icmp6.c revision 1.155
1 /* $NetBSD: icmp6.c,v 1.155 2009/10/18 22:57:05 christos 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 1.155 2009/10/18 22:57:05 christos 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 static void sysctl_net_inet6_icmp6_setup(struct sysctllog **); 174 175 176 void 177 icmp6_init(void) 178 { 179 180 sysctl_net_inet6_icmp6_setup(NULL); 181 mld_init(); 182 icmp6_mtudisc_timeout_q = rt_timer_queue_create(pmtu_expire); 183 icmp6_redirect_timeout_q = rt_timer_queue_create(icmp6_redirtimeout); 184 185 icmp6stat_percpu = percpu_alloc(sizeof(uint64_t) * ICMP6_NSTATS); 186 } 187 188 static void 189 icmp6_errcount(u_int base, int type, int code) 190 { 191 switch (type) { 192 case ICMP6_DST_UNREACH: 193 switch (code) { 194 case ICMP6_DST_UNREACH_NOROUTE: 195 ICMP6_STATINC(base + ICMP6_ERRSTAT_DST_UNREACH_NOROUTE); 196 return; 197 case ICMP6_DST_UNREACH_ADMIN: 198 ICMP6_STATINC(base + ICMP6_ERRSTAT_DST_UNREACH_ADMIN); 199 return; 200 case ICMP6_DST_UNREACH_BEYONDSCOPE: 201 ICMP6_STATINC(base + 202 ICMP6_ERRSTAT_DST_UNREACH_BEYONDSCOPE); 203 return; 204 case ICMP6_DST_UNREACH_ADDR: 205 ICMP6_STATINC(base + ICMP6_ERRSTAT_DST_UNREACH_ADDR); 206 return; 207 case ICMP6_DST_UNREACH_NOPORT: 208 ICMP6_STATINC(base + ICMP6_ERRSTAT_DST_UNREACH_NOPORT); 209 return; 210 } 211 break; 212 case ICMP6_PACKET_TOO_BIG: 213 ICMP6_STATINC(base + ICMP6_ERRSTAT_PACKET_TOO_BIG); 214 return; 215 case ICMP6_TIME_EXCEEDED: 216 switch (code) { 217 case ICMP6_TIME_EXCEED_TRANSIT: 218 ICMP6_STATINC(base + ICMP6_ERRSTAT_TIME_EXCEED_TRANSIT); 219 return; 220 case ICMP6_TIME_EXCEED_REASSEMBLY: 221 ICMP6_STATINC(base + 222 ICMP6_ERRSTAT_TIME_EXCEED_REASSEMBLY); 223 return; 224 } 225 break; 226 case ICMP6_PARAM_PROB: 227 switch (code) { 228 case ICMP6_PARAMPROB_HEADER: 229 ICMP6_STATINC(base + ICMP6_ERRSTAT_PARAMPROB_HEADER); 230 return; 231 case ICMP6_PARAMPROB_NEXTHEADER: 232 ICMP6_STATINC(base + 233 ICMP6_ERRSTAT_PARAMPROB_NEXTHEADER); 234 return; 235 case ICMP6_PARAMPROB_OPTION: 236 ICMP6_STATINC(base + ICMP6_ERRSTAT_PARAMPROB_OPTION); 237 return; 238 } 239 break; 240 case ND_REDIRECT: 241 ICMP6_STATINC(base + ICMP6_ERRSTAT_REDIRECT); 242 return; 243 } 244 ICMP6_STATINC(base + ICMP6_ERRSTAT_UNKNOWN); 245 } 246 247 /* 248 * Register a Path MTU Discovery callback. 249 */ 250 void 251 icmp6_mtudisc_callback_register(void (*func)(struct in6_addr *)) 252 { 253 struct icmp6_mtudisc_callback *mc; 254 255 for (mc = LIST_FIRST(&icmp6_mtudisc_callbacks); mc != NULL; 256 mc = LIST_NEXT(mc, mc_list)) { 257 if (mc->mc_func == func) 258 return; 259 } 260 261 mc = malloc(sizeof(*mc), M_PCB, M_NOWAIT); 262 if (mc == NULL) 263 panic("icmp6_mtudisc_callback_register"); 264 265 mc->mc_func = func; 266 LIST_INSERT_HEAD(&icmp6_mtudisc_callbacks, mc, mc_list); 267 } 268 269 /* 270 * A wrapper function for icmp6_error() necessary when the erroneous packet 271 * may not contain enough scope zone information. 272 */ 273 void 274 icmp6_error2(struct mbuf *m, int type, int code, int param, 275 struct ifnet *ifp) 276 { 277 struct ip6_hdr *ip6; 278 279 if (ifp == NULL) 280 return; 281 282 if (m->m_len < sizeof(struct ip6_hdr)) { 283 m = m_pullup(m, sizeof(struct ip6_hdr)); 284 if (m == NULL) 285 return; 286 } 287 288 ip6 = mtod(m, struct ip6_hdr *); 289 290 if (in6_setscope(&ip6->ip6_src, ifp, NULL) != 0) 291 return; 292 if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0) 293 return; 294 295 icmp6_error(m, type, code, param); 296 } 297 298 /* 299 * Generate an error packet of type error in response to bad IP6 packet. 300 */ 301 void 302 icmp6_error(struct mbuf *m, int type, int code, int param) 303 { 304 struct ip6_hdr *oip6, *nip6; 305 struct icmp6_hdr *icmp6; 306 u_int preplen; 307 int off; 308 int nxt; 309 310 ICMP6_STATINC(ICMP6_STAT_ERROR); 311 312 /* count per-type-code statistics */ 313 icmp6_errcount(ICMP6_STAT_OUTERRHIST, type, code); 314 315 if (m->m_flags & M_DECRYPTED) { 316 ICMP6_STATINC(ICMP6_STAT_CANTERROR); 317 goto freeit; 318 } 319 320 if (M_UNWRITABLE(m, sizeof(struct ip6_hdr)) && 321 (m = m_pullup(m, sizeof(struct ip6_hdr))) == NULL) 322 return; 323 oip6 = mtod(m, struct ip6_hdr *); 324 325 /* 326 * If the destination address of the erroneous packet is a multicast 327 * address, or the packet was sent using link-layer multicast, 328 * we should basically suppress sending an error (RFC 2463, Section 329 * 2.4). 330 * We have two exceptions (the item e.2 in that section): 331 * - the Pakcet Too Big message can be sent for path MTU discovery. 332 * - the Parameter Problem Message that can be allowed an icmp6 error 333 * in the option type field. This check has been done in 334 * ip6_unknown_opt(), so we can just check the type and code. 335 */ 336 if ((m->m_flags & (M_BCAST|M_MCAST) || 337 IN6_IS_ADDR_MULTICAST(&oip6->ip6_dst)) && 338 (type != ICMP6_PACKET_TOO_BIG && 339 (type != ICMP6_PARAM_PROB || 340 code != ICMP6_PARAMPROB_OPTION))) 341 goto freeit; 342 343 /* 344 * RFC 2463, 2.4 (e.5): source address check. 345 * XXX: the case of anycast source? 346 */ 347 if (IN6_IS_ADDR_UNSPECIFIED(&oip6->ip6_src) || 348 IN6_IS_ADDR_MULTICAST(&oip6->ip6_src)) 349 goto freeit; 350 351 /* 352 * If we are about to send ICMPv6 against ICMPv6 error/redirect, 353 * don't do it. 354 */ 355 nxt = -1; 356 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); 357 if (off >= 0 && nxt == IPPROTO_ICMPV6) { 358 struct icmp6_hdr *icp; 359 360 IP6_EXTHDR_GET(icp, struct icmp6_hdr *, m, off, 361 sizeof(*icp)); 362 if (icp == NULL) { 363 ICMP6_STATINC(ICMP6_STAT_TOOSHORT); 364 return; 365 } 366 if (icp->icmp6_type < ICMP6_ECHO_REQUEST || 367 icp->icmp6_type == ND_REDIRECT) { 368 /* 369 * ICMPv6 error 370 * Special case: for redirect (which is 371 * informational) we must not send icmp6 error. 372 */ 373 ICMP6_STATINC(ICMP6_STAT_CANTERROR); 374 goto freeit; 375 } else { 376 /* ICMPv6 informational - send the error */ 377 } 378 } 379 #if 0 /* controversial */ 380 else if (off >= 0 && nxt == IPPROTO_ESP) { 381 /* 382 * It could be ICMPv6 error inside ESP. Take a safer side, 383 * don't respond. 384 */ 385 ICMP6_STATINC(ICMP6_STAT_CANTERROR); 386 goto freeit; 387 } 388 #endif 389 else { 390 /* non-ICMPv6 - send the error */ 391 } 392 393 oip6 = mtod(m, struct ip6_hdr *); /* adjust pointer */ 394 395 /* Finally, do rate limitation check. */ 396 if (icmp6_ratelimit(&oip6->ip6_src, type, code)) { 397 ICMP6_STATINC(ICMP6_STAT_TOOFREQ); 398 goto freeit; 399 } 400 401 /* 402 * OK, ICMP6 can be generated. 403 */ 404 405 if (m->m_pkthdr.len >= ICMPV6_PLD_MAXLEN) 406 m_adj(m, ICMPV6_PLD_MAXLEN - m->m_pkthdr.len); 407 408 preplen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 409 M_PREPEND(m, preplen, M_DONTWAIT); 410 if (m && M_UNWRITABLE(m, preplen)) 411 m = m_pullup(m, preplen); 412 if (m == NULL) { 413 nd6log((LOG_DEBUG, "ENOBUFS in icmp6_error %d\n", __LINE__)); 414 return; 415 } 416 417 nip6 = mtod(m, struct ip6_hdr *); 418 nip6->ip6_src = oip6->ip6_src; 419 nip6->ip6_dst = oip6->ip6_dst; 420 421 in6_clearscope(&oip6->ip6_src); 422 in6_clearscope(&oip6->ip6_dst); 423 424 icmp6 = (struct icmp6_hdr *)(nip6 + 1); 425 icmp6->icmp6_type = type; 426 icmp6->icmp6_code = code; 427 icmp6->icmp6_pptr = htonl((u_int32_t)param); 428 429 /* 430 * icmp6_reflect() is designed to be in the input path. 431 * icmp6_error() can be called from both input and output path, 432 * and if we are in output path rcvif could contain bogus value. 433 * clear m->m_pkthdr.rcvif for safety, we should have enough scope 434 * information in ip header (nip6). 435 */ 436 m->m_pkthdr.rcvif = NULL; 437 438 ICMP6_STATINC(ICMP6_STAT_OUTHIST + type); 439 icmp6_reflect(m, sizeof(struct ip6_hdr)); /* header order: IPv6 - ICMPv6 */ 440 441 return; 442 443 freeit: 444 /* 445 * If we can't tell whether or not we can generate ICMP6, free it. 446 */ 447 m_freem(m); 448 } 449 450 /* 451 * Process a received ICMP6 message. 452 */ 453 int 454 icmp6_input(struct mbuf **mp, int *offp, int proto) 455 { 456 struct mbuf *m = *mp, *n; 457 struct ip6_hdr *ip6, *nip6; 458 struct icmp6_hdr *icmp6, *nicmp6; 459 int off = *offp; 460 int icmp6len = m->m_pkthdr.len - *offp; 461 int code, sum, noff, i; 462 463 #define ICMP6_MAXLEN (sizeof(*nip6) + sizeof(*nicmp6) + 4) 464 KASSERT(ICMP6_MAXLEN < MCLBYTES); 465 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_msg); 466 467 /* 468 * Locate icmp6 structure in mbuf, and check 469 * that not corrupted and of at least minimum length 470 */ 471 472 if (icmp6len < sizeof(struct icmp6_hdr)) { 473 ICMP6_STATINC(ICMP6_STAT_TOOSHORT); 474 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_error); 475 goto freeit; 476 } 477 478 i = off + sizeof(*icmp6); 479 if ((m->m_len < i || M_READONLY(m)) && (m = m_pullup(m, i)) == 0) { 480 ICMP6_STATINC(ICMP6_STAT_TOOSHORT); 481 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_error); 482 goto freeit; 483 } 484 ip6 = mtod(m, struct ip6_hdr *); 485 /* 486 * calculate the checksum 487 */ 488 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 489 if (icmp6 == NULL) { 490 ICMP6_STATINC(ICMP6_STAT_TOOSHORT); 491 /* m is invalid */ 492 /*icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_error);*/ 493 return IPPROTO_DONE; 494 } 495 KASSERT(IP6_HDR_ALIGNED_P(icmp6)); 496 code = icmp6->icmp6_code; 497 498 if ((sum = in6_cksum(m, IPPROTO_ICMPV6, off, icmp6len)) != 0) { 499 nd6log((LOG_ERR, 500 "ICMP6 checksum error(%d|%x) %s\n", 501 icmp6->icmp6_type, sum, ip6_sprintf(&ip6->ip6_src))); 502 ICMP6_STATINC(ICMP6_STAT_CHECKSUM); 503 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_error); 504 goto freeit; 505 } 506 507 #if defined(NFAITH) && 0 < NFAITH 508 if (faithprefix(&ip6->ip6_dst)) { 509 /* 510 * Deliver very specific ICMP6 type only. 511 * This is important to deliver TOOBIG. Otherwise PMTUD 512 * will not work. 513 */ 514 switch (icmp6->icmp6_type) { 515 case ICMP6_DST_UNREACH: 516 case ICMP6_PACKET_TOO_BIG: 517 case ICMP6_TIME_EXCEEDED: 518 break; 519 default: 520 goto freeit; 521 } 522 } 523 #endif 524 525 ICMP6_STATINC(ICMP6_STAT_INHIST + icmp6->icmp6_type); 526 527 switch (icmp6->icmp6_type) { 528 case ICMP6_DST_UNREACH: 529 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_dstunreach); 530 switch (code) { 531 case ICMP6_DST_UNREACH_NOROUTE: 532 code = PRC_UNREACH_NET; 533 break; 534 case ICMP6_DST_UNREACH_ADMIN: 535 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_adminprohib); 536 code = PRC_UNREACH_PROTOCOL; /* is this a good code? */ 537 break; 538 case ICMP6_DST_UNREACH_ADDR: 539 code = PRC_HOSTDEAD; 540 break; 541 #ifdef COMPAT_RFC1885 542 case ICMP6_DST_UNREACH_NOTNEIGHBOR: 543 code = PRC_UNREACH_SRCFAIL; 544 break; 545 #else 546 case ICMP6_DST_UNREACH_BEYONDSCOPE: 547 /* I mean "source address was incorrect." */ 548 code = PRC_UNREACH_NET; 549 break; 550 #endif 551 case ICMP6_DST_UNREACH_NOPORT: 552 code = PRC_UNREACH_PORT; 553 break; 554 default: 555 goto badcode; 556 } 557 goto deliver; 558 559 case ICMP6_PACKET_TOO_BIG: 560 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_pkttoobig); 561 562 /* 563 * MTU is checked in icmp6_mtudisc. 