ 2209 if (ip6_forwarding) 2210 goto freeit; 2211 if (!icmp6_rediraccept) 2212 goto freeit; 2213 2214 IP6_EXTHDR_GET(nd_rd, struct nd_redirect *, m, off, icmp6len); 2215 if (nd_rd == NULL) { 2216 icmp6stat.icp6s_tooshort++; 2217 return; 2218 } 2219 redtgt6 = nd_rd->nd_rd_target; 2220 reddst6 = nd_rd->nd_rd_dst; 2221 2222 if (in6_setscope(&redtgt6, m->m_pkthdr.rcvif, NULL) || 2223 in6_setscope(&reddst6, m->m_pkthdr.rcvif, NULL)) { 2224 goto freeit; 2225 } 2226 2227 /* validation */ 2228 if (!IN6_IS_ADDR_LINKLOCAL(&src6)) { 2229 nd6log((LOG_ERR, 2230 "ICMP6 redirect sent from %s rejected; " 2231 "must be from linklocal\n", ip6_sprintf(&src6))); 2232 goto bad; 2233 } 2234 if (ip6->ip6_hlim != 255) { 2235 nd6log((LOG_ERR, 2236 "ICMP6 redirect sent from %s rejected; " 2237 "hlim=%d (must be 255)\n", 2238 ip6_sprintf(&src6), ip6->ip6_hlim)); 2239 goto bad; 2240 } 2241 { 2242 /* ip6->ip6_src must be equal to gw for icmp6->icmp6_reddst */ 2243 struct sockaddr_in6 sin6; 2244 struct in6_addr *gw6; 2245 2246 bzero(&sin6, sizeof(sin6)); 2247 sin6.sin6_family = AF_INET6; 2248 sin6.sin6_len = sizeof(struct sockaddr_in6); 2249 bcopy(&reddst6, &sin6.sin6_addr, sizeof(reddst6)); 2250 rt = rtalloc1((struct sockaddr *)&sin6, 0); 2251 if (rt) { 2252 if (rt->rt_gateway == NULL || 2253 rt->rt_gateway->sa_family != AF_INET6) { 2254 nd6log((LOG_ERR, 2255 "ICMP6 redirect rejected; no route " 2256 "with inet6 gateway found for redirect dst: %s\n", 2257 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2258 RTFREE(rt); 2259 goto bad; 2260 } 2261 2262 gw6 = &(((struct sockaddr_in6 *)rt->rt_gateway)->sin6_addr); 2263 if (bcmp(&src6, gw6, sizeof(struct in6_addr)) != 0) { 2264 nd6log((LOG_ERR, 2265 "ICMP6 redirect rejected; " 2266 "not equal to gw-for-src=%s (must be same): " 2267 "%s\n", 2268 ip6_sprintf(gw6), 2269 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2270 RTFREE(rt); 2271 goto bad; 2272 } 2273 } else { 2274 nd6log((LOG_ERR, 2275 "ICMP6 redirect rejected; " 2276 "no route found for redirect dst: %s\n", 2277 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2278 goto bad; 2279 } 2280 RTFREE(rt); 2281 rt = NULL; 2282 } 2283 if (IN6_IS_ADDR_MULTICAST(&reddst6)) { 2284 nd6log((LOG_ERR, 2285 "ICMP6 redirect rejected; " 2286 "redirect dst must be unicast: %s\n", 2287 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2288 goto bad; 2289 } 2290 2291 is_router = is_onlink = 0; 2292 if (IN6_IS_ADDR_LINKLOCAL(&redtgt6)) 2293 is_router = 1; /* router case */ 2294 if (bcmp(&redtgt6, &reddst6, sizeof(redtgt6)) == 0) 2295 is_onlink = 1; /* on-link destination case */ 2296 if (!is_router && !is_onlink) { 2297 nd6log((LOG_ERR, 2298 "ICMP6 redirect rejected; " 2299 "neither router case nor onlink case: %s\n", 2300 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2301 goto bad; 2302 } 2303 /* validation passed */ 2304 2305 icmp6len -= sizeof(*nd_rd); 2306 nd6_option_init(nd_rd + 1, icmp6len, &ndopts); 2307 if (nd6_options(&ndopts) < 0) { 2308 nd6log((LOG_INFO, "icmp6_redirect_input: " 2309 "invalid ND option, rejected: %s\n", 2310 