icmp6.c revision 1.113
1 /* $NetBSD: icmp6.c,v 1.113 2006/01/21 00:15:36 rpaulo 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 2006/01/21 00:15:36 rpaulo 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.tv_sec) 1858 ltime = ifa6->ia6_lifetime.ia6t_expire - time.tv_sec; 1859 else 1860 ltime = 0; 1861 } 1862 if (ltime > 0x7fffffff) 1863 ltime = 0x7fffffff; 1864 ltime = htonl(ltime); 1865 1866 bcopy(<ime, cp, sizeof(u_int32_t)); 1867 cp += sizeof(u_int32_t); 1868 1869 /* copy the address itself */ 1870 bcopy(&ifa6->ia_addr.sin6_addr, cp, 1871 sizeof(struct in6_addr)); 1872 in6_clearscope((struct in6_addr *)cp); /* XXX */ 1873 cp += sizeof(struct in6_addr); 1874 1875 resid -= (sizeof(struct in6_addr) + sizeof(u_int32_t)); 1876 copied += (sizeof(struct in6_addr) + 1877 sizeof(u_int32_t)); 1878 } 1879 if (ifp0) /* we need search only on the specified IF */ 1880 break; 1881 } 1882 1883 if (allow_deprecated == 0 && ifp_dep != NULL) { 1884 ifp = ifp_dep; 1885 allow_deprecated = 1; 1886 1887 goto again; 1888 } 1889 1890 return (copied); 1891 } 1892 1893 /* 1894 * XXX almost dup'ed code with rip6_input. 1895 */ 1896 static int 1897 icmp6_rip6_input(mp, off) 1898 struct mbuf **mp; 1899 int off; 1900 { 1901 struct mbuf *m = *mp; 1902 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1903 struct inpcb_hdr *inph; 1904 struct in6pcb *in6p; 1905 struct in6pcb *last = NULL; 1906 struct sockaddr_in6 rip6src; 1907 struct icmp6_hdr *icmp6; 1908 struct mbuf *opts = NULL; 1909 1910 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 1911 if (icmp6 == NULL) { 1912 /* m is already reclaimed */ 1913 return IPPROTO_DONE; 1914 } 1915 1916 /* 1917 * XXX: the address may have embedded scope zone ID, which should be 1918 * hidden from applications. 1919 */ 1920 bzero(&rip6src, sizeof(rip6src)); 1921 rip6src.sin6_len = sizeof(struct sockaddr_in6); 1922 rip6src.sin6_family = AF_INET6; 1923 rip6src.sin6_addr = ip6->ip6_src; 1924 if (sa6_recoverscope(&rip6src)) { 1925 m_freem(m); 1926 return (IPPROTO_DONE); 1927 } 1928 1929 CIRCLEQ_FOREACH(inph, &raw6cbtable.inpt_queue, inph_queue) { 1930 in6p = (struct in6pcb *)inph; 1931 if (in6p->in6p_af != AF_INET6) 1932 continue; 1933 if (in6p->in6p_ip6.ip6_nxt != IPPROTO_ICMPV6) 1934 continue; 1935 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr) && 1936 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr, &ip6->ip6_dst)) 1937 continue; 1938 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr) && 1939 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr, &ip6->ip6_src)) 1940 continue; 1941 if (in6p->in6p_icmp6filt 1942 && ICMP6_FILTER_WILLBLOCK(icmp6->icmp6_type, 1943 in6p->in6p_icmp6filt)) 1944 continue; 1945 if (last) { 1946 struct mbuf *n; 1947 if ((n = m_copy(m, 0, (int)M_COPYALL)) != NULL) { 1948 if (last->in6p_flags & IN6P_CONTROLOPTS) 1949 ip6_savecontrol(last, &opts, ip6, n); 1950 /* strip intermediate headers */ 1951 m_adj(n, off); 1952 if (sbappendaddr(&last->in6p_socket->so_rcv, 1953 (struct sockaddr *)&rip6src, 1954 n, opts) == 0) { 1955 /* should notify about lost packet */ 1956 m_freem(n); 1957 if (opts) 1958 m_freem(opts); 1959 } else 1960 sorwakeup(last->in6p_socket); 1961 opts = NULL; 1962 } 1963 } 1964 last = in6p; 1965 } 1966 if (last) { 1967 if (last->in6p_flags & IN6P_CONTROLOPTS) 1968 ip6_savecontrol(last, &opts, ip6, m); 1969 /* strip intermediate headers */ 1970 m_adj(m, off); 1971 if (sbappendaddr(&last->in6p_socket->so_rcv, 1972 (struct sockaddr *)&rip6src, m, opts) == 0) { 1973 m_freem(m); 1974 if (opts) 1975 m_freem(opts); 1976 } else 1977 sorwakeup(last->in6p_socket); 1978 } else { 1979 m_freem(m); 1980 ip6stat.ip6s_delivered--; 1981 } 1982 return IPPROTO_DONE; 1983 } 1984 1985 /* 1986 * Reflect the ip6 packet back to the source. 1987 * OFF points to the icmp6 header, counted from the top of the mbuf. 1988 * 1989 * Note: RFC 1885 required that an echo reply should be truncated if it 1990 * did not fit in with (return) path MTU, and KAME code supported the 1991 * behavior. However, as a clarification after the RFC, this limitation 1992 * was removed in a revised version of the spec, RFC 2463. We had kept the 1993 * old behavior, with a (non-default) ifdef block, while the new version of 1994 * the spec was an internet-draft status, and even after the new RFC was 1995 * published. But it would rather make sense to clean the obsoleted part 1996 * up, and to make the code simpler at this stage. 