564 */ 565 code = PRC_MSGSIZE; 566 567 /* 568 * Updating the path MTU will be done after examining 569 * intermediate extension headers. 570 */ 571 goto deliver; 572 573 case ICMP6_TIME_EXCEEDED: 574 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_timeexceed); 575 switch (code) { 576 case ICMP6_TIME_EXCEED_TRANSIT: 577 code = PRC_TIMXCEED_INTRANS; 578 break; 579 case ICMP6_TIME_EXCEED_REASSEMBLY: 580 code = PRC_TIMXCEED_REASS; 581 break; 582 default: 583 goto badcode; 584 } 585 goto deliver; 586 587 case ICMP6_PARAM_PROB: 588 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_paramprob); 589 switch (code) { 590 case ICMP6_PARAMPROB_NEXTHEADER: 591 code = PRC_UNREACH_PROTOCOL; 592 break; 593 case ICMP6_PARAMPROB_HEADER: 594 case ICMP6_PARAMPROB_OPTION: 595 code = PRC_PARAMPROB; 596 break; 597 default: 598 goto badcode; 599 } 600 goto deliver; 601 602 case ICMP6_ECHO_REQUEST: 603 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echo); 604 if (code != 0) 605 goto badcode; 606 /* 607 * Copy mbuf to send to two data paths: userland socket(s), 608 * and to the querier (echo reply). 609 * m: a copy for socket, n: a copy for querier 610 * 611 * If the first mbuf is shared, or the first mbuf is too short, 612 * copy the first part of the data into a fresh mbuf. 613 * Otherwise, we will wrongly overwrite both copies. 614 */ 615 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 616 /* Give up local */ 617 n = m; 618 m = NULL; 619 } else if (M_READONLY(n) || 620 n->m_len < off + sizeof(struct icmp6_hdr)) { 621 struct mbuf *n0 = n; 622 623 /* 624 * Prepare an internal mbuf. m_pullup() doesn't 625 * always copy the length we specified. 626 */ 627 if ((n = m_dup(n0, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 628 /* Give up local */ 629 n = m; 630 m = NULL; 631 } 632 m_freem(n0); 633 } 634 IP6_EXTHDR_GET(nicmp6, struct icmp6_hdr *, n, off, 635 sizeof(*nicmp6)); 636 nicmp6->icmp6_type = ICMP6_ECHO_REPLY; 637 nicmp6->icmp6_code = 0; 638 if (n) { 639 uint64_t *icmp6s = ICMP6_STAT_GETREF(); 640 icmp6s[ICMP6_STAT_REFLECT]++; 641 icmp6s[ICMP6_STAT_OUTHIST + ICMP6_ECHO_REPLY]++; 642 ICMP6_STAT_PUTREF(); 643 icmp6_reflect(n, off); 644 } 645 if (!m) 646 goto freeit; 647 break; 648 649 case ICMP6_ECHO_REPLY: 650 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echoreply); 651 if (code != 0) 652 goto badcode; 653 break; 654 655 case MLD_LISTENER_QUERY: 656 case MLD_LISTENER_REPORT: 657 if (icmp6len < sizeof(struct mld_hdr)) 658 goto badlen; 659 if (icmp6->icmp6_type == MLD_LISTENER_QUERY) /* XXX: ugly... */ 660 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldquery); 661 else 662 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldreport); 663 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 664 /* give up local */ 665 mld_input(m, off); 666 m = NULL; 667 goto freeit; 668 } 669 mld_input(n, off); 670 /* m stays. */ 671 break; 672 673 case MLD_LISTENER_DONE: 674 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mlddone); 675 if (icmp6len < sizeof(struct mld_hdr)) /* necessary? */ 676 goto badlen; 677 break; /* nothing to be done in kernel */ 678 679 case MLD_MTRACE_RESP: 680 case MLD_MTRACE: 681 /* XXX: these two are experimental. not officially defined. */ 682 /* XXX: per-interface statistics? */ 683 break; /* just pass it to applications */ 684 685 case ICMP6_WRUREQUEST: /* ICMP6_FQDN_QUERY */ 686 { 687 enum { WRU, FQDN } mode; 688 689 if (!icmp6_nodeinfo) 690 break; 691 692 if (icmp6len == sizeof(struct icmp6_hdr) + 4) 693 mode = WRU; 694 else if (icmp6len >= sizeof(struct icmp6_nodeinfo)) 695 mode = FQDN; 696 else 697 goto badlen; 698 699 if (mode == FQDN) { 700 n = m_copym(m, 0, M_COPYALL, M_DONTWAIT); 701 if (n) 702 n = ni6_input(n, off); 703 /* XXX meaningless if n == NULL */ 704 noff = sizeof(struct ip6_hdr); 705 } else { 706 u_char *p; 707 int maxhlen; 708 709 if ((icmp6_nodeinfo & 5) != 5) 710 break; 711 712 if (code != 0) 713 goto badcode; 714 MGETHDR(n, M_DONTWAIT, m->m_type); 715 if (n && ICMP6_MAXLEN > MHLEN) { 716 MCLGET(n, M_DONTWAIT); 717 if ((n->m_flags & M_EXT) == 0) { 718 m_free(n); 719 n = NULL; 720 } 721 } 722 if (n == NULL) { 723 /* Give up remote */ 724 break; 725 } 726 n->m_pkthdr.rcvif = NULL; 727 n->m_len = 0; 728 maxhlen = M_TRAILINGSPACE(n) - ICMP6_MAXLEN; 729 if (maxhlen > hostnamelen) 730 maxhlen = hostnamelen; 731 /* 732 * Copy IPv6 and ICMPv6 only. 733 */ 734 nip6 = mtod(n, struct ip6_hdr *); 735 bcopy(ip6, nip6, sizeof(struct ip6_hdr)); 736 nicmp6 = (struct icmp6_hdr *)(nip6 + 1); 737 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr)); 738 p = (u_char *)(nicmp6 + 1); 739 memset(p, 0, 4); 740 bcopy(hostname, p + 4, maxhlen); /* meaningless TTL */ 741 noff = sizeof(struct ip6_hdr); 742 M_COPY_PKTHDR(n, m); /* just for rcvif */ 743 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) + 744 sizeof(struct icmp6_hdr) + 4 + maxhlen; 745 nicmp6->icmp6_type = ICMP6_WRUREPLY; 746 nicmp6->icmp6_code = 0; 747 } 748 #undef hostnamelen 749 if (n) { 750 uint64_t *icmp6s = ICMP6_STAT_GETREF(); 751 icmp6s[ICMP6_STAT_REFLECT]++; 752 icmp6s[ICMP6_STAT_OUTHIST + ICMP6_WRUREPLY]++; 753 ICMP6_STAT_PUTREF(); 754 icmp6_reflect(n, noff); 755 } 756 break; 757 } 758 759 case ICMP6_WRUREPLY: 760 if (code != 0) 761 goto badcode; 762 break; 763 764 case ND_ROUTER_SOLICIT: 765 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routersolicit); 766 if (code != 0) 767 goto badcode; 768 if (icmp6len < sizeof(struct nd_router_solicit)) 769 goto badlen; 770 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 771 /* give up local */ 772 nd6_rs_input(m, off, icmp6len); 773 m = NULL; 774 goto freeit; 775 } 776 nd6_rs_input(n, off, icmp6len); 777 /* m stays. */ 778 break; 779 780 case ND_ROUTER_ADVERT: 781 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routeradvert); 782 if (code != 0) 783 goto badcode; 784 if (icmp6len < sizeof(struct nd_router_advert)) 785 goto badlen; 786 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 787 /* give up local */ 788 nd6_ra_input(m, off, icmp6len); 789 m = NULL; 790 goto freeit; 791 } 792 nd6_ra_input(n, off, icmp6len); 793 /* m stays. */ 794 break; 795 796 case ND_NEIGHBOR_SOLICIT: 797 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighborsolicit); 798 if (code != 0) 799 goto badcode; 800 if (icmp6len < sizeof(struct nd_neighbor_solicit)) 801 goto badlen; 802 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 803 /* give up local */ 804 nd6_ns_input(m, off, icmp6len); 805 m = NULL; 806 goto freeit; 807 } 808 nd6_ns_input(n, off, icmp6len); 809 /* m stays. */ 810 break; 811 812 case ND_NEIGHBOR_ADVERT: 813 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighboradvert); 814 if (code != 0) 815 goto badcode; 816 if (icmp6len < sizeof(struct nd_neighbor_advert)) 817 goto badlen; 818 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 819 /* give up local */ 820 nd6_na_input(m, off, icmp6len); 821 m = NULL; 822 goto freeit; 823 } 824 nd6_na_input(n, off, icmp6len); 825 /* m stays. */ 826 break; 827 828 case ND_REDIRECT: 829 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_redirect); 830 if (code != 0) 831 goto badcode; 832 if (icmp6len < sizeof(struct nd_redirect)) 833 goto badlen; 834 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 835 /* give up local */ 836 icmp6_redirect_input(m, off); 837 m = NULL; 838 goto freeit; 839 } 840 icmp6_redirect_input(n, off); 841 /* m stays. */ 842 break; 843 844 case ICMP6_ROUTER_RENUMBERING: 845 if (code != ICMP6_ROUTER_RENUMBERING_COMMAND && 846 code != ICMP6_ROUTER_RENUMBERING_RESULT) 847 goto badcode; 848 if (icmp6len < sizeof(struct icmp6_router_renum)) 849 goto badlen; 850 break; 851 852 default: 853 nd6log((LOG_DEBUG, 854 "icmp6_input: unknown type %d(src=%s, dst=%s, ifid=%d)\n", 855 icmp6->icmp6_type, ip6_sprintf(&ip6->ip6_src), 856 ip6_sprintf(&ip6->ip6_dst), 857 m->m_pkthdr.rcvif ? m->m_pkthdr.rcvif->if_index : 0)); 858 if (icmp6->icmp6_type < ICMP6_ECHO_REQUEST) { 859 /* ICMPv6 error: MUST deliver it by spec... */ 860 code = PRC_NCMDS; 861 /* deliver */ 862 } else { 863 /* ICMPv6 informational: MUST not deliver */ 864 break; 865 } 866 deliver: 867 if (icmp6_notify_error(m, off, icmp6len, code)) { 868 /* In this case, m should've been freed. */ 869 return (IPPROTO_DONE); 870 } 871 break; 872 873 badcode: 874 ICMP6_STATINC(ICMP6_STAT_BADCODE); 875 break; 876 877 badlen: 878 ICMP6_STATINC(ICMP6_STAT_BADLEN); 879 break; 880 } 881 882 /* deliver the packet to appropriate sockets */ 883 icmp6_rip6_input(&m, *offp); 884 885 return IPPROTO_DONE; 886 887 freeit: 888 m_freem(m); 889 return IPPROTO_DONE; 890 } 891 892 static int 893 icmp6_notify_error(struct mbuf *m, int off, int icmp6len, int code) 894 { 895 struct icmp6_hdr *icmp6; 896 struct ip6_hdr *eip6; 897 u_int32_t notifymtu; 898 struct sockaddr_in6 icmp6src, icmp6dst; 899 900 if (icmp6len < sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr)) { 901 ICMP6_STATINC(ICMP6_STAT_TOOSHORT); 902 goto freeit; 903 } 904 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, 905 sizeof(*icmp6) + sizeof(struct ip6_hdr)); 906 if (icmp6 == NULL) { 907 ICMP6_STATINC(ICMP6_STAT_TOOSHORT); 908 return (-1); 909 } 910 eip6 = (struct ip6_hdr *)(icmp6 + 1); 911 912 /* Detect the upper level protocol */ 913 { 914 void (*ctlfunc)(int, struct sockaddr *, void *); 915 u_int8_t nxt = eip6->ip6_nxt; 916 int eoff = off + sizeof(struct icmp6_hdr) + 917 sizeof(struct ip6_hdr); 918 struct ip6ctlparam ip6cp; 919 struct in6_addr *finaldst = NULL; 920 int icmp6type = icmp6->icmp6_type; 921 struct ip6_frag *fh; 922 struct ip6_rthdr *rth; 923 struct ip6_rthdr0 *rth0; 924 int rthlen; 925 926 while (1) { /* XXX: should avoid infinite loop explicitly? */ 927 struct ip6_ext *eh; 928 929 switch (nxt) { 930 case IPPROTO_HOPOPTS: 931 case IPPROTO_DSTOPTS: 932 case IPPROTO_AH: 933 IP6_EXTHDR_GET(eh, struct ip6_ext *, m, 934 eoff, sizeof(*eh)); 935 if (eh == NULL) { 936 ICMP6_STATINC(ICMP6_STAT_TOOSHORT); 937 return (-1); 938 } 939 940 if (nxt == IPPROTO_AH) 941 eoff += (eh->ip6e_len + 2) << 2; 942 else 943 eoff += (eh->ip6e_len + 1) << 3; 944 nxt = eh->ip6e_nxt; 945 break; 946 case IPPROTO_ROUTING: 947 /* 948 * When the erroneous packet contains a 949 * routing header, we should examine the 950 * header to determine the final destination. 