1 /* $NetBSD: icmp6.c,v 1.148 2008/05/07 11:28:37 bouyer 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 1.148 2008/05/07 11:28:37 bouyer 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 <netinet6/ip6_private.h> 93 #include <netinet/icmp6.h> 94 #include <netinet6/icmp6_private.h> 95 #include <netinet6/mld6_var.h> 96 #include <netinet6/in6_pcb.h> 97 #include <netinet6/nd6.h> 98 #include <netinet6/in6_ifattach.h> 99 #include <netinet6/ip6protosw.h> 100 #include <netinet6/scope6_var.h> 101 102 #ifdef IPSEC 103 #include <netinet6/ipsec.h> 104 #include <netkey/key.h> 105 #endif 106 107 #ifdef FAST_IPSEC 108 #include <netipsec/ipsec.h> 109 #include <netipsec/key.h> 110 #endif 111 112 113 #include "faith.h" 114 #if defined(NFAITH) && 0 < NFAITH 115 #include <net/if_faith.h> 116 #endif 117 118 #include <net/net_osdep.h> 119 120 extern struct domain inet6domain; 121 122 percpu_t *icmp6stat_percpu; 123 124 extern struct inpcbtable raw6cbtable; 125 extern int icmp6errppslim; 126 static int icmp6errpps_count = 0; 127 static struct timeval icmp6errppslim_last; 128 extern int icmp6_nodeinfo; 129 130 /* 131 * List of callbacks to notify when Path MTU changes are made. 132 */ 133 struct icmp6_mtudisc_callback { 134 LIST_ENTRY(icmp6_mtudisc_callback) mc_list; 135 void (*mc_func)(struct in6_addr *); 136 }; 137 138 LIST_HEAD(, icmp6_mtudisc_callback) icmp6_mtudisc_callbacks = 139 LIST_HEAD_INITIALIZER(&icmp6_mtudisc_callbacks); 140 141 static struct rttimer_queue *icmp6_mtudisc_timeout_q = NULL; 142 extern int pmtu_expire; 143 144 /* XXX do these values make any sense? */ 145 static int icmp6_mtudisc_hiwat = 1280; 146 static int icmp6_mtudisc_lowat = 256; 147 148 /* 149 * keep track of # of redirect routes. 150 */ 151 static struct rttimer_queue *icmp6_redirect_timeout_q = NULL; 152 153 /* XXX experimental, turned off */ 154 static int icmp6_redirect_hiwat = -1; 155 static int icmp6_redirect_lowat = -1; 156 157 static void icmp6_errcount(u_int, int, int); 158 static int icmp6_rip6_input(struct mbuf **, int); 159 static int icmp6_ratelimit(const struct in6_addr *, const int, const int); 160 static const char *icmp6_redirect_diag(struct in6_addr *, 161 struct in6_addr *, struct in6_addr *); 162 static struct mbuf *ni6_input(struct mbuf *, int); 163 static struct mbuf *ni6_nametodns(const char *, int, int); 164 static int ni6_dnsmatch(const char *, int, const char *, int); 165 static int ni6_addrs(struct icmp6_nodeinfo *, struct mbuf *, 166 struct ifnet **, char *); 167 static int ni6_store_addrs(struct icmp6_nodeinfo *, struct icmp6_nodeinfo *, 168 struct ifnet *, int); 169 static int icmp6_notify_error(struct mbuf *, int, int, int); 170 static struct rtentry *icmp6_mtudisc_clone(struct sockaddr *); 171 static void icmp6_mtudisc_timeout(struct rtentry *, struct rttimer *); 172 static void icmp6_redirect_timeout(struct rtentry *, struct rttimer *); 173 174 175 void 176 icmp6_init(void) 177 { 178 mld_init(); 179 icmp6_mtudisc_timeout_q = rt_timer_queue_create(pmtu_expire); 180 icmp6_redirect_timeout_q = rt_timer_queue_create(icmp6_redirtimeout); 181 182 icmp6stat_percpu = percpu_alloc(sizeof(uint64_t) * ICMP6_NSTATS); 183 } 184 185 static void 186 icmp6_errcount(u_int base, int type, int code) 187 { 188 switch (type) { 189 case ICMP6_DST_UNREACH: 190 switch (code) { 191 case ICMP6_DST_UNREACH_NOROUTE: 192 ICMP6_STATINC(base + ICMP6_ERRSTAT_DST_UNREACH_NOROUTE); 193 return; 194 case ICMP6_DST_UNREACH_ADMIN: 195 ICMP6_STATINC(base + ICMP6_ERRSTAT_DST_UNREACH_ADMIN); 196 return; 197 case ICMP6_DST_UNREACH_BEYONDSCOPE: 198 ICMP6_STATINC(base + 199 ICMP6_ERRSTAT_DST_UNREACH_BEYONDSCOPE); 200 return; 201 case ICMP6_DST_UNREACH_ADDR: 202 ICMP6_STATINC(base + ICMP6_ERRSTAT_DST_UNREACH_ADDR); 203 return; 204 case ICMP6_DST_UNREACH_NOPORT: 205 ICMP6_STATINC(base + ICMP6_ERRSTAT_DST_UNREACH_NOPORT); 206 return; 207 } 208 break; 209 case ICMP6_PACKET_TOO_BIG: 210 ICMP6_STATINC(base + ICMP6_ERRSTAT_PACKET_TOO_BIG); 211 return; 212 case ICMP6_TIME_EXCEEDED: 213 switch (code) { 214 case ICMP6_TIME_EXCEED_TRANSIT: 215 ICMP6_STATINC(base + ICMP6_ERRSTAT_TIME_EXCEED_TRANSIT); 216 return; 217 case ICMP6_TIME_EXCEED_REASSEMBLY: 218 ICMP6_STATINC(base + 219 ICMP6_ERRSTAT_TIME_EXCEED_REASSEMBLY); 220 return; 221 } 222 break; 223 case ICMP6_PARAM_PROB: 224 switch (code) { 225 case ICMP6_PARAMPROB_HEADER: 226 ICMP6_STATINC(base + ICMP6_ERRSTAT_PARAMPROB_HEADER); 227 return; 228 case ICMP6_PARAMPROB_NEXTHEADER: 229 ICMP6_STATINC(base + 230 ICMP6_ERRSTAT_PARAMPROB_NEXTHEADER); 231 return; 232 case ICMP6_PARAMPROB_OPTION: 233 ICMP6_STATINC(base + ICMP6_ERRSTAT_PARAMPROB_OPTION); 234 return; 235 } 236 break; 237 case ND_REDIRECT: 238 ICMP6_STATINC(base + ICMP6_ERRSTAT_REDIRECT); 239 return; 240 } 241 ICMP6_STATINC(base + ICMP6_ERRSTAT_UNKNOWN); 242 } 243 244 /* 245 * Register a Path MTU Discovery callback. 246 */ 247 void 248 icmp6_mtudisc_callback_register(void (*func)(struct in6_addr *)) 249 { 250 struct icmp6_mtudisc_callback *mc; 251 252 for (mc = LIST_FIRST(&icmp6_mtudisc_callbacks); mc != NULL; 253 mc = LIST_NEXT(mc, mc_list)) { 254 if (mc->mc_func == func) 255 return; 256 } 257 258 mc = malloc(sizeof(*mc), M_PCB, M_NOWAIT); 259 if (mc == NULL) 260 panic("icmp6_mtudisc_callback_register"); 261 262 mc->mc_func = func; 263 LIST_INSERT_HEAD(&icmp6_mtudisc_callbacks, mc, mc_list); 264 } 265 266 /* 267 * A wrapper function for icmp6_error() necessary when the erroneous packet 268 * may not contain enough scope zone information. 269 */ 270 void 271 icmp6_error2(struct mbuf *m, int type, int code, int param, 272 struct ifnet *ifp) 273 { 274 struct ip6_hdr *ip6; 275 276 if (ifp == NULL) 277 return; 278 279 if (m->m_len < sizeof(struct ip6_hdr)) { 280 m = m_pullup(m, sizeof(struct ip6_hdr)); 281 if (m == NULL) 282 return; 283 } 284 285 ip6 = mtod(m, struct ip6_hdr *); 286 287 if (in6_setscope(&ip6->ip6_src, ifp, NULL) != 0) 288 return; 289 if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0) 290 return; 291 292 icmp6_error(m, type, code, param); 293 } 294 295 /* 296 * Generate an error packet of type error in response to bad IP6 packet. 297 */ 298 void 299 icmp6_error(struct mbuf *m, int type, int code, int param) 300 { 301 struct ip6_hdr *oip6, *nip6; 302 struct icmp6_hdr *icmp6; 303 u_int preplen; 304 int off; 305 int nxt; 306 307 ICMP6_STATINC(ICMP6_STAT_ERROR); 308 309 /* count per-type-code statistics */ 310 icmp6_errcount(ICMP6_STAT_OUTERRHIST, type, code); 311 312 if (m->m_flags & M_DECRYPTED) { 313 ICMP6_STATINC(ICMP6_STAT_CANTERROR); 314 goto freeit; 315 } 316 317 if (M_UNWRITABLE(m, sizeof(struct ip6_hdr)) && 318 (m = m_pullup(m, sizeof(struct ip6_hdr))) == NULL) 319 return; 320 oip6 = mtod(m, struct ip6_hdr *); 321 322 /* 323 * If the destination address of the erroneous packet is a multicast 324 * address, or the packet was sent using link-layer multicast, 325 * we should basically suppress sending an error (RFC 2463, Section 326 * 2.4). 327 * We have two exceptions (the item e.2 in that section): 328 * - the Pakcet Too Big message can be sent for path MTU discovery. 329 * - the Parameter Problem Message that can be allowed an icmp6 error 330 * in the option type field. This check has been done in 331 * ip6_unknown_opt(), so we can just check the type and code. 332 */ 333 if ((m->m_flags & (M_BCAST|M_MCAST) || 334 IN6_IS_ADDR_MULTICAST(&oip6->ip6_dst)) && 335 (type != ICMP6_PACKET_TOO_BIG && 336 (type != ICMP6_PARAM_PROB || 337 code != ICMP6_PARAMPROB_OPTION))) 338 goto freeit; 339 340 /* 341 * RFC 2463, 2.4 (e.5): source address check. 342 * XXX: the case of anycast source? 343 */ 344 if (IN6_IS_ADDR_UNSPECIFIED(&oip6->ip6_src) || 345 IN6_IS_ADDR_MULTICAST(&oip6->ip6_src)) 346 goto freeit; 347 348 /* 349 * If we are about to send ICMPv6 against ICMPv6 error/redirect, 350 * don't do it. 351 */ 352 nxt = -1; 353 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); 354 if (off >= 0 && nxt == IPPROTO_ICMPV6) { 355 struct icmp6_hdr *icp; 356 357 IP6_EXTHDR_GET(icp, struct icmp6_hdr *, m, off, 358 sizeof(*icp)); 359 if (icp == NULL) { 360 ICMP6_STATINC(ICMP6_STAT_TOOSHORT); 361 return; 362 } 363 if (icp->icmp6_type < ICMP6_ECHO_REQUEST || 364 icp->icmp6_type == ND_REDIRECT) { 365 /* 366 * ICMPv6 error 367 * Special case: for redirect (which is 368 * informational) we must not send icmp6 error. 369 */ 370 ICMP6_STATINC(ICMP6_STAT_CANTERROR); 371 goto freeit; 372 } else { 373 /* ICMPv6 informational - send the error */ 374 } 375 } 376 #if 0 /* controversial */ 377 else if (off >= 0 && nxt == IPPROTO_ESP) { 378 /* 379 * It could be ICMPv6 error inside ESP. Take a safer side, 380 * don't respond. 381 */ 382 ICMP6_STATINC(ICMP6_STAT_CANTERROR); 383 goto freeit; 384 } 385 #endif 386 else { 387 /* non-ICMPv6 - send the error */ 388 } 389 390 oip6 = mtod(m, struct ip6_hdr *); /* adjust pointer */ 391 392 /* Finally, do rate limitation check. */ 393 if (icmp6_ratelimit(&oip6->ip6_src, type, code)) { 394 ICMP6_STATINC(ICMP6_STAT_TOOFREQ); 395 goto freeit; 396 } 397 398 /* 399 * OK, ICMP6 can be generated. 400 */ 401 402 if (m->m_pkthdr.len >= ICMPV6_PLD_MAXLEN) 403 m_adj(m, ICMPV6_PLD_MAXLEN - m->m_pkthdr.len); 404 405 preplen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 406 M_PREPEND(m, preplen, M_DONTWAIT); 407 if (m && M_UNWRITABLE(m, preplen)) 408 m = m_pullup(m, preplen); 409 if (m == NULL) { 410 nd6log((LOG_DEBUG, "ENOBUFS in icmp6_error %d\n", __LINE__)); 411 return; 412 } 413 414 nip6 = mtod(m, struct ip6_hdr *); 415 nip6->ip6_src = oip6->ip6_src; 416 nip6->ip6_dst = oip6->ip6_dst; 417 418 in6_clearscope(&oip6->ip6_src); 419 in6_clearscope(&oip6->ip6_dst); 420 421 icmp6 = (struct icmp6_hdr *)(nip6 + 1); 422 icmp6->icmp6_type = type; 423 icmp6->icmp6_code = code; 424 icmp6->icmp6_pptr = htonl((u_int32_t)param); 425 426 /* 427 * icmp6_reflect() is designed to be in the input path. 428 * icmp6_error() can be called from both input and output path, 429 * and if we are in output path rcvif could contain bogus value. 430 * clear m->m_pkthdr.rcvif for safety, we should have enough scope 431 * information in ip header (nip6). 