1 /* $OpenBSD: icmp6.c,v 1.104 2009/02/22 17:43:20 claudio 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 "faith.h" 65 #include "carp.h" 66 #include "pf.h" 67 68 #include <sys/param.h> 69 #include <sys/systm.h> 70 #include <sys/malloc.h> 71 #include <sys/mbuf.h> 72 #include <sys/protosw.h> 73 #include <sys/socket.h> 74 #include <sys/socketvar.h> 75 #include <sys/time.h> 76 #include <sys/kernel.h> 77 #include <sys/syslog.h> 78 #include <sys/domain.h> 79 80 #include <net/if.h> 81 #include <net/route.h> 82 #include <net/if_dl.h> 83 #include <net/if_types.h> 84 85 #include <netinet/in.h> 86 #include <netinet/in_var.h> 87 #include <netinet/in_systm.h> 88 #include <netinet/ip.h> 89 #include <netinet/ip6.h> 90 #include <netinet6/ip6_var.h> 91 #include <netinet/icmp6.h> 92 #include <netinet6/mld6_var.h> 93 #include <netinet/in_pcb.h> 94 #include <netinet6/nd6.h> 95 #include <netinet6/in6_ifattach.h> 96 #include <netinet6/ip6protosw.h> 97 98 #if NCARP > 0 99 #include <netinet/ip_carp.h> 100 #endif 101 102 #if NPF > 0 103 #include <net/pfvar.h> 104 #endif 105 106 /* inpcb members */ 107 #define in6pcb inpcb 108 #define in6p_laddr inp_laddr6 109 #define in6p_faddr inp_faddr6 110 #define in6p_icmp6filt inp_icmp6filt 111 #define in6p_route inp_route 112 #define in6p_socket inp_socket 113 #define in6p_flags inp_flags 114 #define in6p_moptions inp_moptions6 115 #define in6p_outputopts inp_outputopts6 116 #define in6p_ip6 inp_ipv6 117 #define in6p_flowinfo inp_flowinfo 118 #define in6p_sp inp_sp 119 #define in6p_next inp_next 120 #define in6p_prev inp_prev 121 /* macro names */ 122 #define sotoin6pcb sotoinpcb 123 /* function names */ 124 #define in6_pcbdetach in_pcbdetach 125 #define in6_rtchange in_rtchange 126 127 /* 128 * for KAME src sync over BSD*'s. XXX: FreeBSD (>=3) are VERY different from 129 * others... 130 */ 131 #define in6p_ip6_nxt inp_ipv6.ip6_nxt 132 133 extern struct domain inet6domain; 134 extern struct ip6protosw inet6sw[]; 135 extern u_char ip6_protox[]; 136 137 struct icmp6stat icmp6stat; 138 139 extern struct inpcbtable rawin6pcbtable; 140 extern int icmp6errppslim; 141 static int icmp6errpps_count = 0; 142 static struct timeval icmp6errppslim_last; 143 extern int icmp6_nodeinfo; 144 145 /* 146 * List of callbacks to notify when Path MTU changes are made. 147 */ 148 struct icmp6_mtudisc_callback { 149 LIST_ENTRY(icmp6_mtudisc_callback) mc_list; 150 void (*mc_func)(struct in6_addr *); 151 }; 152 153 LIST_HEAD(, icmp6_mtudisc_callback) icmp6_mtudisc_callbacks = 154 LIST_HEAD_INITIALIZER(&icmp6_mtudisc_callbacks); 155 156 static struct rttimer_queue *icmp6_mtudisc_timeout_q = NULL; 157 extern int pmtu_expire; 158 159 /* XXX do these values make any sense? */ 160 static int icmp6_mtudisc_hiwat = 1280; 161 static int icmp6_mtudisc_lowat = 256; 162 163 /* 164 * keep track of # of redirect routes. 165 */ 166 static struct rttimer_queue *icmp6_redirect_timeout_q = NULL; 167 168 /* XXX experimental, turned off */ 169 static int icmp6_redirect_lowat = -1; 170 171 static void icmp6_errcount(struct icmp6errstat *, int, int); 172 static int icmp6_rip6_input(struct mbuf **, int); 173 static int icmp6_ratelimit(const struct in6_addr *, const int, const int); 174 static const char *icmp6_redirect_diag(struct in6_addr *, 175 struct in6_addr *, struct in6_addr *); 176 static struct mbuf *ni6_input(struct mbuf *, int); 177 static struct mbuf *ni6_nametodns(const char *, int, int); 178 static int ni6_dnsmatch(const char *, int, const char *, int); 179 static int ni6_addrs(struct icmp6_nodeinfo *, struct mbuf *, 180 struct ifnet **, char *); 181 static int ni6_store_addrs(struct icmp6_nodeinfo *, struct icmp6_nodeinfo *, 182 struct ifnet *, int); 183 static int icmp6_notify_error(struct mbuf *, int, int, int); 184 static struct rtentry *icmp6_mtudisc_clone(struct sockaddr *); 185 static void icmp6_mtudisc_timeout(struct rtentry *, struct rttimer *); 186 static void icmp6_redirect_timeout(struct rtentry *, struct rttimer *); 187 188 void 189 icmp6_init() 190 { 191 mld6_init(); 192 icmp6_mtudisc_timeout_q = rt_timer_queue_create(pmtu_expire); 193 icmp6_redirect_timeout_q = rt_timer_queue_create(icmp6_redirtimeout); 194 } 195 196 static void 197 icmp6_errcount(struct icmp6errstat *stat, int type, int code) 198 { 199 switch (type) { 200 case ICMP6_DST_UNREACH: 201 switch (code) { 202 case ICMP6_DST_UNREACH_NOROUTE: 203 stat->icp6errs_dst_unreach_noroute++; 204 return; 205 case ICMP6_DST_UNREACH_ADMIN: 206 stat->icp6errs_dst_unreach_admin++; 207 return; 208 case ICMP6_DST_UNREACH_BEYONDSCOPE: 209 stat->icp6errs_dst_unreach_beyondscope++; 210 return; 211 case ICMP6_DST_UNREACH_ADDR: 212 stat->icp6errs_dst_unreach_addr++; 213 return; 214 case ICMP6_DST_UNREACH_NOPORT: 215 stat->icp6errs_dst_unreach_noport++; 216 return; 217 } 218 break; 219 case ICMP6_PACKET_TOO_BIG: 220 stat->icp6errs_packet_too_big++; 221 return; 222 case ICMP6_TIME_EXCEEDED: 223 switch (code) { 224 case ICMP6_TIME_EXCEED_TRANSIT: 225 stat->icp6errs_time_exceed_transit++; 226 return; 227 case ICMP6_TIME_EXCEED_REASSEMBLY: 228 stat->icp6errs_time_exceed_reassembly++; 229 return; 230 } 231 break; 232 case ICMP6_PARAM_PROB: 233 switch (code) { 234 case ICMP6_PARAMPROB_HEADER: 235 stat->icp6errs_paramprob_header++; 236 return; 237 case ICMP6_PARAMPROB_NEXTHEADER: 238 stat->icp6errs_paramprob_nextheader++; 239 return; 240 case ICMP6_PARAMPROB_OPTION: 241 stat->icp6errs_paramprob_option++; 242 return; 243 } 244 break; 245 case ND_REDIRECT: 246 stat->icp6errs_redirect++; 247 return; 248 } 249 stat->icp6errs_unknown++; 250 } 251 252 /* 253 * Register a Path MTU Discovery callback. 254 */ 255 void 256 icmp6_mtudisc_callback_register(void (*func)(struct in6_addr *)) 257 { 258 struct icmp6_mtudisc_callback *mc; 259 260 for (mc = LIST_FIRST(&icmp6_mtudisc_callbacks); mc != NULL; 261 mc = LIST_NEXT(mc, mc_list)) { 262 if (mc->mc_func == func) 263 return; 264 } 265 266 mc = malloc(sizeof(*mc), M_PCB, M_NOWAIT); 267 if (mc == NULL) 268 panic("icmp6_mtudisc_callback_register"); 269 270 mc->mc_func = func; 271 LIST_INSERT_HEAD(&icmp6_mtudisc_callbacks, mc, mc_list); 272 } 273 274 /* 275 * Generate an error packet of type error in response to bad IP6 packet. 276 */ 277 void 278 icmp6_error(struct mbuf *m, int type, int code, int param) 279 { 280 struct ip6_hdr *oip6, *nip6; 281 struct icmp6_hdr *icmp6; 282 u_int preplen; 283 int off; 284 int nxt; 285 286 icmp6stat.icp6s_error++; 287 288 /* count per-type-code statistics */ 289 icmp6_errcount(&icmp6stat.icp6s_outerrhist, type, code); 290 291 if (m->m_len < sizeof(struct ip6_hdr)) { 292 m = m_pullup(m, sizeof(struct ip6_hdr)); 293 if (m == NULL) 294 return; 295 } 296 oip6 = mtod(m, struct ip6_hdr *); 297 298 /* 299 * If the destination address of the erroneous packet is a multicast 300 * address, or the packet was sent using link-layer multicast, 301 * we should basically suppress sending an error (RFC 2463, Section 302 * 2.4). 303 * We have two exceptions (the item e.2 in that section): 304 * - the Pakcet Too Big message can be sent for path MTU discovery. 305 * - the Parameter Problem Message that can be allowed an icmp6 error 306 * in the option type field. This check has been done in 307 * ip6_unknown_opt(), so we can just check the type and code. 308 */ 309 if ((m->m_flags & (M_BCAST|M_MCAST) || 310 IN6_IS_ADDR_MULTICAST(&oip6->ip6_dst)) && 311 (type != ICMP6_PACKET_TOO_BIG && 312 (type != ICMP6_PARAM_PROB || 313 code != ICMP6_PARAMPROB_OPTION))) 314 goto freeit; 315 316 /* 317 * RFC 2463, 2.4 (e.5): source address check. 318 * XXX: the case of anycast source? 319 */ 320 if (IN6_IS_ADDR_UNSPECIFIED(&oip6->ip6_src) || 321 IN6_IS_ADDR_MULTICAST(&oip6->ip6_src)) 322 goto freeit; 323 324 /* 325 * If we are about to send ICMPv6 against ICMPv6 error/redirect, 326 * don't do it. 327 */ 328 nxt = -1; 329 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); 330 if (off >= 0 && nxt == IPPROTO_ICMPV6) { 331 struct icmp6_hdr *icp; 332 333 IP6_EXTHDR_GET(icp, struct icmp6_hdr *, m, off, 334 sizeof(*icp)); 335 if (icp == NULL) { 336 icmp6stat.icp6s_tooshort++; 337 return; 338 } 339 if (icp->icmp6_type < ICMP6_ECHO_REQUEST || 340 icp->icmp6_type == ND_REDIRECT) { 341 /* 342 * ICMPv6 error 343 * Special case: for redirect (which is 344 * informational) we must not send icmp6 error. 345 */ 346 icmp6stat.icp6s_canterror++; 347 goto freeit; 348 } else { 349 /* ICMPv6 informational - send the error */ 350 } 351 } 352 else { 353 /* non-ICMPv6 - send the error */ 354 } 355 356 oip6 = mtod(m, struct ip6_hdr *); /* adjust pointer */ 357 358 /* Finally, do rate limitation check. */ 359 if (icmp6_ratelimit(&oip6->ip6_src, type, code)) { 360 icmp6stat.icp6s_toofreq++; 361 goto freeit; 362 } 363 364 /* 365 * OK, ICMP6 can be generated. 366 */ 367 368 if (m->m_pkthdr.len >= ICMPV6_PLD_MAXLEN) 369 m_adj(m, ICMPV6_PLD_MAXLEN - m->m_pkthdr.len); 370 371 preplen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 372 M_PREPEND(m, preplen, M_DONTWAIT); 373 if (m && m->m_len < preplen) 374 m = m_pullup(m, preplen); 375 if (m == NULL) { 376 nd6log((LOG_DEBUG, "ENOBUFS in icmp6_error %d\n", __LINE__)); 377 return; 378 } 379 380 nip6 = mtod(m, struct ip6_hdr *); 381 nip6->ip6_src = oip6->ip6_src; 382 nip6->ip6_dst = oip6->ip6_dst; 383 384 if (IN6_IS_SCOPE_EMBED(&oip6->ip6_src)) 385 oip6->ip6_src.s6_addr16[1] = 0; 386 if (IN6_IS_SCOPE_EMBED(&oip6->ip6_dst)) 387 oip6->ip6_dst.s6_addr16[1] = 0; 388 389 icmp6 = (struct icmp6_hdr *)(nip6 + 1); 390 icmp6->icmp6_type = type; 391 icmp6->icmp6_code = code; 392 icmp6->icmp6_pptr = htonl((u_int32_t)param); 393 394 /* 395 * icmp6_reflect() is designed to be in the input path. 396 * icmp6_error() can be called from both input and outut path, 397 * and if we are in output path rcvif could contain bogus value. 