951 * Otherwise, we can't properly update 952 * information that depends on the final 953 * destination (e.g. path MTU). 954 */ 955 IP6_EXTHDR_GET(rth, struct ip6_rthdr *, m, 956 eoff, sizeof(*rth)); 957 if (rth == NULL) { 958 ICMP6_STATINC(ICMP6_STAT_TOOSHORT); 959 return (-1); 960 } 961 rthlen = (rth->ip6r_len + 1) << 3; 962 /* 963 * XXX: currently there is no 964 * officially defined type other 965 * than type-0. 966 * Note that if the segment left field 967 * is 0, all intermediate hops must 968 * have been passed. 969 */ 970 if (rth->ip6r_segleft && 971 rth->ip6r_type == IPV6_RTHDR_TYPE_0) { 972 int hops; 973 974 IP6_EXTHDR_GET(rth0, 975 struct ip6_rthdr0 *, m, 976 eoff, rthlen); 977 if (rth0 == NULL) { 978 ICMP6_STATINC(ICMP6_STAT_TOOSHORT); 979 return (-1); 980 } 981 /* just ignore a bogus header */ 982 if ((rth0->ip6r0_len % 2) == 0 && 983 (hops = rth0->ip6r0_len/2)) 984 finaldst = (struct in6_addr *)(rth0 + 1) + (hops - 1); 985 } 986 eoff += rthlen; 987 nxt = rth->ip6r_nxt; 988 break; 989 case IPPROTO_FRAGMENT: 990 IP6_EXTHDR_GET(fh, struct ip6_frag *, m, 991 eoff, sizeof(*fh)); 992 if (fh == NULL) { 993 ICMP6_STATINC(ICMP6_STAT_TOOSHORT); 994 return (-1); 995 } 996 /* 997 * Data after a fragment header is meaningless 998 * unless it is the first fragment, but 999 * we'll go to the notify label for path MTU 1000 * discovery. 1001 */ 1002 if (fh->ip6f_offlg & IP6F_OFF_MASK) 1003 goto notify; 1004 1005 eoff += sizeof(struct ip6_frag); 1006 nxt = fh->ip6f_nxt; 1007 break; 1008 default: 1009 /* 1010 * This case includes ESP and the No Next 1011 * Header. In such cases going to the notify 1012 * label does not have any meaning 1013 * (i.e. ctlfunc will be NULL), but we go 1014 * anyway since we might have to update 1015 * path MTU information. 1016 */ 1017 goto notify; 1018 } 1019 } 1020 notify: 1021 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, 1022 sizeof(*icmp6) + sizeof(struct ip6_hdr)); 1023 if (icmp6 == NULL) { 1024 ICMP6_STATINC(ICMP6_STAT_TOOSHORT); 1025 return (-1); 1026 } 1027 1028 /* 1029 * retrieve parameters from the inner IPv6 header, and convert 1030 * them into sockaddr structures. 1031 * XXX: there is no guarantee that the source or destination 1032 * addresses of the inner packet are in the same scope zone as 1033 * the addresses of the icmp packet. But there is no other 1034 * way to determine the zone. 1035 */ 1036 eip6 = (struct ip6_hdr *)(icmp6 + 1); 1037 1038 sockaddr_in6_init(&icmp6dst, 1039 (finaldst == NULL) ? &eip6->ip6_dst : finaldst, 0, 0, 0); 1040 if (in6_setscope(&icmp6dst.sin6_addr, m->m_pkthdr.rcvif, NULL)) 1041 goto freeit; 1042 sockaddr_in6_init(&icmp6src, &eip6->ip6_src, 0, 0, 0); 1043 if (in6_setscope(&icmp6src.sin6_addr, m->m_pkthdr.rcvif, NULL)) 1044 goto freeit; 1045 icmp6src.sin6_flowinfo = 1046 (eip6->ip6_flow & IPV6_FLOWLABEL_MASK); 1047 1048 if (finaldst == NULL) 1049 finaldst = &eip6->ip6_dst; 1050 ip6cp.ip6c_m = m; 1051 ip6cp.ip6c_icmp6 = icmp6; 1052 ip6cp.ip6c_ip6 = (struct ip6_hdr *)(icmp6 + 1); 1053 ip6cp.ip6c_off = eoff; 1054 ip6cp.ip6c_finaldst = finaldst; 1055 ip6cp.ip6c_src = &icmp6src; 1056 ip6cp.ip6c_nxt = nxt; 1057 1058 if (icmp6type == ICMP6_PACKET_TOO_BIG) { 1059 notifymtu = ntohl(icmp6->icmp6_mtu); 1060 ip6cp.ip6c_cmdarg = (void *)¬ifymtu; 1061 } 1062 1063 ctlfunc = (void (*)(int, struct sockaddr *, void *)) 1064 (inet6sw[ip6_protox[nxt]].pr_ctlinput); 1065 if (ctlfunc) { 1066 (void) (*ctlfunc)(code, (struct sockaddr *)&icmp6dst, 1067 &ip6cp); 1068 } 1069 } 1070 return (0); 1071 1072 freeit: 1073 m_freem(m); 1074 return (-1); 1075 } 1076 1077 void 1078 icmp6_mtudisc_update(struct ip6ctlparam *ip6cp, int validated) 1079 { 1080 unsigned long rtcount; 1081 struct icmp6_mtudisc_callback *mc; 1082 struct in6_addr *dst = ip6cp->ip6c_finaldst; 1083 struct icmp6_hdr *icmp6 = ip6cp->ip6c_icmp6; 1084 struct mbuf *m = ip6cp->ip6c_m; /* will be necessary for scope issue */ 1085 u_int mtu = ntohl(icmp6->icmp6_mtu); 1086 struct rtentry *rt = NULL; 1087 struct sockaddr_in6 sin6; 1088 1089 /* 1090 * The MTU should not be less than the minimal IPv6 MTU except for the 1091 * hack in ip6_output/ip6_setpmtu where we always include a frag header. 1092 * In that one case, the MTU might be less than 1280. 1093 */ 1094 if (__predict_false(mtu < IPV6_MMTU - sizeof(struct ip6_frag))) { 1095 /* is the mtu even sane? */ 1096 if (mtu < sizeof(struct ip6_hdr) + sizeof(struct ip6_frag) + 8) 1097 return; 1098 if (!validated) 1099 return; 1100 mtu = IPV6_MMTU - sizeof(struct ip6_frag); 1101 } 1102 1103 /* 1104 * allow non-validated cases if memory is plenty, to make traffic 1105 * from non-connected pcb happy. 1106 */ 1107 rtcount = rt_timer_count(icmp6_mtudisc_timeout_q); 1108 if (validated) { 1109 if (0 <= icmp6_mtudisc_hiwat && rtcount > icmp6_mtudisc_hiwat) 1110 return; 1111 else if (0 <= icmp6_mtudisc_lowat && 1112 rtcount > icmp6_mtudisc_lowat) { 1113 /* 1114 * XXX nuke a victim, install the new one. 1115 */ 1116 } 1117 } else { 1118 if (0 <= icmp6_mtudisc_lowat && rtcount > icmp6_mtudisc_lowat) 1119 return; 1120 } 1121 1122 memset(&sin6, 0, sizeof(sin6)); 1123 sin6.sin6_family = PF_INET6; 1124 sin6.sin6_len = sizeof(struct sockaddr_in6); 1125 sin6.sin6_addr = *dst; 1126 if (in6_setscope(&sin6.sin6_addr, m->m_pkthdr.rcvif, NULL)) 1127 return; 1128 1129 rt = icmp6_mtudisc_clone((struct sockaddr *)&sin6); 1130 1131 if (rt && (rt->rt_flags & RTF_HOST) && 1132 !(rt->rt_rmx.rmx_locks & RTV_MTU) && 1133 (rt->rt_rmx.rmx_mtu > mtu || rt->rt_rmx.rmx_mtu == 0)) { 1134 if (mtu < IN6_LINKMTU(rt->rt_ifp)) { 1135 ICMP6_STATINC(ICMP6_STAT_PMTUCHG); 1136 rt->rt_rmx.rmx_mtu = mtu; 1137 } 1138 } 1139 if (rt) { /* XXX: need braces to avoid conflict with else in RTFREE. */ 1140 RTFREE(rt); 1141 } 1142 1143 /* 1144 * Notify protocols that the MTU for this destination 1145 * has changed. 1146 */ 1147 for (mc = LIST_FIRST(&icmp6_mtudisc_callbacks); mc != NULL; 1148 mc = LIST_NEXT(mc, mc_list)) 1149 (*mc->mc_func)(&sin6.sin6_addr); 1150 } 1151 1152 /* 1153 * Process a Node Information Query packet, based on 1154 * draft-ietf-ipngwg-icmp-name-lookups-07. 1155 * 1156 * Spec incompatibilities: 1157 * - IPv6 Subject address handling 1158 * - IPv4 Subject address handling support missing 1159 * - Proxy reply (answer even if it's not for me) 1160 * - joins NI group address at in6_ifattach() time only, does not cope 1161 * with hostname changes by sethostname(3) 1162 */ 1163 #ifndef offsetof /* XXX */ 1164 #define offsetof(type, member) ((size_t)(&((type *)0)->member)) 1165 #endif 1166 static struct mbuf * 1167 ni6_input(struct mbuf *m, int off) 1168 { 1169 struct icmp6_nodeinfo *ni6, *nni6; 1170 struct mbuf *n = NULL; 1171 u_int16_t qtype; 1172 int subjlen; 1173 int replylen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo); 1174 struct ni_reply_fqdn *fqdn; 1175 int addrs; /* for NI_QTYPE_NODEADDR */ 1176 struct ifnet *ifp = NULL; /* for NI_QTYPE_NODEADDR */ 1177 struct sockaddr_in6 sin6; /* ip6_dst */ 1178 struct in6_addr in6_subj; /* subject address */ 1179 struct ip6_hdr *ip6; 1180 int oldfqdn = 0; /* if 1, return pascal string (03 draft) */ 1181 char *subj = NULL; 1182 1183 ip6 = mtod(m, struct ip6_hdr *); 1184 IP6_EXTHDR_GET(ni6, struct icmp6_nodeinfo *, m, off, sizeof(*ni6)); 1185 if (ni6 == NULL) { 1186 /* m is already reclaimed */ 1187 return NULL; 1188 } 1189 1190 /* 1191 * Validate IPv6 destination address. 1192 * 1193 * The Responder must discard the Query without further processing 1194 * unless it is one of the Responder's unicast or anycast addresses, or 1195 * a link-local scope multicast address which the Responder has joined. 1196 * [icmp-name-lookups-07, Section 4.] 1197 */ 1198 sockaddr_in6_init(&sin6, &ip6->ip6_dst, 0, 0, 0); 1199 /* XXX scopeid */ 1200 if (ifa_ifwithaddr((struct sockaddr *)&sin6)) 1201 ; /* unicast/anycast, fine */ 1202 else if (IN6_IS_ADDR_MC_LINKLOCAL(&sin6.sin6_addr)) 1203 ; /* link-local multicast, fine */ 1204 else 1205 goto bad; 1206 1207 /* validate query Subject field. */ 1208 qtype = ntohs(ni6->ni_qtype); 1209 subjlen = m->m_pkthdr.len - off - sizeof(struct icmp6_nodeinfo); 1210 switch (qtype) { 1211 case NI_QTYPE_NOOP: 1212 case NI_QTYPE_SUPTYPES: 1213 /* 07 draft */ 1214 if (ni6->ni_code == ICMP6_NI_SUBJ_FQDN && subjlen == 0) 1215 break; 1216 /* FALLTHROUGH */ 1217 case NI_QTYPE_FQDN: 1218 case NI_QTYPE_NODEADDR: 1219 case NI_QTYPE_IPV4ADDR: 1220 switch (ni6->ni_code) { 1221 case ICMP6_NI_SUBJ_IPV6: 1222 #if ICMP6_NI_SUBJ_IPV6 != 0 1223 case 0: 1224 #endif 1225 /* 1226 * backward compatibility - try to accept 03 draft 1227 * format, where no Subject is present. 1228 */ 1229 if (qtype == NI_QTYPE_FQDN && ni6->ni_code == 0 && 1230 subjlen == 0) { 1231 oldfqdn++; 1232 break; 1233 } 1234 #if ICMP6_NI_SUBJ_IPV6 != 0 1235 if (ni6->ni_code != ICMP6_NI_SUBJ_IPV6) 1236 goto bad; 1237 #endif 1238 1239 if (subjlen != sizeof(sin6.sin6_addr)) 1240 goto bad; 1241 1242 /* 1243 * Validate Subject address. 