1997 */ 1998 void 1999 icmp6_reflect(m, off) 2000 struct mbuf *m; 2001 size_t off; 2002 { 2003 struct ip6_hdr *ip6; 2004 struct icmp6_hdr *icmp6; 2005 struct in6_ifaddr *ia; 2006 int plen; 2007 int type, code; 2008 struct ifnet *outif = NULL; 2009 struct in6_addr origdst, *src = NULL; 2010 2011 /* too short to reflect */ 2012 if (off < sizeof(struct ip6_hdr)) { 2013 nd6log((LOG_DEBUG, 2014 "sanity fail: off=%lx, sizeof(ip6)=%lx in %s:%d\n", 2015 (u_long)off, (u_long)sizeof(struct ip6_hdr), 2016 __FILE__, __LINE__)); 2017 goto bad; 2018 } 2019 2020 /* 2021 * If there are extra headers between IPv6 and ICMPv6, strip 2022 * off that header first. 2023 */ 2024 #ifdef DIAGNOSTIC 2025 if (sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) > MHLEN) 2026 panic("assumption failed in icmp6_reflect"); 2027 #endif 2028 if (off > sizeof(struct ip6_hdr)) { 2029 size_t l; 2030 struct ip6_hdr nip6; 2031 2032 l = off - sizeof(struct ip6_hdr); 2033 m_copydata(m, 0, sizeof(nip6), (caddr_t)&nip6); 2034 m_adj(m, l); 2035 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 2036 if (m->m_len < l) { 2037 if ((m = m_pullup(m, l)) == NULL) 2038 return; 2039 } 2040 bcopy((caddr_t)&nip6, mtod(m, caddr_t), sizeof(nip6)); 2041 } else /* off == sizeof(struct ip6_hdr) */ { 2042 size_t l; 2043 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 2044 if (m->m_len < l) { 2045 if ((m = m_pullup(m, l)) == NULL) 2046 return; 2047 } 2048 } 2049 plen = m->m_pkthdr.len - sizeof(struct ip6_hdr); 2050 ip6 = mtod(m, struct ip6_hdr *); 2051 ip6->ip6_nxt = IPPROTO_ICMPV6; 2052 icmp6 = (struct icmp6_hdr *)(ip6 + 1); 2053 type = icmp6->icmp6_type; /* keep type for statistics */ 2054 code = icmp6->icmp6_code; /* ditto. */ 2055 2056 origdst = ip6->ip6_dst; 2057 /* 2058 * ip6_input() drops a packet if its src is multicast. 2059 * So, the src is never multicast. 2060 */ 2061 ip6->ip6_dst = ip6->ip6_src; 2062 2063 /* 2064 * If the incoming packet was addressed directly to us (i.e. unicast), 2065 * use dst as the src for the reply. 2066 * The IN6_IFF_NOTREADY case would be VERY rare, but is possible 2067 * (for example) when we encounter an error while forwarding procedure 2068 * destined to a duplicated address of ours. 2069 * Note that ip6_getdstifaddr() may fail if we are in an error handling 2070 * procedure of an outgoing packet of our own, in which case we need 2071 * to search in the ifaddr list. 2072 */ 2073 if (!IN6_IS_ADDR_MULTICAST(&origdst)) { 2074 if ((ia = ip6_getdstifaddr(m))) { 2075 if (!(ia->ia6_flags & 2076 (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY))) 2077 src = &ia->ia_addr.sin6_addr; 2078 } else { 2079 struct sockaddr_in6 d; 2080 2081 bzero(&d, sizeof(d)); 2082 d.sin6_family = AF_INET6; 2083 d.sin6_len = sizeof(d); 2084 d.sin6_addr = origdst; 2085 ia = (struct in6_ifaddr *) 2086 ifa_ifwithaddr((struct sockaddr *)&d); 2087 if (ia && 2088 !(ia->ia6_flags & 2089 (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY))) { 2090 src = &ia->ia_addr.sin6_addr; 2091 } 2092 } 2093 } 2094 2095 if (src == NULL) { 2096 int e; 2097 struct sockaddr_in6 sin6; 2098 struct route_in6 ro; 2099 2100 /* 2101 * This case matches to multicasts, our anycast, or unicasts 2102 * that we do not own. Select a source address based on the 2103 * source address of the erroneous packet. 2104 */ 2105 bzero(&sin6, sizeof(sin6)); 2106 sin6.sin6_family = AF_INET6; 2107 sin6.sin6_len = sizeof(sin6); 2108 sin6.sin6_addr = ip6->ip6_dst; /* zone ID should be embedded */ 2109 2110 bzero(&ro, sizeof(ro)); 2111 src = in6_selectsrc(&sin6, NULL, NULL, &ro, NULL, &outif, &e); 2112 if (ro.ro_rt) { /* XXX: see comments in icmp6_mtudisc_update */ 2113 RTFREE(ro.ro_rt); /* XXX: we could use this */ 2114 } 2115 if (src == NULL) { 2116 nd6log((LOG_DEBUG, 2117 "icmp6_reflect: source can't be determined: " 2118 "dst=%s, error=%d\n", 2119 ip6_sprintf(&sin6.sin6_addr), e)); 2120 goto bad; 2121 } 2122 } 2123 2124 ip6->ip6_src = *src; 2125 ip6->ip6_flow = 0; 2126 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2127 ip6->ip6_vfc |= IPV6_VERSION; 2128 ip6->ip6_nxt = IPPROTO_ICMPV6; 2129 if (m->m_pkthdr.rcvif) { 2130 /* XXX: This may not be the outgoing interface */ 2131 ip6->ip6_hlim = ND_IFINFO(m->m_pkthdr.rcvif)->chlim; 2132 } else 2133 ip6->ip6_hlim = ip6_defhlim; 2134 2135 icmp6->icmp6_cksum = 0; 2136 icmp6->icmp6_cksum = in6_cksum(m, IPPROTO_ICMPV6, 2137 sizeof(struct ip6_hdr), plen); 2138 2139 /* 2140 * XXX option handling 2141 */ 2142 2143 m->m_flags &= ~(M_BCAST|M_MCAST); 2144 2145 /* 2146 * To avoid a "too big" situation at an intermediate router 2147 * and the path MTU discovery process, specify the IPV6_MINMTU flag. 2148 * Note that only echo and node information replies are affected, 2149 * since the length of ICMP6 errors is limited to the minimum MTU. 2150 */ 2151 if (ip6_output(m, NULL, NULL, IPV6_MINMTU, 2152 (struct ip6_moptions *)NULL, (struct socket *)NULL, &outif) != 0 2153 && outif) 2154 icmp6_ifstat_inc(outif, ifs6_out_error); 2155 2156 if (outif) 2157 icmp6_ifoutstat_inc(outif, type, code); 2158 2159 return; 2160 2161 bad: 2162 m_freem(m); 2163 return; 2164 } 2165 2166 void 2167 icmp6_fasttimo() 2168 { 2169 2170 mld6_fasttimeo(); 2171 } 2172 2173 static const char * 2174 icmp6_redirect_diag(src6, dst6, tgt6) 2175 struct in6_addr *src6; 2176 struct in6_addr *dst6; 2177 struct in6_addr *tgt6; 2178 { 2179 static char buf[1024]; 2180 snprintf(buf, sizeof(buf), "(src=%s dst=%s tgt=%s)", 2181 ip6_sprintf(src6), ip6_sprintf(dst6), ip6_sprintf(tgt6)); 2182 return buf; 2183 } 2184 2185 void 2186 icmp6_redirect_input(m, off) 2187 struct mbuf *m; 2188 int off; 2189 { 2190 struct ifnet *ifp = m->m_pkthdr.rcvif; 2191 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 2192 struct nd_redirect *nd_rd; 2193 int icmp6len = ntohs(ip6->ip6_plen); 2194 char *lladdr = NULL; 2195 int lladdrlen = 0; 2196 struct rtentry *rt = NULL; 2197 int is_router; 2198 int is_onlink; 2199 struct in6_addr src6 = ip6->ip6_src; 2200 struct in6_addr redtgt6; 2201 struct in6_addr reddst6; 2202 union nd_opts ndopts; 2203 2204 if (!ifp) 2205 return; 2206 2207 /* XXX if we are router, we don't update route by icmp6 redirect */ 2208 if (ip6_forwarding) 2209 goto freeit; 2210 if (!icmp6_rediraccept) 2211 goto freeit; 2212 2213 IP6_EXTHDR_GET(nd_rd, struct nd_redirect *, m, off, icmp6len); 2214 if (nd_rd == NULL) { 2215 icmp6stat.icp6s_tooshort++; 2216 return; 2217 } 2218 redtgt6 = nd_rd->nd_rd_target; 2219 reddst6 = nd_rd->nd_rd_dst; 2220 2221 if (in6_setscope(&redtgt6, m->m_pkthdr.rcvif, NULL) || 2222 in6_setscope(&reddst6, m->m_pkthdr.rcvif, NULL)) { 2223 goto freeit; 2224 } 2225 2226 /* validation */ 2227 if (!IN6_IS_ADDR_LINKLOCAL(&src6)) { 2228 nd6log((LOG_ERR, 2229 "ICMP6 redirect sent from %s rejected; " 2230 "must be from linklocal\n", ip6_sprintf(&src6))); 2231 goto bad; 2232 } 2233 if (ip6->ip6_hlim != 255) { 2234 nd6log((LOG_ERR, 2235 "ICMP6 redirect sent from %s rejected; " 2236 "hlim=%d (must be 255)\n", 2237 ip6_sprintf(&src6), ip6->ip6_hlim)); 2238 goto bad; 2239 } 2240 { 2241 /* ip6->ip6_src must be equal to gw for icmp6->icmp6_reddst */ 2242 struct sockaddr_in6 sin6; 2243 struct in6_addr *gw6; 2244 2245 bzero(&sin6, sizeof(sin6)); 2246 sin6.sin6_family = AF_INET6; 2247 sin6.sin6_len = sizeof(struct sockaddr_in6); 2248 bcopy(&reddst6, &sin6.sin6_addr, sizeof(reddst6)); 2249 rt = rtalloc1((struct sockaddr *)&sin6, 0); 2250 if (rt) { 2251 if (rt->rt_gateway == NULL || 2252 rt->rt_gateway->sa_family != AF_INET6) { 2253 nd6log((LOG_ERR, 2254 "ICMP6 redirect rejected; no route " 2255 "with inet6 gateway found for redirect dst: %s\n", 2256 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2257 RTFREE(rt); 2258 goto bad; 2259 } 2260 2261 gw6 = &(((struct sockaddr_in6 *)rt->rt_gateway)->sin6_addr); 2262 if (bcmp(&src6, gw6, sizeof(struct in6_addr)) != 0) { 2263 nd6log((LOG_ERR, 2264 "ICMP6 redirect rejected; " 2265 "not equal to gw-for-src=%s (must be same): " 2266 "%s\n", 2267 ip6_sprintf(gw6), 2268 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2269 RTFREE(rt); 2270 goto bad; 2271 } 2272 } else { 2273 nd6log((LOG_ERR, 2274 "ICMP6 redirect rejected; " 2275 "no route found for redirect dst: %s\n", 2276 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2277 goto bad; 2278 } 2279 RTFREE(rt); 2280 rt = NULL; 2281 } 2282 if (IN6_IS_ADDR_MULTICAST(&reddst6)) { 2283 nd6log((LOG_ERR, 2284 "ICMP6 redirect rejected; " 2285 "redirect dst must be unicast: %s\n", 2286 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2287 goto bad; 2288 } 2289 2290 is_router = is_onlink = 0; 2291 if (IN6_IS_ADDR_LINKLOCAL(&redtgt6)) 2292 is_router = 1; /* router case */ 2293 if (bcmp(&redtgt6, &reddst6, sizeof(redtgt6)) == 0) 2294 is_onlink = 1; /* on-link destination