432 */ 433 m->m_pkthdr.rcvif = NULL; 434 435 ICMP6_STATINC(ICMP6_STAT_OUTHIST + type); 436 icmp6_reflect(m, sizeof(struct ip6_hdr)); /* header order: IPv6 - ICMPv6 */ 437 438 return; 439 440 freeit: 441 /* 442 * If we can't tell whether or not we can generate ICMP6, free it. 443 */ 444 m_freem(m); 445 } 446 447 /* 448 * Process a received ICMP6 message. 449 */ 450 int 451 icmp6_input(struct mbuf **mp, int *offp, int proto) 452 { 453 struct mbuf *m = *mp, *n; 454 struct ip6_hdr *ip6, *nip6; 455 struct icmp6_hdr *icmp6, *nicmp6; 456 int off = *offp; 457 int icmp6len = m->m_pkthdr.len - *offp; 458 int code, sum, noff, i; 459 460 #define ICMP6_MAXLEN (sizeof(*nip6) + sizeof(*nicmp6) + 4) 461 KASSERT(ICMP6_MAXLEN < MCLBYTES); 462 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_msg); 463 464 /* 465 * Locate icmp6 structure in mbuf, and check 466 * that not corrupted and of at least minimum length 467 */ 468 469 if (icmp6len < sizeof(struct icmp6_hdr)) { 470 ICMP6_STATINC(ICMP6_STAT_TOOSHORT); 471 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_error); 472 goto freeit; 473 } 474 475 i = off + sizeof(*icmp6); 476 if ((m->m_len < i || M_READONLY(m)) && (m = m_pullup(m, i)) == 0) { 477 ICMP6_STATINC(ICMP6_STAT_TOOSHORT); 478 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_error); 479 goto freeit; 480 } 481 ip6 = mtod(m, struct ip6_hdr *); 482 /* 483 * calculate the checksum 484 */ 485 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 486 if (icmp6 == NULL) { 487 ICMP6_STATINC(ICMP6_STAT_TOOSHORT); 488 /* m is invalid */ 489 /*icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_error);*/ 490 return IPPROTO_DONE; 491 } 492 KASSERT(IP6_HDR_ALIGNED_P(icmp6)); 493 code = icmp6->icmp6_code; 494 495 if ((sum = in6_cksum(m, IPPROTO_ICMPV6, off, icmp6len)) != 0) { 496 nd6log((LOG_ERR, 497 "ICMP6 checksum error(%d|%x) %s\n", 498 icmp6->icmp6_type, sum, ip6_sprintf(&ip6->ip6_src))); 499 ICMP6_STATINC(ICMP6_STAT_CHECKSUM); 500 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_error); 501 goto freeit; 502 } 503 504 #if defined(NFAITH) && 0 < NFAITH 505 if (faithprefix(&ip6->ip6_dst)) { 506 /* 507 * Deliver very specific ICMP6 type only. 508 * This is important to deliver TOOBIG. Otherwise PMTUD 509 * will not work. 510 */ 511 switch (icmp6->icmp6_type) { 512 case ICMP6_DST_UNREACH: 513 case ICMP6_PACKET_TOO_BIG: 514 case ICMP6_TIME_EXCEEDED: 515 break; 516 default: 517 goto freeit; 518 } 519 } 520 #endif 521 522 ICMP6_STATINC(ICMP6_STAT_INHIST + icmp6->icmp6_type); 523 524 switch (icmp6->icmp6_type) { 525 case ICMP6_DST_UNREACH: 526 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_dstunreach); 527 switch (code) { 528 case ICMP6_DST_UNREACH_NOROUTE: 529 code = PRC_UNREACH_NET; 530 break; 531 case ICMP6_DST_UNREACH_ADMIN: 532 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_adminprohib); 533 code = PRC_UNREACH_PROTOCOL; /* is this a good code? */ 534 break; 535 case ICMP6_DST_UNREACH_ADDR: 536 code = PRC_HOSTDEAD; 537 break; 538 #ifdef COMPAT_RFC1885 539 case ICMP6_DST_UNREACH_NOTNEIGHBOR: 540 code = PRC_UNREACH_SRCFAIL; 541 break; 542 #else 543 case ICMP6_DST_UNREACH_BEYONDSCOPE: 544 /* I mean "source address was incorrect." */ 545 code = PRC_UNREACH_NET; 546 break; 547 #endif 548 case ICMP6_DST_UNREACH_NOPORT: 549 code = PRC_UNREACH_PORT; 550 break; 551 default: 552 goto badcode; 553 } 554 goto deliver; 555 556 case ICMP6_PACKET_TOO_BIG: 557 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_pkttoobig); 558 559 code = PRC_MSGSIZE; 560 561 /* 562 * Updating the path MTU will be done after examining 563 * intermediate extension headers. 564 */ 565 goto deliver; 566 567 case ICMP6_TIME_EXCEEDED: 568 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_timeexceed); 569 switch (code) { 570 case ICMP6_TIME_EXCEED_TRANSIT: 571 code = PRC_TIMXCEED_INTRANS; 572 break; 573 case ICMP6_TIME_EXCEED_REASSEMBLY: 574 code = PRC_TIMXCEED_REASS; 575 break; 576 default: 577 goto badcode; 578 } 579 goto deliver; 580 581 case ICMP6_PARAM_PROB: 582 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_paramprob); 583 switch (code) { 584 case ICMP6_PARAMPROB_NEXTHEADER: 585 code = PRC_UNREACH_PROTOCOL; 586 break; 587 case ICMP6_PARAMPROB_HEADER: 588 case ICMP6_PARAMPROB_OPTION: 589 code = PRC_PARAMPROB; 590 break; 591 default: 592 goto badcode; 593 } 594 goto deliver; 595 596 case ICMP6_ECHO_REQUEST: 597 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echo); 598 if (code != 0) 599 goto badcode; 600 /* 601 * Copy mbuf to send to two data paths: userland socket(s), 602 * and to the querier (echo reply). 603 * m: a copy for socket, n: a copy for querier 604 * 605 * If the first mbuf is shared, or the first mbuf is too short, 606 * copy the first part of the data into a fresh mbuf. 607 * Otherwise, we will wrongly overwrite both copies. 608 */ 609 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 610 /* Give up local */ 611 n = m; 612 m = NULL; 613 } else if (M_READONLY(n) || 614 n->m_len < off + sizeof(struct icmp6_hdr)) { 615 struct mbuf *n0 = n; 616 617 /* 618 * Prepare an internal mbuf. m_pullup() doesn't 619 * always copy the length we specified. 620 */ 621 if ((n = m_dup(n0, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 622 /* Give up local */ 623 n = m; 624 m = NULL; 625 } 626 m_freem(n0); 627 } 628 IP6_EXTHDR_GET(nicmp6, struct icmp6_hdr *, n, off, 629 sizeof(*nicmp6)); 630 nicmp6->icmp6_type = ICMP6_ECHO_REPLY; 631 nicmp6->icmp6_code = 0; 632 if (n) { 633 uint64_t *icmp6s = ICMP6_STAT_GETREF(); 634 icmp6s[ICMP6_STAT_REFLECT]++; 635 icmp6s[ICMP6_STAT_OUTHIST + ICMP6_ECHO_REPLY]++; 636 ICMP6_STAT_PUTREF(); 637 icmp6_reflect(n, off); 638 } 639 if (!m) 640 goto freeit; 641 break; 642 643 case ICMP6_ECHO_REPLY: 644 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echoreply); 645 if (code != 0) 646 goto badcode; 647 break; 648 649 case MLD_LISTENER_QUERY: 650 case MLD_LISTENER_REPORT: 651 if (icmp6len < sizeof(struct mld_hdr)) 652 goto badlen; 653 if (icmp6->icmp6_type == MLD_LISTENER_QUERY) /* XXX: ugly... */ 654 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldquery); 655 else 656 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldreport); 657 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 658 /* give up local */ 659 mld_input(m, off); 660 m = NULL; 661 goto freeit; 662 } 663 mld_input(n, off); 664 /* m stays. */ 665 break; 666 667 case MLD_LISTENER_DONE: 668 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mlddone); 669 if (icmp6len < sizeof(struct mld_hdr)) /* necessary? */ 670 goto badlen; 671 break; /* nothing to be done in kernel */ 672 673 case MLD_MTRACE_RESP: 674 case MLD_MTRACE: 675 /* XXX: these two are experimental. not officially defined. */ 676 /* XXX: per-interface statistics? */ 677 break; /* just pass it to applications */ 678 679 case ICMP6_WRUREQUEST: /* ICMP6_FQDN_QUERY */ 680 { 681 enum { WRU, FQDN } mode; 682 683 if (!icmp6_nodeinfo) 684 break; 685 686 if (icmp6len == sizeof(struct icmp6_hdr) + 4) 687 mode = WRU; 688 else if (icmp6len >= sizeof(struct icmp6_nodeinfo)) 689 mode = FQDN; 690 else 691 goto badlen; 692 693 if (mode == FQDN) { 694 n = m_copym(m, 0, M_COPYALL, M_DONTWAIT); 695 if (n) 696 n = ni6_input(n, off); 697 /* XXX meaningless if n == NULL */ 698 noff = sizeof(struct ip6_hdr); 699 } else { 700 u_char *p; 701 int maxhlen; 702 703 if ((icmp6_nodeinfo & 5) != 5) 704 break; 705 706 if (code != 0) 707 goto badcode; 708 MGETHDR(n, M_DONTWAIT, m->m_type); 709 if (n && ICMP6_MAXLEN > MHLEN) { 710 MCLGET(n, M_DONTWAIT); 711 if ((n->m_flags & M_EXT) == 0) { 712 m_free(n); 713 n = NULL; 714 } 715 } 716 if (n == NULL) { 717 /* Give up remote */ 718 break; 719 } 720 n->m_pkthdr.rcvif = NULL; 721 n->m_len = 0; 722 maxhlen = M_TRAILINGSPACE(n) - ICMP6_MAXLEN; 723 if (maxhlen > hostnamelen) 724 maxhlen = hostnamelen; 725 /* 726 * Copy IPv6 and ICMPv6 only. 727 */ 728 nip6 = mtod(n, struct ip6_hdr *); 729 bcopy(ip6, nip6, sizeof(struct ip6_hdr)); 730 nicmp6 = (struct icmp6_hdr *)(nip6 + 1); 731 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr)); 732 p = (u_char *)(nicmp6 + 1); 733 bzero(p, 4); 734 bcopy(hostname, p + 4, maxhlen); /* meaningless TTL */ 735 noff = sizeof(struct ip6_hdr); 736 M_COPY_PKTHDR(n, m); /* just for rcvif */ 737 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) + 738 sizeof(struct icmp6_hdr) + 4 + maxhlen; 739 nicmp6->icmp6_type = ICMP6_WRUREPLY; 740 nicmp6->icmp6_code = 0; 741 } 742 #undef hostnamelen 743 if (n) { 744 uint64_t *icmp6s = ICMP6_STAT_GETREF(); 745 icmp6s[ICMP6_STAT_REFLECT]++; 746 icmp6s[ICMP6_STAT_OUTHIST + ICMP6_WRUREPLY]++; 747 ICMP6_STAT_PUTREF(); 748 icmp6_reflect(n, noff); 749 } 750 break; 751 } 752 753 case ICMP6_WRUREPLY: 754 if (code != 0) 755 goto badcode; 756 break; 757 758 case ND_ROUTER_SOLICIT: 759 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routersolicit); 760 if (code != 0) 761 goto badcode; 762 if (icmp6len < sizeof(struct nd_router_solicit)) 763 goto badlen; 764 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 765 /* give up local */ 766 nd6_rs_input(m, off, icmp6len); 767 m = NULL; 768 goto freeit; 769 } 770 nd6_rs_input(n, off, icmp6len); 771 /* m stays. */ 772 break; 773 774 case ND_ROUTER_ADVERT: 775 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routeradvert); 776 if (code != 0) 777 goto badcode; 778 if (icmp6len < sizeof(struct nd_router_advert)) 779 goto badlen; 780 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 781 /* give up local */ 782 nd6_ra_input(m, off, icmp6len); 783 m = NULL; 784 goto freeit; 785 } 786 nd6_ra_input(n, off, icmp6len); 787 /* m stays. */ 788 break; 789 790 case ND_NEIGHBOR_SOLICIT: 791 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighborsolicit); 792 if (code != 0) 793 goto badcode; 794 if (icmp6len < sizeof(struct nd_neighbor_solicit)) 795 goto badlen; 796 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 797 /* give up local */ 798 nd6_ns_input(m, off, icmp6len); 799 m = NULL; 800 goto freeit; 801 } 802 nd6_ns_input(n, off, icmp6len); 803 /* m stays. */ 804 break; 805 806 