icmp6.c revision 1.121
1 /* $NetBSD: icmp6.c,v 1.121 2006/09/05 16:11:26 dyoung 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 1.121 2006/09/05 16:11:26 dyoung 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 *)); 165 166 167 void 168 icmp6_init() 169 { 170 mld_init(); 171 icmp6_mtudisc_timeout_q = rt_timer_queue_create(pmtu_expire); 172 icmp6_redirect_timeout_q = rt_timer_queue_create(icmp6_redirtimeout); 173 } 174 175 static void 176 icmp6_errcount(stat, type, code) 177 struct icmp6errstat *stat; 178 int type, code; 179 { 180 switch (type) { 181 case ICMP6_DST_UNREACH: 182 switch (code) { 183 case ICMP6_DST_UNREACH_NOROUTE: 184 stat->icp6errs_dst_unreach_noroute++; 185 return; 186 case ICMP6_DST_UNREACH_ADMIN: 187 stat->icp6errs_dst_unreach_admin++; 188 return; 189 case ICMP6_DST_UNREACH_BEYONDSCOPE: 190 stat->icp6errs_dst_unreach_beyondscope++; 191 return; 192 case ICMP6_DST_UNREACH_ADDR: 193 stat->icp6errs_dst_unreach_addr++; 194 return; 195 case ICMP6_DST_UNREACH_NOPORT: 196 stat->icp6errs_dst_unreach_noport++; 197 return; 198 } 199 break; 200 case ICMP6_PACKET_TOO_BIG: 201 stat->icp6errs_packet_too_big++; 202 return; 203 case ICMP6_TIME_EXCEEDED: 204 switch (code) { 205 case ICMP6_TIME_EXCEED_TRANSIT: 206 stat->icp6errs_time_exceed_transit++; 207 return; 208 case ICMP6_TIME_EXCEED_REASSEMBLY: 209 stat->icp6errs_time_exceed_reassembly++; 210 return; 211 } 212 break; 213 case ICMP6_PARAM_PROB: 214 switch (code) { 215 case ICMP6_PARAMPROB_HEADER: 216 stat->icp6errs_paramprob_header++; 217 return; 218 case ICMP6_PARAMPROB_NEXTHEADER: 219 stat->icp6errs_paramprob_nextheader++; 220 return; 221 case ICMP6_PARAMPROB_OPTION: 222 stat->icp6errs_paramprob_option++; 223 return; 224 } 225 break; 226 case ND_REDIRECT: 227 stat->icp6errs_redirect++; 228 return; 229 } 230 stat->icp6errs_unknown++; 231 } 232 233 /* 234 * Register a Path MTU Discovery callback. 235 */ 236 void 237 icmp6_mtudisc_callback_register(func) 238 void (*func) __P((struct in6_addr *)); 239 { 240 struct icmp6_mtudisc_callback *mc; 241 242 for (mc = LIST_FIRST(&icmp6_mtudisc_callbacks); mc != NULL; 243 mc = LIST_NEXT(mc, mc_list)) { 244 if (mc->mc_func == func) 245 return; 246 } 247 248 mc = malloc(sizeof(*mc), M_PCB, M_NOWAIT); 249 if (mc == NULL) 250 panic("icmp6_mtudisc_callback_register"); 251 252 mc->mc_func = func; 253 LIST_INSERT_HEAD(&icmp6_mtudisc_callbacks, mc, mc_list); 254 } 255 256 /* 257 * A wrapper function for icmp6_error() necessary when the erroneous packet 258 * may not contain enough scope zone information. 259 */ 260 void 261 icmp6_error2(m, type, code, param, ifp) 262 struct mbuf *m; 263 int type, code, param; 264 struct ifnet *ifp; 265 { 266 struct ip6_hdr *ip6; 267 268 if (ifp == NULL) 269 return; 270 271 if (m->m_len < sizeof(struct ip6_hdr)) { 272 m = m_pullup(m, sizeof(struct ip6_hdr)); 273 if (m == NULL) 274 return; 275 } 276 277 ip6 = mtod(m, struct ip6_hdr *); 278 279 if (in6_setscope(&ip6->ip6_src, ifp, NULL) != 0) 280 return; 281 if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0) 282 return; 283 284 icmp6_error(m, type, code, param); 285 } 286 287 /* 288 * Generate an error packet of type error in response to bad IP6 packet. 289 */ 290 void 291 icmp6_error(m, type, code, param) 292 struct mbuf *m; 293 int type, code, param; 294 { 295 struct ip6_hdr *oip6, *nip6; 296 struct icmp6_hdr *icmp6; 297 u_int preplen; 298 int off; 299 int nxt; 300 301 icmp6stat.icp6s_error++; 302 303 /* count per-type-code statistics */ 304 icmp6_errcount(&icmp6stat.icp6s_outerrhist, type, code); 305 306 if (m->m_flags & M_DECRYPTED) { 307 icmp6stat.icp6s_canterror++; 308 goto freeit; 309 } 310 311 if (m->m_len < sizeof(struct ip6_hdr)) { 312 m = m_pullup(m, sizeof(struct ip6_hdr)); 313 if (m == NULL) 314 return; 315 } 316 oip6 = mtod(m, struct ip6_hdr *); 317 318 /* 319 * If the destination address of the erroneous packet is a multicast 320 * address, or the packet was sent using link-layer multicast, 321 * we should basically suppress sending an error (RFC 2463, Section 322 * 2.4). 323 * We have two exceptions (the item e.2 in that section): 324 * - the Pakcet Too Big message can be sent for path MTU discovery. 325 * - the Parameter Problem Message that can be allowed an icmp6 error 326 * in the option type field. This check has been done in 327 * ip6_unknown_opt(), so we can just check the type and code. 328 */ 329 if ((m->m_flags & (M_BCAST|M_MCAST) || 330 IN6_IS_ADDR_MULTICAST(&oip6->ip6_dst)) && 331 (type != ICMP6_PACKET_TOO_BIG && 332 (type != ICMP6_PARAM_PROB || 333 code != ICMP6_PARAMPROB_OPTION))) 334 goto freeit; 335 336 /* 337 * RFC 2463, 2.4 (e.5): source address check. 338 * XXX: the case of anycast source? 339 */ 340 if (IN6_IS_ADDR_UNSPECIFIED(&oip6->ip6_src) || 341 IN6_IS_ADDR_MULTICAST(&oip6->ip6_src)) 342 goto freeit; 343 344 /* 345 * If we are about to send ICMPv6 against ICMPv6 error/redirect, 346 * don't do it. 347 */ 348 nxt = -1; 349 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); 350 if (off >= 0 && nxt == IPPROTO_ICMPV6) { 351 struct icmp6_hdr *icp; 352 353 IP6_EXTHDR_GET(icp, struct icmp6_hdr *, m, off, 354 sizeof(*icp)); 355 if (icp == NULL) { 356 icmp6stat.icp6s_tooshort++; 357 return; 358 } 359 if (icp->icmp6_type < ICMP6_ECHO_REQUEST || 360 icp->icmp6_type == ND_REDIRECT) { 361 /* 362 * ICMPv6 error 363 * Special case: for redirect (which is 364 * informational) we must not send icmp6 error. 365 */ 366 icmp6stat.icp6s_canterror++; 367 goto freeit; 368 } else { 369 /* ICMPv6 informational - send the error */ 370 } 371 } 372 #if 0 /* controversial */ 373 else if (off >= 0 && nxt == IPPROTO_ESP) { 374 /* 375 * It could be ICMPv6 error inside ESP. Take a safer side, 376 * don't respond. 377 */ 378 icmp6stat.icp6s_canterror++; 379 goto freeit; 380 } 381 #endif 382 else { 383 /* non-ICMPv6 - send the error */ 384 } 385 386 oip6 = mtod(m, struct ip6_hdr *); /* adjust pointer */ 387 388 /* Finally, do rate limitation check. */ 389 if (icmp6_ratelimit(&oip6->ip6_src, type, code)) { 390 icmp6stat.icp6s_toofreq++; 391 goto freeit; 392 } 393 394 /* 395 * OK, ICMP6 can be generated. 396 */ 397 398 if (m->m_pkthdr.len >= ICMPV6_PLD_MAXLEN) 399 m_adj(m, ICMPV6_PLD_MAXLEN - m->m_pkthdr.len); 400 401 preplen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 402 M_PREPEND(m, preplen, M_DONTWAIT); 403 if (m && m->m_len < preplen) 404 m = m_pullup(m, preplen); 405 if (m == NULL) { 406 nd6log((LOG_DEBUG, "ENOBUFS in icmp6_error %d\n", __LINE__)); 407 return; 408 } 409 410 nip6 = mtod(m, struct ip6_hdr *); 411 nip6->ip6_src = oip6->ip6_src; 412 nip6->ip6_dst = oip6->ip6_dst; 413 414 in6_clearscope(&oip6->ip6_src); 415 in6_clearscope(&oip6->ip6_dst); 416 417 icmp6 = (struct icmp6_hdr *)(nip6 + 1); 418 icmp6->icmp6_type = type; 419 icmp6->icmp6_code = code; 420 icmp6->icmp6_pptr = htonl((u_int32_t)param); 421 422 /* 423 * icmp6_reflect() is designed to be in the input path. 424 * icmp6_error() can be called from both input and output path, 425 * and if we are in output path rcvif could contain bogus value. 426 * clear m->m_pkthdr.rcvif for safety, we should have enough scope 427 * information in ip header (nip6). 428 */ 429 m->m_pkthdr.rcvif = NULL; 430 431 icmp6stat.icp6s_outhist[type]++; 432 icmp6_reflect(m, sizeof(struct ip6_hdr)); /* header order: IPv6 - ICMPv6 */ 433 434 return; 435 436 freeit: 437 /* 438 * If we can't tell whether or not we can generate ICMP6, free it. 439 */ 440 m_freem(m); 441 } 442 443 /* 444 * Process a received ICMP6 message. 445 */ 446 int 447 icmp6_input(mp, offp, proto) 448 struct mbuf **mp; 449 int *offp, proto; 450 { 451 struct mbuf *m = *mp, *n; 452 struct ip6_hdr *ip6, *nip6; 453 struct icmp6_hdr *icmp6, *nicmp6; 454 int off = *offp; 455 int icmp6len = m->m_pkthdr.len - *offp; 456 int code, sum, noff; 457 458 #define ICMP6_MAXLEN (sizeof(*nip6) + sizeof(*nicmp6) + 4) 459 KASSERT(ICMP6_MAXLEN < MCLBYTES); 460 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_msg); 461 462 /* 463 * Locate icmp6 structure in mbuf, and check 464 * that not corrupted and of at least minimum length 465 */ 466 467 ip6 = mtod(m, struct ip6_hdr *); 468 if (icmp6len < sizeof(struct icmp6_hdr)) { 469 icmp6stat.icp6s_tooshort++; 470 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_error); 471 goto freeit; 472 } 473 474 /* 475 * calculate the checksum 476 */ 477 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 478 if (icmp6 == NULL) { 479 icmp6stat.icp6s_tooshort++; 480 /* m is invalid */ 481 /*icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_error);*/ 482 return IPPROTO_DONE; 483 } 484 KASSERT(IP6_HDR_ALIGNED_P(icmp6)); 485 code = icmp6->icmp6_code; 486 487 if ((sum = in6_cksum(m, IPPROTO_ICMPV6, off, icmp6len)) != 0) { 488 nd6log((LOG_ERR, 489 "ICMP6 checksum error(%d|%x) %s\n", 490 icmp6->icmp6_type, sum, ip6_sprintf(&ip6->ip6_src))); 491 icmp6stat.icp6s_checksum++; 492 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_error); 493 goto freeit; 494 } 495 496 #if defined(NFAITH) && 0 < NFAITH 497 if (faithprefix(&ip6->ip6_dst)) { 498 /* 499 * Deliver very specific ICMP6 type only. 500 * This is important to deliver TOOBIG. Otherwise PMTUD 501 * will not work. 502 */ 503 switch (icmp6->icmp6_type) { 504 case ICMP6_DST_UNREACH: 505 case ICMP6_PACKET_TOO_BIG: 506 case ICMP6_TIME_EXCEEDED: 507 break; 508 default: 509 goto freeit; 510 } 511 } 512 #endif 513 514 icmp6stat.icp6s_inhist[icmp6->icmp6_type]++; 515 516 switch (icmp6->icmp6_type) { 517 case ICMP6_DST_UNREACH: 518 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_dstunreach); 519 switch (code) { 520 case ICMP6_DST_UNREACH_NOROUTE: 521 code = PRC_UNREACH_NET; 522 break; 523 case ICMP6_DST_UNREACH_ADMIN: 524 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_adminprohib); 525 code = PRC_UNREACH_PROTOCOL; /* is this a good code? */ 526 break; 527 case ICMP6_DST_UNREACH_ADDR: 528 code = PRC_HOSTDEAD; 529 break; 530 #ifdef COMPAT_RFC1885 531 case ICMP6_DST_UNREACH_NOTNEIGHBOR: 532 code = PRC_UNREACH_SRCFAIL; 533 break; 534 #else 535 case ICMP6_DST_UNREACH_BEYONDSCOPE: 536 /* I mean "source address was incorrect." */ 537 code = PRC_UNREACH_NET; 538 break; 539 #endif 540 case ICMP6_DST_UNREACH_NOPORT: 541 code = PRC_UNREACH_PORT; 542 break; 543 default: 544 goto badcode; 545 } 546 goto deliver; 547 548 case ICMP6_PACKET_TOO_BIG: 549 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_pkttoobig); 550 551 code = PRC_MSGSIZE; 552 553 /* 554 * Updating the path MTU will be done after examining 555 * intermediate extension headers. 