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2311 /* nd6_options have incremented stats */ 2312 goto freeit; 2313 } 2314 2315 if (ndopts.nd_opts_tgt_lladdr) { 2316 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 2317 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 2318 } 2319 2320 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 2321 nd6log((LOG_INFO, 2322 "icmp6_redirect_input: lladdrlen mismatch for %s " 2323 "(if %d, icmp6 packet %d): %s\n", 2324 ip6_sprintf(&redtgt6), ifp->if_addrlen, lladdrlen - 2, 2325 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2326 goto bad; 2327 } 2328 2329 /* RFC 2461 8.3 */ 2330 nd6_cache_lladdr(ifp, &redtgt6, lladdr, lladdrlen, ND_REDIRECT, 2331 is_onlink ? ND_REDIRECT_ONLINK : ND_REDIRECT_ROUTER); 2332 2333 if (!is_onlink) { /* better router case. perform rtredirect. */ 2334 /* perform rtredirect */ 2335 struct sockaddr_in6 sdst; 2336 struct sockaddr_in6 sgw; 2337 struct sockaddr_in6 ssrc; 2338 unsigned long rtcount; 2339 struct rtentry *newrt = NULL; 2340 2341 /* 2342 * do not install redirect route, if the number of entries 2343 * is too much (> hiwat). note that, the node (= host) will 2344 * work just fine even if we do not install redirect route 2345 * (there will be additional hops, though). 2346 */ 2347 rtcount = rt_timer_count(icmp6_redirect_timeout_q); 2348 if (0 <= icmp6_redirect_hiwat && rtcount > icmp6_redirect_hiwat) 2349 return; 2350 else if (0 <= icmp6_redirect_lowat && 2351 rtcount > icmp6_redirect_lowat) { 2352 /* 2353 * XXX nuke a victim, install the new one. 2354 */ 2355 } 2356 2357 bzero(&sdst, sizeof(sdst)); 2358 bzero(&sgw, sizeof(sgw)); 2359 bzero(&ssrc, sizeof(ssrc)); 2360 sdst.sin6_family = sgw.sin6_family = ssrc.sin6_family = AF_INET6; 2361 sdst.sin6_len = sgw.sin6_len = ssrc.sin6_len = 2362 sizeof(struct sockaddr_in6); 2363 bcopy(&redtgt6, &sgw.sin6_addr, sizeof(struct in6_addr)); 2364 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2365 bcopy(&src6, &ssrc.sin6_addr, sizeof(struct in6_addr)); 2366 rtredirect((struct sockaddr *)&sdst, (struct sockaddr *)&sgw, 2367 (struct sockaddr *)NULL, RTF_GATEWAY | RTF_HOST, 2368 (struct sockaddr *)&ssrc, 2369 &newrt); 2370 2371 if (newrt) { 2372 (void)rt_timer_add(newrt, icmp6_redirect_timeout, 2373 icmp6_redirect_timeout_q); 2374 rtfree(newrt); 2375 } 2376 } 2377 /* finally update cached route in each socket via pfctlinput */ 2378 { 2379 struct sockaddr_in6 sdst; 2380 2381 bzero(&sdst, sizeof(sdst)); 2382 sdst.sin6_family = AF_INET6; 2383 sdst.sin6_len = sizeof(struct sockaddr_in6); 2384 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2385 pfctlinput(PRC_REDIRECT_HOST, (struct sockaddr *)&sdst); 2386 #ifdef IPSEC 2387 key_sa_routechange((struct sockaddr *)&sdst); 2388 #endif 2389 } 2390 2391 freeit: 2392 m_freem(m); 2393 return; 2394 2395 bad: 2396 icmp6stat.icp6s_badredirect++; 2397 m_freem(m); 2398 } 2399 2400 void 2401 icmp6_redirect_output(m0, rt) 2402 struct mbuf *m0; 2403 struct rtentry *rt; 2404 { 2405 struct ifnet *ifp; /* my outgoing interface */ 2406 struct in6_addr *ifp_ll6; 2407 struct in6_addr *nexthop; 2408 struct ip6_hdr *sip6; /* m0 as struct ip6_hdr */ 2409 struct mbuf *m = NULL; /* newly allocated one */ 2410 struct ip6_hdr *ip6; /* m as struct ip6_hdr */ 2411 struct nd_redirect *nd_rd; 2412 size_t maxlen; 2413 u_char *p; 2414 struct sockaddr_in6 src_sa; 2415 2416 icmp6_errcount(&icmp6stat.icp6s_outerrhist, ND_REDIRECT, 0); 2417 2418 /* if we are not router, we don't send icmp6 redirect */ 2419 if (!ip6_forwarding) 2420 goto fail; 2421 2422 /* sanity check */ 2423 if (!m0 || !rt || !(rt->rt_flags & RTF_UP) || !(ifp = rt->rt_ifp)) 2424 goto fail; 2425 2426 /* 2427 * Address check: 2428 * the source address must identify a neighbor, and 2429 * the destination address must not be a multicast address 2430 * [RFC 2461, sec 8.2] 2431 */ 2432 sip6 = mtod(m0, struct ip6_hdr *); 2433 bzero(&src_sa, sizeof(src_sa)); 2434 src_sa.sin6_family = AF_INET6; 2435 src_sa.sin6_len = sizeof(src_sa); 2436 src_sa.sin6_addr = sip6->ip6_src; 2437 if (nd6_is_addr_neighbor(&src_sa, ifp) == 0) 2438 goto fail; 2439 if (IN6_IS_ADDR_MULTICAST(&sip6->ip6_dst)) 2440 goto fail; /* what should we do here? */ 2441 2442 /* rate limit */ 2443 if (icmp6_ratelimit(&sip6->ip6_src, ND_REDIRECT, 0)) 2444 goto fail; 2445 2446 /* 2447 * Since we are going to append up to 1280 bytes (= IPV6_MMTU), 2448 * we almost always ask for an mbuf cluster for simplicity. 2449 * (MHLEN < IPV6_MMTU is almost always true) 2450 */ 2451 #if IPV6_MMTU >= MCLBYTES 2452 # error assumption failed about IPV6_MMTU and MCLBYTES 2453 #endif 2454 MGETHDR(m, M_DONTWAIT, MT_HEADER); 2455 if (m && IPV6_MMTU >= MHLEN) 2456 MCLGET(m, M_DONTWAIT); 2457 if (!m) 2458 goto fail; 2459 m->m_pkthdr.rcvif = NULL; 2460 m->m_len = 0; 2461 maxlen = M_TRAILINGSPACE(m); 2462 maxlen = min(IPV6_MMTU, maxlen); 2463 /* just for safety */ 2464 if (maxlen < sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) + 2465 ((sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7)) { 2466 goto fail; 2467 } 2468 2469 { 2470 /* get ip6 linklocal address for ifp(my outgoing interface). */ 2471 struct in6_ifaddr *ia; 2472 if ((ia = in6ifa_ifpforlinklocal(ifp, 2473 IN6_IFF_NOTREADY| 2474 IN6_IFF_ANYCAST)) == NULL) 2475 goto fail; 2476 ifp_ll6 = &ia->ia_addr.sin6_addr; 2477 } 2478 2479 /* get ip6 linklocal address for the router. */ 2480 if (rt->rt_gateway && (rt->rt_flags & RTF_GATEWAY)) { 2481 struct sockaddr_in6 *sin6; 2482 sin6 = (struct sockaddr_in6 *)rt->rt_gateway; 2483 nexthop = &sin6->sin6_addr; 2484 if (!IN6_IS_ADDR_LINKLOCAL(nexthop)) 2485 nexthop = NULL; 2486 } else 2487 nexthop = NULL; 2488 2489 /* ip6 */ 2490 ip6 = mtod(m, struct ip6_hdr *); 2491 ip6->ip6_flow = 0; 2492 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2493 ip6->ip6_vfc |= IPV6_VERSION; 2494 /* ip6->ip6_plen will be set later */ 2495 ip6->ip6_nxt = IPPROTO_ICMPV6; 2496 ip6->ip6_hlim = 255; 2497 /* ip6->ip6_src must be linklocal addr for my outgoing if. */ 2498 bcopy(ifp_ll6, &ip6->ip6_src, sizeof(struct in6_addr)); 2499 bcopy(&sip6->ip6_src, &ip6->ip6_dst, sizeof(struct in6_addr)); 2500 2501 /* ND Redirect */ 2502 nd_rd = (struct nd_redirect *)(ip6 + 1); 2503 nd_rd->nd_rd_type = ND_REDIRECT; 2504 nd_rd->nd_rd_code = 0; 2505 nd_rd->nd_rd_reserved = 0; 2506 if (rt->rt_flags & RTF_GATEWAY) { 2507 /* 2508 * nd_rd->nd_rd_target must be a link-local address in 2509 * better router cases. 