1244 * 1245 * Not sure what exactly "address belongs to the node" 1246 * means in the spec, is it just unicast, or what? 1247 * 1248 * At this moment we consider Subject address as 1249 * "belong to the node" if the Subject address equals 1250 * to the IPv6 destination address; validation for 1251 * IPv6 destination address should have done enough 1252 * check for us. 1253 * 1254 * We do not do proxy at this moment. 1255 */ 1256 /* m_pulldown instead of copy? */ 1257 m_copydata(m, off + sizeof(struct icmp6_nodeinfo), 1258 subjlen, (void *)&in6_subj); 1259 if (in6_setscope(&in6_subj, m->m_pkthdr.rcvif, NULL)) 1260 goto bad; 1261 1262 subj = (char *)&in6_subj; 1263 if (IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, &in6_subj)) 1264 break; 1265 1266 /* 1267 * XXX if we are to allow other cases, we should really 1268 * be careful about scope here. 1269 * basically, we should disallow queries toward IPv6 1270 * destination X with subject Y, if scope(X) > scope(Y). 1271 * if we allow scope(X) > scope(Y), it will result in 1272 * information leakage across scope boundary. 1273 */ 1274 goto bad; 1275 1276 case ICMP6_NI_SUBJ_FQDN: 1277 /* 1278 * Validate Subject name with gethostname(3). 1279 * 1280 * The behavior may need some debate, since: 1281 * - we are not sure if the node has FQDN as 1282 * hostname (returned by gethostname(3)). 1283 * - the code does wildcard match for truncated names. 1284 * however, we are not sure if we want to perform 1285 * wildcard match, if gethostname(3) side has 1286 * truncated hostname. 1287 */ 1288 n = ni6_nametodns(hostname, hostnamelen, 0); 1289 if (!n || n->m_next || n->m_len == 0) 1290 goto bad; 1291 IP6_EXTHDR_GET(subj, char *, m, 1292 off + sizeof(struct icmp6_nodeinfo), subjlen); 1293 if (subj == NULL) 1294 goto bad; 1295 if (!ni6_dnsmatch(subj, subjlen, mtod(n, const char *), 1296 n->m_len)) { 1297 goto bad; 1298 } 1299 m_freem(n); 1300 n = NULL; 1301 break; 1302 1303 case ICMP6_NI_SUBJ_IPV4: /* XXX: to be implemented? */ 1304 default: 1305 goto bad; 1306 } 1307 break; 1308 } 1309 1310 /* refuse based on configuration. XXX ICMP6_NI_REFUSED? */ 1311 switch (qtype) { 1312 case NI_QTYPE_FQDN: 1313 if ((icmp6_nodeinfo & 1) == 0) 1314 goto bad; 1315 break; 1316 case NI_QTYPE_NODEADDR: 1317 case NI_QTYPE_IPV4ADDR: 1318 if ((icmp6_nodeinfo & 2) == 0) 1319 goto bad; 1320 break; 1321 } 1322 1323 /* guess reply length */ 1324 switch (qtype) { 1325 case NI_QTYPE_NOOP: 1326 break; /* no reply data */ 1327 case NI_QTYPE_SUPTYPES: 1328 replylen += sizeof(u_int32_t); 1329 break; 1330 case NI_QTYPE_FQDN: 1331 /* XXX will append an mbuf */ 1332 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1333 break; 1334 case NI_QTYPE_NODEADDR: 1335 addrs = ni6_addrs(ni6, m, &ifp, subj); 1336 if ((replylen += addrs * (sizeof(struct in6_addr) + 1337 sizeof(u_int32_t))) > MCLBYTES) 1338 replylen = MCLBYTES; /* XXX: will truncate pkt later */ 1339 break; 1340 case NI_QTYPE_IPV4ADDR: 1341 /* unsupported - should respond with unknown Qtype? */ 1342 goto bad; 1343 default: 1344 /* 1345 * XXX: We must return a reply with the ICMP6 code 1346 * `unknown Qtype' in this case. However we regard the case 1347 * as an FQDN query for backward compatibility. 1348 * Older versions set a random value to this field, 1349 * so it rarely varies in the defined qtypes. 1350 * But the mechanism is not reliable... 1351 * maybe we should obsolete older versions. 1352 */ 1353 qtype = NI_QTYPE_FQDN; 1354 /* XXX will append an mbuf */ 1355 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1356 oldfqdn++; 1357 break; 1358 } 1359 1360 /* allocate an mbuf to reply. */ 1361 MGETHDR(n, M_DONTWAIT, m->m_type); 1362 if (n == NULL) { 1363 m_freem(m); 1364 return (NULL); 1365 } 1366 M_MOVE_PKTHDR(n, m); /* just for rcvif */ 1367 if (replylen > MHLEN) { 1368 if (replylen > MCLBYTES) { 1369 /* 1370 * XXX: should we try to allocate more? But MCLBYTES 1371 * is probably much larger than IPV6_MMTU... 1372 */ 1373 goto bad; 1374 } 1375 MCLGET(n, M_DONTWAIT); 1376 if ((n->m_flags & M_EXT) == 0) { 1377 goto bad; 1378 } 1379 } 1380 n->m_pkthdr.len = n->m_len = replylen; 1381 1382 /* copy mbuf header and IPv6 + Node Information base headers */ 1383 bcopy(mtod(m, void *), mtod(n, void *), sizeof(struct ip6_hdr)); 1384 nni6 = (struct icmp6_nodeinfo *)(mtod(n, struct ip6_hdr *) + 1); 1385 bcopy((void *)ni6, (void *)nni6, sizeof(struct icmp6_nodeinfo)); 1386 1387 /* qtype dependent procedure */ 1388 switch (qtype) { 1389 case NI_QTYPE_NOOP: 1390 nni6->ni_code = ICMP6_NI_SUCCESS; 1391 nni6->ni_flags = 0; 1392 break; 1393 case NI_QTYPE_SUPTYPES: 1394 { 1395 u_int32_t v; 1396 nni6->ni_code = ICMP6_NI_SUCCESS; 1397 nni6->ni_flags = htons(0x0000); /* raw bitmap */ 1398 /* supports NOOP, SUPTYPES, FQDN, and NODEADDR */ 1399 v = (u_int32_t)htonl(0x0000000f); 1400 bcopy(&v, nni6 + 1, sizeof(u_int32_t)); 1401 break; 1402 } 1403 case NI_QTYPE_FQDN: 1404 nni6->ni_code = ICMP6_NI_SUCCESS; 1405 fqdn = (struct ni_reply_fqdn *)(mtod(n, char *) + 1406 sizeof(struct ip6_hdr) + 1407 sizeof(struct icmp6_nodeinfo)); 1408 nni6->ni_flags = 0; /* XXX: meaningless TTL */ 1409 fqdn->ni_fqdn_ttl = 0; /* ditto. */ 1410 /* 1411 * XXX do we really have FQDN in variable "hostname"? 1412 */ 1413 n->m_next = ni6_nametodns(hostname, hostnamelen, oldfqdn); 1414 if (n->m_next == NULL) 1415 goto bad; 1416 /* XXX we assume that n->m_next is not a chain */ 1417 if (n->m_next->m_next != NULL) 1418 goto bad; 1419 n->m_pkthdr.len += n->m_next->m_len; 1420 break; 1421 case NI_QTYPE_NODEADDR: 1422 { 1423 int lenlim, copied; 1424 1425 nni6->ni_code = ICMP6_NI_SUCCESS; 1426 n->m_pkthdr.len = n->m_len = 1427 sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo); 1428 lenlim = M_TRAILINGSPACE(n); 1429 copied = ni6_store_addrs(ni6, nni6, ifp, lenlim); 1430 /* XXX: reset mbuf length */ 1431 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) + 1432 sizeof(struct icmp6_nodeinfo) + copied; 1433 break; 1434 } 1435 default: 1436 break; /* XXX impossible! */ 1437 } 1438 1439 nni6->ni_type = ICMP6_NI_REPLY; 1440 m_freem(m); 1441 return (n); 1442 1443 bad: 1444 m_freem(m); 1445 if (n) 1446 m_freem(n); 1447 return (NULL); 1448 } 1449 #undef hostnamelen 1450 1451 #define isupper(x) ('A' <= (x) && (x) <= 'Z') 1452 #define isalpha(x) (('A' <= (x) && (x) <= 'Z') || ('a' <= (x) && (x) <= 'z')) 1453 #define isalnum(x) (isalpha(x) || ('0' <= (x) && (x) <= '9')) 1454 #define tolower(x) (isupper(x) ? (x) + 'a' - 'A' : (x)) 1455 1456 /* 1457 * make a mbuf with DNS-encoded string. no compression support. 1458 * 1459 * XXX names with less than 2 dots (like "foo" or "foo.section") will be 1460 * treated as truncated name (two \0 at the end). this is a wild guess. 1461 * 1462 * old - return pascal string if non-zero 1463 */ 1464 static struct mbuf * 1465 ni6_nametodns(const char *name, int namelen, int old) 1466 { 1467 struct mbuf *m; 1468 char *cp, *ep; 1469 const char *p, *q; 1470 int i, len, nterm; 1471 1472 if (old) 1473 len = namelen + 1; 1474 else 1475 len = MCLBYTES; 1476 1477 /* because MAXHOSTNAMELEN is usually 256, we use cluster mbuf */ 1478 MGET(m, M_DONTWAIT, MT_DATA); 1479 if (m && len > MLEN) { 1480 MCLGET(m, M_DONTWAIT); 1481 if ((m->m_flags & M_EXT) == 0) 1482 goto fail; 1483 } 1484 if (!m) 1485 goto fail; 1486 m->m_next = NULL; 1487 1488 if (old) { 1489 m->m_len = len; 1490 *mtod(m, char *) = namelen; 1491 bcopy(name, mtod(m, char *) + 1, namelen); 1492 return m; 1493 } else { 1494 m->m_len = 0; 1495 cp = mtod(m, char *); 1496 ep = mtod(m, char *) + M_TRAILINGSPACE(m); 1497 1498 /* if not certain about my name, return empty buffer */ 1499 if (namelen == 0) 1500 return m; 1501 1502 /* 1503 * guess if it looks like shortened hostname, or FQDN. 1504 * shortened hostname needs two trailing "\0". 1505 */ 1506 i = 0; 1507 for (p = name; p < name + namelen; p++) { 1508 if (*p && *p == '.') 1509 i++; 1510 } 1511 if (i < 2) 1512 nterm = 2; 1513 else 1514 nterm = 1; 1515 1516 p = name; 1517 while (cp < ep && p < name + namelen) { 1518 i = 0; 1519 for (q = p; q < name + namelen && *q && *q != '.'; q++) 1520 i++; 1521 /* result does not fit into mbuf */ 1522 if (cp + i + 1 >= ep) 1523 goto fail; 1524 /* 1525 * DNS label length restriction, RFC1035 page 8. 1526 * "i == 0" case is included here to avoid returning 1527 * 0-length label on "foo..bar". 1528 */ 1529 if (i <= 0 || i >= 64) 1530 goto fail; 1531 *cp++ = i; 1532 if (!isalpha(p[0]) || !isalnum(p[i - 1])) 1533 goto fail; 1534 while (i > 0) { 1535 if (!isalnum(*p) && *p != '-') 1536 goto fail; 1537 if (isupper(*p)) { 1538 *cp++ = tolower(*p); 1539 p++; 1540 } else 1541 *cp++ = *p++; 1542 i--; 1543 } 1544 p = q; 1545 if (p < name + namelen && *p == '.') 1546 p++; 1547 } 1548 /* termination */ 1549 if (cp + nterm >= ep) 1550 goto fail; 1551 while (nterm-- > 0) 1552 *cp++ = '\0'; 1553 m->m_len = cp - mtod(m, char *); 1554 return m; 1555 } 1556 1557 panic("should not reach here"); 1558 /* NOTREACHED */ 1559 1560 fail: 1561 if (m) 1562 m_freem(m); 1563 return NULL; 1564 } 1565 1566 /* 1567 * check if two DNS-encoded string matches. takes care of truncated 1568 * form (with \0\0 at the end). no compression support. 1569 * XXX upper/lowercase match (see RFC2065) 1570 */ 1571 static int 1572 ni6_dnsmatch(const char *a, int alen, const char *b, int blen) 1573 { 1574 const char *a0, *b0; 1575 int l; 1576 1577 /* simplest case - need validation? */ 1578 if (alen == blen && memcmp(a, b, alen) == 0) 1579 return 1; 1580 1581 a0 = a; 1582 b0 = b; 1583 1584 /* termination is mandatory */ 1585 if (alen < 2 || blen < 2) 1586 return 0; 1587 if (a0[alen - 1] != '\0' || b0[blen - 1] != '\0') 1588 return 0; 1589 alen--; 1590 blen--; 1591 1592 while (a - a0 < alen && b - b0 < blen) { 1593 if (a - a0 + 1 > alen || b - b0 + 1 > blen) 1594 return 0; 1595 1596 if ((signed char)a[0] < 0 || (signed char)b[0] < 0) 1597 return 0; 1598 /* we don't support compression yet */ 1599 if (a[0] >= 64 || b[0] >= 64) 1600 return 0; 1601 1602 /* truncated case */ 1603 if (a[0] == 0 && a - a0 == alen - 1) 1604 return 1; 1605 if (b[0] == 0 && b - b0 == blen - 1) 1606 return 1; 1607 if (a[0] == 0 || b[0] == 0) 1608 return 0; 1609 1610 if (a[0] != b[0]) 1611 return 0; 1612 l = a[0]; 1613 if (a - a0 + 1 + l > alen || b - b0 + 1 + l > blen) 1614 return 0; 1615 if (memcmp(a + 1, b + 1, l) != 0) 1616 return 0; 1617 1618 a += 1 + l; 1619 b += 1 + l; 1620 } 1621 1622 if (a - a0 == alen && b - b0 == blen) 1623 return 1; 1624 else 1625 return 0; 1626 } 1627 1628 /* 1629 * calculate the number of addresses to be returned in the node info reply. 