1 /* $FreeBSD$ */ 2 /* $KAME: icmp6.c,v 1.211 2001/04/04 05:56:20 itojun 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 * 4. 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 "opt_inet.h" 65 #include "opt_inet6.h" 66 #include "opt_ipsec.h" 67 68 #include <sys/param.h> 69 #include <sys/domain.h> 70 #include <sys/kernel.h> 71 #include <sys/lock.h> 72 #include <sys/malloc.h> 73 #include <sys/mbuf.h> 74 #include <sys/protosw.h> 75 #include <sys/signalvar.h> 76 #include <sys/socket.h> 77 #include <sys/socketvar.h> 78 #include <sys/sx.h> 79 #include <sys/syslog.h> 80 #include <sys/systm.h> 81 #include <sys/time.h> 82 83 #include <net/if.h> 84 #include <net/if_dl.h> 85 #include <net/if_types.h> 86 #include <net/route.h> 87 88 #include <netinet/in.h> 89 #include <netinet/in_pcb.h> 90 #include <netinet/in_var.h> 91 #include <netinet/ip6.h> 92 #include <netinet/icmp6.h> 93 #include <netinet/tcp_var.h> 94 #include <netinet6/in6_ifattach.h> 95 #include <netinet6/in6_pcb.h> 96 #include <netinet6/ip6protosw.h> 97 #include <netinet6/ip6_var.h> 98 #include <netinet6/scope6_var.h> 99 #include <netinet6/mld6_var.h> 100 #include <netinet6/nd6.h> 101 102 #ifdef IPSEC 103 #include <netinet6/ipsec.h> 104 #include <netkey/key.h> 105 #endif 106 107 #ifdef FAST_IPSEC 108 #include <netipsec/ipsec.h> 109 #include <netipsec/key.h> 110 #endif 111 112 #include <net/net_osdep.h> 113 114 extern struct domain inet6domain; 115 116 struct icmp6stat icmp6stat; 117 118 extern struct inpcbinfo ripcbinfo; 119 extern struct inpcbhead ripcb; 120 extern int icmp6errppslim; 121 static int icmp6errpps_count = 0; 122 static struct timeval icmp6errppslim_last; 123 extern int icmp6_nodeinfo; 124 125 static void icmp6_errcount __P((struct icmp6errstat *, int, int)); 126 static int icmp6_rip6_input __P((struct mbuf **, int)); 127 static int icmp6_ratelimit __P((const struct in6_addr *, const int, const int)); 128 static const char *icmp6_redirect_diag __P((struct in6_addr *, 129 struct in6_addr *, struct in6_addr *)); 130 static struct mbuf *ni6_input __P((struct mbuf *, int)); 131 static struct mbuf *ni6_nametodns __P((const char *, int, int)); 132 static int ni6_dnsmatch __P((const char *, int, const char *, int)); 133 static int ni6_addrs __P((struct icmp6_nodeinfo *, struct mbuf *, 134 struct ifnet **, struct in6_addr *)); 135 static int ni6_store_addrs __P((struct icmp6_nodeinfo *, struct icmp6_nodeinfo *, 136 struct ifnet *, int)); 137 static int icmp6_notify_error __P((struct mbuf **, int, int, int)); 138 139 140 void 141 icmp6_init() 142 { 143 mld6_init(); 144 } 145 146 static void 147 icmp6_errcount(stat, type, code) 148 struct icmp6errstat *stat; 149 int type, code; 150 { 151 switch (type) { 152 case ICMP6_DST_UNREACH: 153 switch (code) { 154 case ICMP6_DST_UNREACH_NOROUTE: 155 stat->icp6errs_dst_unreach_noroute++; 156 return; 157 case ICMP6_DST_UNREACH_ADMIN: 158 stat->icp6errs_dst_unreach_admin++; 159 return; 160 case ICMP6_DST_UNREACH_BEYONDSCOPE: 161 stat->icp6errs_dst_unreach_beyondscope++; 162 return; 163 case ICMP6_DST_UNREACH_ADDR: 164 stat->icp6errs_dst_unreach_addr++; 165 return; 166 case ICMP6_DST_UNREACH_NOPORT: 167 stat->icp6errs_dst_unreach_noport++; 168 return; 169 } 170 break; 171 case ICMP6_PACKET_TOO_BIG: 172 stat->icp6errs_packet_too_big++; 173 return; 174 case ICMP6_TIME_EXCEEDED: 175 switch (code) { 176 case ICMP6_TIME_EXCEED_TRANSIT: 177 stat->icp6errs_time_exceed_transit++; 178 return; 179 case ICMP6_TIME_EXCEED_REASSEMBLY: 180 stat->icp6errs_time_exceed_reassembly++; 181 return; 182 } 183 break; 184 case ICMP6_PARAM_PROB: 185 switch (code) { 186 case ICMP6_PARAMPROB_HEADER: 187 stat->icp6errs_paramprob_header++; 188 return; 189 case ICMP6_PARAMPROB_NEXTHEADER: 190 stat->icp6errs_paramprob_nextheader++; 191 return; 192 case ICMP6_PARAMPROB_OPTION: 193 stat->icp6errs_paramprob_option++; 194 return; 195 } 196 break; 197 case ND_REDIRECT: 198 stat->icp6errs_redirect++; 199 return; 200 } 201 stat->icp6errs_unknown++; 202 } 203 204 /* 205 * A wrapper function for icmp6_error() necessary when the erroneous packet 206 * may not contain enough scope zone information. 207 */ 208 void 209 icmp6_error2(m, type, code, param, ifp) 210 struct mbuf *m; 211 int type, code, param; 212 struct ifnet *ifp; 213 { 214 struct ip6_hdr *ip6; 215 216 if (ifp == NULL) 217 return; 218 219 #ifndef PULLDOWN_TEST 220 IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), ); 221 #else 222 if (m->m_len < sizeof(struct ip6_hdr)) { 223 m = m_pullup(m, sizeof(struct ip6_hdr)); 224 if (m == NULL) 225 return; 226 } 227 #endif 228 229 ip6 = mtod(m, struct ip6_hdr *); 230 231 if (in6_setscope(&ip6->ip6_src, ifp, NULL) != 0) 232 return; 233 if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0) 234 return; 235 236 icmp6_error(m, type, code, param); 237 } 238 239 /* 240 * Generate an error packet of type error in response to bad IP6 packet. 241 */ 242 void 243 icmp6_error(m, type, code, param) 244 struct mbuf *m; 245 int type, code, param; 246 { 247 struct ip6_hdr *oip6, *nip6; 248 struct icmp6_hdr *icmp6; 249 u_int preplen; 250 int off; 251 int nxt; 252 253 icmp6stat.icp6s_error++; 254 255 /* count per-type-code statistics */ 256 icmp6_errcount(&icmp6stat.icp6s_outerrhist, type, code); 257 258 #ifdef M_DECRYPTED /*not openbsd*/ 259 if (m->m_flags & M_DECRYPTED) { 260 icmp6stat.icp6s_canterror++; 261 goto freeit; 262 } 263 #endif 264 265 #ifndef PULLDOWN_TEST 266 IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), ); 267 #else 268 if (m->m_len < sizeof(struct ip6_hdr)) { 269 m = m_pullup(m, sizeof(struct ip6_hdr)); 270 if (m == NULL) 271 return; 272 } 273 #endif 274 oip6 = mtod(m, struct ip6_hdr *); 275 276 /* 277 * If the destination address of the erroneous packet is a multicast 278 * address, or the packet was sent using link-layer multicast, 279 * we should basically suppress sending an error (RFC 2463, Section 280 * 2.4). 281 * We have two exceptions (the item e.2 in that section): 282 * - the Pakcet Too Big message can be sent for path MTU discovery. 283 * - the Parameter Problem Message that can be allowed an icmp6 error 284 * in the option type field. This check has been done in 285 * ip6_unknown_opt(), so we can just check the type and code. 286 */ 287 if ((m->m_flags & (M_BCAST|M_MCAST) || 288 IN6_IS_ADDR_MULTICAST(&oip6->ip6_dst)) && 289 (type != ICMP6_PACKET_TOO_BIG && 290 (type != ICMP6_PARAM_PROB || 291 code != ICMP6_PARAMPROB_OPTION))) 292 goto freeit; 293 294 /* 295 * RFC 2463, 2.4 (e.5): source address check. 296 * XXX: the case of anycast source? 297 */ 298 if (IN6_IS_ADDR_UNSPECIFIED(&oip6->ip6_src) || 299 IN6_IS_ADDR_MULTICAST(&oip6->ip6_src)) 300 goto freeit; 301 302 /* 303 * If we are about to send ICMPv6 against ICMPv6 error/redirect, 304 * don't do it. 305 */ 306 nxt = -1; 307 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); 308 if (off >= 0 && nxt == IPPROTO_ICMPV6) { 309 struct icmp6_hdr *icp; 310 311 #ifndef PULLDOWN_TEST 312 IP6_EXTHDR_CHECK(m, 0, off + sizeof(struct icmp6_hdr), ); 313 icp = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 314 #else 315 IP6_EXTHDR_GET(icp, struct icmp6_hdr *, m, off, 316 sizeof(*icp)); 317 if (icp == NULL) { 318 icmp6stat.icp6s_tooshort++; 319 return; 320 } 321 #endif 322 if (icp->icmp6_type < ICMP6_ECHO_REQUEST || 323 icp->icmp6_type == ND_REDIRECT) { 324 /* 325 * ICMPv6 error 326 * Special case: for redirect (which is 327 * informational) we must not send icmp6 error. 328 */ 329 icmp6stat.icp6s_canterror++; 330 goto freeit; 331 } else { 332 /* ICMPv6 informational - send the error */ 333 } 334 } else { 335 /* non-ICMPv6 - send the error */ 336 } 337 338 oip6 = mtod(m, struct ip6_hdr *); /* adjust pointer */ 339 340 /* Finally, do rate limitation check. */ 341 if (icmp6_ratelimit(&oip6->ip6_src, type, code)) { 342 icmp6stat.icp6s_toofreq++; 343 goto freeit; 344 } 345 346 /* 347 * OK, ICMP6 can be generated. 