1 /* $NetBSD: icmp6.c,v 1.94 2003/06/24 07:54:47 itojun 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. All advertising materials mentioning features or use of this software 46 * must display the following acknowledgement: 47 * This product includes software developed by the University of 48 * California, Berkeley and its contributors. 49 * 4. Neither the name of the University nor the names of its contributors 50 * may be used to endorse or promote products derived from this software 51 * without specific prior written permission. 52 * 53 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 54 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 55 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 56 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 57 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 58 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 59 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 60 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 61 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 62 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 63 * SUCH DAMAGE. 64 * 65 * @(#)ip_icmp.c 8.2 (Berkeley) 1/4/94 66 */ 67 68 #include <sys/cdefs.h> 69 __KERNEL_RCSID(0, "$NetBSD: icmp6.c,v 1.94 2003/06/24 07:54:47 itojun Exp $"); 70 71 #include "opt_inet.h" 72 #include "opt_ipsec.h" 73 74 #include <sys/param.h> 75 #include <sys/systm.h> 76 #include <sys/malloc.h> 77 #include <sys/mbuf.h> 78 #include <sys/protosw.h> 79 #include <sys/socket.h> 80 #include <sys/socketvar.h> 81 #include <sys/time.h> 82 #include <sys/kernel.h> 83 #include <sys/syslog.h> 84 #include <sys/domain.h> 85 #include <sys/sysctl.h> 86 87 #include <net/if.h> 88 #include <net/route.h> 89 #include <net/if_dl.h> 90 #include <net/if_types.h> 91 92 #include <netinet/in.h> 93 #include <netinet/in_var.h> 94 #include <netinet/ip6.h> 95 #include <netinet6/ip6_var.h> 96 #include <netinet/icmp6.h> 97 #include <netinet6/mld6_var.h> 98 #include <netinet6/in6_pcb.h> 99 #include <netinet6/nd6.h> 100 #include <netinet6/in6_ifattach.h> 101 #include <netinet6/ip6protosw.h> 102 103 #ifdef IPSEC 104 #include <netinet6/ipsec.h> 105 #include <netkey/key.h> 106 #endif 107 108 #include "faith.h" 109 #if defined(NFAITH) && 0 < NFAITH 110 #include <net/if_faith.h> 111 #endif 112 113 #include <net/net_osdep.h> 114 115 extern struct domain inet6domain; 116 117 struct icmp6stat icmp6stat; 118 119 extern struct in6pcb rawin6pcb; 120 extern int icmp6errppslim; 121 static int icmp6errpps_count = 0; 122 static struct timeval icmp6errppslim_last; 123 extern int icmp6_nodeinfo; 124 125 /* 126 * List of callbacks to notify when Path MTU changes are made. 127 */ 128 struct icmp6_mtudisc_callback { 129 LIST_ENTRY(icmp6_mtudisc_callback) mc_list; 130 void (*mc_func) __P((struct in6_addr *)); 131 }; 132 133 LIST_HEAD(, icmp6_mtudisc_callback) icmp6_mtudisc_callbacks = 134 LIST_HEAD_INITIALIZER(&icmp6_mtudisc_callbacks); 135 136 static struct rttimer_queue *icmp6_mtudisc_timeout_q = NULL; 137 extern int pmtu_expire; 138 139 /* XXX do these values make any sense? */ 140 static int icmp6_mtudisc_hiwat = 1280; 141 static int icmp6_mtudisc_lowat = 256; 142 143 /* 144 * keep track of # of redirect routes. 145 */ 146 static struct rttimer_queue *icmp6_redirect_timeout_q = NULL; 147 148 /* XXX experimental, turned off */ 149 static int icmp6_redirect_hiwat = -1; 150 static int icmp6_redirect_lowat = -1; 151 152 static void icmp6_errcount __P((struct icmp6errstat *, int, int)); 153 static int icmp6_rip6_input __P((struct mbuf **, int)); 154 static int icmp6_ratelimit __P((const struct in6_addr *, const int, const int)); 155 static const char *icmp6_redirect_diag __P((struct in6_addr *, 156 struct in6_addr *, struct in6_addr *)); 157 static struct mbuf *ni6_input __P((struct mbuf *, int)); 158 static struct mbuf *ni6_nametodns __P((const char *, int, int)); 159 static int ni6_dnsmatch __P((const char *, int, const char *, int)); 160 static int ni6_addrs __P((struct icmp6_nodeinfo *, struct mbuf *, 161 struct ifnet **, char *)); 162 static int ni6_store_addrs __P((struct icmp6_nodeinfo *, struct icmp6_nodeinfo *, 163 struct ifnet *, int)); 164 static int icmp6_notify_error __P((struct mbuf *, int, int, int)); 165 static struct rtentry *icmp6_mtudisc_clone __P((struct sockaddr *)); 166 static void icmp6_mtudisc_timeout __P((struct rtentry *, struct rttimer *)); 167 static void icmp6_redirect_timeout __P((struct rtentry *, struct rttimer *)); 168 169 void 170 icmp6_init() 171 { 172 mld6_init(); 173 icmp6_mtudisc_timeout_q = rt_timer_queue_create(pmtu_expire); 174 icmp6_redirect_timeout_q = rt_timer_queue_create(icmp6_redirtimeout); 175 } 176 177 static void 178 icmp6_errcount(stat, type, code) 179 struct icmp6errstat *stat; 180 int type, code; 181 { 182 switch (type) { 183 case ICMP6_DST_UNREACH: 184 switch (code) { 185 case ICMP6_DST_UNREACH_NOROUTE: 186 stat->icp6errs_dst_unreach_noroute++; 187 return; 188 case ICMP6_DST_UNREACH_ADMIN: 189 stat->icp6errs_dst_unreach_admin++; 190 return; 191 case ICMP6_DST_UNREACH_BEYONDSCOPE: 192 stat->icp6errs_dst_unreach_beyondscope++; 193 return; 194 case ICMP6_DST_UNREACH_ADDR: 195 stat->icp6errs_dst_unreach_addr++; 196 return; 197 case ICMP6_DST_UNREACH_NOPORT: 198 stat->icp6errs_dst_unreach_noport++; 199 return; 200 } 201 break; 202 case ICMP6_PACKET_TOO_BIG: 203 stat->icp6errs_packet_too_big++; 204 return; 205 case ICMP6_TIME_EXCEEDED: 206 switch (code) { 207 case ICMP6_TIME_EXCEED_TRANSIT: 208 stat->icp6errs_time_exceed_transit++; 209 return; 210 case ICMP6_TIME_EXCEED_REASSEMBLY: 211 stat->icp6errs_time_exceed_reassembly++; 212 return; 213 } 214 break; 215 case ICMP6_PARAM_PROB: 216 switch (code) { 217 case ICMP6_PARAMPROB_HEADER: 218 stat->icp6errs_paramprob_header++; 219 return; 220 case ICMP6_PARAMPROB_NEXTHEADER: 221 stat->icp6errs_paramprob_nextheader++; 222 return; 223 case ICMP6_PARAMPROB_OPTION: 224 stat->icp6errs_paramprob_option++; 225 return; 226 } 227 break; 228 case ND_REDIRECT: 229 stat->icp6errs_redirect++; 230 return; 231 } 232 stat->icp6errs_unknown++; 233 } 234 235 /* 236 * Register a Path MTU Discovery callback. 237 */ 238 void 239 icmp6_mtudisc_callback_register(func) 240 void (*func) __P((struct in6_addr *)); 241 { 242 struct icmp6_mtudisc_callback *mc; 243 244 for (mc = LIST_FIRST(&icmp6_mtudisc_callbacks); mc != NULL; 245 mc = LIST_NEXT(mc, mc_list)) { 246 if (mc->mc_func == func) 247 return; 248 } 249 250 mc = malloc(sizeof(*mc), M_PCB, M_NOWAIT); 251 if (mc == NULL) 252 panic("icmp6_mtudisc_callback_register"); 253 254 mc->mc_func = func; 255 LIST_INSERT_HEAD(&icmp6_mtudisc_callbacks, mc, mc_list); 256 } 257 258 /* 259 * Generate an error packet of type error in response to bad IP6 packet. 260 */ 261 void 262 icmp6_error(m, type, code, param) 263 struct mbuf *m; 264 int type, code, param; 265 { 266 struct ip6_hdr *oip6, *nip6; 267 struct icmp6_hdr *icmp6; 268 u_int preplen; 269 int off; 270 int nxt; 271 272 icmp6stat.icp6s_error++; 273 274 /* count per-type-code statistics */ 275 icmp6_errcount(&icmp6stat.icp6s_outerrhist, type, code); 276 277 if (m->m_flags & M_DECRYPTED) { 278 icmp6stat.icp6s_canterror++; 279 goto freeit; 280 } 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 oip6 = mtod(m, struct ip6_hdr *); 288 289 /* 290 * If the destination address of the erroneous packet is a multicast 291 * address, or the packet was sent using link-layer multicast, 292 * we should basically suppress sending an error (RFC 2463, Section 293 * 2.4). 294 * We have two exceptions (the item e.2 in that section): 295 * - the Pakcet Too Big message can be sent for path MTU discovery. 296 * - the Parameter Problem Message that can be allowed an icmp6 error 297 * in the option type field. This check has been done in 298 * ip6_unknown_opt(), so we can just check the type and code. 299 */ 300 if ((m->m_flags & (M_BCAST|M_MCAST) || 301 IN6_IS_ADDR_MULTICAST(&oip6->ip6_dst)) && 302 (type != ICMP6_PACKET_TOO_BIG && 303 (type != ICMP6_PARAM_PROB || 304 code != ICMP6_PARAMPROB_OPTION))) 305 goto freeit; 306 307 /* 308 * RFC 2463, 2.4 (e.5): source address check. 309 * XXX: the case of anycast source? 310 */ 311 if (IN6_IS_ADDR_UNSPECIFIED(&oip6->ip6_src) || 312 IN6_IS_ADDR_MULTICAST(&oip6->ip6_src)) 313 goto freeit; 314 315 /* 316 * If we are about to send ICMPv6 against ICMPv6 error/redirect, 317 * don't do it. 318 */ 319 nxt = -1; 320 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); 321 if (off >= 0 && nxt == IPPROTO_ICMPV6) { 322 struct icmp6_hdr *icp; 323 324 IP6_EXTHDR_GET(icp, struct icmp6_hdr *, m, off, 325 sizeof(*icp)); 326 if (icp == NULL) { 327 icmp6stat.icp6s_tooshort++; 328 return; 329 } 330 if (icp->icmp6_type < ICMP6_ECHO_REQUEST || 331 icp->icmp6_type == ND_REDIRECT) { 332 /* 333 * ICMPv6 error 334 * Special case: for redirect (which is 335 * informational) we must not send icmp6 error. 336 */ 337 icmp6stat.icp6s_canterror++; 338 goto freeit; 339 } else { 340 /* ICMPv6 informational - send the error */ 341 } 342 } 343 #if 0 /* controversial */ 344 else if (off >= 0 && nxt == IPPROTO_ESP) { 345 /* 346 * It could be ICMPv6 error inside ESP. Take a safer side, 347 * don't respond. 348 */ 349 icmp6stat.icp6s_canterror++; 350 goto freeit; 351 } 352 #endif 353 else { 354 /* non-ICMPv6 - send the error */ 355 } 356 357 oip6 = mtod(m, struct ip6_hdr *); /* adjust pointer */ 358 359 /* Finally, do rate limitation check. */ 360 if (icmp6_ratelimit(&oip6->ip6_src, type, code)) { 361 icmp6stat.icp6s_toofreq++; 362 goto freeit; 363 } 364 365 /* 366 * OK, ICMP6 can be generated. 