398 * clear m->m_pkthdr.rcvif for safety, we should have enough scope 399 * information in ip header (nip6). 400 */ 401 m->m_pkthdr.rcvif = NULL; 402 403 icmp6stat.icp6s_outhist[type]++; 404 icmp6_reflect(m, sizeof(struct ip6_hdr)); /* header order: IPv6 - ICMPv6 */ 405 406 return; 407 408 freeit: 409 /* 410 * If we can't tell wheter or not we can generate ICMP6, free it. 411 */ 412 m_freem(m); 413 } 414 415 /* 416 * Process a received ICMP6 message. 417 */ 418 int 419 icmp6_input(struct mbuf **mp, int *offp, int proto) 420 { 421 struct mbuf *m = *mp, *n; 422 struct ip6_hdr *ip6, *nip6; 423 struct icmp6_hdr *icmp6, *nicmp6; 424 int off = *offp; 425 int icmp6len = m->m_pkthdr.len - *offp; 426 int code, sum, noff; 427 428 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_msg); 429 430 /* 431 * Locate icmp6 structure in mbuf, and check 432 * that not corrupted and of at least minimum length 433 */ 434 435 ip6 = mtod(m, struct ip6_hdr *); 436 if (icmp6len < sizeof(struct icmp6_hdr)) { 437 icmp6stat.icp6s_tooshort++; 438 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_error); 439 goto freeit; 440 } 441 442 /* 443 * calculate the checksum 444 */ 445 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 446 if (icmp6 == NULL) { 447 icmp6stat.icp6s_tooshort++; 448 return IPPROTO_DONE; 449 } 450 code = icmp6->icmp6_code; 451 452 if ((sum = in6_cksum(m, IPPROTO_ICMPV6, off, icmp6len)) != 0) { 453 nd6log((LOG_ERR, 454 "ICMP6 checksum error(%d|%x) %s\n", 455 icmp6->icmp6_type, sum, ip6_sprintf(&ip6->ip6_src))); 456 icmp6stat.icp6s_checksum++; 457 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_error); 458 goto freeit; 459 } 460 461 #if defined(NFAITH) && 0 < NFAITH 462 if (m->m_pkthdr.rcvif && m->m_pkthdr.rcvif->if_type == IFT_FAITH) { 463 /* 464 * Deliver very specific ICMP6 type only. 465 * This is important to deliver TOOBIG. Otherwise PMTUD 466 * will not work. 467 */ 468 switch (icmp6->icmp6_type) { 469 case ICMP6_DST_UNREACH: 470 case ICMP6_PACKET_TOO_BIG: 471 case ICMP6_TIME_EXCEEDED: 472 break; 473 default: 474 goto freeit; 475 } 476 } 477 #endif 478 479 #if NCARP > 0 480 if (m->m_pkthdr.rcvif->if_type == IFT_CARP && 481 icmp6->icmp6_type == ICMP6_ECHO_REQUEST && 482 carp_lsdrop(m, AF_INET6, ip6->ip6_src.s6_addr32, 483 ip6->ip6_dst.s6_addr32)) 484 goto freeit; 485 #endif 486 icmp6stat.icp6s_inhist[icmp6->icmp6_type]++; 487 488 switch (icmp6->icmp6_type) { 489 case ICMP6_DST_UNREACH: 490 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_dstunreach); 491 switch (code) { 492 case ICMP6_DST_UNREACH_NOROUTE: 493 code = PRC_UNREACH_NET; 494 break; 495 case ICMP6_DST_UNREACH_ADMIN: 496 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_adminprohib); 497 code = PRC_UNREACH_PROTOCOL; /* is this a good code? */ 498 break; 499 case ICMP6_DST_UNREACH_ADDR: 500 code = PRC_HOSTDEAD; 501 break; 502 #ifdef COMPAT_RFC1885 503 case ICMP6_DST_UNREACH_NOTNEIGHBOR: 504 code = PRC_UNREACH_SRCFAIL; 505 break; 506 #else 507 case ICMP6_DST_UNREACH_BEYONDSCOPE: 508 /* I mean "source address was incorrect." */ 509 code = PRC_PARAMPROB; 510 break; 511 #endif 512 case ICMP6_DST_UNREACH_NOPORT: 513 code = PRC_UNREACH_PORT; 514 break; 515 default: 516 goto badcode; 517 } 518 goto deliver; 519 520 case ICMP6_PACKET_TOO_BIG: 521 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_pkttoobig); 522 523 /* MTU is checked in icmp6_mtudisc_update. */ 524 code = PRC_MSGSIZE; 525 526 /* 527 * Updating the path MTU will be done after examining 528 * intermediate extension headers. 529 */ 530 goto deliver; 531 532 case ICMP6_TIME_EXCEEDED: 533 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_timeexceed); 534 switch (code) { 535 case ICMP6_TIME_EXCEED_TRANSIT: 536 code = PRC_TIMXCEED_INTRANS; 537 break; 538 case ICMP6_TIME_EXCEED_REASSEMBLY: 539 code = PRC_TIMXCEED_REASS; 540 break; 541 default: 542 goto badcode; 543 } 544 goto deliver; 545 546 case ICMP6_PARAM_PROB: 547 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_paramprob); 548 switch (code) { 549 case ICMP6_PARAMPROB_NEXTHEADER: 550 code = PRC_UNREACH_PROTOCOL; 551 break; 552 case ICMP6_PARAMPROB_HEADER: 553 case ICMP6_PARAMPROB_OPTION: 554 code = PRC_PARAMPROB; 555 break; 556 default: 557 goto badcode; 558 } 559 goto deliver; 560 561 case ICMP6_ECHO_REQUEST: 562 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echo); 563 if (code != 0) 564 goto badcode; 565 /* 566 * Copy mbuf to send to two data paths: userland socket(s), 567 * and to the querier (echo reply). 568 * m: a copy for socket, n: a copy for querier 569 */ 570 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 571 /* Give up local */ 572 n = m; 573 m = NULL; 574 goto deliverecho; 575 } 576 /* 577 * If the first mbuf is shared, or the first mbuf is too short, 578 * copy the first part of the data into a fresh mbuf. 579 * Otherwise, we will wrongly overwrite both copies. 580 */ 581 if ((n->m_flags & M_EXT) != 0 || 582 n->m_len < off + sizeof(struct icmp6_hdr)) { 583 struct mbuf *n0 = n; 584 const int maxlen = sizeof(*nip6) + sizeof(*nicmp6); 585 586 /* 587 * Prepare an internal mbuf. m_pullup() doesn't 588 * always copy the length we specified. 589 */ 590 if (maxlen >= MCLBYTES) { 591 /* Give up remote */ 592 m_freem(n0); 593 break; 594 } 595 MGETHDR(n, M_DONTWAIT, n0->m_type); 596 if (n && maxlen >= MHLEN) { 597 MCLGET(n, M_DONTWAIT); 598 if ((n->m_flags & M_EXT) == 0) { 599 m_free(n); 600 n = NULL; 601 } 602 } 603 if (n == NULL) { 604 /* Give up local */ 605 m_freem(n0); 606 n = m; 607 m = NULL; 608 goto deliverecho; 609 } 610 M_MOVE_PKTHDR(n, n0); 611 /* 612 * Copy IPv6 and ICMPv6 only. 613 */ 614 nip6 = mtod(n, struct ip6_hdr *); 615 bcopy(ip6, nip6, sizeof(struct ip6_hdr)); 616 nicmp6 = (struct icmp6_hdr *)(nip6 + 1); 617 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr)); 618 noff = sizeof(struct ip6_hdr); 619 n->m_len = noff + sizeof(struct icmp6_hdr); 620 /* 621 * Adjust mbuf. ip6_plen will be adjusted in 622 * ip6_output(). 623 * n->m_pkthdr.len == n0->m_pkthdr.len at this point. 624 */ 625 n->m_pkthdr.len += noff + sizeof(struct icmp6_hdr); 626 n->m_pkthdr.len -= (off + sizeof(struct icmp6_hdr)); 627 m_adj(n0, off + sizeof(struct icmp6_hdr)); 628 n->m_next = n0; 629 } else { 630 deliverecho: 631 nip6 = mtod(n, struct ip6_hdr *); 632 IP6_EXTHDR_GET(nicmp6, struct icmp6_hdr *, n, off, 633 sizeof(*nicmp6)); 634 noff = off; 635 } 636 nicmp6->icmp6_type = ICMP6_ECHO_REPLY; 637 nicmp6->icmp6_code = 0; 638 if (n) { 639 icmp6stat.icp6s_reflect++; 640 icmp6stat.icp6s_outhist[ICMP6_ECHO_REPLY]++; 641 icmp6_reflect(n, noff); 642 } 643 if (!m) 644 goto freeit; 645 break; 646 647 case ICMP6_ECHO_REPLY: 648 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echoreply); 649 if (code != 0) 650 goto badcode; 651 break; 652 653 case MLD_LISTENER_QUERY: 654 case MLD_LISTENER_REPORT: 655 if (icmp6len < sizeof(struct mld_hdr)) 656 goto badlen; 657 if (icmp6->icmp6_type == MLD_LISTENER_QUERY) /* XXX: ugly... */ 658 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldquery); 659 else 660 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldreport); 661 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 662 /* give up local */ 663 mld6_input(m, off); 664 m = NULL; 665 goto freeit; 666 } 667 mld6_input(n, off); 668 /* m stays. */ 669 break; 670 671 case MLD_LISTENER_DONE: 672 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mlddone); 673 if (icmp6len < sizeof(struct mld_hdr)) /* necessary? */ 674 goto badlen; 675 break; /* nothing to be done in kernel */ 676 677 case MLD_MTRACE_RESP: 678 case MLD_MTRACE: 679 /* XXX: these two are experimental. not officially defined. */ 680 /* XXX: per-interface statistics? */ 681 break; /* just pass it to applications */ 682 683 case ICMP6_WRUREQUEST: /* ICMP6_FQDN_QUERY */ 684 { 685 enum { WRU, FQDN } mode; 686 687 if (!icmp6_nodeinfo) 688 break; 689 690 if (icmp6len == sizeof(struct icmp6_hdr) + 4) 691 mode = WRU; 692 else if (icmp6len >= sizeof(struct icmp6_nodeinfo)) 693 mode = FQDN; 694 else 695 goto badlen; 696 697 if (mode == FQDN) { 698 n = m_copym(m, 0, M_COPYALL, M_DONTWAIT); 699 if (n) 700 n = ni6_input(n, off); 701 /* XXX meaningless if n == NULL */ 702 noff = sizeof(struct ip6_hdr); 703 } else { 704 u_char *p; 705 int maxlen, maxhlen; 706 707 if ((icmp6_nodeinfo & 1) == 0) 708 break; 709 710 if (code != 0) 711 goto badcode; 712 maxlen = sizeof(*nip6) + sizeof(*nicmp6) + 4; 713 if (maxlen >= MCLBYTES) { 714 /* Give up remote */ 715 break; 716 } 717 MGETHDR(n, M_DONTWAIT, m->m_type); 718 if (n && maxlen > MHLEN) { 719 MCLGET(n, M_DONTWAIT); 720 if ((n->m_flags & M_EXT) == 0) { 721 m_free(n); 722 n = NULL; 723 } 724 } 725 if (n == NULL) { 726 /* Give up remote */ 727 break; 728 } 729 n->m_pkthdr.rcvif = NULL; 730 n->m_len = 0; 731 maxhlen = M_TRAILINGSPACE(n) - maxlen; 732 if (maxhlen > hostnamelen) 733 maxhlen = hostnamelen; 734 /* 735 * Copy IPv6 and ICMPv6 only. 736 */ 737 nip6 = mtod(n, struct ip6_hdr *); 738 bcopy(ip6, nip6, sizeof(struct ip6_hdr)); 739 nicmp6 = (struct icmp6_hdr *)(nip6 + 1); 740 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr)); 741 p = (u_char *)(nicmp6 + 1); 742 bzero(p, 4); 743 bcopy(hostname, p + 4, maxhlen); /* meaningless TTL */ 744 noff = sizeof(struct ip6_hdr); 745 M_DUP_PKTHDR(n, m); /* just for rcvif */ 746 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) + 747 sizeof(struct icmp6_hdr) + 4 + maxhlen; 748 nicmp6->icmp6_type = ICMP6_WRUREPLY; 749 nicmp6->icmp6_code = 0; 750 } 751 #undef hostnamelen 752 if (n) { 753 icmp6stat.icp6s_reflect++; 754 icmp6stat.icp6s_outhist[ICMP6_WRUREPLY]++; 755 icmp6_reflect(n, noff); 756 } 757 break; 758 } 759 760 case