348 */ 349 350 if (m->m_pkthdr.len >= ICMPV6_PLD_MAXLEN) 351 m_adj(m, ICMPV6_PLD_MAXLEN - m->m_pkthdr.len); 352 353 preplen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 354 M_PREPEND(m, preplen, M_DONTWAIT); 355 if (m && m->m_len < preplen) 356 m = m_pullup(m, preplen); 357 if (m == NULL) { 358 nd6log((LOG_DEBUG, "ENOBUFS in icmp6_error %d\n", __LINE__)); 359 return; 360 } 361 362 nip6 = mtod(m, struct ip6_hdr *); 363 nip6->ip6_src = oip6->ip6_src; 364 nip6->ip6_dst = oip6->ip6_dst; 365 366 in6_clearscope(&oip6->ip6_src); 367 in6_clearscope(&oip6->ip6_dst); 368 369 icmp6 = (struct icmp6_hdr *)(nip6 + 1); 370 icmp6->icmp6_type = type; 371 icmp6->icmp6_code = code; 372 icmp6->icmp6_pptr = htonl((u_int32_t)param); 373 374 /* 375 * icmp6_reflect() is designed to be in the input path. 376 * icmp6_error() can be called from both input and output path, 377 * and if we are in output path rcvif could contain bogus value. 378 * clear m->m_pkthdr.rcvif for safety, we should have enough scope 379 * information in ip header (nip6). 380 */ 381 m->m_pkthdr.rcvif = NULL; 382 383 icmp6stat.icp6s_outhist[type]++; 384 icmp6_reflect(m, sizeof(struct ip6_hdr)); /* header order: IPv6 - ICMPv6 */ 385 386 return; 387 388 freeit: 389 /* 390 * If we can't tell whether or not we can generate ICMP6, free it. 391 */ 392 m_freem(m); 393 } 394 395 /* 396 * Process a received ICMP6 message. 397 */ 398 int 399 icmp6_input(mp, offp, proto) 400 struct mbuf **mp; 401 int *offp, proto; 402 { 403 struct mbuf *m = *mp, *n; 404 struct ip6_hdr *ip6, *nip6; 405 struct icmp6_hdr *icmp6, *nicmp6; 406 int off = *offp; 407 int icmp6len = m->m_pkthdr.len - *offp; 408 int code, sum, noff; 409 410 #ifndef PULLDOWN_TEST 411 IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_hdr), IPPROTO_DONE); 412 /* m might change if M_LOOP. So, call mtod after this */ 413 #endif 414 415 /* 416 * Locate icmp6 structure in mbuf, and check 417 * that not corrupted and of at least minimum length 418 */ 419 420 ip6 = mtod(m, struct ip6_hdr *); 421 if (icmp6len < sizeof(struct icmp6_hdr)) { 422 icmp6stat.icp6s_tooshort++; 423 goto freeit; 424 } 425 426 /* 427 * calculate the checksum 428 */ 429 #ifndef PULLDOWN_TEST 430 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off); 431 #else 432 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 433 if (icmp6 == NULL) { 434 icmp6stat.icp6s_tooshort++; 435 return IPPROTO_DONE; 436 } 437 #endif 438 code = icmp6->icmp6_code; 439 440 if ((sum = in6_cksum(m, IPPROTO_ICMPV6, off, icmp6len)) != 0) { 441 nd6log((LOG_ERR, 442 "ICMP6 checksum error(%d|%x) %s\n", 443 icmp6->icmp6_type, sum, ip6_sprintf(&ip6->ip6_src))); 444 icmp6stat.icp6s_checksum++; 445 goto freeit; 446 } 447 448 if (faithprefix_p != NULL && (*faithprefix_p)(&ip6->ip6_dst)) { 449 /* 450 * Deliver very specific ICMP6 type only. 451 * This is important to deliver TOOBIG. Otherwise PMTUD 452 * will not work. 453 */ 454 switch (icmp6->icmp6_type) { 455 case ICMP6_DST_UNREACH: 456 case ICMP6_PACKET_TOO_BIG: 457 case ICMP6_TIME_EXCEEDED: 458 break; 459 default: 460 goto freeit; 461 } 462 } 463 464 icmp6stat.icp6s_inhist[icmp6->icmp6_type]++; 465 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_msg); 466 if (icmp6->icmp6_type < ICMP6_INFOMSG_MASK) 467 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_error); 468 469 switch (icmp6->icmp6_type) { 470 case ICMP6_DST_UNREACH: 471 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_dstunreach); 472 switch (code) { 473 case ICMP6_DST_UNREACH_NOROUTE: 474 code = PRC_UNREACH_NET; 475 break; 476 case ICMP6_DST_UNREACH_ADMIN: 477 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_adminprohib); 478 code = PRC_UNREACH_PROTOCOL; /* is this a good code? */ 479 break; 480 case ICMP6_DST_UNREACH_ADDR: 481 code = PRC_HOSTDEAD; 482 break; 483 case ICMP6_DST_UNREACH_BEYONDSCOPE: 484 /* I mean "source address was incorrect." */ 485 code = PRC_PARAMPROB; 486 break; 487 case ICMP6_DST_UNREACH_NOPORT: 488 code = PRC_UNREACH_PORT; 489 break; 490 default: 491 goto badcode; 492 } 493 goto deliver; 494 break; 495 496 case ICMP6_PACKET_TOO_BIG: 497 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_pkttoobig); 498 499 /* validation is made in icmp6_mtudisc_update */ 500 501 code = PRC_MSGSIZE; 502 503 /* 504 * Updating the path MTU will be done after examining 505 * intermediate extension headers. 506 */ 507 goto deliver; 508 break; 509 510 case ICMP6_TIME_EXCEEDED: 511 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_timeexceed); 512 switch (code) { 513 case ICMP6_TIME_EXCEED_TRANSIT: 514 case ICMP6_TIME_EXCEED_REASSEMBLY: 515 code += PRC_TIMXCEED_INTRANS; 516 break; 517 default: 518 goto badcode; 519 } 520 goto deliver; 521 break; 522 523 case ICMP6_PARAM_PROB: 524 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_paramprob); 525 switch (code) { 526 case ICMP6_PARAMPROB_NEXTHEADER: 527 code = PRC_UNREACH_PROTOCOL; 528 break; 529 case ICMP6_PARAMPROB_HEADER: 530 case ICMP6_PARAMPROB_OPTION: 531 code = PRC_PARAMPROB; 532 break; 533 default: 534 goto badcode; 535 } 536 goto deliver; 537 break; 538 539 case ICMP6_ECHO_REQUEST: 540 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echo); 541 if (code != 0) 542 goto badcode; 543 if ((n = m_copy(m, 0, M_COPYALL)) == NULL) { 544 /* Give up remote */ 545 break; 546 } 547 if ((n->m_flags & M_EXT) != 0 548 || n->m_len < off + sizeof(struct icmp6_hdr)) { 549 struct mbuf *n0 = n; 550 const int maxlen = sizeof(*nip6) + sizeof(*nicmp6); 551 int n0len; 552 553 MGETHDR(n, M_DONTWAIT, n0->m_type); 554 n0len = n0->m_pkthdr.len; /* save for use below */ 555 if (n) 556 M_MOVE_PKTHDR(n, n0); 557 if (n && maxlen >= MHLEN) { 558 MCLGET(n, M_DONTWAIT); 559 if ((n->m_flags & M_EXT) == 0) { 560 m_free(n); 561 n = NULL; 562 } 563 } 564 if (n == NULL) { 565 /* Give up remote */ 566 m_freem(n0); 567 break; 568 } 569 /* 570 * Copy IPv6 and ICMPv6 only. 571 */ 572 nip6 = mtod(n, struct ip6_hdr *); 573 bcopy(ip6, nip6, sizeof(struct ip6_hdr)); 574 nicmp6 = (struct icmp6_hdr *)(nip6 + 1); 575 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr)); 576 noff = sizeof(struct ip6_hdr); 577 /* new mbuf contains only ipv6+icmpv6 headers */ 578 n->m_len = noff + sizeof(struct icmp6_hdr); 579 /* 580 * Adjust mbuf. ip6_plen will be adjusted in 581 * ip6_output(). 582 */ 583 m_adj(n0, off + sizeof(struct icmp6_hdr)); 584 /* recalculate complete packet size */ 585 n->m_pkthdr.len = n0len + (noff - off); 586 n->m_next = n0; 587 } else { 588 nip6 = mtod(n, struct ip6_hdr *); 589 nicmp6 = (struct icmp6_hdr *)((caddr_t)nip6 + off); 590 noff = off; 591 } 592 nicmp6->icmp6_type = ICMP6_ECHO_REPLY; 593 nicmp6->icmp6_code = 0; 594 if (n) { 595 icmp6stat.icp6s_reflect++; 596 icmp6stat.icp6s_outhist[ICMP6_ECHO_REPLY]++; 597 icmp6_reflect(n, noff); 598 } 599 break; 600 601 case ICMP6_ECHO_REPLY: 602 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echoreply); 603 if (code != 0) 604 goto badcode; 605 break; 606 607 case MLD_LISTENER_QUERY: 608 case MLD_LISTENER_REPORT: 609 if (icmp6len < sizeof(struct mld_hdr)) 610 goto badlen; 611 if (icmp6->icmp6_type == MLD_LISTENER_QUERY) /* XXX: ugly... */ 612 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldquery); 613 else 614 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldreport); 615 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 616 /* give up local */ 617 mld6_input(m, off); 618 m = NULL; 619 goto freeit; 620 } 621 mld6_input(n, off); 622 /* m stays. */ 623 break; 624 625 case MLD_LISTENER_DONE: 626 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mlddone); 627 if (icmp6len < sizeof(struct mld_hdr)) /* necessary? */ 628 goto badlen; 629 break; /* nothing to be done in kernel */ 630 631 case MLD_MTRACE_RESP: 632 case MLD_MTRACE: 633 /* XXX: these two are experimental. not officially defined. */ 634 /* XXX: per-interface statistics? */ 635 break; /* just pass it to applications */ 636 637 case ICMP6_WRUREQUEST: /* ICMP6_FQDN_QUERY */ 638 { 639 enum { WRU, FQDN } mode; 640 641 if (!icmp6_nodeinfo) 