case */ 2295 if (!is_router && !is_onlink) { 2296 nd6log((LOG_ERR, 2297 "ICMP6 redirect rejected; " 2298 "neither router case nor onlink case: %s\n", 2299 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2300 goto bad; 2301 } 2302 /* validation passed */ 2303 2304 icmp6len -= sizeof(*nd_rd); 2305 nd6_option_init(nd_rd + 1, icmp6len, &ndopts); 2306 if (nd6_options(&ndopts) < 0) { 2307 nd6log((LOG_INFO, "icmp6_redirect_input: " 2308 "invalid ND option, rejected: %s\n", 2309 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2310 /* nd6_options have incremented stats */ 2311 goto freeit; 2312 } 2313 2314 if (ndopts.nd_opts_tgt_lladdr) { 2315 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 2316 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 2317 } 2318 2319 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 2320 nd6log((LOG_INFO, 2321 "icmp6_redirect_input: lladdrlen mismatch for %s " 2322 "(if %d, icmp6 packet %d): %s\n", 2323 ip6_sprintf(&redtgt6), ifp->if_addrlen, lladdrlen - 2, 2324 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2325 goto bad; 2326 } 2327 2328 /* RFC 2461 8.3 */ 2329 nd6_cache_lladdr(ifp, &redtgt6, lladdr, lladdrlen, ND_REDIRECT, 2330 is_onlink ? ND_REDIRECT_ONLINK : ND_REDIRECT_ROUTER); 2331 2332 if (!is_onlink) { /* better router case. perform rtredirect. */ 2333 /* perform rtredirect */ 2334 struct sockaddr_in6 sdst; 2335 struct sockaddr_in6 sgw; 2336 struct sockaddr_in6 ssrc; 2337 unsigned long rtcount; 2338 struct rtentry *newrt = NULL; 2339 2340 /* 2341 * do not install redirect route, if the number of entries 2342 * is too much (> hiwat). note that, the node (= host) will 2343 * work just fine even if we do not install redirect route 2344 * (there will be additional hops, though). 2345 */ 2346 rtcount = rt_timer_count(icmp6_redirect_timeout_q); 2347 if (0 <= icmp6_redirect_hiwat && rtcount > icmp6_redirect_hiwat) 2348 return; 2349 else if (0 <= icmp6_redirect_lowat && 2350 rtcount > icmp6_redirect_lowat) { 2351 /* 2352 * XXX nuke a victim, install the new one. 2353 */ 2354 } 2355 2356 bzero(&sdst, sizeof(sdst)); 2357 bzero(&sgw, sizeof(sgw)); 2358 bzero(&ssrc, sizeof(ssrc)); 2359 sdst.sin6_family = sgw.sin6_family = ssrc.sin6_family = AF_INET6; 2360 sdst.sin6_len = sgw.sin6_len = ssrc.sin6_len = 2361 sizeof(struct sockaddr_in6); 2362 bcopy(&redtgt6, &sgw.sin6_addr, sizeof(struct in6_addr)); 2363 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2364 bcopy(&src6, &ssrc.sin6_addr, sizeof(struct in6_addr)); 2365 rtredirect((struct sockaddr *)&sdst, (struct sockaddr *)&sgw, 2366 (struct sockaddr *)NULL, RTF_GATEWAY | RTF_HOST, 2367 (struct sockaddr *)&ssrc, 2368 &newrt); 2369 2370 if (newrt) { 2371 (void)rt_timer_add(newrt, icmp6_redirect_timeout, 2372 icmp6_redirect_timeout_q); 2373 rtfree(newrt); 2374 } 2375 } 2376 /* finally update cached route in each socket via pfctlinput */ 2377 { 2378 struct sockaddr_in6 sdst; 2379 2380 bzero(&sdst, sizeof(sdst)); 2381 sdst.sin6_family = AF_INET6; 2382 sdst.sin6_len = sizeof(struct sockaddr_in6); 2383 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2384 pfctlinput(PRC_REDIRECT_HOST, (struct sockaddr *)&sdst); 2385 #ifdef IPSEC 2386 key_sa_routechange((struct sockaddr *)&sdst); 2387 #endif 2388 } 2389 2390 freeit: 2391 m_freem(m); 2392 return; 2393 2394 bad: 2395 icmp6stat.icp6s_badredirect++; 2396 m_freem(m); 2397 } 2398 2399 void 2400 icmp6_redirect_output(m0, rt) 2401 struct mbuf *m0; 2402 struct rtentry *rt; 2403 { 2404 struct ifnet *ifp; /* my outgoing interface */ 2405 struct in6_addr *ifp_ll6; 2406 struct in6_addr *nexthop; 2407 struct ip6_hdr *sip6; /* m0 as struct ip6_hdr */ 2408 struct mbuf *m = NULL; /* newly allocated one */ 2409 struct ip6_hdr *ip6; /* m as struct ip6_hdr */ 2410 struct nd_redirect *nd_rd; 2411 size_t maxlen; 2412 u_char *p; 2413 struct sockaddr_in6 src_sa; 2414 2415 icmp6_errcount(&icmp6stat.icp6s_outerrhist, ND_REDIRECT, 0); 2416 2417 /* if we are not router, we don't send icmp6 redirect */ 2418 if (!ip6_forwarding) 2419 goto fail; 2420 2421 /* sanity check */ 2422 if (!m0 || !rt || !(rt->rt_flags & RTF_UP) || !