ICMP6_WRUREPLY: 761 if (code != 0) 762 goto badcode; 763 break; 764 765 case ND_ROUTER_SOLICIT: 766 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routersolicit); 767 if (code != 0) 768 goto badcode; 769 if (icmp6len < sizeof(struct nd_router_solicit)) 770 goto badlen; 771 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 772 /* give up local */ 773 nd6_rs_input(m, off, icmp6len); 774 m = NULL; 775 goto freeit; 776 } 777 nd6_rs_input(n, off, icmp6len); 778 /* m stays. */ 779 break; 780 781 case ND_ROUTER_ADVERT: 782 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routeradvert); 783 if (code != 0) 784 goto badcode; 785 if (icmp6len < sizeof(struct nd_router_advert)) 786 goto badlen; 787 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 788 /* give up local */ 789 nd6_ra_input(m, off, icmp6len); 790 m = NULL; 791 goto freeit; 792 } 793 nd6_ra_input(n, off, icmp6len); 794 /* m stays. */ 795 break; 796 797 case ND_NEIGHBOR_SOLICIT: 798 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighborsolicit); 799 if (code != 0) 800 goto badcode; 801 if (icmp6len < sizeof(struct nd_neighbor_solicit)) 802 goto badlen; 803 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 804 /* give up local */ 805 nd6_ns_input(m, off, icmp6len); 806 m = NULL; 807 goto freeit; 808 } 809 nd6_ns_input(n, off, icmp6len); 810 /* m stays. */ 811 break; 812 813 case ND_NEIGHBOR_ADVERT: 814 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighboradvert); 815 if (code != 0) 816 goto badcode; 817 if (icmp6len < sizeof(struct nd_neighbor_advert)) 818 goto badlen; 819 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 820 /* give up local */ 821 nd6_na_input(m, off, icmp6len); 822 m = NULL; 823 goto freeit; 824 } 825 nd6_na_input(n, off, icmp6len); 826 /* m stays. */ 827 break; 828 829 case ND_REDIRECT: 830 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_redirect); 831 if (code != 0) 832 goto badcode; 833 if (icmp6len < sizeof(struct nd_redirect)) 834 goto badlen; 835 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 836 /* give up local */ 837 icmp6_redirect_input(m, off); 838 m = NULL; 839 goto freeit; 840 } 841 icmp6_redirect_input(n, off); 842 /* m stays. */ 843 break; 844 845 case ICMP6_ROUTER_RENUMBERING: 846 if (code != ICMP6_ROUTER_RENUMBERING_COMMAND && 847 code != ICMP6_ROUTER_RENUMBERING_RESULT) 848 goto badcode; 849 if (icmp6len < sizeof(struct icmp6_router_renum)) 850 goto badlen; 851 break; 852 853 default: 854 nd6log((LOG_DEBUG, 855 "icmp6_input: unknown type %d(src=%s, dst=%s, ifid=%d)\n", 856 icmp6->icmp6_type, ip6_sprintf(&ip6->ip6_src), 857 ip6_sprintf(&ip6->ip6_dst), 858 m->m_pkthdr.rcvif ? m->m_pkthdr.rcvif->if_index : 0)); 859 if (icmp6->icmp6_type < ICMP6_ECHO_REQUEST) { 860 /* ICMPv6 error: MUST deliver it by spec... */ 861 code = PRC_NCMDS; 862 /* deliver */ 863 } else { 864 /* ICMPv6 informational: MUST not deliver */ 865 break; 866 } 867 deliver: 868 if (icmp6_notify_error(m, off, icmp6len, code)) { 869 /* In this case, m should've been freed. */ 870 return (IPPROTO_DONE); 871 } 872 break; 873 874 badcode: 875 icmp6stat.icp6s_badcode++; 876 break; 877 878 badlen: 879 icmp6stat.icp6s_badlen++; 880 break; 881 } 882 883 /* deliver the packet to appropriate sockets */ 884 icmp6_rip6_input(&m, *offp); 885 886 return IPPROTO_DONE; 887 888 freeit: 889 m_freem(m); 890 return IPPROTO_DONE; 891 } 892 893 static int 894 icmp6_notify_error(struct mbuf *m, int off, int icmp6len, int code) 895 { 896 struct icmp6_hdr *icmp6; 897 struct ip6_hdr *eip6; 898 u_int32_t notifymtu; 899 struct sockaddr_in6 icmp6src, icmp6dst; 900 901 if (icmp6len < sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr)) { 902 icmp6stat.icp6s_tooshort++; 903 goto freeit; 904 } 905 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, 906 sizeof(*icmp6) + sizeof(struct ip6_hdr)); 907 if (icmp6 == NULL) { 908 icmp6stat.icp6s_tooshort++; 909 return (-1); 910 } 911 eip6 = (struct ip6_hdr *)(icmp6 + 1); 912 913 /* Detect the upper level protocol */ 914 { 915 void (*ctlfunc)(int, struct sockaddr *, void *); 916 u_int8_t nxt = eip6->ip6_nxt; 917 int eoff = off + sizeof(struct icmp6_hdr) + 918 sizeof(struct ip6_hdr); 919 struct ip6ctlparam ip6cp; 920 struct in6_addr *finaldst = NULL; 921 int icmp6type = icmp6->icmp6_type; 922 struct ip6_frag *fh; 923 struct ip6_rthdr *rth; 924 struct ip6_rthdr0 *rth0; 925 int rthlen; 926 927 while (1) { /* XXX: should avoid infinite loop explicitly? */ 928 struct ip6_ext *eh; 929 930 switch (nxt) { 931 case IPPROTO_HOPOPTS: 932 case IPPROTO_DSTOPTS: 933 case IPPROTO_AH: 934 IP6_EXTHDR_GET(eh, struct ip6_ext *, m, 935 eoff, sizeof(*eh)); 936 if (eh == NULL) { 937 icmp6stat.icp6s_tooshort++; 938 return (-1); 939 } 940 941 if (nxt == IPPROTO_AH) 942 eoff += (eh->ip6e_len + 2) << 2; 943 else 944 eoff += (eh->ip6e_len + 1) << 3; 945 nxt = eh->ip6e_nxt; 946 break; 947 case IPPROTO_ROUTING: 948 /* 949 * When the erroneous packet contains a 950 * routing header, we should examine the 951 * header to determine the final destination. 952 * Otherwise, we can't properly update 953 * information that depends on the final 954 * destination (e.g. path MTU). 955 */ 956 IP6_EXTHDR_GET(rth, struct ip6_rthdr *, m, 957 eoff, sizeof(*rth)); 958 if (rth == NULL) { 959 icmp6stat.icp6s_tooshort++; 960 return (-1); 961 } 962 rthlen = (rth->ip6r_len + 1) << 3; 963 /* 964 * XXX: currently there is no 965 * officially defined type other 966 * than type-0. 967 * Note that if the segment left field 968 * is 0, all intermediate hops must 969 * have been passed. 970 */ 971 if (rth->ip6r_segleft && 972 rth->ip6r_type == IPV6_RTHDR_TYPE_0) { 973 int hops; 974 975 IP6_EXTHDR_GET(rth0, 976 struct ip6_rthdr0 *, m, 977 eoff, rthlen); 978 if (rth0 == NULL) { 979 icmp6stat.icp6s_tooshort++; 980 return (-1); 981 } 982 /* just ignore a bogus header */ 983 if ((rth0->ip6r0_len % 2) == 0 && 984 (hops = rth0->ip6r0_len/2)) 985 finaldst = (struct in6_addr *)(rth0 + 1) + (hops - 1); 986 } 987 eoff += rthlen; 988 nxt = rth->ip6r_nxt; 989 break; 990 case IPPROTO_FRAGMENT: 991 IP6_EXTHDR_GET(fh, struct ip6_frag *, m, 992 eoff, sizeof(*fh)); 993 if (fh == NULL) { 994 icmp6stat.icp6s_tooshort++; 995 return (-1); 996 } 997 /* 998 * Data after a fragment header is meaningless 999 * unless it is the first fragment, but 1000 * we'll go to the notify label for path MTU 1001 * discovery. 1002 */ 1003 if (fh->ip6f_offlg & IP6F_OFF_MASK) 1004 goto notify; 1005 1006 eoff += sizeof(struct ip6_frag); 1007 nxt = fh->ip6f_nxt; 1008 break; 1009 default: 1010 /* 1011 * This case includes ESP and the No Next 1012 * Header. In such cases going to the notify 1013 * label does not have any meaning 1014 * (i.e. ctlfunc will be NULL), but we go 1015 * anyway since we might have to update 1016 * path MTU information. 1017 */ 1018 goto notify; 1019 } 1020 } 1021 notify: 1022 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, 1023 sizeof(*icmp6) + sizeof(struct ip6_hdr)); 1024 if (icmp6 == NULL) { 1025 icmp6stat.icp6s_tooshort++; 1026 return (-1); 1027 } 1028 1029 eip6 = (struct ip6_hdr *)(icmp6 + 1); 1030 bzero(&icmp6dst, sizeof(icmp6dst)); 1031 icmp6dst.sin6_len = sizeof(struct sockaddr_in6); 1032 icmp6dst.sin6_family = AF_INET6; 1033 if (finaldst == NULL) 1034 icmp6dst.sin6_addr = eip6->ip6_dst; 1035 else 1036 icmp6dst.sin6_addr = *finaldst; 1037 icmp6dst.sin6_scope_id = in6_addr2scopeid(m->m_pkthdr.rcvif, 1038 &icmp6dst.sin6_addr); 1039 if (in6_embedscope(&icmp6dst.sin6_addr, &icmp6dst, 1040 NULL, NULL)) { 1041 /* should be impossbile */ 1042 nd6log((LOG_DEBUG, 1043 "icmp6_notify_error: in6_embedscope failed\n")); 1044 goto freeit; 1045 } 1046 1047 /* 1048 * retrieve parameters from the inner IPv6 header, and convert 1049 * them into sockaddr structures. 1050 */ 1051 bzero(&icmp6src, sizeof(icmp6src)); 1052 icmp6src.sin6_len = sizeof(struct sockaddr_in6); 1053 icmp6src.sin6_family = AF_INET6; 1054 icmp6src.sin6_addr = eip6->ip6_src; 1055 icmp6src.sin6_scope_id = in6_addr2scopeid(m->m_pkthdr.rcvif, 1056 &icmp6src.sin6_addr); 1057 if (in6_embedscope(&icmp6src.sin6_addr, &icmp6src, 1058 NULL, NULL)) { 1059 /* should be impossbile */ 1060 nd6log((LOG_DEBUG, 1061 "icmp6_notify_error: in6_embedscope failed\n")); 1062 goto freeit; 1063 } 1064 icmp6src.sin6_flowinfo = 1065 (eip6->ip6_flow & IPV6_FLOWLABEL_MASK); 1066 1067 if (finaldst == NULL) 1068 finaldst = &eip6->ip6_dst; 1069 ip6cp.ip6c_m = m; 1070 ip6cp.ip6c_icmp6 = icmp6; 1071 ip6cp.ip6c_ip6 = (struct ip6_hdr *)(icmp6 + 1); 1072 ip6cp.ip6c_off = eoff; 1073 ip6cp.ip6c_finaldst = finaldst; 1074 ip6cp.ip6c_src = &icmp6src; 1075 ip6cp.ip6c_nxt = nxt; 1076 #if NPF > 0 1077 pf_pkt_addr_changed(m); 1078 #endif 1079 1080 if (icmp6type == ICMP6_PACKET_TOO_BIG) { 1081 notifymtu = ntohl(icmp6->icmp6_mtu); 1082 ip6cp.ip6c_cmdarg = (void *)¬ifymtu; 1083 } 1084 1085 ctlfunc = (void (*)(int, struct sockaddr *, void *)) 1086 (inet6sw[ip6_protox[nxt]].pr_ctlinput); 1087 if (ctlfunc) { 1088 (void) (*ctlfunc)(code, (struct sockaddr *)&icmp6dst, 1089 &ip6cp); 1090 } 1091 } 1092 return (0); 1093 1094 freeit: 1095 m_freem(m); 1096 return (-1); 1097 } 1098 1099 void 1100 icmp6_mtudisc_update(struct ip6ctlparam *ip6cp, int validated) 1101 { 1102 unsigned long rtcount; 1103 struct icmp6_mtudisc_callback *mc; 1104 struct in6_addr *dst = ip6cp->ip6c_finaldst; 1105 struct icmp6_hdr *icmp6 = ip6cp->ip6c_icmp6; 1106 struct mbuf *m = ip6cp->ip6c_m; /* will be necessary for scope issue */ 1107 u_int mtu = ntohl(icmp6->icmp6_mtu); 1108 struct rtentry *rt = NULL; 1109 struct sockaddr_in6 sin6; 1110 1111 /* 1112 * The MTU may not be less then the minimal IPv6 MTU except for the 1113 * hack in ip6_output/ip6_setpmtu where we always include a frag header. 