case ND_NEIGHBOR_ADVERT: 807 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighboradvert); 808 if (code != 0) 809 goto badcode; 810 if (icmp6len < sizeof(struct nd_neighbor_advert)) 811 goto badlen; 812 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 813 /* give up local */ 814 nd6_na_input(m, off, icmp6len); 815 m = NULL; 816 goto freeit; 817 } 818 nd6_na_input(n, off, icmp6len); 819 /* m stays. */ 820 break; 821 822 case ND_REDIRECT: 823 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_redirect); 824 if (code != 0) 825 goto badcode; 826 if (icmp6len < sizeof(struct nd_redirect)) 827 goto badlen; 828 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 829 /* give up local */ 830 icmp6_redirect_input(m, off); 831 m = NULL; 832 goto freeit; 833 } 834 icmp6_redirect_input(n, off); 835 /* m stays. */ 836 break; 837 838 case ICMP6_ROUTER_RENUMBERING: 839 if (code != ICMP6_ROUTER_RENUMBERING_COMMAND && 840 code != ICMP6_ROUTER_RENUMBERING_RESULT) 841 goto badcode; 842 if (icmp6len < sizeof(struct icmp6_router_renum)) 843 goto badlen; 844 break; 845 846 default: 847 nd6log((LOG_DEBUG, 848 "icmp6_input: unknown type %d(src=%s, dst=%s, ifid=%d)\n", 849 icmp6->icmp6_type, ip6_sprintf(&ip6->ip6_src), 850 ip6_sprintf(&ip6->ip6_dst), 851 m->m_pkthdr.rcvif ? m->m_pkthdr.rcvif->if_index : 0)); 852 if (icmp6->icmp6_type < ICMP6_ECHO_REQUEST) { 853 /* ICMPv6 error: MUST deliver it by spec... */ 854 code = PRC_NCMDS; 855 /* deliver */ 856 } else { 857 /* ICMPv6 informational: MUST not deliver */ 858 break; 859 } 860 deliver: 861 if (icmp6_notify_error(m, off, icmp6len, code)) { 862 /* In this case, m should've been freed. */ 863 return (IPPROTO_DONE); 864 } 865 break; 866 867 badcode: 868 ICMP6_STATINC(ICMP6_STAT_BADCODE); 869 break; 870 871 badlen: 872 ICMP6_STATINC(ICMP6_STAT_BADLEN); 873 break; 874 } 875 876 /* deliver the packet to appropriate sockets */ 877 icmp6_rip6_input(&m, *offp); 878 879 return IPPROTO_DONE; 880 881 freeit: 882 m_freem(m); 883 return IPPROTO_DONE; 884 } 885 886 static int 887 icmp6_notify_error(struct mbuf *m, int off, int icmp6len, int code) 888 { 889 struct icmp6_hdr *icmp6; 890 struct ip6_hdr *eip6; 891 u_int32_t notifymtu; 892 struct sockaddr_in6 icmp6src, icmp6dst; 893 894 if (icmp6len < sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr)) { 895 ICMP6_STATINC(ICMP6_STAT_TOOSHORT); 896 goto freeit; 897 } 898 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, 899 sizeof(*icmp6) + sizeof(struct ip6_hdr)); 900 if (icmp6 == NULL) { 901 ICMP6_STATINC(ICMP6_STAT_TOOSHORT); 902 return (-1); 903 } 904 eip6 = (struct ip6_hdr *)(icmp6 + 1); 905 906 /* Detect the upper level protocol */ 907 { 908 void (*ctlfunc)(int, struct sockaddr *, void *); 909 u_int8_t nxt = eip6->ip6_nxt; 910 int eoff = off + sizeof(struct icmp6_hdr) + 911 sizeof(struct ip6_hdr); 912 struct ip6ctlparam ip6cp; 913 struct in6_addr *finaldst = NULL; 914 int icmp6type = icmp6->icmp6_type; 915 struct ip6_frag *fh; 916 struct ip6_rthdr *rth; 917 struct ip6_rthdr0 *rth0; 918 int rthlen; 919 920 while (1) { /* XXX: should avoid infinite loop explicitly? */ 921 struct ip6_ext *eh; 922 923 switch (nxt) { 924 case IPPROTO_HOPOPTS: 925 case IPPROTO_DSTOPTS: 926 case IPPROTO_AH: 927 IP6_EXTHDR_GET(eh, struct ip6_ext *, m, 928 eoff, sizeof(*eh)); 929 if (eh == NULL) { 930 ICMP6_STATINC(ICMP6_STAT_TOOSHORT); 931 return (-1); 932 } 933 934 if (nxt == IPPROTO_AH) 935 eoff += (eh->ip6e_len + 2) << 2; 936 else 937 eoff += (eh->ip6e_len + 1) << 3; 938 nxt = eh->ip6e_nxt; 939 break; 940 case IPPROTO_ROUTING: 941 /* 942 * When the erroneous packet contains a 943 * routing header, we should examine the 944 * header to determine the final destination. 945 * Otherwise, we can't properly update 946 * information that depends on the final 947 * destination (e.g. path MTU). 948 */ 949 IP6_EXTHDR_GET(rth, struct ip6_rthdr *, m, 950 eoff, sizeof(*rth)); 951 if (rth == NULL) { 952 ICMP6_STATINC(ICMP6_STAT_TOOSHORT); 953 return (-1); 954 } 955 rthlen = (rth->ip6r_len + 1) << 3; 956 /* 957 * XXX: currently there is no 958 * officially defined type other 959 * than type-0. 960 * Note that if the segment left field 961 * is 0, all intermediate hops must 962 * have been passed. 963 */ 964 if (rth->ip6r_segleft && 965 rth->ip6r_type == IPV6_RTHDR_TYPE_0) { 966 int hops; 967 968 IP6_EXTHDR_GET(rth0, 969 struct ip6_rthdr0 *, m, 970 eoff, rthlen); 971 if (rth0 == NULL) { 972 ICMP6_STATINC(ICMP6_STAT_TOOSHORT); 973 return (-1); 974 } 975 /* just ignore a bogus header */ 976 if ((rth0->ip6r0_len % 2) == 0 && 977 (hops = rth0->ip6r0_len/2)) 978 finaldst = (struct in6_addr *)(rth0 + 1) + (hops - 1); 979 } 980 eoff += rthlen; 981 nxt = rth->ip6r_nxt; 982 break; 983 case IPPROTO_FRAGMENT: 984 IP6_EXTHDR_GET(fh, struct ip6_frag *, m, 985 eoff, sizeof(*fh)); 986 if (fh == NULL) { 987 ICMP6_STATINC(ICMP6_STAT_TOOSHORT); 988 return (-1); 989 } 990 /* 991 * Data after a fragment header is meaningless 992 * unless it is the first fragment, but 993 * we'll go to the notify label for path MTU 994 * discovery. 995 */ 996 if (fh->ip6f_offlg & IP6F_OFF_MASK) 997 goto notify; 998 999 eoff += sizeof(struct ip6_frag); 1000 nxt = fh->ip6f_nxt; 1001 break; 1002 default: 1003 /* 1004 * This case includes ESP and the No Next 1005 * Header. In such cases going to the notify 1006 * label does not have any meaning 1007 * (i.e. ctlfunc will be NULL), but we go 1008 * anyway since we might have to update 1009 * path MTU information. 1010 */ 1011 goto notify; 1012 } 1013 } 1014 notify: 1015 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, 1016 sizeof(*icmp6) + sizeof(struct ip6_hdr)); 1017 if (icmp6 == NULL) { 1018 ICMP6_STATINC(ICMP6_STAT_TOOSHORT); 1019 return (-1); 1020 } 1021 1022 /* 1023 * retrieve parameters from the inner IPv6 header, and convert 1024 * them into sockaddr structures. 1025 * XXX: there is no guarantee that the source or destination 1026 * addresses of the inner packet are in the same scope zone as 1027 * the addresses of the icmp packet. But there is no other 1028 * way to determine the zone. 1029 */ 1030 eip6 = (struct ip6_hdr *)(icmp6 + 1); 1031 1032 sockaddr_in6_init(&icmp6dst, 1033 (finaldst == NULL) ? &eip6->ip6_dst : finaldst, 0, 0, 0); 1034 if (in6_setscope(&icmp6dst.sin6_addr, m->m_pkthdr.rcvif, NULL)) 1035 goto freeit; 1036 sockaddr_in6_init(&icmp6src, &eip6->ip6_src, 0, 0, 0); 1037 if (in6_setscope(&icmp6src.sin6_addr, m->m_pkthdr.rcvif, NULL)) 1038 goto freeit; 1039 icmp6src.sin6_flowinfo = 1040 (eip6->ip6_flow & IPV6_FLOWLABEL_MASK); 1041 1042 if (finaldst == NULL) 1043 finaldst = &eip6->ip6_dst; 1044 ip6cp.ip6c_m = m; 1045 ip6cp.ip6c_icmp6 = icmp6; 1046 ip6cp.ip6c_ip6 = (struct ip6_hdr *)(icmp6 + 1); 1047 ip6cp.ip6c_off = eoff; 1048 ip6cp.ip6c_finaldst = finaldst; 1049 ip6cp.ip6c_src = &icmp6src; 1050 ip6cp.ip6c_nxt = nxt; 1051 1052 if (icmp6type == ICMP6_PACKET_TOO_BIG) { 1053 notifymtu = ntohl(icmp6->icmp6_mtu); 1054 ip6cp.ip6c_cmdarg = (void *)¬ifymtu; 1055 } 1056 1057 ctlfunc = (void (*)(int, struct sockaddr *, void *)) 1058 (inet6sw[ip6_protox[nxt]].pr_ctlinput); 1059 if (ctlfunc) { 1060 (void) (*ctlfunc)(code, (struct sockaddr *)&icmp6dst, 1061 &ip6cp); 1062 } 1063 } 1064 return (0); 1065 1066 freeit: 1067 m_freem(m); 1068 return (-1); 1069 } 1070 1071 void 1072 icmp6_mtudisc_update(struct ip6ctlparam *ip6cp, 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 ICMP6_STATINC(ICMP6_STAT_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(struct mbuf *m, int off) 1148 { 1149 struct icmp6_nodeinfo *ni6, *nni6; 1150 struct mbuf *n = NULL; 1151 u_int16_t qtype; 1152 int subjlen; 1153 int replylen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo); 1154 struct ni_reply_fqdn *fqdn; 1155 int addrs; /* for NI_QTYPE_NODEADDR */ 1156 struct ifnet *ifp = NULL; /* for NI_QTYPE_NODEADDR */ 1157 struct sockaddr_in6 sin6; /* ip6_dst */ 1158 struct in6_addr in6_subj; /* subject address */ 1159 struct ip6_hdr *ip6; 1160 int oldfqdn = 0; /* if 1, return pascal string (03 draft) */ 1161 char *subj = NULL; 1162 1163 ip6 = mtod(m, struct ip6_hdr *); 1164 IP6_EXTHDR_GET(ni6, struct icmp6_nodeinfo *, m, off, sizeof(*ni6)); 1165 if (ni6 == NULL) { 1166 /* m is already reclaimed */ 1167 return NULL; 1168 } 1169 1170 /* 1171 * Validate IPv6 destination address. 1172 * 1173 * The Responder must discard the Query without further processing 1174 * unless it is one of the Responder's unicast or anycast addresses, or 1175 * a link-local scope multicast address which the Responder has joined. 1176 * [icmp-name-lookups-07, Section 4.] 1177 */ 1178 sockaddr_in6_init(&sin6, &ip6->ip6_dst, 0, 0, 0); 1179 /* XXX scopeid */ 1180 if (ifa_ifwithaddr((struct sockaddr *)&sin6)) 1181 ; /* unicast/anycast, fine */ 1182 else if (IN6_IS_ADDR_MC_LINKLOCAL(&sin6.sin6_addr)) 1183 ; /* link-local multicast, fine */ 1184 else 1185 goto bad; 1186 1187 /* validate query Subject field. */ 1188 qtype = ntohs(ni6->ni_qtype); 1189 subjlen = m->m_pkthdr.len - off - sizeof(struct icmp6_nodeinfo); 1190 switch (qtype) { 1191 case NI_QTYPE_NOOP: 1192 case NI_QTYPE_SUPTYPES: 1193 /* 07 draft */ 1194 if (ni6->ni_code == ICMP6_NI_SUBJ_FQDN && subjlen == 0) 1195 break; 1196 /* FALLTHROUGH */ 1197 case NI_QTYPE_FQDN: 1198 case NI_QTYPE_NODEADDR: 1199 case NI_QTYPE_IPV4ADDR: 1200 switch (ni6->ni_code) { 1201 case ICMP6_NI_SUBJ_IPV6: 1202 #if ICMP6_NI_SUBJ_IPV6 != 0 1203 case 0: 1204 #endif 1205 /* 1206 * backward compatibility - try to accept 03 draft 1207 * format, where no Subject is present. 1208 */ 1209 if (qtype == NI_QTYPE_FQDN && ni6->ni_code == 0 && 1210 subjlen == 0) { 1211 oldfqdn++; 1212 break; 1213 } 1214 #if ICMP6_NI_SUBJ_IPV6 != 0 1215 if (ni6->ni_code != ICMP6_NI_SUBJ_IPV6) 1216 goto bad; 1217 #endif 1218 1219 if (subjlen != sizeof(sin6.sin6_addr)) 1220 goto bad; 1221 1222 /* 1223 * Validate Subject address. 1224 * 1225 * Not sure what exactly "address belongs to the node" 1226 * means in the spec, is it just unicast, or what? 1227 * 1228 * At this moment we consider Subject address as 1229 * "belong to the node" if the Subject address equals 1230 * to the IPv6 destination address; validation for 1231 * IPv6 destination address should have done enough 1232 * check for us. 1233 * 1234 * We do not do proxy at this moment. 