367 */ 368 369 if (m->m_pkthdr.len >= ICMPV6_PLD_MAXLEN) 370 m_adj(m, ICMPV6_PLD_MAXLEN - m->m_pkthdr.len); 371 372 preplen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 373 M_PREPEND(m, preplen, M_DONTWAIT); 374 if (m && m->m_len < preplen) 375 m = m_pullup(m, preplen); 376 if (m == NULL) { 377 nd6log((LOG_DEBUG, "ENOBUFS in icmp6_error %d\n", __LINE__)); 378 return; 379 } 380 381 nip6 = mtod(m, struct ip6_hdr *); 382 nip6->ip6_src = oip6->ip6_src; 383 nip6->ip6_dst = oip6->ip6_dst; 384 385 if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_src)) 386 oip6->ip6_src.s6_addr16[1] = 0; 387 if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_dst)) 388 oip6->ip6_dst.s6_addr16[1] = 0; 389 390 icmp6 = (struct icmp6_hdr *)(nip6 + 1); 391 icmp6->icmp6_type = type; 392 icmp6->icmp6_code = code; 393 icmp6->icmp6_pptr = htonl((u_int32_t)param); 394 395 /* 396 * icmp6_reflect() is designed to be in the input path. 397 * icmp6_error() can be called from both input and outut path, 398 * and if we are in output path rcvif could contain bogus value. 399 * clear m->m_pkthdr.rcvif for safety, we should have enough scope 400 * information in ip header (nip6). 401 */ 402 m->m_pkthdr.rcvif = NULL; 403 404 icmp6stat.icp6s_outhist[type]++; 405 icmp6_reflect(m, sizeof(struct ip6_hdr)); /* header order: IPv6 - ICMPv6 */ 406 407 return; 408 409 freeit: 410 /* 411 * If we can't tell wheter or not we can generate ICMP6, free it. 412 */ 413 m_freem(m); 414 } 415 416 /* 417 * Process a received ICMP6 message. 418 */ 419 int 420 icmp6_input(mp, offp, proto) 421 struct mbuf **mp; 422 int *offp, proto; 423 { 424 struct mbuf *m = *mp, *n; 425 struct ip6_hdr *ip6, *nip6; 426 struct icmp6_hdr *icmp6, *nicmp6; 427 int off = *offp; 428 int icmp6len = m->m_pkthdr.len - *offp; 429 int code, sum, noff; 430 431 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_msg); 432 433 /* 434 * Locate icmp6 structure in mbuf, and check 435 * that not corrupted and of at least minimum length 436 */ 437 438 ip6 = mtod(m, struct ip6_hdr *); 439 if (icmp6len < sizeof(struct icmp6_hdr)) { 440 icmp6stat.icp6s_tooshort++; 441 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_error); 442 goto freeit; 443 } 444 445 /* 446 * calculate the checksum 447 */ 448 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 449 if (icmp6 == NULL) { 450 icmp6stat.icp6s_tooshort++; 451 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_error); 452 return IPPROTO_DONE; 453 } 454 KASSERT(IP6_HDR_ALIGNED_P(icmp6)); 455 code = icmp6->icmp6_code; 456 457 if ((sum = in6_cksum(m, IPPROTO_ICMPV6, off, icmp6len)) != 0) { 458 nd6log((LOG_ERR, 459 "ICMP6 checksum error(%d|%x) %s\n", 460 icmp6->icmp6_type, sum, ip6_sprintf(&ip6->ip6_src))); 461 icmp6stat.icp6s_checksum++; 462 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_error); 463 goto freeit; 464 } 465 466 #if defined(NFAITH) && 0 < NFAITH 467 if (faithprefix(&ip6->ip6_dst)) { 468 /* 469 * Deliver very specific ICMP6 type only. 470 * This is important to deilver TOOBIG. Otherwise PMTUD 471 * will not work. 472 */ 473 switch (icmp6->icmp6_type) { 474 case ICMP6_DST_UNREACH: 475 case ICMP6_PACKET_TOO_BIG: 476 case ICMP6_TIME_EXCEEDED: 477 break; 478 default: 479 goto freeit; 480 } 481 } 482 #endif 483 484 icmp6stat.icp6s_inhist[icmp6->icmp6_type]++; 485 486 switch (icmp6->icmp6_type) { 487 case ICMP6_DST_UNREACH: 488 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_dstunreach); 489 switch (code) { 490 case ICMP6_DST_UNREACH_NOROUTE: 491 code = PRC_UNREACH_NET; 492 break; 493 case ICMP6_DST_UNREACH_ADMIN: 494 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_adminprohib); 495 code = PRC_UNREACH_PROTOCOL; /* is this a good code? */ 496 break; 497 case ICMP6_DST_UNREACH_ADDR: 498 code = PRC_HOSTDEAD; 499 break; 500 #ifdef COMPAT_RFC1885 501 case ICMP6_DST_UNREACH_NOTNEIGHBOR: 502 code = PRC_UNREACH_SRCFAIL; 503 break; 504 #else 505 case ICMP6_DST_UNREACH_BEYONDSCOPE: 506 /* I mean "source address was incorrect." */ 507 code = PRC_UNREACH_NET; 508 break; 509 #endif 510 case ICMP6_DST_UNREACH_NOPORT: 511 code = PRC_UNREACH_PORT; 512 break; 513 default: 514 goto badcode; 515 } 516 goto deliver; 517 518 case ICMP6_PACKET_TOO_BIG: 519 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_pkttoobig); 520 if (code != 0) 521 goto badcode; 522 523 code = PRC_MSGSIZE; 524 525 /* 526 * Updating the path MTU will be done after examining 527 * intermediate extension headers. 528 */ 529 goto deliver; 530 531 case ICMP6_TIME_EXCEEDED: 532 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_timeexceed); 533 switch (code) { 534 case ICMP6_TIME_EXCEED_TRANSIT: 535 code = PRC_TIMXCEED_INTRANS; 536 break; 537 case ICMP6_TIME_EXCEED_REASSEMBLY: 538 code = PRC_TIMXCEED_REASS; 539 break; 540 default: 541 goto badcode; 542 } 543 goto deliver; 544 545 case ICMP6_PARAM_PROB: 546 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_paramprob); 547 switch (code) { 548 case ICMP6_PARAMPROB_NEXTHEADER: 549 code = PRC_UNREACH_PROTOCOL; 550 break; 551 case ICMP6_PARAMPROB_HEADER: 552 case ICMP6_PARAMPROB_OPTION: 553 code = PRC_PARAMPROB; 554 break; 555 default: 556 goto badcode; 557 } 558 goto deliver; 559 560 case ICMP6_ECHO_REQUEST: 561 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echo); 562 if (code != 0) 563 goto badcode; 564 /* 565 * Copy mbuf to send to two data paths: userland socket(s), 566 * and to the querier (echo reply). 567 * m: a copy for socket, n: a copy for querier 568 */ 569 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 570 /* Give up local */ 571 n = m; 572 m = NULL; 573 goto deliverecho; 574 } 575 /* 576 * If the first mbuf is shared, or the first mbuf is too short, 577 * copy the first part of the data into a fresh mbuf. 578 * Otherwise, we will wrongly overwrite both copies. 579 */ 580 if ((n->m_flags & M_EXT) != 0 || 581 n->m_len < off + sizeof(struct icmp6_hdr)) { 582 struct mbuf *n0 = n; 583 const int maxlen = sizeof(*nip6) + sizeof(*nicmp6); 584 585 /* 586 * Prepare an internal mbuf. m_pullup() doesn't 587 * always copy the length we specified. 588 */ 589 if (maxlen >= MCLBYTES) { 590 /* Give up remote */ 591 m_freem(n0); 592 break; 593 } 594 MGETHDR(n, M_DONTWAIT, n0->m_type); 595 if (n && maxlen >= MHLEN) { 596 MCLGET(n, M_DONTWAIT); 597 if ((n->m_flags & M_EXT) == 0) { 598 m_free(n); 599 n = NULL; 600 } 601 } 602 if (n == NULL) { 603 /* Give up local */ 604 m_freem(n0); 605 n = m; 606 m = NULL; 607 goto deliverecho; 608 } 609 M_COPY_PKTHDR(n, n0); 610 /* 611 * Copy IPv6 and ICMPv6 only. 612 */ 613 nip6 = mtod(n, struct ip6_hdr *); 614 bcopy(ip6, nip6, sizeof(struct ip6_hdr)); 615 nicmp6 = (struct icmp6_hdr *)(nip6 + 1); 616 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr)); 617 noff = sizeof(struct ip6_hdr); 618 n->m_len = noff + sizeof(struct icmp6_hdr); 619 /* 620 * Adjust mbuf. ip6_plen will be adjusted in 621 * ip6_output(). 622 * n->m_pkthdr.len == n0->m_pkthdr.len at this point. 623 */ 624 n->m_pkthdr.len += noff + sizeof(struct icmp6_hdr); 625 n->m_pkthdr.len -= (off + sizeof(struct icmp6_hdr)); 626 m_adj(n0, off + sizeof(struct icmp6_hdr)); 627 n->m_next = n0; 628 n0->m_flags &= ~M_PKTHDR; 629 } else { 630 deliverecho: 631 nip6 = mtod(n, struct ip6_hdr *); 632 nicmp6 = (struct icmp6_hdr *)((caddr_t)nip6 + off); 633 noff = off; 634 } 635 nicmp6->icmp6_type = ICMP6_ECHO_REPLY; 636 nicmp6->icmp6_code = 0; 637 if (n) { 638 icmp6stat.icp6s_reflect++; 639 icmp6stat.icp6s_outhist[ICMP6_ECHO_REPLY]++; 640 icmp6_reflect(n, noff); 641 } 642 if (!m) 643 goto freeit; 644 break; 645 646 case ICMP6_ECHO_REPLY: 647 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echoreply); 648 if (code != 0) 649 goto badcode; 650 break; 651 652 case MLD_LISTENER_QUERY: 653 case MLD_LISTENER_REPORT: 654 if (icmp6len < sizeof(struct mld_hdr)) 655 goto badlen; 656 if (icmp6->icmp6_type == MLD_LISTENER_QUERY) /* XXX: ugly... */ 657 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldquery); 658 else 659 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldreport); 660 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 661 /* give up local */ 662 mld6_input(m, off); 663 m = NULL; 664 goto freeit; 665 } 666 mld6_input(n, off); 667 /* m stays. */ 668 break; 669 670 case MLD_LISTENER_DONE: 671 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mlddone); 672 if (icmp6len < sizeof(struct mld_hdr)) /* necessary? */ 673 goto badlen; 674 break; /* nothing to be done in kernel */ 675 676 case MLD_MTRACE_RESP: 677 case MLD_MTRACE: 678 /* XXX: these two are experimental. not officially defined. */ 679 /* XXX: per-interface statistics? */ 680 break; /* just pass it to applications */ 681 682 case ICMP6_WRUREQUEST: /* ICMP6_FQDN_QUERY */ 683 { 684 enum { WRU, FQDN } mode; 685 686 if (!icmp6_nodeinfo) 687 break; 688 689 if (icmp6len == sizeof(struct icmp6_hdr) + 4) 690 mode = WRU; 691 else if (icmp6len >= sizeof(struct icmp6_nodeinfo)) 692 mode = FQDN; 693 else 694 goto badlen; 695 696 if (mode == FQDN) { 697 n = m_copym(m, 0, M_COPYALL, M_DONTWAIT); 698 if (n) 699 n = ni6_input(n, off); 700 /* XXX meaningless if n == NULL */ 701 noff = sizeof(struct ip6_hdr); 702 } else { 703 u_char *p; 704 int maxlen, maxhlen; 705 706 if ((icmp6_nodeinfo & 5) != 5) 707 break; 708 709 if (code != 0) 710 goto badcode; 711 maxlen = sizeof(*nip6) + sizeof(*nicmp6) + 4; 712 if (maxlen >= MCLBYTES) { 713 /* Give up remote */ 714 break; 715 } 716 MGETHDR(n, M_DONTWAIT, m->m_type); 717 if (n && maxlen > MHLEN) { 718 MCLGET(n, M_DONTWAIT); 719 if ((n->m_flags & M_EXT) == 0) { 720 m_free(n); 721 n = NULL; 722 } 723 } 724 if (n == NULL) { 725 /* Give up remote */ 726 break; 727 } 728 n->m_pkthdr.rcvif = NULL; 729 n->m_len = 0; 730 maxhlen = M_TRAILINGSPACE(n) - maxlen; 731 if (maxhlen > hostnamelen) 732 maxhlen = hostnamelen; 733 /* 734 * Copy IPv6 and ICMPv6 only. 735 */ 736 nip6 = mtod(n, struct ip6_hdr *); 737 bcopy(ip6, nip6, sizeof(struct ip6_hdr)); 738 nicmp6 = (struct icmp6_hdr *)(nip6 + 1); 739 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr)); 740 p = (u_char *)(nicmp6 + 1); 741 bzero(p, 4); 742 