1630 */ 1631 static int 1632 ni6_addrs(struct icmp6_nodeinfo *ni6, struct mbuf *m, 1633 struct ifnet **ifpp, char *subj) 1634 { 1635 struct ifnet *ifp; 1636 struct in6_ifaddr *ifa6; 1637 struct ifaddr *ifa; 1638 struct sockaddr_in6 *subj_ip6 = NULL; /* XXX pedant */ 1639 int addrs = 0, addrsofif, iffound = 0; 1640 int niflags = ni6->ni_flags; 1641 1642 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0) { 1643 switch (ni6->ni_code) { 1644 case ICMP6_NI_SUBJ_IPV6: 1645 if (subj == NULL) /* must be impossible... */ 1646 return (0); 1647 subj_ip6 = (struct sockaddr_in6 *)subj; 1648 break; 1649 default: 1650 /* 1651 * XXX: we only support IPv6 subject address for 1652 * this Qtype. 1653 */ 1654 return (0); 1655 } 1656 } 1657 1658 IFNET_FOREACH(ifp) { 1659 addrsofif = 0; 1660 IFADDR_FOREACH(ifa, ifp) { 1661 if (ifa->ifa_addr->sa_family != AF_INET6) 1662 continue; 1663 ifa6 = (struct in6_ifaddr *)ifa; 1664 1665 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0 && 1666 IN6_ARE_ADDR_EQUAL(&subj_ip6->sin6_addr, 1667 &ifa6->ia_addr.sin6_addr)) 1668 iffound = 1; 1669 1670 /* 1671 * IPv4-mapped addresses can only be returned by a 1672 * Node Information proxy, since they represent 1673 * addresses of IPv4-only nodes, which perforce do 1674 * not implement this protocol. 1675 * [icmp-name-lookups-07, Section 5.4] 1676 * So we don't support NI_NODEADDR_FLAG_COMPAT in 1677 * this function at this moment. 1678 */ 1679 1680 /* What do we have to do about ::1? */ 1681 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1682 case IPV6_ADDR_SCOPE_LINKLOCAL: 1683 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0) 1684 continue; 1685 break; 1686 case IPV6_ADDR_SCOPE_SITELOCAL: 1687 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0) 1688 continue; 1689 break; 1690 case IPV6_ADDR_SCOPE_GLOBAL: 1691 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0) 1692 continue; 1693 break; 1694 default: 1695 continue; 1696 } 1697 1698 /* 1699 * check if anycast is okay. 1700 * XXX: just experimental. not in the spec. 1701 */ 1702 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 && 1703 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0) 1704 continue; /* we need only unicast addresses */ 1705 1706 addrsofif++; /* count the address */ 1707 } 1708 if (iffound) { 1709 *ifpp = ifp; 1710 return (addrsofif); 1711 } 1712 1713 addrs += addrsofif; 1714 } 1715 1716 return (addrs); 1717 } 1718 1719 static int 1720 ni6_store_addrs(struct icmp6_nodeinfo *ni6, 1721 struct icmp6_nodeinfo *nni6, struct ifnet *ifp0, 1722 int resid) 1723 { 1724 struct ifnet *ifp = ifp0 ? ifp0 : TAILQ_FIRST(&ifnet); 1725 struct in6_ifaddr *ifa6; 1726 struct ifaddr *ifa; 1727 struct ifnet *ifp_dep = NULL; 1728 int copied = 0, allow_deprecated = 0; 1729 u_char *cp = (u_char *)(nni6 + 1); 1730 int niflags = ni6->ni_flags; 1731 u_int32_t ltime; 1732 1733 if (ifp0 == NULL && !(niflags & NI_NODEADDR_FLAG_ALL)) 1734 return (0); /* needless to copy */ 1735 1736 again: 1737 1738 for (; ifp; ifp = TAILQ_NEXT(ifp, if_list)) 1739 { 1740 IFADDR_FOREACH(ifa, ifp) { 1741 if (ifa->ifa_addr->sa_family != AF_INET6) 1742 continue; 1743 ifa6 = (struct in6_ifaddr *)ifa; 1744 1745 if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) != 0 && 1746 allow_deprecated == 0) { 1747 /* 1748 * prefererred address should be put before 1749 * deprecated addresses. 1750 */ 1751 1752 /* record the interface for later search */ 1753 if (ifp_dep == NULL) 1754 ifp_dep = ifp; 1755 1756 continue; 1757 } 1758 else if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) == 0 && 1759 allow_deprecated != 0) 1760 continue; /* we now collect deprecated addrs */ 1761 1762 /* What do we have to do about ::1? */ 1763 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1764 case IPV6_ADDR_SCOPE_LINKLOCAL: 1765 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0) 1766 continue; 1767 break; 1768 case IPV6_ADDR_SCOPE_SITELOCAL: 1769 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0) 1770 continue; 1771 break; 1772 case IPV6_ADDR_SCOPE_GLOBAL: 1773 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0) 1774 continue; 1775 break; 1776 default: 1777 continue; 1778 } 1779 1780 /* 1781 * check if anycast is okay. 1782 * XXX: just experimental. not in the spec. 1783 */ 1784 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 && 1785 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0) 1786 continue; 1787 1788 /* now we can copy the address */ 1789 if (resid < sizeof(struct in6_addr) + 1790 sizeof(u_int32_t)) { 1791 /* 1792 * We give up much more copy. 1793 * Set the truncate flag and return. 1794 */ 1795 nni6->ni_flags |= NI_NODEADDR_FLAG_TRUNCATE; 1796 return (copied); 1797 } 1798 1799 /* 1800 * Set the TTL of the address. 1801 * The TTL value should be one of the following 1802 * according to the specification: 1803 * 1804 * 1. The remaining lifetime of a DHCP lease on the 1805 * address, or 1806 * 2. The remaining Valid Lifetime of a prefix from 1807 * which the address was derived through Stateless 1808 * Autoconfiguration. 1809 * 1810 * Note that we currently do not support stateful 1811 * address configuration by DHCPv6, so the former 1812 * case can't happen. 1813 * 1814 * TTL must be 2^31 > TTL >= 0. 1815 */ 1816 if (ifa6->ia6_lifetime.ia6t_expire == 0) 1817 ltime = ND6_INFINITE_LIFETIME; 1818 else { 1819 if (ifa6->ia6_lifetime.ia6t_expire > 1820 time_second) 1821 ltime = ifa6->ia6_lifetime.ia6t_expire - 1822 time_second; 1823 else 1824 ltime = 0; 1825 } 1826 if (ltime > 0x7fffffff) 1827 ltime = 0x7fffffff; 1828 ltime = htonl(ltime); 1829 1830 bcopy(<ime, cp, sizeof(u_int32_t)); 1831 cp += sizeof(u_int32_t); 1832 1833 /* copy the address itself */ 1834 bcopy(&ifa6->ia_addr.sin6_addr, cp, 1835 sizeof(struct in6_addr)); 1836 in6_clearscope((struct in6_addr *)cp); /* XXX */ 1837 cp += sizeof(struct in6_addr); 1838 1839 resid -= (sizeof(struct in6_addr) + sizeof(u_int32_t)); 1840 copied += (sizeof(struct in6_addr) + sizeof(u_int32_t)); 1841 } 1842 if (ifp0) /* we need search only on the specified IF */ 1843 break; 1844 } 1845 1846 if (allow_deprecated == 0 && ifp_dep != NULL) { 1847 ifp = ifp_dep; 1848 allow_deprecated = 1; 1849 1850 goto again; 1851 } 1852 1853 return (copied); 1854 } 1855 1856 /* 1857 * XXX almost dup'ed code with rip6_input. 1858 */ 1859 static int 1860 icmp6_rip6_input(struct mbuf **mp, int off) 1861 { 1862 struct mbuf *m = *mp; 1863 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1864 struct inpcb_hdr *inph; 1865 struct in6pcb *in6p; 1866 struct in6pcb *last = NULL; 1867 struct sockaddr_in6 rip6src; 1868 struct icmp6_hdr *icmp6; 1869 struct mbuf *opts = NULL; 1870 1871 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 1872 if (icmp6 == NULL) { 1873 /* m is already reclaimed */ 1874 return IPPROTO_DONE; 1875 } 1876 1877 /* 1878 * XXX: the address may have embedded scope zone ID, which should be 1879 * hidden from applications. 1880 */ 1881 sockaddr_in6_init(&rip6src, &ip6->ip6_src, 0, 0, 0); 1882 if (sa6_recoverscope(&rip6src)) { 1883 m_freem(m); 1884 return (IPPROTO_DONE); 1885 } 1886 1887 CIRCLEQ_FOREACH(inph, &raw6cbtable.inpt_queue, inph_queue) { 1888 in6p = (struct in6pcb *)inph; 1889 if (in6p->in6p_af != AF_INET6) 1890 continue; 1891 if (in6p->in6p_ip6.ip6_nxt != IPPROTO_ICMPV6) 1892 continue; 1893 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr) && 1894 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr, &ip6->ip6_dst)) 1895 continue; 1896 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr) && 1897 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr, &ip6->ip6_src)) 1898 continue; 1899 if (in6p->in6p_icmp6filt 1900 && ICMP6_FILTER_WILLBLOCK(icmp6->icmp6_type, 1901 in6p->in6p_icmp6filt)) 1902 continue; 1903 if (last) { 1904 struct mbuf *n; 1905 if ((n = m_copy(m, 0, (int)M_COPYALL)) != NULL) { 1906 if (last->in6p_flags & IN6P_CONTROLOPTS) 1907 ip6_savecontrol(last, &opts, ip6, n); 1908 /* strip intermediate headers */ 1909 m_adj(n, off); 1910 if (sbappendaddr(&last->in6p_socket->so_rcv, 1911 (struct sockaddr *)&rip6src, 1912 n, opts) == 0) { 1913 /* should notify about lost packet */ 1914 m_freem(n); 1915 if (opts) 1916 m_freem(opts); 1917 } else 1918 sorwakeup(last->in6p_socket); 1919 opts = NULL; 1920 } 1921 } 1922 last = in6p; 1923 } 1924 if (last) { 1925 if (last->in6p_flags & IN6P_CONTROLOPTS) 1926 ip6_savecontrol(last, &opts, ip6, m); 1927 /* strip intermediate headers */ 1928 m_adj(m, off); 1929 if (sbappendaddr(&last->in6p_socket->so_rcv, 1930 (struct sockaddr *)&rip6src, m, opts) == 0) { 1931 m_freem(m); 1932 if (opts) 1933 m_freem(opts); 1934 } else 1935 sorwakeup(last->in6p_socket); 1936 } else { 1937 m_freem(m); 1938 IP6_STATDEC(IP6_STAT_DELIVERED); 1939 } 1940 return IPPROTO_DONE; 1941 } 1942 1943 /* 1944 * Reflect the ip6 packet back to the source. 1945 * OFF points to the icmp6 header, counted from the top of the mbuf. 1946 * 1947 * Note: RFC 1885 required that an echo reply should be truncated if it 1948 * did not fit in with (return) path MTU, and KAME code supported the 1949 * behavior. However, as a clarification after the RFC, this limitation 1950 * was removed in a revised version of the spec, RFC 2463. We had kept the 1951 * old behavior, with a (non-default) ifdef block, while the new version of 1952 * the spec was an internet-draft status, and even after the new RFC was 1953 * published. But it would rather make sense to clean the obsoleted part 1954 * up, and to make the code simpler at this stage. 