642 break; 643 644 if (icmp6len == sizeof(struct icmp6_hdr) + 4) 645 mode = WRU; 646 else if (icmp6len >= sizeof(struct icmp6_nodeinfo)) 647 mode = FQDN; 648 else 649 goto badlen; 650 651 #define hostnamelen strlen(hostname) 652 if (mode == FQDN) { 653 #ifndef PULLDOWN_TEST 654 IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_nodeinfo), 655 IPPROTO_DONE); 656 #endif 657 n = m_copy(m, 0, M_COPYALL); 658 if (n) 659 n = ni6_input(n, off); 660 /* XXX meaningless if n == NULL */ 661 noff = sizeof(struct ip6_hdr); 662 } else { 663 u_char *p; 664 int maxlen, maxhlen; 665 666 if ((icmp6_nodeinfo & 5) != 5) 667 break; 668 669 if (code != 0) 670 goto badcode; 671 maxlen = sizeof(*nip6) + sizeof(*nicmp6) + 4; 672 if (maxlen >= MCLBYTES) { 673 /* Give up remote */ 674 break; 675 } 676 MGETHDR(n, M_DONTWAIT, m->m_type); 677 if (n && maxlen > MHLEN) { 678 MCLGET(n, M_DONTWAIT); 679 if ((n->m_flags & M_EXT) == 0) { 680 m_free(n); 681 n = NULL; 682 } 683 } 684 if (!m_dup_pkthdr(n, m, M_DONTWAIT)) { 685 /* 686 * Previous code did a blind M_COPY_PKTHDR 687 * and said "just for rcvif". If true, then 688 * we could tolerate the dup failing (due to 689 * the deep copy of the tag chain). For now 690 * be conservative and just fail. 691 */ 692 m_free(n); 693 n = NULL; 694 } 695 if (n == NULL) { 696 /* Give up remote */ 697 break; 698 } 699 n->m_pkthdr.rcvif = NULL; 700 n->m_len = 0; 701 maxhlen = M_TRAILINGSPACE(n) - maxlen; 702 if (maxhlen > hostnamelen) 703 maxhlen = hostnamelen; 704 /* 705 * Copy IPv6 and ICMPv6 only. 706 */ 707 nip6 = mtod(n, struct ip6_hdr *); 708 bcopy(ip6, nip6, sizeof(struct ip6_hdr)); 709 nicmp6 = (struct icmp6_hdr *)(nip6 + 1); 710 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr)); 711 p = (u_char *)(nicmp6 + 1); 712 bzero(p, 4); 713 bcopy(hostname, p + 4, maxhlen); /* meaningless TTL */ 714 noff = sizeof(struct ip6_hdr); 715 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) + 716 sizeof(struct icmp6_hdr) + 4 + maxhlen; 717 nicmp6->icmp6_type = ICMP6_WRUREPLY; 718 nicmp6->icmp6_code = 0; 719 } 720 #undef hostnamelen 721 if (n) { 722 icmp6stat.icp6s_reflect++; 723 icmp6stat.icp6s_outhist[ICMP6_WRUREPLY]++; 724 icmp6_reflect(n, noff); 725 } 726 break; 727 } 728 729 case ICMP6_WRUREPLY: 730 if (code != 0) 731 goto badcode; 732 break; 733 734 case ND_ROUTER_SOLICIT: 735 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routersolicit); 736 if (code != 0) 737 goto badcode; 738 if (icmp6len < sizeof(struct nd_router_solicit)) 739 goto badlen; 740 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 741 /* give up local */ 742 nd6_rs_input(m, off, icmp6len); 743 m = NULL; 744 goto freeit; 745 } 746 nd6_rs_input(n, off, icmp6len); 747 /* m stays. */ 748 break; 749 750 case ND_ROUTER_ADVERT: 751 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routeradvert); 752 if (code != 0) 753 goto badcode; 754 if (icmp6len < sizeof(struct nd_router_advert)) 755 goto badlen; 756 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 757 /* give up local */ 758 nd6_ra_input(m, off, icmp6len); 759 m = NULL; 760 goto freeit; 761 } 762 nd6_ra_input(n, off, icmp6len); 763 /* m stays. */ 764 break; 765 766 case ND_NEIGHBOR_SOLICIT: 767 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighborsolicit); 768 if (code != 0) 769 goto badcode; 770 if (icmp6len < sizeof(struct nd_neighbor_solicit)) 771 goto badlen; 772 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 773 /* give up local */ 774 nd6_ns_input(m, off, icmp6len); 775 m = NULL; 776 goto freeit; 777 } 778 nd6_ns_input(n, off, icmp6len); 779 /* m stays. */ 780 break; 781 782 case ND_NEIGHBOR_ADVERT: 783 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighboradvert); 784 if (code != 0) 785 goto badcode; 786 if (icmp6len < sizeof(struct nd_neighbor_advert)) 787 goto badlen; 788 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 789 /* give up local */ 790 nd6_na_input(m, off, icmp6len); 791 m = NULL; 792 goto freeit; 793 } 794 nd6_na_input(n, off, icmp6len); 795 /* m stays. */ 796 break; 797 798 case ND_REDIRECT: 799 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_redirect); 800 if (code != 0) 801 goto badcode; 802 if (icmp6len < sizeof(struct nd_redirect)) 803 goto badlen; 804 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 805 /* give up local */ 806 icmp6_redirect_input(m, off); 807 m = NULL; 808 goto freeit; 809 } 810 icmp6_redirect_input(n, off); 811 /* m stays. */ 812 break; 813 814 case ICMP6_ROUTER_RENUMBERING: 815 if (code != ICMP6_ROUTER_RENUMBERING_COMMAND && 816 code != ICMP6_ROUTER_RENUMBERING_RESULT) 817 goto badcode; 818 if (icmp6len < sizeof(struct icmp6_router_renum)) 819 goto badlen; 820 break; 821 822 default: 823 nd6log((LOG_DEBUG, 824 "icmp6_input: unknown type %d(src=%s, dst=%s, ifid=%d)\n", 825 icmp6->icmp6_type, ip6_sprintf(&ip6->ip6_src), 826 ip6_sprintf(&ip6->ip6_dst), 827 m->m_pkthdr.rcvif ? m->m_pkthdr.rcvif->if_index : 0)); 828 if (icmp6->icmp6_type < ICMP6_ECHO_REQUEST) { 829 /* ICMPv6 error: MUST deliver it by spec... */ 830 code = PRC_NCMDS; 831 /* deliver */ 832 } else { 833 /* ICMPv6 informational: MUST not deliver */ 834 break; 835 } 836 deliver: 837 if (icmp6_notify_error(&m, off, icmp6len, code)) { 838 /* In this case, m should've been freed. */ 839 return (IPPROTO_DONE); 840 } 841 break; 842 843 badcode: 844 icmp6stat.icp6s_badcode++; 845 break; 846 847 badlen: 848 icmp6stat.icp6s_badlen++; 849 break; 850 } 851 852 /* deliver the packet to appropriate sockets */ 853 icmp6_rip6_input(&m, *offp); 854 855 return IPPROTO_DONE; 856 857 freeit: 858 m_freem(m); 859 return IPPROTO_DONE; 860 } 861 862 static int 863 icmp6_notify_error(mp, off, icmp6len, code) 864 struct mbuf **mp; 865 int off, icmp6len, code; 866 { 867 struct mbuf *m = *mp; 868 struct icmp6_hdr *icmp6; 869 struct ip6_hdr *eip6; 870 u_int32_t notifymtu; 871 struct sockaddr_in6 icmp6src, icmp6dst; 872 873 if (icmp6len < sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr)) { 874 icmp6stat.icp6s_tooshort++; 875 goto freeit; 876 } 877 #ifndef PULLDOWN_TEST 878 IP6_EXTHDR_CHECK(m, off, 879 sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr), -1); 880 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 881 #else 882 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, 883 sizeof(*icmp6) + sizeof(struct ip6_hdr)); 884 if (icmp6 == NULL) { 885 icmp6stat.icp6s_tooshort++; 886 return (-1); 887 } 888 #endif 889 eip6 = (struct ip6_hdr *)(icmp6 + 1); 890 891 /* Detect the upper level protocol */ 892 { 893 void (*ctlfunc) __P((int, struct sockaddr *, void *)); 894 u_int8_t nxt = eip6->ip6_nxt; 895 int eoff = off + sizeof(struct icmp6_hdr) + 896 sizeof(struct ip6_hdr); 897 struct ip6ctlparam ip6cp; 898 struct in6_addr *finaldst = NULL; 899 int icmp6type = icmp6->icmp6_type; 900 struct ip6_frag *fh; 901 struct ip6_rthdr *rth; 902 struct ip6_rthdr0 *rth0; 903 int rthlen; 904 905 while (1) { /* XXX: should avoid infinite loop explicitly? */ 906 struct ip6_ext *eh; 907 908 switch (nxt) { 909 case IPPROTO_HOPOPTS: 910 case IPPROTO_DSTOPTS: 911 case IPPROTO_AH: 912 #ifndef PULLDOWN_TEST 913 IP6_EXTHDR_CHECK(m, 0, 914 eoff + sizeof(struct ip6_ext), -1); 915 eh = (struct ip6_ext *)(mtod(m, caddr_t) + eoff); 916 #else 917 IP6_EXTHDR_GET(eh, struct ip6_ext *, m, 918 eoff, sizeof(*eh)); 919 if (eh == NULL) { 920 icmp6stat.icp6s_tooshort++; 921 return (-1); 922 } 923 #endif 924 925 if (nxt == IPPROTO_AH) 926 eoff += (eh->ip6e_len + 2) << 2; 927 else 928 eoff += (eh->ip6e_len + 1) << 3; 929 nxt = eh->ip6e_nxt; 930 break; 931 case IPPROTO_ROUTING: 932 /* 933 * When the erroneous packet contains a 934 * routing header, we should examine the 935 * header to determine the final destination. 936 * Otherwise, we can't properly update 937 * information that depends on the final 938 * destination (e.g. path MTU). 