1235 */ 1236 /* m_pulldown instead of copy? */ 1237 m_copydata(m, off + sizeof(struct icmp6_nodeinfo), 1238 subjlen, (void *)&in6_subj); 1239 if (in6_setscope(&in6_subj, m->m_pkthdr.rcvif, NULL)) 1240 goto bad; 1241 1242 subj = (char *)&in6_subj; 1243 if (IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, &in6_subj)) 1244 break; 1245 1246 /* 1247 * XXX if we are to allow other cases, we should really 1248 * be careful about scope here. 1249 * basically, we should disallow queries toward IPv6 1250 * destination X with subject Y, if scope(X) > scope(Y). 1251 * if we allow scope(X) > scope(Y), it will result in 1252 * information leakage across scope boundary. 1253 */ 1254 goto bad; 1255 1256 case ICMP6_NI_SUBJ_FQDN: 1257 /* 1258 * Validate Subject name with gethostname(3). 1259 * 1260 * The behavior may need some debate, since: 1261 * - we are not sure if the node has FQDN as 1262 * hostname (returned by gethostname(3)). 1263 * - the code does wildcard match for truncated names. 1264 * however, we are not sure if we want to perform 1265 * wildcard match, if gethostname(3) side has 1266 * truncated hostname. 1267 */ 1268 n = ni6_nametodns(hostname, hostnamelen, 0); 1269 if (!n || n->m_next || n->m_len == 0) 1270 goto bad; 1271 IP6_EXTHDR_GET(subj, char *, m, 1272 off + sizeof(struct icmp6_nodeinfo), subjlen); 1273 if (subj == NULL) 1274 goto bad; 1275 if (!ni6_dnsmatch(subj, subjlen, mtod(n, const char *), 1276 n->m_len)) { 1277 goto bad; 1278 } 1279 m_freem(n); 1280 n = NULL; 1281 break; 1282 1283 case ICMP6_NI_SUBJ_IPV4: /* XXX: to be implemented? */ 1284 default: 1285 goto bad; 1286 } 1287 break; 1288 } 1289 1290 /* refuse based on configuration. XXX ICMP6_NI_REFUSED? */ 1291 switch (qtype) { 1292 case NI_QTYPE_FQDN: 1293 if ((icmp6_nodeinfo & 1) == 0) 1294 goto bad; 1295 break; 1296 case NI_QTYPE_NODEADDR: 1297 case NI_QTYPE_IPV4ADDR: 1298 if ((icmp6_nodeinfo & 2) == 0) 1299 goto bad; 1300 break; 1301 } 1302 1303 /* guess reply length */ 1304 switch (qtype) { 1305 case NI_QTYPE_NOOP: 1306 break; /* no reply data */ 1307 case NI_QTYPE_SUPTYPES: 1308 replylen += sizeof(u_int32_t); 1309 break; 1310 case NI_QTYPE_FQDN: 1311 /* XXX will append an mbuf */ 1312 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1313 break; 1314 case NI_QTYPE_NODEADDR: 1315 addrs = ni6_addrs(ni6, m, &ifp, subj); 1316 if ((replylen += addrs * (sizeof(struct in6_addr) + 1317 sizeof(u_int32_t))) > MCLBYTES) 1318 replylen = MCLBYTES; /* XXX: will truncate pkt later */ 1319 break; 1320 case NI_QTYPE_IPV4ADDR: 1321 /* unsupported - should respond with unknown Qtype? */ 1322 goto bad; 1323 default: 1324 /* 1325 * XXX: We must return a reply with the ICMP6 code 1326 * `unknown Qtype' in this case. However we regard the case 1327 * as an FQDN query for backward compatibility. 1328 * Older versions set a random value to this field, 1329 * so it rarely varies in the defined qtypes. 1330 * But the mechanism is not reliable... 1331 * maybe we should obsolete older versions. 1332 */ 1333 qtype = NI_QTYPE_FQDN; 1334 /* XXX will append an mbuf */ 1335 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1336 oldfqdn++; 1337 break; 1338 } 1339 1340 /* allocate an mbuf to reply. */ 1341 MGETHDR(n, M_DONTWAIT, m->m_type); 1342 if (n == NULL) { 1343 m_freem(m); 1344 return (NULL); 1345 } 1346 M_MOVE_PKTHDR(n, m); /* just for rcvif */ 1347 if (replylen > MHLEN) { 1348 if (replylen > MCLBYTES) { 1349 /* 1350 * XXX: should we try to allocate more? But MCLBYTES 1351 * is probably much larger than IPV6_MMTU... 1352 */ 1353 goto bad; 1354 } 1355 MCLGET(n, M_DONTWAIT); 1356 if ((n->m_flags & M_EXT) == 0) { 1357 goto bad; 1358 } 1359 } 1360 n->m_pkthdr.len = n->m_len = replylen; 1361 1362 /* copy mbuf header and IPv6 + Node Information base headers */ 1363 bcopy(mtod(m, void *), mtod(n, void *), sizeof(struct ip6_hdr)); 1364 nni6 = (struct icmp6_nodeinfo *)(mtod(n, struct ip6_hdr *) + 1); 1365 bcopy((void *)ni6, (void *)nni6, sizeof(struct icmp6_nodeinfo)); 1366 1367 /* qtype dependent procedure */ 1368 switch (qtype) { 1369 case NI_QTYPE_NOOP: 1370 nni6->ni_code = ICMP6_NI_SUCCESS; 1371 nni6->ni_flags = 0; 1372 break; 1373 case NI_QTYPE_SUPTYPES: 1374 { 1375 u_int32_t v; 1376 nni6->ni_code = ICMP6_NI_SUCCESS; 1377 nni6->ni_flags = htons(0x0000); /* raw bitmap */ 1378 /* supports NOOP, SUPTYPES, FQDN, and NODEADDR */ 1379 v = (u_int32_t)htonl(0x0000000f); 1380 bcopy(&v, nni6 + 1, sizeof(u_int32_t)); 1381 break; 1382 } 1383 case NI_QTYPE_FQDN: 1384 nni6->ni_code = ICMP6_NI_SUCCESS; 1385 fqdn = (struct ni_reply_fqdn *)(mtod(n, char *) + 1386 sizeof(struct ip6_hdr) + 1387 sizeof(struct icmp6_nodeinfo)); 1388 nni6->ni_flags = 0; /* XXX: meaningless TTL */ 1389 fqdn->ni_fqdn_ttl = 0; /* ditto. */ 1390 /* 1391 * XXX do we really have FQDN in variable "hostname"? 1392 */ 1393 n->m_next = ni6_nametodns(hostname, hostnamelen, oldfqdn); 1394 if (n->m_next == NULL) 1395 goto bad; 1396 /* XXX we assume that n->m_next is not a chain */ 1397 if (n->m_next->m_next != NULL) 1398 goto bad; 1399 n->m_pkthdr.len += n->m_next->m_len; 1400 break; 1401 case NI_QTYPE_NODEADDR: 1402 { 1403 int lenlim, copied; 1404 1405 nni6->ni_code = ICMP6_NI_SUCCESS; 1406 n->m_pkthdr.len = n->m_len = 1407 sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo); 1408 lenlim = M_TRAILINGSPACE(n); 1409 copied = ni6_store_addrs(ni6, nni6, ifp, lenlim); 1410 /* XXX: reset mbuf length */ 1411 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) + 1412 sizeof(struct icmp6_nodeinfo) + copied; 1413 break; 1414 } 1415 default: 1416 break; /* XXX impossible! */ 1417 } 1418 1419 nni6->ni_type = ICMP6_NI_REPLY; 1420 m_freem(m); 1421 return (n); 1422 1423 bad: 1424 m_freem(m); 1425 if (n) 1426 m_freem(n); 1427 return (NULL); 1428 } 1429 #undef hostnamelen 1430 1431 #define isupper(x) ('A' <= (x) && (x) <= 'Z') 1432 #define isalpha(x) (('A' <= (x) && (x) <= 'Z') || ('a' <= (x) && (x) <= 'z')) 1433 #define isalnum(x) (isalpha(x) || ('0' <= (x) && (x) <= '9')) 1434 #define tolower(x) (isupper(x) ? (x) + 'a' - 'A' : (x)) 1435 1436 /* 1437 * make a mbuf with DNS-encoded string. no compression support. 1438 * 1439 * XXX names with less than 2 dots (like "foo" or "foo.section") will be 1440 * treated as truncated name (two \0 at the end). this is a wild guess. 1441 * 1442 * old - return pascal string if non-zero 1443 */ 1444 static struct mbuf * 1445 ni6_nametodns(const char *name, int namelen, int old) 1446 { 1447 struct mbuf *m; 1448 char *cp, *ep; 1449 const char *p, *q; 1450 int i, len, nterm; 1451 1452 if (old) 1453 len = namelen + 1; 1454 else 1455 len = MCLBYTES; 1456 1457 /* because MAXHOSTNAMELEN is usually 256, we use cluster mbuf */ 1458 MGET(m, M_DONTWAIT, MT_DATA); 1459 if (m && len > MLEN) { 1460 MCLGET(m, M_DONTWAIT); 1461 if ((m->m_flags & M_EXT) == 0) 1462 goto fail; 1463 } 1464 if (!m) 1465 goto fail; 1466 m->m_next = NULL; 1467 1468 if (old) { 1469 m->m_len = len; 1470 *mtod(m, char *) = namelen; 1471 bcopy(name, mtod(m, char *) + 1, namelen); 1472 return m; 1473 } else { 1474 m->m_len = 0; 1475 cp = mtod(m, char *); 1476 ep = mtod(m, char *) + M_TRAILINGSPACE(m); 1477 1478 /* if not certain about my name, return empty buffer */ 1479 if (namelen == 0) 1480 return m; 1481 1482 /* 1483 * guess if it looks like shortened hostname, or FQDN. 1484 * shortened hostname needs two trailing "\0". 1485 */ 1486 i = 0; 1487 for (p = name; p < name + namelen; p++) { 1488 if (*p && *p == '.') 1489 i++; 1490 } 1491 if (i < 2) 1492 nterm = 2; 1493 else 1494 nterm = 1; 1495 1496 p = name; 1497 while (cp < ep && p < name + namelen) { 1498 i = 0; 1499 for (q = p; q < name + namelen && *q && *q != '.'; q++) 1500 i++; 1501 /* result does not fit into mbuf */ 1502 if (cp + i + 1 >= ep) 1503 goto fail; 1504 /* 1505 * DNS label length restriction, RFC1035 page 8. 1506 * "i == 0" case is included here to avoid returning 1507 * 0-length label on "foo..bar". 1508 */ 1509 if (i <= 0 || i >= 64) 1510 goto fail; 1511 *cp++ = i; 1512 if (!isalpha(p[0]) || !isalnum(p[i - 1])) 1513 goto fail; 1514 while (i > 0) { 1515 if (!isalnum(*p) && *p != '-') 1516 goto fail; 1517 if (isupper(*p)) { 1518 *cp++ = tolower(*p); 1519 p++; 1520 } else 1521 *cp++ = *p++; 1522 i--; 1523 } 1524 p = q; 1525 if (p < name + namelen && *p == '.') 1526 p++; 1527 } 1528 /* termination */ 1529 if (cp + nterm >= ep) 1530 goto fail; 1531 while (nterm-- > 0) 1532 *cp++ = '\0'; 1533 m->m_len = cp - mtod(m, char *); 1534 return m; 1535 } 1536 1537 panic("should not reach here"); 1538 /* NOTREACHED */ 1539 1540 fail: 1541 if (m) 1542 m_freem(m); 1543 return NULL; 1544 } 1545 1546 /* 1547 * check if two DNS-encoded string matches. takes care of truncated 1548 * form (with \0\0 at the end). no compression support. 1549 * XXX upper/lowercase match (see RFC2065) 1550 */ 1551 static int 1552 ni6_dnsmatch(const char *a, int alen, const char *b, int blen) 1553 { 1554 const char *a0, *b0; 1555 int l; 1556 1557 /* simplest case - need validation? */ 1558 if (alen == blen && bcmp(a, b, alen) == 0) 1559 return 1; 1560 1561 a0 = a; 1562 b0 = b; 1563 1564 /* termination is mandatory */ 1565 if (alen < 2 || blen < 2) 1566 return 0; 1567 if (a0[alen - 1] != '\0' || b0[blen - 1] != '\0') 1568 return 0; 1569 alen--; 1570 blen--; 1571 1572 while (a - a0 < alen && b - b0 < blen) { 1573 if (a - a0 + 1 > alen || b - b0 + 1 > blen) 1574 return 0; 1575 1576 if ((signed char)a[0] < 0 || (signed char)b[0] < 0) 1577 return 0; 1578 /* we don't support compression yet */ 1579 if (a[0] >= 64 || b[0] >= 64) 1580 return 0; 1581 1582 /* truncated case */ 1583 if (a[0] == 0 && a - a0 == alen - 1) 1584 return 1; 1585 if (b[0] == 0 && b - b0 == blen - 1) 1586 return 1; 1587 if (a[0] == 0 || b[0] == 0) 1588 return 0; 1589 1590 if (a[0] != b[0]) 1591 return 0; 1592 l = a[0]; 1593 if (a - a0 + 1 + l > alen || b - b0 + 1 + l > blen) 1594 return 0; 1595 if (bcmp(a + 1, b + 1, l) != 0) 1596 return 0; 1597 1598 a += 1 + l; 1599 b += 1 + l; 1600 } 1601 1602 if (a - a0 == alen && b - b0 == blen) 1603 return 1; 1604 else 1605 return 0; 1606 } 1607 1608 /* 1609 * calculate the number of addresses to be returned in the node info reply. 