bcopy(hostname, p + 4, maxhlen); /* meaningless TTL */ 743 noff = sizeof(struct ip6_hdr); 744 M_COPY_PKTHDR(n, m); /* just for rcvif */ 745 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) + 746 sizeof(struct icmp6_hdr) + 4 + maxhlen; 747 nicmp6->icmp6_type = ICMP6_WRUREPLY; 748 nicmp6->icmp6_code = 0; 749 } 750 #undef hostnamelen 751 if (n) { 752 icmp6stat.icp6s_reflect++; 753 icmp6stat.icp6s_outhist[ICMP6_WRUREPLY]++; 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 icmp6stat.icp6s_badcode++; 875 break; 876 877 badlen: 878 icmp6stat.icp6s_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(m, off, icmp6len, code) 894 struct mbuf *m; 895 int off, icmp6len; 896 { 897 struct icmp6_hdr *icmp6; 898 struct ip6_hdr *eip6; 899 u_int32_t notifymtu; 900 struct sockaddr_in6 icmp6src, icmp6dst; 901 902 if (icmp6len < sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr)) { 903 icmp6stat.icp6s_tooshort++; 904 goto freeit; 905 } 906 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, 907 sizeof(*icmp6) + sizeof(struct ip6_hdr)); 908 if (icmp6 == NULL) { 909 icmp6stat.icp6s_tooshort++; 910 return (-1); 911 } 912 eip6 = (struct ip6_hdr *)(icmp6 + 1); 913 914 /* Detect the upper level protocol */ 915 { 916 void (*ctlfunc) __P((int, struct sockaddr *, void *)); 917 u_int8_t nxt = eip6->ip6_nxt; 918 int eoff = off + sizeof(struct icmp6_hdr) + 919 sizeof(struct ip6_hdr); 920 struct ip6ctlparam ip6cp; 921 struct in6_addr *finaldst = NULL; 922 int icmp6type = icmp6->icmp6_type; 923 struct ip6_frag *fh; 924 struct ip6_rthdr *rth; 925 struct ip6_rthdr0 *rth0; 926 int rthlen; 927 928 while (1) { /* XXX: should avoid infinite loop explicitly? */ 929 struct ip6_ext *eh; 930 931 switch (nxt) { 932 case IPPROTO_HOPOPTS: 933 case IPPROTO_DSTOPTS: 934 case IPPROTO_AH: 935 IP6_EXTHDR_GET(eh, struct ip6_ext *, m, 936 eoff, sizeof(*eh)); 937 if (eh == NULL) { 938 icmp6stat.icp6s_tooshort++; 939 return (-1); 940 } 941 942 if (nxt == IPPROTO_AH) 943 eoff += (eh->ip6e_len + 2) << 2; 944 else 945 eoff += (eh->ip6e_len + 1) << 3; 946 nxt = eh->ip6e_nxt; 947 break; 948 case IPPROTO_ROUTING: 949 /* 950 * When the erroneous packet contains a 951 * routing header, we should examine the 952 * header to determine the final destination. 953 * Otherwise, we can't properly update 954 * information that depends on the final 955 * destination (e.g. path MTU). 956 */ 957 IP6_EXTHDR_GET(rth, struct ip6_rthdr *, m, 958 eoff, sizeof(*rth)); 959 if (rth == NULL) { 960 icmp6stat.icp6s_tooshort++; 961 return (-1); 962 } 963 rthlen = (rth->ip6r_len + 1) << 3; 964 /* 965 * XXX: currently there is no 966 * officially defined type other 967 * than type-0. 968 * Note that if the segment left field 969 * is 0, all intermediate hops must 970 * have been passed. 971 */ 972 if (rth->ip6r_segleft && 973 rth->ip6r_type == IPV6_RTHDR_TYPE_0) { 974 int hops; 975 976 IP6_EXTHDR_GET(rth0, 977 struct ip6_rthdr0 *, m, 978 eoff, rthlen); 979 if (rth0 == NULL) { 980 icmp6stat.icp6s_tooshort++; 981 return (-1); 982 } 983 /* just ignore a bogus header */ 984 if ((rth0->ip6r0_len % 2) == 0 && 985 (hops = rth0->ip6r0_len/2)) 986 finaldst = (struct in6_addr *)(rth0 + 1) + (hops - 1); 987 } 988 eoff += rthlen; 989 nxt = rth->ip6r_nxt; 990 break; 991 case IPPROTO_FRAGMENT: 992 IP6_EXTHDR_GET(fh, struct ip6_frag *, m, 993 eoff, sizeof(*fh)); 994 if (fh == NULL) { 995 icmp6stat.icp6s_tooshort++; 996 return (-1); 997 } 998 /* 999 * Data after a fragment header is meaningless 1000 * unless it is the first fragment, but 1001 * we'll go to the notify label for path MTU 1002 * discovery. 1003 */ 1004 if (fh->ip6f_offlg & IP6F_OFF_MASK) 1005 goto notify; 1006 1007 eoff += sizeof(struct ip6_frag); 1008 nxt = fh->ip6f_nxt; 1009 break; 1010 default: 1011 /* 1012 * This case includes ESP and the No Next 1013 * Header. In such cases going to the notify 1014 * label does not have any meaning 1015 * (i.e. ctlfunc will be NULL), but we go 1016 * anyway since we might have to update 1017 * path MTU information. 1018 */ 1019 goto notify; 1020 } 1021 } 1022 notify: 1023 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, 1024 sizeof(*icmp6) + sizeof(struct ip6_hdr)); 1025 if (icmp6 == NULL) { 1026 icmp6stat.icp6s_tooshort++; 1027 return (-1); 1028 } 1029 1030 eip6 = (struct ip6_hdr *)(icmp6 + 1); 1031 bzero(&icmp6dst, sizeof(icmp6dst)); 1032 icmp6dst.sin6_len = sizeof(struct sockaddr_in6); 1033 icmp6dst.sin6_family = AF_INET6; 1034 if (finaldst == NULL) 1035 icmp6dst.sin6_addr = eip6->ip6_dst; 1036 else 1037 icmp6dst.sin6_addr = *finaldst; 1038 icmp6dst.sin6_scope_id = in6_addr2scopeid(m->m_pkthdr.rcvif, 1039 &icmp6dst.sin6_addr); 1040 #ifndef SCOPEDROUTING 1041 if (in6_embedscope(&icmp6dst.sin6_addr, &icmp6dst, 1042 NULL, NULL)) { 1043 /* should be impossbile */ 1044 nd6log((LOG_DEBUG, 1045 "icmp6_notify_error: in6_embedscope failed\n")); 1046 goto freeit; 1047 } 1048 #endif 1049 1050 /* 1051 * retrieve parameters from the inner IPv6 header, and convert 1052 * them into sockaddr structures. 1053 */ 1054 bzero(&icmp6src, sizeof(icmp6src)); 1055 icmp6src.sin6_len = sizeof(struct sockaddr_in6); 1056 icmp6src.sin6_family = AF_INET6; 1057 icmp6src.sin6_addr = eip6->ip6_src; 1058 icmp6src.sin6_scope_id = in6_addr2scopeid(m->m_pkthdr.rcvif, 1059 &icmp6src.sin6_addr); 1060 #ifndef SCOPEDROUTING 1061 if (in6_embedscope(&icmp6src.sin6_addr, &icmp6src, 1062 NULL, NULL)) { 1063 /* should be impossbile */ 1064 nd6log((LOG_DEBUG, 1065 "icmp6_notify_error: in6_embedscope failed\n")); 1066 goto freeit; 1067 } 1068 #endif 1069 icmp6src.sin6_flowinfo = 1070 (eip6->ip6_flow & IPV6_FLOWLABEL_MASK); 1071 1072 if (finaldst == NULL) 1073 finaldst = &eip6->ip6_dst; 1074 ip6cp.ip6c_m = m; 1075 ip6cp.ip6c_icmp6 = icmp6; 1076 ip6cp.ip6c_ip6 = (struct ip6_hdr *)(icmp6 + 1); 1077 ip6cp.ip6c_off = eoff; 1078 ip6cp.ip6c_finaldst = finaldst; 1079 ip6cp.ip6c_src = &icmp6src; 1080 ip6cp.ip6c_nxt = nxt; 1081 1082 if (icmp6type == ICMP6_PACKET_TOO_BIG) { 1083 notifymtu = ntohl(icmp6->icmp6_mtu); 1084 ip6cp.ip6c_cmdarg = (void *)¬ifymtu; 1085 } 1086 1087 ctlfunc = (void (*) __P((int, struct sockaddr *, void *))) 1088 (inet6sw[ip6_protox[nxt]].pr_ctlinput); 1089 if (ctlfunc) { 1090 (void) (*ctlfunc)(code, (struct sockaddr *)&icmp6dst, 1091 &ip6cp); 1092 } 1093 } 1094 return (0); 1095 1096 freeit: 1097 m_freem(m); 1098 return (-1); 1099 } 1100 1101 void 1102 icmp6_mtudisc_update(ip6cp, validated) 1103 struct ip6ctlparam *ip6cp; 1104 int validated; 1105 { 1106 unsigned long rtcount; 1107 struct icmp6_mtudisc_callback *mc; 1108 struct in6_addr *dst = ip6cp->ip6c_finaldst; 1109 struct icmp6_hdr *icmp6 = ip6cp->ip6c_icmp6; 1110 struct mbuf *m = ip6cp->ip6c_m; /* will be necessary for scope issue */ 1111 u_int mtu = ntohl(icmp6->icmp6_mtu); 1112 struct rtentry *rt = NULL; 1113 struct sockaddr_in6 sin6; 1114 1115 /* 1116 * allow non-validated cases if memory is plenty, to make traffic 1117 * from non-connected pcb happy. 1118 */ 1119 rtcount = rt_timer_count(icmp6_mtudisc_timeout_q); 1120 if (validated) { 1121 if (0 <= icmp6_mtudisc_hiwat && rtcount > icmp6_mtudisc_hiwat) 1122 return; 1123 else if (0 <= icmp6_mtudisc_lowat && 1124 rtcount > icmp6_mtudisc_lowat) { 1125 /* 1126 * XXX nuke a victim, install the new one. 1127 */ 1128 } 1129 } else { 1130 if (0 <= icmp6_mtudisc_lowat && rtcount > icmp6_mtudisc_lowat) 1131 return; 1132 } 1133 1134 bzero(&sin6, sizeof(sin6)); 1135 sin6.sin6_family = PF_INET6; 1136 sin6.sin6_len = sizeof(struct sockaddr_in6); 1137 sin6.sin6_addr = *dst; 1138 /* XXX normally, this won't happen */ 1139 if (IN6_IS_ADDR_LINKLOCAL(dst)) { 1140 sin6.sin6_addr.s6_addr16[1] = 1141 htons(m->m_pkthdr.rcvif->if_index); 1142 } 1143 /* sin6.sin6_scope_id = XXX: should be set if DST is a scoped addr */ 1144 rt = icmp6_mtudisc_clone((struct sockaddr *)&sin6); 1145 1146 if (rt && (rt->rt_flags & RTF_HOST) && 1147 !(rt->rt_rmx.rmx_locks & RTV_MTU) && 1148 (rt->rt_rmx.rmx_mtu > mtu || rt->rt_rmx.rmx_mtu == 0)) { 1149 if (mtu < IN6_LINKMTU(rt->rt_ifp)) { 1150 icmp6stat.icp6s_pmtuchg++; 1151 rt->rt_rmx.rmx_mtu = mtu; 1152 } 1153 } 1154 if (rt) { /* XXX: need braces to avoid conflict with else in RTFREE. */ 1155 RTFREE(rt); 1156 } 1157 1158 /* 1159 * Notify protocols that the MTU for this destination 1160 * has changed. 1161 */ 1162 for (mc = LIST_FIRST(&icmp6_mtudisc_callbacks); mc != NULL; 1163 mc = LIST_NEXT(mc, mc_list)) 1164 (*mc->mc_func)(&sin6.sin6_addr); 1165 } 1166 1167 /* 1168 * Process a Node Information Query packet, based on 1169 * draft-ietf-ipngwg-icmp-name-lookups-07. 1170 * 1171 * Spec incompatibilities: 1172 * - IPv6 Subject address handling 1173 * - IPv4 Subject address handling support missing 1174 * - Proxy reply (answer even if it's not for me) 1175 * - joins NI group address at in6_ifattach() time only, does not cope 1176 * with hostname changes by sethostname(3) 1177 */ 1178 #ifndef offsetof /* XXX */ 1179 #define offsetof(type, member) ((size_t)(&((type *)0)->member)) 1180 #endif 1181 static struct mbuf * 1182 ni6_input(m, off) 1183 struct mbuf *m; 1184 int off; 1185 { 1186 struct icmp6_nodeinfo *ni6, *nni6; 1187 struct mbuf *n = NULL; 1188 u_int16_t qtype; 1189 int subjlen; 1190 int replylen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo); 1191 struct ni_reply_fqdn *fqdn; 1192 int addrs; /* for NI_QTYPE_NODEADDR */ 1193 struct ifnet *ifp = NULL; /* for NI_QTYPE_NODEADDR */ 1194 struct sockaddr_in6 sin6; /* double meaning; ip6_dst and subjectaddr */ 1195 struct ip6_hdr *ip6; 1196 int oldfqdn = 0; /* if 1, return pascal string (03 draft) */ 1197 char *subj = NULL; 1198 1199 ip6 = mtod(m, struct ip6_hdr *); 1200 IP6_EXTHDR_GET(ni6, struct icmp6_nodeinfo *, m, off, sizeof(*ni6)); 1201 if (ni6 == NULL) { 1202 /* m is already reclaimed */ 1203 return NULL; 1204 } 1205 1206 /* 1207 * Validate IPv6 destination address. 