(ifp = rt->rt_ifp)) 2423 goto fail; 2424 2425 /* 2426 * Address check: 2427 * the source address must identify a neighbor, and 2428 * the destination address must not be a multicast address 2429 * [RFC 2461, sec 8.2] 2430 */ 2431 sip6 = mtod(m0, struct ip6_hdr *); 2432 bzero(&src_sa, sizeof(src_sa)); 2433 src_sa.sin6_family = AF_INET6; 2434 src_sa.sin6_len = sizeof(src_sa); 2435 src_sa.sin6_addr = sip6->ip6_src; 2436 if (nd6_is_addr_neighbor(&src_sa, ifp) == 0) 2437 goto fail; 2438 if (IN6_IS_ADDR_MULTICAST(&sip6->ip6_dst)) 2439 goto fail; /* what should we do here? */ 2440 2441 /* rate limit */ 2442 if (icmp6_ratelimit(&sip6->ip6_src, ND_REDIRECT, 0)) 2443 goto fail; 2444 2445 /* 2446 * Since we are going to append up to 1280 bytes (= IPV6_MMTU), 2447 * we almost always ask for an mbuf cluster for simplicity. 2448 * (MHLEN < IPV6_MMTU is almost always true) 2449 */ 2450 #if IPV6_MMTU >= MCLBYTES 2451 # error assumption failed about IPV6_MMTU and MCLBYTES 2452 #endif 2453 MGETHDR(m, M_DONTWAIT, MT_HEADER); 2454 if (m && IPV6_MMTU >= MHLEN) 2455 MCLGET(m, M_DONTWAIT); 2456 if (!m) 2457 goto fail; 2458 m->m_pkthdr.rcvif = NULL; 2459 m->m_len = 0; 2460 maxlen = M_TRAILINGSPACE(m); 2461 maxlen = min(IPV6_MMTU, maxlen); 2462 /* just for safety */ 2463 if (maxlen < sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) + 2464 ((sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7)) { 2465 goto fail; 2466 } 2467 2468 { 2469 /* get ip6 linklocal address for ifp(my outgoing interface). */ 2470 struct in6_ifaddr *ia; 2471 if ((ia = in6ifa_ifpforlinklocal(ifp, 2472 IN6_IFF_NOTREADY| 2473 IN6_IFF_ANYCAST)) == NULL) 2474 goto fail; 2475 ifp_ll6 = &ia->ia_addr.sin6_addr; 2476 } 2477 2478 /* get ip6 linklocal address for the router. */ 2479 if (rt->rt_gateway && (rt->rt_flags & RTF_GATEWAY)) { 2480 struct sockaddr_in6 *sin6; 2481 sin6 = (struct sockaddr_in6 *)rt->rt_gateway; 2482 nexthop = &sin6->sin6_addr; 2483 if (!IN6_IS_ADDR_LINKLOCAL(nexthop)) 2484 nexthop = NULL; 2485 } else 2486 nexthop = NULL; 2487 2488 /* ip6 */ 2489 ip6 = mtod(m, struct ip6_hdr *); 2490 ip6->ip6_flow = 0; 2491 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2492 ip6->ip6_vfc |= IPV6_VERSION; 2493 /* ip6->ip6_plen will be set later */ 2494 ip6->ip6_nxt = IPPROTO_ICMPV6; 2495 ip6->ip6_hlim = 255; 2496 /* ip6->ip6_src must be linklocal addr for my outgoing if. */ 2497 bcopy(ifp_ll6, &ip6->ip6_src, sizeof(struct in6_addr)); 2498 bcopy(&sip6->ip6_src, &ip6->ip6_dst, sizeof(struct in6_addr)); 2499 2500 /* ND Redirect */ 2501 nd_rd = (struct nd_redirect *)(ip6 + 1); 2502 nd_rd->nd_rd_type = ND_REDIRECT; 2503 nd_rd->nd_rd_code = 0; 2504 nd_rd->nd_rd_reserved = 0; 2505 if (rt->rt_flags & RTF_GATEWAY) { 2506 /* 2507 * nd_rd->nd_rd_target must be a link-local address in 2508 * better router cases. 2509 */ 2510 if (!nexthop) 2511 goto fail; 2512 bcopy(nexthop, &nd_rd->nd_rd_target, 2513 sizeof(nd_rd->nd_rd_target)); 2514 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2515 sizeof(nd_rd->nd_rd_dst)); 2516 } else { 2517 /* make sure redtgt == reddst */ 2518 nexthop = &sip6->ip6_dst; 2519 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_target, 2520 sizeof(nd_rd->nd_rd_target)); 2521 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2522 sizeof(nd_rd->nd_rd_dst)); 2523 } 2524 2525 p = (u_char *)(nd_rd + 1); 2526 2527 { 2528 /* target lladdr option */ 2529 struct rtentry *rt_nexthop = NULL; 2530 int len; 2531 struct sockaddr_dl *sdl; 2532 struct nd_opt_hdr *nd_opt; 2533 char *lladdr; 2534 2535 rt_nexthop = nd6_lookup(nexthop, 0, ifp); 2536 if (!rt_nexthop) 2537 goto nolladdropt; 2538 len = sizeof(*nd_opt) + ifp->if_addrlen; 2539 len = (len + 7) & ~7; /* round by 8 */ 2540 /* safety check */ 2541 if (len + (p - (u_char *)ip6) > maxlen) 2542 goto nolladdropt; 2543 if (!(rt_nexthop->rt_flags & RTF_GATEWAY) && 2544 (rt_nexthop->rt_flags & RTF_LLINFO) && 2545 (rt_nexthop->rt_gateway->sa_family == AF_LINK) && 2546 (sdl = (struct sockaddr_dl *)rt_nexthop->rt_gateway) && 2547 sdl->sdl_alen) { 2548 nd_opt = (struct nd_opt_hdr *)p; 2549 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 2550 nd_opt->nd_opt_len = len >> 3; 2551 lladdr = (char *)(nd_opt + 1); 2552 bcopy(LLADDR(sdl), lladdr, ifp->if_addrlen); 2553 p += len; 2554 } 2555 } 2556 nolladdropt:; 2557 2558 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2559 2560 /* just to be safe */ 2561 if (m0->m_flags & M_DECRYPTED) 2562 goto noredhdropt; 2563 if (p - (u_char *)ip6 > maxlen) 2564 goto noredhdropt; 2565 2566 { 2567 /* redirected header option */ 2568 int len; 2569 struct nd_opt_rd_hdr *nd_opt_rh; 2570 2571 /* 2572 * compute the maximum size for icmp6 redirect header option. 