1610 */ 1611 static int 1612 ni6_addrs(struct icmp6_nodeinfo *ni6, struct mbuf *m, 1613 struct ifnet **ifpp, char *subj) 1614 { 1615 struct ifnet *ifp; 1616 struct in6_ifaddr *ifa6; 1617 struct ifaddr *ifa; 1618 struct sockaddr_in6 *subj_ip6 = NULL; /* XXX pedant */ 1619 int addrs = 0, addrsofif, iffound = 0; 1620 int niflags = ni6->ni_flags; 1621 1622 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0) { 1623 switch (ni6->ni_code) { 1624 case ICMP6_NI_SUBJ_IPV6: 1625 if (subj == NULL) /* must be impossible... */ 1626 return (0); 1627 subj_ip6 = (struct sockaddr_in6 *)subj; 1628 break; 1629 default: 1630 /* 1631 * XXX: we only support IPv6 subject address for 1632 * this Qtype. 1633 */ 1634 return (0); 1635 } 1636 } 1637 1638 IFNET_FOREACH(ifp) { 1639 addrsofif = 0; 1640 IFADDR_FOREACH(ifa, ifp) { 1641 if (ifa->ifa_addr->sa_family != AF_INET6) 1642 continue; 1643 ifa6 = (struct in6_ifaddr *)ifa; 1644 1645 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0 && 1646 IN6_ARE_ADDR_EQUAL(&subj_ip6->sin6_addr, 1647 &ifa6->ia_addr.sin6_addr)) 1648 iffound = 1; 1649 1650 /* 1651 * IPv4-mapped addresses can only be returned by a 1652 * Node Information proxy, since they represent 1653 * addresses of IPv4-only nodes, which perforce do 1654 * not implement this protocol. 1655 * [icmp-name-lookups-07, Section 5.4] 1656 * So we don't support NI_NODEADDR_FLAG_COMPAT in 1657 * this function at this moment. 1658 */ 1659 1660 /* What do we have to do about ::1? */ 1661 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1662 case IPV6_ADDR_SCOPE_LINKLOCAL: 1663 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0) 1664 continue; 1665 break; 1666 case IPV6_ADDR_SCOPE_SITELOCAL: 1667 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0) 1668 continue; 1669 break; 1670 case IPV6_ADDR_SCOPE_GLOBAL: 1671 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0) 1672 continue; 1673 break; 1674 default: 1675 continue; 1676 } 1677 1678 /* 1679 * check if anycast is okay. 1680 * XXX: just experimental. not in the spec. 1681 */ 1682 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 && 1683 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0) 1684 continue; /* we need only unicast addresses */ 1685 1686 addrsofif++; /* count the address */ 1687 } 1688 if (iffound) { 1689 *ifpp = ifp; 1690 return (addrsofif); 1691 } 1692 1693 addrs += addrsofif; 1694 } 1695 1696 return (addrs); 1697 } 1698 1699 static int 1700 ni6_store_addrs(struct icmp6_nodeinfo *ni6, 1701 struct icmp6_nodeinfo *nni6, struct ifnet *ifp0, 1702 int resid) 1703 { 1704 struct ifnet *ifp = ifp0 ? ifp0 : TAILQ_FIRST(&ifnet); 1705 struct in6_ifaddr *ifa6; 1706 struct ifaddr *ifa; 1707 struct ifnet *ifp_dep = NULL; 1708 int copied = 0, allow_deprecated = 0; 1709 u_char *cp = (u_char *)(nni6 + 1); 1710 int niflags = ni6->ni_flags; 1711 u_int32_t ltime; 1712 1713 if (ifp0 == NULL && !(niflags & NI_NODEADDR_FLAG_ALL)) 1714 return (0); /* needless to copy */ 1715 1716 again: 1717 1718 for (; ifp; ifp = TAILQ_NEXT(ifp, if_list)) 1719 { 1720 IFADDR_FOREACH(ifa, ifp) { 1721 if (ifa->ifa_addr->sa_family != AF_INET6) 1722 continue; 1723 ifa6 = (struct in6_ifaddr *)ifa; 1724 1725 if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) != 0 && 1726 allow_deprecated == 0) { 1727 /* 1728 * prefererred address should be put before 1729 * deprecated addresses. 1730 */ 1731 1732 /* record the interface for later search */ 1733 if (ifp_dep == NULL) 1734 ifp_dep = ifp; 1735 1736 continue; 1737 } 1738 else if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) == 0 && 1739 allow_deprecated != 0) 1740 continue; /* we now collect deprecated addrs */ 1741 1742 /* What do we have to do about ::1? */ 1743 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1744 case IPV6_ADDR_SCOPE_LINKLOCAL: 1745 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0) 1746 continue; 1747 break; 1748 case IPV6_ADDR_SCOPE_SITELOCAL: 1749 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0) 1750 continue; 1751 break; 1752 case IPV6_ADDR_SCOPE_GLOBAL: 1753 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0) 1754 continue; 1755 break; 1756 default: 1757 continue; 1758 } 1759 1760 /* 1761 * check if anycast is okay. 1762 * XXX: just experimental. not in the spec. 1763 */ 1764 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 && 1765 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0) 1766 continue; 1767 1768 /* now we can copy the address */ 1769 if (resid < sizeof(struct in6_addr) + 1770 sizeof(u_int32_t)) { 1771 /* 1772 * We give up much more copy. 1773 * Set the truncate flag and return. 1774 */ 1775 nni6->ni_flags |= NI_NODEADDR_FLAG_TRUNCATE; 1776 return (copied); 1777 } 1778 1779 /* 1780 * Set the TTL of the address. 1781 * The TTL value should be one of the following 1782 * according to the specification: 1783 * 1784 * 1. The remaining lifetime of a DHCP lease on the 1785 * address, or 1786 * 2. The remaining Valid Lifetime of a prefix from 1787 * which the address was derived through Stateless 1788 * Autoconfiguration. 1789 * 1790 * Note that we currently do not support stateful 1791 * address configuration by DHCPv6, so the former 1792 * case can't happen. 1793 * 1794 * TTL must be 2^31 > TTL >= 0. 1795 */ 1796 if (ifa6->ia6_lifetime.ia6t_expire == 0) 1797 ltime = ND6_INFINITE_LIFETIME; 1798 else { 1799 if (ifa6->ia6_lifetime.ia6t_expire > 1800 time_second) 1801 ltime = ifa6->ia6_lifetime.ia6t_expire - 1802 time_second; 1803 else 1804 ltime = 0; 1805 } 1806 if (ltime > 0x7fffffff) 1807 ltime = 0x7fffffff; 1808 ltime = htonl(ltime); 1809 1810 bcopy(<ime, cp, sizeof(u_int32_t)); 1811 cp += sizeof(u_int32_t); 1812 1813 /* copy the address itself */ 1814 bcopy(&ifa6->ia_addr.sin6_addr, cp, 1815 sizeof(struct in6_addr)); 1816 in6_clearscope((struct in6_addr *)cp); /* XXX */ 1817 cp += sizeof(struct in6_addr); 1818 1819 resid -= (sizeof(struct in6_addr) + sizeof(u_int32_t)); 1820 copied += (sizeof(struct in6_addr) + sizeof(u_int32_t)); 1821 } 1822 if (ifp0) /* we need search only on the specified IF */ 1823 break; 1824 } 1825 1826 if (allow_deprecated == 0 && ifp_dep != NULL) { 1827 ifp = ifp_dep; 1828 allow_deprecated = 1; 1829 1830 goto again; 1831 } 1832 1833 return (copied); 1834 } 1835 1836 /* 1837 * XXX almost dup'ed code with rip6_input. 1838 */ 1839 static int 1840 icmp6_rip6_input(struct mbuf **mp, int off) 1841 { 1842 struct mbuf *m = *mp; 1843 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1844 struct inpcb_hdr *inph; 1845 struct in6pcb *in6p; 1846 struct in6pcb *last = NULL; 1847 struct sockaddr_in6 rip6src; 1848 struct icmp6_hdr *icmp6; 1849 struct mbuf *opts = NULL; 1850 1851 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 1852 if (icmp6 == NULL) { 1853 /* m is already reclaimed */ 1854 return IPPROTO_DONE; 1855 } 1856 1857 /* 1858 * XXX: the address may have embedded scope zone ID, which should be 1859 * hidden from applications. 1860 */ 1861 sockaddr_in6_init(&rip6src, &ip6->ip6_src, 0, 0, 0); 1862 if (sa6_recoverscope(&rip6src)) { 1863 m_freem(m); 1864 return (IPPROTO_DONE); 1865 } 1866 1867 CIRCLEQ_FOREACH(inph, &raw6cbtable.inpt_queue, inph_queue) { 1868 in6p = (struct in6pcb *)inph; 1869 if (in6p->in6p_af != AF_INET6) 1870 continue; 1871 if (in6p->in6p_ip6.ip6_nxt != IPPROTO_ICMPV6) 1872 continue; 1873 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr) && 1874 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr, &ip6->ip6_dst)) 1875 continue; 1876 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr) && 1877 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr, &ip6->ip6_src)) 1878 continue; 1879 if (in6p->in6p_icmp6filt 1880 && ICMP6_FILTER_WILLBLOCK(icmp6->icmp6_type, 1881 in6p->in6p_icmp6filt)) 1882 continue; 1883 if (last) { 1884 struct mbuf *n; 1885 if ((n = m_copy(m, 0, (int)M_COPYALL)) != NULL) { 1886 if (last->in6p_flags & IN6P_CONTROLOPTS) 1887 ip6_savecontrol(last, &opts, ip6, n); 1888 /* strip intermediate headers */ 1889 m_adj(n, off); 1890 if (sbappendaddr(&last->in6p_socket->so_rcv, 1891 (struct sockaddr *)&rip6src, 1892 n, opts) == 0) { 1893 /* should notify about lost packet */ 1894 m_freem(n); 1895 if (opts) 1896 m_freem(opts); 1897 } else 1898 sorwakeup(last->in6p_socket); 1899 opts = NULL; 1900 } 1901 } 1902 last = in6p; 1903 } 1904 if (last) { 1905 if (last->in6p_flags & IN6P_CONTROLOPTS) 1906 ip6_savecontrol(last, &opts, ip6, m); 1907 /* strip intermediate headers */ 1908 m_adj(m, off); 1909 if (sbappendaddr(&last->in6p_socket->so_rcv, 1910 (struct sockaddr *)&rip6src, m, opts) == 0) { 1911 m_freem(m); 1912 if (opts) 1913 m_freem(opts); 1914 } else 1915 sorwakeup(last->in6p_socket); 1916 } else { 1917 m_freem(m); 1918 IP6_STATDEC(IP6_STAT_DELIVERED); 1919 } 1920 return IPPROTO_DONE; 1921 } 1922 1923 /* 1924 * Reflect the ip6 packet back to the source. 1925 * OFF points to the icmp6 header, counted from the top of the mbuf. 1926 * 1927 * Note: RFC 1885 required that an echo reply should be truncated if it 1928 * did not fit in with (return) path MTU, and KAME code supported the 1929 * behavior. However, as a clarification after the RFC, this limitation 1930 * was removed in a revised version of the spec, RFC 2463. We had kept the 1931 * old behavior, with a (non-default) ifdef block, while the new version of 1932 * the spec was an internet-draft status, and even after the new RFC was 1933 * published. But it would rather make sense to clean the obsoleted part 1934 * up, and to make the code simpler at this stage. 1935 */ 1936 void 1937 icmp6_reflect(struct mbuf *m, size_t off) 1938 { 1939 struct ip6_hdr *ip6; 1940 struct icmp6_hdr *icmp6; 1941 const struct in6_ifaddr *ia; 1942 const struct ip6aux *ip6a; 1943 int plen; 1944 int type, code; 1945 struct ifnet *outif = NULL; 1946 struct in6_addr origdst; 1947 const struct in6_addr *src = NULL; 1948 1949 /* too short to reflect */ 1950 if (off < sizeof(struct ip6_hdr)) { 1951 nd6log((LOG_DEBUG, 1952 "sanity fail: off=%lx, sizeof(ip6)=%lx in %s:%d\n", 1953 (u_long)off, (u_long)sizeof(struct ip6_hdr), 1954 __FILE__, __LINE__)); 1955 goto bad; 1956 } 1957 1958 /* 1959 * If there are extra headers between IPv6 and ICMPv6, strip 1960 * off that header first. 