2510 */ 2511 if (!nexthop) 2512 goto fail; 2513 bcopy(nexthop, &nd_rd->nd_rd_target, 2514 sizeof(nd_rd->nd_rd_target)); 2515 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2516 sizeof(nd_rd->nd_rd_dst)); 2517 } else { 2518 /* make sure redtgt == reddst */ 2519 nexthop = &sip6->ip6_dst; 2520 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_target, 2521 sizeof(nd_rd->nd_rd_target)); 2522 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2523 sizeof(nd_rd->nd_rd_dst)); 2524 } 2525 2526 p = (u_char *)(nd_rd + 1); 2527 2528 { 2529 /* target lladdr option */ 2530 struct rtentry *rt_nexthop = NULL; 2531 int len; 2532 struct sockaddr_dl *sdl; 2533 struct nd_opt_hdr *nd_opt; 2534 char *lladdr; 2535 2536 rt_nexthop = nd6_lookup(nexthop, 0, ifp); 2537 if (!rt_nexthop) 2538 goto nolladdropt; 2539 len = sizeof(*nd_opt) + ifp->if_addrlen; 2540 len = (len + 7) & ~7; /* round by 8 */ 2541 /* safety check */ 2542 if (len + (p - (u_char *)ip6) > maxlen) 2543 goto nolladdropt; 2544 if (!(rt_nexthop->rt_flags & RTF_GATEWAY) && 2545 (rt_nexthop->rt_flags & RTF_LLINFO) && 2546 (rt_nexthop->rt_gateway->sa_family == AF_LINK) && 2547 (sdl = (struct sockaddr_dl *)rt_nexthop->rt_gateway) && 2548 sdl->sdl_alen) { 2549 nd_opt = (struct nd_opt_hdr *)p; 2550 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 2551 nd_opt->nd_opt_len = len >> 3; 2552 lladdr = (char *)(nd_opt + 1); 2553 bcopy(LLADDR(sdl), lladdr, ifp->if_addrlen); 2554 p += len; 2555 } 2556 } 2557 nolladdropt:; 2558 2559 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2560 2561 /* just to be safe */ 2562 if (m0->m_flags & M_DECRYPTED) 2563 goto noredhdropt; 2564 if (p - (u_char *)ip6 > maxlen) 2565 goto noredhdropt; 2566 2567 { 2568 /* redirected header option */ 2569 int len; 2570 struct nd_opt_rd_hdr *nd_opt_rh; 2571 2572 /* 2573 * compute the maximum size for icmp6 redirect header option. 2574 * XXX room for auth header? 2575 */ 2576 len = maxlen - (p - (u_char *)ip6); 2577 len &= ~7; 2578 2579 /* 2580 * Redirected header option spec (RFC2461 4.6.3) talks nothing 2581 * about padding/truncate rule for the original IP packet. 2582 * From the discussion on IPv6imp in Feb 1999, 2583 * the consensus was: 2584 * - "attach as much as possible" is the goal 2585 * - pad if not aligned (original size can be guessed by 2586 * original ip6 header) 2587 * Following code adds the padding if it is simple enough, 2588 * and truncates if not. 2589 */ 2590 if (len - sizeof(*nd_opt_rh) < m0->m_pkthdr.len) { 2591 /* not enough room, truncate */ 2592 m_adj(m0, (len - sizeof(*nd_opt_rh)) - 2593 m0->m_pkthdr.len); 2594 } else { 2595 /* 2596 * enough room, truncate if not aligned. 2597 * we don't pad here for simplicity. 