1114 */ 1115 if (mtu < IPV6_MMTU - sizeof(struct ip6_frag)) 1116 return; 1117 1118 /* 1119 * allow non-validated cases if memory is plenty, to make traffic 1120 * from non-connected pcb happy. 1121 */ 1122 rtcount = rt_timer_count(icmp6_mtudisc_timeout_q); 1123 if (validated) { 1124 if (0 <= icmp6_mtudisc_hiwat && rtcount > icmp6_mtudisc_hiwat) 1125 return; 1126 else if (0 <= icmp6_mtudisc_lowat && 1127 rtcount > icmp6_mtudisc_lowat) { 1128 /* 1129 * XXX nuke a victim, install the new one. 1130 */ 1131 } 1132 } else { 1133 if (0 <= icmp6_mtudisc_lowat && rtcount > icmp6_mtudisc_lowat) 1134 return; 1135 } 1136 1137 bzero(&sin6, sizeof(sin6)); 1138 sin6.sin6_family = PF_INET6; 1139 sin6.sin6_len = sizeof(struct sockaddr_in6); 1140 sin6.sin6_addr = *dst; 1141 /* XXX normally, this won't happen */ 1142 if (IN6_IS_ADDR_LINKLOCAL(dst)) { 1143 sin6.sin6_addr.s6_addr16[1] = 1144 htons(m->m_pkthdr.rcvif->if_index); 1145 } 1146 /* sin6.sin6_scope_id = XXX: should be set if DST is a scoped addr */ 1147 rt = icmp6_mtudisc_clone((struct sockaddr *)&sin6); 1148 1149 if (rt && (rt->rt_flags & RTF_HOST) && 1150 !(rt->rt_rmx.rmx_locks & RTV_MTU) && 1151 (rt->rt_rmx.rmx_mtu > mtu || rt->rt_rmx.rmx_mtu == 0)) { 1152 if (mtu < IN6_LINKMTU(rt->rt_ifp)) { 1153 icmp6stat.icp6s_pmtuchg++; 1154 rt->rt_rmx.rmx_mtu = mtu; 1155 } 1156 } 1157 if (rt) { /* XXX: need braces to avoid conflict with else in RTFREE. */ 1158 RTFREE(rt); 1159 } 1160 1161 /* 1162 * Notify protocols that the MTU for this destination 1163 * has changed. 1164 */ 1165 for (mc = LIST_FIRST(&icmp6_mtudisc_callbacks); mc != NULL; 1166 mc = LIST_NEXT(mc, mc_list)) 1167 (*mc->mc_func)(&sin6.sin6_addr); 1168 } 1169 1170 /* 1171 * Process a Node Information Query packet, based on 1172 * draft-ietf-ipngwg-icmp-name-lookups-07. 1173 * 1174 * Spec incompatibilities: 1175 * - IPv6 Subject address handling 1176 * - IPv4 Subject address handling support missing 1177 * - Proxy reply (answer even if it's not for me) 1178 * - joins NI group address at in6_ifattach() time only, does not cope 1179 * with hostname changes by sethostname(3) 1180 */ 1181 #ifndef offsetof /* XXX */ 1182 #define offsetof(type, member) ((size_t)(&((type *)0)->member)) 1183 #endif 1184 static struct mbuf * 1185 ni6_input(struct mbuf *m, int off) 1186 { 1187 struct icmp6_nodeinfo *ni6, *nni6; 1188 struct mbuf *n = NULL; 1189 u_int16_t qtype; 1190 int subjlen; 1191 int replylen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo); 1192 struct ni_reply_fqdn *fqdn; 1193 int addrs; /* for NI_QTYPE_NODEADDR */ 1194 struct ifnet *ifp = NULL; /* for NI_QTYPE_NODEADDR */ 1195 struct sockaddr_in6 sin6; /* double meaning; ip6_dst and subjectaddr */ 1196 struct ip6_hdr *ip6; 1197 int oldfqdn = 0; /* if 1, return pascal string (03 draft) */ 1198 char *subj = NULL; 1199 1200 ip6 = mtod(m, struct ip6_hdr *); 1201 IP6_EXTHDR_GET(ni6, struct icmp6_nodeinfo *, m, off, sizeof(*ni6)); 1202 if (ni6 == NULL) { 1203 /* m is already reclaimed */ 1204 return NULL; 1205 } 1206 1207 /* 1208 * Validate IPv6 destination address. 1209 * 1210 * The Responder must discard the Query without further processing 1211 * unless it is one of the Responder's unicast or anycast addresses, or 1212 * a link-local scope multicast address which the Responder has joined. 1213 * [icmp-name-lookups-07, Section 4.] 1214 */ 1215 bzero(&sin6, sizeof(sin6)); 1216 sin6.sin6_family = AF_INET6; 1217 sin6.sin6_len = sizeof(struct sockaddr_in6); 1218 bcopy(&ip6->ip6_dst, &sin6.sin6_addr, sizeof(sin6.sin6_addr)); 1219 /* XXX scopeid */ 1220 if (ifa_ifwithaddr((struct sockaddr *)&sin6)) 1221 ; /* unicast/anycast, fine */ 1222 else if (IN6_IS_ADDR_MC_LINKLOCAL(&sin6.sin6_addr)) 1223 ; /* link-local multicast, fine */ 1224 else 1225 goto bad; 1226 1227 /* validate query Subject field. */ 1228 qtype = ntohs(ni6->ni_qtype); 1229 subjlen = m->m_pkthdr.len - off - sizeof(struct icmp6_nodeinfo); 1230 switch (qtype) { 1231 case NI_QTYPE_NOOP: 1232 case NI_QTYPE_SUPTYPES: 1233 /* 07 draft */ 1234 if (ni6->ni_code == ICMP6_NI_SUBJ_FQDN && subjlen == 0) 1235 break; 1236 /* FALLTHROUGH */ 1237 case NI_QTYPE_FQDN: 1238 case NI_QTYPE_NODEADDR: 1239 switch (ni6->ni_code) { 1240 case ICMP6_NI_SUBJ_IPV6: 1241 #if ICMP6_NI_SUBJ_IPV6 != 0 1242 case 0: 1243 #endif 1244 /* 1245 * backward compatibility - try to accept 03 draft 1246 * format, where no Subject is present. 1247 */ 1248 if (qtype == NI_QTYPE_FQDN && ni6->ni_code == 0 && 1249 subjlen == 0) { 1250 oldfqdn++; 1251 break; 1252 } 1253 #if ICMP6_NI_SUBJ_IPV6 != 0 1254 if (ni6->ni_code != ICMP6_NI_SUBJ_IPV6) 1255 goto bad; 1256 #endif 1257 1258 if (subjlen != sizeof(sin6.sin6_addr)) 1259 goto bad; 1260 1261 /* 1262 * Validate Subject address. 1263 * 1264 * Not sure what exactly "address belongs to the node" 1265 * means in the spec, is it just unicast, or what? 1266 * 1267 * At this moment we consider Subject address as 1268 * "belong to the node" if the Subject address equals 1269 * to the IPv6 destination address; validation for 1270 * IPv6 destination address should have done enough 1271 * check for us. 1272 * 1273 * We do not do proxy at this moment. 1274 */ 1275 /* m_pulldown instead of copy? */ 1276 m_copydata(m, off + sizeof(struct icmp6_nodeinfo), 1277 subjlen, (caddr_t)&sin6.sin6_addr); 1278 /* XXX kame scope hack */ 1279 if (IN6_IS_SCOPE_EMBED(&sin6.sin6_addr)) { 1280 if ((m->m_flags & M_PKTHDR) != 0 && 1281 m->m_pkthdr.rcvif) { 1282 sin6.sin6_addr.s6_addr16[1] = 1283 htons(m->m_pkthdr.rcvif->if_index); 1284 } 1285 } 1286 subj = (char *)&sin6; 1287 if (IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, &sin6.sin6_addr)) 1288 break; 1289 1290 /* 1291 * XXX if we are to allow other cases, we should really 1292 * be careful about scope here. 1293 * basically, we should disallow queries toward IPv6 1294 * destination X with subject Y, if scope(X) > scope(Y). 1295 * if we allow scope(X) > scope(Y), it will result in 1296 * information leakage across scope boundary. 1297 */ 1298 goto bad; 1299 1300 case ICMP6_NI_SUBJ_FQDN: 1301 /* 1302 * Validate Subject name with gethostname(3). 1303 * 1304 * The behavior may need some debate, since: 1305 * - we are not sure if the node has FQDN as 1306 * hostname (returned by gethostname(3)). 1307 * - the code does wildcard match for truncated names. 1308 * however, we are not sure if we want to perform 1309 * wildcard match, if gethostname(3) side has 1310 * truncated hostname. 1311 */ 1312 n = ni6_nametodns(hostname, hostnamelen, 0); 1313 if (!n || n->m_next || n->m_len == 0) 1314 goto bad; 1315 IP6_EXTHDR_GET(subj, char *, m, 1316 off + sizeof(struct icmp6_nodeinfo), subjlen); 1317 if (subj == NULL) 1318 goto bad; 1319 if (!ni6_dnsmatch(subj, subjlen, mtod(n, const char *), 1320 n->m_len)) { 1321 goto bad; 1322 } 1323 m_freem(n); 1324 n = NULL; 1325 break; 1326 1327 case ICMP6_NI_SUBJ_IPV4: /* XXX: to be implemented? */ 1328 default: 1329 goto bad; 1330 } 1331 break; 1332 } 1333 1334 /* refuse based on configuration. XXX ICMP6_NI_REFUSED? */ 1335 switch (qtype) { 1336 case NI_QTYPE_FQDN: 1337 if ((icmp6_nodeinfo & 1) == 0) 1338 goto bad; 1339 break; 1340 case NI_QTYPE_NODEADDR: 1341 if ((icmp6_nodeinfo & 2) == 0) 1342 goto bad; 1343 break; 1344 } 1345 1346 /* guess reply length */ 1347 switch (qtype) { 1348 case NI_QTYPE_NOOP: 1349 break; /* no reply data */ 1350 case NI_QTYPE_SUPTYPES: 1351 replylen += sizeof(u_int32_t); 1352 break; 1353 case NI_QTYPE_FQDN: 1354 /* XXX will append an mbuf */ 1355 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1356 break; 1357 case NI_QTYPE_NODEADDR: 1358 addrs = ni6_addrs(ni6, m, &ifp, subj); 1359 if ((replylen += addrs * (sizeof(struct in6_addr) + 1360 sizeof(u_int32_t))) > MCLBYTES) 1361 replylen = MCLBYTES; /* XXX: will truncate pkt later */ 1362 break; 1363 default: 1364 /* 1365 * XXX: We must return a reply with the ICMP6 code 1366 * `unknown Qtype' in this case. However we regard the case 1367 * as an FQDN query for backward compatibility. 1368 * Older versions set a random value to this field, 1369 * so it rarely varies in the defined qtypes. 1370 * But the mechanism is not reliable... 1371 * maybe we should obsolete older versions. 1372 */ 1373 qtype = NI_QTYPE_FQDN; 1374 /* XXX will append an mbuf */ 1375 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1376 oldfqdn++; 1377 break; 1378 } 1379 1380 /* allocate an mbuf to reply. */ 1381 MGETHDR(n, M_DONTWAIT, m->m_type); 1382 if (n == NULL) { 1383 m_freem(m); 1384 return (NULL); 1385 } 1386 M_DUP_PKTHDR(n, m); /* just for rcvif */ 1387 if (replylen > MHLEN) { 1388 if (replylen > MCLBYTES) { 1389 /* 1390 * XXX: should we try to allocate more? But MCLBYTES 1391 * is probably much larger than IPV6_MMTU... 1392 */ 1393 goto bad; 1394 } 1395 MCLGET(n, M_DONTWAIT); 1396 if ((n->m_flags & M_EXT) == 0) { 1397 goto bad; 1398 } 1399 } 1400 n->m_pkthdr.len = n->m_len = replylen; 1401 1402 /* copy mbuf header and IPv6 + Node Information base headers */ 1403 bcopy(mtod(m, caddr_t), mtod(n, caddr_t), sizeof(struct ip6_hdr)); 1404 nni6 = (struct icmp6_nodeinfo *)(mtod(n, struct ip6_hdr *) + 1); 1405 bcopy((caddr_t)ni6, (caddr_t)nni6, sizeof(struct icmp6_nodeinfo)); 1406 1407 /* qtype dependent procedure */ 1408 switch (qtype) { 1409 case NI_QTYPE_NOOP: 1410 nni6->ni_code = ICMP6_NI_SUCCESS; 1411 nni6->ni_flags = 0; 1412 break; 1413 case NI_QTYPE_SUPTYPES: 1414 { 1415 u_int32_t v; 1416 nni6->ni_code = ICMP6_NI_SUCCESS; 1417 nni6->ni_flags = htons(0x0000); /* raw bitmap */ 1418 /* supports NOOP, SUPTYPES, FQDN, and NODEADDR */ 1419 v = (u_int32_t)htonl(0x0000000f); 1420 bcopy(&v, nni6 + 1, sizeof(u_int32_t)); 1421 break; 1422 } 1423 case NI_QTYPE_FQDN: 1424 nni6->ni_code = ICMP6_NI_SUCCESS; 1425 fqdn = (struct ni_reply_fqdn *)(mtod(n, caddr_t) + 1426 sizeof(struct ip6_hdr) + 1427 sizeof(struct icmp6_nodeinfo)); 1428 nni6->ni_flags = 0; /* XXX: meaningless TTL */ 1429 fqdn->ni_fqdn_ttl = 0; /* ditto. */ 1430 /* 1431 * XXX do we really have FQDN in variable "hostname"? 