1961 */ 1962 #ifdef DIAGNOSTIC 1963 if (sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) > MHLEN) 1964 panic("assumption failed in icmp6_reflect"); 1965 #endif 1966 if (off > sizeof(struct ip6_hdr)) { 1967 size_t l; 1968 struct ip6_hdr nip6; 1969 1970 l = off - sizeof(struct ip6_hdr); 1971 m_copydata(m, 0, sizeof(nip6), (void *)&nip6); 1972 m_adj(m, l); 1973 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 1974 if (m->m_len < l) { 1975 if ((m = m_pullup(m, l)) == NULL) 1976 return; 1977 } 1978 bcopy((void *)&nip6, mtod(m, void *), sizeof(nip6)); 1979 } else /* off == sizeof(struct ip6_hdr) */ { 1980 size_t l; 1981 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 1982 if (m->m_len < l) { 1983 if ((m = m_pullup(m, l)) == NULL) 1984 return; 1985 } 1986 } 1987 plen = m->m_pkthdr.len - sizeof(struct ip6_hdr); 1988 ip6 = mtod(m, struct ip6_hdr *); 1989 ip6->ip6_nxt = IPPROTO_ICMPV6; 1990 icmp6 = (struct icmp6_hdr *)(ip6 + 1); 1991 type = icmp6->icmp6_type; /* keep type for statistics */ 1992 code = icmp6->icmp6_code; /* ditto. */ 1993 1994 origdst = ip6->ip6_dst; 1995 /* 1996 * ip6_input() drops a packet if its src is multicast. 1997 * So, the src is never multicast. 1998 */ 1999 ip6->ip6_dst = ip6->ip6_src; 2000 2001 /* 2002 * If the incoming packet was addressed directly to us (i.e. unicast), 2003 * use dst as the src for the reply. 2004 * The IN6_IFF_NOTREADY case should be VERY rare, but is possible 2005 * (for example) when we encounter an error while forwarding procedure 2006 * destined to a duplicated address of ours. 2007 * Note that ip6_getdstifaddr() may fail if we are in an error handling 2008 * procedure of an outgoing packet of our own, in which case we need 2009 * to search in the ifaddr list. 2010 */ 2011 if (IN6_IS_ADDR_MULTICAST(&origdst)) 2012 ; 2013 else if ((ip6a = ip6_getdstifaddr(m)) != NULL) { 2014 if ((ip6a->ip6a_flags & 2015 (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY)) == 0) 2016 src = &ip6a->ip6a_src; 2017 } else { 2018 union { 2019 struct sockaddr_in6 sin6; 2020 struct sockaddr sa; 2021 } u; 2022 2023 sockaddr_in6_init(&u.sin6, &origdst, 0, 0, 0); 2024 2025 ia = (struct in6_ifaddr *)ifa_ifwithaddr(&u.sa); 2026 2027 if (ia == NULL) 2028 ; 2029 else if ((ia->ia6_flags & 2030 (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY)) == 0) 2031 src = &ia->ia_addr.sin6_addr; 2032 } 2033 2034 if (src == NULL) { 2035 int e; 2036 struct sockaddr_in6 sin6; 2037 struct route ro; 2038 2039 /* 2040 * This case matches to multicasts, our anycast, or unicasts 2041 * that we do not own. Select a source address based on the 2042 * source address of the erroneous packet. 2043 */ 2044 /* zone ID should be embedded */ 2045 sockaddr_in6_init(&sin6, &ip6->ip6_dst, 0, 0, 0); 2046 2047 memset(&ro, 0, sizeof(ro)); 2048 src = in6_selectsrc(&sin6, NULL, NULL, &ro, NULL, &outif, &e); 2049 rtcache_free(&ro); 2050 if (src == NULL) { 2051 nd6log((LOG_DEBUG, 2052 "icmp6_reflect: source can't be determined: " 2053 "dst=%s, error=%d\n", 2054 ip6_sprintf(&sin6.sin6_addr), e)); 2055 goto bad; 2056 } 2057 } 2058 2059 ip6->ip6_src = *src; 2060 ip6->ip6_flow = 0; 2061 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2062 ip6->ip6_vfc |= IPV6_VERSION; 2063 ip6->ip6_nxt = IPPROTO_ICMPV6; 2064 if (m->m_pkthdr.rcvif) { 2065 /* XXX: This may not be the outgoing interface */ 2066 ip6->ip6_hlim = ND_IFINFO(m->m_pkthdr.rcvif)->chlim; 2067 } else 2068 ip6->ip6_hlim = ip6_defhlim; 2069 2070 m->m_pkthdr.csum_flags = 0; 2071 icmp6->icmp6_cksum = 0; 2072 icmp6->icmp6_cksum = in6_cksum(m, IPPROTO_ICMPV6, 2073 sizeof(struct ip6_hdr), plen); 2074 2075 /* 2076 * XXX option handling 2077 */ 2078 2079 m->m_flags &= ~(M_BCAST|M_MCAST); 2080 2081 /* 2082 * To avoid a "too big" situation at an intermediate router 2083 * and the path MTU discovery process, specify the IPV6_MINMTU flag. 2084 * Note that only echo and node information replies are affected, 2085 * since the length of ICMP6 errors is limited to the minimum MTU. 2086 */ 2087 if (ip6_output(m, NULL, NULL, IPV6_MINMTU, NULL, NULL, &outif) != 0 && 2088 outif) 2089 icmp6_ifstat_inc(outif, ifs6_out_error); 2090 2091 if (outif) 2092 icmp6_ifoutstat_inc(outif, type, code); 2093 2094 return; 2095 2096 bad: 2097 m_freem(m); 2098 return; 2099 } 2100 2101 static const char * 2102 icmp6_redirect_diag(struct in6_addr *src6, struct in6_addr *dst6, 2103 struct in6_addr *tgt6) 2104 { 2105 static char buf[1024]; 2106 snprintf(buf, sizeof(buf), "(src=%s dst=%s tgt=%s)", 2107 ip6_sprintf(src6), ip6_sprintf(dst6), ip6_sprintf(tgt6)); 2108 return buf; 2109 } 2110 2111 void 2112 icmp6_redirect_input(struct mbuf *m, int off) 2113 { 2114 struct ifnet *ifp = m->m_pkthdr.rcvif; 2115 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 2116 struct nd_redirect *nd_rd; 2117 int icmp6len = ntohs(ip6->ip6_plen); 2118 char *lladdr = NULL; 2119 int lladdrlen = 0; 2120 struct rtentry *rt = NULL; 2121 int is_router; 2122 int is_onlink; 2123 struct in6_addr src6 = ip6->ip6_src; 2124 struct in6_addr redtgt6; 2125 struct in6_addr reddst6; 2126 union nd_opts ndopts; 2127 2128 if (!ifp) 2129 return; 2130 2131 /* XXX if we are router, we don't update route by icmp6 redirect */ 2132 if (ip6_forwarding) 2133 goto freeit; 2134 if (!icmp6_rediraccept) 2135 goto freeit; 2136 2137 IP6_EXTHDR_GET(nd_rd, struct nd_redirect *, m, off, icmp6len); 2138 if (nd_rd == NULL) { 2139 ICMP6_STATINC(ICMP6_STAT_TOOSHORT); 2140 return; 2141 } 2142 redtgt6 = nd_rd->nd_rd_target; 2143 reddst6 = nd_rd->nd_rd_dst; 2144 2145 if (in6_setscope(&redtgt6, m->m_pkthdr.rcvif, NULL) || 2146 in6_setscope(&reddst6, m->m_pkthdr.rcvif, NULL)) { 2147 goto freeit; 2148 } 2149 2150 /* validation */ 2151 if (!IN6_IS_ADDR_LINKLOCAL(&src6)) { 2152 nd6log((LOG_ERR, 2153 "ICMP6 redirect sent from %s rejected; " 2154 "must be from linklocal\n", ip6_sprintf(&src6))); 2155 goto bad; 2156 } 2157 if (ip6->ip6_hlim != 255) { 2158 nd6log((LOG_ERR, 2159 "ICMP6 redirect sent from %s rejected; " 2160 "hlim=%d (must be 255)\n", 2161 ip6_sprintf(&src6), ip6->ip6_hlim)); 2162 goto bad; 2163 } 2164 { 2165 /* ip6->ip6_src must be equal to gw for icmp6->icmp6_reddst */ 2166 struct sockaddr_in6 sin6; 2167 struct in6_addr *gw6; 2168 2169 sockaddr_in6_init(&sin6, &reddst6, 0, 0, 0); 2170 rt = rtalloc1((struct sockaddr *)&sin6, 0); 2171 if (rt) { 2172 if (rt->rt_gateway == NULL || 2173 rt->rt_gateway->sa_family != AF_INET6) { 2174 nd6log((LOG_ERR, 2175 "ICMP6 redirect rejected; no route " 2176 "with inet6 gateway found for redirect dst: %s\n", 2177 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2178 RTFREE(rt); 2179 goto bad; 2180 } 2181 2182 gw6 = &(((struct sockaddr_in6 *)rt->rt_gateway)->sin6_addr); 2183 if (bcmp(&src6, gw6, sizeof(struct in6_addr)) != 0) { 2184 nd6log((LOG_ERR, 2185 "ICMP6 redirect rejected; " 2186 "not equal to gw-for-src=%s (must be same): " 2187 "%s\n", 2188 ip6_sprintf(gw6), 2189 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2190 RTFREE(rt); 2191 goto bad; 2192 } 2193 } else { 2194 nd6log((LOG_ERR, 2195 "ICMP6 redirect rejected; " 2196 "no route found for redirect dst: %s\n", 2197 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2198 goto bad; 2199 } 2200 RTFREE(rt); 2201 rt = NULL; 2202 } 2203 if (IN6_IS_ADDR_MULTICAST(&reddst6)) { 2204 nd6log((LOG_ERR, 2205 "ICMP6 redirect rejected; " 2206 "redirect dst must be unicast: %s\n", 2207 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2208 goto bad; 2209 } 2210 2211 is_router = is_onlink = 0; 2212 if (IN6_IS_ADDR_LINKLOCAL(&redtgt6)) 2213 is_router = 1; /* router case */ 2214 if (bcmp(&redtgt6, &reddst6, sizeof(redtgt6)) == 0) 2215 is_onlink = 1; /* on-link destination case */ 2216 if (!is_router && !is_onlink) { 2217 nd6log((LOG_ERR, 2218 "ICMP6 redirect rejected; " 2219 "neither router case nor onlink case: %s\n", 2220 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2221 goto bad; 2222 } 2223 /* validation passed */ 2224 2225 icmp6len -= sizeof(*nd_rd); 2226 nd6_option_init(nd_rd + 1, icmp6len, &ndopts); 2227 if (nd6_options(&ndopts) < 0) { 2228 nd6log((LOG_INFO, "icmp6_redirect_input: " 2229 "invalid ND option, rejected: %s\n", 2230 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2231 /* nd6_options have incremented stats */ 2232 goto freeit; 2233 } 2234 2235 if (ndopts.nd_opts_tgt_lladdr) { 2236 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 2237 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 2238 } 2239 2240 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 2241 nd6log((LOG_INFO, 2242 "icmp6_redirect_input: lladdrlen mismatch for %s " 2243 "(if %d, icmp6 packet %d): %s\n", 2244 ip6_sprintf(&redtgt6), ifp->if_addrlen, lladdrlen - 2, 2245 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2246 goto bad; 2247 } 2248 2249 /* RFC 2461 8.3 */ 2250 nd6_cache_lladdr(ifp, &redtgt6, lladdr, lladdrlen, ND_REDIRECT, 2251 is_onlink ? ND_REDIRECT_ONLINK : ND_REDIRECT_ROUTER); 2252 2253 if (!is_onlink) { /* better router case. perform rtredirect. */ 2254 /* perform rtredirect */ 2255 struct sockaddr_in6 sdst; 2256 struct sockaddr_in6 sgw; 2257 struct sockaddr_in6 ssrc; 2258 unsigned long rtcount; 2259 struct rtentry *newrt = NULL; 2260 2261 /* 2262 * do not install redirect route, if the number of entries 2263 * is too much (> hiwat). note that, the node (= host) will 2264 * work just fine even if we do not install redirect route 2265 * (there will be additional hops, though). 