2573 * XXX room for auth header? 2574 */ 2575 len = maxlen - (p - (u_char *)ip6); 2576 len &= ~7; 2577 2578 /* 2579 * Redirected header option spec (RFC2461 4.6.3) talks nothing 2580 * about padding/truncate rule for the original IP packet. 2581 * From the discussion on IPv6imp in Feb 1999, 2582 * the consensus was: 2583 * - "attach as much as possible" is the goal 2584 * - pad if not aligned (original size can be guessed by 2585 * original ip6 header) 2586 * Following code adds the padding if it is simple enough, 2587 * and truncates if not. 2588 */ 2589 if (len - sizeof(*nd_opt_rh) < m0->m_pkthdr.len) { 2590 /* not enough room, truncate */ 2591 m_adj(m0, (len - sizeof(*nd_opt_rh)) - 2592 m0->m_pkthdr.len); 2593 } else { 2594 /* 2595 * enough room, truncate if not aligned. 2596 * we don't pad here for simplicity. 2597 */ 2598 size_t extra; 2599 2600 extra = m0->m_pkthdr.len % 8; 2601 if (extra) { 2602 /* truncate */ 2603 m_adj(m0, -extra); 2604 } 2605 len = m0->m_pkthdr.len + sizeof(*nd_opt_rh); 2606 } 2607 2608 nd_opt_rh = (struct nd_opt_rd_hdr *)p; 2609 bzero(nd_opt_rh, sizeof(*nd_opt_rh)); 2610 nd_opt_rh->nd_opt_rh_type = ND_OPT_REDIRECTED_HEADER; 2611 nd_opt_rh->nd_opt_rh_len = len >> 3; 2612 p += sizeof(*nd_opt_rh); 2613 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2614 2615 /* connect m0 to m */ 2616 m->m_pkthdr.len += m0->m_pkthdr.len; 2617 m_cat(m, m0); 2618 m0 = NULL; 2619 } 2620 noredhdropt: 2621 if (m0) { 2622 m_freem(m0); 2623 m0 = NULL; 2624 } 2625 2626 sip6 = mtod(m, struct ip6_hdr *); 2627 /* XXX: clear embedded link IDs in the inner header */ 2628 in6_clearscope(&sip6->ip6_src); 2629 in6_clearscope(&sip6->ip6_dst); 2630 in6_clearscope(&nd_rd->nd_rd_target); 2631 in6_clearscope(&nd_rd->nd_rd_dst); 2632 2633 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr)); 2634 2635 nd_rd->nd_rd_cksum = 0; 2636 nd_rd->nd_rd_cksum 2637 = in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), ntohs(ip6->ip6_plen)); 2638 2639 /* send the packet to outside... */ 2640 if (ip6_output(m, NULL, NULL, 0, 2641 (struct ip6_moptions *)NULL, (struct socket *)NULL, NULL) != 0) 2642 icmp6_ifstat_inc(ifp, ifs6_out_error); 2643 2644 icmp6_ifstat_inc(ifp, ifs6_out_msg); 2645 icmp6_ifstat_inc(ifp, ifs6_out_redirect); 2646 icmp6stat.icp6s_outhist[ND_REDIRECT]++; 2647 2648 return; 2649 2650 fail: 2651 if (m) 2652 m_freem(m); 2653 if (m0) 2654 m_freem(m0); 2655 } 2656 2657 /* 2658 * ICMPv6 socket option processing. 2659 */ 2660 int 2661 icmp6_ctloutput(op, so, level, optname, mp) 2662 int op; 2663 struct socket *so; 2664 int level, optname; 2665 struct mbuf **mp; 2666 { 2667 int error = 0; 2668 int optlen; 2669 struct in6pcb *in6p = sotoin6pcb(so); 2670 struct mbuf *m = *mp; 2671 2672 optlen = m ? m->m_len : 0; 2673 2674 if (level != IPPROTO_ICMPV6) { 2675 if (op == PRCO_SETOPT && m) 2676 (void)m_free(m); 2677 return EINVAL; 2678 } 2679 2680 switch (op) { 2681 case PRCO_SETOPT: 2682 switch (optname) { 2683 case ICMP6_FILTER: 2684 { 2685 struct icmp6_filter *p; 2686 2687 if (optlen != sizeof(*p)) { 2688 error = EMSGSIZE; 2689 break; 2690 } 2691 p = mtod(m, struct icmp6_filter *); 2692 if (!p || !in6p->in6p_icmp6filt) { 2693 error = EINVAL; 2694 break; 2695 } 2696 bcopy(p, in6p->in6p_icmp6filt, 2697 sizeof(struct icmp6_filter)); 2698 error = 0; 2699 break; 2700 } 2701 2702 default: 2703 error = ENOPROTOOPT; 2704 break; 2705 } 2706 if (m) 2707 (void)m_freem(m); 2708 break; 2709 2710 case PRCO_GETOPT: 2711 switch (optname) { 2712 case ICMP6_FILTER: 2713 { 2714 struct icmp6_filter *p; 2715 2716 if (!in6p->in6p_icmp6filt) { 2717 error = EINVAL; 2718 break; 2719 } 2720 *mp = m = m_get(M_WAIT, MT_SOOPTS); 2721 m->m_len = sizeof(struct icmp6_filter); 2722 p = mtod(m, struct icmp6_filter *); 2723 bcopy(in6p->in6p_icmp6filt, p, 2724 sizeof(struct icmp6_filter)); 2725 error = 0; 2726 break; 2727 } 2728 2729 default: 2730 error = ENOPROTOOPT; 2731 break; 2732 } 2733 break; 2734 } 2735 2736 return (error); 2737 } 2738 2739 /* 2740 * Perform rate limit check. 2741 * Returns 0 if it is okay to send the icmp6 packet. 2742 * Returns 1 if the router SHOULD NOT send this icmp6 packet due to rate 2743 * limitation. 2744 * 2745 * XXX per-destination/type check necessary? 