939 */ 940 #ifndef PULLDOWN_TEST 941 IP6_EXTHDR_CHECK(m, 0, eoff + sizeof(*rth), -1); 942 rth = (struct ip6_rthdr *) 943 (mtod(m, caddr_t) + eoff); 944 #else 945 IP6_EXTHDR_GET(rth, struct ip6_rthdr *, m, 946 eoff, sizeof(*rth)); 947 if (rth == NULL) { 948 icmp6stat.icp6s_tooshort++; 949 return (-1); 950 } 951 #endif 952 rthlen = (rth->ip6r_len + 1) << 3; 953 /* 954 * XXX: currently there is no 955 * officially defined type other 956 * than type-0. 957 * Note that if the segment left field 958 * is 0, all intermediate hops must 959 * have been passed. 960 */ 961 if (rth->ip6r_segleft && 962 rth->ip6r_type == IPV6_RTHDR_TYPE_0) { 963 int hops; 964 965 #ifndef PULLDOWN_TEST 966 IP6_EXTHDR_CHECK(m, 0, eoff + rthlen, -1); 967 rth0 = (struct ip6_rthdr0 *) 968 (mtod(m, caddr_t) + eoff); 969 #else 970 IP6_EXTHDR_GET(rth0, 971 struct ip6_rthdr0 *, m, 972 eoff, rthlen); 973 if (rth0 == NULL) { 974 icmp6stat.icp6s_tooshort++; 975 return (-1); 976 } 977 #endif 978 /* just ignore a bogus header */ 979 if ((rth0->ip6r0_len % 2) == 0 && 980 (hops = rth0->ip6r0_len/2)) 981 finaldst = (struct in6_addr *)(rth0 + 1) + (hops - 1); 982 } 983 eoff += rthlen; 984 nxt = rth->ip6r_nxt; 985 break; 986 case IPPROTO_FRAGMENT: 987 #ifndef PULLDOWN_TEST 988 IP6_EXTHDR_CHECK(m, 0, eoff + 989 sizeof(struct ip6_frag), -1); 990 fh = (struct ip6_frag *)(mtod(m, caddr_t) + 991 eoff); 992 #else 993 IP6_EXTHDR_GET(fh, struct ip6_frag *, m, 994 eoff, sizeof(*fh)); 995 if (fh == NULL) { 996 icmp6stat.icp6s_tooshort++; 997 return (-1); 998 } 999 #endif 1000 /* 1001 * Data after a fragment header is meaningless 1002 * unless it is the first fragment, but 1003 * we'll go to the notify label for path MTU 1004 * discovery. 1005 */ 1006 if (fh->ip6f_offlg & IP6F_OFF_MASK) 1007 goto notify; 1008 1009 eoff += sizeof(struct ip6_frag); 1010 nxt = fh->ip6f_nxt; 1011 break; 1012 default: 1013 /* 1014 * This case includes ESP and the No Next 1015 * Header. In such cases going to the notify 1016 * label does not have any meaning 1017 * (i.e. ctlfunc will be NULL), but we go 1018 * anyway since we might have to update 1019 * path MTU information. 1020 */ 1021 goto notify; 1022 } 1023 } 1024 notify: 1025 #ifndef PULLDOWN_TEST 1026 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 1027 #else 1028 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, 1029 sizeof(*icmp6) + sizeof(struct ip6_hdr)); 1030 if (icmp6 == NULL) { 1031 icmp6stat.icp6s_tooshort++; 1032 return (-1); 1033 } 1034 #endif 1035 1036 /* 1037 * retrieve parameters from the inner IPv6 header, and convert 1038 * them into sockaddr structures. 1039 * XXX: there is no guarantee that the source or destination 1040 * addresses of the inner packet are in the same scope as 1041 * the addresses of the icmp packet. But there is no other 1042 * way to determine the zone. 1043 */ 1044 eip6 = (struct ip6_hdr *)(icmp6 + 1); 1045 1046 bzero(&icmp6dst, sizeof(icmp6dst)); 1047 icmp6dst.sin6_len = sizeof(struct sockaddr_in6); 1048 icmp6dst.sin6_family = AF_INET6; 1049 if (finaldst == NULL) 1050 icmp6dst.sin6_addr = eip6->ip6_dst; 1051 else 1052 icmp6dst.sin6_addr = *finaldst; 1053 if (in6_setscope(&icmp6dst.sin6_addr, m->m_pkthdr.rcvif, NULL)) 1054 goto freeit; 1055 bzero(&icmp6src, sizeof(icmp6src)); 1056 icmp6src.sin6_len = sizeof(struct sockaddr_in6); 1057 icmp6src.sin6_family = AF_INET6; 1058 icmp6src.sin6_addr = eip6->ip6_src; 1059 if (in6_setscope(&icmp6src.sin6_addr, m->m_pkthdr.rcvif, NULL)) 1060 goto freeit; 1061 icmp6src.sin6_flowinfo = 1062 (eip6->ip6_flow & IPV6_FLOWLABEL_MASK); 1063 1064 if (finaldst == NULL) 1065 finaldst = &eip6->ip6_dst; 1066 ip6cp.ip6c_m = m; 1067 ip6cp.ip6c_icmp6 = icmp6; 1068 ip6cp.ip6c_ip6 = (struct ip6_hdr *)(icmp6 + 1); 1069 ip6cp.ip6c_off = eoff; 1070 ip6cp.ip6c_finaldst = finaldst; 1071 ip6cp.ip6c_src = &icmp6src; 1072 ip6cp.ip6c_nxt = nxt; 1073 1074 if (icmp6type == ICMP6_PACKET_TOO_BIG) { 1075 notifymtu = ntohl(icmp6->icmp6_mtu); 1076 ip6cp.ip6c_cmdarg = (void *)¬ifymtu; 1077 icmp6_mtudisc_update(&ip6cp, 1); /*XXX*/ 1078 } 1079 1080 ctlfunc = (void (*) __P((int, struct sockaddr *, void *))) 1081 (inet6sw[ip6_protox[nxt]].pr_ctlinput); 1082 if (ctlfunc) { 1083 (void) (*ctlfunc)(code, (struct sockaddr *)&icmp6dst, 1084 &ip6cp); 1085 } 1086 } 1087 *mp = m; 1088 return (0); 1089 1090 freeit: 1091 m_freem(m); 1092 return (-1); 1093 } 1094 1095 void 1096 icmp6_mtudisc_update(ip6cp, validated) 1097 struct ip6ctlparam *ip6cp; 1098 int validated; 1099 { 1100 struct in6_addr *dst = ip6cp->ip6c_finaldst; 1101 struct icmp6_hdr *icmp6 = ip6cp->ip6c_icmp6; 1102 struct mbuf *m = ip6cp->ip6c_m; /* will be necessary for scope issue */ 1103 u_int mtu = ntohl(icmp6->icmp6_mtu); 1104 struct in_conninfo inc; 1105 1106 #if 0 1107 /* 1108 * RFC2460 section 5, last paragraph. 1109 * even though minimum link MTU for IPv6 is IPV6_MMTU, 1110 * we may see ICMPv6 too big with mtu < IPV6_MMTU 1111 * due to packet translator in the middle. 1112 * see ip6_output() and ip6_getpmtu() "alwaysfrag" case for 1113 * special handling. 1114 */ 1115 if (mtu < IPV6_MMTU) 1116 return; 1117 #endif 1118 1119 /* 1120 * we reject ICMPv6 too big with abnormally small value. 1121 * XXX what is the good definition of "abnormally small"? 1122 */ 1123 if (mtu < sizeof(struct ip6_hdr) + sizeof(struct ip6_frag) + 8) 1124 return; 1125 1126 if (!validated) 1127 return; 1128 1129 bzero(&inc, sizeof(inc)); 1130 inc.inc_flags = 1; /* IPv6 */ 1131 inc.inc6_faddr = *dst; 1132 if (in6_setscope(&inc.inc6_faddr, m->m_pkthdr.rcvif, NULL)) 1133 return; 1134 1135 if (mtu < tcp_maxmtu6(&inc)) { 1136 tcp_hc_updatemtu(&inc, mtu); 1137 icmp6stat.icp6s_pmtuchg++; 1138 } 1139 } 1140 1141 /* 1142 * Process a Node Information Query packet, based on 1143 * draft-ietf-ipngwg-icmp-name-lookups-07. 1144 * 1145 * Spec incompatibilities: 1146 * - IPv6 Subject address handling 1147 * - IPv4 Subject address handling support missing 1148 * - Proxy reply (answer even if it's not for me) 1149 * - joins NI group address at in6_ifattach() time only, does not cope 1150 * with hostname changes by sethostname(3) 1151 */ 1152 #define hostnamelen strlen(hostname) 1153 static struct mbuf * 1154 ni6_input(m, off) 1155 struct mbuf *m; 1156 int off; 1157 { 1158 struct icmp6_nodeinfo *ni6, *nni6; 1159 struct mbuf *n = NULL; 1160 u_int16_t qtype; 1161 int subjlen; 1162 int replylen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo); 1163 struct ni_reply_fqdn *fqdn; 1164 int addrs; /* for NI_QTYPE_NODEADDR */ 1165 struct ifnet *ifp = NULL; /* for NI_QTYPE_NODEADDR */ 1166 struct in6_addr in6_subj; /* subject address */ 1167 struct ip6_hdr *ip6; 1168 int oldfqdn = 0; /* if 1, return pascal string (03 draft) */ 1169 char *subj = NULL; 1170 struct in6_ifaddr *ia6 = NULL; 1171 1172 ip6 = mtod(m, struct ip6_hdr *); 1173 #ifndef PULLDOWN_TEST 1174 ni6 = (struct icmp6_nodeinfo *)(mtod(m, caddr_t) + off); 1175 #else 1176 IP6_EXTHDR_GET(ni6, struct icmp6_nodeinfo *, m, off, sizeof(*ni6)); 1177 if (ni6 == NULL) { 1178 /* m is already reclaimed */ 1179 return (NULL); 1180 } 1181 #endif 1182 1183 /* 1184 * Validate IPv6 destination address. 1185 * 1186 * The Responder must discard the Query without further processing 1187 * unless it is one of the Responder's unicast or anycast addresses, or 1188 * a link-local scope multicast address which the Responder has joined. 1189 * [icmp-name-lookups-08, Section 4.] 1190 */ 1191 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 1192 if (!IN6_IS_ADDR_MC_LINKLOCAL(&ip6->ip6_dst)) 1193 goto bad; 1194 /* else it's a link-local multicast, fine */ 1195 } else { /* unicast or anycast */ 1196 if ((ia6 = ip6_getdstifaddr(m)) == NULL) 1197 goto bad; /* XXX impossible */ 1198 1199 if ((ia6->ia6_flags & IN6_IFF_TEMPORARY) && 1200 !