2266 */ 2267 rtcount = rt_timer_count(icmp6_redirect_timeout_q); 2268 if (0 <= icmp6_redirect_hiwat && rtcount > icmp6_redirect_hiwat) 2269 return; 2270 else if (0 <= icmp6_redirect_lowat && 2271 rtcount > icmp6_redirect_lowat) { 2272 /* 2273 * XXX nuke a victim, install the new one. 2274 */ 2275 } 2276 2277 bzero(&sdst, sizeof(sdst)); 2278 bzero(&sgw, sizeof(sgw)); 2279 bzero(&ssrc, sizeof(ssrc)); 2280 sdst.sin6_family = sgw.sin6_family = ssrc.sin6_family = AF_INET6; 2281 sdst.sin6_len = sgw.sin6_len = ssrc.sin6_len = 2282 sizeof(struct sockaddr_in6); 2283 bcopy(&redtgt6, &sgw.sin6_addr, sizeof(struct in6_addr)); 2284 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2285 bcopy(&src6, &ssrc.sin6_addr, sizeof(struct in6_addr)); 2286 rtredirect((struct sockaddr *)&sdst, (struct sockaddr *)&sgw, 2287 (struct sockaddr *)NULL, RTF_GATEWAY | RTF_HOST, 2288 (struct sockaddr *)&ssrc, 2289 &newrt); 2290 2291 if (newrt) { 2292 (void)rt_timer_add(newrt, icmp6_redirect_timeout, 2293 icmp6_redirect_timeout_q); 2294 rtfree(newrt); 2295 } 2296 } 2297 /* finally update cached route in each socket via pfctlinput */ 2298 { 2299 struct sockaddr_in6 sdst; 2300 2301 sockaddr_in6_init(&sdst, &reddst6, 0, 0, 0); 2302 pfctlinput(PRC_REDIRECT_HOST, (struct sockaddr *)&sdst); 2303 #if defined(IPSEC) || defined(FAST_IPSEC) 2304 key_sa_routechange((struct sockaddr *)&sdst); 2305 #endif 2306 } 2307 2308 freeit: 2309 m_freem(m); 2310 return; 2311 2312 bad: 2313 ICMP6_STATINC(ICMP6_STAT_BADREDIRECT); 2314 m_freem(m); 2315 } 2316 2317 void 2318 icmp6_redirect_output(struct mbuf *m0, struct rtentry *rt) 2319 { 2320 struct ifnet *ifp; /* my outgoing interface */ 2321 struct in6_addr *ifp_ll6; 2322 struct in6_addr *nexthop; 2323 struct ip6_hdr *sip6; /* m0 as struct ip6_hdr */ 2324 struct mbuf *m = NULL; /* newly allocated one */ 2325 struct ip6_hdr *ip6; /* m as struct ip6_hdr */ 2326 struct nd_redirect *nd_rd; 2327 size_t maxlen; 2328 u_char *p; 2329 struct sockaddr_in6 src_sa; 2330 2331 icmp6_errcount(ICMP6_STAT_OUTERRHIST, ND_REDIRECT, 0); 2332 2333 /* if we are not router, we don't send icmp6 redirect */ 2334 if (!ip6_forwarding) 2335 goto fail; 2336 2337 /* sanity check */ 2338 if (!m0 || !rt || !(rt->rt_flags & RTF_UP) || !(ifp = rt->rt_ifp)) 2339 goto fail; 2340 2341 /* 2342 * Address check: 2343 * the source address must identify a neighbor, and 2344 * the destination address must not be a multicast address 2345 * [RFC 2461, sec 8.2] 2346 */ 2347 sip6 = mtod(m0, struct ip6_hdr *); 2348 sockaddr_in6_init(&src_sa, &sip6->ip6_src, 0, 0, 0); 2349 if (nd6_is_addr_neighbor(&src_sa, ifp) == 0) 2350 goto fail; 2351 if (IN6_IS_ADDR_MULTICAST(&sip6->ip6_dst)) 2352 goto fail; /* what should we do here? */ 2353 2354 /* rate limit */ 2355 if (icmp6_ratelimit(&sip6->ip6_src, ND_REDIRECT, 0)) 2356 goto fail; 2357 2358 /* 2359 * Since we are going to append up to 1280 bytes (= IPV6_MMTU), 2360 * we almost always ask for an mbuf cluster for simplicity. 2361 * (MHLEN < IPV6_MMTU is almost always true) 2362 */ 2363 #if IPV6_MMTU >= MCLBYTES 2364 # error assumption failed about IPV6_MMTU and MCLBYTES 2365 #endif 2366 MGETHDR(m, M_DONTWAIT, MT_HEADER); 2367 if (m && IPV6_MMTU >= MHLEN) 2368 MCLGET(m, M_DONTWAIT); 2369 if (!m) 2370 goto fail; 2371 m->m_pkthdr.rcvif = NULL; 2372 m->m_len = 0; 2373 maxlen = M_TRAILINGSPACE(m); 2374 maxlen = min(IPV6_MMTU, maxlen); 2375 /* just for safety */ 2376 if (maxlen < sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) + 2377 ((sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7)) { 2378 goto fail; 2379 } 2380 2381 { 2382 /* get ip6 linklocal address for ifp(my outgoing interface). */ 2383 struct in6_ifaddr *ia; 2384 if ((ia = in6ifa_ifpforlinklocal(ifp, 2385 IN6_IFF_NOTREADY| 2386 IN6_IFF_ANYCAST)) == NULL) 2387 goto fail; 2388 ifp_ll6 = &ia->ia_addr.sin6_addr; 2389 } 2390 2391 /* get ip6 linklocal address for the router. */ 2392 if (rt->rt_gateway && (rt->rt_flags & RTF_GATEWAY)) { 2393 struct sockaddr_in6 *sin6; 2394 sin6 = (struct sockaddr_in6 *)rt->rt_gateway; 2395 nexthop = &sin6->sin6_addr; 2396 if (!IN6_IS_ADDR_LINKLOCAL(nexthop)) 2397 nexthop = NULL; 2398 } else 2399 nexthop = NULL; 2400 2401 /* ip6 */ 2402 ip6 = mtod(m, struct ip6_hdr *); 2403 ip6->ip6_flow = 0; 2404 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2405 ip6->ip6_vfc |= IPV6_VERSION; 2406 /* ip6->ip6_plen will be set later */ 2407 ip6->ip6_nxt = IPPROTO_ICMPV6; 2408 ip6->ip6_hlim = 255; 2409 /* ip6->ip6_src must be linklocal addr for my outgoing if. */ 2410 bcopy(ifp_ll6, &ip6->ip6_src, sizeof(struct in6_addr)); 2411 bcopy(&sip6->ip6_src, &ip6->ip6_dst, sizeof(struct in6_addr)); 2412 2413 /* ND Redirect */ 2414 nd_rd = (struct nd_redirect *)(ip6 + 1); 2415 nd_rd->nd_rd_type = ND_REDIRECT; 2416 nd_rd->nd_rd_code = 0; 2417 nd_rd->nd_rd_reserved = 0; 2418 if (rt->rt_flags & RTF_GATEWAY) { 2419 /* 2420 * nd_rd->nd_rd_target must be a link-local address in 2421 * better router cases. 2422 */ 2423 if (!nexthop) 2424 goto fail; 2425 bcopy(nexthop, &nd_rd->nd_rd_target, 2426 sizeof(nd_rd->nd_rd_target)); 2427 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2428 sizeof(nd_rd->nd_rd_dst)); 2429 } else { 2430 /* make sure redtgt == reddst */ 2431 nexthop = &sip6->ip6_dst; 2432 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_target, 2433 sizeof(nd_rd->nd_rd_target)); 2434 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2435 sizeof(nd_rd->nd_rd_dst)); 2436 } 2437 2438 p = (u_char *)(nd_rd + 1); 2439 2440 { 2441 /* target lladdr option */ 2442 struct rtentry *rt_nexthop = NULL; 2443 int len; 2444 const struct sockaddr_dl *sdl; 2445 struct nd_opt_hdr *nd_opt; 2446 char *lladdr; 2447 2448 rt_nexthop = nd6_lookup(nexthop, 0, ifp); 2449 if (!rt_nexthop) 2450 goto nolladdropt; 2451 len = sizeof(*nd_opt) + ifp->if_addrlen; 2452 len = (len + 7) & ~7; /* round by 8 */ 2453 /* safety check */ 2454 if (len + (p - (u_char *)ip6) > maxlen) 2455 goto nolladdropt; 2456 if (!(rt_nexthop->rt_flags & RTF_GATEWAY) && 2457 (rt_nexthop->rt_flags & RTF_LLINFO) && 2458 (rt_nexthop->rt_gateway->sa_family == AF_LINK) && 2459 (sdl = satocsdl(rt_nexthop->rt_gateway)) && 2460 sdl->sdl_alen) { 2461 nd_opt = (struct nd_opt_hdr *)p; 2462 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 2463 nd_opt->nd_opt_len = len >> 3; 2464 lladdr = (char *)(nd_opt + 1); 2465 memcpy(lladdr, CLLADDR(sdl), ifp->if_addrlen); 2466 p += len; 2467 } 2468 } 2469 nolladdropt:; 2470 2471 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2472 2473 /* just to be safe */ 2474 if (m0->m_flags & M_DECRYPTED) 2475 goto noredhdropt; 2476 if (p - (u_char *)ip6 > maxlen) 2477 goto noredhdropt; 2478 2479 { 2480 /* redirected header option */ 2481 int len; 2482 struct nd_opt_rd_hdr *nd_opt_rh; 2483 2484 /* 2485 * compute the maximum size for icmp6 redirect header option. 2486 * XXX room for auth header? 2487 */ 2488 len = maxlen - (p - (u_char *)ip6); 2489 len &= ~7; 2490 2491 /* 2492 * Redirected header option spec (RFC2461 4.6.3) talks nothing 2493 * about padding/truncate rule for the original IP packet. 2494 * From the discussion on IPv6imp in Feb 1999, 2495 * the consensus was: 2496 * - "attach as much as possible" is the goal 2497 * - pad if not aligned (original size can be guessed by 2498 * original ip6 header) 2499 * Following code adds the padding if it is simple enough, 2500 * and truncates if not. 2501 */ 2502 if (len - sizeof(*nd_opt_rh) < m0->m_pkthdr.len) { 2503 /* not enough room, truncate */ 2504 m_adj(m0, (len - sizeof(*nd_opt_rh)) - 2505 m0->m_pkthdr.len); 2506 } else { 2507 /* 2508 * enough room, truncate if not aligned. 2509 * we don't pad here for simplicity. 2510 */ 2511 size_t extra; 2512 2513 extra = m0->m_pkthdr.len % 8; 2514 if (extra) { 2515 /* truncate */ 2516 m_adj(m0, -extra); 2517 } 2518 len = m0->m_pkthdr.len + sizeof(*nd_opt_rh); 2519 } 2520 2521 nd_opt_rh = (struct nd_opt_rd_hdr *)p; 2522 bzero(nd_opt_rh, sizeof(*nd_opt_rh)); 2523 nd_opt_rh->nd_opt_rh_type = ND_OPT_REDIRECTED_HEADER; 2524 nd_opt_rh->nd_opt_rh_len = len >> 3; 2525 p += sizeof(*nd_opt_rh); 2526 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2527 2528 /* connect m0 to m */ 2529 m->m_pkthdr.len += m0->m_pkthdr.len; 2530 m_cat(m, m0); 2531 m0 = NULL; 2532 } 2533 noredhdropt: 2534 if (m0) { 2535 m_freem(m0); 2536 m0 = NULL; 2537 } 2538 2539 /* XXX: clear embedded link IDs in the inner header */ 2540 in6_clearscope(&sip6->ip6_src); 2541 in6_clearscope(&sip6->ip6_dst); 2542 in6_clearscope(&nd_rd->nd_rd_target); 2543 in6_clearscope(&nd_rd->nd_rd_dst); 2544 2545 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr)); 2546 2547 nd_rd->nd_rd_cksum = 0; 2548 nd_rd->nd_rd_cksum 2549 = in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), ntohs(ip6->ip6_plen)); 2550 2551 /* send the packet to outside... */ 2552 if (ip6_output(m, NULL, NULL, 0, 2553 (struct ip6_moptions *)NULL, (struct socket *)NULL, NULL) != 0) 2554 icmp6_ifstat_inc(ifp, ifs6_out_error); 2555 2556 icmp6_ifstat_inc(ifp, ifs6_out_msg); 2557 icmp6_ifstat_inc(ifp, ifs6_out_redirect); 2558 ICMP6_STATINC(ICMP6_STAT_OUTHIST + ND_REDIRECT); 2559 2560 return; 2561 2562 fail: 2563 if (m) 2564 m_freem(m); 2565 if (m0) 2566 m_freem(m0); 2567 } 2568 2569 /* 2570 * ICMPv6 socket option processing. 2571 */ 2572 int 2573 icmp6_ctloutput(int op, struct socket *so, int level, 2574 int optname, struct mbuf **mp) 2575 { 2576 int error = 0; 2577 int optlen; 2578 struct in6pcb *in6p = sotoin6pcb(so); 2579 struct mbuf *m = *mp; 2580 2581 optlen = m ? m->m_len : 0; 2582 2583 if (level != IPPROTO_ICMPV6) 2584 return rip6_ctloutput(op, so, level, optname, mp); 2585 2586 switch (op) { 2587 case PRCO_SETOPT: 2588 switch (optname) { 2589 case ICMP6_FILTER: 2590 { 2591 struct icmp6_filter *p; 2592 2593 if (optlen != sizeof(*p)) { 2594 error = EMSGSIZE; 2595 break; 2596 } 2597 p = mtod(m, struct icmp6_filter *); 2598 if (!p || !in6p->in6p_icmp6filt) { 2599 error = EINVAL; 2600 break; 2601 } 2602 bcopy(p, in6p->in6p_icmp6filt, 2603 sizeof(struct icmp6_filter)); 2604 error = 0; 2605 break; 2606 } 2607 2608 default: 2609 error = ENOPROTOOPT; 2610 break; 2611 } 2612 if (m) 2613 (void)m_freem(m); 2614 break; 2615 2616 case PRCO_GETOPT: 2617 switch (optname) { 2618 case ICMP6_FILTER: 2619 { 2620 struct icmp6_filter *p; 2621 2622 if (!in6p->in6p_icmp6filt) { 2623 error = EINVAL; 2624 break; 2625 } 2626 *mp = m = m_get(M_WAIT, MT_SOOPTS); 2627 m->m_len = sizeof(struct icmp6_filter); 2628 p = mtod(m, struct icmp6_filter *); 2629 bcopy(in6p->in6p_icmp6filt, p, 2630 sizeof(struct icmp6_filter)); 2631 error = 0; 2632 break; 2633 } 2634 2635 default: 2636 error = ENOPROTOOPT; 2637 break; 2638 } 2639 break; 2640 } 2641 2642 return (error); 2643 } 2644 2645 /* 2646 * Perform rate limit check. 