556 */ 557 goto deliver; 558 559 case ICMP6_TIME_EXCEEDED: 560 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_timeexceed); 561 switch (code) { 562 case ICMP6_TIME_EXCEED_TRANSIT: 563 code = PRC_TIMXCEED_INTRANS; 564 break; 565 case ICMP6_TIME_EXCEED_REASSEMBLY: 566 code = PRC_TIMXCEED_REASS; 567 break; 568 default: 569 goto badcode; 570 } 571 goto deliver; 572 573 case ICMP6_PARAM_PROB: 574 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_paramprob); 575 switch (code) { 576 case ICMP6_PARAMPROB_NEXTHEADER: 577 code = PRC_UNREACH_PROTOCOL; 578 break; 579 case ICMP6_PARAMPROB_HEADER: 580 case ICMP6_PARAMPROB_OPTION: 581 code = PRC_PARAMPROB; 582 break; 583 default: 584 goto badcode; 585 } 586 goto deliver; 587 588 case ICMP6_ECHO_REQUEST: 589 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echo); 590 if (code != 0) 591 goto badcode; 592 /* 593 * Copy mbuf to send to two data paths: userland socket(s), 594 * and to the querier (echo reply). 595 * m: a copy for socket, n: a copy for querier 596 * 597 * If the first mbuf is shared, or the first mbuf is too short, 598 * copy the first part of the data into a fresh mbuf. 599 * Otherwise, we will wrongly overwrite both copies. 600 */ 601 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 602 /* Give up local */ 603 n = m; 604 m = NULL; 605 } else if (M_READONLY(n) || 606 n->m_len < off + sizeof(struct icmp6_hdr)) { 607 struct mbuf *n0 = n; 608 609 /* 610 * Prepare an internal mbuf. m_pullup() doesn't 611 * always copy the length we specified. 612 */ 613 if ((n = m_dup(n0, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 614 /* Give up local */ 615 n = m; 616 m = NULL; 617 } 618 m_freem(n0); 619 } 620 nip6 = mtod(n, struct ip6_hdr *); 621 nicmp6 = (struct icmp6_hdr *)((caddr_t)nip6 + off); 622 nicmp6->icmp6_type = ICMP6_ECHO_REPLY; 623 nicmp6->icmp6_code = 0; 624 if (n) { 625 icmp6stat.icp6s_reflect++; 626 icmp6stat.icp6s_outhist[ICMP6_ECHO_REPLY]++; 627 icmp6_reflect(n, off); 628 } 629 if (!m) 630 goto freeit; 631 break; 632 633 case ICMP6_ECHO_REPLY: 634 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echoreply); 635 if (code != 0) 636 goto badcode; 637 break; 638 639 case MLD_LISTENER_QUERY: 640 case MLD_LISTENER_REPORT: 641 if (icmp6len < sizeof(struct mld_hdr)) 642 goto badlen; 643 if (icmp6->icmp6_type == MLD_LISTENER_QUERY) /* XXX: ugly... */ 644 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldquery); 645 else 646 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldreport); 647 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 648 /* give up local */ 649 mld_input(m, off); 650 m = NULL; 651 goto freeit; 652 } 653 mld_input(n, off); 654 /* m stays. */ 655 break; 656 657 case MLD_LISTENER_DONE: 658 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mlddone); 659 if (icmp6len < sizeof(struct mld_hdr)) /* necessary? */ 660 goto badlen; 661 break; /* nothing to be done in kernel */ 662 663 case MLD_MTRACE_RESP: 664 case MLD_MTRACE: 665 /* XXX: these two are experimental. not officially defined. */ 666 /* XXX: per-interface statistics? */ 667 break; /* just pass it to applications */ 668 669 case ICMP6_WRUREQUEST: /* ICMP6_FQDN_QUERY */ 670 { 671 enum { WRU, FQDN } mode; 672 673 if (!icmp6_nodeinfo) 674 break; 675 676 if (icmp6len == sizeof(struct icmp6_hdr) + 4) 677 mode = WRU; 678 else if (icmp6len >= sizeof(struct icmp6_nodeinfo)) 679 mode = FQDN; 680 else 681 goto badlen; 682 683 if (mode == FQDN) { 684 n = m_copym(m, 0, M_COPYALL, M_DONTWAIT); 685 if (n) 686 n = ni6_input(n, off); 687 /* XXX meaningless if n == NULL */ 688 noff = sizeof(struct ip6_hdr); 689 } else { 690 u_char *p; 691 int maxhlen; 692 693 if ((icmp6_nodeinfo & 5) != 5) 694 break; 695 696 if (code != 0) 697 goto badcode; 698 MGETHDR(n, M_DONTWAIT, m->m_type); 699 if (n && ICMP6_MAXLEN > MHLEN) { 700 MCLGET(n, M_DONTWAIT); 701 if ((n->m_flags & M_EXT) == 0) { 702 m_free(n); 703 n = NULL; 704 } 705 } 706 if (n == NULL) { 707 /* Give up remote */ 708 break; 709 } 710 n->m_pkthdr.rcvif = NULL; 711 n->m_len = 0; 712 maxhlen = M_TRAILINGSPACE(n) - ICMP6_MAXLEN; 713 if (maxhlen > hostnamelen) 714 maxhlen = hostnamelen; 715 /* 716 * Copy IPv6 and ICMPv6 only. 717 */ 718 nip6 = mtod(n, struct ip6_hdr *); 719 bcopy(ip6, nip6, sizeof(struct ip6_hdr)); 720 nicmp6 = (struct icmp6_hdr *)(nip6 + 1); 721 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr)); 722 p = (u_char *)(nicmp6 + 1); 723 bzero(p, 4); 724 bcopy(hostname, p + 4, maxhlen); /* meaningless TTL */ 725 noff = sizeof(struct ip6_hdr); 726 M_COPY_PKTHDR(n, m); /* just for rcvif */ 727 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) + 728 sizeof(struct icmp6_hdr) + 4 + maxhlen; 729 nicmp6->icmp6_type = ICMP6_WRUREPLY; 730 nicmp6->icmp6_code = 0; 731 } 732 #undef hostnamelen 733 if (n) { 734 icmp6stat.icp6s_reflect++; 735 icmp6stat.icp6s_outhist[ICMP6_WRUREPLY]++; 736 icmp6_reflect(n, noff); 737 } 738 break; 739 } 740 741 case ICMP6_WRUREPLY: 742 if (code != 0) 743 goto badcode; 744 break; 745 746 case ND_ROUTER_SOLICIT: 747 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routersolicit); 748 if (code != 0) 749 goto badcode; 750 if (icmp6len < sizeof(struct nd_router_solicit)) 751 goto badlen; 752 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 753 /* give up local */ 754 nd6_rs_input(m, off, icmp6len); 755 m = NULL; 756 goto freeit; 757 } 758 nd6_rs_input(n, off, icmp6len); 759 /* m stays. */ 760 break; 761 762 case ND_ROUTER_ADVERT: 763 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routeradvert); 764 if (code != 0) 765 goto badcode; 766 if (icmp6len < sizeof(struct nd_router_advert)) 767 goto badlen; 768 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 769 /* give up local */ 770 nd6_ra_input(m, off, icmp6len); 771 m = NULL; 772 goto freeit; 773 } 774 nd6_ra_input(n, off, icmp6len); 775 /* m stays. */ 776 break; 777 778 case ND_NEIGHBOR_SOLICIT: 779 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighborsolicit); 780 if (code != 0) 781 goto badcode; 782 if (icmp6len < sizeof(struct nd_neighbor_solicit)) 783 goto badlen; 784 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 785 /* give up local */ 786 nd6_ns_input(m, off, icmp6len); 787 m = NULL; 788 goto freeit; 789 } 790 nd6_ns_input(n, off, icmp6len); 791 /* m stays. */ 792 break; 793 794 case ND_NEIGHBOR_ADVERT: 795 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighboradvert); 796 if (code != 0) 797 goto badcode; 798 if (icmp6len < sizeof(struct nd_neighbor_advert)) 799 goto badlen; 800 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 801 /* give up local */ 802 nd6_na_input(m, off, icmp6len); 803 m = NULL; 804 goto freeit; 805 } 806 nd6_na_input(n, off, icmp6len); 807 /* m stays. */ 808 break; 809 810 case ND_REDIRECT: 811 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_redirect); 812 if (code != 0) 813 goto badcode; 814 if (icmp6len < sizeof(struct nd_redirect)) 815 goto badlen; 816 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 817 /* give up local */ 818 icmp6_redirect_input(m, off); 819 m = NULL; 820 goto freeit; 821 } 822 icmp6_redirect_input(n, off); 823 /* m stays. */ 824 break; 825 826 case ICMP6_ROUTER_RENUMBERING: 827 if (code != ICMP6_ROUTER_RENUMBERING_COMMAND && 828 code != ICMP6_ROUTER_RENUMBERING_RESULT) 829 goto badcode; 830 if (icmp6len < sizeof(struct icmp6_router_renum)) 831 goto badlen; 832 break; 833 834 default: 835 nd6log((LOG_DEBUG, 836 "icmp6_input: unknown type %d(src=%s, dst=%s, ifid=%d)\n", 837 icmp6->icmp6_type, ip6_sprintf(&ip6->ip6_src), 838 ip6_sprintf(&ip6->ip6_dst), 839 m->m_pkthdr.rcvif ? m->m_pkthdr.rcvif->if_index : 0)); 840 if (icmp6->icmp6_type < ICMP6_ECHO_REQUEST) { 841 /* ICMPv6 error: MUST deliver it by spec... */ 842 code = PRC_NCMDS; 843 /* deliver */ 844 } else { 845 /* ICMPv6 informational: MUST not deliver */ 846 break; 847 } 848 deliver: 849 if (icmp6_notify_error(m, off, icmp6len, code)) { 850 /* In this case, m should've been freed. */ 851 return (IPPROTO_DONE); 852 } 853 break; 854 855 badcode: 856 icmp6stat.icp6s_badcode++; 857 break; 858 859 badlen: 860 icmp6stat.icp6s_badlen++; 861 break; 862 } 863 864 /* deliver the packet to appropriate sockets */ 865 icmp6_rip6_input(&m, *offp); 866 867 return IPPROTO_DONE; 868 869 freeit: 870 m_freem(m); 871 return IPPROTO_DONE; 872 } 873 874 static int 875 icmp6_notify_error(m, off, icmp6len, code) 876 struct mbuf *m; 877 int off, icmp6len, code; 878 { 879 struct icmp6_hdr *icmp6; 880 struct ip6_hdr *eip6; 881 u_int32_t notifymtu; 882 struct sockaddr_in6 icmp6src, icmp6dst; 883 884 if (icmp6len < sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr)) { 885 icmp6stat.icp6s_tooshort++; 886 goto freeit; 887 } 888 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, 889 sizeof(*icmp6) + sizeof(struct ip6_hdr)); 890 if (icmp6 == NULL) { 891 icmp6stat.icp6s_tooshort++; 892 return (-1); 893 } 894 eip6 = (struct ip6_hdr *)(icmp6 + 1); 895 896 /* Detect the upper level protocol */ 897 { 898 void (*ctlfunc) __P((int, struct sockaddr *, void *)); 899 u_int8_t nxt = eip6->ip6_nxt; 900 int eoff = off + sizeof(struct icmp6_hdr) + 901 sizeof(struct ip6_hdr); 902 struct ip6ctlparam ip6cp; 903 struct in6_addr *finaldst = NULL; 904 int icmp6type = icmp6->icmp6_type; 905 struct ip6_frag *fh; 906 struct ip6_rthdr *rth; 907 struct ip6_rthdr0 *rth0; 908 int rthlen; 909 910 while (1) { /* XXX: should avoid infinite loop explicitly? */ 911 struct ip6_ext *eh; 912 913 switch (nxt) { 914 case IPPROTO_HOPOPTS: 915 case IPPROTO_DSTOPTS: 916 case IPPROTO_AH: 917 IP6_EXTHDR_GET(eh, struct ip6_ext *, m, 918 eoff, sizeof(*eh)); 919 if (eh == NULL) { 920 icmp6stat.icp6s_tooshort++; 921 return (-1); 922 } 923 924 if (nxt == IPPROTO_AH) 925 eoff += (eh->ip6e_len + 2) << 2; 926 else 927 eoff += (eh->ip6e_len + 1) << 3; 928 nxt = eh->ip6e_nxt; 929 break; 930 case IPPROTO_ROUTING: 931 /* 932 * When the erroneous packet contains a 933 * routing header, we should examine the 934 * header to determine the final destination. 