1955 */ 1956 void 1957 icmp6_reflect(struct mbuf *m, size_t off) 1958 { 1959 struct ip6_hdr *ip6; 1960 struct icmp6_hdr *icmp6; 1961 const struct in6_ifaddr *ia; 1962 const struct ip6aux *ip6a; 1963 int plen; 1964 int type, code; 1965 struct ifnet *outif = NULL; 1966 struct in6_addr origdst; 1967 const struct in6_addr *src = NULL; 1968 1969 /* too short to reflect */ 1970 if (off < sizeof(struct ip6_hdr)) { 1971 nd6log((LOG_DEBUG, 1972 "sanity fail: off=%lx, sizeof(ip6)=%lx in %s:%d\n", 1973 (u_long)off, (u_long)sizeof(struct ip6_hdr), 1974 __FILE__, __LINE__)); 1975 goto bad; 1976 } 1977 1978 /* 1979 * If there are extra headers between IPv6 and ICMPv6, strip 1980 * off that header first. 1981 */ 1982 #ifdef DIAGNOSTIC 1983 if (sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) > MHLEN) 1984 panic("assumption failed in icmp6_reflect"); 1985 #endif 1986 if (off > sizeof(struct ip6_hdr)) { 1987 size_t l; 1988 struct ip6_hdr nip6; 1989 1990 l = off - sizeof(struct ip6_hdr); 1991 m_copydata(m, 0, sizeof(nip6), (void *)&nip6); 1992 m_adj(m, l); 1993 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 1994 if (m->m_len < l) { 1995 if ((m = m_pullup(m, l)) == NULL) 1996 return; 1997 } 1998 bcopy((void *)&nip6, mtod(m, void *), sizeof(nip6)); 1999 } else /* off == sizeof(struct ip6_hdr) */ { 2000 size_t l; 2001 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 2002 if (m->m_len < l) { 2003 if ((m = m_pullup(m, l)) == NULL) 2004 return; 2005 } 2006 } 2007 plen = m->m_pkthdr.len - sizeof(struct ip6_hdr); 2008 ip6 = mtod(m, struct ip6_hdr *); 2009 ip6->ip6_nxt = IPPROTO_ICMPV6; 2010 icmp6 = (struct icmp6_hdr *)(ip6 + 1); 2011 type = icmp6->icmp6_type; /* keep type for statistics */ 2012 code = icmp6->icmp6_code; /* ditto. */ 2013 2014 origdst = ip6->ip6_dst; 2015 /* 2016 * ip6_input() drops a packet if its src is multicast. 2017 * So, the src is never multicast. 2018 */ 2019 ip6->ip6_dst = ip6->ip6_src; 2020 2021 /* 2022 * If the incoming packet was addressed directly to us (i.e. unicast), 2023 * use dst as the src for the reply. 2024 * The IN6_IFF_NOTREADY case should be VERY rare, but is possible 2025 * (for example) when we encounter an error while forwarding procedure 2026 * destined to a duplicated address of ours. 2027 * Note that ip6_getdstifaddr() may fail if we are in an error handling 2028 * procedure of an outgoing packet of our own, in which case we need 2029 * to search in the ifaddr list. 2030 */ 2031 if (IN6_IS_ADDR_MULTICAST(&origdst)) 2032 ; 2033 else if ((ip6a = ip6_getdstifaddr(m)) != NULL) { 2034 if ((ip6a->ip6a_flags & 2035 (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY)) == 0) 2036 src = &ip6a->ip6a_src; 2037 } else { 2038 union { 2039 struct sockaddr_in6 sin6; 2040 struct sockaddr sa; 2041 } u; 2042 2043 sockaddr_in6_init(&u.sin6, &origdst, 0, 0, 0); 2044 2045 ia = (struct in6_ifaddr *)ifa_ifwithaddr(&u.sa); 2046 2047 if (ia == NULL) 2048 ; 2049 else if ((ia->ia6_flags & 2050 (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY)) == 0) 2051 src = &ia->ia_addr.sin6_addr; 2052 } 2053 2054 if (src == NULL) { 2055 int e; 2056 struct sockaddr_in6 sin6; 2057 struct route ro; 2058 2059 /* 2060 * This case matches to multicasts, our anycast, or unicasts 2061 * that we do not own. Select a source address based on the 2062 * source address of the erroneous packet. 2063 */ 2064 /* zone ID should be embedded */ 2065 sockaddr_in6_init(&sin6, &ip6->ip6_dst, 0, 0, 0); 2066 2067 memset(&ro, 0, sizeof(ro)); 2068 src = in6_selectsrc(&sin6, NULL, NULL, &ro, NULL, &outif, &e); 2069 rtcache_free(&ro); 2070 if (src == NULL) { 2071 nd6log((LOG_DEBUG, 2072 "icmp6_reflect: source can't be determined: " 2073 "dst=%s, error=%d\n", 2074 ip6_sprintf(&sin6.sin6_addr), e)); 2075 goto bad; 2076 } 2077 } 2078 2079 ip6->ip6_src = *src; 2080 ip6->ip6_flow = 0; 2081 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2082 ip6->ip6_vfc |= IPV6_VERSION; 2083 ip6->ip6_nxt = IPPROTO_ICMPV6; 2084 if (m->m_pkthdr.rcvif) { 2085 /* XXX: This may not be the outgoing interface */ 2086 ip6->ip6_hlim = ND_IFINFO(m->m_pkthdr.rcvif)->chlim; 2087 } else 2088 ip6->ip6_hlim = ip6_defhlim; 2089 2090 m->m_pkthdr.csum_flags = 0; 2091 icmp6->icmp6_cksum = 0; 2092 icmp6->icmp6_cksum = in6_cksum(m, IPPROTO_ICMPV6, 2093 sizeof(struct ip6_hdr), plen); 2094 2095 /* 2096 * XXX option handling 2097 */ 2098 2099 m->m_flags &= ~(M_BCAST|M_MCAST); 2100 2101 /* 2102 * To avoid a "too big" situation at an intermediate router 2103 * and the path MTU discovery process, specify the IPV6_MINMTU flag. 2104 * Note that only echo and node information replies are affected, 2105 * since the length of ICMP6 errors is limited to the minimum MTU. 2106 */ 2107 if (ip6_output(m, NULL, NULL, IPV6_MINMTU, NULL, NULL, &outif) != 0 && 2108 outif) 2109 icmp6_ifstat_inc(outif, ifs6_out_error); 2110 2111 if (outif) 2112 icmp6_ifoutstat_inc(outif, type, code); 2113 2114 return; 2115 2116 bad: 2117 m_freem(m); 2118 return; 2119 } 2120 2121 static const char * 2122 icmp6_redirect_diag(struct in6_addr *src6, struct in6_addr *dst6, 2123 struct in6_addr *tgt6) 2124 { 2125 static char buf[1024]; 2126 snprintf(buf, sizeof(buf), "(src=%s dst=%s tgt=%s)", 2127 ip6_sprintf(src6), ip6_sprintf(dst6), ip6_sprintf(tgt6)); 2128 return buf; 2129 } 2130 2131 void 2132 icmp6_redirect_input(struct mbuf *m, int off) 2133 { 2134 struct ifnet *ifp = m->m_pkthdr.rcvif; 2135 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 2136 struct nd_redirect *nd_rd; 2137 int icmp6len = ntohs(ip6->ip6_plen); 2138 char *lladdr = NULL; 2139 int lladdrlen = 0; 2140 struct rtentry *rt = NULL; 2141 int is_router; 2142 int is_onlink; 2143 struct in6_addr src6 = ip6->ip6_src; 2144 struct in6_addr redtgt6; 2145 struct in6_addr reddst6; 2146 union nd_opts ndopts; 2147 2148 if (!ifp) 2149 return; 2150 2151 /* XXX if we are router, we don't update route by icmp6 redirect */ 2152 if (ip6_forwarding) 2153 goto freeit; 2154 if (!icmp6_rediraccept) 2155 goto freeit; 2156 2157 IP6_EXTHDR_GET(nd_rd, struct nd_redirect *, m, off, icmp6len); 2158 if (nd_rd == NULL) { 2159 ICMP6_STATINC(ICMP6_STAT_TOOSHORT); 2160 return; 2161 } 2162 redtgt6 = nd_rd->nd_rd_target; 2163 reddst6 = nd_rd->nd_rd_dst; 2164 2165 if (in6_setscope(&redtgt6, m->m_pkthdr.rcvif, NULL) || 2166 in6_setscope(&reddst6, m->m_pkthdr.rcvif, NULL)) { 2167 goto freeit; 2168 } 2169 2170 /* validation */ 2171 if (!IN6_IS_ADDR_LINKLOCAL(&src6)) { 2172 nd6log((LOG_ERR, 2173 "ICMP6 redirect sent from %s rejected; " 2174 "must be from linklocal\n", ip6_sprintf(&src6))); 2175 goto bad; 2176 } 2177 if (ip6->ip6_hlim != 255) { 2178 nd6log((LOG_ERR, 2179 "ICMP6 redirect sent from %s rejected; " 2180 "hlim=%d (must be 255)\n", 2181 ip6_sprintf(&src6), ip6->ip6_hlim)); 2182 goto bad; 2183 } 2184 { 2185 /* ip6->ip6_src must be equal to gw for icmp6->icmp6_reddst */ 2186 struct sockaddr_in6 sin6; 2187 struct in6_addr *gw6; 2188 2189 sockaddr_in6_init(&sin6, &reddst6, 0, 0, 0); 2190 rt = rtalloc1((struct sockaddr *)&sin6, 0); 2191 if (rt) { 2192 if (rt->rt_gateway == NULL || 2193 rt->rt_gateway->sa_family != AF_INET6) { 2194 nd6log((LOG_ERR, 2195 "ICMP6 redirect rejected; no route " 2196 "with inet6 gateway found for redirect dst: %s\n", 2197 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2198 RTFREE(rt); 2199 goto bad; 2200 } 2201 2202 gw6 = &(((struct sockaddr_in6 *)rt->rt_gateway)->sin6_addr); 2203 if (memcmp(&src6, gw6, sizeof(struct in6_addr)) != 0) { 2204 nd6log((LOG_ERR, 2205 "ICMP6 redirect rejected; " 2206 "not equal to gw-for-src=%s (must be same): " 2207 "%s\n", 2208 ip6_sprintf(gw6), 2209 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2210 RTFREE(rt); 2211 goto bad; 2212 } 2213 } else { 2214 nd6log((LOG_ERR, 2215 "ICMP6 redirect rejected; " 2216 "no route found for redirect dst: %s\n", 2217 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2218 goto bad; 2219 } 2220 RTFREE(rt); 2221 rt = NULL; 2222 } 2223 if (IN6_IS_ADDR_MULTICAST(&reddst6)) { 2224 nd6log((LOG_ERR, 2225 "ICMP6 redirect rejected; " 2226 "redirect dst must be unicast: %s\n", 2227 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2228 goto bad; 2229 } 2230 2231 is_router = is_onlink = 0; 2232 if (IN6_IS_ADDR_LINKLOCAL(&redtgt6)) 2233 is_router = 1; /* router case */ 2234 if (memcmp(&redtgt6, &reddst6, sizeof(redtgt6)) == 0) 2235 is_onlink = 1; /* on-link destination case */ 2236 if (!is_router && !is_onlink) { 2237 nd6log((LOG_ERR, 2238 "ICMP6 redirect rejected; " 2239 "neither router case nor onlink case: %s\n", 2240 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2241 goto bad; 2242 } 2243 /* validation passed */ 2244 2245 icmp6len -= sizeof(*nd_rd); 2246 nd6_option_init(nd_rd + 1, icmp6len, &ndopts); 2247 if (nd6_options(&ndopts) < 0) { 2248 nd6log((LOG_INFO, "icmp6_redirect_input: " 2249 "invalid ND option, rejected: %s\n", 2250 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2251 /* nd6_options have incremented stats */ 2252 goto freeit; 2253 } 2254 2255 if (ndopts.nd_opts_tgt_lladdr) { 2256 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 2257 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 2258 } 2259 2260 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 2261 nd6log((LOG_INFO, 2262 "icmp6_redirect_input: lladdrlen mismatch for %s " 2263 "(if %d, icmp6 packet %d): %s\n", 2264 ip6_sprintf(&redtgt6), ifp->if_addrlen, lladdrlen - 2, 2265 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2266 goto bad; 2267 } 2268 2269 /* RFC 2461 8.3 */ 2270 nd6_cache_lladdr(ifp, &redtgt6, lladdr, lladdrlen, ND_REDIRECT, 2271 is_onlink ? ND_REDIRECT_ONLINK : ND_REDIRECT_ROUTER); 2272 2273 if (!is_onlink) { /* better router case. perform rtredirect. */ 2274 /* perform rtredirect */ 2275 struct sockaddr_in6 sdst; 2276 struct sockaddr_in6 sgw; 2277 struct sockaddr_in6 ssrc; 2278 unsigned long rtcount; 2279 struct rtentry *newrt = NULL; 2280 2281 /* 2282 * do not install redirect route, if the number of entries 2283 * is too much (> hiwat). note that, the node (= host) will 2284 * work just fine even if we do not install redirect route 2285 * (there will be additional hops, though). 