1432 */ 1433 n->m_next = ni6_nametodns(hostname, hostnamelen, oldfqdn); 1434 if (n->m_next == NULL) 1435 goto bad; 1436 /* XXX we assume that n->m_next is not a chain */ 1437 if (n->m_next->m_next != NULL) 1438 goto bad; 1439 n->m_pkthdr.len += n->m_next->m_len; 1440 break; 1441 case NI_QTYPE_NODEADDR: 1442 { 1443 int lenlim, copied; 1444 1445 nni6->ni_code = ICMP6_NI_SUCCESS; 1446 n->m_pkthdr.len = n->m_len = 1447 sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo); 1448 lenlim = M_TRAILINGSPACE(n); 1449 copied = ni6_store_addrs(ni6, nni6, ifp, lenlim); 1450 /* XXX: reset mbuf length */ 1451 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) + 1452 sizeof(struct icmp6_nodeinfo) + copied; 1453 break; 1454 } 1455 default: 1456 break; /* XXX impossible! */ 1457 } 1458 1459 nni6->ni_type = ICMP6_NI_REPLY; 1460 m_freem(m); 1461 return (n); 1462 1463 bad: 1464 m_freem(m); 1465 if (n) 1466 m_freem(n); 1467 return (NULL); 1468 } 1469 #undef hostnamelen 1470 1471 #define isupper(x) ('A' <= (x) && (x) <= 'Z') 1472 #define isalpha(x) (('A' <= (x) && (x) <= 'Z') || ('a' <= (x) && (x) <= 'z')) 1473 #define isalnum(x) (isalpha(x) || ('0' <= (x) && (x) <= '9')) 1474 #define tolower(x) (isupper(x) ? (x) + 'a' - 'A' : (x)) 1475 1476 /* 1477 * make a mbuf with DNS-encoded string. no compression support. 1478 * 1479 * XXX names with less than 2 dots (like "foo" or "foo.section") will be 1480 * treated as truncated name (two \0 at the end). this is a wild guess. 1481 * 1482 * old - return pascal string if non-zero 1483 */ 1484 static struct mbuf * 1485 ni6_nametodns(const char *name, int namelen, int old) 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 (!isalnum(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(const char *a, int alen, const char *b, int blen) 1593 { 1594 const char *a0, *b0; 1595 int l; 1596 1597 /* simplest case - need validation? */ 1598 if (alen == blen && bcmp(a, b, alen) == 0) 1599 return 1; 1600 1601 a0 = a; 1602 b0 = b; 1603 1604 /* termination is mandatory */ 1605 if (alen < 2 || blen < 2) 1606 return 0; 1607 if (a0[alen - 1] != '\0' || b0[blen - 1] != '\0') 1608 return 0; 1609 alen--; 1610 blen--; 1611 1612 while (a - a0 < alen && b - b0 < blen) { 1613 if (a - a0 + 1 > alen || b - b0 + 1 > blen) 1614 return 0; 1615 1616 if ((signed char)a[0] < 0 || (signed char)b[0] < 0) 1617 return 0; 1618 /* we don't support compression yet */ 1619 if (a[0] >= 64 || b[0] >= 64) 1620 return 0; 1621 1622 /* truncated case */ 1623 if (a[0] == 0 && a - a0 == alen - 1) 1624 return 1; 1625 if (b[0] == 0 && b - b0 == blen - 1) 1626 return 1; 1627 if (a[0] == 0 || b[0] == 0) 1628 return 0; 1629 1630 if (a[0] != b[0]) 1631 return 0; 1632 l = a[0]; 1633 if (a - a0 + 1 + l > alen || b - b0 + 1 + l > blen) 1634 return 0; 1635 if (bcmp(a + 1, b + 1, l) != 0) 1636 return 0; 1637 1638 a += 1 + l; 1639 b += 1 + l; 1640 } 1641 1642 if (a - a0 == alen && b - b0 == blen) 1643 return 1; 1644 else 1645 return 0; 1646 } 1647 1648 /* 1649 * calculate the number of addresses to be returned in the node info reply. 1650 */ 1651 static int 1652 ni6_addrs(struct icmp6_nodeinfo *ni6, struct mbuf *m, struct ifnet **ifpp, 1653 char *subj) 1654 { 1655 struct ifnet *ifp; 1656 struct in6_ifaddr *ifa6; 1657 struct ifaddr *ifa; 1658 struct sockaddr_in6 *subj_ip6 = NULL; /* XXX pedant */ 1659 int addrs = 0, addrsofif, iffound = 0; 1660 int niflags = ni6->ni_flags; 1661 1662 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0) { 1663 switch (ni6->ni_code) { 1664 case ICMP6_NI_SUBJ_IPV6: 1665 if (subj == NULL) /* must be impossible... */ 1666 return (0); 1667 subj_ip6 = (struct sockaddr_in6 *)subj; 1668 break; 1669 default: 1670 /* 1671 * XXX: we only support IPv6 subject address for 1672 * this Qtype. 1673 */ 1674 return (0); 1675 } 1676 } 1677 1678 TAILQ_FOREACH(ifp, &ifnet, if_list) { 1679 addrsofif = 0; 1680 TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list) { 1681 if (ifa->ifa_addr->sa_family != AF_INET6) 1682 continue; 1683 ifa6 = (struct in6_ifaddr *)ifa; 1684 1685 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0 && 1686 IN6_ARE_ADDR_EQUAL(&subj_ip6->sin6_addr, 1687 &ifa6->ia_addr.sin6_addr)) 1688 iffound = 1; 1689 1690 /* 1691 * IPv4-mapped addresses can only be returned by a 1692 * Node Information proxy, since they represent 1693 * addresses of IPv4-only nodes, which perforce do 1694 * not implement this protocol. 1695 * [icmp-name-lookups-07, Section 5.4] 1696 * So we don't support NI_NODEADDR_FLAG_COMPAT in 1697 * this function at this moment. 1698 */ 1699 1700 /* What do we have to do about ::1? */ 1701 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1702 case IPV6_ADDR_SCOPE_LINKLOCAL: 1703 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0) 1704 continue; 1705 break; 1706 case IPV6_ADDR_SCOPE_SITELOCAL: 1707 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0) 1708 continue; 1709 break; 1710 case IPV6_ADDR_SCOPE_GLOBAL: 1711 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0) 1712 continue; 1713 break; 1714 default: 1715 continue; 1716 } 1717 1718 /* 1719 * check if anycast is okay. 1720 * XXX: just experimental. not in the spec. 1721 */ 1722 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 && 1723 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0) 1724 continue; /* we need only unicast addresses */ 1725 1726 addrsofif++; /* count the address */ 1727 } 1728 if (iffound) { 1729 *ifpp = ifp; 1730 return (addrsofif); 1731 } 1732 1733 addrs += addrsofif; 1734 } 1735 1736 return (addrs); 1737 } 1738 1739 static int 1740 ni6_store_addrs(struct icmp6_nodeinfo *ni6, struct icmp6_nodeinfo *nni6, 1741 struct ifnet *ifp0, int resid) 1742 { 1743 struct ifnet *ifp = ifp0 ? ifp0 : TAILQ_FIRST(&ifnet); 1744 struct in6_ifaddr *ifa6; 1745 struct ifaddr *ifa; 1746 struct ifnet *ifp_dep = NULL; 1747 int copied = 0, allow_deprecated = 0; 1748 u_char *cp = (u_char *)(nni6 + 1); 1749 int niflags = ni6->ni_flags; 1750 u_int32_t ltime; 1751 1752 if (ifp0 == NULL && !(niflags & NI_NODEADDR_FLAG_ALL)) 1753 return (0); /* needless to copy */ 1754 1755 again: 1756 1757 for (; ifp != TAILQ_END(&ifnet); ifp = TAILQ_NEXT(ifp, if_list)) { 1758 TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list) { 1759 if (ifa->ifa_addr->sa_family != AF_INET6) 1760 continue; 1761 ifa6 = (struct in6_ifaddr *)ifa; 1762 1763 if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) != 0 && 1764 allow_deprecated == 0) { 1765 /* 1766 * prefererred address should be put before 1767 * deprecated addresses. 1768 */ 1769 1770 /* record the interface for later search */ 1771 if (ifp_dep == NULL) 1772 ifp_dep = ifp; 1773 1774 continue; 1775 } 1776 else if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) == 0 && 1777 allow_deprecated != 0) 1778 continue; /* we now collect deprecated addrs */ 1779 1780 /* What do we have to do about ::1? */ 1781 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1782 case IPV6_ADDR_SCOPE_LINKLOCAL: 1783 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0) 1784 continue; 1785 break; 1786 case IPV6_ADDR_SCOPE_SITELOCAL: 1787 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0) 1788 continue; 1789 break; 1790 case IPV6_ADDR_SCOPE_GLOBAL: 1791 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0) 1792 continue; 1793 break; 1794 default: 1795 continue; 1796 } 1797 1798 /* 1799 * check if anycast is okay. 1800 * XXX: just experimental. not in the spec. 1801 */ 1802 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 && 1803 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0) 1804 continue; 1805 1806 /* now we can copy the address */ 1807 if (resid < sizeof(struct in6_addr) + 1808 sizeof(u_int32_t)) { 1809 /* 1810 * We give up much more copy. 1811 * Set the truncate flag and return. 1812 */ 1813 nni6->ni_flags |= 1814 NI_NODEADDR_FLAG_TRUNCATE; 1815 return (copied); 1816 } 1817 1818 /* 1819 * Set the TTL of the address. 1820 * The TTL value should be one of the following 1821 * according to the specification: 1822 * 1823 * 1. The remaining lifetime of a DHCP lease on the 1824 * address, or 1825 * 2. The remaining Valid Lifetime of a prefix from 1826 * which the address was derived through Stateless 1827 * Autoconfiguration. 1828 * 1829 * Note that we currently do not support stateful 1830 * address configuration by DHCPv6, so the former 1831 * case can't happen. 1832 * 1833 * TTL must be 2^31 > TTL >= 0. 1834 */ 1835 if (ifa6->ia6_lifetime.ia6t_expire == 0) 1836 ltime = ND6_INFINITE_LIFETIME; 1837 else { 1838 if (ifa6->ia6_lifetime.ia6t_expire > 1839 time_second) 1840 ltime = htonl(ifa6->ia6_lifetime.ia6t_expire - time_second); 1841 else 1842 ltime = 0; 1843 } 1844 1845 bcopy(<ime, cp, sizeof(u_int32_t)); 1846 cp += sizeof(u_int32_t); 1847 1848 /* copy the address itself */ 1849 bcopy(&ifa6->ia_addr.sin6_addr, cp, 1850 sizeof(struct in6_addr)); 1851 /* XXX: KAME link-local hack; remove ifindex */ 1852 if (IN6_IS_ADDR_LINKLOCAL(&ifa6->ia_addr.sin6_addr)) 1853 ((struct in6_addr *)cp)->s6_addr16[1] = 0; 1854 cp += sizeof(struct in6_addr); 1855 1856 resid -= (sizeof(struct in6_addr) + sizeof(u_int32_t)); 1857 copied += (sizeof(struct in6_addr) + 1858 sizeof(u_int32_t)); 1859 } 1860 if (ifp0) /* we need search only on the specified IF */ 1861 break; 1862 } 1863 1864 if (allow_deprecated == 0 && ifp_dep != NULL) { 1865 ifp = ifp_dep; 1866 allow_deprecated = 1; 1867 1868 goto again; 1869 } 1870 1871 return (copied); 1872 } 1873 1874 /* 1875 * XXX almost dup'ed code with rip6_input. 