2647 * Returns 0 if it is okay to send the icmp6 packet. 2648 * Returns 1 if the router SHOULD NOT send this icmp6 packet due to rate 2649 * limitation. 2650 * 2651 * XXX per-destination/type check necessary? 2652 */ 2653 static int 2654 icmp6_ratelimit( 2655 const struct in6_addr *dst, /* not used at this moment */ 2656 const int type, /* not used at this moment */ 2657 const int code) /* not used at this moment */ 2658 { 2659 int ret; 2660 2661 ret = 0; /* okay to send */ 2662 2663 /* PPS limit */ 2664 if (!ppsratecheck(&icmp6errppslim_last, &icmp6errpps_count, 2665 icmp6errppslim)) { 2666 /* The packet is subject to rate limit */ 2667 ret++; 2668 } 2669 2670 return ret; 2671 } 2672 2673 static struct rtentry * 2674 icmp6_mtudisc_clone(struct sockaddr *dst) 2675 { 2676 struct rtentry *rt; 2677 int error; 2678 2679 rt = rtalloc1(dst, 1); 2680 if (rt == 0) 2681 return NULL; 2682 2683 /* If we didn't get a host route, allocate one */ 2684 if ((rt->rt_flags & RTF_HOST) == 0) { 2685 struct rtentry *nrt; 2686 2687 error = rtrequest((int) RTM_ADD, dst, 2688 (struct sockaddr *) rt->rt_gateway, 2689 (struct sockaddr *) 0, 2690 RTF_GATEWAY | RTF_HOST | RTF_DYNAMIC, &nrt); 2691 if (error) { 2692 rtfree(rt); 2693 return NULL; 2694 } 2695 nrt->rt_rmx = rt->rt_rmx; 2696 rtfree(rt); 2697 rt = nrt; 2698 } 2699 error = rt_timer_add(rt, icmp6_mtudisc_timeout, 2700 icmp6_mtudisc_timeout_q); 2701 if (error) { 2702 rtfree(rt); 2703 return NULL; 2704 } 2705 2706 return rt; /* caller need to call rtfree() */ 2707 } 2708 2709 static void 2710 icmp6_mtudisc_timeout(struct rtentry *rt, struct rttimer *r) 2711 { 2712 if (rt == NULL) 2713 panic("icmp6_mtudisc_timeout: bad route to timeout"); 2714 if ((rt->rt_flags & (RTF_DYNAMIC | RTF_HOST)) == 2715 (RTF_DYNAMIC | RTF_HOST)) { 2716 rtrequest((int) RTM_DELETE, rt_getkey(rt), 2717 rt->rt_gateway, rt_mask(rt), rt->rt_flags, 0); 2718 } else { 2719 if (!(rt->rt_rmx.rmx_locks & RTV_MTU)) 2720 rt->rt_rmx.rmx_mtu = 0; 2721 } 2722 } 2723 2724 static void 2725 icmp6_redirect_timeout(struct rtentry *rt, struct rttimer *r) 2726 { 2727 if (rt == NULL) 2728 panic("icmp6_redirect_timeout: bad route to timeout"); 2729 if ((rt->rt_flags & (RTF_GATEWAY | RTF_DYNAMIC | RTF_HOST)) == 2730 (RTF_GATEWAY | RTF_DYNAMIC | RTF_HOST)) { 2731 rtrequest((int) RTM_DELETE, rt_getkey(rt), 2732 rt->rt_gateway, rt_mask(rt), rt->rt_flags, 0); 2733 } 2734 } 2735 2736 /* 2737 * sysctl helper routine for the net.inet6.icmp6.nd6 nodes. silly? 2738 */ 2739 static int 2740 sysctl_net_inet6_icmp6_nd6(SYSCTLFN_ARGS) 2741 { 2742 (void)&name; 2743 (void)&l; 2744 (void)&oname; 2745 2746 if (namelen != 0) 2747 return (EINVAL); 2748 2749 return (nd6_sysctl(rnode->sysctl_num, oldp, oldlenp, 2750 /*XXXUNCONST*/ 2751 __UNCONST(newp), newlen)); 2752 } 2753 2754 static int 2755 sysctl_net_inet6_icmp6_stats(SYSCTLFN_ARGS) 2756 { 2757 2758 return (NETSTAT_SYSCTL(icmp6stat_percpu, ICMP6_NSTATS)); 2759 } 2760 2761 SYSCTL_SETUP(sysctl_net_inet6_icmp6_setup, 2762 "sysctl net.inet6.icmp6 subtree setup") 2763 { 2764 extern int nd6_maxqueuelen; /* defined in nd6.c */ 2765 2766 sysctl_createv(clog, 0, NULL, NULL, 2767 CTLFLAG_PERMANENT, 2768 CTLTYPE_NODE, "net", NULL, 2769 NULL, 0, NULL, 0, 2770 CTL_NET, CTL_EOL); 2771 sysctl_createv(clog, 0, NULL, NULL, 2772 CTLFLAG_PERMANENT, 2773 CTLTYPE_NODE, "inet6", NULL, 2774 NULL, 0, NULL, 0, 2775 CTL_NET, PF_INET6, CTL_EOL); 2776 sysctl_createv(clog, 0, NULL, NULL, 2777 CTLFLAG_PERMANENT, 2778 CTLTYPE_NODE, "icmp6", 2779 SYSCTL_DESCR("ICMPv6 related settings"), 2780 NULL, 0, NULL, 0, 2781 CTL_NET, PF_INET6, IPPROTO_ICMPV6, CTL_EOL); 2782 2783 sysctl_createv(clog, 0, NULL, NULL, 2784 CTLFLAG_PERMANENT, 2785 CTLTYPE_STRUCT, "stats", 2786 SYSCTL_DESCR("ICMPv6 transmission statistics"), 2787 sysctl_net_inet6_icmp6_stats, 0, NULL, 0, 2788 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2789 ICMPV6CTL_STATS, CTL_EOL); 2790 sysctl_createv(clog, 0, NULL, NULL, 2791 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2792 CTLTYPE_INT, "rediraccept", 2793 SYSCTL_DESCR("Accept and process redirect messages"), 2794 NULL, 0, &icmp6_rediraccept, 0, 2795 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2796 ICMPV6CTL_REDIRACCEPT, CTL_EOL); 2797 sysctl_createv(clog, 0, NULL, NULL, 2798 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2799 CTLTYPE_INT, "redirtimeout", 2800 SYSCTL_DESCR("Redirect generated route lifetime"), 2801 NULL, 0, &icmp6_redirtimeout, 0, 2802 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2803 ICMPV6CTL_REDIRTIMEOUT, CTL_EOL); 2804 #if 0 /* obsoleted */ 2805 sysctl_createv(clog, 0, NULL, NULL, 2806 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2807 CTLTYPE_INT, "errratelimit", NULL, 2808 NULL, 0, &icmp6_errratelimit, 0, 2809 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2810 ICMPV6CTL_ERRRATELIMIT, CTL_EOL); 2811 #endif 2812 sysctl_createv(clog, 0, NULL, NULL, 2813 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2814 CTLTYPE_INT, "nd6_prune", 2815 SYSCTL_DESCR("Neighbor discovery prune interval"), 2816 NULL, 0, &nd6_prune, 0, 2817 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2818 ICMPV6CTL_ND6_PRUNE, CTL_EOL); 2819 sysctl_createv(clog, 0, NULL, NULL, 2820 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2821 CTLTYPE_INT, "nd6_delay", 2822 SYSCTL_DESCR("First probe delay time"), 2823 NULL, 0, &nd6_delay, 0, 2824 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2825 ICMPV6CTL_ND6_DELAY, CTL_EOL); 2826 sysctl_createv(clog, 0, NULL, NULL, 2827 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2828 CTLTYPE_INT, "nd6_umaxtries", 2829 SYSCTL_DESCR("Number of unicast discovery attempts"), 2830 NULL, 0, &nd6_umaxtries, 0, 2831 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2832 ICMPV6CTL_ND6_UMAXTRIES, CTL_EOL); 2833 sysctl_createv(clog, 0, NULL, NULL, 2834 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2835 CTLTYPE_INT, "nd6_mmaxtries", 2836 SYSCTL_DESCR("Number of multicast discovery attempts"), 2837 NULL, 0, &nd6_mmaxtries, 0, 2838 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2839 ICMPV6CTL_ND6_MMAXTRIES, CTL_EOL); 2840 sysctl_createv(clog, 0, NULL, NULL, 2841 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2842 CTLTYPE_INT, "nd6_useloopback", 2843 SYSCTL_DESCR("Use loopback interface for local traffic"), 2844 NULL, 0, &nd6_useloopback, 0, 2845 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2846 ICMPV6CTL_ND6_USELOOPBACK, CTL_EOL); 2847 #if 0 /* obsoleted */ 2848 sysctl_createv(clog, 0, NULL, NULL, 2849 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2850 CTLTYPE_INT, "nd6_proxyall", NULL, 2851 NULL, 0, &nd6_proxyall, 0, 2852 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2853 ICMPV6CTL_ND6_PROXYALL, CTL_EOL); 2854 #endif 2855 sysctl_createv(clog, 0, NULL, NULL, 2856 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2857 CTLTYPE_INT, "nodeinfo", 2858 SYSCTL_DESCR("Respond to node information requests"), 2859 NULL, 0, &icmp6_nodeinfo, 0, 2860 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2861 ICMPV6CTL_NODEINFO, CTL_EOL); 2862 sysctl_createv(clog, 0, NULL, NULL, 2863 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2864 CTLTYPE_INT, "errppslimit", 2865 SYSCTL_DESCR("Maximum ICMP errors sent per second"), 2866 NULL, 0, &icmp6errppslim, 0, 2867 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2868 ICMPV6CTL_ERRPPSLIMIT, CTL_EOL); 2869 sysctl_createv(clog, 0, NULL, NULL, 2870 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2871 CTLTYPE_INT, "nd6_maxnudhint", 2872 SYSCTL_DESCR("Maximum neighbor unreachable hint count"), 2873 NULL, 0, &nd6_maxnudhint, 0, 2874 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2875 ICMPV6CTL_ND6_MAXNUDHINT, CTL_EOL); 2876 sysctl_createv(clog, 0, NULL, NULL, 2877 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2878 CTLTYPE_INT, "mtudisc_hiwat", 2879 SYSCTL_DESCR("Low mark on MTU Discovery route timers"), 2880 NULL, 0, &icmp6_mtudisc_hiwat, 0, 2881 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2882 ICMPV6CTL_MTUDISC_HIWAT, CTL_EOL); 2883 sysctl_createv(clog, 0, NULL, NULL, 2884 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2885 CTLTYPE_INT, "mtudisc_lowat", 2886 SYSCTL_DESCR("Low mark on MTU Discovery route timers"), 2887 NULL, 0, &icmp6_mtudisc_lowat, 0, 2888 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2889 ICMPV6CTL_MTUDISC_LOWAT, CTL_EOL); 2890 sysctl_createv(clog, 0, NULL, NULL, 2891 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2892 CTLTYPE_INT, "nd6_debug", 2893 SYSCTL_DESCR("Enable neighbor discovery debug output"), 2894 NULL, 0, &nd6_debug, 0, 2895 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2896 ICMPV6CTL_ND6_DEBUG, CTL_EOL); 2897 sysctl_createv(clog, 0, NULL, NULL, 2898 CTLFLAG_PERMANENT, 2899 CTLTYPE_STRUCT, "nd6_drlist", 2900 SYSCTL_DESCR("Default router list"), 2901 sysctl_net_inet6_icmp6_nd6, 0, NULL, 0, 2902 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2903 ICMPV6CTL_ND6_DRLIST, CTL_EOL); 2904 sysctl_createv(clog, 0, NULL, NULL, 2905 CTLFLAG_PERMANENT, 2906 CTLTYPE_STRUCT, "nd6_prlist", 2907 SYSCTL_DESCR("Prefix list"), 2908 sysctl_net_inet6_icmp6_nd6, 0, NULL, 0, 2909 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2910 ICMPV6CTL_ND6_PRLIST, CTL_EOL); 2911 sysctl_createv(clog, 0, NULL, NULL, 2912 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2913 CTLTYPE_INT, "maxqueuelen", 2914 SYSCTL_DESCR("max packet queue len for a unresolved ND"), 2915 NULL, 1, &nd6_maxqueuelen, 0, 2916 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2917 ICMPV6CTL_ND6_MAXQLEN, CTL_EOL); 2918 } 2919 2920 void 2921 icmp6_statinc(u_int stat) 2922 { 2923 2924 KASSERT(stat < ICMP6_NSTATS); 2925 ICMP6_STATINC(stat); 2926 } 2927