1208 * 1209 * The Responder must discard the Query without further processing 1210 * unless it is one of the Responder's unicast or anycast addresses, or 1211 * a link-local scope multicast address which the Responder has joined. 1212 * [icmp-name-lookups-07, Section 4.] 1213 */ 1214 bzero(&sin6, sizeof(sin6)); 1215 sin6.sin6_family = AF_INET6; 1216 sin6.sin6_len = sizeof(struct sockaddr_in6); 1217 bcopy(&ip6->ip6_dst, &sin6.sin6_addr, sizeof(sin6.sin6_addr)); 1218 /* XXX scopeid */ 1219 if (ifa_ifwithaddr((struct sockaddr *)&sin6)) 1220 ; /* unicast/anycast, fine */ 1221 else if (IN6_IS_ADDR_MC_LINKLOCAL(&sin6.sin6_addr)) 1222 ; /* link-local multicast, fine */ 1223 else 1224 goto bad; 1225 1226 /* validate query Subject field. */ 1227 qtype = ntohs(ni6->ni_qtype); 1228 subjlen = m->m_pkthdr.len - off - sizeof(struct icmp6_nodeinfo); 1229 switch (qtype) { 1230 case NI_QTYPE_NOOP: 1231 case NI_QTYPE_SUPTYPES: 1232 /* 07 draft */ 1233 if (ni6->ni_code == ICMP6_NI_SUBJ_FQDN && subjlen == 0) 1234 break; 1235 /* FALLTHROUGH */ 1236 case NI_QTYPE_FQDN: 1237 case NI_QTYPE_NODEADDR: 1238 switch (ni6->ni_code) { 1239 case ICMP6_NI_SUBJ_IPV6: 1240 #if ICMP6_NI_SUBJ_IPV6 != 0 1241 case 0: 1242 #endif 1243 /* 1244 * backward compatibility - try to accept 03 draft 1245 * format, where no Subject is present. 1246 */ 1247 if (qtype == NI_QTYPE_FQDN && ni6->ni_code == 0 && 1248 subjlen == 0) { 1249 oldfqdn++; 1250 break; 1251 } 1252 #if ICMP6_NI_SUBJ_IPV6 != 0 1253 if (ni6->ni_code != ICMP6_NI_SUBJ_IPV6) 1254 goto bad; 1255 #endif 1256 1257 if (subjlen != sizeof(sin6.sin6_addr)) 1258 goto bad; 1259 1260 /* 1261 * Validate Subject address. 1262 * 1263 * Not sure what exactly "address belongs to the node" 1264 * means in the spec, is it just unicast, or what? 1265 * 1266 * At this moment we consider Subject address as 1267 * "belong to the node" if the Subject address equals 1268 * to the IPv6 destination address; validation for 1269 * IPv6 destination address should have done enough 1270 * check for us. 1271 * 1272 * We do not do proxy at this moment. 1273 */ 1274 /* m_pulldown instead of copy? */ 1275 m_copydata(m, off + sizeof(struct icmp6_nodeinfo), 1276 subjlen, (caddr_t)&sin6.sin6_addr); 1277 /* XXX kame scope hack */ 1278 if (IN6_IS_SCOPE_LINKLOCAL(&sin6.sin6_addr)) { 1279 if ((m->m_flags & M_PKTHDR) != 0 && 1280 m->m_pkthdr.rcvif) { 1281 sin6.sin6_addr.s6_addr16[1] = 1282 htons(m->m_pkthdr.rcvif->if_index); 1283 } 1284 } 1285 subj = (char *)&sin6; 1286 if (IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, &sin6.sin6_addr)) 1287 break; 1288 1289 /* 1290 * XXX if we are to allow other cases, we should really 1291 * be careful about scope here. 1292 * basically, we should disallow queries toward IPv6 1293 * destination X with subject Y, if scope(X) > scope(Y). 1294 * if we allow scope(X) > scope(Y), it will result in 1295 * information leakage across scope boundary. 1296 */ 1297 goto bad; 1298 1299 case ICMP6_NI_SUBJ_FQDN: 1300 /* 1301 * Validate Subject name with gethostname(3). 1302 * 1303 * The behavior may need some debate, since: 1304 * - we are not sure if the node has FQDN as 1305 * hostname (returned by gethostname(3)). 1306 * - the code does wildcard match for truncated names. 1307 * however, we are not sure if we want to perform 1308 * wildcard match, if gethostname(3) side has 1309 * truncated hostname. 1310 */ 1311 n = ni6_nametodns(hostname, hostnamelen, 0); 1312 if (!n || n->m_next || n->m_len == 0) 1313 goto bad; 1314 IP6_EXTHDR_GET(subj, char *, m, 1315 off + sizeof(struct icmp6_nodeinfo), subjlen); 1316 if (subj == NULL) 1317 goto bad; 1318 if (!ni6_dnsmatch(subj, subjlen, mtod(n, const char *), 1319 n->m_len)) { 1320 goto bad; 1321 } 1322 m_freem(n); 1323 n = NULL; 1324 break; 1325 1326 case ICMP6_NI_SUBJ_IPV4: /* XXX: to be implemented? */ 1327 default: 1328 goto bad; 1329 } 1330 break; 1331 } 1332 1333 /* refuse based on configuration. XXX ICMP6_NI_REFUSED? */ 1334 switch (qtype) { 1335 case NI_QTYPE_FQDN: 1336 if ((icmp6_nodeinfo & 1) == 0) 1337 goto bad; 1338 break; 1339 case NI_QTYPE_NODEADDR: 1340 if ((icmp6_nodeinfo & 2) == 0) 1341 goto bad; 1342 break; 1343 } 1344 1345 /* guess reply length */ 1346 switch (qtype) { 1347 case NI_QTYPE_NOOP: 1348 break; /* no reply data */ 1349 case NI_QTYPE_SUPTYPES: 1350 replylen += sizeof(u_int32_t); 1351 break; 1352 case NI_QTYPE_FQDN: 1353 /* XXX will append an mbuf */ 1354 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1355 break; 1356 case NI_QTYPE_NODEADDR: 1357 addrs = ni6_addrs(ni6, m, &ifp, subj); 1358 if ((replylen += addrs * (sizeof(struct in6_addr) + 1359 sizeof(u_int32_t))) > MCLBYTES) 1360 replylen = MCLBYTES; /* XXX: will truncate pkt later */ 1361 break; 1362 default: 1363 /* 1364 * XXX: We must return a reply with the ICMP6 code 1365 * `unknown Qtype' in this case. However we regard the case 1366 * as an FQDN query for backward compatibility. 1367 * Older versions set a random value to this field, 1368 * so it rarely varies in the defined qtypes. 1369 * But the mechanism is not reliable... 1370 * maybe we should obsolete older versions. 1371 */ 1372 qtype = NI_QTYPE_FQDN; 1373 /* XXX will append an mbuf */ 1374 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1375 oldfqdn++; 1376 break; 1377 } 1378 1379 /* allocate an mbuf to reply. */ 1380 MGETHDR(n, M_DONTWAIT, m->m_type); 1381 if (n == NULL) { 1382 m_freem(m); 1383 return (NULL); 1384 } 1385 M_COPY_PKTHDR(n, m); /* just for rcvif */ 1386 if (replylen > MHLEN) { 1387 if (replylen > MCLBYTES) { 1388 /* 1389 * XXX: should we try to allocate more? But MCLBYTES 1390 * is probably much larger than IPV6_MMTU... 1391 */ 1392 goto bad; 1393 } 1394 MCLGET(n, M_DONTWAIT); 1395 if ((n->m_flags & M_EXT) == 0) { 1396 goto bad; 1397 } 1398 } 1399 n->m_pkthdr.len = n->m_len = replylen; 1400 1401 /* copy mbuf header and IPv6 + Node Information base headers */ 1402 bcopy(mtod(m, caddr_t), mtod(n, caddr_t), sizeof(struct ip6_hdr)); 1403 nni6 = (struct icmp6_nodeinfo *)(mtod(n, struct ip6_hdr *) + 1); 1404 bcopy((caddr_t)ni6, (caddr_t)nni6, sizeof(struct icmp6_nodeinfo)); 1405 1406 /* qtype dependent procedure */ 1407 switch (qtype) { 1408 case NI_QTYPE_NOOP: 1409 nni6->ni_code = ICMP6_NI_SUCCESS; 1410 nni6->ni_flags = 0; 1411 break; 1412 case NI_QTYPE_SUPTYPES: 1413 { 1414 u_int32_t v; 1415 nni6->ni_code = ICMP6_NI_SUCCESS; 1416 nni6->ni_flags = htons(0x0000); /* raw bitmap */ 1417 /* supports NOOP, SUPTYPES, FQDN, and NODEADDR */ 1418 v = (u_int32_t)htonl(0x0000000f); 1419 bcopy(&v, nni6 + 1, sizeof(u_int32_t)); 1420 break; 1421 } 1422 case NI_QTYPE_FQDN: 1423 nni6->ni_code = ICMP6_NI_SUCCESS; 1424 fqdn = (struct ni_reply_fqdn *)(mtod(n, caddr_t) + 1425 sizeof(struct ip6_hdr) + 1426 sizeof(struct icmp6_nodeinfo)); 1427 nni6->ni_flags = 0; /* XXX: meaningless TTL */ 1428 fqdn->ni_fqdn_ttl = 0; /* ditto. */ 1429 /* 1430 * XXX do we really have FQDN in variable "hostname"? 1431 */ 1432 n->m_next = ni6_nametodns(hostname, hostnamelen, oldfqdn); 1433 if (n->m_next == NULL) 1434 goto bad; 1435 /* XXX we assume that n->m_next is not a chain */ 1436 if (n->m_next->m_next != NULL) 1437 goto bad; 1438 n->m_pkthdr.len += n->m_next->m_len; 1439 break; 1440 case NI_QTYPE_NODEADDR: 1441 { 1442 int lenlim, copied; 1443 1444 nni6->ni_code = ICMP6_NI_SUCCESS; 1445 n->m_pkthdr.len = n->m_len = 1446 sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo); 1447 lenlim = M_TRAILINGSPACE(n); 1448 copied = ni6_store_addrs(ni6, nni6, ifp, lenlim); 1449 /* XXX: reset mbuf length */ 1450 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) + 1451 sizeof(struct icmp6_nodeinfo) + copied; 1452 break; 1453 } 1454 default: 1455 break; /* XXX impossible! */ 1456 } 1457 1458 nni6->ni_type = ICMP6_NI_REPLY; 1459 m_freem(m); 1460 return (n); 1461 1462 bad: 1463 m_freem(m); 1464 if (n) 1465 m_freem(n); 1466 return (NULL); 1467 } 1468 #undef hostnamelen 1469 1470 #define isupper(x) ('A' <= (x) && (x) <= 'Z') 1471 #define isalpha(x) (('A' <= (x) && (x) <= 'Z') || ('a' <= (x) && (x) <= 'z')) 1472 #define isalnum(x) (isalpha(x) || ('0' <= (x) && (x) <= '9')) 1473 #define tolower(x) (isupper(x) ? (x) + 'a' - 'A' : (x)) 1474 1475 /* 1476 * make a mbuf with DNS-encoded string. no compression support. 1477 * 1478 * XXX names with less than 2 dots (like "foo" or "foo.section") will be 1479 * treated as truncated name (two \0 at the end). this is a wild guess. 1480 */ 1481 static struct mbuf * 1482 ni6_nametodns(name, namelen, old) 1483 const char *name; 1484 int namelen; 1485 int old; /* return pascal string if non-zero */ 1486 { 1487 struct mbuf *m; 1488 char *cp, *ep; 1489 const char *p, *q; 1490 int i, len, nterm; 1491 1492 if (old) 1493 len = namelen + 1; 1494 else 1495 len = MCLBYTES; 1496 1497 /* because MAXHOSTNAMELEN is usually 256, we use cluster mbuf */ 1498 MGET(m, M_DONTWAIT, MT_DATA); 1499 if (m && len > MLEN) { 1500 MCLGET(m, M_DONTWAIT); 1501 if ((m->m_flags & M_EXT) == 0) 1502 goto fail; 1503 } 1504 if (!m) 1505 goto fail; 1506 m->m_next = NULL; 1507 1508 if (old) { 1509 m->m_len = len; 1510 *mtod(m, char *) = namelen; 1511 bcopy(name, mtod(m, char *) + 1, namelen); 1512 return m; 1513 } else { 1514 m->m_len = 0; 1515 cp = mtod(m, char *); 1516 ep = mtod(m, char *) + M_TRAILINGSPACE(m); 1517 1518 /* if not certain about my name, return empty buffer */ 1519 if (namelen == 0) 1520 return m; 1521 1522 /* 1523 * guess if it looks like shortened hostname, or FQDN. 1524 * shortened hostname needs two trailing "\0". 1525 */ 1526 i = 0; 1527 for (p = name; p < name + namelen; p++) { 1528 if (*p && *p == '.') 1529 i++; 1530 } 1531 if (i < 2) 1532 nterm = 2; 1533 else 1534 nterm = 1; 1535 1536 p = name; 1537 while (cp < ep && p < name + namelen) { 1538 i = 0; 1539 for (q = p; q < name + namelen && *q && *q != '.'; q++) 1540 i++; 1541 /* result does not fit into mbuf */ 1542 if (cp + i + 1 >= ep) 1543 goto fail; 1544 /* 1545 * DNS label length restriction, RFC1035 page 8. 