935 * Otherwise, we can't properly update 936 * information that depends on the final 937 * destination (e.g. path MTU). 938 */ 939 IP6_EXTHDR_GET(rth, struct ip6_rthdr *, m, 940 eoff, sizeof(*rth)); 941 if (rth == NULL) { 942 icmp6stat.icp6s_tooshort++; 943 return (-1); 944 } 945 rthlen = (rth->ip6r_len + 1) << 3; 946 /* 947 * XXX: currently there is no 948 * officially defined type other 949 * than type-0. 950 * Note that if the segment left field 951 * is 0, all intermediate hops must 952 * have been passed. 953 */ 954 if (rth->ip6r_segleft && 955 rth->ip6r_type == IPV6_RTHDR_TYPE_0) { 956 int hops; 957 958 IP6_EXTHDR_GET(rth0, 959 struct ip6_rthdr0 *, m, 960 eoff, rthlen); 961 if (rth0 == NULL) { 962 icmp6stat.icp6s_tooshort++; 963 return (-1); 964 } 965 /* just ignore a bogus header */ 966 if ((rth0->ip6r0_len % 2) == 0 && 967 (hops = rth0->ip6r0_len/2)) 968 finaldst = (struct in6_addr *)(rth0 + 1) + (hops - 1); 969 } 970 eoff += rthlen; 971 nxt = rth->ip6r_nxt; 972 break; 973 case IPPROTO_FRAGMENT: 974 IP6_EXTHDR_GET(fh, struct ip6_frag *, m, 975 eoff, sizeof(*fh)); 976 if (fh == NULL) { 977 icmp6stat.icp6s_tooshort++; 978 return (-1); 979 } 980 /* 981 * Data after a fragment header is meaningless 982 * unless it is the first fragment, but 983 * we'll go to the notify label for path MTU 984 * discovery. 985 */ 986 if (fh->ip6f_offlg & IP6F_OFF_MASK) 987 goto notify; 988 989 eoff += sizeof(struct ip6_frag); 990 nxt = fh->ip6f_nxt; 991 break; 992 default: 993 /* 994 * This case includes ESP and the No Next 995 * Header. In such cases going to the notify 996 * label does not have any meaning 997 * (i.e. ctlfunc will be NULL), but we go 998 * anyway since we might have to update 999 * path MTU information. 1000 */ 1001 goto notify; 1002 } 1003 } 1004 notify: 1005 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, 1006 sizeof(*icmp6) + sizeof(struct ip6_hdr)); 1007 if (icmp6 == NULL) { 1008 icmp6stat.icp6s_tooshort++; 1009 return (-1); 1010 } 1011 1012 /* 1013 * retrieve parameters from the inner IPv6 header, and convert 1014 * them into sockaddr structures. 1015 * XXX: there is no guarantee that the source or destination 1016 * addresses of the inner packet are in the same scope zone as 1017 * the addresses of the icmp packet. But there is no other 1018 * way to determine the zone. 1019 */ 1020 eip6 = (struct ip6_hdr *)(icmp6 + 1); 1021 1022 bzero(&icmp6dst, sizeof(icmp6dst)); 1023 icmp6dst.sin6_len = sizeof(struct sockaddr_in6); 1024 icmp6dst.sin6_family = AF_INET6; 1025 if (finaldst == NULL) 1026 icmp6dst.sin6_addr = eip6->ip6_dst; 1027 else 1028 icmp6dst.sin6_addr = *finaldst; 1029 if (in6_setscope(&icmp6dst.sin6_addr, m->m_pkthdr.rcvif, NULL)) 1030 goto freeit; 1031 bzero(&icmp6src, sizeof(icmp6src)); 1032 icmp6src.sin6_len = sizeof(struct sockaddr_in6); 1033 icmp6src.sin6_family = AF_INET6; 1034 icmp6src.sin6_addr = eip6->ip6_src; 1035 if (in6_setscope(&icmp6src.sin6_addr, m->m_pkthdr.rcvif, NULL)) 1036 goto freeit; 1037 icmp6src.sin6_flowinfo = 1038 (eip6->ip6_flow & IPV6_FLOWLABEL_MASK); 1039 1040 if (finaldst == NULL) 1041 finaldst = &eip6->ip6_dst; 1042 ip6cp.ip6c_m = m; 1043 ip6cp.ip6c_icmp6 = icmp6; 1044 ip6cp.ip6c_ip6 = (struct ip6_hdr *)(icmp6 + 1); 1045 ip6cp.ip6c_off = eoff; 1046 ip6cp.ip6c_finaldst = finaldst; 1047 ip6cp.ip6c_src = &icmp6src; 1048 ip6cp.ip6c_nxt = nxt; 1049 1050 if (icmp6type == ICMP6_PACKET_TOO_BIG) { 1051 notifymtu = ntohl(icmp6->icmp6_mtu); 1052 ip6cp.ip6c_cmdarg = (void *)¬ifymtu; 1053 } 1054 1055 ctlfunc = (void (*) __P((int, struct sockaddr *, void *))) 1056 (inet6sw[ip6_protox[nxt]].pr_ctlinput); 1057 if (ctlfunc) { 1058 (void) (*ctlfunc)(code, (struct sockaddr *)&icmp6dst, 1059 &ip6cp); 1060 } 1061 } 1062 return (0); 1063 1064 freeit: 1065 m_freem(m); 1066 return (-1); 1067 } 1068 1069 void 1070 icmp6_mtudisc_update(ip6cp, validated) 1071 struct ip6ctlparam *ip6cp; 1072 int validated; 1073 { 1074 unsigned long rtcount; 1075 struct icmp6_mtudisc_callback *mc; 1076 struct in6_addr *dst = ip6cp->ip6c_finaldst; 1077 struct icmp6_hdr *icmp6 = ip6cp->ip6c_icmp6; 1078 struct mbuf *m = ip6cp->ip6c_m; /* will be necessary for scope issue */ 1079 u_int mtu = ntohl(icmp6->icmp6_mtu); 1080 struct rtentry *rt = NULL; 1081 struct sockaddr_in6 sin6; 1082 1083 /* 1084 * allow non-validated cases if memory is plenty, to make traffic 1085 * from non-connected pcb happy. 1086 */ 1087 rtcount = rt_timer_count(icmp6_mtudisc_timeout_q); 1088 if (validated) { 1089 if (0 <= icmp6_mtudisc_hiwat && rtcount > icmp6_mtudisc_hiwat) 1090 return; 1091 else if (0 <= icmp6_mtudisc_lowat && 1092 rtcount > icmp6_mtudisc_lowat) { 1093 /* 1094 * XXX nuke a victim, install the new one. 1095 */ 1096 } 1097 } else { 1098 if (0 <= icmp6_mtudisc_lowat && rtcount > icmp6_mtudisc_lowat) 1099 return; 1100 } 1101 1102 bzero(&sin6, sizeof(sin6)); 1103 sin6.sin6_family = PF_INET6; 1104 sin6.sin6_len = sizeof(struct sockaddr_in6); 1105 sin6.sin6_addr = *dst; 1106 if (in6_setscope(&sin6.sin6_addr, m->m_pkthdr.rcvif, NULL)) 1107 return; 1108 1109 rt = icmp6_mtudisc_clone((struct sockaddr *)&sin6); 1110 1111 if (rt && (rt->rt_flags & RTF_HOST) && 1112 !(rt->rt_rmx.rmx_locks & RTV_MTU) && 1113 (rt->rt_rmx.rmx_mtu > mtu || rt->rt_rmx.rmx_mtu == 0)) { 1114 if (mtu < IN6_LINKMTU(rt->rt_ifp)) { 1115 icmp6stat.icp6s_pmtuchg++; 1116 rt->rt_rmx.rmx_mtu = mtu; 1117 } 1118 } 1119 if (rt) { /* XXX: need braces to avoid conflict with else in RTFREE. */ 1120 RTFREE(rt); 1121 } 1122 1123 /* 1124 * Notify protocols that the MTU for this destination 1125 * has changed. 1126 */ 1127 for (mc = LIST_FIRST(&icmp6_mtudisc_callbacks); mc != NULL; 1128 mc = LIST_NEXT(mc, mc_list)) 1129 (*mc->mc_func)(&sin6.sin6_addr); 1130 } 1131 1132 /* 1133 * Process a Node Information Query packet, based on 1134 * draft-ietf-ipngwg-icmp-name-lookups-07. 1135 * 1136 * Spec incompatibilities: 1137 * - IPv6 Subject address handling 1138 * - IPv4 Subject address handling support missing 1139 * - Proxy reply (answer even if it's not for me) 1140 * - joins NI group address at in6_ifattach() time only, does not cope 1141 * with hostname changes by sethostname(3) 1142 */ 1143 #ifndef offsetof /* XXX */ 1144 #define offsetof(type, member) ((size_t)(&((type *)0)->member)) 1145 #endif 1146 static struct mbuf * 1147 ni6_input(m, off) 1148 struct mbuf *m; 1149 int off; 1150 { 1151 struct icmp6_nodeinfo *ni6, *nni6; 1152 struct mbuf *n = NULL; 1153 u_int16_t qtype; 1154 int subjlen; 1155 int replylen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo); 1156 struct ni_reply_fqdn *fqdn; 1157 int addrs; /* for NI_QTYPE_NODEADDR */ 1158 struct ifnet *ifp = NULL; /* for NI_QTYPE_NODEADDR */ 1159 struct sockaddr_in6 sin6; /* ip6_dst */ 1160 struct in6_addr in6_subj; /* subject address */ 1161 struct ip6_hdr *ip6; 1162 int oldfqdn = 0; /* if 1, return pascal string (03 draft) */ 1163 char *subj = NULL; 1164 1165 ip6 = mtod(m, struct ip6_hdr *); 1166 IP6_EXTHDR_GET(ni6, struct icmp6_nodeinfo *, m, off, sizeof(*ni6)); 1167 if (ni6 == NULL) { 1168 /* m is already reclaimed */ 1169 return NULL; 1170 } 1171 1172 /* 1173 * Validate IPv6 destination address. 1174 * 1175 * The Responder must discard the Query without further processing 1176 * unless it is one of the Responder's unicast or anycast addresses, or 1177 * a link-local scope multicast address which the Responder has joined. 1178 * [icmp-name-lookups-07, Section 4.] 1179 */ 1180 bzero(&sin6, sizeof(sin6)); 1181 sin6.sin6_family = AF_INET6; 1182 sin6.sin6_len = sizeof(struct sockaddr_in6); 1183 bcopy(&ip6->ip6_dst, &sin6.sin6_addr, sizeof(sin6.sin6_addr)); 1184 /* XXX scopeid */ 1185 if (ifa_ifwithaddr((struct sockaddr *)&sin6)) 1186 ; /* unicast/anycast, fine */ 1187 else if (IN6_IS_ADDR_MC_LINKLOCAL(&sin6.sin6_addr)) 1188 ; /* link-local multicast, fine */ 1189 else 1190 goto bad; 1191 1192 /* validate query Subject field. */ 1193 qtype = ntohs(ni6->ni_qtype); 1194 subjlen = m->m_pkthdr.len - off - sizeof(struct icmp6_nodeinfo); 1195 switch (qtype) { 1196 case NI_QTYPE_NOOP: 1197 case NI_QTYPE_SUPTYPES: 1198 /* 07 draft */ 1199 if (ni6->ni_code == ICMP6_NI_SUBJ_FQDN && subjlen == 0) 1200 break; 1201 /* FALLTHROUGH */ 1202 case NI_QTYPE_FQDN: 1203 case NI_QTYPE_NODEADDR: 1204 case NI_QTYPE_IPV4ADDR: 1205 switch (ni6->ni_code) { 1206 case ICMP6_NI_SUBJ_IPV6: 1207 #if ICMP6_NI_SUBJ_IPV6 != 0 1208 case 0: 1209 #endif 1210 /* 1211 * backward compatibility - try to accept 03 draft 1212 * format, where no Subject is present. 1213 */ 1214 if (qtype == NI_QTYPE_FQDN && ni6->ni_code == 0 && 1215 subjlen == 0) { 1216 oldfqdn++; 1217 break; 1218 } 1219 #if ICMP6_NI_SUBJ_IPV6 != 0 1220 if (ni6->ni_code != ICMP6_NI_SUBJ_IPV6) 1221 goto bad; 1222 #endif 1223 1224 if (subjlen != sizeof(sin6.sin6_addr)) 1225 goto bad; 1226 1227 /* 1228 * Validate Subject address. 1229 * 1230 * Not sure what exactly "address belongs to the node" 1231 * means in the spec, is it just unicast, or what? 1232 * 1233 * At this moment we consider Subject address as 1234 * "belong to the node" if the Subject address equals 1235 * to the IPv6 destination address; validation for 1236 * IPv6 destination address should have done enough 1237 * check for us. 1238 * 1239 * We do not do proxy at this moment. 1240 */ 1241 /* m_pulldown instead of copy? */ 1242 m_copydata(m, off + sizeof(struct icmp6_nodeinfo), 1243 subjlen, (caddr_t)&in6_subj); 1244 if (in6_setscope(&in6_subj, m->m_pkthdr.rcvif, NULL)) 1245 goto bad; 1246 1247 subj = (char *)&in6_subj; 1248 if (IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, &in6_subj)) 1249 break; 1250 1251 /* 1252 * XXX if we are to allow other cases, we should really 1253 * be careful about scope here. 1254 * basically, we should disallow queries toward IPv6 1255 * destination X with subject Y, if scope(X) > scope(Y). 