2746 */ 2747 static int 2748 icmp6_ratelimit(dst, type, code) 2749 const struct in6_addr *dst; /* not used at this moment */ 2750 const int type; /* not used at this moment */ 2751 const int code; /* not used at this moment */ 2752 { 2753 int ret; 2754 2755 ret = 0; /* okay to send */ 2756 2757 /* PPS limit */ 2758 if (!ppsratecheck(&icmp6errppslim_last, &icmp6errpps_count, 2759 icmp6errppslim)) { 2760 /* The packet is subject to rate limit */ 2761 ret++; 2762 } 2763 2764 return ret; 2765 } 2766 2767 static struct rtentry * 2768 icmp6_mtudisc_clone(dst) 2769 struct sockaddr *dst; 2770 { 2771 struct rtentry *rt; 2772 int error; 2773 2774 rt = rtalloc1(dst, 1); 2775 if (rt == 0) 2776 return NULL; 2777 2778 /* If we didn't get a host route, allocate one */ 2779 if ((rt->rt_flags & RTF_HOST) == 0) { 2780 struct rtentry *nrt; 2781 2782 error = rtrequest((int) RTM_ADD, dst, 2783 (struct sockaddr *) rt->rt_gateway, 2784 (struct sockaddr *) 0, 2785 RTF_GATEWAY | RTF_HOST | RTF_DYNAMIC, &nrt); 2786 if (error) { 2787 rtfree(rt); 2788 return NULL; 2789 } 2790 nrt->rt_rmx = rt->rt_rmx; 2791 rtfree(rt); 2792 rt = nrt; 2793 } 2794 error = rt_timer_add(rt, icmp6_mtudisc_timeout, 2795 icmp6_mtudisc_timeout_q); 2796 if (error) { 2797 rtfree(rt); 2798 return NULL; 2799 } 2800 2801 return rt; /* caller need to call rtfree() */ 2802 } 2803 2804 static void 2805 icmp6_mtudisc_timeout(rt, r) 2806 struct rtentry *rt; 2807 struct rttimer *r; 2808 { 2809 if (rt == NULL) 2810 panic("icmp6_mtudisc_timeout: bad route to timeout"); 2811 if ((rt->rt_flags & (RTF_DYNAMIC | RTF_HOST)) == 2812 (RTF_DYNAMIC | RTF_HOST)) { 2813 rtrequest((int) RTM_DELETE, (struct sockaddr *)rt_key(rt), 2814 rt->rt_gateway, rt_mask(rt), rt->rt_flags, 0); 2815 } else { 2816 if (!(rt->rt_rmx.rmx_locks & RTV_MTU)) 2817 rt->rt_rmx.rmx_mtu = 0; 2818 } 2819 } 2820 2821 static void 2822 icmp6_redirect_timeout(rt, r) 2823 struct rtentry *rt; 2824 struct rttimer *r; 2825 { 2826 if (rt == NULL) 2827 panic("icmp6_redirect_timeout: bad route to timeout"); 2828 if ((rt->rt_flags & (RTF_GATEWAY | RTF_DYNAMIC | RTF_HOST)) == 2829 (RTF_GATEWAY | RTF_DYNAMIC | RTF_HOST)) { 2830 rtrequest((int) RTM_DELETE, (struct sockaddr *)rt_key(rt), 2831 rt->rt_gateway, rt_mask(rt), rt->rt_flags, 0); 2832 } 2833 } 2834 2835 /* 2836 * sysctl helper routine for the net.inet6.icmp6.nd6 nodes. silly? 2837 */ 2838 static int 2839 sysctl_net_inet6_icmp6_nd6(SYSCTLFN_ARGS) 2840 { 2841 2842 if (namelen != 0) 2843 return (EINVAL); 2844 2845 return (nd6_sysctl(rnode->sysctl_num, oldp, oldlenp, 2846 /*XXXUNCONST*/ 2847 __UNCONST(newp), newlen)); 2848 } 2849 2850 SYSCTL_SETUP(sysctl_net_inet6_icmp6_setup, 2851 "sysctl net.inet6.icmp6 subtree setup") 2852 { 2853 2854 sysctl_createv(clog, 0, NULL, NULL, 2855 CTLFLAG_PERMANENT, 2856 CTLTYPE_NODE, "net", NULL, 2857 NULL, 0, NULL, 0, 2858 CTL_NET, CTL_EOL); 2859 sysctl_createv(clog, 0, NULL, NULL, 2860 CTLFLAG_PERMANENT, 2861 CTLTYPE_NODE, "inet6", NULL, 2862 NULL, 0, NULL, 0, 2863 CTL_NET, PF_INET6, CTL_EOL); 2864 sysctl_createv(clog, 0, NULL, NULL, 2865 CTLFLAG_PERMANENT, 2866 CTLTYPE_NODE, "icmp6", 2867 SYSCTL_DESCR("ICMPv6 related settings"), 2868 NULL, 0, NULL, 0, 2869 CTL_NET, PF_INET6, IPPROTO_ICMPV6, CTL_EOL); 2870 2871 sysctl_createv(clog, 0, NULL, NULL, 2872 CTLFLAG_PERMANENT, 2873 CTLTYPE_STRUCT, "stats", 2874 SYSCTL_DESCR("ICMPv6 transmission statistics"), 2875 NULL, 0, &icmp6stat, sizeof(icmp6stat), 2876 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2877 ICMPV6CTL_STATS, CTL_EOL); 2878 sysctl_createv(clog, 0, NULL, NULL, 2879 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2880 CTLTYPE_INT, "rediraccept", 2881 SYSCTL_DESCR("Accept and process redirect messages"), 2882 NULL, 0, &icmp6_rediraccept, 0, 2883 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2884 ICMPV6CTL_REDIRACCEPT, CTL_EOL); 2885 sysctl_createv(clog, 0, NULL, NULL, 2886 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2887 CTLTYPE_INT, "redirtimeout", 2888 SYSCTL_DESCR("Redirect generated route lifetime"), 2889 NULL, 0, &icmp6_redirtimeout, 0, 2890 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2891 ICMPV6CTL_REDIRTIMEOUT, CTL_EOL); 2892 #if 0 /* obsoleted */ 2893 sysctl_createv(clog, 0, NULL, NULL, 2894 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2895 CTLTYPE_INT, "errratelimit", NULL, 2896 NULL, 0, &icmp6_errratelimit, 0, 2897 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2898 ICMPV6CTL_ERRRATELIMIT, CTL_EOL); 2899 #endif 2900 sysctl_createv(clog, 0, NULL, NULL, 2901 