2286 */ 2287 rtcount = rt_timer_count(icmp6_redirect_timeout_q); 2288 if (0 <= icmp6_redirect_hiwat && rtcount > icmp6_redirect_hiwat) 2289 return; 2290 else if (0 <= icmp6_redirect_lowat && 2291 rtcount > icmp6_redirect_lowat) { 2292 /* 2293 * XXX nuke a victim, install the new one. 2294 */ 2295 } 2296 2297 memset(&sdst, 0, sizeof(sdst)); 2298 memset(&sgw, 0, sizeof(sgw)); 2299 memset(&ssrc, 0, sizeof(ssrc)); 2300 sdst.sin6_family = sgw.sin6_family = ssrc.sin6_family = AF_INET6; 2301 sdst.sin6_len = sgw.sin6_len = ssrc.sin6_len = 2302 sizeof(struct sockaddr_in6); 2303 bcopy(&redtgt6, &sgw.sin6_addr, sizeof(struct in6_addr)); 2304 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2305 bcopy(&src6, &ssrc.sin6_addr, sizeof(struct in6_addr)); 2306 rtredirect((struct sockaddr *)&sdst, (struct sockaddr *)&sgw, 2307 (struct sockaddr *)NULL, RTF_GATEWAY | RTF_HOST, 2308 (struct sockaddr *)&ssrc, 2309 &newrt); 2310 2311 if (newrt) { 2312 (void)rt_timer_add(newrt, icmp6_redirect_timeout, 2313 icmp6_redirect_timeout_q); 2314 rtfree(newrt); 2315 } 2316 } 2317 /* finally update cached route in each socket via pfctlinput */ 2318 { 2319 struct sockaddr_in6 sdst; 2320 2321 sockaddr_in6_init(&sdst, &reddst6, 0, 0, 0); 2322 pfctlinput(PRC_REDIRECT_HOST, (struct sockaddr *)&sdst); 2323 #if defined(IPSEC) || defined(FAST_IPSEC) 2324 key_sa_routechange((struct sockaddr *)&sdst); 2325 #endif 2326 } 2327 2328 freeit: 2329 m_freem(m); 2330 return; 2331 2332 bad: 2333 ICMP6_STATINC(ICMP6_STAT_BADREDIRECT); 2334 m_freem(m); 2335 } 2336 2337 void 2338 icmp6_redirect_output(struct mbuf *m0, struct rtentry *rt) 2339 { 2340 struct ifnet *ifp; /* my outgoing interface */ 2341 struct in6_addr *ifp_ll6; 2342 struct in6_addr *nexthop; 2343 struct ip6_hdr *sip6; /* m0 as struct ip6_hdr */ 2344 struct mbuf *m = NULL; /* newly allocated one */ 2345 struct ip6_hdr *ip6; /* m as struct ip6_hdr */ 2346 struct nd_redirect *nd_rd; 2347 size_t maxlen; 2348 u_char *p; 2349 struct sockaddr_in6 src_sa; 2350 2351 icmp6_errcount(ICMP6_STAT_OUTERRHIST, ND_REDIRECT, 0); 2352 2353 /* if we are not router, we don't send icmp6 redirect */ 2354 if (!ip6_forwarding) 2355 goto fail; 2356 2357 /* sanity check */ 2358 if (!m0 || !rt || !(rt->rt_flags & RTF_UP) || !(ifp = rt->rt_ifp)) 2359 goto fail; 2360 2361 /* 2362 * Address check: 2363 * the source address must identify a neighbor, and 2364 * the destination address must not be a multicast address 2365 * [RFC 2461, sec 8.2] 2366 */ 2367 sip6 = mtod(m0, struct ip6_hdr *); 2368 sockaddr_in6_init(&src_sa, &sip6->ip6_src, 0, 0, 0); 2369 if (nd6_is_addr_neighbor(&src_sa, ifp) == 0) 2370 goto fail; 2371 if (IN6_IS_ADDR_MULTICAST(&sip6->ip6_dst)) 2372 goto fail; /* what should we do here? */ 2373 2374 /* rate limit */ 2375 if (icmp6_ratelimit(&sip6->ip6_src, ND_REDIRECT, 0)) 2376 goto fail; 2377 2378 /* 2379 * Since we are going to append up to 1280 bytes (= IPV6_MMTU), 2380 * we almost always ask for an mbuf cluster for simplicity. 2381 * (MHLEN < IPV6_MMTU is almost always true) 2382 */ 2383 MGETHDR(m, M_DONTWAIT, MT_HEADER); 2384 if (m && IPV6_MMTU >= MHLEN) { 2385 #if IPV6_MMTU >= MCLBYTES 2386 _MCLGET(m, mcl_cache, IPV6_MMTU, M_DONTWAIT); 2387 #else 2388 MCLGET(m, M_DONTWAIT); 2389 #endif 2390 } 2391 2392 if (!m) 2393 goto fail; 2394 m->m_pkthdr.rcvif = NULL; 2395 m->m_len = 0; 2396 maxlen = M_TRAILINGSPACE(m); 2397 maxlen = min(IPV6_MMTU, maxlen); 2398 /* just for safety */ 2399 if (maxlen < sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) + 2400 ((sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7)) { 2401 goto fail; 2402 } 2403 2404 { 2405 /* get ip6 linklocal address for ifp(my outgoing interface). */ 2406 struct in6_ifaddr *ia; 2407 if ((ia = in6ifa_ifpforlinklocal(ifp, 2408 IN6_IFF_NOTREADY| 2409 IN6_IFF_ANYCAST)) == NULL) 2410 goto fail; 2411 ifp_ll6 = &ia->ia_addr.sin6_addr; 2412 } 2413 2414 /* get ip6 linklocal address for the router. */ 2415 if (rt->rt_gateway && (rt->rt_flags & RTF_GATEWAY)) { 2416 struct sockaddr_in6 *sin6; 2417 sin6 = (struct sockaddr_in6 *)rt->rt_gateway; 2418 nexthop = &sin6->sin6_addr; 2419 if (!IN6_IS_ADDR_LINKLOCAL(nexthop)) 2420 nexthop = NULL; 2421 } else 2422 nexthop = NULL; 2423 2424 /* ip6 */ 2425 ip6 = mtod(m, struct ip6_hdr *); 2426 ip6->ip6_flow = 0; 2427 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2428 ip6->ip6_vfc |= IPV6_VERSION; 2429 /* ip6->ip6_plen will be set later */ 2430 ip6->ip6_nxt = IPPROTO_ICMPV6; 2431 ip6->ip6_hlim = 255; 2432 /* ip6->ip6_src must be linklocal addr for my outgoing if. */ 2433 bcopy(ifp_ll6, &ip6->ip6_src, sizeof(struct in6_addr)); 2434 bcopy(&sip6->ip6_src, &ip6->ip6_dst, sizeof(struct in6_addr)); 2435 2436 /* ND Redirect */ 2437 nd_rd = (struct nd_redirect *)(ip6 + 1); 2438 nd_rd->nd_rd_type = ND_REDIRECT; 2439 nd_rd->nd_rd_code = 0; 2440 nd_rd->nd_rd_reserved = 0; 2441 if (rt->rt_flags & RTF_GATEWAY) { 2442 /* 2443 * nd_rd->nd_rd_target must be a link-local address in 2444 * better router cases. 2445 */ 2446 if (!nexthop) 2447 goto fail; 2448 bcopy(nexthop, &nd_rd->nd_rd_target, 2449 sizeof(nd_rd->nd_rd_target)); 2450 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2451 sizeof(nd_rd->nd_rd_dst)); 2452 } else { 2453 /* make sure redtgt == reddst */ 2454 nexthop = &sip6->ip6_dst; 2455 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_target, 2456 sizeof(nd_rd->nd_rd_target)); 2457 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2458 sizeof(nd_rd->nd_rd_dst)); 2459 } 2460 2461 p = (u_char *)(nd_rd + 1); 2462 2463 { 2464 /* target lladdr option */ 2465 struct rtentry *rt_nexthop = NULL; 2466 int len; 2467 const struct sockaddr_dl *sdl; 2468 struct nd_opt_hdr *nd_opt; 2469 char *lladdr; 2470 2471 rt_nexthop = nd6_lookup(nexthop, 0, ifp); 2472 if (!rt_nexthop) 2473 goto nolladdropt; 2474 len = sizeof(*nd_opt) + ifp->if_addrlen; 2475 len = (len + 7) & ~7; /* round by 8 */ 2476 /* safety check */ 2477 if (len + (p - (u_char *)ip6) > maxlen) 2478 goto nolladdropt; 2479 if (!(rt_nexthop->rt_flags & RTF_GATEWAY) && 2480 (rt_nexthop->rt_flags & RTF_LLINFO) && 2481 (rt_nexthop->rt_gateway->sa_family == AF_LINK) && 2482 (sdl = satocsdl(rt_nexthop->rt_gateway)) && 2483 sdl->sdl_alen) { 2484 nd_opt = (struct nd_opt_hdr *)p; 2485 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 2486 nd_opt->nd_opt_len = len >> 3; 2487 lladdr = (char *)(nd_opt + 1); 2488 memcpy(lladdr, CLLADDR(sdl), ifp->if_addrlen); 2489 p += len; 2490 } 2491 } 2492 nolladdropt:; 2493 2494 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2495 2496 /* just to be safe */ 2497 if (m0->m_flags & M_DECRYPTED) 2498 goto noredhdropt; 2499 if (p - (u_char *)ip6 > maxlen) 2500 goto noredhdropt; 2501 2502 { 2503 /* redirected header option */ 2504 int len; 2505 struct nd_opt_rd_hdr *nd_opt_rh; 2506 2507 /* 2508 * compute the maximum size for icmp6 redirect header option. 2509 * XXX room for auth header? 2510 */ 2511 len = maxlen - (p - (u_char *)ip6); 2512 len &= ~7; 2513 2514 /* 2515 * Redirected header option spec (RFC2461 4.6.3) talks nothing 2516 * about padding/truncate rule for the original IP packet. 2517 * From the discussion on IPv6imp in Feb 1999, 2518 * the consensus was: 2519 * - "attach as much as possible" is the goal 2520 * - pad if not aligned (original size can be guessed by 2521 * original ip6 header) 2522 * Following code adds the padding if it is simple enough, 2523 * and truncates if not. 2524 */ 2525 if (len - sizeof(*nd_opt_rh) < m0->m_pkthdr.len) { 2526 /* not enough room, truncate */ 2527 m_adj(m0, (len - sizeof(*nd_opt_rh)) - 2528 m0->m_pkthdr.len); 2529 } else { 2530 /* 2531 * enough room, truncate if not aligned. 2532 * we don't pad here for simplicity. 2533 */ 2534 size_t extra; 2535 2536 extra = m0->m_pkthdr.len % 8; 2537 if (extra) { 2538 /* truncate */ 2539 m_adj(m0, -extra); 2540 } 2541 len = m0->m_pkthdr.len + sizeof(*nd_opt_rh); 2542 } 2543 2544 nd_opt_rh = (struct nd_opt_rd_hdr *)p; 2545 memset(nd_opt_rh, 0, sizeof(*nd_opt_rh)); 2546 nd_opt_rh->nd_opt_rh_type = ND_OPT_REDIRECTED_HEADER; 2547 nd_opt_rh->nd_opt_rh_len = len >> 3; 2548 p += sizeof(*nd_opt_rh); 2549 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2550 2551 /* connect m0 to m */ 2552 m->m_pkthdr.len += m0->m_pkthdr.len; 2553 m_cat(m, m0); 2554 m0 = NULL; 2555 } 2556 noredhdropt: 2557 if (m0) { 2558 m_freem(m0); 2559 m0 = NULL; 2560 } 2561 2562 /* XXX: clear embedded link IDs in the inner header */ 2563 in6_clearscope(&sip6->ip6_src); 2564 in6_clearscope(&sip6->ip6_dst); 2565 in6_clearscope(&nd_rd->nd_rd_target); 2566 in6_clearscope(&nd_rd->nd_rd_dst); 2567 2568 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr)); 2569 2570 nd_rd->nd_rd_cksum = 0; 2571 nd_rd->nd_rd_cksum 2572 = in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), ntohs(ip6->ip6_plen)); 2573 2574 /* send the packet to outside... */ 2575 if (ip6_output(m, NULL, NULL, 0, 2576 (struct ip6_moptions *)NULL, (struct socket *)NULL, NULL) != 0) 2577 icmp6_ifstat_inc(ifp, ifs6_out_error); 2578 2579 icmp6_ifstat_inc(ifp, ifs6_out_msg); 2580 icmp6_ifstat_inc(ifp, ifs6_out_redirect); 2581 ICMP6_STATINC(ICMP6_STAT_OUTHIST + ND_REDIRECT); 2582 2583 return; 2584 2585 fail: 2586 if (m) 2587 m_freem(m); 2588 if (m0) 2589 m_freem(m0); 2590 } 2591 2592 /* 2593 * ICMPv6 socket option processing. 2594 */ 2595 int 2596 icmp6_ctloutput(int op, struct socket *so, struct sockopt *sopt) 2597 { 2598 int error = 0; 2599 struct in6pcb *in6p = sotoin6pcb(so); 2600 2601 if (sopt->sopt_level != IPPROTO_ICMPV6) 2602 return rip6_ctloutput(op, so, sopt); 2603 2604 switch (op) { 2605 case PRCO_SETOPT: 2606 switch (sopt->sopt_name) { 2607 case ICMP6_FILTER: 2608 { 2609 struct icmp6_filter fil; 2610 2611 error = sockopt_get(sopt, &fil, sizeof(fil)); 2612 if (error) 2613 break; 2614 memcpy(in6p->in6p_icmp6filt, &fil, 2615 sizeof(struct icmp6_filter)); 2616 error = 0; 2617 break; 2618 } 2619 2620 default: 2621 error = ENOPROTOOPT; 2622 break; 2623 } 2624 break; 2625 2626 case PRCO_GETOPT: 2627 switch (sopt->sopt_name) { 2628 case ICMP6_FILTER: 2629 { 2630 if (in6p->in6p_icmp6filt == NULL) { 2631 error = EINVAL; 2632 break; 2633 } 2634 error = sockopt_set(sopt, in6p->in6p_icmp6filt, 2635 sizeof(struct icmp6_filter)); 2636 break; 2637 } 2638 2639 default: 2640 error = ENOPROTOOPT; 2641 break; 2642 } 2643 break; 2644 } 2645 2646 return (error); 2647 } 2648 2649 /* 2650 * Perform rate limit check. 