1546 * "i == 0" case is included here to avoid returning 1547 * 0-length label on "foo..bar". 1548 */ 1549 if (i <= 0 || i >= 64) 1550 goto fail; 1551 *cp++ = i; 1552 if (!isalpha(p[0]) || !isalnum(p[i - 1])) 1553 goto fail; 1554 while (i > 0) { 1555 if (!isalnum(*p) && *p != '-') 1556 goto fail; 1557 if (isupper(*p)) { 1558 *cp++ = tolower(*p); 1559 p++; 1560 } else 1561 *cp++ = *p++; 1562 i--; 1563 } 1564 p = q; 1565 if (p < name + namelen && *p == '.') 1566 p++; 1567 } 1568 /* termination */ 1569 if (cp + nterm >= ep) 1570 goto fail; 1571 while (nterm-- > 0) 1572 *cp++ = '\0'; 1573 m->m_len = cp - mtod(m, char *); 1574 return m; 1575 } 1576 1577 panic("should not reach here"); 1578 /* NOTREACHED */ 1579 1580 fail: 1581 if (m) 1582 m_freem(m); 1583 return NULL; 1584 } 1585 1586 /* 1587 * check if two DNS-encoded string matches. takes care of truncated 1588 * form (with \0\0 at the end). no compression support. 1589 * XXX upper/lowercase match (see RFC2065) 1590 */ 1591 static int 1592 ni6_dnsmatch(a, alen, b, blen) 1593 const char *a; 1594 int alen; 1595 const char *b; 1596 int blen; 1597 { 1598 const char *a0, *b0; 1599 int l; 1600 1601 /* simplest case - need validation? */ 1602 if (alen == blen && bcmp(a, b, alen) == 0) 1603 return 1; 1604 1605 a0 = a; 1606 b0 = b; 1607 1608 /* termination is mandatory */ 1609 if (alen < 2 || blen < 2) 1610 return 0; 1611 if (a0[alen - 1] != '\0' || b0[blen - 1] != '\0') 1612 return 0; 1613 alen--; 1614 blen--; 1615 1616 while (a - a0 < alen && b - b0 < blen) { 1617 if (a - a0 + 1 > alen || b - b0 + 1 > blen) 1618 return 0; 1619 1620 if ((signed char)a[0] < 0 || (signed char)b[0] < 0) 1621 return 0; 1622 /* we don't support compression yet */ 1623 if (a[0] >= 64 || b[0] >= 64) 1624 return 0; 1625 1626 /* truncated case */ 1627 if (a[0] == 0 && a - a0 == alen - 1) 1628 return 1; 1629 if (b[0] == 0 && b - b0 == blen - 1) 1630 return 1; 1631 if (a[0] == 0 || b[0] == 0) 1632 return 0; 1633 1634 if (a[0] != b[0]) 1635 return 0; 1636 l = a[0]; 1637 if (a - a0 + 1 + l > alen || b - b0 + 1 + l > blen) 1638 return 0; 1639 if (bcmp(a + 1, b + 1, l) != 0) 1640 return 0; 1641 1642 a += 1 + l; 1643 b += 1 + l; 1644 } 1645 1646 if (a - a0 == alen && b - b0 == blen) 1647 return 1; 1648 else 1649 return 0; 1650 } 1651 1652 /* 1653 * calculate the number of addresses to be returned in the node info reply. 1654 */ 1655 static int 1656 ni6_addrs(ni6, m, ifpp, subj) 1657 struct icmp6_nodeinfo *ni6; 1658 struct mbuf *m; 1659 struct ifnet **ifpp; 1660 char *subj; 1661 { 1662 struct ifnet *ifp; 1663 struct in6_ifaddr *ifa6; 1664 struct ifaddr *ifa; 1665 struct sockaddr_in6 *subj_ip6 = NULL; /* XXX pedant */ 1666 int addrs = 0, addrsofif, iffound = 0; 1667 int niflags = ni6->ni_flags; 1668 1669 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0) { 1670 switch (ni6->ni_code) { 1671 case ICMP6_NI_SUBJ_IPV6: 1672 if (subj == NULL) /* must be impossible... */ 1673 return (0); 1674 subj_ip6 = (struct sockaddr_in6 *)subj; 1675 break; 1676 default: 1677 /* 1678 * XXX: we only support IPv6 subject address for 1679 * this Qtype. 1680 */ 1681 return (0); 1682 } 1683 } 1684 1685 for (ifp = TAILQ_FIRST(&ifnet); ifp; ifp = TAILQ_NEXT(ifp, if_list)) 1686 { 1687 addrsofif = 0; 1688 for (ifa = ifp->if_addrlist.tqh_first; ifa; 1689 ifa = ifa->ifa_list.tqe_next) 1690 { 1691 if (ifa->ifa_addr->sa_family != AF_INET6) 1692 continue; 1693 ifa6 = (struct in6_ifaddr *)ifa; 1694 1695 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0 && 1696 IN6_ARE_ADDR_EQUAL(&subj_ip6->sin6_addr, 1697 &ifa6->ia_addr.sin6_addr)) 1698 iffound = 1; 1699 1700 /* 1701 * IPv4-mapped addresses can only be returned by a 1702 * Node Information proxy, since they represent 1703 * addresses of IPv4-only nodes, which perforce do 1704 * not implement this protocol. 1705 * [icmp-name-lookups-07, Section 5.4] 1706 * So we don't support NI_NODEADDR_FLAG_COMPAT in 1707 * this function at this moment. 1708 */ 1709 1710 /* What do we have to do about ::1? */ 1711 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1712 case IPV6_ADDR_SCOPE_LINKLOCAL: 1713 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0) 1714 continue; 1715 break; 1716 case IPV6_ADDR_SCOPE_SITELOCAL: 1717 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0) 1718 continue; 1719 break; 1720 case IPV6_ADDR_SCOPE_GLOBAL: 1721 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0) 1722 continue; 1723 break; 1724 default: 1725 continue; 1726 } 1727 1728 /* 1729 * check if anycast is okay. 1730 * XXX: just experimental. not in the spec. 1731 */ 1732 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 && 1733 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0) 1734 continue; /* we need only unicast addresses */ 1735 1736 addrsofif++; /* count the address */ 1737 } 1738 if (iffound) { 1739 *ifpp = ifp; 1740 return (addrsofif); 1741 } 1742 1743 addrs += addrsofif; 1744 } 1745 1746 return (addrs); 1747 } 1748 1749 static int 1750 ni6_store_addrs(ni6, nni6, ifp0, resid) 1751 struct icmp6_nodeinfo *ni6, *nni6; 1752 struct ifnet *ifp0; 1753 int resid; 1754 { 1755 struct ifnet *ifp = ifp0 ? ifp0 : TAILQ_FIRST(&ifnet); 1756 struct in6_ifaddr *ifa6; 1757 struct ifaddr *ifa; 1758 struct ifnet *ifp_dep = NULL; 1759 int copied = 0, allow_deprecated = 0; 1760 u_char *cp = (u_char *)(nni6 + 1); 1761 int niflags = ni6->ni_flags; 1762 u_int32_t ltime; 1763 1764 if (ifp0 == NULL && !(niflags & NI_NODEADDR_FLAG_ALL)) 1765 return (0); /* needless to copy */ 1766 1767 again: 1768 1769 for (; ifp; ifp = TAILQ_NEXT(ifp, if_list)) 1770 { 1771 for (ifa = ifp->if_addrlist.tqh_first; ifa; 1772 ifa = ifa->ifa_list.tqe_next) 1773 { 1774 if (ifa->ifa_addr->sa_family != AF_INET6) 1775 continue; 1776 ifa6 = (struct in6_ifaddr *)ifa; 1777 1778 if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) != 0 && 1779 allow_deprecated == 0) { 1780 /* 1781 * prefererred address should be put before 1782 * deprecated addresses. 1783 */ 1784 1785 /* record the interface for later search */ 1786 if (ifp_dep == NULL) 1787 ifp_dep = ifp; 1788 1789 continue; 1790 } 1791 else if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) == 0 && 1792 allow_deprecated != 0) 1793 continue; /* we now collect deprecated addrs */ 1794 1795 /* What do we have to do about ::1? */ 1796 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1797 case IPV6_ADDR_SCOPE_LINKLOCAL: 1798 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0) 1799 continue; 1800 break; 1801 case IPV6_ADDR_SCOPE_SITELOCAL: 1802 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0) 1803 continue; 1804 break; 1805 case IPV6_ADDR_SCOPE_GLOBAL: 1806 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0) 1807 continue; 1808 break; 1809 default: 1810 continue; 1811 } 1812 1813 /* 1814 * check if anycast is okay. 1815 * XXX: just experimental. not in the spec. 1816 */ 1817 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 && 1818 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0) 1819 continue; 1820 1821 /* now we can copy the address */ 1822 if (resid < sizeof(struct in6_addr) + 1823 sizeof(u_int32_t)) { 1824 /* 1825 * We give up much more copy. 1826 * Set the truncate flag and return. 1827 */ 1828 nni6->ni_flags |= 1829 NI_NODEADDR_FLAG_TRUNCATE; 1830 return (copied); 1831 } 1832 1833 /* 1834 * Set the TTL of the address. 1835 * The TTL value should be one of the following 1836 * according to the specification: 1837 * 1838 * 1. The remaining lifetime of a DHCP lease on the 1839 * address, or 1840 * 2. The remaining Valid Lifetime of a prefix from 1841 * which the address was derived through Stateless 1842 * Autoconfiguration. 1843 * 1844 * Note that we currently do not support stateful 1845 * address configuration by DHCPv6, so the former 1846 * case can't happen. 1847 * 1848 * TTL must be 2^31 > TTL >= 0. 1849 */ 1850 if (ifa6->ia6_lifetime.ia6t_expire == 0) 1851 ltime = ND6_INFINITE_LIFETIME; 1852 else { 1853 if (ifa6->ia6_lifetime.ia6t_expire > 1854 time.tv_sec) 1855 ltime = ifa6->ia6_lifetime.ia6t_expire - time.tv_sec; 1856 else 1857 ltime = 0; 1858 } 1859 if (ltime > 0x7fffffff) 1860 ltime = 0x7fffffff; 1861 ltime = htonl(ltime); 1862 1863 bcopy(<ime, cp, sizeof(u_int32_t)); 1864 cp += sizeof(u_int32_t); 1865 1866 /* copy the address itself */ 1867 bcopy(&ifa6->ia_addr.sin6_addr, cp, 1868 sizeof(struct in6_addr)); 1869 /* XXX: KAME link-local hack; remove ifindex */ 1870 if (IN6_IS_ADDR_LINKLOCAL(&ifa6->ia_addr.sin6_addr)) 1871 ((struct in6_addr *)cp)->s6_addr16[1] = 0; 1872 cp += sizeof(struct in6_addr); 1873 1874 resid -= (sizeof(struct in6_addr) + sizeof(u_int32_t)); 1875 copied += (sizeof(struct in6_addr) + 1876 sizeof(u_int32_t)); 1877 } 1878 if (ifp0) /* we need search only on the specified IF */ 1879 break; 1880 } 1881 1882 if (allow_deprecated == 0 && ifp_dep != NULL) { 1883 ifp = ifp_dep; 1884 allow_deprecated = 1; 1885 1886 goto again; 1887 } 1888 1889 return (copied); 1890 } 1891 1892 /* 1893 * XXX almost dup'ed code with rip6_input. 