1876 */ 1877 static int 1878 icmp6_rip6_input(struct mbuf **mp, int off) 1879 { 1880 struct mbuf *m = *mp; 1881 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1882 struct in6pcb *in6p; 1883 struct in6pcb *last = NULL; 1884 struct sockaddr_in6 rip6src; 1885 struct icmp6_hdr *icmp6; 1886 struct mbuf *opts = NULL; 1887 1888 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 1889 if (icmp6 == NULL) { 1890 /* m is already reclaimed */ 1891 return IPPROTO_DONE; 1892 } 1893 1894 bzero(&rip6src, sizeof(rip6src)); 1895 rip6src.sin6_len = sizeof(struct sockaddr_in6); 1896 rip6src.sin6_family = AF_INET6; 1897 /* KAME hack: recover scopeid */ 1898 (void)in6_recoverscope(&rip6src, &ip6->ip6_src, m->m_pkthdr.rcvif); 1899 1900 CIRCLEQ_FOREACH(in6p, &rawin6pcbtable.inpt_queue, inp_queue) { 1901 if (!(in6p->in6p_flags & INP_IPV6)) 1902 continue; 1903 if (in6p->in6p_ip6_nxt != IPPROTO_ICMPV6) 1904 continue; 1905 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr) && 1906 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr, &ip6->ip6_dst)) 1907 continue; 1908 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr) && 1909 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr, &ip6->ip6_src)) 1910 continue; 1911 if (in6p->in6p_icmp6filt 1912 && ICMP6_FILTER_WILLBLOCK(icmp6->icmp6_type, 1913 in6p->in6p_icmp6filt)) 1914 continue; 1915 if (last) { 1916 struct mbuf *n; 1917 if ((n = m_copy(m, 0, (int)M_COPYALL)) != NULL) { 1918 if (last->in6p_flags & IN6P_CONTROLOPTS) 1919 ip6_savecontrol(last, n, &opts); 1920 /* strip intermediate headers */ 1921 m_adj(n, off); 1922 if (sbappendaddr(&last->in6p_socket->so_rcv, 1923 (struct sockaddr *)&rip6src, 1924 n, opts) == 0) { 1925 /* should notify about lost packet */ 1926 m_freem(n); 1927 if (opts) 1928 m_freem(opts); 1929 } else 1930 sorwakeup(last->in6p_socket); 1931 opts = NULL; 1932 } 1933 } 1934 last = in6p; 1935 } 1936 if (last) { 1937 if (last->in6p_flags & IN6P_CONTROLOPTS) 1938 ip6_savecontrol(last, m, &opts); 1939 /* strip intermediate headers */ 1940 m_adj(m, off); 1941 if (sbappendaddr(&last->in6p_socket->so_rcv, 1942 (struct sockaddr *)&rip6src, 1943 m, opts) == 0) { 1944 m_freem(m); 1945 if (opts) 1946 m_freem(opts); 1947 } else 1948 sorwakeup(last->in6p_socket); 1949 } else { 1950 m_freem(m); 1951 ip6stat.ip6s_delivered--; 1952 } 1953 return IPPROTO_DONE; 1954 } 1955 1956 /* 1957 * Reflect the ip6 packet back to the source. 1958 * OFF points to the icmp6 header, counted from the top of the mbuf. 1959 * 1960 * Note: RFC 1885 required that an echo reply should be truncated if it 1961 * did not fit in with (return) path MTU, and KAME code supported the 1962 * behavior. However, as a clarification after the RFC, this limitation 1963 * was removed in a revised version of the spec, RFC 2463. We had kept the 1964 * old behavior, with a (non-default) ifdef block, while the new version of 1965 * the spec was an internet-draft status, and even after the new RFC was 1966 * published. But it would rather make sense to clean the obsoleted part 1967 * up, and to make the code simpler at this stage. 1968 */ 1969 void 1970 icmp6_reflect(struct mbuf *m, size_t off) 1971 { 1972 struct ip6_hdr *ip6; 1973 struct icmp6_hdr *icmp6; 1974 struct in6_ifaddr *ia; 1975 struct in6_addr t, *src = 0; 1976 int plen; 1977 int type, code; 1978 struct ifnet *outif = NULL; 1979 struct sockaddr_in6 sa6_src, sa6_dst; 1980 1981 /* too short to reflect */ 1982 if (off < sizeof(struct ip6_hdr)) { 1983 nd6log((LOG_DEBUG, 1984 "sanity fail: off=%lx, sizeof(ip6)=%lx in %s:%d\n", 1985 (u_long)off, (u_long)sizeof(struct ip6_hdr), 1986 __FILE__, __LINE__)); 1987 goto bad; 1988 } 1989 1990 /* 1991 * If there are extra headers between IPv6 and ICMPv6, strip 1992 * off that header first. 1993 */ 1994 #ifdef DIAGNOSTIC 1995 if (sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) > MHLEN) 1996 panic("assumption failed in icmp6_reflect"); 1997 #endif 1998 if (off > sizeof(struct ip6_hdr)) { 1999 size_t l; 2000 struct ip6_hdr nip6; 2001 2002 l = off - sizeof(struct ip6_hdr); 2003 m_copydata(m, 0, sizeof(nip6), (caddr_t)&nip6); 2004 m_adj(m, l); 2005 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 2006 if (m->m_len < l) { 2007 if ((m = m_pullup(m, l)) == NULL) 2008 return; 2009 } 2010 bcopy((caddr_t)&nip6, mtod(m, caddr_t), sizeof(nip6)); 2011 } else /* off == sizeof(struct ip6_hdr) */ { 2012 size_t l; 2013 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 2014 if (m->m_len < l) { 2015 if ((m = m_pullup(m, l)) == NULL) 2016 return; 2017 } 2018 } 2019 plen = m->m_pkthdr.len - sizeof(struct ip6_hdr); 2020 ip6 = mtod(m, struct ip6_hdr *); 2021 ip6->ip6_nxt = IPPROTO_ICMPV6; 2022 icmp6 = (struct icmp6_hdr *)(ip6 + 1); 2023 type = icmp6->icmp6_type; /* keep type for statistics */ 2024 code = icmp6->icmp6_code; /* ditto. */ 2025 2026 t = ip6->ip6_dst; 2027 /* 2028 * ip6_input() drops a packet if its src is multicast. 2029 * So, the src is never multicast. 2030 */ 2031 ip6->ip6_dst = ip6->ip6_src; 2032 2033 /* 2034 * XXX: make sure to embed scope zone information, using 2035 * already embedded IDs or the received interface (if any). 2036 * Note that rcvif may be NULL. 2037 * TODO: scoped routing case (XXX). 2038 */ 2039 bzero(&sa6_src, sizeof(sa6_src)); 2040 sa6_src.sin6_family = AF_INET6; 2041 sa6_src.sin6_len = sizeof(sa6_src); 2042 sa6_src.sin6_addr = ip6->ip6_dst; 2043 in6_recoverscope(&sa6_src, &ip6->ip6_dst, m->m_pkthdr.rcvif); 2044 in6_embedscope(&ip6->ip6_dst, &sa6_src, NULL, NULL); 2045 bzero(&sa6_dst, sizeof(sa6_dst)); 2046 sa6_dst.sin6_family = AF_INET6; 2047 sa6_dst.sin6_len = sizeof(sa6_dst); 2048 sa6_dst.sin6_addr = t; 2049 in6_recoverscope(&sa6_dst, &t, m->m_pkthdr.rcvif); 2050 in6_embedscope(&t, &sa6_dst, NULL, NULL); 2051 2052 /* 2053 * If the incoming packet was addressed directly to us (i.e. unicast), 2054 * use dst as the src for the reply. 2055 * The IN6_IFF_NOTREADY case would be VERY rare, but is possible 2056 * (for example) when we encounter an error while forwarding procedure 2057 * destined to a duplicated address of ours. 2058 */ 2059 for (ia = in6_ifaddr; ia; ia = ia->ia_next) 2060 if (IN6_ARE_ADDR_EQUAL(&t, &ia->ia_addr.sin6_addr) && 2061 (ia->ia6_flags & (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY)) == 0) { 2062 src = &t; 2063 break; 2064 } 2065 if (ia == NULL && IN6_IS_ADDR_LINKLOCAL(&t) && (m->m_flags & M_LOOP)) { 2066 /* 2067 * This is the case if the dst is our link-local address 2068 * and the sender is also ourselves. 2069 */ 2070 src = &t; 2071 } 2072 2073 if (src == 0) { 2074 int e; 2075 struct route_in6 ro; 2076 2077 /* 2078 * This case matches to multicasts, our anycast, or unicasts 2079 * that we do not own. Select a source address based on the 2080 * source address of the erroneous packet. 2081 */ 2082 bzero(&ro, sizeof(ro)); 2083 src = in6_selectsrc(&sa6_src, NULL, NULL, &ro, NULL, &e); 2084 if (ro.ro_rt) { /* XXX: see comments in icmp6_mtudisc_update */ 2085 RTFREE(ro.ro_rt); /* XXX: we could use this */ 2086 } 2087 if (src == NULL) { 2088 nd6log((LOG_DEBUG, 2089 "icmp6_reflect: source can't be determined: " 2090 "dst=%s, error=%d\n", 2091 ip6_sprintf(&sa6_src.sin6_addr), e)); 2092 goto bad; 2093 } 2094 } 2095 2096 ip6->ip6_src = *src; 2097 2098 ip6->ip6_flow = 0; 2099 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2100 ip6->ip6_vfc |= IPV6_VERSION; 2101 ip6->ip6_nxt = IPPROTO_ICMPV6; 2102 if (m->m_pkthdr.rcvif) { 2103 /* XXX: This may not be the outgoing interface */ 2104 ip6->ip6_hlim = ND_IFINFO(m->m_pkthdr.rcvif)->chlim; 2105 } else 2106 ip6->ip6_hlim = ip6_defhlim; 2107 2108 icmp6->icmp6_cksum = 0; 2109 icmp6->icmp6_cksum = in6_cksum(m, IPPROTO_ICMPV6, 2110 sizeof(struct ip6_hdr), plen); 2111 2112 /* 2113 * XXX option handling 2114 */ 2115 2116 m->m_flags &= ~(M_BCAST|M_MCAST); 2117 2118 /* 2119 * To avoid a "too big" situation at an intermediate router 2120 * and the path MTU discovery process, specify the IPV6_MINMTU flag. 2121 * Note that only echo and node information replies are affected, 2122 * since the length of ICMP6 errors is limited to the minimum MTU. 2123 */ 2124 #if NPF > 0 2125 pf_pkt_addr_changed(m); 2126 #endif 2127 if (ip6_output(m, NULL, NULL, IPV6_MINMTU, NULL, &outif, NULL) != 0 && 2128 outif) 2129 icmp6_ifstat_inc(outif, ifs6_out_error); 2130 2131 if (outif) 2132 icmp6_ifoutstat_inc(outif, type, code); 2133 2134 return; 2135 2136 bad: 2137 m_freem(m); 2138 return; 2139 } 2140 2141 void 2142 icmp6_fasttimo() 2143 { 2144 2145 mld6_fasttimeo(); 2146 } 2147 2148 static const char * 2149 icmp6_redirect_diag(struct in6_addr *src6, struct in6_addr *dst6, 2150 struct in6_addr *tgt6) 2151 { 2152 static char buf[1024]; 2153 snprintf(buf, sizeof(buf), "(src=%s dst=%s tgt=%s)", 2154 ip6_sprintf(src6), ip6_sprintf(dst6), ip6_sprintf(tgt6)); 2155 return buf; 2156 } 2157 2158 void 2159 icmp6_redirect_input(struct mbuf *m, int off) 2160 { 2161 struct ifnet *ifp = m->m_pkthdr.rcvif; 2162 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 2163 struct nd_redirect *nd_rd; 2164 int icmp6len = ntohs(ip6->ip6_plen); 2165 char *lladdr = NULL; 2166 int lladdrlen = 0; 2167 struct rtentry *rt = NULL; 2168 int is_router; 2169 int is_onlink; 2170 struct in6_addr src6 = ip6->ip6_src; 2171 struct in6_addr redtgt6; 2172 struct in6_addr reddst6; 2173 union nd_opts ndopts; 2174 2175 if (!ifp) 2176 return; 2177 2178 /* XXX if we are router, we don't update route by icmp6 redirect */ 2179 if (ip6_forwarding) 2180 goto freeit; 2181 if (!icmp6_rediraccept) 2182 goto freeit; 2183 2184 IP6_EXTHDR_GET(nd_rd, struct nd_redirect *, m, off, icmp6len); 2185 if (nd_rd == NULL) { 2186 icmp6stat.icp6s_tooshort++; 2187 return; 2188 } 2189 redtgt6 = nd_rd->nd_rd_target; 2190 