(icmp6_nodeinfo & 4)) { 1201 nd6log((LOG_DEBUG, "ni6_input: ignore node info to " 1202 "a temporary address in %s:%d", 1203 __FILE__, __LINE__)); 1204 goto bad; 1205 } 1206 } 1207 1208 /* validate query Subject field. */ 1209 qtype = ntohs(ni6->ni_qtype); 1210 subjlen = m->m_pkthdr.len - off - sizeof(struct icmp6_nodeinfo); 1211 switch (qtype) { 1212 case NI_QTYPE_NOOP: 1213 case NI_QTYPE_SUPTYPES: 1214 /* 07 draft */ 1215 if (ni6->ni_code == ICMP6_NI_SUBJ_FQDN && subjlen == 0) 1216 break; 1217 /* FALLTHROUGH */ 1218 case NI_QTYPE_FQDN: 1219 case NI_QTYPE_NODEADDR: 1220 switch (ni6->ni_code) { 1221 case ICMP6_NI_SUBJ_IPV6: 1222 #if ICMP6_NI_SUBJ_IPV6 != 0 1223 case 0: 1224 #endif 1225 /* 1226 * backward compatibility - try to accept 03 draft 1227 * format, where no Subject is present. 1228 */ 1229 if (qtype == NI_QTYPE_FQDN && ni6->ni_code == 0 && 1230 subjlen == 0) { 1231 oldfqdn++; 1232 break; 1233 } 1234 #if ICMP6_NI_SUBJ_IPV6 != 0 1235 if (ni6->ni_code != ICMP6_NI_SUBJ_IPV6) 1236 goto bad; 1237 #endif 1238 1239 if (subjlen != sizeof(struct in6_addr)) 1240 goto bad; 1241 1242 /* 1243 * Validate Subject address. 1244 * 1245 * Not sure what exactly "address belongs to the node" 1246 * means in the spec, is it just unicast, or what? 1247 * 1248 * At this moment we consider Subject address as 1249 * "belong to the node" if the Subject address equals 1250 * to the IPv6 destination address; validation for 1251 * IPv6 destination address should have done enough 1252 * check for us. 1253 * 1254 * We do not do proxy at this moment. 1255 */ 1256 /* m_pulldown instead of copy? */ 1257 m_copydata(m, off + sizeof(struct icmp6_nodeinfo), 1258 subjlen, (caddr_t)&in6_subj); 1259 if (in6_setscope(&in6_subj, m->m_pkthdr.rcvif, NULL)) 1260 goto bad; 1261 1262 subj = (char *)&in6_subj; 1263 if (IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, &in6_subj)) 1264 break; 1265 1266 /* 1267 * XXX if we are to allow other cases, we should really 1268 * be careful about scope here. 1269 * basically, we should disallow queries toward IPv6 1270 * destination X with subject Y, 1271 * if scope(X) > scope(Y). 1272 * if we allow scope(X) > scope(Y), it will result in 1273 * information leakage across scope boundary. 1274 */ 1275 goto bad; 1276 1277 case ICMP6_NI_SUBJ_FQDN: 1278 /* 1279 * Validate Subject name with gethostname(3). 1280 * 1281 * The behavior may need some debate, since: 1282 * - we are not sure if the node has FQDN as 1283 * hostname (returned by gethostname(3)). 1284 * - the code does wildcard match for truncated names. 1285 * however, we are not sure if we want to perform 1286 * wildcard match, if gethostname(3) side has 1287 * truncated hostname. 1288 */ 1289 n = ni6_nametodns(hostname, hostnamelen, 0); 1290 if (!n || n->m_next || n->m_len == 0) 1291 goto bad; 1292 IP6_EXTHDR_GET(subj, char *, m, 1293 off + sizeof(struct icmp6_nodeinfo), subjlen); 1294 if (subj == NULL) 1295 goto bad; 1296 if (!ni6_dnsmatch(subj, subjlen, mtod(n, const char *), 1297 n->m_len)) { 1298 goto bad; 1299 } 1300 m_freem(n); 1301 n = NULL; 1302 break; 1303 1304 case ICMP6_NI_SUBJ_IPV4: /* XXX: to be implemented? */ 1305 default: 1306 goto bad; 1307 } 1308 break; 1309 } 1310 1311 /* refuse based on configuration. XXX ICMP6_NI_REFUSED? */ 1312 switch (qtype) { 1313 case NI_QTYPE_FQDN: 1314 if ((icmp6_nodeinfo & 1) == 0) 1315 goto bad; 1316 break; 1317 case NI_QTYPE_NODEADDR: 1318 if ((icmp6_nodeinfo & 2) == 0) 1319 goto bad; 1320 break; 1321 } 1322 1323 /* guess reply length */ 1324 switch (qtype) { 1325 case NI_QTYPE_NOOP: 1326 break; /* no reply data */ 1327 case NI_QTYPE_SUPTYPES: 1328 replylen += sizeof(u_int32_t); 1329 break; 1330 case NI_QTYPE_FQDN: 1331 /* XXX will append an mbuf */ 1332 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1333 break; 1334 case NI_QTYPE_NODEADDR: 1335 addrs = ni6_addrs(ni6, m, &ifp, (struct in6_addr *)subj); 1336 if ((replylen += addrs * (sizeof(struct in6_addr) + 1337 sizeof(u_int32_t))) > MCLBYTES) 1338 replylen = MCLBYTES; /* XXX: will truncate pkt later */ 1339 break; 1340 default: 1341 /* 1342 * XXX: We must return a reply with the ICMP6 code 1343 * `unknown Qtype' in this case. However we regard the case 1344 * as an FQDN query for backward compatibility. 1345 * Older versions set a random value to this field, 1346 * so it rarely varies in the defined qtypes. 1347 * But the mechanism is not reliable... 1348 * maybe we should obsolete older versions. 1349 */ 1350 qtype = NI_QTYPE_FQDN; 1351 /* XXX will append an mbuf */ 1352 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1353 oldfqdn++; 1354 break; 1355 } 1356 1357 /* allocate an mbuf to reply. */ 1358 MGETHDR(n, M_DONTWAIT, m->m_type); 1359 if (n == NULL) { 1360 m_freem(m); 1361 return (NULL); 1362 } 1363 M_MOVE_PKTHDR(n, m); /* just for recvif */ 1364 if (replylen > MHLEN) { 1365 if (replylen > MCLBYTES) { 1366 /* 1367 * XXX: should we try to allocate more? But MCLBYTES 1368 * is probably much larger than IPV6_MMTU... 1369 */ 1370 goto bad; 1371 } 1372 MCLGET(n, M_DONTWAIT); 1373 if ((n->m_flags & M_EXT) == 0) { 1374 goto bad; 1375 } 1376 } 1377 n->m_pkthdr.len = n->m_len = replylen; 1378 1379 /* copy mbuf header and IPv6 + Node Information base headers */ 1380 bcopy(mtod(m, caddr_t), mtod(n, caddr_t), sizeof(struct ip6_hdr)); 1381 nni6 = (struct icmp6_nodeinfo *)(mtod(n, struct ip6_hdr *) + 1); 1382 bcopy((caddr_t)ni6, (caddr_t)nni6, sizeof(struct icmp6_nodeinfo)); 1383 1384 /* qtype dependent procedure */ 1385 switch (qtype) { 1386 case NI_QTYPE_NOOP: 1387 nni6->ni_code = ICMP6_NI_SUCCESS; 1388 nni6->ni_flags = 0; 1389 break; 1390 case NI_QTYPE_SUPTYPES: 1391 { 1392 u_int32_t v; 1393 nni6->ni_code = ICMP6_NI_SUCCESS; 1394 nni6->ni_flags = htons(0x0000); /* raw bitmap */ 1395 /* supports NOOP, SUPTYPES, FQDN, and NODEADDR */ 1396 v = (u_int32_t)htonl(0x0000000f); 1397 bcopy(&v, nni6 + 1, sizeof(u_int32_t)); 1398 break; 1399 } 1400 case NI_QTYPE_FQDN: 1401 nni6->ni_code = ICMP6_NI_SUCCESS; 1402 fqdn = (struct ni_reply_fqdn *)(mtod(n, caddr_t) + 1403 sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo)); 1404 nni6->ni_flags = 0; /* XXX: meaningless TTL */ 1405 fqdn->ni_fqdn_ttl = 0; /* ditto. */ 1406 /* 1407 * XXX do we really have FQDN in variable "hostname"? 1408 */ 1409 n->m_next = ni6_nametodns(hostname, hostnamelen, oldfqdn); 1410 if (n->m_next == NULL) 1411 goto bad; 1412 /* XXX we assume that n->m_next is not a chain */ 1413 if (n->m_next->m_next != NULL) 1414 goto bad; 1415 n->m_pkthdr.len += n->m_next->m_len; 1416 break; 1417 case NI_QTYPE_NODEADDR: 1418 { 1419 int lenlim, copied; 1420 1421 nni6->ni_code = ICMP6_NI_SUCCESS; 1422 n->m_pkthdr.len = n->m_len = 1423 sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo); 1424 lenlim = M_TRAILINGSPACE(n); 1425 copied = ni6_store_addrs(ni6, nni6, ifp, lenlim); 1426 /* XXX: reset mbuf length */ 1427 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) + 1428 sizeof(struct icmp6_nodeinfo) + copied; 1429 break; 1430 } 1431 default: 1432 break; /* XXX impossible! */ 1433 } 1434 1435 nni6->ni_type = ICMP6_NI_REPLY; 1436 m_freem(m); 1437 return (n); 1438 1439 bad: 1440 m_freem(m); 1441 if (n) 1442 m_freem(n); 1443 return (NULL); 1444 } 1445 #undef hostnamelen 1446 1447 /* 1448 * make a mbuf with DNS-encoded string. no compression support. 1449 * 1450 * XXX names with less than 2 dots (like "foo" or "foo.section") will be 1451 * treated as truncated name (two \0 at the end). this is a wild guess. 1452 */ 1453 static struct mbuf * 1454 ni6_nametodns(name, namelen, old) 1455 const char *name; 1456 int namelen; 1457 int old; /* return pascal string if non-zero */ 1458 { 1459 struct mbuf *m; 1460 char *cp, *ep; 1461 const char *p, *q; 1462 int i, len, nterm; 1463 1464 if (old) 1465 len = namelen + 1; 1466 else 1467 len = MCLBYTES; 1468 1469 /* because MAXHOSTNAMELEN is usually 256, we use cluster mbuf */ 1470 MGET(m, M_DONTWAIT, MT_DATA); 1471 if (m && len > MLEN) { 1472 MCLGET(m, M_DONTWAIT); 1473 if ((m->m_flags & M_EXT) == 0) 1474 goto fail; 1475 } 1476 if (!m) 1477 goto fail; 1478 m->m_next = NULL; 1479 1480 if (old) { 1481 m->m_len = len; 1482 *mtod(m, char *) = namelen; 1483 bcopy(name, mtod(m, char *) + 1, namelen); 1484 return m; 1485 } else { 1486 m->m_len = 0; 1487 cp = mtod(m, char *); 1488 ep = mtod(m, char *) + M_TRAILINGSPACE(m); 1489 1490 /* if not certain about my name, return empty buffer */ 1491 if (namelen == 0) 1492 return m; 1493 1494 /* 1495 * guess if it looks like shortened hostname, or FQDN. 1496 * shortened hostname needs two trailing "\0". 