1256 * if we allow scope(X) > scope(Y), it will result in 1257 * information leakage across scope boundary. 1258 */ 1259 goto bad; 1260 1261 case ICMP6_NI_SUBJ_FQDN: 1262 /* 1263 * Validate Subject name with gethostname(3). 1264 * 1265 * The behavior may need some debate, since: 1266 * - we are not sure if the node has FQDN as 1267 * hostname (returned by gethostname(3)). 1268 * - the code does wildcard match for truncated names. 1269 * however, we are not sure if we want to perform 1270 * wildcard match, if gethostname(3) side has 1271 * truncated hostname. 1272 */ 1273 n = ni6_nametodns(hostname, hostnamelen, 0); 1274 if (!n || n->m_next || n->m_len == 0) 1275 goto bad; 1276 IP6_EXTHDR_GET(subj, char *, m, 1277 off + sizeof(struct icmp6_nodeinfo), subjlen); 1278 if (subj == NULL) 1279 goto bad; 1280 if (!ni6_dnsmatch(subj, subjlen, mtod(n, const char *), 1281 n->m_len)) { 1282 goto bad; 1283 } 1284 m_freem(n); 1285 n = NULL; 1286 break; 1287 1288 case ICMP6_NI_SUBJ_IPV4: /* XXX: to be implemented? */ 1289 default: 1290 goto bad; 1291 } 1292 break; 1293 } 1294 1295 /* refuse based on configuration. XXX ICMP6_NI_REFUSED? */ 1296 switch (qtype) { 1297 case NI_QTYPE_FQDN: 1298 if ((icmp6_nodeinfo & 1) == 0) 1299 goto bad; 1300 break; 1301 case NI_QTYPE_NODEADDR: 1302 case NI_QTYPE_IPV4ADDR: 1303 if ((icmp6_nodeinfo & 2) == 0) 1304 goto bad; 1305 break; 1306 } 1307 1308 /* guess reply length */ 1309 switch (qtype) { 1310 case NI_QTYPE_NOOP: 1311 break; /* no reply data */ 1312 case NI_QTYPE_SUPTYPES: 1313 replylen += sizeof(u_int32_t); 1314 break; 1315 case NI_QTYPE_FQDN: 1316 /* XXX will append an mbuf */ 1317 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1318 break; 1319 case NI_QTYPE_NODEADDR: 1320 addrs = ni6_addrs(ni6, m, &ifp, subj); 1321 if ((replylen += addrs * (sizeof(struct in6_addr) + 1322 sizeof(u_int32_t))) > MCLBYTES) 1323 replylen = MCLBYTES; /* XXX: will truncate pkt later */ 1324 break; 1325 case NI_QTYPE_IPV4ADDR: 1326 /* unsupported - should respond with unknown Qtype? */ 1327 goto bad; 1328 default: 1329 /* 1330 * XXX: We must return a reply with the ICMP6 code 1331 * `unknown Qtype' in this case. However we regard the case 1332 * as an FQDN query for backward compatibility. 1333 * Older versions set a random value to this field, 1334 * so it rarely varies in the defined qtypes. 1335 * But the mechanism is not reliable... 1336 * maybe we should obsolete older versions. 1337 */ 1338 qtype = NI_QTYPE_FQDN; 1339 /* XXX will append an mbuf */ 1340 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1341 oldfqdn++; 1342 break; 1343 } 1344 1345 /* allocate an mbuf to reply. */ 1346 MGETHDR(n, M_DONTWAIT, m->m_type); 1347 if (n == NULL) { 1348 m_freem(m); 1349 return (NULL); 1350 } 1351 M_MOVE_PKTHDR(n, m); /* just for rcvif */ 1352 if (replylen > MHLEN) { 1353 if (replylen > MCLBYTES) { 1354 /* 1355 * XXX: should we try to allocate more? But MCLBYTES 1356 * is probably much larger than IPV6_MMTU... 1357 */ 1358 goto bad; 1359 } 1360 MCLGET(n, M_DONTWAIT); 1361 if ((n->m_flags & M_EXT) == 0) { 1362 goto bad; 1363 } 1364 } 1365 n->m_pkthdr.len = n->m_len = replylen; 1366 1367 /* copy mbuf header and IPv6 + Node Information base headers */ 1368 bcopy(mtod(m, caddr_t), mtod(n, caddr_t), sizeof(struct ip6_hdr)); 1369 nni6 = (struct icmp6_nodeinfo *)(mtod(n, struct ip6_hdr *) + 1); 1370 bcopy((caddr_t)ni6, (caddr_t)nni6, sizeof(struct icmp6_nodeinfo)); 1371 1372 /* qtype dependent procedure */ 1373 switch (qtype) { 1374 case NI_QTYPE_NOOP: 1375 nni6->ni_code = ICMP6_NI_SUCCESS; 1376 nni6->ni_flags = 0; 1377 break; 1378 case NI_QTYPE_SUPTYPES: 1379 { 1380 u_int32_t v; 1381 nni6->ni_code = ICMP6_NI_SUCCESS; 1382 nni6->ni_flags = htons(0x0000); /* raw bitmap */ 1383 /* supports NOOP, SUPTYPES, FQDN, and NODEADDR */ 1384 v = (u_int32_t)htonl(0x0000000f); 1385 bcopy(&v, nni6 + 1, sizeof(u_int32_t)); 1386 break; 1387 } 1388 case NI_QTYPE_FQDN: 1389 nni6->ni_code = ICMP6_NI_SUCCESS; 1390 fqdn = (struct ni_reply_fqdn *)(mtod(n, caddr_t) + 1391 sizeof(struct ip6_hdr) + 1392 sizeof(struct icmp6_nodeinfo)); 1393 nni6->ni_flags = 0; /* XXX: meaningless TTL */ 1394 fqdn->ni_fqdn_ttl = 0; /* ditto. */ 1395 /* 1396 * XXX do we really have FQDN in variable "hostname"? 1397 */ 1398 n->m_next = ni6_nametodns(hostname, hostnamelen, oldfqdn); 1399 if (n->m_next == NULL) 1400 goto bad; 1401 /* XXX we assume that n->m_next is not a chain */ 1402 if (n->m_next->m_next != NULL) 1403 goto bad; 1404 n->m_pkthdr.len += n->m_next->m_len; 1405 break; 1406 case NI_QTYPE_NODEADDR: 1407 { 1408 int lenlim, copied; 1409 1410 nni6->ni_code = ICMP6_NI_SUCCESS; 1411 n->m_pkthdr.len = n->m_len = 1412 sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo); 1413 lenlim = M_TRAILINGSPACE(n); 1414 copied = ni6_store_addrs(ni6, nni6, ifp, lenlim); 1415 /* XXX: reset mbuf length */ 1416 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) + 1417 sizeof(struct icmp6_nodeinfo) + copied; 1418 break; 1419 } 1420 default: 1421 break; /* XXX impossible! */ 1422 } 1423 1424 nni6->ni_type = ICMP6_NI_REPLY; 1425 m_freem(m); 1426 return (n); 1427 1428 bad: 1429 m_freem(m); 1430 if (n) 1431 m_freem(n); 1432 return (NULL); 1433 } 1434 #undef hostnamelen 1435 1436 #define isupper(x) ('A' <= (x) && (x) <= 'Z') 1437 #define isalpha(x) (('A' <= (x) && (x) <= 'Z') || ('a' <= (x) && (x) <= 'z')) 1438 #define isalnum(x) (isalpha(x) || ('0' <= (x) && (x) <= '9')) 1439 #define tolower(x) (isupper(x) ? (x) + 'a' - 'A' : (x)) 1440 1441 /* 1442 * make a mbuf with DNS-encoded string. no compression support. 1443 * 1444 * XXX names with less than 2 dots (like "foo" or "foo.section") will be 1445 * treated as truncated name (two \0 at the end). this is a wild guess. 1446 */ 1447 static struct mbuf * 1448 ni6_nametodns(name, namelen, old) 1449 const char *name; 1450 int namelen; 1451 int old; /* return pascal string if non-zero */ 1452 { 1453 struct mbuf *m; 1454 char *cp, *ep; 1455 const char *p, *q; 1456 int i, len, nterm; 1457 1458 if (old) 1459 len = namelen + 1; 1460 else 1461 len = MCLBYTES; 1462 1463 /* because MAXHOSTNAMELEN is usually 256, we use cluster mbuf */ 1464 MGET(m, M_DONTWAIT, MT_DATA); 1465 if (m && len > MLEN) { 1466 MCLGET(m, M_DONTWAIT); 1467 if ((m->m_flags & M_EXT) == 0) 1468 goto fail; 1469 } 1470 if (!m) 1471 goto fail; 1472 m->m_next = NULL; 1473 1474 if (old) { 1475 m->m_len = len; 1476 *mtod(m, char *) = namelen; 1477 bcopy(name, mtod(m, char *) + 1, namelen); 1478 return m; 1479 } else { 1480 m->m_len = 0; 1481 cp = mtod(m, char *); 1482 ep = mtod(m, char *) + M_TRAILINGSPACE(m); 1483 1484 /* if not certain about my name, return empty buffer */ 1485 if (namelen == 0) 1486 return m; 1487 1488 /* 1489 * guess if it looks like shortened hostname, or FQDN. 1490 * shortened hostname needs two trailing "\0". 1491 */ 1492 i = 0; 1493 for (p = name; p < name + namelen; p++) { 1494 if (*p && *p == '.') 1495 i++; 1496 } 1497 if (i < 2) 1498 nterm = 2; 1499 else 1500 nterm = 1; 1501 1502 p = name; 1503 while (cp < ep && p < name + namelen) { 1504 i = 0; 1505 for (q = p; q < name + namelen && *q && *q != '.'; q++) 1506 i++; 1507 /* result does not fit into mbuf */ 1508 if (cp + i + 1 >= ep) 1509 goto fail; 1510 /* 1511 * DNS label length restriction, RFC1035 page 8. 1512 * "i == 0" case is included here to avoid returning 1513 * 0-length label on "foo..bar". 1514 */ 1515 if (i <= 0 || i >= 64) 1516 goto fail; 1517 *cp++ = i; 1518 if (!isalpha(p[0]) || !isalnum(p[i - 1])) 1519 goto fail; 1520 while (i > 0) { 1521 if (!isalnum(*p) && *p != '-') 1522 goto fail; 1523 if (isupper(*p)) { 1524 *cp++ = tolower(*p); 1525 p++; 1526 } else 1527 *cp++ = *p++; 1528 i--; 1529 } 1530 p = q; 1531 if (p < name + namelen && *p == '.') 1532 p++; 1533 } 1534 /* termination */ 1535 if (cp + nterm >= ep) 1536 goto fail; 1537 while (nterm-- > 0) 1538 *cp++ = '\0'; 1539 m->m_len = cp - mtod(m, char *); 1540 return m; 1541 } 1542 1543 panic("should not reach here"); 1544 /* NOTREACHED */ 1545 1546 fail: 1547 if (m) 1548 m_freem(m); 1549 return NULL; 1550 } 1551 1552 /* 1553 * check if two DNS-encoded string matches. takes care of truncated 1554 * form (with \0\0 at the end). no compression support. 1555 * XXX upper/lowercase match (see RFC2065) 1556 */ 1557 static int 1558 ni6_dnsmatch(a, alen, b, blen) 1559 const char *a; 1560 int alen; 1561 const char *b; 1562 int blen; 1563 { 1564 const char *a0, *b0; 1565 int l; 1566 1567 /* simplest case - need validation? */ 1568 if (alen == blen && bcmp(a, b, alen) == 0) 1569 return 1; 1570 1571 a0 = a; 1572 b0 = b; 1573 1574 /* termination is mandatory */ 1575 if (alen < 2 || blen < 2) 1576 return 0; 1577 if (a0[alen - 1] != '\0' || b0[blen - 1] != '\0') 1578 return 0; 1579 alen--; 1580 blen--; 1581 1582 while (a - a0 < alen && b - b0 < blen) { 1583 if (a - a0 + 1 > alen || b - b0 + 1 > blen) 1584 return 0; 1585 1586 if ((signed char)a[0] < 0 || (signed char)b[0] < 0) 1587 return 0; 1588 /* we don't support compression yet */ 1589 if (a[0] >= 64 || b[0] >= 64) 1590 return 0; 1591 1592 /* truncated case */ 1593 if (a[0] == 0 && a - a0 == alen - 1) 1594 return 1; 1595 if (b[0] == 0 && b - b0 == blen - 1) 1596 return 1; 1597 if (a[0] == 0 || b[0] == 0) 1598 return 0; 1599 1600 if (a[0] != b[0]) 1601 return 0; 1602 l = a[0]; 1603 if (a - a0 + 1 + l > alen || b - b0 + 1 + l > blen) 1604 return 0; 1605 if (bcmp(a + 1, b + 1, l) != 0) 1606 return 0; 1607 1608 a += 1 + l; 1609 b += 1 + l; 1610 } 1611 1612 if (a - a0 == alen && b - b0 == blen) 1613 return 1; 1614 else 1615 return 0; 1616 } 1617 1618 /* 1619 * calculate the number of addresses to be returned in the node info reply. 1620 */ 1621 static int 1622 ni6_addrs(ni6, m, ifpp, subj) 1623 struct icmp6_nodeinfo *ni6; 1624 struct mbuf *m; 1625 struct ifnet **ifpp; 1626 char *subj; 1627 { 1628 struct ifnet *ifp; 1629 struct in6_ifaddr *ifa6; 1630 struct ifaddr *ifa; 1631 struct sockaddr_in6 *subj_ip6 = NULL; /* XXX pedant */ 1632 int addrs = 0, addrsofif, iffound = 0; 1633 int niflags = ni6->ni_flags; 1634 1635 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0) { 1636 switch (ni6->ni_code) { 1637 case ICMP6_NI_SUBJ_IPV6: 1638 if (subj == NULL) /* must be impossible... */ 1639 return (0); 1640 subj_ip6 = (struct sockaddr_in6 *)subj; 1641 break; 1642 default: 1643 /* 1644 * XXX: we only support IPv6 subject address for 1645 * this Qtype. 