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2902 CTLTYPE_INT, "nd6_prune", 2903 SYSCTL_DESCR("Neighbor discovery prune interval"), 2904 NULL, 0, &nd6_prune, 0, 2905 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2906 ICMPV6CTL_ND6_PRUNE, CTL_EOL); 2907 sysctl_createv(clog, 0, NULL, NULL, 2908 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2909 CTLTYPE_INT, "nd6_delay", 2910 SYSCTL_DESCR("First probe delay time"), 2911 NULL, 0, &nd6_delay, 0, 2912 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2913 ICMPV6CTL_ND6_DELAY, CTL_EOL); 2914 sysctl_createv(clog, 0, NULL, NULL, 2915 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2916 CTLTYPE_INT, "nd6_umaxtries", 2917 SYSCTL_DESCR("Number of unicast discovery attempts"), 2918 NULL, 0, &nd6_umaxtries, 0, 2919 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2920 ICMPV6CTL_ND6_UMAXTRIES, CTL_EOL); 2921 sysctl_createv(clog, 0, NULL, NULL, 2922 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2923 CTLTYPE_INT, "nd6_mmaxtries", 2924 SYSCTL_DESCR("Number of multicast discovery attempts"), 2925 NULL, 0, &nd6_mmaxtries, 0, 2926 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2927 ICMPV6CTL_ND6_MMAXTRIES, CTL_EOL); 2928 sysctl_createv(clog, 0, NULL, NULL, 2929 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2930 CTLTYPE_INT, "nd6_useloopback", 2931 SYSCTL_DESCR("Use loopback interface for local traffic"), 2932 NULL, 0, &nd6_useloopback, 0, 2933 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2934 ICMPV6CTL_ND6_USELOOPBACK, CTL_EOL); 2935 #if 0 /* obsoleted */ 2936 sysctl_createv(clog, 0, NULL, NULL, 2937 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2938 CTLTYPE_INT, "nd6_proxyall", NULL, 2939 NULL, 0, &nd6_proxyall, 0, 2940 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2941 ICMPV6CTL_ND6_PROXYALL, CTL_EOL); 2942 #endif 2943 sysctl_createv(clog, 0, NULL, NULL, 2944 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2945 CTLTYPE_INT, "nodeinfo", 2946 SYSCTL_DESCR("Respond to node information requests"), 2947 NULL, 0, &icmp6_nodeinfo, 0, 2948 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2949 ICMPV6CTL_NODEINFO, CTL_EOL); 2950 sysctl_createv(clog, 0, NULL, NULL, 2951 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2952 CTLTYPE_INT, "errppslimit", 2953 SYSCTL_DESCR("Maximum ICMP errors sent per second"), 2954 NULL, 0, &icmp6errppslim, 0, 2955 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2956 ICMPV6CTL_ERRPPSLIMIT, CTL_EOL); 2957 sysctl_createv(clog, 0, NULL, NULL, 2958 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2959 CTLTYPE_INT, "nd6_maxnudhint", 2960 SYSCTL_DESCR("Maximum neighbor unreachable hint count"), 2961 NULL, 0, &nd6_maxnudhint, 0, 2962 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2963 ICMPV6CTL_ND6_MAXNUDHINT, CTL_EOL); 2964 sysctl_createv(clog, 0, NULL, NULL, 2965 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2966 CTLTYPE_INT, "mtudisc_hiwat", 2967 SYSCTL_DESCR("Low mark on MTU Discovery route timers"), 2968 NULL, 0, &icmp6_mtudisc_hiwat, 0, 2969 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2970 ICMPV6CTL_MTUDISC_HIWAT, CTL_EOL); 2971 sysctl_createv(clog, 0, NULL, NULL, 2972 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2973 CTLTYPE_INT, "mtudisc_lowat", 2974 SYSCTL_DESCR("Low mark on MTU Discovery route timers"), 2975 NULL, 0, &icmp6_mtudisc_lowat, 0, 2976 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2977 ICMPV6CTL_MTUDISC_LOWAT, CTL_EOL); 2978 sysctl_createv(clog, 0, NULL, NULL, 2979 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2980 CTLTYPE_INT, "nd6_debug", 2981 SYSCTL_DESCR("Enable neighbor discovery debug output"), 2982 NULL, 0, &nd6_debug, 0, 2983 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2984 ICMPV6CTL_ND6_DEBUG, CTL_EOL); 2985 sysctl_createv(clog, 0, NULL, NULL, 2986 CTLFLAG_PERMANENT, 2987 CTLTYPE_STRUCT, "nd6_drlist", 2988 SYSCTL_DESCR("Default router list"), 2989 sysctl_net_inet6_icmp6_nd6, 0, NULL, 0, 2990 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2991 ICMPV6CTL_ND6_DRLIST, CTL_EOL); 2992 sysctl_createv(clog, 0, NULL, NULL, 2993 CTLFLAG_PERMANENT, 2994 CTLTYPE_STRUCT, "nd6_prlist", 2995 SYSCTL_DESCR("Prefix list"), 2996 sysctl_net_inet6_icmp6_nd6, 0, NULL, 0, 2997 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2998 ICMPV6CTL_ND6_PRLIST, CTL_EOL); 2999 } 3000
Indexes created Fri Sep 26 20:09:58 GMT 2025