1894 */ 1895 static int 1896 icmp6_rip6_input(mp, off) 1897 struct mbuf **mp; 1898 int off; 1899 { 1900 struct mbuf *m = *mp; 1901 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1902 struct in6pcb *in6p; 1903 struct in6pcb *last = NULL; 1904 struct sockaddr_in6 rip6src; 1905 struct icmp6_hdr *icmp6; 1906 struct mbuf *opts = NULL; 1907 1908 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 1909 if (icmp6 == NULL) { 1910 /* m is already reclaimed */ 1911 return IPPROTO_DONE; 1912 } 1913 1914 bzero(&rip6src, sizeof(rip6src)); 1915 rip6src.sin6_len = sizeof(struct sockaddr_in6); 1916 rip6src.sin6_family = AF_INET6; 1917 /* KAME hack: recover scopeid */ 1918 (void)in6_recoverscope(&rip6src, &ip6->ip6_src, m->m_pkthdr.rcvif); 1919 1920 for (in6p = rawin6pcb.in6p_next; 1921 in6p != &rawin6pcb; in6p = in6p->in6p_next) 1922 { 1923 if (in6p->in6p_ip6_nxt != IPPROTO_ICMPV6) 1924 continue; 1925 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr) && 1926 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr, &ip6->ip6_dst)) 1927 continue; 1928 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr) && 1929 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr, &ip6->ip6_src)) 1930 continue; 1931 if (in6p->in6p_icmp6filt 1932 && ICMP6_FILTER_WILLBLOCK(icmp6->icmp6_type, 1933 in6p->in6p_icmp6filt)) 1934 continue; 1935 if (last) { 1936 struct mbuf *n; 1937 if ((n = m_copy(m, 0, (int)M_COPYALL)) != NULL) { 1938 if (last->in6p_flags & IN6P_CONTROLOPTS) 1939 ip6_savecontrol(last, &opts, ip6, n); 1940 /* strip intermediate headers */ 1941 m_adj(n, off); 1942 if (sbappendaddr(&last->in6p_socket->so_rcv, 1943 (struct sockaddr *)&rip6src, 1944 n, opts) == 0) { 1945 /* should notify about lost packet */ 1946 m_freem(n); 1947 if (opts) 1948 m_freem(opts); 1949 } else 1950 sorwakeup(last->in6p_socket); 1951 opts = NULL; 1952 } 1953 } 1954 last = in6p; 1955 } 1956 if (last) { 1957 if (last->in6p_flags & IN6P_CONTROLOPTS) 1958 ip6_savecontrol(last, &opts, ip6, m); 1959 /* strip intermediate headers */ 1960 m_adj(m, off); 1961 if (sbappendaddr(&last->in6p_socket->so_rcv, 1962 (struct sockaddr *)&rip6src, m, opts) == 0) { 1963 m_freem(m); 1964 if (opts) 1965 m_freem(opts); 1966 } else 1967 sorwakeup(last->in6p_socket); 1968 } else { 1969 m_freem(m); 1970 ip6stat.ip6s_delivered--; 1971 } 1972 return IPPROTO_DONE; 1973 } 1974 1975 /* 1976 * Reflect the ip6 packet back to the source. 1977 * OFF points to the icmp6 header, counted from the top of the mbuf. 1978 * 1979 * Note: RFC 1885 required that an echo reply should be truncated if it 1980 * did not fit in with (return) path MTU, and KAME code supported the 1981 * behavior. However, as a clarification after the RFC, this limitation 1982 * was removed in a revised version of the spec, RFC 2463. We had kept the 1983 * old behavior, with a (non-default) ifdef block, while the new version of 1984 * the spec was an internet-draft status, and even after the new RFC was 1985 * published. But it would rather make sense to clean the obsoleted part 1986 * up, and to make the code simpler at this stage. 1987 */ 1988 void 1989 icmp6_reflect(m, off) 1990 struct mbuf *m; 1991 size_t off; 1992 { 1993 struct ip6_hdr *ip6; 1994 struct icmp6_hdr *icmp6; 1995 struct in6_ifaddr *ia; 1996 struct in6_addr t, *src = 0; 1997 int plen; 1998 int type, code; 1999 struct ifnet *outif = NULL; 2000 struct sockaddr_in6 sa6_src, sa6_dst; 2001 2002 /* too short to reflect */ 2003 if (off < sizeof(struct ip6_hdr)) { 2004 nd6log((LOG_DEBUG, 2005 "sanity fail: off=%lx, sizeof(ip6)=%lx in %s:%d\n", 2006 (u_long)off, (u_long)sizeof(struct ip6_hdr), 2007 __FILE__, __LINE__)); 2008 goto bad; 2009 } 2010 2011 /* 2012 * If there are extra headers between IPv6 and ICMPv6, strip 2013 * off that header first. 2014 */ 2015 #ifdef DIAGNOSTIC 2016 if (sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) > MHLEN) 2017 panic("assumption failed in icmp6_reflect"); 2018 #endif 2019 if (off > sizeof(struct ip6_hdr)) { 2020 size_t l; 2021 struct ip6_hdr nip6; 2022 2023 l = off - sizeof(struct ip6_hdr); 2024 m_copydata(m, 0, sizeof(nip6), (caddr_t)&nip6); 2025 m_adj(m, l); 2026 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 2027 if (m->m_len < l) { 2028 if ((m = m_pullup(m, l)) == NULL) 2029 return; 2030 } 2031 bcopy((caddr_t)&nip6, mtod(m, caddr_t), sizeof(nip6)); 2032 } else /* off == sizeof(struct ip6_hdr) */ { 2033 size_t l; 2034 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 2035 if (m->m_len < l) { 2036 if ((m = m_pullup(m, l)) == NULL) 2037 return; 2038 } 2039 } 2040 plen = m->m_pkthdr.len - sizeof(struct ip6_hdr); 2041 ip6 = mtod(m, struct ip6_hdr *); 2042 ip6->ip6_nxt = IPPROTO_ICMPV6; 2043 icmp6 = (struct icmp6_hdr *)(ip6 + 1); 2044 type = icmp6->icmp6_type; /* keep type for statistics */ 2045 code = icmp6->icmp6_code; /* ditto. */ 2046 2047 t = ip6->ip6_dst; 2048 /* 2049 * ip6_input() drops a packet if its src is multicast. 2050 * So, the src is never multicast. 2051 */ 2052 ip6->ip6_dst = ip6->ip6_src; 2053 2054 /* 2055 * XXX: make sure to embed scope zone information, using 2056 * already embedded IDs or the received interface (if any). 2057 * Note that rcvif may be NULL. 2058 * TODO: scoped routing case (XXX). 2059 */ 2060 bzero(&sa6_src, sizeof(sa6_src)); 2061 sa6_src.sin6_family = AF_INET6; 2062 sa6_src.sin6_len = sizeof(sa6_src); 2063 sa6_src.sin6_addr = ip6->ip6_dst; 2064 in6_recoverscope(&sa6_src, &ip6->ip6_dst, m->m_pkthdr.rcvif); 2065 in6_embedscope(&sa6_src.sin6_addr, &sa6_src, NULL, NULL); 2066 ip6->ip6_dst = sa6_src.sin6_addr; 2067 2068 bzero(&sa6_dst, sizeof(sa6_dst)); 2069 sa6_dst.sin6_family = AF_INET6; 2070 sa6_dst.sin6_len = sizeof(sa6_dst); 2071 sa6_dst.sin6_addr = t; 2072 in6_recoverscope(&sa6_dst, &t, m->m_pkthdr.rcvif); 2073 in6_embedscope(&t, &sa6_dst, NULL, NULL); 2074 2075 /* 2076 * If the incoming packet was addressed directly to us (i.e. unicast), 2077 * use dst as the src for the reply. 2078 * The IN6_IFF_NOTREADY case would be VERY rare, but is possible 2079 * (for example) when we encounter an error while forwarding procedure 2080 * destined to a duplicated address of ours. 2081 */ 2082 for (ia = in6_ifaddr; ia; ia = ia->ia_next) 2083 if (IN6_ARE_ADDR_EQUAL(&t, &ia->ia_addr.sin6_addr) && 2084 (ia->ia6_flags & (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY)) == 0) { 2085 src = &t; 2086 break; 2087 } 2088 if (ia == NULL && IN6_IS_ADDR_LINKLOCAL(&t) && (m->m_flags & M_LOOP)) { 2089 /* 2090 * This is the case if the dst is our link-local address 2091 * and the sender is also ourselves. 2092 */ 2093 src = &t; 2094 } 2095 2096 if (src == 0) { 2097 int e; 2098 struct route_in6 ro; 2099 2100 /* 2101 * This case matches to multicasts, our anycast, or unicasts 2102 * that we do not own. Select a source address based on the 2103 * source address of the erroneous packet. 2104 */ 2105 bzero(&ro, sizeof(ro)); 2106 src = in6_selectsrc(&sa6_src, NULL, NULL, &ro, NULL, &e); 2107 if (ro.ro_rt) { /* XXX: see comments in icmp6_mtudisc_update */ 2108 RTFREE(ro.ro_rt); /* XXX: we could use this */ 2109 } 2110 if (src == NULL) { 2111 nd6log((LOG_DEBUG, 2112 "icmp6_reflect: source can't be determined: " 2113 "dst=%s, error=%d\n", 2114 ip6_sprintf(&sa6_src.sin6_addr), e)); 2115 goto bad; 2116 } 2117 } 2118 2119 ip6->ip6_src = *src; 2120 2121 ip6->ip6_flow = 0; 2122 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2123 ip6->ip6_vfc |= IPV6_VERSION; 2124 ip6->ip6_nxt = IPPROTO_ICMPV6; 2125 if (m->m_pkthdr.rcvif) { 2126 /* XXX: This may not be the outgoing interface */ 2127 ip6->ip6_hlim = ND_IFINFO(m->m_pkthdr.rcvif)->chlim; 2128 } else 2129 ip6->ip6_hlim = ip6_defhlim; 2130 2131 icmp6->icmp6_cksum = 0; 2132 icmp6->icmp6_cksum = in6_cksum(m, IPPROTO_ICMPV6, 2133 sizeof(struct ip6_hdr), plen); 2134 2135 /* 2136 * XXX option handling 2137 */ 2138 2139 m->m_flags &= ~(M_BCAST|M_MCAST); 2140 #ifdef IPSEC 2141 /* Don't lookup socket */ 2142 (void)ipsec_setsocket(m, NULL); 2143 #endif /* IPSEC */ 2144 2145 /* 2146 * To avoid a "too big" situation at an intermediate router 2147 * and the path MTU discovery process, specify the IPV6_MINMTU flag. 2148 * Note that only echo and node information replies are affected, 2149 * since the length of ICMP6 errors is limited to the minimum MTU. 2150 */ 2151 if (ip6_output(m, NULL, NULL, IPV6_MINMTU, NULL, &outif) != 0 && outif) 2152 icmp6_ifstat_inc(outif, ifs6_out_error); 2153 2154 if (outif) 2155 icmp6_ifoutstat_inc(outif, type, code); 2156 2157 return; 2158 2159 bad: 2160 m_freem(m); 2161 return; 2162 } 2163 2164 void 2165 icmp6_fasttimo() 2166 { 2167 2168 mld6_fasttimeo(); 2169 } 2170 2171 static const char * 2172 icmp6_redirect_diag(src6, dst6, tgt6) 2173 struct in6_addr *src6; 2174 struct in6_addr *dst6; 2175 struct in6_addr *tgt6; 2176 { 2177 static char buf[1024]; 2178 snprintf(buf, sizeof(buf), "(src=%s dst=%s tgt=%s)", 2179 ip6_sprintf(src6), ip6_sprintf(dst6), ip6_sprintf(tgt6)); 2180 return buf; 2181 } 2182 2183 void 2184 icmp6_redirect_input(m, off) 2185 struct mbuf *m; 2186 int off; 2187 { 2188 struct ifnet *ifp = m->m_pkthdr.rcvif; 2189 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 2190 struct nd_redirect *nd_rd; 2191 int icmp6len = ntohs(ip6->ip6_plen); 2192 char *lladdr = NULL; 2193 int lladdrlen = 0; 2194 u_char *redirhdr = NULL; 2195 int redirhdrlen = 0; 2196 struct rtentry *rt = NULL; 2197 int is_router; 2198 int is_onlink; 2199 struct in6_addr src6 = ip6->ip6_src; 2200 struct in6_addr redtgt6; 2201 struct in6_addr reddst6; 2202 union nd_opts ndopts; 2203 2204 if (!ifp) 2205 return; 2206 2207 /* XXX if we are router, we don't update route by icmp6 redirect */ 2208 if (ip6_forwarding) 2209 goto freeit; 2210 if (!icmp6_rediraccept) 2211 goto freeit; 2212 2213 IP6_EXTHDR_GET(nd_rd, struct nd_redirect *, m, off, icmp6len); 2214 if (nd_rd == NULL) { 2215 icmp6stat.icp6s_tooshort++; 2216 return; 2217 } 2218 redtgt6 = nd_rd->nd_rd_target; 2219 reddst6 = nd_rd->nd_rd_dst; 2220 2221 if (IN6_IS_ADDR_LINKLOCAL(&redtgt6)) 2222 redtgt6.s6_addr16[1] = htons(ifp->if_index); 2223 if (IN6_IS_ADDR_LINKLOCAL(&reddst6)) 2224 reddst6.s6_addr16[1] = htons(ifp->if_index); 2225 2226 /* validation */ 2227 if (!IN6_IS_ADDR_LINKLOCAL(&src6)) { 2228 nd6log((LOG_ERR, 2229 "ICMP6 redirect sent from %s rejected; " 2230 "must be from linklocal\n", ip6_sprintf(&src6))); 2231 goto bad; 2232 } 2233 if (ip6->ip6_hlim != 255) { 2234 nd6log((LOG_ERR, 2235 "ICMP6 redirect sent from %s rejected; " 2236 "hlim=%d (must be 255)\n", 2237 ip6_sprintf(&src6), ip6->ip6_hlim)); 2238 goto bad; 2239 } 2240 { 2241 /* ip6->ip6_src must be equal to gw for icmp6->icmp6_reddst */ 2242 struct sockaddr_in6 sin6; 2243 struct in6_addr *gw6; 2244 2245 bzero(&sin6, sizeof(sin6)); 2246 sin6.sin6_family = AF_INET6; 2247 sin6.sin6_len = sizeof(struct sockaddr_in6); 2248 bcopy(&reddst6, &sin6.sin6_addr, sizeof(reddst6)); 2249 rt = rtalloc1((struct sockaddr *)&sin6, 0); 2250 if (rt) { 2251 if (rt->rt_gateway == NULL || 2252 rt->rt_gateway->sa_family != AF_INET6) { 2253 nd6log((LOG_ERR, 2254 "ICMP6 redirect rejected; no route " 2255 "with inet6 gateway found for redirect dst: %s\n", 2256 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2257 RTFREE(rt); 2258 goto bad; 2259 } 2260 2261 gw6 = &(((struct sockaddr_in6 *)rt->rt_gateway)->sin6_addr); 2262 if (bcmp(&src6, gw6, sizeof(struct in6_addr)) != 0) { 2263 nd6log((LOG_ERR, 2264 "ICMP6 redirect rejected; " 2265 "not equal to gw-for-src=%s (must be same): " 2266 "%s\n", 2267 ip6_sprintf(gw6), 2268 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2269 RTFREE(rt); 2270 goto bad; 2271 } 2272 } else { 2273 nd6log((LOG_ERR, 2274 "ICMP6 redirect rejected; " 2275 "no route found for redirect dst: %s\n", 2276 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2277 goto bad; 2278 } 2279 RTFREE(rt); 2280 rt = NULL; 2281 } 2282 if (IN6_IS_ADDR_MULTICAST(&reddst6)) { 2283 nd6log((LOG_ERR, 2284 "ICMP6 redirect rejected; " 2285 "redirect dst must be unicast: %s\n", 2286 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2287 goto bad; 2288 } 2289 2290 is_router = is_onlink = 0; 2291 if (IN6_IS_ADDR_LINKLOCAL(&redtgt6)) 2292 is_router = 1; /* router case */ 2293 if (bcmp(&redtgt6, &reddst6, sizeof(redtgt6)) == 0) 2294 is_onlink = 1; /* on-link destination case */ 2295 if (!is_router && !is_onlink) { 2296 nd6log((LOG_ERR, 2297 "ICMP6 redirect rejected; " 2298 "neither router case nor onlink case: %s\n", 2299 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2300 goto bad; 2301 } 2302 /* validation passed */ 2303 2304 icmp6len -= sizeof(*nd_rd); 2305 nd6_option_init(nd_rd + 1, icmp6len, &ndopts); 2306 if (nd6_options(&ndopts) < 0) { 2307 nd6log((LOG_INFO, "icmp6_redirect_input: " 2308 "invalid ND option, rejected: %s\n", 2309 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2310 /* nd6_options have incremented stats */ 2311 goto freeit; 2312 } 2313 2314 if (ndopts.nd_opts_tgt_lladdr) { 2315 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 2316 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 2317 } 2318 2319 if (ndopts.nd_opts_rh) { 2320 redirhdrlen = ndopts.nd_opts_rh->nd_opt_rh_len; 2321 redirhdr = (u_char *)(ndopts.nd_opts_rh + 1); /* xxx */ 2322 } 2323 2324 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 2325 nd6log((LOG_INFO, 2326 "icmp6_redirect_input: lladdrlen mismatch for %s " 2327 "(if %d, icmp6 packet %d): %s\n", 2328 ip6_sprintf(&redtgt6), ifp->if_addrlen, lladdrlen - 2, 2329 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2330 goto bad; 2331 } 2332 2333 /* RFC 2461 8.3 */ 2334 nd6_cache_lladdr(ifp, &redtgt6, lladdr, lladdrlen, ND_REDIRECT, 2335 is_onlink ? ND_REDIRECT_ONLINK : ND_REDIRECT_ROUTER); 2336 2337 if (!is_onlink) { /* better router case. perform rtredirect. */ 2338 /* perform rtredirect */ 2339 struct sockaddr_in6 sdst; 2340 struct sockaddr_in6 sgw; 2341 struct sockaddr_in6 ssrc; 2342 unsigned long rtcount; 2343 struct rtentry *newrt = NULL; 2344 2345 /* 2346 * do not install redirect route, if the number of entries 2347 * is too much (> hiwat). note that, the node (= host) will 2348 * work just fine even if we do not install redirect route 2349 * (there will be additional hops, though). 2350 */ 2351 rtcount = rt_timer_count(icmp6_redirect_timeout_q); 2352 if (0 <= icmp6_redirect_hiwat && rtcount > icmp6_redirect_hiwat) 2353 return; 2354 else if (0 <= icmp6_redirect_lowat && 2355 rtcount > icmp6_redirect_lowat) { 2356 /* 2357 * XXX nuke a victim, install the new one. 2358 */ 2359 } 2360 2361 bzero(&sdst, sizeof(sdst)); 2362 bzero(&sgw, sizeof(sgw)); 2363 bzero(&ssrc, sizeof(ssrc)); 2364 sdst.sin6_family = sgw.sin6_family = ssrc.sin6_family = AF_INET6; 2365 sdst.sin6_len = sgw.sin6_len = ssrc.sin6_len = 2366 sizeof(struct sockaddr_in6); 2367 bcopy(&redtgt6, &sgw.sin6_addr, sizeof(struct in6_addr)); 2368 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2369 bcopy(&src6, &ssrc.sin6_addr, sizeof(struct in6_addr)); 2370 rtredirect((struct sockaddr *)&sdst, (struct sockaddr *)&sgw, 2371 (struct sockaddr *)NULL, RTF_GATEWAY | RTF_HOST, 2372 (struct sockaddr *)&ssrc, 2373 &newrt); 2374 2375 if (newrt) { 2376 (void)rt_timer_add(newrt, icmp6_redirect_timeout, 2377 icmp6_redirect_timeout_q); 2378 rtfree(newrt); 2379 } 2380 } 2381 /* finally update cached route in each socket via pfctlinput */ 2382 { 2383 struct sockaddr_in6 sdst; 2384 2385 bzero(&sdst, sizeof(sdst)); 2386 sdst.sin6_family = AF_INET6; 2387 sdst.sin6_len = sizeof(struct sockaddr_in6); 2388 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2389 pfctlinput(PRC_REDIRECT_HOST, (struct sockaddr *)&sdst); 2390 #ifdef IPSEC 2391 key_sa_routechange((struct sockaddr *)&sdst); 2392 #endif 2393 } 2394 2395 freeit: 2396 m_freem(m); 2397 return; 2398 2399 bad: 2400 icmp6stat.icp6s_badredirect++; 2401 m_freem(m); 2402 } 2403 2404 void 2405 icmp6_redirect_output(m0, rt) 2406 struct mbuf *m0; 2407 struct rtentry *rt; 2408 { 2409 struct ifnet *ifp; /* my outgoing interface */ 2410 struct in6_addr *ifp_ll6; 2411 struct in6_addr *nexthop; 2412 struct ip6_hdr *sip6; /* m0 as struct ip6_hdr */ 2413 struct mbuf *m = NULL; /* newly allocated one */ 2414 struct ip6_hdr *ip6; /* m as struct ip6_hdr */ 2415 struct nd_redirect *nd_rd; 2416 size_t maxlen; 2417 u_char *p; 2418 struct sockaddr_in6 src_sa; 2419 2420 icmp6_errcount(&icmp6stat.icp6s_outerrhist, ND_REDIRECT, 0); 2421 2422 /* if we are not router, we don't send icmp6 redirect */ 2423 if (!ip6_forwarding) 2424 goto fail; 2425 2426 /* sanity check */ 2427 if (!m0 || !rt || !(rt->rt_flags & RTF_UP) || !(ifp = rt->rt_ifp)) 2428 goto fail; 2429 2430 /* 2431 * Address check: 2432 * the source address must identify a neighbor, and 2433 * the destination address must not be a multicast address 2434 * [RFC 2461, sec 8.2] 2435 */ 2436 sip6 = mtod(m0, struct ip6_hdr *); 2437 bzero(&src_sa, sizeof(src_sa)); 2438 src_sa.sin6_family = AF_INET6; 2439 src_sa.sin6_len = sizeof(src_sa); 2440 src_sa.sin6_addr = sip6->ip6_src; 2441 /* we don't currently use sin6_scope_id, but eventually use it */ 2442 src_sa.sin6_scope_id = in6_addr2scopeid(ifp, &sip6->ip6_src); 2443 if (nd6_is_addr_neighbor(&src_sa, ifp) == 0) 2444 goto fail; 2445 if (IN6_IS_ADDR_MULTICAST(&sip6->ip6_dst)) 2446 goto fail; /* what should we do here? */ 2447 2448 /* rate limit */ 2449 if (icmp6_ratelimit(&sip6->ip6_src, ND_REDIRECT, 0)) 2450 goto fail; 2451 2452 /* 2453 * Since we are going to append up to 1280 bytes (= IPV6_MMTU), 2454 * we almost always ask for an mbuf cluster for simplicity. 2455 * (MHLEN < IPV6_MMTU is almost always true) 2456 */ 2457 #if IPV6_MMTU >= MCLBYTES 2458 # error assumption failed about IPV6_MMTU and MCLBYTES 2459 #endif 2460 MGETHDR(m, M_DONTWAIT, MT_HEADER); 2461 if (m && IPV6_MMTU >= MHLEN) 2462 MCLGET(m, M_DONTWAIT); 2463 if (!m) 2464 goto fail; 2465 m->m_pkthdr.rcvif = NULL; 2466 m->m_len = 0; 2467 maxlen = M_TRAILINGSPACE(m); 2468 maxlen = min(IPV6_MMTU, maxlen); 2469 /* just for safety */ 2470 if (maxlen < sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) + 2471 ((sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7)) { 2472 goto fail; 2473 } 2474 2475 { 2476 /* get ip6 linklocal address for ifp(my outgoing interface). */ 2477 struct in6_ifaddr *ia; 2478 if ((ia = in6ifa_ifpforlinklocal(ifp, 2479 IN6_IFF_NOTREADY| 2480 IN6_IFF_ANYCAST)) == NULL) 2481 goto fail; 2482 ifp_ll6 = &ia->ia_addr.sin6_addr; 2483 } 2484 2485 /* get ip6 linklocal address for the router. */ 2486 if (rt->rt_gateway && (rt->rt_flags & RTF_GATEWAY)) { 2487 struct sockaddr_in6 *sin6; 2488 sin6 = (struct sockaddr_in6 *)rt->rt_gateway; 2489 nexthop = &sin6->sin6_addr; 2490 if (!IN6_IS_ADDR_LINKLOCAL(nexthop)) 2491 nexthop = NULL; 2492 } else 2493 nexthop = NULL; 2494 2495 /* ip6 */ 2496 ip6 = mtod(m, struct ip6_hdr *); 2497 ip6->ip6_flow = 0; 2498 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2499 ip6->ip6_vfc |= IPV6_VERSION; 2500 /* ip6->ip6_plen will be set later */ 2501 ip6->ip6_nxt = IPPROTO_ICMPV6; 2502 ip6->ip6_hlim = 255; 2503 /* ip6->ip6_src must be linklocal addr for my outgoing if. */ 2504 bcopy(ifp_ll6, &ip6->ip6_src, sizeof(struct in6_addr)); 2505 bcopy(&sip6->ip6_src, &ip6->ip6_dst, sizeof(struct in6_addr)); 2506 2507 /* ND Redirect */ 2508 nd_rd = (struct nd_redirect *)(ip6 + 1); 2509 nd_rd->nd_rd_type = ND_REDIRECT; 2510 nd_rd->nd_rd_code = 0; 2511 nd_rd->nd_rd_reserved = 0; 2512 if (rt->rt_flags & RTF_GATEWAY) { 2513 /* 2514 * nd_rd->nd_rd_target must be a link-local address in 2515 * better router cases. 2516 */ 2517 if (!nexthop) 2518 goto fail; 2519 bcopy(nexthop, &nd_rd->nd_rd_target, 2520 sizeof(nd_rd->nd_rd_target)); 2521 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2522 sizeof(nd_rd->nd_rd_dst)); 2523 } else { 2524 /* make sure redtgt == reddst */ 2525 nexthop = &sip6->ip6_dst; 2526 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_target, 2527 sizeof(nd_rd->nd_rd_target)); 2528 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2529 sizeof(nd_rd->nd_rd_dst)); 2530 } 2531 2532 p = (u_char *)(nd_rd + 1); 2533 2534 { 2535 /* target lladdr option */ 2536 struct rtentry *rt_nexthop = NULL; 2537 int len; 2538 struct sockaddr_dl *sdl; 2539 struct nd_opt_hdr *nd_opt; 2540 char *lladdr; 2541 2542 rt_nexthop = nd6_lookup(nexthop, 0, ifp); 2543 if (!rt_nexthop) 2544 goto nolladdropt; 2545 len = sizeof(*nd_opt) + ifp->if_addrlen; 2546 len = (len + 7) & ~7; /* round by 8 */ 2547 /* safety check */ 2548 if (len + (p - (u_char *)ip6) > maxlen) 2549 goto nolladdropt; 2550 if (!