1646 */ 1647 return (0); 1648 } 1649 } 1650 1651 for (ifp = TAILQ_FIRST(&ifnet); ifp; ifp = TAILQ_NEXT(ifp, if_list)) 1652 { 1653 addrsofif = 0; 1654 for (ifa = ifp->if_addrlist.tqh_first; ifa; 1655 ifa = ifa->ifa_list.tqe_next) 1656 { 1657 if (ifa->ifa_addr->sa_family != AF_INET6) 1658 continue; 1659 ifa6 = (struct in6_ifaddr *)ifa; 1660 1661 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0 && 1662 IN6_ARE_ADDR_EQUAL(&subj_ip6->sin6_addr, 1663 &ifa6->ia_addr.sin6_addr)) 1664 iffound = 1; 1665 1666 /* 1667 * IPv4-mapped addresses can only be returned by a 1668 * Node Information proxy, since they represent 1669 * addresses of IPv4-only nodes, which perforce do 1670 * not implement this protocol. 1671 * [icmp-name-lookups-07, Section 5.4] 1672 * So we don't support NI_NODEADDR_FLAG_COMPAT in 1673 * this function at this moment. 1674 */ 1675 1676 /* What do we have to do about ::1? */ 1677 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1678 case IPV6_ADDR_SCOPE_LINKLOCAL: 1679 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0) 1680 continue; 1681 break; 1682 case IPV6_ADDR_SCOPE_SITELOCAL: 1683 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0) 1684 continue; 1685 break; 1686 case IPV6_ADDR_SCOPE_GLOBAL: 1687 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0) 1688 continue; 1689 break; 1690 default: 1691 continue; 1692 } 1693 1694 /* 1695 * check if anycast is okay. 1696 * XXX: just experimental. not in the spec. 1697 */ 1698 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 && 1699 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0) 1700 continue; /* we need only unicast addresses */ 1701 1702 addrsofif++; /* count the address */ 1703 } 1704 if (iffound) { 1705 *ifpp = ifp; 1706 return (addrsofif); 1707 } 1708 1709 addrs += addrsofif; 1710 } 1711 1712 return (addrs); 1713 } 1714 1715 static int 1716 ni6_store_addrs(ni6, nni6, ifp0, resid) 1717 struct icmp6_nodeinfo *ni6, *nni6; 1718 struct ifnet *ifp0; 1719 int resid; 1720 { 1721 struct ifnet *ifp = ifp0 ? ifp0 : TAILQ_FIRST(&ifnet); 1722 struct in6_ifaddr *ifa6; 1723 struct ifaddr *ifa; 1724 struct ifnet *ifp_dep = NULL; 1725 int copied = 0, allow_deprecated = 0; 1726 u_char *cp = (u_char *)(nni6 + 1); 1727 int niflags = ni6->ni_flags; 1728 u_int32_t ltime; 1729 1730 if (ifp0 == NULL && !(niflags & NI_NODEADDR_FLAG_ALL)) 1731 return (0); /* needless to copy */ 1732 1733 again: 1734 1735 for (; ifp; ifp = TAILQ_NEXT(ifp, if_list)) 1736 { 1737 for (ifa = ifp->if_addrlist.tqh_first; ifa; 1738 ifa = ifa->ifa_list.tqe_next) 1739 { 1740 if (ifa->ifa_addr->sa_family != AF_INET6) 1741 continue; 1742 ifa6 = (struct in6_ifaddr *)ifa; 1743 1744 if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) != 0 && 1745 allow_deprecated == 0) { 1746 /* 1747 * prefererred address should be put before 1748 * deprecated addresses. 1749 */ 1750 1751 /* record the interface for later search */ 1752 if (ifp_dep == NULL) 1753 ifp_dep = ifp; 1754 1755 continue; 1756 } 1757 else if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) == 0 && 1758 allow_deprecated != 0) 1759 continue; /* we now collect deprecated addrs */ 1760 1761 /* What do we have to do about ::1? */ 1762 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1763 case IPV6_ADDR_SCOPE_LINKLOCAL: 1764 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0) 1765 continue; 1766 break; 1767 case IPV6_ADDR_SCOPE_SITELOCAL: 1768 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0) 1769 continue; 1770 break; 1771 case IPV6_ADDR_SCOPE_GLOBAL: 1772 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0) 1773 continue; 1774 break; 1775 default: 1776 continue; 1777 } 1778 1779 /* 1780 * check if anycast is okay. 1781 * XXX: just experimental. not in the spec. 1782 */ 1783 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 && 1784 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0) 1785 continue; 1786 1787 /* now we can copy the address */ 1788 if (resid < sizeof(struct in6_addr) + 1789 sizeof(u_int32_t)) { 1790 /* 1791 * We give up much more copy. 1792 * Set the truncate flag and return. 1793 */ 1794 nni6->ni_flags |= NI_NODEADDR_FLAG_TRUNCATE; 1795 return (copied); 1796 } 1797 1798 /* 1799 * Set the TTL of the address. 1800 * The TTL value should be one of the following 1801 * according to the specification: 1802 * 1803 * 1. The remaining lifetime of a DHCP lease on the 1804 * address, or 1805 * 2. The remaining Valid Lifetime of a prefix from 1806 * which the address was derived through Stateless 1807 * Autoconfiguration. 1808 * 1809 * Note that we currently do not support stateful 1810 * address configuration by DHCPv6, so the former 1811 * case can't happen. 1812 * 1813 * TTL must be 2^31 > TTL >= 0. 1814 */ 1815 if (ifa6->ia6_lifetime.ia6t_expire == 0) 1816 ltime = ND6_INFINITE_LIFETIME; 1817 else { 1818 if (ifa6->ia6_lifetime.ia6t_expire > 1819 time_second) 1820 ltime = ifa6->ia6_lifetime.ia6t_expire - 1821 time_second; 1822 else 1823 ltime = 0; 1824 } 1825 if (ltime > 0x7fffffff) 1826 ltime = 0x7fffffff; 1827 ltime = htonl(ltime); 1828 1829 bcopy(<ime, cp, sizeof(u_int32_t)); 1830 cp += sizeof(u_int32_t); 1831 1832 /* copy the address itself */ 1833 bcopy(&ifa6->ia_addr.sin6_addr, cp, 1834 sizeof(struct in6_addr)); 1835 in6_clearscope((struct in6_addr *)cp); /* XXX */ 1836 cp += sizeof(struct in6_addr); 1837 1838 resid -= (sizeof(struct in6_addr) + sizeof(u_int32_t)); 1839 copied += (sizeof(struct in6_addr) + sizeof(u_int32_t)); 1840 } 1841 if (ifp0) /* we need search only on the specified IF */ 1842 break; 1843 } 1844 1845 if (allow_deprecated == 0 && ifp_dep != NULL) { 1846 ifp = ifp_dep; 1847 allow_deprecated = 1; 1848 1849 goto again; 1850 } 1851 1852 return (copied); 1853 } 1854 1855 /* 1856 * XXX almost dup'ed code with rip6_input. 1857 */ 1858 static int 1859 icmp6_rip6_input(mp, off) 1860 struct mbuf **mp; 1861 int off; 1862 { 1863 struct mbuf *m = *mp; 1864 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1865 struct inpcb_hdr *inph; 1866 struct in6pcb *in6p; 1867 struct in6pcb *last = NULL; 1868 struct sockaddr_in6 rip6src; 1869 struct icmp6_hdr *icmp6; 1870 struct mbuf *opts = NULL; 1871 1872 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 1873 if (icmp6 == NULL) { 1874 /* m is already reclaimed */ 1875 return IPPROTO_DONE; 1876 } 1877 1878 /* 1879 * XXX: the address may have embedded scope zone ID, which should be 1880 * hidden from applications. 1881 */ 1882 bzero(&rip6src, sizeof(rip6src)); 1883 rip6src.sin6_len = sizeof(struct sockaddr_in6); 1884 rip6src.sin6_family = AF_INET6; 1885 rip6src.sin6_addr = ip6->ip6_src; 1886 if (sa6_recoverscope(&rip6src)) { 1887 m_freem(m); 1888 return (IPPROTO_DONE); 1889 } 1890 1891 CIRCLEQ_FOREACH(inph, &raw6cbtable.inpt_queue, inph_queue) { 1892 in6p = (struct in6pcb *)inph; 1893 if (in6p->in6p_af != AF_INET6) 1894 continue; 1895 if (in6p->in6p_ip6.ip6_nxt != IPPROTO_ICMPV6) 1896 continue; 1897 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr) && 1898 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr, &ip6->ip6_dst)) 1899 continue; 1900 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr) && 1901 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr, &ip6->ip6_src)) 1902 continue; 1903 if (in6p->in6p_icmp6filt 1904 && ICMP6_FILTER_WILLBLOCK(icmp6->icmp6_type, 1905 in6p->in6p_icmp6filt)) 1906 continue; 1907 if (last) { 1908 struct mbuf *n; 1909 if ((n = m_copy(m, 0, (int)M_COPYALL)) != NULL) { 1910 if (last->in6p_flags & IN6P_CONTROLOPTS) 1911 ip6_savecontrol(last, &opts, ip6, n); 1912 /* strip intermediate headers */ 1913 m_adj(n, off); 1914 if (sbappendaddr(&last->in6p_socket->so_rcv, 1915 (struct sockaddr *)&rip6src, 1916 n, opts) == 0) { 1917 /* should notify about lost packet */ 1918 m_freem(n); 1919 if (opts) 1920 m_freem(opts); 1921 } else 1922 sorwakeup(last->in6p_socket); 1923 opts = NULL; 1924 } 1925 } 1926 last = in6p; 1927 } 1928 if (last) { 1929 if (last->in6p_flags & IN6P_CONTROLOPTS) 1930 ip6_savecontrol(last, &opts, ip6, m); 1931 /* strip intermediate headers */ 1932 m_adj(m, off); 1933 if (sbappendaddr(&last->in6p_socket->so_rcv, 1934 (struct sockaddr *)&rip6src, m, opts) == 0) { 1935 m_freem(m); 1936 if (opts) 1937 m_freem(opts); 1938 } else 1939 sorwakeup(last->in6p_socket); 1940 } else { 1941 m_freem(m); 1942 ip6stat.ip6s_delivered--; 1943 } 1944 return IPPROTO_DONE; 1945 } 1946 1947 /* 1948 * Reflect the ip6 packet back to the source. 1949 * OFF points to the icmp6 header, counted from the top of the mbuf. 1950 * 1951 * Note: RFC 1885 required that an echo reply should be truncated if it 1952 * did not fit in with (return) path MTU, and KAME code supported the 1953 * behavior. However, as a clarification after the RFC, this limitation 1954 * was removed in a revised version of the spec, RFC 2463. We had kept the 1955 * old behavior, with a (non-default) ifdef block, while the new version of 1956 * the spec was an internet-draft status, and even after the new RFC was 1957 * published. But it would rather make sense to clean the obsoleted part 1958 * up, and to make the code simpler at this stage. 1959 */ 1960 void 1961 icmp6_reflect(m, off) 1962 struct mbuf *m; 1963 size_t off; 1964 { 1965 struct ip6_hdr *ip6; 1966 struct icmp6_hdr *icmp6; 1967 struct in6_ifaddr *ia; 1968 int plen; 1969 int type, code; 1970 struct ifnet *outif = NULL; 1971 struct in6_addr origdst, *src = NULL; 1972 1973 /* too short to reflect */ 1974 if (off < sizeof(struct ip6_hdr)) { 1975 nd6log((LOG_DEBUG, 1976 "sanity fail: off=%lx, sizeof(ip6)=%lx in %s:%d\n", 1977 (u_long)off, (u_long)sizeof(struct ip6_hdr), 1978 __FILE__, __LINE__)); 1979 goto bad; 1980 } 1981 1982 /* 1983 * If there are extra headers between IPv6 and ICMPv6, strip 1984 * off that header first. 