2598 */ 2599 size_t extra; 2600 2601 extra = m0->m_pkthdr.len % 8; 2602 if (extra) { 2603 /* truncate */ 2604 m_adj(m0, -extra); 2605 } 2606 len = m0->m_pkthdr.len + sizeof(*nd_opt_rh); 2607 } 2608 2609 nd_opt_rh = (struct nd_opt_rd_hdr *)p; 2610 bzero(nd_opt_rh, sizeof(*nd_opt_rh)); 2611 nd_opt_rh->nd_opt_rh_type = ND_OPT_REDIRECTED_HEADER; 2612 nd_opt_rh->nd_opt_rh_len = len >> 3; 2613 p += sizeof(*nd_opt_rh); 2614 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2615 2616 /* connect m0 to m */ 2617 m->m_pkthdr.len += m0->m_pkthdr.len; 2618 m_cat(m, m0); 2619 m0 = NULL; 2620 } 2621 noredhdropt: 2622 if (m0) { 2623 m_freem(m0); 2624 m0 = NULL; 2625 } 2626 2627 sip6 = mtod(m, struct ip6_hdr *); 2628 /* XXX: clear embedded link IDs in the inner header */ 2629 in6_clearscope(&sip6->ip6_src); 2630 in6_clearscope(&sip6->ip6_dst); 2631 in6_clearscope(&nd_rd->nd_rd_target); 2632 in6_clearscope(&nd_rd->nd_rd_dst); 2633 2634 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr)); 2635 2636 nd_rd->nd_rd_cksum = 0; 2637 nd_rd->nd_rd_cksum 2638 = in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), ntohs(ip6->ip6_plen)); 2639 2640 /* send the packet to outside... */ 2641 if (ip6_output(m, NULL, NULL, 0, 2642 (struct ip6_moptions *)NULL, (struct socket *)NULL, NULL) != 0) 2643 icmp6_ifstat_inc(ifp, ifs6_out_error); 2644 2645 icmp6_ifstat_inc(ifp, ifs6_out_msg); 2646 icmp6_ifstat_inc(ifp, ifs6_out_redirect); 2647 icmp6stat.icp6s_outhist[ND_REDIRECT]++; 2648 2649 return; 2650 2651 fail: 2652 if (m) 2653 m_freem(m); 2654 if (m0) 2655 m_freem(m0); 2656 } 2657 2658 /* 2659 * ICMPv6 socket option processing. 2660 */ 2661 int 2662 icmp6_ctloutput(op, so, level, optname, mp) 2663 int op; 2664 struct socket *so; 2665 int level, optname; 2666 struct mbuf **mp; 2667 { 2668 int error = 0; 2669 int optlen; 2670 struct in6pcb *in6p = sotoin6pcb(so); 2671 struct mbuf *m = *mp; 2672 2673 optlen = m ? m->m_len : 0; 2674 2675 if (level != IPPROTO_ICMPV6) { 2676 if (op == PRCO_SETOPT && m) 2677 (void)m_free(m); 2678 return EINVAL; 2679 } 2680 2681 switch (op) { 2682 case PRCO_SETOPT: 2683 switch (optname) { 2684 case ICMP6_FILTER: 2685 { 2686 struct icmp6_filter *p; 2687 2688 if (optlen != sizeof(*p)) { 2689 error = EMSGSIZE; 2690 break; 2691 } 2692 p = mtod(m, struct icmp6_filter *); 2693 if (!p || !in6p->in6p_icmp6filt) { 2694 error = EINVAL; 2695 break; 2696 } 2697 bcopy(p, in6p->in6p_icmp6filt, 2698 sizeof(struct icmp6_filter)); 2699 error = 0; 2700 break; 2701 } 2702 2703 default: 2704 error = ENOPROTOOPT; 2705 break; 2706 } 2707 if (m) 2708 (void)m_freem(m); 2709 break; 2710 2711 case PRCO_GETOPT: 2712 switch (optname) { 2713 case ICMP6_FILTER: 2714 { 2715 struct icmp6_filter *p; 2716 2717 if (!in6p->in6p_icmp6filt) { 2718 error = EINVAL; 2719 break; 2720 } 2721 *mp = m = m_get(M_WAIT, MT_SOOPTS); 2722 m->m_len = sizeof(struct icmp6_filter); 2723 p = mtod(m, struct icmp6_filter *); 2724 bcopy(in6p->in6p_icmp6filt, p, 2725 sizeof(struct icmp6_filter)); 2726 error = 0; 2727 break; 2728 } 2729 2730 default: 2731 error = ENOPROTOOPT; 2732 break; 2733 } 2734 break; 2735 } 2736 2737 return (error); 2738 } 2739 2740 /* 2741 * Perform rate limit check. 