1497 */ 1498 i = 0; 1499 for (p = name; p < name + namelen; p++) { 1500 if (*p && *p == '.') 1501 i++; 1502 } 1503 if (i < 2) 1504 nterm = 2; 1505 else 1506 nterm = 1; 1507 1508 p = name; 1509 while (cp < ep && p < name + namelen) { 1510 i = 0; 1511 for (q = p; q < name + namelen && *q && *q != '.'; q++) 1512 i++; 1513 /* result does not fit into mbuf */ 1514 if (cp + i + 1 >= ep) 1515 goto fail; 1516 /* 1517 * DNS label length restriction, RFC1035 page 8. 1518 * "i == 0" case is included here to avoid returning 1519 * 0-length label on "foo..bar". 1520 */ 1521 if (i <= 0 || i >= 64) 1522 goto fail; 1523 *cp++ = i; 1524 bcopy(p, cp, i); 1525 cp += i; 1526 p = q; 1527 if (p < name + namelen && *p == '.') 1528 p++; 1529 } 1530 /* termination */ 1531 if (cp + nterm >= ep) 1532 goto fail; 1533 while (nterm-- > 0) 1534 *cp++ = '\0'; 1535 m->m_len = cp - mtod(m, char *); 1536 return m; 1537 } 1538 1539 panic("should not reach here"); 1540 /* NOTREACHED */ 1541 1542 fail: 1543 if (m) 1544 m_freem(m); 1545 return NULL; 1546 } 1547 1548 /* 1549 * check if two DNS-encoded string matches. takes care of truncated 1550 * form (with \0\0 at the end). no compression support. 1551 * XXX upper/lowercase match (see RFC2065) 1552 */ 1553 static int 1554 ni6_dnsmatch(a, alen, b, blen) 1555 const char *a; 1556 int alen; 1557 const char *b; 1558 int blen; 1559 { 1560 const char *a0, *b0; 1561 int l; 1562 1563 /* simplest case - need validation? */ 1564 if (alen == blen && bcmp(a, b, alen) == 0) 1565 return 1; 1566 1567 a0 = a; 1568 b0 = b; 1569 1570 /* termination is mandatory */ 1571 if (alen < 2 || blen < 2) 1572 return 0; 1573 if (a0[alen - 1] != '\0' || b0[blen - 1] != '\0') 1574 return 0; 1575 alen--; 1576 blen--; 1577 1578 while (a - a0 < alen && b - b0 < blen) { 1579 if (a - a0 + 1 > alen || b - b0 + 1 > blen) 1580 return 0; 1581 1582 if ((signed char)a[0] < 0 || (signed char)b[0] < 0) 1583 return 0; 1584 /* we don't support compression yet */ 1585 if (a[0] >= 64 || b[0] >= 64) 1586 return 0; 1587 1588 /* truncated case */ 1589 if (a[0] == 0 && a - a0 == alen - 1) 1590 return 1; 1591 if (b[0] == 0 && b - b0 == blen - 1) 1592 return 1; 1593 if (a[0] == 0 || b[0] == 0) 1594 return 0; 1595 1596 if (a[0] != b[0]) 1597 return 0; 1598 l = a[0]; 1599 if (a - a0 + 1 + l > alen || b - b0 + 1 + l > blen) 1600 return 0; 1601 if (bcmp(a + 1, b + 1, l) != 0) 1602 return 0; 1603 1604 a += 1 + l; 1605 b += 1 + l; 1606 } 1607 1608 if (a - a0 == alen && b - b0 == blen) 1609 return 1; 1610 else 1611 return 0; 1612 } 1613 1614 /* 1615 * calculate the number of addresses to be returned in the node info reply. 1616 */ 1617 static int 1618 ni6_addrs(ni6, m, ifpp, subj) 1619 struct icmp6_nodeinfo *ni6; 1620 struct mbuf *m; 1621 struct ifnet **ifpp; 1622 struct in6_addr *subj; 1623 { 1624 struct ifnet *ifp; 1625 struct in6_ifaddr *ifa6; 1626 struct ifaddr *ifa; 1627 int addrs = 0, addrsofif, iffound = 0; 1628 int niflags = ni6->ni_flags; 1629 1630 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0) { 1631 switch (ni6->ni_code) { 1632 case ICMP6_NI_SUBJ_IPV6: 1633 if (subj == NULL) /* must be impossible... */ 1634 return (0); 1635 break; 1636 default: 1637 /* 1638 * XXX: we only support IPv6 subject address for 1639 * this Qtype. 1640 */ 1641 return (0); 1642 } 1643 } 1644 1645 IFNET_RLOCK(); 1646 for (ifp = TAILQ_FIRST(&ifnet); ifp; ifp = TAILQ_NEXT(ifp, if_list)) { 1647 addrsofif = 0; 1648 TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list) { 1649 if (ifa->ifa_addr->sa_family != AF_INET6) 1650 continue; 1651 ifa6 = (struct in6_ifaddr *)ifa; 1652 1653 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0 && 1654 IN6_ARE_ADDR_EQUAL(subj, &ifa6->ia_addr.sin6_addr)) 1655 iffound = 1; 1656 1657 /* 1658 * IPv4-mapped addresses can only be returned by a 1659 * Node Information proxy, since they represent 1660 * addresses of IPv4-only nodes, which perforce do 1661 * not implement this protocol. 1662 * [icmp-name-lookups-07, Section 5.4] 1663 * So we don't support NI_NODEADDR_FLAG_COMPAT in 1664 * this function at this moment. 1665 */ 1666 1667 /* What do we have to do about ::1? */ 1668 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1669 case IPV6_ADDR_SCOPE_LINKLOCAL: 1670 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0) 1671 continue; 1672 break; 1673 case IPV6_ADDR_SCOPE_SITELOCAL: 1674 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0) 1675 continue; 1676 break; 1677 case IPV6_ADDR_SCOPE_GLOBAL: 1678 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0) 1679 continue; 1680 break; 1681 default: 1682 continue; 1683 } 1684 1685 /* 1686 * check if anycast is okay. 1687 * XXX: just experimental. not in the spec. 1688 */ 1689 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 && 1690 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0) 1691 continue; /* we need only unicast addresses */ 1692 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 1693 (icmp6_nodeinfo & 4) == 0) { 1694 continue; 1695 } 1696 addrsofif++; /* count the address */ 1697 } 1698 if (iffound) { 1699 *ifpp = ifp; 1700 IFNET_RUNLOCK(); 1701 return (addrsofif); 1702 } 1703 1704 addrs += addrsofif; 1705 } 1706 IFNET_RUNLOCK(); 1707 1708 return (addrs); 1709 } 1710 1711 static int 1712 ni6_store_addrs(ni6, nni6, ifp0, resid) 1713 struct icmp6_nodeinfo *ni6, *nni6; 1714 struct ifnet *ifp0; 1715 int resid; 1716 { 1717 struct ifnet *ifp = ifp0 ? ifp0 : TAILQ_FIRST(&ifnet); 1718 struct in6_ifaddr *ifa6; 1719 struct ifaddr *ifa; 1720 struct ifnet *ifp_dep = NULL; 1721 int copied = 0, allow_deprecated = 0; 1722 u_char *cp = (u_char *)(nni6 + 1); 1723 int niflags = ni6->ni_flags; 1724 u_int32_t ltime; 1725 1726 if (ifp0 == NULL && !(niflags & NI_NODEADDR_FLAG_ALL)) 1727 return (0); /* needless to copy */ 1728 1729 IFNET_RLOCK(); 1730 again: 1731 1732 for (; ifp; ifp = TAILQ_NEXT(ifp, if_list)) { 1733 for (ifa = ifp->if_addrlist.tqh_first; ifa; 1734 ifa = ifa->ifa_list.tqe_next) { 1735 if (ifa->ifa_addr->sa_family != AF_INET6) 1736 continue; 1737 ifa6 = (struct in6_ifaddr *)ifa; 1738 1739 if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) != 0 && 1740 allow_deprecated == 0) { 1741 /* 1742 * prefererred address should be put before 1743 * deprecated addresses. 1744 */ 1745 1746 /* record the interface for later search */ 1747 if (ifp_dep == NULL) 1748 ifp_dep = ifp; 1749 1750 continue; 1751 } else if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) == 0 && 1752 allow_deprecated != 0) 1753 continue; /* we now collect deprecated addrs */ 1754 1755 /* What do we have to do about ::1? */ 1756 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1757 case IPV6_ADDR_SCOPE_LINKLOCAL: 1758 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0) 1759 continue; 1760 break; 1761 case IPV6_ADDR_SCOPE_SITELOCAL: 1762 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0) 1763 continue; 1764 break; 1765 case IPV6_ADDR_SCOPE_GLOBAL: 1766 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0) 1767 continue; 1768 break; 1769 default: 1770 continue; 1771 } 1772 1773 /* 1774 * check if anycast is okay. 1775 * XXX: just experimental. not in the spec. 1776 */ 1777 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 && 1778 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0) 1779 continue; 1780 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 1781 (icmp6_nodeinfo & 4) == 0) { 1782 continue; 1783 } 1784 1785 /* now we can copy the address */ 1786 if (resid < sizeof(struct in6_addr) + 1787 sizeof(u_int32_t)) { 1788 /* 1789 * We give up much more copy. 1790 * Set the truncate flag and return. 1791 */ 1792 nni6->ni_flags |= NI_NODEADDR_FLAG_TRUNCATE; 1793 IFNET_RUNLOCK(); 1794 return (copied); 1795 } 1796 1797 /* 1798 * Set the TTL of the address. 