reddst6 = nd_rd->nd_rd_dst; 2191 2192 if (IN6_IS_ADDR_LINKLOCAL(&redtgt6)) 2193 redtgt6.s6_addr16[1] = htons(ifp->if_index); 2194 if (IN6_IS_ADDR_LINKLOCAL(&reddst6)) 2195 reddst6.s6_addr16[1] = htons(ifp->if_index); 2196 2197 /* validation */ 2198 if (!IN6_IS_ADDR_LINKLOCAL(&src6)) { 2199 nd6log((LOG_ERR, 2200 "ICMP6 redirect sent from %s rejected; " 2201 "must be from linklocal\n", ip6_sprintf(&src6))); 2202 goto bad; 2203 } 2204 if (ip6->ip6_hlim != 255) { 2205 nd6log((LOG_ERR, 2206 "ICMP6 redirect sent from %s rejected; " 2207 "hlim=%d (must be 255)\n", 2208 ip6_sprintf(&src6), ip6->ip6_hlim)); 2209 goto bad; 2210 } 2211 { 2212 /* ip6->ip6_src must be equal to gw for icmp6->icmp6_reddst */ 2213 struct sockaddr_in6 sin6; 2214 struct in6_addr *gw6; 2215 2216 bzero(&sin6, sizeof(sin6)); 2217 sin6.sin6_family = AF_INET6; 2218 sin6.sin6_len = sizeof(struct sockaddr_in6); 2219 bcopy(&reddst6, &sin6.sin6_addr, sizeof(reddst6)); 2220 rt = rtalloc1((struct sockaddr *)&sin6, 0, 0); 2221 if (rt) { 2222 if (rt->rt_gateway == NULL || 2223 rt->rt_gateway->sa_family != AF_INET6) { 2224 nd6log((LOG_ERR, 2225 "ICMP6 redirect rejected; no route " 2226 "with inet6 gateway found for redirect dst: %s\n", 2227 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2228 RTFREE(rt); 2229 goto bad; 2230 } 2231 2232 gw6 = &(((struct sockaddr_in6 *)rt->rt_gateway)->sin6_addr); 2233 if (bcmp(&src6, gw6, sizeof(struct in6_addr)) != 0) { 2234 nd6log((LOG_ERR, 2235 "ICMP6 redirect rejected; " 2236 "not equal to gw-for-src=%s (must be same): " 2237 "%s\n", 2238 ip6_sprintf(gw6), 2239 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2240 RTFREE(rt); 2241 goto bad; 2242 } 2243 } else { 2244 nd6log((LOG_ERR, 2245 "ICMP6 redirect rejected; " 2246 "no route found for redirect dst: %s\n", 2247 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2248 goto bad; 2249 } 2250 RTFREE(rt); 2251 rt = NULL; 2252 } 2253 if (IN6_IS_ADDR_MULTICAST(&reddst6)) { 2254 nd6log((LOG_ERR, 2255 "ICMP6 redirect rejected; " 2256 "redirect dst must be unicast: %s\n", 2257 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2258 goto bad; 2259 } 2260 2261 is_router = is_onlink = 0; 2262 if (IN6_IS_ADDR_LINKLOCAL(&redtgt6)) 2263 is_router = 1; /* router case */ 2264 if (bcmp(&redtgt6, &reddst6, sizeof(redtgt6)) == 0) 2265 is_onlink = 1; /* on-link destination case */ 2266 if (!is_router && !is_onlink) { 2267 nd6log((LOG_ERR, 2268 "ICMP6 redirect rejected; " 2269 "neither router case nor onlink case: %s\n", 2270 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2271 goto bad; 2272 } 2273 /* validation passed */ 2274 2275 icmp6len -= sizeof(*nd_rd); 2276 nd6_option_init(nd_rd + 1, icmp6len, &ndopts); 2277 if (nd6_options(&ndopts) < 0) { 2278 nd6log((LOG_INFO, "icmp6_redirect_input: " 2279 "invalid ND option, rejected: %s\n", 2280 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2281 /* nd6_options have incremented stats */ 2282 goto freeit; 2283 } 2284 2285 if (ndopts.nd_opts_tgt_lladdr) { 2286 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 2287 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 2288 } 2289 2290 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 2291 nd6log((LOG_INFO, 2292 "icmp6_redirect_input: lladdrlen mismatch for %s " 2293 "(if %d, icmp6 packet %d): %s\n", 2294 ip6_sprintf(&redtgt6), ifp->if_addrlen, lladdrlen - 2, 2295 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2296 goto bad; 2297 } 2298 2299 /* RFC 2461 8.3 */ 2300 nd6_cache_lladdr(ifp, &redtgt6, lladdr, lladdrlen, ND_REDIRECT, 2301 is_onlink ? ND_REDIRECT_ONLINK : ND_REDIRECT_ROUTER); 2302 2303 if (!is_onlink) { /* better router case. perform rtredirect. */ 2304 /* perform rtredirect */ 2305 struct sockaddr_in6 sdst; 2306 struct sockaddr_in6 sgw; 2307 struct sockaddr_in6 ssrc; 2308 unsigned long rtcount; 2309 struct rtentry *newrt = NULL; 2310 2311 /* 2312 * do not install redirect route, if the number of entries 2313 * is too much (> hiwat). note that, the node (= host) will 2314 * work just fine even if we do not install redirect route 2315 * (there will be additional hops, though). 2316 */ 2317 rtcount = rt_timer_count(icmp6_redirect_timeout_q); 2318 if (0 <= ip6_maxdynroutes && rtcount >= ip6_maxdynroutes) 2319 goto freeit; 2320 else if (0 <= icmp6_redirect_lowat && 2321 rtcount > icmp6_redirect_lowat) { 2322 /* 2323 * XXX nuke a victim, install the new one. 2324 */ 2325 } 2326 2327 bzero(&sdst, sizeof(sdst)); 2328 bzero(&sgw, sizeof(sgw)); 2329 bzero(&ssrc, sizeof(ssrc)); 2330 sdst.sin6_family = sgw.sin6_family = ssrc.sin6_family = AF_INET6; 2331 sdst.sin6_len = sgw.sin6_len = ssrc.sin6_len = 2332 sizeof(struct sockaddr_in6); 2333 bcopy(&redtgt6, &sgw.sin6_addr, sizeof(struct in6_addr)); 2334 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2335 bcopy(&src6, &ssrc.sin6_addr, sizeof(struct in6_addr)); 2336 rtredirect((struct sockaddr *)&sdst, (struct sockaddr *)&sgw, 2337 (struct sockaddr *)NULL, RTF_GATEWAY | RTF_HOST, 2338 (struct sockaddr *)&ssrc, 2339 &newrt); 2340 2341 if (newrt) { 2342 (void)rt_timer_add(newrt, icmp6_redirect_timeout, 2343 icmp6_redirect_timeout_q); 2344 rtfree(newrt); 2345 } 2346 } 2347 /* finally update cached route in each socket via pfctlinput */ 2348 { 2349 struct sockaddr_in6 sdst; 2350 2351 bzero(&sdst, sizeof(sdst)); 2352 sdst.sin6_family = AF_INET6; 2353 sdst.sin6_len = sizeof(struct sockaddr_in6); 2354 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2355 pfctlinput(PRC_REDIRECT_HOST, (struct sockaddr *)&sdst); 2356 } 2357 2358 freeit: 2359 m_freem(m); 2360 return; 2361 2362 bad: 2363 icmp6stat.icp6s_badredirect++; 2364 m_freem(m); 2365 } 2366 2367 void 2368 icmp6_redirect_output(struct mbuf *m0, struct rtentry *rt) 2369 { 2370 struct ifnet *ifp; /* my outgoing interface */ 2371 struct in6_addr *ifp_ll6; 2372 struct in6_addr *nexthop; 2373 struct ip6_hdr *sip6; /* m0 as struct ip6_hdr */ 2374 struct mbuf *m = NULL; /* newly allocated one */ 2375 struct ip6_hdr *ip6; /* m as struct ip6_hdr */ 2376 struct nd_redirect *nd_rd; 2377 size_t maxlen; 2378 u_char *p; 2379 struct sockaddr_in6 src_sa; 2380 2381 icmp6_errcount(&icmp6stat.icp6s_outerrhist, ND_REDIRECT, 0); 2382 2383 /* if we are not router, we don't send icmp6 redirect */ 2384 if (!ip6_forwarding) 2385 goto fail; 2386 2387 /* sanity check */ 2388 if (!m0 || !rt || !(rt->rt_flags & RTF_UP) || !(ifp = rt->rt_ifp)) 2389 goto fail; 2390 2391 /* 2392 * Address check: 2393 * the source address must identify a neighbor, and 2394 * the destination address must not be a multicast address 2395 * [RFC 2461, sec 8.2] 2396 */ 2397 sip6 = mtod(m0, struct ip6_hdr *); 2398 bzero(&src_sa, sizeof(src_sa)); 2399 src_sa.sin6_family = AF_INET6; 2400 src_sa.sin6_len = sizeof(src_sa); 2401 src_sa.sin6_addr = sip6->ip6_src; 2402 /* we don't currently use sin6_scope_id, but eventually use it */ 2403 src_sa.sin6_scope_id = in6_addr2scopeid(ifp, &sip6->ip6_src); 2404 if (nd6_is_addr_neighbor(&src_sa, ifp) == 0) 2405 goto fail; 2406 if (IN6_IS_ADDR_MULTICAST(&sip6->ip6_dst)) 2407 goto fail; /* what should we do here? */ 2408 2409 /* rate limit */ 2410 if (icmp6_ratelimit(&sip6->ip6_src, ND_REDIRECT, 0)) 2411 goto fail; 2412 2413 /* 2414 * Since we are going to append up to 1280 bytes (= IPV6_MMTU), 2415 * we almost always ask for an mbuf cluster for simplicity. 2416 * (MHLEN < IPV6_MMTU is almost always true) 2417 */ 2418 #if IPV6_MMTU >= MCLBYTES 2419 # error assumption failed about IPV6_MMTU and MCLBYTES 2420 #endif 2421 MGETHDR(m, M_DONTWAIT, MT_HEADER); 2422 if (m && IPV6_MMTU >= MHLEN) 2423 MCLGET(m, M_DONTWAIT); 2424 if (!m) 2425 goto fail; 2426 m->m_pkthdr.rcvif = NULL; 2427 m->m_len = 0; 2428 maxlen = M_TRAILINGSPACE(m); 2429 maxlen = min(IPV6_MMTU, maxlen); 2430 /* just for safety */ 2431 if (maxlen < sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) + 2432 ((sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7)) { 2433 goto fail; 2434 } 2435 2436 { 2437 /* get ip6 linklocal address for ifp(my outgoing interface). */ 2438 struct in6_ifaddr *ia; 2439 if ((ia = in6ifa_ifpforlinklocal(ifp, 2440 IN6_IFF_NOTREADY| 2441 IN6_IFF_ANYCAST)) == NULL) 2442 goto fail; 2443 ifp_ll6 = &ia->ia_addr.sin6_addr; 2444 } 2445 2446 /* get ip6 linklocal address for the router. */ 2447 if (rt->rt_gateway && (rt->rt_flags & RTF_GATEWAY)) { 2448 struct sockaddr_in6 *sin6; 2449 sin6 = (struct sockaddr_in6 *)rt->rt_gateway; 2450 nexthop = &sin6->sin6_addr; 2451 if (!IN6_IS_ADDR_LINKLOCAL(nexthop)) 2452 nexthop = NULL; 2453 } else 2454 nexthop = NULL; 2455 2456 /* ip6 */ 2457 ip6 = mtod(m, struct ip6_hdr *); 2458 ip6->ip6_flow = 0; 2459 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2460 ip6->ip6_vfc |= IPV6_VERSION; 2461 /* ip6->ip6_plen will be set later */ 2462 ip6->ip6_nxt = IPPROTO_ICMPV6; 2463 ip6->ip6_hlim = 255; 2464 /* ip6->ip6_src must be linklocal addr for my outgoing if. */ 2465 bcopy(ifp_ll6, &ip6->ip6_src, sizeof(struct in6_addr)); 2466 bcopy(&sip6->ip6_src, &ip6->ip6_dst, sizeof(struct in6_addr)); 2467 2468 /* ND Redirect */ 2469 nd_rd = (struct nd_redirect *)(ip6 + 1); 2470 nd_rd->nd_rd_type = ND_REDIRECT; 2471 nd_rd->nd_rd_code = 0; 2472 nd_rd->nd_rd_reserved = 0; 2473 if (rt->rt_flags & RTF_GATEWAY) { 2474 /* 2475 * nd_rd->nd_rd_target must be a link-local address in 2476 * better router cases. 