1985 */ 1986 #ifdef DIAGNOSTIC 1987 if (sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) > MHLEN) 1988 panic("assumption failed in icmp6_reflect"); 1989 #endif 1990 if (off > sizeof(struct ip6_hdr)) { 1991 size_t l; 1992 struct ip6_hdr nip6; 1993 1994 l = off - sizeof(struct ip6_hdr); 1995 m_copydata(m, 0, sizeof(nip6), (caddr_t)&nip6); 1996 m_adj(m, l); 1997 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 1998 if (m->m_len < l) { 1999 if ((m = m_pullup(m, l)) == NULL) 2000 return; 2001 } 2002 bcopy((caddr_t)&nip6, mtod(m, caddr_t), sizeof(nip6)); 2003 } else /* off == sizeof(struct ip6_hdr) */ { 2004 size_t l; 2005 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 2006 if (m->m_len < l) { 2007 if ((m = m_pullup(m, l)) == NULL) 2008 return; 2009 } 2010 } 2011 plen = m->m_pkthdr.len - sizeof(struct ip6_hdr); 2012 ip6 = mtod(m, struct ip6_hdr *); 2013 ip6->ip6_nxt = IPPROTO_ICMPV6; 2014 icmp6 = (struct icmp6_hdr *)(ip6 + 1); 2015 type = icmp6->icmp6_type; /* keep type for statistics */ 2016 code = icmp6->icmp6_code; /* ditto. */ 2017 2018 origdst = ip6->ip6_dst; 2019 /* 2020 * ip6_input() drops a packet if its src is multicast. 2021 * So, the src is never multicast. 2022 */ 2023 ip6->ip6_dst = ip6->ip6_src; 2024 2025 /* 2026 * If the incoming packet was addressed directly to us (i.e. unicast), 2027 * use dst as the src for the reply. 2028 * The IN6_IFF_NOTREADY case should be VERY rare, but is possible 2029 * (for example) when we encounter an error while forwarding procedure 2030 * destined to a duplicated address of ours. 2031 * Note that ip6_getdstifaddr() may fail if we are in an error handling 2032 * procedure of an outgoing packet of our own, in which case we need 2033 * to search in the ifaddr list. 2034 */ 2035 if (!IN6_IS_ADDR_MULTICAST(&origdst)) { 2036 if ((ia = ip6_getdstifaddr(m))) { 2037 if (!(ia->ia6_flags & 2038 (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY))) 2039 src = &ia->ia_addr.sin6_addr; 2040 } else { 2041 struct sockaddr_in6 d; 2042 2043 bzero(&d, sizeof(d)); 2044 d.sin6_family = AF_INET6; 2045 d.sin6_len = sizeof(d); 2046 d.sin6_addr = origdst; 2047 ia = (struct in6_ifaddr *) 2048 ifa_ifwithaddr((struct sockaddr *)&d); 2049 if (ia && 2050 !(ia->ia6_flags & 2051 (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY))) { 2052 src = &ia->ia_addr.sin6_addr; 2053 } 2054 } 2055 } 2056 2057 if (src == NULL) { 2058 int e; 2059 struct sockaddr_in6 sin6; 2060 struct route_in6 ro; 2061 2062 /* 2063 * This case matches to multicasts, our anycast, or unicasts 2064 * that we do not own. Select a source address based on the 2065 * source address of the erroneous packet. 2066 */ 2067 bzero(&sin6, sizeof(sin6)); 2068 sin6.sin6_family = AF_INET6; 2069 sin6.sin6_len = sizeof(sin6); 2070 sin6.sin6_addr = ip6->ip6_dst; /* zone ID should be embedded */ 2071 2072 bzero(&ro, sizeof(ro)); 2073 src = in6_selectsrc(&sin6, NULL, NULL, &ro, NULL, &outif, &e); 2074 if (ro.ro_rt) { /* XXX: see comments in icmp6_mtudisc_update */ 2075 RTFREE(ro.ro_rt); /* XXX: we could use this */ 2076 } 2077 if (src == NULL) { 2078 nd6log((LOG_DEBUG, 2079 "icmp6_reflect: source can't be determined: " 2080 "dst=%s, error=%d\n", 2081 ip6_sprintf(&sin6.sin6_addr), e)); 2082 goto bad; 2083 } 2084 } 2085 2086 ip6->ip6_src = *src; 2087 ip6->ip6_flow = 0; 2088 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2089 ip6->ip6_vfc |= IPV6_VERSION; 2090 ip6->ip6_nxt = IPPROTO_ICMPV6; 2091 if (m->m_pkthdr.rcvif) { 2092 /* XXX: This may not be the outgoing interface */ 2093 ip6->ip6_hlim = ND_IFINFO(m->m_pkthdr.rcvif)->chlim; 2094 } else 2095 ip6->ip6_hlim = ip6_defhlim; 2096 2097 m->m_pkthdr.csum_flags = 0; 2098 icmp6->icmp6_cksum = 0; 2099 icmp6->icmp6_cksum = in6_cksum(m, IPPROTO_ICMPV6, 2100 sizeof(struct ip6_hdr), plen); 2101 2102 /* 2103 * XXX option handling 2104 */ 2105 2106 m->m_flags &= ~(M_BCAST|M_MCAST); 2107 2108 /* 2109 * To avoid a "too big" situation at an intermediate router 2110 * and the path MTU discovery process, specify the IPV6_MINMTU flag. 2111 * Note that only echo and node information replies are affected, 2112 * since the length of ICMP6 errors is limited to the minimum MTU. 2113 */ 2114 if (ip6_output(m, NULL, NULL, IPV6_MINMTU, NULL, NULL, &outif) != 0 && 2115 outif) 2116 icmp6_ifstat_inc(outif, ifs6_out_error); 2117 2118 if (outif) 2119 icmp6_ifoutstat_inc(outif, type, code); 2120 2121 return; 2122 2123 bad: 2124 m_freem(m); 2125 return; 2126 } 2127 2128 static const char * 2129 icmp6_redirect_diag(src6, dst6, tgt6) 2130 struct in6_addr *src6; 2131 struct in6_addr *dst6; 2132 struct in6_addr *tgt6; 2133 { 2134 static char buf[1024]; 2135 snprintf(buf, sizeof(buf), "(src=%s dst=%s tgt=%s)", 2136 ip6_sprintf(src6), ip6_sprintf(dst6), ip6_sprintf(tgt6)); 2137 return buf; 2138 } 2139 2140 void 2141 icmp6_redirect_input(m, off) 2142 struct mbuf *m; 2143 int off; 2144 { 2145 struct ifnet *ifp = m->m_pkthdr.rcvif; 2146 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 2147 struct nd_redirect *nd_rd; 2148 int icmp6len = ntohs(ip6->ip6_plen); 2149 char *lladdr = NULL; 2150 int lladdrlen = 0; 2151 struct rtentry *rt = NULL; 2152 int is_router; 2153 int is_onlink; 2154 struct in6_addr src6 = ip6->ip6_src; 2155 struct in6_addr redtgt6; 2156 struct in6_addr reddst6; 2157 union nd_opts ndopts; 2158 2159 if (!ifp) 2160 return; 2161 2162 /* XXX if we are router, we don't update route by icmp6 redirect */ 2163 if (ip6_forwarding) 2164 goto freeit; 2165 if (!icmp6_rediraccept) 2166 goto freeit; 2167 2168 IP6_EXTHDR_GET(nd_rd, struct nd_redirect *, m, off, icmp6len); 2169 if (nd_rd == NULL) { 2170 icmp6stat.icp6s_tooshort++; 2171 return; 2172 } 2173 redtgt6 = nd_rd->nd_rd_target; 2174 reddst6 = nd_rd->nd_rd_dst; 2175 2176 if (in6_setscope(&redtgt6, m->m_pkthdr.rcvif, NULL) || 2177 in6_setscope(&reddst6, m->m_pkthdr.rcvif, NULL)) { 2178 goto freeit; 2179 } 2180 2181 /* validation */ 2182 if (!IN6_IS_ADDR_LINKLOCAL(&src6)) { 2183 nd6log((LOG_ERR, 2184 "ICMP6 redirect sent from %s rejected; " 2185 "must be from linklocal\n", ip6_sprintf(&src6))); 2186 goto bad; 2187 } 2188 if (ip6->ip6_hlim != 255) { 2189 nd6log((LOG_ERR, 2190 "ICMP6 redirect sent from %s rejected; " 2191 "hlim=%d (must be 255)\n", 2192 ip6_sprintf(&src6), ip6->ip6_hlim)); 2193 goto bad; 2194 } 2195 { 2196 /* ip6->ip6_src must be equal to gw for icmp6->icmp6_reddst */ 2197 struct sockaddr_in6 sin6; 2198 struct in6_addr *gw6; 2199 2200 bzero(&sin6, sizeof(sin6)); 2201 sin6.sin6_family = AF_INET6; 2202 sin6.sin6_len = sizeof(struct sockaddr_in6); 2203 bcopy(&reddst6, &sin6.sin6_addr, sizeof(reddst6)); 2204 rt = rtalloc1((struct sockaddr *)&sin6, 0); 2205 if (rt) { 2206 if (rt->rt_gateway == NULL || 2207 rt->rt_gateway->sa_family != AF_INET6) { 2208 nd6log((LOG_ERR, 2209 "ICMP6 redirect rejected; no route " 2210 "with inet6 gateway found for redirect dst: %s\n", 2211 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2212 RTFREE(rt); 2213 goto bad; 2214 } 2215 2216 gw6 = &(((struct sockaddr_in6 *)rt->rt_gateway)->sin6_addr); 2217 if (bcmp(&src6, gw6, sizeof(struct in6_addr)) != 0) { 2218 nd6log((LOG_ERR, 2219 "ICMP6 redirect rejected; " 2220 "not equal to gw-for-src=%s (must be same): " 2221 "%s\n", 2222 ip6_sprintf(gw6), 2223 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2224 RTFREE(rt); 2225 goto bad; 2226 } 2227 } else { 2228 nd6log((LOG_ERR, 2229 "ICMP6 redirect rejected; " 2230 "no route found for redirect dst: %s\n", 2231 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2232 goto bad; 2233 } 2234 RTFREE(rt); 2235 rt = NULL; 2236 } 2237 if (IN6_IS_ADDR_MULTICAST(&reddst6)) { 2238 nd6log((LOG_ERR, 2239 "ICMP6 redirect rejected; " 2240 "redirect dst must be unicast: %s\n", 2241 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2242 goto bad; 2243 } 2244 2245 is_router = is_onlink = 0; 2246 if (IN6_IS_ADDR_LINKLOCAL(&redtgt6)) 2247 is_router = 1; /* router case */ 2248 if (bcmp(&redtgt6, &reddst6, sizeof(redtgt6)) == 0) 2249 is_onlink = 1; /* on-link destination case */ 2250 if (!is_router && !is_onlink) { 2251 nd6log((LOG_ERR, 2252 "ICMP6 redirect rejected; " 2253 "neither router case nor onlink case: %s\n", 2254 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2255 goto bad; 2256 } 2257 /* validation passed */ 2258 2259 icmp6len -= sizeof(*nd_rd); 2260 nd6_option_init(nd_rd + 1, icmp6len, &ndopts); 2261 if (nd6_options(&ndopts) < 0) { 2262 nd6log((LOG_INFO, "icmp6_redirect_input: " 2263 "invalid ND option, rejected: %s\n", 2264 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2265 /* nd6_options have incremented stats */ 2266 goto freeit; 2267 } 2268 2269 if (ndopts.nd_opts_tgt_lladdr) { 2270 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 2271 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 2272 } 2273 2274 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 2275 nd6log((LOG_INFO, 2276 "icmp6_redirect_input: lladdrlen mismatch for %s " 2277 "(if %d, icmp6 packet %d): %s\n", 2278 ip6_sprintf(&redtgt6), ifp->if_addrlen, lladdrlen - 2, 2279 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2280 goto bad; 2281 } 2282 2283 /* RFC 2461 8.3 */ 2284 nd6_cache_lladdr(ifp, &redtgt6, lladdr, lladdrlen, ND_REDIRECT, 2285 is_onlink ? ND_REDIRECT_ONLINK : ND_REDIRECT_ROUTER); 2286 2287 if (!is_onlink) { /* better router case. perform rtredirect. */ 2288 /* perform rtredirect */ 2289 struct sockaddr_in6 sdst; 2290 struct sockaddr_in6 sgw; 2291 struct sockaddr_in6 ssrc; 2292 unsigned long rtcount; 2293 struct rtentry *newrt = NULL; 2294 2295 /* 2296 * do not install redirect route, if the number of entries 2297 * is too much (> hiwat). note that, the node (= host) will 2298 * work just fine even if we do not install redirect route 2299 * (there will be additional hops, though). 