1799 * The TTL value should be one of the following 1800 * according to the specification: 1801 * 1802 * 1. The remaining lifetime of a DHCP lease on the 1803 * address, or 1804 * 2. The remaining Valid Lifetime of a prefix from 1805 * which the address was derived through Stateless 1806 * Autoconfiguration. 1807 * 1808 * Note that we currently do not support stateful 1809 * address configuration by DHCPv6, so the former 1810 * case can't happen. 1811 */ 1812 if (ifa6->ia6_lifetime.ia6t_expire == 0) 1813 ltime = ND6_INFINITE_LIFETIME; 1814 else { 1815 if (ifa6->ia6_lifetime.ia6t_expire > 1816 time_second) 1817 ltime = htonl(ifa6->ia6_lifetime.ia6t_expire - time_second); 1818 else 1819 ltime = 0; 1820 } 1821 1822 bcopy(<ime, cp, sizeof(u_int32_t)); 1823 cp += sizeof(u_int32_t); 1824 1825 /* copy the address itself */ 1826 bcopy(&ifa6->ia_addr.sin6_addr, cp, 1827 sizeof(struct in6_addr)); 1828 in6_clearscope((struct in6_addr *)cp); /* XXX */ 1829 cp += sizeof(struct in6_addr); 1830 1831 resid -= (sizeof(struct in6_addr) + sizeof(u_int32_t)); 1832 copied += (sizeof(struct in6_addr) + sizeof(u_int32_t)); 1833 } 1834 if (ifp0) /* we need search only on the specified IF */ 1835 break; 1836 } 1837 1838 if (allow_deprecated == 0 && ifp_dep != NULL) { 1839 ifp = ifp_dep; 1840 allow_deprecated = 1; 1841 1842 goto again; 1843 } 1844 1845 IFNET_RUNLOCK(); 1846 1847 return (copied); 1848 } 1849 1850 /* 1851 * XXX almost dup'ed code with rip6_input. 1852 */ 1853 static int 1854 icmp6_rip6_input(mp, off) 1855 struct mbuf **mp; 1856 int off; 1857 { 1858 struct mbuf *m = *mp; 1859 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1860 struct in6pcb *in6p; 1861 struct in6pcb *last = NULL; 1862 struct sockaddr_in6 fromsa; 1863 struct icmp6_hdr *icmp6; 1864 struct mbuf *opts = NULL; 1865 1866 #ifndef PULLDOWN_TEST 1867 /* this is assumed to be safe. */ 1868 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off); 1869 #else 1870 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 1871 if (icmp6 == NULL) { 1872 /* m is already reclaimed */ 1873 return (IPPROTO_DONE); 1874 } 1875 #endif 1876 1877 /* 1878 * XXX: the address may have embedded scope zone ID, which should be 1879 * hidden from applications. 1880 */ 1881 bzero(&fromsa, sizeof(fromsa)); 1882 fromsa.sin6_family = AF_INET6; 1883 fromsa.sin6_len = sizeof(struct sockaddr_in6); 1884 fromsa.sin6_addr = ip6->ip6_src; 1885 if (sa6_recoverscope(&fromsa)) { 1886 m_freem(m); 1887 return (IPPROTO_DONE); 1888 } 1889 1890 INP_INFO_RLOCK(&ripcbinfo); 1891 LIST_FOREACH(in6p, &ripcb, inp_list) { 1892 INP_LOCK(in6p); 1893 if ((in6p->inp_vflag & INP_IPV6) == 0) { 1894 docontinue: 1895 INP_UNLOCK(in6p); 1896 continue; 1897 } 1898 if (in6p->in6p_ip6_nxt != IPPROTO_ICMPV6) 1899 goto docontinue; 1900 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr) && 1901 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr, &ip6->ip6_dst)) 1902 goto docontinue; 1903 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr) && 1904 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr, &ip6->ip6_src)) 1905 goto docontinue; 1906 if (in6p->in6p_icmp6filt 1907 && ICMP6_FILTER_WILLBLOCK(icmp6->icmp6_type, 1908 in6p->in6p_icmp6filt)) 1909 goto docontinue; 1910 if (last) { 1911 struct mbuf *n = NULL; 1912 1913 /* 1914 * Recent network drivers tend to allocate a single 1915 * mbuf cluster, rather than to make a couple of 1916 * mbufs without clusters. Also, since the IPv6 code 1917 * path tries to avoid m_pullup(), it is highly 1918 * probable that we still have an mbuf cluster here 1919 * even though the necessary length can be stored in an 1920 * mbuf's internal buffer. 1921 * Meanwhile, the default size of the receive socket 1922 * buffer for raw sockets is not so large. This means 1923 * the possibility of packet loss is relatively higher 1924 * than before. To avoid this scenario, we copy the 1925 * received data to a separate mbuf that does not use 1926 * a cluster, if possible. 1927 * XXX: it is better to copy the data after stripping 1928 * intermediate headers. 1929 */ 1930 if ((m->m_flags & M_EXT) && m->m_next == NULL && 1931 m->m_len <= MHLEN) { 1932 MGET(n, M_DONTWAIT, m->m_type); 1933 if (n != NULL) { 1934 if (m_dup_pkthdr(n, m, M_NOWAIT)) { 1935 bcopy(m->m_data, n->m_data, 1936 m->m_len); 1937 n->m_len = m->m_len; 1938 } else { 1939 m_free(n); 1940 n = NULL; 1941 } 1942 } 1943 } 1944 if (n != NULL || 1945 (n = m_copy(m, 0, (int)M_COPYALL)) != NULL) { 1946 if (last->in6p_flags & IN6P_CONTROLOPTS) 1947 ip6_savecontrol(last, n, &opts); 1948 /* strip intermediate headers */ 1949 m_adj(n, off); 1950 if (sbappendaddr(&last->in6p_socket->so_rcv, 1951 (struct sockaddr *)&fromsa, n, opts) 1952 == 0) { 1953 /* should notify about lost packet */ 1954 m_freem(n); 1955 if (opts) { 1956 m_freem(opts); 1957 } 1958 } else 1959 sorwakeup(last->in6p_socket); 1960 opts = NULL; 1961 } 1962 INP_UNLOCK(last); 1963 } 1964 last = in6p; 1965 } 1966 if (last) { 1967 if (last->in6p_flags & IN6P_CONTROLOPTS) 1968 ip6_savecontrol(last, m, &opts); 1969 /* strip intermediate headers */ 1970 m_adj(m, off); 1971 1972 /* avoid using mbuf clusters if possible (see above) */ 1973 if ((m->m_flags & M_EXT) && m->m_next == NULL && 1974 m->m_len <= MHLEN) { 1975 struct mbuf *n; 1976 1977 MGET(n, M_DONTWAIT, m->m_type); 1978 if (n != NULL) { 1979 if (m_dup_pkthdr(n, m, M_NOWAIT)) { 1980 bcopy(m->m_data, n->m_data, m->m_len); 1981 n->m_len = m->m_len; 1982 1983 m_freem(m); 1984 m = n; 1985 } else { 1986 m_freem(n); 1987 n = NULL; 1988 } 1989 } 1990 } 1991 if (sbappendaddr(&last->in6p_socket->so_rcv, 1992 (struct sockaddr *)&fromsa, m, opts) == 0) { 1993 m_freem(m); 1994 if (opts) 1995 m_freem(opts); 1996 } else 1997 sorwakeup(last->in6p_socket); 1998 INP_UNLOCK(last); 1999 } else { 2000 m_freem(m); 2001 ip6stat.ip6s_delivered--; 2002 } 2003 INP_INFO_RUNLOCK(&ripcbinfo); 2004 return IPPROTO_DONE; 2005 } 2006 2007 /* 2008 * Reflect the ip6 packet back to the source. 2009 * OFF points to the icmp6 header, counted from the top of the mbuf. 2010 */ 2011 void 2012 icmp6_reflect(m, off) 2013 struct mbuf *m; 2014 size_t off; 2015 { 2016 struct ip6_hdr *ip6; 2017 struct icmp6_hdr *icmp6; 2018 struct in6_ifaddr *ia; 2019 int plen; 2020 int type, code; 2021 struct ifnet *outif = NULL; 2022 struct in6_addr origdst, *src = NULL; 2023 2024 /* too short to reflect */ 2025 if (off < sizeof(struct ip6_hdr)) { 2026 nd6log((LOG_DEBUG, 2027 "sanity fail: off=%lx, sizeof(ip6)=%lx in %s:%d\n", 2028 (u_long)off, (u_long)sizeof(struct ip6_hdr), 2029 __FILE__, __LINE__)); 2030 goto bad; 2031 } 2032 2033 /* 2034 * If there are extra headers between IPv6 and ICMPv6, strip 2035 * off that header first. 2036 */ 2037 #ifdef DIAGNOSTIC 2038 if (sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) > MHLEN) 2039 panic("assumption failed in icmp6_reflect"); 2040 #endif 2041 if (off > sizeof(struct ip6_hdr)) { 2042 size_t l; 2043 struct ip6_hdr nip6; 2044 2045 l = off - sizeof(struct ip6_hdr); 2046 m_copydata(m, 0, sizeof(nip6), (caddr_t)&nip6); 2047 m_adj(m, l); 2048 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 2049 if (m->m_len < l) { 2050 if ((m = m_pullup(m, l)) == NULL) 2051 return; 2052 } 2053 bcopy((caddr_t)&nip6, mtod(m, caddr_t), sizeof(nip6)); 2054 } else /* off == sizeof(struct ip6_hdr) */ { 2055 size_t l; 2056 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 2057 if (m->m_len < l) { 2058 if ((m = m_pullup(m, l)) == NULL) 2059 return; 2060 } 2061 } 2062 plen = m->m_pkthdr.len - sizeof(struct ip6_hdr); 2063 ip6 = mtod(m, struct ip6_hdr *); 2064 ip6->ip6_nxt = IPPROTO_ICMPV6; 2065 icmp6 = (struct icmp6_hdr *)(ip6 + 1); 2066 type = icmp6->icmp6_type; /* keep type for statistics */ 2067 code = icmp6->icmp6_code; /* ditto. */ 2068 2069 origdst = ip6->ip6_dst; 2070 /* 2071 * ip6_input() drops a packet if its src is multicast. 2072 * So, the src is never multicast. 