(rt_nexthop->rt_flags & RTF_GATEWAY) && 2551 (rt_nexthop->rt_flags & RTF_LLINFO) && 2552 (rt_nexthop->rt_gateway->sa_family == AF_LINK) && 2553 (sdl = (struct sockaddr_dl *)rt_nexthop->rt_gateway) && 2554 sdl->sdl_alen) { 2555 nd_opt = (struct nd_opt_hdr *)p; 2556 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 2557 nd_opt->nd_opt_len = len >> 3; 2558 lladdr = (char *)(nd_opt + 1); 2559 bcopy(LLADDR(sdl), lladdr, ifp->if_addrlen); 2560 p += len; 2561 } 2562 } 2563 nolladdropt:; 2564 2565 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2566 2567 /* just to be safe */ 2568 if (m0->m_flags & M_DECRYPTED) 2569 goto noredhdropt; 2570 if (p - (u_char *)ip6 > maxlen) 2571 goto noredhdropt; 2572 2573 { 2574 /* redirected header option */ 2575 int len; 2576 struct nd_opt_rd_hdr *nd_opt_rh; 2577 2578 /* 2579 * compute the maximum size for icmp6 redirect header option. 2580 * XXX room for auth header? 2581 */ 2582 len = maxlen - (p - (u_char *)ip6); 2583 len &= ~7; 2584 2585 /* 2586 * Redirected header option spec (RFC2461 4.6.3) talks nothing 2587 * about padding/truncate rule for the original IP packet. 2588 * From the discussion on IPv6imp in Feb 1999, 2589 * the consensus was: 2590 * - "attach as much as possible" is the goal 2591 * - pad if not aligned (original size can be guessed by 2592 * original ip6 header) 2593 * Following code adds the padding if it is simple enough, 2594 * and truncates if not. 2595 */ 2596 if (len - sizeof(*nd_opt_rh) < m0->m_pkthdr.len) { 2597 /* not enough room, truncate */ 2598 m_adj(m0, (len - sizeof(*nd_opt_rh)) - 2599 m0->m_pkthdr.len); 2600 } else { 2601 /* 2602 * enough room, truncate if not aligned. 2603 * we don't pad here for simplicity. 2604 */ 2605 size_t extra; 2606 2607 extra = m0->m_pkthdr.len % 8; 2608 if (extra) { 2609 /* truncate */ 2610 m_adj(m0, -extra); 2611 } 2612 len = m0->m_pkthdr.len + sizeof(*nd_opt_rh); 2613 } 2614 2615 nd_opt_rh = (struct nd_opt_rd_hdr *)p; 2616 bzero(nd_opt_rh, sizeof(*nd_opt_rh)); 2617 nd_opt_rh->nd_opt_rh_type = ND_OPT_REDIRECTED_HEADER; 2618 nd_opt_rh->nd_opt_rh_len = len >> 3; 2619 p += sizeof(*nd_opt_rh); 2620 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2621 2622 /* connect m0 to m */ 2623 m_cat(m, m0); 2624 m->m_pkthdr.len += m0->m_pkthdr.len; 2625 m0 = NULL; 2626 } 2627 noredhdropt: 2628 if (m0) { 2629 m_freem(m0); 2630 m0 = NULL; 2631 } 2632 2633 if (IN6_IS_ADDR_LINKLOCAL(&sip6->ip6_src)) 2634 sip6->ip6_src.s6_addr16[1] = 0; 2635 if (IN6_IS_ADDR_LINKLOCAL(&sip6->ip6_dst)) 2636 sip6->ip6_dst.s6_addr16[1] = 0; 2637 #if 0 2638 if (IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_src)) 2639 ip6->ip6_src.s6_addr16[1] = 0; 2640 if (IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_dst)) 2641 ip6->ip6_dst.s6_addr16[1] = 0; 2642 #endif 2643 if (IN6_IS_ADDR_LINKLOCAL(&nd_rd->nd_rd_target)) 2644 nd_rd->nd_rd_target.s6_addr16[1] = 0; 2645 if (IN6_IS_ADDR_LINKLOCAL(&nd_rd->nd_rd_dst)) 2646 nd_rd->nd_rd_dst.s6_addr16[1] = 0; 2647 2648 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr)); 2649 2650 nd_rd->nd_rd_cksum = 0; 2651 nd_rd->nd_rd_cksum 2652 = in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), ntohs(ip6->ip6_plen)); 2653 2654 /* send the packet to outside... */ 2655 #ifdef IPSEC 2656 /* Don't lookup socket */ 2657 (void)ipsec_setsocket(m, NULL); 2658 #endif /* IPSEC */ 2659 if (ip6_output(m, NULL, NULL, 0, NULL, NULL) != 0) 2660 icmp6_ifstat_inc(ifp, ifs6_out_error); 2661 2662 icmp6_ifstat_inc(ifp, ifs6_out_msg); 2663 icmp6_ifstat_inc(ifp, ifs6_out_redirect); 2664 icmp6stat.icp6s_outhist[ND_REDIRECT]++; 2665 2666 return; 2667 2668 fail: 2669 if (m) 2670 m_freem(m); 2671 if (m0) 2672 m_freem(m0); 2673 } 2674 2675 /* 2676 * ICMPv6 socket option processing. 2677 */ 2678 int 2679 icmp6_ctloutput(op, so, level, optname, mp) 2680 int op; 2681 struct socket *so; 2682 int level, optname; 2683 struct mbuf **mp; 2684 { 2685 int error = 0; 2686 int optlen; 2687 struct in6pcb *in6p = sotoin6pcb(so); 2688 struct mbuf *m = *mp; 2689 2690 optlen = m ? m->m_len : 0; 2691 2692 if (level != IPPROTO_ICMPV6) { 2693 if (op == PRCO_SETOPT && m) 2694 (void)m_free(m); 2695 return EINVAL; 2696 } 2697 2698 switch (op) { 2699 case PRCO_SETOPT: 2700 switch (optname) { 2701 case ICMP6_FILTER: 2702 { 2703 struct icmp6_filter *p; 2704 2705 if (optlen != sizeof(*p)) { 2706 error = EMSGSIZE; 2707 break; 2708 } 2709 p = mtod(m, struct icmp6_filter *); 2710 if (!p || !in6p->in6p_icmp6filt) { 2711 error = EINVAL; 2712 break; 2713 } 2714 bcopy(p, in6p->in6p_icmp6filt, 2715 sizeof(struct icmp6_filter)); 2716 error = 0; 2717 break; 2718 } 2719 2720 default: 2721 error = ENOPROTOOPT; 2722 break; 2723 } 2724 if (m) 2725 (void)m_freem(m); 2726 break; 2727 2728 case PRCO_GETOPT: 2729 switch (optname) { 2730 case ICMP6_FILTER: 2731 { 2732 struct icmp6_filter *p; 2733 2734 if (!in6p->in6p_icmp6filt) { 2735 error = EINVAL; 2736 break; 2737 } 2738 *mp = m = m_get(M_WAIT, MT_SOOPTS); 2739 m->m_len = sizeof(struct icmp6_filter); 2740 p = mtod(m, struct icmp6_filter *); 2741 bcopy(in6p->in6p_icmp6filt, p, 2742 sizeof(struct icmp6_filter)); 2743 error = 0; 2744 break; 2745 } 2746 2747 default: 2748 error = ENOPROTOOPT; 2749 break; 2750 } 2751 break; 2752 } 2753 2754 return (error); 2755 } 2756 2757 /* 2758 * Perform rate limit check. 2759 * Returns 0 if it is okay to send the icmp6 packet. 2760 * Returns 1 if the router SHOULD NOT send this icmp6 packet due to rate 2761 * limitation. 2762 * 2763 * XXX per-destination/type check necessary? 2764 */ 2765 static int 2766 icmp6_ratelimit(dst, type, code) 2767 const struct in6_addr *dst; /* not used at this moment */ 2768 const int type; /* not used at this moment */ 2769 const int code; /* not used at this moment */ 2770 { 2771 int ret; 2772 2773 ret = 0; /* okay to send */ 2774 2775 /* PPS limit */ 2776 if (!ppsratecheck(&icmp6errppslim_last, &icmp6errpps_count, 2777 icmp6errppslim)) { 2778 /* The packet is subject to rate limit */ 2779 ret++; 2780 } 2781 2782 return ret; 2783 } 2784 2785 static struct rtentry * 2786 icmp6_mtudisc_clone(dst) 2787 struct sockaddr *dst; 2788 { 2789 struct rtentry *rt; 2790 int error; 2791 2792 rt = rtalloc1(dst, 1); 2793 if (rt == 0) 2794 return NULL; 2795 2796 /* If we didn't get a host route, allocate one */ 2797 if ((rt->rt_flags & RTF_HOST) == 0) { 2798 struct rtentry *nrt; 2799 2800 error = rtrequest((int) RTM_ADD, dst, 2801 (struct sockaddr *) rt->rt_gateway, 2802 (struct sockaddr *) 0, 2803 RTF_GATEWAY | RTF_HOST | RTF_DYNAMIC, &nrt); 2804 if (error) { 2805 rtfree(rt); 2806 return NULL; 2807 } 2808 nrt->rt_rmx = rt->rt_rmx; 2809 rtfree(rt); 2810 rt = nrt; 2811 } 2812 error = rt_timer_add(rt, icmp6_mtudisc_timeout, 2813 icmp6_mtudisc_timeout_q); 2814 if (error) { 2815 rtfree(rt); 2816 return NULL; 2817 } 2818 2819 return rt; /* caller need to call rtfree() */ 2820 } 2821 2822 static void 2823 icmp6_mtudisc_timeout(rt, r) 2824 struct rtentry *rt; 2825 struct rttimer *r; 2826 { 2827 if (rt == NULL) 2828 panic("icmp6_mtudisc_timeout: bad route to timeout"); 2829 if ((rt->rt_flags & (RTF_DYNAMIC | RTF_HOST)) == 2830 (RTF_DYNAMIC | RTF_HOST)) { 2831 rtrequest((int) RTM_DELETE, (struct sockaddr *)rt_key(rt), 2832 rt->rt_gateway, rt_mask(rt), rt->rt_flags, 0); 2833 } else { 2834 if (!(rt->rt_rmx.rmx_locks & RTV_MTU)) 2835 rt->rt_rmx.rmx_mtu = 0; 2836 } 2837 } 2838 2839 static void 2840 icmp6_redirect_timeout(rt, r) 2841 struct rtentry *rt; 2842 struct rttimer *r; 2843 { 2844 if (rt == NULL) 2845 panic("icmp6_redirect_timeout: bad route to timeout"); 2846 if ((rt->rt_flags & (RTF_GATEWAY | RTF_DYNAMIC | RTF_HOST)) == 2847 (RTF_GATEWAY | RTF_DYNAMIC | RTF_HOST)) { 2848 rtrequest((int) RTM_DELETE, (struct sockaddr *)rt_key(rt), 2849 rt->rt_gateway, rt_mask(rt), rt->rt_flags, 0); 2850 } 2851 } 2852 2853 int 2854 icmp6_sysctl(name, namelen, oldp, oldlenp, newp, newlen) 2855 int *name; 2856 u_int namelen; 2857 void *oldp; 2858 size_t *oldlenp; 2859 void *newp; 2860 size_t newlen; 2861 { 2862 2863 /* All sysctl names at this level are terminal. */ 2864 if (namelen != 1) 2865 return ENOTDIR; 2866 2867 switch (name[0]) { 2868 2869 case ICMPV6CTL_REDIRACCEPT: 2870 return sysctl_int(oldp, oldlenp, newp, newlen, 2871 &icmp6_rediraccept); 2872 case ICMPV6CTL_REDIRTIMEOUT: 2873 return sysctl_int(oldp, oldlenp, newp, newlen, 2874 &icmp6_redirtimeout); 2875 case ICMPV6CTL_STATS: 2876 return sysctl_rdstruct(oldp, oldlenp, newp, 2877 &icmp6stat, sizeof(icmp6stat)); 2878 case ICMPV6CTL_ND6_PRUNE: 2879 return sysctl_int(oldp, oldlenp, newp, newlen, &nd6_prune); 2880 case ICMPV6CTL_ND6_DELAY: 2881 return sysctl_int(oldp, oldlenp, newp, newlen, &nd6_delay); 2882 case ICMPV6CTL_ND6_UMAXTRIES: 2883 return sysctl_int(oldp, oldlenp, newp, newlen, &nd6_umaxtries); 2884 case ICMPV6CTL_ND6_MMAXTRIES: 2885 return sysctl_int(oldp, oldlenp, newp, newlen, &nd6_mmaxtries); 2886 case ICMPV6CTL_ND6_USELOOPBACK: 2887 return sysctl_int(oldp, oldlenp, newp, newlen, 2888 &nd6_useloopback); 2889 case ICMPV6CTL_NODEINFO: 2890 return sysctl_int(oldp, oldlenp, newp, newlen, &icmp6_nodeinfo); 2891 case ICMPV6CTL_ERRPPSLIMIT: 2892 return sysctl_int(oldp, oldlenp, newp, newlen, &icmp6errppslim); 2893 case ICMPV6CTL_ND6_MAXNUDHINT: 2894 return sysctl_int(oldp, oldlenp, newp, newlen, 2895 &nd6_maxnudhint); 2896 case ICMPV6CTL_MTUDISC_HIWAT: 2897 return sysctl_int(oldp, oldlenp, newp, newlen, 2898 &icmp6_mtudisc_hiwat); 2899 case ICMPV6CTL_MTUDISC_LOWAT: 2900 return sysctl_int(oldp, oldlenp, newp, newlen, 2901 &icmp6_mtudisc_lowat); 2902 case ICMPV6CTL_ND6_DEBUG: 2903 return sysctl_int(oldp, oldlenp, newp, newlen, &nd6_debug); 2904 case ICMPV6CTL_ND6_DRLIST: 2905 case ICMPV6CTL_ND6_PRLIST: 2906 return nd6_sysctl(name[0], oldp, oldlenp, newp, newlen); 2907 default: 2908 return ENOPROTOOPT; 2909 } 2910 /* NOTREACHED */ 2911 } 2912