2300 */ 2301 rtcount = rt_timer_count(icmp6_redirect_timeout_q); 2302 if (0 <= icmp6_redirect_hiwat && rtcount > icmp6_redirect_hiwat) 2303 return; 2304 else if (0 <= icmp6_redirect_lowat && 2305 rtcount > icmp6_redirect_lowat) { 2306 /* 2307 * XXX nuke a victim, install the new one. 2308 */ 2309 } 2310 2311 bzero(&sdst, sizeof(sdst)); 2312 bzero(&sgw, sizeof(sgw)); 2313 bzero(&ssrc, sizeof(ssrc)); 2314 sdst.sin6_family = sgw.sin6_family = ssrc.sin6_family = AF_INET6; 2315 sdst.sin6_len = sgw.sin6_len = ssrc.sin6_len = 2316 sizeof(struct sockaddr_in6); 2317 bcopy(&redtgt6, &sgw.sin6_addr, sizeof(struct in6_addr)); 2318 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2319 bcopy(&src6, &ssrc.sin6_addr, sizeof(struct in6_addr)); 2320 rtredirect((struct sockaddr *)&sdst, (struct sockaddr *)&sgw, 2321 (struct sockaddr *)NULL, RTF_GATEWAY | RTF_HOST, 2322 (struct sockaddr *)&ssrc, 2323 &newrt); 2324 2325 if (newrt) { 2326 (void)rt_timer_add(newrt, icmp6_redirect_timeout, 2327 icmp6_redirect_timeout_q); 2328 rtfree(newrt); 2329 } 2330 } 2331 /* finally update cached route in each socket via pfctlinput */ 2332 { 2333 struct sockaddr_in6 sdst; 2334 2335 bzero(&sdst, sizeof(sdst)); 2336 sdst.sin6_family = AF_INET6; 2337 sdst.sin6_len = sizeof(struct sockaddr_in6); 2338 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2339 pfctlinput(PRC_REDIRECT_HOST, (struct sockaddr *)&sdst); 2340 #ifdef IPSEC 2341 key_sa_routechange((struct sockaddr *)&sdst); 2342 #endif 2343 } 2344 2345 freeit: 2346 m_freem(m); 2347 return; 2348 2349 bad: 2350 icmp6stat.icp6s_badredirect++; 2351 m_freem(m); 2352 } 2353 2354 void 2355 icmp6_redirect_output(m0, rt) 2356 struct mbuf *m0; 2357 struct rtentry *rt; 2358 { 2359 struct ifnet *ifp; /* my outgoing interface */ 2360 struct in6_addr *ifp_ll6; 2361 struct in6_addr *nexthop; 2362 struct ip6_hdr *sip6; /* m0 as struct ip6_hdr */ 2363 struct mbuf *m = NULL; /* newly allocated one */ 2364 struct ip6_hdr *ip6; /* m as struct ip6_hdr */ 2365 struct nd_redirect *nd_rd; 2366 size_t maxlen; 2367 u_char *p; 2368 struct sockaddr_in6 src_sa; 2369 2370 icmp6_errcount(&icmp6stat.icp6s_outerrhist, ND_REDIRECT, 0); 2371 2372 /* if we are not router, we don't send icmp6 redirect */ 2373 if (!ip6_forwarding) 2374 goto fail; 2375 2376 /* sanity check */ 2377 if (!m0 || !rt || !(rt->rt_flags & RTF_UP) || !(ifp = rt->rt_ifp)) 2378 goto fail; 2379 2380 /* 2381 * Address check: 2382 * the source address must identify a neighbor, and 2383 * the destination address must not be a multicast address 2384 * [RFC 2461, sec 8.2] 2385 */ 2386 sip6 = mtod(m0, struct ip6_hdr *); 2387 bzero(&src_sa, sizeof(src_sa)); 2388 src_sa.sin6_family = AF_INET6; 2389 src_sa.sin6_len = sizeof(src_sa); 2390 src_sa.sin6_addr = sip6->ip6_src; 2391 if (nd6_is_addr_neighbor(&src_sa, ifp) == 0) 2392 goto fail; 2393 if (IN6_IS_ADDR_MULTICAST(&sip6->ip6_dst)) 2394 goto fail; /* what should we do here? */ 2395 2396 /* rate limit */ 2397 if (icmp6_ratelimit(&sip6->ip6_src, ND_REDIRECT, 0)) 2398 goto fail; 2399 2400 /* 2401 * Since we are going to append up to 1280 bytes (= IPV6_MMTU), 2402 * we almost always ask for an mbuf cluster for simplicity. 2403 * (MHLEN < IPV6_MMTU is almost always true) 2404 */ 2405 #if IPV6_MMTU >= MCLBYTES 2406 # error assumption failed about IPV6_MMTU and MCLBYTES 2407 #endif 2408 MGETHDR(m, M_DONTWAIT, MT_HEADER); 2409 if (m && IPV6_MMTU >= MHLEN) 2410 MCLGET(m, M_DONTWAIT); 2411 if (!m) 2412 goto fail; 2413 m->m_pkthdr.rcvif = NULL; 2414 m->m_len = 0; 2415 maxlen = M_TRAILINGSPACE(m); 2416 maxlen = min(IPV6_MMTU, maxlen); 2417 /* just for safety */ 2418 if (maxlen < sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) + 2419 ((sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7)) { 2420 goto fail; 2421 } 2422 2423 { 2424 /* get ip6 linklocal address for ifp(my outgoing interface). */ 2425 struct in6_ifaddr *ia; 2426 if ((ia = in6ifa_ifpforlinklocal(ifp, 2427 IN6_IFF_NOTREADY| 2428 IN6_IFF_ANYCAST)) == NULL) 2429 goto fail; 2430 ifp_ll6 = &ia->ia_addr.sin6_addr; 2431 } 2432 2433 /* get ip6 linklocal address for the router. */ 2434 if (rt->rt_gateway && (rt->rt_flags & RTF_GATEWAY)) { 2435 struct sockaddr_in6 *sin6; 2436 sin6 = (struct sockaddr_in6 *)rt->rt_gateway; 2437 nexthop = &sin6->sin6_addr; 2438 if (!IN6_IS_ADDR_LINKLOCAL(nexthop)) 2439 nexthop = NULL; 2440 } else 2441 nexthop = NULL; 2442 2443 /* ip6 */ 2444 ip6 = mtod(m, struct ip6_hdr *); 2445 ip6->ip6_flow = 0; 2446 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2447 ip6->ip6_vfc |= IPV6_VERSION; 2448 /* ip6->ip6_plen will be set later */ 2449 ip6->ip6_nxt = IPPROTO_ICMPV6; 2450 ip6->ip6_hlim = 255; 2451 /* ip6->ip6_src must be linklocal addr for my outgoing if. */ 2452 bcopy(ifp_ll6, &ip6->ip6_src, sizeof(struct in6_addr)); 2453 bcopy(&sip6->ip6_src, &ip6->ip6_dst, sizeof(struct in6_addr)); 2454 2455 /* ND Redirect */ 2456 nd_rd = (struct nd_redirect *)(ip6 + 1); 2457 nd_rd->nd_rd_type = ND_REDIRECT; 2458 nd_rd->nd_rd_code = 0; 2459 nd_rd->nd_rd_reserved = 0; 2460 if (rt->rt_flags & RTF_GATEWAY) { 2461 /* 2462 * nd_rd->nd_rd_target must be a link-local address in 2463 * better router cases. 2464 */ 2465 if (!nexthop) 2466 goto fail; 2467 bcopy(nexthop, &nd_rd->nd_rd_target, 2468 sizeof(nd_rd->nd_rd_target)); 2469 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2470 sizeof(nd_rd->nd_rd_dst)); 2471 } else { 2472 /* make sure redtgt == reddst */ 2473 nexthop = &sip6->ip6_dst; 2474 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_target, 2475 sizeof(nd_rd->nd_rd_target)); 2476 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2477 sizeof(nd_rd->nd_rd_dst)); 2478 } 2479 2480 p = (u_char *)(nd_rd + 1); 2481 2482 { 2483 /* target lladdr option */ 2484 struct rtentry *rt_nexthop = NULL; 2485 int len; 2486 struct sockaddr_dl *sdl; 2487 struct nd_opt_hdr *nd_opt; 2488 char *lladdr; 2489 2490 rt_nexthop = nd6_lookup(nexthop, 0, ifp); 2491 if (!rt_nexthop) 2492 goto nolladdropt; 2493 len = sizeof(*nd_opt) + ifp->if_addrlen; 2494 len = (len + 7) & ~7; /* round by 8 */ 2495 /* safety check */ 2496 if (len + (p - (u_char *)ip6) > maxlen) 2497 goto nolladdropt; 2498 if (!(rt_nexthop->rt_flags & RTF_GATEWAY) && 2499 (rt_nexthop->rt_flags & RTF_LLINFO) && 2500 (rt_nexthop->rt_gateway->sa_family == AF_LINK) && 2501 (sdl = (struct sockaddr_dl *)rt_nexthop->rt_gateway) && 2502 sdl->sdl_alen) { 2503 nd_opt = (struct nd_opt_hdr *)p; 2504 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 2505 nd_opt->nd_opt_len = len >> 3; 2506 lladdr = (char *)(nd_opt + 1); 2507 bcopy(LLADDR(sdl), lladdr, ifp->if_addrlen); 2508 p += len; 2509 } 2510 } 2511 nolladdropt:; 2512 2513 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2514 2515 /* just to be safe */ 2516 if (m0->m_flags & M_DECRYPTED) 2517 goto noredhdropt; 2518 if (p - (u_char *)ip6 > maxlen) 2519 goto noredhdropt; 2520 2521 { 2522 /* redirected header option */ 2523 int len; 2524 struct nd_opt_rd_hdr *nd_opt_rh; 2525 2526 /* 2527 * compute the maximum size for icmp6 redirect header option. 2528 * XXX room for auth header? 2529 */ 2530 len = maxlen - (p - (u_char *)ip6); 2531 len &= ~7; 2532 2533 /* 2534 * Redirected header option spec (RFC2461 4.6.3) talks nothing 2535 * about padding/truncate rule for the original IP packet. 2536 * From the discussion on IPv6imp in Feb 1999, 2537 * the consensus was: 2538 * - "attach as much as possible" is the goal 2539 * - pad if not aligned (original size can be guessed by 2540 * original ip6 header) 2541 * Following code adds the padding if it is simple enough, 2542 * and truncates if not. 2543 */ 2544 if (len - sizeof(*nd_opt_rh) < m0->m_pkthdr.len) { 2545 /* not enough room, truncate */ 2546 m_adj(m0, (len - sizeof(*nd_opt_rh)) - 2547 m0->m_pkthdr.len); 2548 } else { 2549 /* 2550 * enough room, truncate if not aligned. 2551 * we don't pad here for simplicity. 2552 */ 2553 size_t extra; 2554 2555 extra = m0->m_pkthdr.len % 8; 2556 if (extra) { 2557 /* truncate */ 2558 m_adj(m0, -extra); 2559 } 2560 len = m0->m_pkthdr.len + sizeof(*nd_opt_rh); 2561 } 2562 2563 nd_opt_rh = (struct nd_opt_rd_hdr *)p; 2564 bzero(nd_opt_rh, sizeof(*nd_opt_rh)); 2565 nd_opt_rh->nd_opt_rh_type = ND_OPT_REDIRECTED_HEADER; 2566 nd_opt_rh->nd_opt_rh_len = len >> 3; 2567 p += sizeof(*nd_opt_rh); 2568 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2569 2570 /* connect m0 to m */ 2571 m->m_pkthdr.len += m0->m_pkthdr.len; 2572 m_cat(m, m0); 2573 m0 = NULL; 2574 } 2575 noredhdropt: 2576 if (m0) { 2577 m_freem(m0); 2578 m0 = NULL; 2579 } 2580 2581 /* XXX: clear embedded link IDs in the inner header */ 2582 in6_clearscope(&sip6->ip6_src); 2583 in6_clearscope(&sip6->ip6_dst); 2584 in6_clearscope(&nd_rd->nd_rd_target); 2585 in6_clearscope(&nd_rd->nd_rd_dst); 2586 2587 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr)); 2588 2589 nd_rd->nd_rd_cksum = 0; 2590 nd_rd->nd_rd_cksum 2591 = in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), ntohs(ip6->ip6_plen)); 2592 2593 /* send the packet to outside... */ 2594 if (ip6_output(m, NULL, NULL, 0, 2595 (struct ip6_moptions *)NULL, (struct socket *)NULL, NULL) != 0) 2596 icmp6_ifstat_inc(ifp, ifs6_out_error); 2597 2598 icmp6_ifstat_inc(ifp, ifs6_out_msg); 2599 icmp6_ifstat_inc(ifp, ifs6_out_redirect); 2600 icmp6stat.icp6s_outhist[ND_REDIRECT]++; 2601 2602 return; 2603 2604 fail: 2605 if (m) 2606 m_freem(m); 2607 if (m0) 2608 m_freem(m0); 2609 } 2610 2611 /* 2612 * ICMPv6 socket option processing. 2613 */ 2614 int 2615 icmp6_ctloutput(op, so, level, optname, mp) 2616 int op; 2617 struct socket *so; 2618 int level, optname; 2619 struct mbuf **mp; 2620 { 2621 int error = 0; 2622 int optlen; 2623 struct in6pcb *in6p = sotoin6pcb(so); 2624 struct mbuf *m = *mp; 2625 2626 optlen = m ? m->m_len : 0; 2627 2628 if (level != IPPROTO_ICMPV6) { 2629 if (op == PRCO_SETOPT && m) 2630 (void)m_free(m); 2631 return EINVAL; 2632 } 2633 2634 switch (op) { 2635 case PRCO_SETOPT: 2636 switch (optname) { 2637 case ICMP6_FILTER: 2638 { 2639 struct icmp6_filter *p; 2640 2641 if (optlen != sizeof(*p)) { 2642 error = EMSGSIZE; 2643 break; 2644 } 2645 p = mtod(m, struct icmp6_filter *); 2646 if (!p || !in6p->in6p_icmp6filt) { 2647 error = EINVAL; 2648 break; 2649 } 2650 bcopy(p, in6p->in6p_icmp6filt, 2651 sizeof(struct icmp6_filter)); 2652 error = 0; 2653 break; 2654 } 2655 2656 default: 2657 error = ENOPROTOOPT; 2658 break; 2659 } 2660 if (m) 2661 (void)m_freem(m); 2662 break; 2663 2664 case PRCO_GETOPT: 2665 switch (optname) { 2666 case ICMP6_FILTER: 2667 { 2668 struct icmp6_filter *p; 2669 2670 if (!in6p->in6p_icmp6filt) { 2671 error = EINVAL; 2672 break; 2673 } 2674 *mp = m = m_get(M_WAIT, MT_SOOPTS); 2675 m->m_len = sizeof(struct icmp6_filter); 2676 p = mtod(m, struct icmp6_filter *); 2677 bcopy(in6p->in6p_icmp6filt, p, 2678 sizeof(struct icmp6_filter)); 2679 error = 0; 2680 break; 2681 } 2682 2683 default: 2684 error = ENOPROTOOPT; 2685 break; 2686 } 2687 break; 2688 } 2689 2690 return (error); 2691 } 2692 2693 /* 2694 * Perform rate limit check. 