2742 * Returns 0 if it is okay to send the icmp6 packet. 2743 * Returns 1 if the router SHOULD NOT send this icmp6 packet due to rate 2744 * limitation. 2745 * 2746 * XXX per-destination/type check necessary? 2747 */ 2748 static int 2749 icmp6_ratelimit(dst, type, code) 2750 const struct in6_addr *dst; /* not used at this moment */ 2751 const int type; /* not used at this moment */ 2752 const int code; /* not used at this moment */ 2753 { 2754 int ret; 2755 2756 ret = 0; /* okay to send */ 2757 2758 /* PPS limit */ 2759 if (!ppsratecheck(&icmp6errppslim_last, &icmp6errpps_count, 2760 icmp6errppslim)) { 2761 /* The packet is subject to rate limit */ 2762 ret++; 2763 } 2764 2765 return ret; 2766 } 2767 2768 static struct rtentry * 2769 icmp6_mtudisc_clone(dst) 2770 struct sockaddr *dst; 2771 { 2772 struct rtentry *rt; 2773 int error; 2774 2775 rt = rtalloc1(dst, 1); 2776 if (rt == 0) 2777 return NULL; 2778 2779 /* If we didn't get a host route, allocate one */ 2780 if ((rt->rt_flags & RTF_HOST) == 0) { 2781 struct rtentry *nrt; 2782 2783 error = rtrequest((int) RTM_ADD, dst, 2784 (struct sockaddr *) rt->rt_gateway, 2785 (struct sockaddr *) 0, 2786 RTF_GATEWAY | RTF_HOST | RTF_DYNAMIC, &nrt); 2787 if (error) { 2788 rtfree(rt); 2789 return NULL; 2790 } 2791 nrt->rt_rmx = rt->rt_rmx; 2792 rtfree(rt); 2793 rt = nrt; 2794 } 2795 error = rt_timer_add(rt, icmp6_mtudisc_timeout, 2796 icmp6_mtudisc_timeout_q); 2797 if (error) { 2798 rtfree(rt); 2799 return NULL; 2800 } 2801 2802 return rt; /* caller need to call rtfree() */ 2803 } 2804 2805 static void 2806 icmp6_mtudisc_timeout(rt, r) 2807 struct rtentry *rt; 2808 struct rttimer *r; 2809 { 2810 if (rt == NULL) 2811 panic("icmp6_mtudisc_timeout: bad route to timeout"); 2812 if ((rt->rt_flags & (RTF_DYNAMIC | RTF_HOST)) == 2813 (RTF_DYNAMIC | RTF_HOST)) { 2814 rtrequest((int) RTM_DELETE, (struct sockaddr *)rt_key(rt), 2815 rt->rt_gateway, rt_mask(rt), rt->rt_flags, 0); 2816 } else { 2817 if (!(rt->rt_rmx.rmx_locks & RTV_MTU)) 2818 rt->rt_rmx.rmx_mtu = 0; 2819 } 2820 } 2821 2822 static void 2823 icmp6_redirect_timeout(rt, r) 2824 struct rtentry *rt; 2825 struct rttimer *r; 2826 { 2827 if (rt == NULL) 2828 panic("icmp6_redirect_timeout: bad route to timeout"); 2829 if ((rt->rt_flags & (RTF_GATEWAY | RTF_DYNAMIC | RTF_HOST)) == 2830 (RTF_GATEWAY | RTF_DYNAMIC | RTF_HOST)) { 2831 rtrequest((int) RTM_DELETE, (struct sockaddr *)rt_key(rt), 2832 rt->rt_gateway, rt_mask(rt), rt->rt_flags, 0); 2833 } 2834 } 2835 2836 /* 2837 * sysctl helper routine for the net.inet6.icmp6.nd6 nodes. silly? 