2651 * Returns 0 if it is okay to send the icmp6 packet. 2652 * Returns 1 if the router SHOULD NOT send this icmp6 packet due to rate 2653 * limitation. 2654 * 2655 * XXX per-destination/type check necessary? 2656 */ 2657 static int 2658 icmp6_ratelimit( 2659 const struct in6_addr *dst, /* not used at this moment */ 2660 const int type, /* not used at this moment */ 2661 const int code) /* not used at this moment */ 2662 { 2663 int ret; 2664 2665 ret = 0; /* okay to send */ 2666 2667 /* PPS limit */ 2668 if (!ppsratecheck(&icmp6errppslim_last, &icmp6errpps_count, 2669 icmp6errppslim)) { 2670 /* The packet is subject to rate limit */ 2671 ret++; 2672 } 2673 2674 return ret; 2675 } 2676 2677 static struct rtentry * 2678 icmp6_mtudisc_clone(struct sockaddr *dst) 2679 { 2680 struct rtentry *rt; 2681 int error; 2682 2683 rt = rtalloc1(dst, 1); 2684 if (rt == 0) 2685 return NULL; 2686 2687 /* If we didn't get a host route, allocate one */ 2688 if ((rt->rt_flags & RTF_HOST) == 0) { 2689 struct rtentry *nrt; 2690 2691 error = rtrequest((int) RTM_ADD, dst, 2692 (struct sockaddr *) rt->rt_gateway, 2693 (struct sockaddr *) 0, 2694 RTF_GATEWAY | RTF_HOST | RTF_DYNAMIC, &nrt); 2695 if (error) { 2696 rtfree(rt); 2697 return NULL; 2698 } 2699 nrt->rt_rmx = rt->rt_rmx; 2700 rtfree(rt); 2701 rt = nrt; 2702 } 2703 error = rt_timer_add(rt, icmp6_mtudisc_timeout, 2704 icmp6_mtudisc_timeout_q); 2705 if (error) { 2706 rtfree(rt); 2707 return NULL; 2708 } 2709 2710 return rt; /* caller need to call rtfree() */ 2711 } 2712 2713 static void 2714 icmp6_mtudisc_timeout(struct rtentry *rt, struct rttimer *r) 2715 { 2716 if (rt == NULL) 2717 panic("icmp6_mtudisc_timeout: bad route to timeout"); 2718 if ((rt->rt_flags & (RTF_DYNAMIC | RTF_HOST)) == 2719 (RTF_DYNAMIC | RTF_HOST)) { 2720 rtrequest((int) RTM_DELETE, rt_getkey(rt), 2721 rt->rt_gateway, rt_mask(rt), rt->rt_flags, 0); 2722 } else { 2723 if (!(rt->rt_rmx.rmx_locks & RTV_MTU)) 2724 rt->rt_rmx.rmx_mtu = 0; 2725 } 2726 } 2727 2728 static void 2729 icmp6_redirect_timeout(struct rtentry *rt, struct rttimer *r) 2730 { 2731 if (rt == NULL) 2732 panic("icmp6_redirect_timeout: bad route to timeout"); 2733 if ((rt->rt_flags & (RTF_GATEWAY | RTF_DYNAMIC | RTF_HOST)) == 2734 (RTF_GATEWAY | RTF_DYNAMIC | RTF_HOST)) { 2735 rtrequest((int) RTM_DELETE, rt_getkey(rt), 2736 rt->rt_gateway, rt_mask(rt), rt->rt_flags, 0); 2737 } 2738 } 2739 2740 /* 2741 * sysctl helper routine for the net.inet6.icmp6.nd6 nodes. silly? 2742 */ 2743 static int 2744 sysctl_net_inet6_icmp6_nd6(SYSCTLFN_ARGS) 2745 { 2746 (void)&name; 2747 (void)&l; 2748 (void)&oname; 2749 2750 if (namelen != 0) 2751 return (EINVAL); 2752 2753 return (nd6_sysctl(rnode->sysctl_num, oldp, oldlenp, 2754 /*XXXUNCONST*/ 2755 __UNCONST(newp), newlen)); 2756 } 2757 2758 static int 2759 sysctl_net_inet6_icmp6_stats(SYSCTLFN_ARGS) 2760 { 2761 2762 return (NETSTAT_SYSCTL(icmp6stat_percpu, ICMP6_NSTATS)); 2763 } 2764 2765 static void 2766 sysctl_net_inet6_icmp6_setup(struct sysctllog **clog) 2767 { 2768 extern int nd6_maxqueuelen; /* defined in nd6.c */ 2769 2770 sysctl_createv(clog, 0, NULL, NULL, 2771 CTLFLAG_PERMANENT, 2772 CTLTYPE_NODE, "net", NULL, 2773 NULL, 0, NULL, 0, 2774 CTL_NET, CTL_EOL); 2775 sysctl_createv(clog, 0, NULL, NULL, 2776 CTLFLAG_PERMANENT, 2777 CTLTYPE_NODE, "inet6", NULL, 2778 NULL, 0, NULL, 0, 2779 CTL_NET, PF_INET6, CTL_EOL); 2780 sysctl_createv(clog, 0, NULL, NULL, 2781 CTLFLAG_PERMANENT, 2782 CTLTYPE_NODE, "icmp6", 2783 SYSCTL_DESCR("ICMPv6 related settings"), 2784 NULL, 0, NULL, 0, 2785 CTL_NET, PF_INET6, IPPROTO_ICMPV6, CTL_EOL); 2786 2787 sysctl_createv(clog, 0, NULL, NULL, 2788 CTLFLAG_PERMANENT, 2789 CTLTYPE_STRUCT, "stats", 2790 SYSCTL_DESCR("ICMPv6 transmission statistics"), 2791 sysctl_net_inet6_icmp6_stats, 0, NULL, 0, 2792 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2793 ICMPV6CTL_STATS, CTL_EOL); 2794 sysctl_createv(clog, 0, NULL, NULL, 2795 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2796 CTLTYPE_INT, "rediraccept", 2797 SYSCTL_DESCR("Accept and process redirect messages"), 2798 NULL, 0, &icmp6_rediraccept, 0, 2799 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2800 ICMPV6CTL_REDIRACCEPT, CTL_EOL); 2801 sysctl_createv(clog, 0, NULL, NULL, 2802 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2803 CTLTYPE_INT, "redirtimeout", 2804 SYSCTL_DESCR("Redirect generated route lifetime"), 2805 NULL, 0, &icmp6_redirtimeout, 0, 2806 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2807 ICMPV6CTL_REDIRTIMEOUT, CTL_EOL); 2808 #if 0 /* obsoleted */ 2809 sysctl_createv(clog, 0, NULL, NULL, 2810 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2811 CTLTYPE_INT, "errratelimit", NULL, 2812 NULL, 0, &icmp6_errratelimit, 0, 2813 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2814 ICMPV6CTL_ERRRATELIMIT, CTL_EOL); 2815 #endif 2816 sysctl_createv(clog, 0, NULL, NULL, 2817 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2818 CTLTYPE_INT, "nd6_prune", 2819 SYSCTL_DESCR("Neighbor discovery prune interval"), 2820 NULL, 0, &nd6_prune, 0, 2821 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2822 ICMPV6CTL_ND6_PRUNE, CTL_EOL); 2823 sysctl_createv(clog, 0, NULL, NULL, 2824 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2825 CTLTYPE_INT, "nd6_delay", 2826 SYSCTL_DESCR("First probe delay time"), 2827 NULL, 0, &nd6_delay, 0, 2828 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2829 ICMPV6CTL_ND6_DELAY, CTL_EOL); 2830 sysctl_createv(clog, 0, NULL, NULL, 2831 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2832 CTLTYPE_INT, "nd6_umaxtries", 2833 SYSCTL_DESCR("Number of unicast discovery attempts"), 2834 NULL, 0, &nd6_umaxtries, 0, 2835 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2836 ICMPV6CTL_ND6_UMAXTRIES, CTL_EOL); 2837 sysctl_createv(clog, 0, NULL, NULL, 2838 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2839 CTLTYPE_INT, "nd6_mmaxtries", 2840 SYSCTL_DESCR("Number of multicast discovery attempts"), 2841 NULL, 0, &nd6_mmaxtries, 0, 2842 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2843 ICMPV6CTL_ND6_MMAXTRIES, CTL_EOL); 2844 sysctl_createv(clog, 0, NULL, NULL, 2845 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2846 CTLTYPE_INT, "nd6_useloopback", 2847 SYSCTL_DESCR("Use loopback interface for local traffic"), 2848 NULL, 0, &nd6_useloopback, 0, 2849 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2850 ICMPV6CTL_ND6_USELOOPBACK, CTL_EOL); 2851 #if 0 /* obsoleted */ 2852 sysctl_createv(clog, 0, NULL, NULL, 2853 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2854 CTLTYPE_INT, "nd6_proxyall", NULL, 2855 NULL, 0, &nd6_proxyall, 0, 2856 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2857 ICMPV6CTL_ND6_PROXYALL, CTL_EOL); 2858 #endif 2859 sysctl_createv(clog, 0, NULL, NULL, 2860 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2861 CTLTYPE_INT, "nodeinfo", 2862 SYSCTL_DESCR("Respond to node information requests"), 2863 NULL, 0, &icmp6_nodeinfo, 0, 2864 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2865 ICMPV6CTL_NODEINFO, CTL_EOL); 2866 sysctl_createv(clog, 0, NULL, NULL, 2867 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2868 CTLTYPE_INT, "errppslimit", 2869 SYSCTL_DESCR("Maximum ICMP errors sent per second"), 2870 NULL, 0, &icmp6errppslim, 0, 2871 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2872 ICMPV6CTL_ERRPPSLIMIT, CTL_EOL); 2873 sysctl_createv(clog, 0, NULL, NULL, 2874 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2875 CTLTYPE_INT, "nd6_maxnudhint", 2876 SYSCTL_DESCR("Maximum neighbor unreachable hint count"), 2877 NULL, 0, &nd6_maxnudhint, 0, 2878 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2879 ICMPV6CTL_ND6_MAXNUDHINT, CTL_EOL); 2880 sysctl_createv(clog, 0, NULL, NULL, 2881 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2882 CTLTYPE_INT, "mtudisc_hiwat", 2883 SYSCTL_DESCR("Low mark on MTU Discovery route timers"), 2884 NULL, 0, &icmp6_mtudisc_hiwat, 0, 2885 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2886 ICMPV6CTL_MTUDISC_HIWAT, CTL_EOL); 2887 sysctl_createv(clog, 0, NULL, NULL, 2888 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2889 CTLTYPE_INT, "mtudisc_lowat", 2890 SYSCTL_DESCR("Low mark on MTU Discovery route timers"), 2891 NULL, 0, &icmp6_mtudisc_lowat, 0, 2892 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2893 ICMPV6CTL_MTUDISC_LOWAT, CTL_EOL); 2894 sysctl_createv(clog, 0, NULL, NULL, 2895 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2896 CTLTYPE_INT, "nd6_debug", 2897 SYSCTL_DESCR("Enable neighbor discovery debug output"), 2898 NULL, 0, &nd6_debug, 0, 2899 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2900 ICMPV6CTL_ND6_DEBUG, CTL_EOL); 2901 sysctl_createv(clog, 0, NULL, NULL, 2902 CTLFLAG_PERMANENT, 2903 CTLTYPE_STRUCT, "nd6_drlist", 2904 SYSCTL_DESCR("Default router list"), 2905 sysctl_net_inet6_icmp6_nd6, 0, NULL, 0, 2906 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2907 ICMPV6CTL_ND6_DRLIST, CTL_EOL); 2908 sysctl_createv(clog, 0, NULL, NULL, 2909 CTLFLAG_PERMANENT, 2910 CTLTYPE_STRUCT, "nd6_prlist", 2911 SYSCTL_DESCR("Prefix list"), 2912 sysctl_net_inet6_icmp6_nd6, 0, NULL, 0, 2913 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2914 ICMPV6CTL_ND6_PRLIST, CTL_EOL); 2915 sysctl_createv(clog, 0, NULL, NULL, 2916 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 2917 CTLTYPE_INT, "maxqueuelen", 2918 SYSCTL_DESCR("max packet queue len for a unresolved ND"), 2919 NULL, 1, &nd6_maxqueuelen, 0, 2920 CTL_NET, PF_INET6, IPPROTO_ICMPV6, 2921 ICMPV6CTL_ND6_MAXQLEN, CTL_EOL); 2922 } 2923 2924 void 2925 icmp6_statinc(u_int stat) 2926 { 2927 2928 KASSERT(stat < ICMP6_NSTATS); 2929 ICMP6_STATINC(stat); 2930 } 2931
Indexes created Tue Sep 23 23:09:58 GMT 2025