2695 * Returns 0 if it is okay to send the icmp6 packet. 2696 * Returns 1 if the router SHOULD NOT send this icmp6 packet due to rate 2697 * limitation. 2698 * 2699 * XXX per-destination/type check necessary? 2700 */ 2701 static int 2702 icmp6_ratelimit(dst, type, code) 2703 const struct in6_addr *dst; /* not used at this moment */ 2704 const int type; /* not used at this moment */ 2705 const int code; /* not used at this moment */ 2706 { 2707 int ret; 2708 2709 ret = 0; /* okay to send */ 2710 2711 /* PPS limit */ 2712 if (!ppsratecheck(&icmp6errppslim_last, &icmp6errpps_count, 2713 icmp6errppslim)) { 2714 /* The packet is subject to rate limit */ 2715 ret++; 2716 } 2717 2718 return ret; 2719 } 2720 2721 static struct rtentry * 2722 icmp6_mtudisc_clone(dst) 2723 struct sockaddr *dst; 2724 { 2725 struct rtentry *rt; 2726 int error; 2727 2728 rt = rtalloc1(dst, 1); 2729 if (rt == 0) 2730 return NULL; 2731 2732 /* If we didn't get a host route, allocate one */ 2733 if ((rt->rt_flags & RTF_HOST) == 0) { 2734 struct rtentry *nrt; 2735 2736 error = rtrequest((int) RTM_ADD, dst, 2737 (struct sockaddr *) rt->rt_gateway, 2738 (struct sockaddr *) 0, 2739 RTF_GATEWAY | RTF_HOST | RTF_DYNAMIC, &nrt); 2740 if (error) { 2741 rtfree(rt); 2742 return NULL; 2743 } 2744 nrt->rt_rmx = rt->rt_rmx; 2745 rtfree(rt); 2746 rt = nrt; 2747 } 2748 error = rt_timer_add(rt, icmp6_mtudisc_timeout, 2749 icmp6_mtudisc_timeout_q); 2750 if (error) { 2751 rtfree(rt); 2752 return NULL; 2753 } 2754 2755 return rt; /* caller need to call rtfree() */ 2756 } 2757 2758 static void 2759 icmp6_mtudisc_timeout(rt, r) 2760 struct rtentry *rt; 2761 struct rttimer *r; 2762 { 2763 if (rt == NULL) 2764 panic("icmp6_mtudisc_timeout: bad route to timeout"); 2765 if ((rt->rt_flags & (RTF_DYNAMIC | RTF_HOST)) == 2766 (RTF_DYNAMIC | RTF_HOST)) { 2767 rtrequest((int) RTM_DELETE, (struct sockaddr *)rt_key(rt), 2768 rt->rt_gateway, rt_mask(rt), rt->rt_flags, 0); 2769 } else { 2770 if (!(rt->rt_rmx.rmx_locks & RTV_MTU)) 2771 rt->rt_rmx.rmx_mtu = 0; 2772 } 2773 } 2774 2775 static void 2776 icmp6_redirect_timeout(rt, r) 2777 struct rtentry *rt; 2778 struct rttimer *r; 2779 { 2780 if (rt == NULL) 2781 panic("icmp6_redirect_timeout: bad route to timeout"); 2782 if ((rt->rt_flags & (RTF_GATEWAY | RTF_DYNAMIC | RTF_HOST)) == 2783 (RTF_GATEWAY | RTF_DYNAMIC | RTF_HOST)) { 2784 rtrequest((int) RTM_DELETE, (struct sockaddr *)rt_key(rt), 2785 rt->rt_gateway, rt_mask(rt), rt->rt_flags, 0); 2786 } 2787 } 2788 2789 /* 2790 * sysctl helper routine for the net.inet6.icmp6.nd6 nodes. silly? 2791 */ 2792 static int 2793 sysctl_net_inet6_icmp6_nd6(SYSCTLFN_ARGS) 2794 { 2795 2796 if (namelen != 0) 2797 return (EINVAL); 2798 2799 return (nd6_sysctl(rnode->sysctl_num, oldp, oldlenp, 2800 /*XXXUNCONST*/ 2801 __UNCONST(newp), newlen)); 2802 } 2803 2804 SYSCTL_SETUP(sysctl_net_inet6_icmp6_setup, 2805 "sysctl net.inet6.icmp6 subtree setup") 2806 { 2807 extern int nd6_maxqueuelen; /* defined in nd6.c */ 2808 2809 sysctl_createv(clog, 0, NULL, NULL, 2810 CTLFLAG_PERMANENT, 2811 CTLTYPE_NODE, "net", NULL, 2812 NULL, 0, NULL, 0, 2813 CTL_NET, CTL_EOL); 2814 sysctl_createv(clog, 0, NULL, NULL, 2815 CTLFLAG_PERMANENT, 2816 CTLTYPE_NODE, "inet6", NULL, 2817 NULL, 0, NULL, 0, 2818 CTL_NET, PF_INET6, CTL_EOL); 2819 sysctl_createv(clog, 0, NULL, NULL, 2820 CTLFLAG_PERMANENT, 2821 CTLTYPE_NODE, "icmp6", 2822 SYSCTL_DESCR("ICMPv6 related settings"), 2823 NULL, 0, NULL, 0, 2824 CTL_NET, PF_INET6, IPPROTO_ICMPV6, CTL_EOL); 2825 2826 sysctl_createv(clog, 0, NULL, NULL, 2827 CTLFLAG_PERMANENT, 2828 CTLTYPE_STRUCT, "stats", 2829 SYSCTL_DESCR("ICMPv6 transmission statistics"), 2830 NULL, 0, &icmp6stat, sizeof(icmp6stat), 2831 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2832 ICMPV6CTL_STATS, CTL_EOL); 2833 sysctl_createv(clog, 0, NULL, NULL, 2834 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2835 CTLTYPE_INT, "rediraccept", 2836 SYSCTL_DESCR("Accept and process redirect messages"), 2837 NULL, 0, &icmp6_rediraccept, 0, 2838 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2839 ICMPV6CTL_REDIRACCEPT, CTL_EOL); 2840 sysctl_createv(clog, 0, NULL, NULL, 2841 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2842 CTLTYPE_INT, "redirtimeout", 2843 SYSCTL_DESCR("Redirect generated route lifetime"), 2844 NULL, 0, &icmp6_redirtimeout, 0, 2845 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2846 ICMPV6CTL_REDIRTIMEOUT, CTL_EOL); 2847 #if 0 /* obsoleted */ 2848 sysctl_createv(clog, 0, NULL, NULL, 2849 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2850 CTLTYPE_INT, "errratelimit", NULL, 2851 NULL, 0, &icmp6_errratelimit, 0, 2852 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2853 ICMPV6CTL_ERRRATELIMIT, CTL_EOL); 2854 #endif 2855 sysctl_createv(clog, 0, NULL, NULL, 2856 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2857 CTLTYPE_INT, "nd6_prune", 2858 SYSCTL_DESCR("Neighbor discovery prune interval"), 2859 NULL, 0, &nd6_prune, 0, 2860 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2861 ICMPV6CTL_ND6_PRUNE, CTL_EOL); 2862 sysctl_createv(clog, 0, NULL, NULL, 2863 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2864 CTLTYPE_INT, "nd6_delay", 2865 SYSCTL_DESCR("First probe delay time"), 2866 NULL, 0, &nd6_delay, 0, 2867 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2868 ICMPV6CTL_ND6_DELAY, CTL_EOL); 2869 sysctl_createv(clog, 0, NULL, NULL, 2870 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2871 CTLTYPE_INT, "nd6_umaxtries", 2872 SYSCTL_DESCR("Number of unicast discovery attempts"), 2873 NULL, 0, &nd6_umaxtries, 0, 2874 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2875 ICMPV6CTL_ND6_UMAXTRIES, CTL_EOL); 2876 sysctl_createv(clog, 0, NULL, NULL, 2877 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2878 CTLTYPE_INT, "nd6_mmaxtries", 2879 SYSCTL_DESCR("Number of multicast discovery attempts"), 2880 NULL, 0, &nd6_mmaxtries, 0, 2881 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2882 ICMPV6CTL_ND6_MMAXTRIES, CTL_EOL); 2883 sysctl_createv(clog, 0, NULL, NULL, 2884 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2885 CTLTYPE_INT, "nd6_useloopback", 2886 SYSCTL_DESCR("Use loopback interface for local traffic"), 2887 NULL, 0, &nd6_useloopback, 0, 2888 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2889 ICMPV6CTL_ND6_USELOOPBACK, CTL_EOL); 2890 #if 0 /* obsoleted */ 2891 sysctl_createv(clog, 0, NULL, NULL, 2892 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2893 CTLTYPE_INT, "nd6_proxyall", NULL, 2894 NULL, 0, &nd6_proxyall, 0, 2895 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2896 ICMPV6CTL_ND6_PROXYALL, CTL_EOL); 2897 #endif 2898 sysctl_createv(clog, 0, NULL, NULL, 2899 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2900 CTLTYPE_INT, "nodeinfo", 2901 SYSCTL_DESCR("Respond to node information requests"), 2902 NULL, 0, &icmp6_nodeinfo, 0, 2903 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2904 ICMPV6CTL_NODEINFO, CTL_EOL); 2905 sysctl_createv(clog, 0, NULL, NULL, 2906 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2907 CTLTYPE_INT, "errppslimit", 2908 SYSCTL_DESCR("Maximum ICMP errors sent per second"), 2909 NULL, 0, &icmp6errppslim, 0, 2910 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2911 ICMPV6CTL_ERRPPSLIMIT, CTL_EOL); 2912 sysctl_createv(clog, 0, NULL, NULL, 2913 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2914 CTLTYPE_INT, "nd6_maxnudhint", 2915 SYSCTL_DESCR("Maximum neighbor unreachable hint count"), 2916 NULL, 0, &nd6_maxnudhint, 0, 2917 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2918 ICMPV6CTL_ND6_MAXNUDHINT, CTL_EOL); 2919 sysctl_createv(clog, 0, NULL, NULL, 2920 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2921 CTLTYPE_INT, "mtudisc_hiwat", 2922 SYSCTL_DESCR("Low mark on MTU Discovery route timers"), 2923 NULL, 0, &icmp6_mtudisc_hiwat, 0, 2924 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2925 ICMPV6CTL_MTUDISC_HIWAT, CTL_EOL); 2926 sysctl_createv(clog, 0, NULL, NULL, 2927 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2928 CTLTYPE_INT, "mtudisc_lowat", 2929 SYSCTL_DESCR("Low mark on MTU Discovery route timers"), 2930 NULL, 0, &icmp6_mtudisc_lowat, 0, 2931 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2932 ICMPV6CTL_MTUDISC_LOWAT, CTL_EOL); 2933 sysctl_createv(clog, 0, NULL, NULL, 2934 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2935 CTLTYPE_INT, "nd6_debug", 2936 SYSCTL_DESCR("Enable neighbor discovery debug output"), 2937 NULL, 0, &nd6_debug, 0, 2938 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2939 ICMPV6CTL_ND6_DEBUG, CTL_EOL); 2940 sysctl_createv(clog, 0, NULL, NULL, 2941 CTLFLAG_PERMANENT, 2942 CTLTYPE_STRUCT, "nd6_drlist", 2943 SYSCTL_DESCR("Default router list"), 2944 sysctl_net_inet6_icmp6_nd6, 0, NULL, 0, 2945 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2946 ICMPV6CTL_ND6_DRLIST, CTL_EOL); 2947 sysctl_createv(clog, 0, NULL, NULL, 2948 CTLFLAG_PERMANENT, 2949 CTLTYPE_STRUCT, "nd6_prlist", 2950 SYSCTL_DESCR("Prefix list"), 2951 sysctl_net_inet6_icmp6_nd6, 0, NULL, 0, 2952 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2953 ICMPV6CTL_ND6_PRLIST, CTL_EOL); 2954 sysctl_createv(clog, 0, NULL, NULL, 2955 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2956 CTLTYPE_INT, "maxqueuelen", 2957 SYSCTL_DESCR("max packet queue len for a unresolved ND"), 2958 NULL, 1, &nd6_maxqueuelen, 0, 2959 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2960 ICMPV6CTL_ND6_MAXQLEN, CTL_EOL); 2961 } 2962
Indexes created Sun Sep 28 12:09:53 GMT 2025