2477 */ 2478 if (!nexthop) 2479 goto fail; 2480 bcopy(nexthop, &nd_rd->nd_rd_target, 2481 sizeof(nd_rd->nd_rd_target)); 2482 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2483 sizeof(nd_rd->nd_rd_dst)); 2484 } else { 2485 /* make sure redtgt == reddst */ 2486 nexthop = &sip6->ip6_dst; 2487 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_target, 2488 sizeof(nd_rd->nd_rd_target)); 2489 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2490 sizeof(nd_rd->nd_rd_dst)); 2491 } 2492 2493 p = (u_char *)(nd_rd + 1); 2494 2495 { 2496 /* target lladdr option */ 2497 struct rtentry *rt_nexthop = NULL; 2498 int len; 2499 struct sockaddr_dl *sdl; 2500 struct nd_opt_hdr *nd_opt; 2501 char *lladdr; 2502 2503 rt_nexthop = nd6_lookup(nexthop, 0, ifp); 2504 if (!rt_nexthop) 2505 goto nolladdropt; 2506 len = sizeof(*nd_opt) + ifp->if_addrlen; 2507 len = (len + 7) & ~7; /* round by 8 */ 2508 /* safety check */ 2509 if (len + (p - (u_char *)ip6) > maxlen) 2510 goto nolladdropt; 2511 if (!(rt_nexthop->rt_flags & RTF_GATEWAY) && 2512 (rt_nexthop->rt_flags & RTF_LLINFO) && 2513 (rt_nexthop->rt_gateway->sa_family == AF_LINK) && 2514 (sdl = (struct sockaddr_dl *)rt_nexthop->rt_gateway) && 2515 sdl->sdl_alen) { 2516 nd_opt = (struct nd_opt_hdr *)p; 2517 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 2518 nd_opt->nd_opt_len = len >> 3; 2519 lladdr = (char *)(nd_opt + 1); 2520 bcopy(LLADDR(sdl), lladdr, ifp->if_addrlen); 2521 p += len; 2522 } 2523 } 2524 nolladdropt:; 2525 2526 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2527 2528 /* just to be safe */ 2529 if (p - (u_char *)ip6 > maxlen) 2530 goto noredhdropt; 2531 2532 { 2533 /* redirected header option */ 2534 int len; 2535 struct nd_opt_rd_hdr *nd_opt_rh; 2536 2537 /* 2538 * compute the maximum size for icmp6 redirect header option. 2539 * XXX room for auth header? 2540 */ 2541 len = maxlen - (p - (u_char *)ip6); 2542 len &= ~7; 2543 2544 /* 2545 * Redirected header option spec (RFC2461 4.6.3) talks nothing 2546 * about padding/truncate rule for the original IP packet. 2547 * From the discussion on IPv6imp in Feb 1999, 2548 * the consensus was: 2549 * - "attach as much as possible" is the goal 2550 * - pad if not aligned (original size can be guessed by 2551 * original ip6 header) 2552 * Following code adds the padding if it is simple enough, 2553 * and truncates if not. 2554 */ 2555 if (len - sizeof(*nd_opt_rh) < m0->m_pkthdr.len) { 2556 /* not enough room, truncate */ 2557 m_adj(m0, (len - sizeof(*nd_opt_rh)) - 2558 m0->m_pkthdr.len); 2559 } else { 2560 /* 2561 * enough room, truncate if not aligned. 2562 * we don't pad here for simplicity. 2563 */ 2564 size_t extra; 2565 2566 extra = m0->m_pkthdr.len % 8; 2567 if (extra) { 2568 /* truncate */ 2569 m_adj(m0, -extra); 2570 } 2571 len = m0->m_pkthdr.len + sizeof(*nd_opt_rh); 2572 } 2573 2574 nd_opt_rh = (struct nd_opt_rd_hdr *)p; 2575 bzero(nd_opt_rh, sizeof(*nd_opt_rh)); 2576 nd_opt_rh->nd_opt_rh_type = ND_OPT_REDIRECTED_HEADER; 2577 nd_opt_rh->nd_opt_rh_len = len >> 3; 2578 p += sizeof(*nd_opt_rh); 2579 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2580 2581 /* connect m0 to m */ 2582 m->m_pkthdr.len += m0->m_pkthdr.len; 2583 m_cat(m, m0); 2584 m0 = NULL; 2585 } 2586 noredhdropt: 2587 if (m0) { 2588 m_freem(m0); 2589 m0 = NULL; 2590 } 2591 2592 sip6 = mtod(m, struct ip6_hdr *); 2593 if (IN6_IS_ADDR_LINKLOCAL(&sip6->ip6_src)) 2594 sip6->ip6_src.s6_addr16[1] = 0; 2595 if (IN6_IS_ADDR_LINKLOCAL(&sip6->ip6_dst)) 2596 sip6->ip6_dst.s6_addr16[1] = 0; 2597 #if 0 2598 if (IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_src)) 2599 ip6->ip6_src.s6_addr16[1] = 0; 2600 if (IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_dst)) 2601 ip6->ip6_dst.s6_addr16[1] = 0; 2602 #endif 2603 if (IN6_IS_ADDR_LINKLOCAL(&nd_rd->nd_rd_target)) 2604 nd_rd->nd_rd_target.s6_addr16[1] = 0; 2605 if (IN6_IS_ADDR_LINKLOCAL(&nd_rd->nd_rd_dst)) 2606 nd_rd->nd_rd_dst.s6_addr16[1] = 0; 2607 2608 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr)); 2609 2610 nd_rd->nd_rd_cksum = 0; 2611 nd_rd->nd_rd_cksum 2612 = in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), ntohs(ip6->ip6_plen)); 2613 2614 /* send the packet to outside... */ 2615 if (ip6_output(m, NULL, NULL, 0, NULL, NULL, NULL) != 0) 2616 icmp6_ifstat_inc(ifp, ifs6_out_error); 2617 2618 icmp6_ifstat_inc(ifp, ifs6_out_msg); 2619 icmp6_ifstat_inc(ifp, ifs6_out_redirect); 2620 icmp6stat.icp6s_outhist[ND_REDIRECT]++; 2621 2622 return; 2623 2624 fail: 2625 if (m) 2626 m_freem(m); 2627 if (m0) 2628 m_freem(m0); 2629 } 2630 2631 /* NRL PCB */ 2632 #define sotoin6pcb sotoinpcb 2633 #define in6pcb inpcb 2634 #define in6p_icmp6filt inp_icmp6filt 2635 2636 /* 2637 * ICMPv6 socket option processing. 2638 */ 2639 int 2640 icmp6_ctloutput(int op, struct socket *so, int level, int optname, 2641 struct mbuf **mp) 2642 { 2643 int error = 0; 2644 int optlen; 2645 struct in6pcb *in6p = sotoin6pcb(so); 2646 struct mbuf *m = *mp; 2647 2648 optlen = m ? m->m_len : 0; 2649 2650 if (level != IPPROTO_ICMPV6) { 2651 if (op == PRCO_SETOPT && m) 2652 (void)m_free(m); 2653 return EINVAL; 2654 } 2655 2656 switch (op) { 2657 case PRCO_SETOPT: 2658 switch (optname) { 2659 case ICMP6_FILTER: 2660 { 2661 struct icmp6_filter *p; 2662 2663 if (optlen != sizeof(*p)) { 2664 error = EMSGSIZE; 2665 break; 2666 } 2667 p = mtod(m, struct icmp6_filter *); 2668 if (!p || !in6p->in6p_icmp6filt) { 2669 error = EINVAL; 2670 break; 2671 } 2672 bcopy(p, in6p->in6p_icmp6filt, 2673 sizeof(struct icmp6_filter)); 2674 error = 0; 2675 break; 2676 } 2677 2678 default: 2679 error = ENOPROTOOPT; 2680 break; 2681 } 2682 if (m) 2683 (void)m_freem(m); 2684 break; 2685 2686 case PRCO_GETOPT: 2687 switch (optname) { 2688 case ICMP6_FILTER: 2689 { 2690 struct icmp6_filter *p; 2691 2692 if (!in6p->in6p_icmp6filt) { 2693 error = EINVAL; 2694 break; 2695 } 2696 *mp = m = m_get(M_WAIT, MT_SOOPTS); 2697 m->m_len = sizeof(struct icmp6_filter); 2698 p = mtod(m, struct icmp6_filter *); 2699 bcopy(in6p->in6p_icmp6filt, p, 2700 sizeof(struct icmp6_filter)); 2701 error = 0; 2702 break; 2703 } 2704 2705 default: 2706 error = ENOPROTOOPT; 2707 break; 2708 } 2709 break; 2710 } 2711 2712 return (error); 2713 } 2714 2715 /* NRL PCB */ 2716 #undef sotoin6pcb 2717 #undef in6pcb 2718 #undef in6p_icmp6filt 2719 2720 /* 2721 * Perform rate limit check. 2722 * Returns 0 if it is okay to send the icmp6 packet. 2723 * Returns 1 if the router SHOULD NOT send this icmp6 packet due to rate 2724 * limitation. 2725 * 2726 * XXX per-destination/type check necessary? 2727 * 2728 * dst - not used at this moment 2729 * type - not used at this moment 2730 * code - not used at this moment 2731 */ 2732 static int 2733 icmp6_ratelimit(const struct in6_addr *dst, const int type, const int code) 2734 { 2735 int ret; 2736 2737 ret = 0; /* okay to send */ 2738 2739 /* PPS limit */ 2740 if (!ppsratecheck(&icmp6errppslim_last, &icmp6errpps_count, 2741 icmp6errppslim)) { 2742 /* The packet is subject to rate limit */ 2743 ret++; 2744 } 2745 2746 return ret; 2747 } 2748 2749 static struct rtentry * 2750 icmp6_mtudisc_clone(struct sockaddr *dst) 2751 { 2752 struct rtentry *rt; 2753 int error; 2754 2755 rt = rtalloc1(dst, 1, 0); 2756 if (rt == 0) 2757 return NULL; 2758 2759 /* If we didn't get a host route, allocate one */ 2760 if ((rt->rt_flags & RTF_HOST) == 0) { 2761 struct rt_addrinfo info; 2762 struct rtentry *nrt; 2763 2764 bzero(&info, sizeof(info)); 2765 info.rti_flags = RTF_GATEWAY | RTF_HOST | RTF_DYNAMIC; 2766 info.rti_info[RTAX_DST] = dst; 2767 info.rti_info[RTAX_GATEWAY] = rt->rt_gateway; 2768 error = rtrequest1(RTM_ADD, &info, rt->rt_priority, &nrt, 0); 2769 if (error) { 2770 rtfree(rt); 2771 return NULL; 2772 } 2773 nrt->rt_rmx = rt->rt_rmx; 2774 rtfree(rt); 2775 rt = nrt; 2776 } 2777 error = rt_timer_add(rt, icmp6_mtudisc_timeout, 2778 icmp6_mtudisc_timeout_q); 2779 if (error) { 2780 rtfree(rt); 2781 return NULL; 2782 } 2783 2784 return rt; /* caller need to call rtfree() */ 2785 } 2786 2787 static void 2788 icmp6_mtudisc_timeout(struct rtentry *rt, struct rttimer *r) 2789 { 2790 if (rt == NULL) 2791 panic("icmp6_mtudisc_timeout: bad route to timeout"); 2792 if ((rt->rt_flags & (RTF_DYNAMIC | RTF_HOST)) == 2793 (RTF_DYNAMIC | RTF_HOST)) { 2794 struct rt_addrinfo info; 2795 2796 bzero(&info, sizeof(info)); 2797 info.rti_flags = rt->rt_flags; 2798 info.rti_info[RTAX_DST] = rt_key(rt); 2799 info.rti_info[RTAX_GATEWAY] = rt->rt_gateway; 2800 info.rti_info[RTAX_NETMASK] = rt_mask(rt); 2801 rtrequest1(RTM_DELETE, &info, rt->rt_priority, NULL, 0); 2802 } else { 2803 if (!(rt->rt_rmx.rmx_locks & RTV_MTU)) 2804 rt->rt_rmx.rmx_mtu = 0; 2805 } 2806 } 2807 2808 static void 2809 icmp6_redirect_timeout(struct rtentry *rt, struct rttimer *r) 2810 { 2811 if (rt == NULL) 2812 panic("icmp6_redirect_timeout: bad route to timeout"); 2813 if ((rt->rt_flags & (RTF_GATEWAY | RTF_DYNAMIC | RTF_HOST)) == 2814 (RTF_GATEWAY | RTF_DYNAMIC | RTF_HOST)) { 2815 struct rt_addrinfo info; 2816 2817 bzero(&info, sizeof(info)); 2818 info.rti_flags = rt->rt_flags; 2819 info.rti_info[RTAX_DST] = rt_key(rt); 2820 info.rti_info[RTAX_GATEWAY] = rt->rt_gateway; 2821 info.rti_info[RTAX_NETMASK] = rt_mask(rt); 2822 rtrequest1(RTM_DELETE, &info, rt->rt_priority, NULL, 0); 2823 } 2824 } 2825 2826 #include <uvm/uvm_extern.h> 2827 #include <sys/sysctl.h> 2828 2829 int *icmpv6ctl_vars[ICMPV6CTL_MAXID] = ICMPV6CTL_VARS; 2830 2831 int 2832 icmp6_sysctl(int *name, u_int namelen, void *oldp, size_t *oldlenp, 2833 void *newp, size_t newlen) 2834 { 2835 /* All sysctl names at this level are terminal. */ 2836 if (namelen != 1) 2837 return ENOTDIR; 2838 2839 switch (name[0]) { 2840 2841 case ICMPV6CTL_STATS: 2842 return sysctl_rdstruct(oldp, oldlenp, newp, 2843 &icmp6stat, sizeof(icmp6stat)); 2844 case ICMPV6CTL_ND6_DRLIST: 2845 case ICMPV6CTL_ND6_PRLIST: 2846 return nd6_sysctl(name[0], oldp, oldlenp, newp, newlen); 2847 default: 2848 if (name[0] < ICMPV6CTL_MAXID) 2849 return (sysctl_int_arr(icmpv6ctl_vars, name, namelen, 2850 oldp, oldlenp, newp, newlen)); 2851 return ENOPROTOOPT; 2852 } 2853 /* NOTREACHED */ 2854 } 2855