2838 */ 2839 static int 2840 sysctl_net_inet6_icmp6_nd6(SYSCTLFN_ARGS) 2841 { 2842 2843 if (namelen != 0) 2844 return (EINVAL); 2845 2846 return (nd6_sysctl(rnode->sysctl_num, oldp, oldlenp, 2847 /*XXXUNCONST*/ 2848 __UNCONST(newp), newlen)); 2849 } 2850 2851 SYSCTL_SETUP(sysctl_net_inet6_icmp6_setup, 2852 "sysctl net.inet6.icmp6 subtree setup") 2853 { 2854 2855 sysctl_createv(clog, 0, NULL, NULL, 2856 CTLFLAG_PERMANENT, 2857 CTLTYPE_NODE, "net", NULL, 2858 NULL, 0, NULL, 0, 2859 CTL_NET, CTL_EOL); 2860 sysctl_createv(clog, 0, NULL, NULL, 2861 CTLFLAG_PERMANENT, 2862 CTLTYPE_NODE, "inet6", NULL, 2863 NULL, 0, NULL, 0, 2864 CTL_NET, PF_INET6, CTL_EOL); 2865 sysctl_createv(clog, 0, NULL, NULL, 2866 CTLFLAG_PERMANENT, 2867 CTLTYPE_NODE, "icmp6", 2868 SYSCTL_DESCR("ICMPv6 related settings"), 2869 NULL, 0, NULL, 0, 2870 CTL_NET, PF_INET6, IPPROTO_ICMPV6, CTL_EOL); 2871 2872 sysctl_createv(clog, 0, NULL, NULL, 2873 CTLFLAG_PERMANENT, 2874 CTLTYPE_STRUCT, "stats", 2875 SYSCTL_DESCR("ICMPv6 transmission statistics"), 2876 NULL, 0, &icmp6stat, sizeof(icmp6stat), 2877 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2878 ICMPV6CTL_STATS, CTL_EOL); 2879 sysctl_createv(clog, 0, NULL, NULL, 2880 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2881 CTLTYPE_INT, "rediraccept", 2882 SYSCTL_DESCR("Accept and process redirect messages"), 2883 NULL, 0, &icmp6_rediraccept, 0, 2884 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2885 ICMPV6CTL_REDIRACCEPT, CTL_EOL); 2886 sysctl_createv(clog, 0, NULL, NULL, 2887 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2888 CTLTYPE_INT, "redirtimeout", 2889 SYSCTL_DESCR("Redirect generated route lifetime"), 2890 NULL, 0, &icmp6_redirtimeout, 0, 2891 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2892 ICMPV6CTL_REDIRTIMEOUT, CTL_EOL); 2893 #if 0 /* obsoleted */ 2894 sysctl_createv(clog, 0, NULL, NULL, 2895 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2896 CTLTYPE_INT, "errratelimit", NULL, 2897 NULL, 0, &icmp6_errratelimit, 0, 2898 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2899 ICMPV6CTL_ERRRATELIMIT, CTL_EOL); 2900 #endif 2901 sysctl_createv(clog, 0, NULL, NULL, 2902 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2903 CTLTYPE_INT, "nd6_prune", 2904 SYSCTL_DESCR("Neighbor discovery prune interval"), 2905 NULL, 0, &nd6_prune, 0, 2906 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2907 ICMPV6CTL_ND6_PRUNE, CTL_EOL); 2908 sysctl_createv(clog, 0, NULL, NULL, 2909 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2910 CTLTYPE_INT, "nd6_delay", 2911 SYSCTL_DESCR("First probe delay time"), 2912 NULL, 0, &nd6_delay, 0, 2913 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2914 ICMPV6CTL_ND6_DELAY, CTL_EOL); 2915 sysctl_createv(clog, 0, NULL, NULL, 2916 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2917 CTLTYPE_INT, "nd6_umaxtries", 2918 SYSCTL_DESCR("Number of unicast discovery attempts"), 2919 NULL, 0, &nd6_umaxtries, 0, 2920 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2921 ICMPV6CTL_ND6_UMAXTRIES, CTL_EOL); 2922 sysctl_createv(clog, 0, NULL, NULL, 2923 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2924 CTLTYPE_INT, "nd6_mmaxtries", 2925 SYSCTL_DESCR("Number of multicast discovery attempts"), 2926 NULL, 0, &nd6_mmaxtries, 0, 2927 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2928 ICMPV6CTL_ND6_MMAXTRIES, CTL_EOL); 2929 sysctl_createv(clog, 0, NULL, NULL, 2930 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2931 CTLTYPE_INT, "nd6_useloopback", 2932 SYSCTL_DESCR("Use loopback interface for local traffic"), 2933 NULL, 0, &nd6_useloopback, 0, 2934 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2935 ICMPV6CTL_ND6_USELOOPBACK, CTL_EOL); 2936 #if 0 /* obsoleted */ 2937 sysctl_createv(clog, 0, NULL, NULL, 2938 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2939 CTLTYPE_INT, "nd6_proxyall", NULL, 2940 NULL, 0, &nd6_proxyall, 0, 2941 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2942 ICMPV6CTL_ND6_PROXYALL, CTL_EOL); 2943 #endif 2944 sysctl_createv(clog, 0, NULL, NULL, 2945 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2946 CTLTYPE_INT, "nodeinfo", 2947 SYSCTL_DESCR("Respond to node information requests"), 2948 NULL, 0, &icmp6_nodeinfo, 0, 2949 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2950 ICMPV6CTL_NODEINFO, CTL_EOL); 2951 sysctl_createv(clog, 0, NULL, NULL, 2952 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2953 CTLTYPE_INT, "errppslimit", 2954 SYSCTL_DESCR("Maximum ICMP errors sent per second"), 2955 NULL, 0, &icmp6errppslim, 0, 2956 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2957 ICMPV6CTL_ERRPPSLIMIT, CTL_EOL); 2958 sysctl_createv(clog, 0, NULL, NULL, 2959 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2960 CTLTYPE_INT, "nd6_maxnudhint", 2961 SYSCTL_DESCR("Maximum neighbor unreachable hint count"), 2962 NULL, 0, &nd6_maxnudhint, 0, 2963 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2964 ICMPV6CTL_ND6_MAXNUDHINT, CTL_EOL); 2965 sysctl_createv(clog, 0, NULL, NULL, 2966 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2967 CTLTYPE_INT, "mtudisc_hiwat", 2968 SYSCTL_DESCR("Low mark on MTU Discovery route timers"), 2969 NULL, 0, &icmp6_mtudisc_hiwat, 0, 2970 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2971 ICMPV6CTL_MTUDISC_HIWAT, CTL_EOL); 2972 sysctl_createv(clog, 0, NULL, NULL, 2973 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2974 CTLTYPE_INT, "mtudisc_lowat", 2975 SYSCTL_DESCR("Low mark on MTU Discovery route timers"), 2976 NULL, 0, &icmp6_mtudisc_lowat, 0, 2977 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2978 ICMPV6CTL_MTUDISC_LOWAT, CTL_EOL); 2979 sysctl_createv(clog, 0, NULL, NULL, 2980 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2981 CTLTYPE_INT, "nd6_debug", 2982 SYSCTL_DESCR("Enable neighbor discovery debug output"), 2983 NULL, 0, &nd6_debug, 0, 2984 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2985 ICMPV6CTL_ND6_DEBUG, CTL_EOL); 2986 sysctl_createv(clog, 0, NULL, NULL, 2987 CTLFLAG_PERMANENT, 2988 CTLTYPE_STRUCT, "nd6_drlist", 2989 SYSCTL_DESCR("Default router list"), 2990 sysctl_net_inet6_icmp6_nd6, 0, NULL, 0, 2991 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2992 ICMPV6CTL_ND6_DRLIST, CTL_EOL); 2993 sysctl_createv(clog, 0, NULL, NULL, 2994 CTLFLAG_PERMANENT, 2995 CTLTYPE_STRUCT, "nd6_prlist", 2996 SYSCTL_DESCR("Prefix list"), 2997 sysctl_net_inet6_icmp6_nd6, 0, NULL, 0, 2998 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2999 ICMPV6CTL_ND6_PRLIST, CTL_EOL); 3000 } 3001
Indexes created Thu Oct 16 14:10:15 GMT 2025