2073 */ 2074 ip6->ip6_dst = ip6->ip6_src; 2075 2076 /* 2077 * If the incoming packet was addressed directly to us (i.e. unicast), 2078 * use dst as the src for the reply. 2079 * The IN6_IFF_NOTREADY case should be VERY rare, but is possible 2080 * (for example) when we encounter an error while forwarding procedure 2081 * destined to a duplicated address of ours. 2082 * Note that ip6_getdstifaddr() may fail if we are in an error handling 2083 * procedure of an outgoing packet of our own, in which case we need 2084 * to search in the ifaddr list. 2085 */ 2086 if (!IN6_IS_ADDR_MULTICAST(&origdst)) { 2087 if ((ia = ip6_getdstifaddr(m))) { 2088 if (!(ia->ia6_flags & 2089 (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY))) 2090 src = &ia->ia_addr.sin6_addr; 2091 } else { 2092 struct sockaddr_in6 d; 2093 2094 bzero(&d, sizeof(d)); 2095 d.sin6_family = AF_INET6; 2096 d.sin6_len = sizeof(d); 2097 d.sin6_addr = origdst; 2098 ia = (struct in6_ifaddr *) 2099 ifa_ifwithaddr((struct sockaddr *)&d); 2100 if (ia && 2101 !(ia->ia6_flags & 2102 (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY))) { 2103 src = &ia->ia_addr.sin6_addr; 2104 } 2105 } 2106 } 2107 2108 if (src == NULL) { 2109 int e; 2110 struct sockaddr_in6 sin6; 2111 struct route_in6 ro; 2112 2113 /* 2114 * This case matches to multicasts, our anycast, or unicasts 2115 * that we do not own. Select a source address based on the 2116 * source address of the erroneous packet. 2117 */ 2118 bzero(&sin6, sizeof(sin6)); 2119 sin6.sin6_family = AF_INET6; 2120 sin6.sin6_len = sizeof(sin6); 2121 sin6.sin6_addr = ip6->ip6_dst; /* zone ID should be embedded */ 2122 2123 bzero(&ro, sizeof(ro)); 2124 src = in6_selectsrc(&sin6, NULL, NULL, &ro, NULL, &outif, &e); 2125 if (ro.ro_rt) 2126 RTFREE(ro.ro_rt); /* XXX: we could use this */ 2127 if (src == NULL) { 2128 nd6log((LOG_DEBUG, 2129 "icmp6_reflect: source can't be determined: " 2130 "dst=%s, error=%d\n", 2131 ip6_sprintf(&sin6.sin6_addr), e)); 2132 goto bad; 2133 } 2134 } 2135 2136 ip6->ip6_src = *src; 2137 ip6->ip6_flow = 0; 2138 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2139 ip6->ip6_vfc |= IPV6_VERSION; 2140 ip6->ip6_nxt = IPPROTO_ICMPV6; 2141 if (outif) 2142 ip6->ip6_hlim = ND_IFINFO(outif)->chlim; 2143 else if (m->m_pkthdr.rcvif) { 2144 /* XXX: This may not be the outgoing interface */ 2145 ip6->ip6_hlim = ND_IFINFO(m->m_pkthdr.rcvif)->chlim; 2146 } else 2147 ip6->ip6_hlim = ip6_defhlim; 2148 2149 icmp6->icmp6_cksum = 0; 2150 icmp6->icmp6_cksum = in6_cksum(m, IPPROTO_ICMPV6, 2151 sizeof(struct ip6_hdr), plen); 2152 2153 /* 2154 * XXX option handling 2155 */ 2156 2157 m->m_flags &= ~(M_BCAST|M_MCAST); 2158 2159 ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL); 2160 if (outif) 2161 icmp6_ifoutstat_inc(outif, type, code); 2162 2163 return; 2164 2165 bad: 2166 m_freem(m); 2167 return; 2168 } 2169 2170 void 2171 icmp6_fasttimo() 2172 { 2173 2174 mld6_fasttimeo(); 2175 } 2176 2177 static const char * 2178 icmp6_redirect_diag(src6, dst6, tgt6) 2179 struct in6_addr *src6; 2180 struct in6_addr *dst6; 2181 struct in6_addr *tgt6; 2182 { 2183 static char buf[1024]; 2184 snprintf(buf, sizeof(buf), "(src=%s dst=%s tgt=%s)", 2185 ip6_sprintf(src6), ip6_sprintf(dst6), ip6_sprintf(tgt6)); 2186 return buf; 2187 } 2188 2189 void 2190 icmp6_redirect_input(m, off) 2191 struct mbuf *m; 2192 int off; 2193 { 2194 struct ifnet *ifp = m->m_pkthdr.rcvif; 2195 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 2196 struct nd_redirect *nd_rd; 2197 int icmp6len = ntohs(ip6->ip6_plen); 2198 char *lladdr = NULL; 2199 int lladdrlen = 0; 2200 u_char *redirhdr = NULL; 2201 int redirhdrlen = 0; 2202 struct rtentry *rt = NULL; 2203 int is_router; 2204 int is_onlink; 2205 struct in6_addr src6 = ip6->ip6_src; 2206 struct in6_addr redtgt6; 2207 struct in6_addr reddst6; 2208 union nd_opts ndopts; 2209 2210 if (!m || !ifp) 2211 return; 2212 2213 /* XXX if we are router, we don't update route by icmp6 redirect */ 2214 if (ip6_forwarding) 2215 goto freeit; 2216 if (!icmp6_rediraccept) 2217 goto freeit; 2218 2219 #ifndef PULLDOWN_TEST 2220 IP6_EXTHDR_CHECK(m, off, icmp6len,); 2221 nd_rd = (struct nd_redirect *)((caddr_t)ip6 + off); 2222 #else 2223 IP6_EXTHDR_GET(nd_rd, struct nd_redirect *, m, off, icmp6len); 2224 if (nd_rd == NULL) { 2225 icmp6stat.icp6s_tooshort++; 2226 return; 2227 } 2228 #endif 2229 redtgt6 = nd_rd->nd_rd_target; 2230 reddst6 = nd_rd->nd_rd_dst; 2231 2232 if (in6_setscope(&redtgt6, m->m_pkthdr.rcvif, NULL) || 2233 in6_setscope(&reddst6, m->m_pkthdr.rcvif, NULL)) { 2234 goto freeit; 2235 } 2236 2237 /* validation */ 2238 if (!IN6_IS_ADDR_LINKLOCAL(&src6)) { 2239 nd6log((LOG_ERR, 2240 "ICMP6 redirect sent from %s rejected; " 2241 "must be from linklocal\n", 2242 ip6_sprintf(&src6))); 2243 goto bad; 2244 } 2245 if (ip6->ip6_hlim != 255) { 2246 nd6log((LOG_ERR, 2247 "ICMP6 redirect sent from %s rejected; " 2248 "hlim=%d (must be 255)\n", 2249 ip6_sprintf(&src6), ip6->ip6_hlim)); 2250 goto bad; 2251 } 2252 { 2253 /* ip6->ip6_src must be equal to gw for icmp6->icmp6_reddst */ 2254 struct sockaddr_in6 sin6; 2255 struct in6_addr *gw6; 2256 2257 bzero(&sin6, sizeof(sin6)); 2258 sin6.sin6_family = AF_INET6; 2259 sin6.sin6_len = sizeof(struct sockaddr_in6); 2260 bcopy(&reddst6, &sin6.sin6_addr, sizeof(reddst6)); 2261 rt = rtalloc1((struct sockaddr *)&sin6, 0, 0UL); 2262 if (rt) { 2263 if (rt->rt_gateway == NULL || 2264 rt->rt_gateway->sa_family != AF_INET6) { 2265 nd6log((LOG_ERR, 2266 "ICMP6 redirect rejected; no route " 2267 "with inet6 gateway found for redirect dst: %s\n", 2268 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2269 RTFREE_LOCKED(rt); 2270 goto bad; 2271 } 2272 2273 gw6 = &(((struct sockaddr_in6 *)rt->rt_gateway)->sin6_addr); 2274 if (bcmp(&src6, gw6, sizeof(struct in6_addr)) != 0) { 2275 nd6log((LOG_ERR, 2276 "ICMP6 redirect rejected; " 2277 "not equal to gw-for-src=%s (must be same): " 2278 "%s\n", 2279 ip6_sprintf(gw6), 2280 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2281 RTFREE_LOCKED(rt); 2282 goto bad; 2283 } 2284 } else { 2285 nd6log((LOG_ERR, 2286 "ICMP6 redirect rejected; " 2287 "no route found for redirect dst: %s\n", 2288 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2289 goto bad; 2290 } 2291 RTFREE_LOCKED(rt); 2292 rt = NULL; 2293 } 2294 if (IN6_IS_ADDR_MULTICAST(&reddst6)) { 2295 nd6log((LOG_ERR, 2296 "ICMP6 redirect rejected; " 2297 "redirect dst must be unicast: %s\n", 2298 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2299 goto bad; 2300 } 2301 2302 is_router = is_onlink = 0; 2303 if (IN6_IS_ADDR_LINKLOCAL(&redtgt6)) 2304 is_router = 1; /* router case */ 2305 if (bcmp(&redtgt6, &reddst6, sizeof(redtgt6)) == 0) 2306 is_onlink = 1; /* on-link destination case */ 2307 if (!is_router && !is_onlink) { 2308 nd6log((LOG_ERR, 2309 "ICMP6 redirect rejected; " 2310 "neither router case nor onlink case: %s\n", 2311 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2312 goto bad; 2313 } 2314 /* validation passed */ 2315 2316 icmp6len -= sizeof(*nd_rd); 2317 nd6_option_init(nd_rd + 1, icmp6len, &ndopts); 2318 if (nd6_options(&ndopts) < 0) { 2319 nd6log((LOG_INFO, "icmp6_redirect_input: " 2320 "invalid ND option, rejected: %s\n", 2321 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2322 /* nd6_options have incremented stats */ 2323 goto freeit; 2324 } 2325 2326 if (ndopts.nd_opts_tgt_lladdr) { 2327 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 2328 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 2329 } 2330 2331 if (ndopts.nd_opts_rh) { 2332 redirhdrlen = ndopts.nd_opts_rh->nd_opt_rh_len; 2333 redirhdr = (u_char *)(ndopts.nd_opts_rh + 1); /* xxx */ 2334 } 2335 2336 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 2337 nd6log((LOG_INFO, 2338 "icmp6_redirect_input: lladdrlen mismatch for %s " 2339 "(if %d, icmp6 packet %d): %s\n", 2340 ip6_sprintf(&redtgt6), ifp->if_addrlen, lladdrlen - 2, 2341 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2342 goto bad; 2343 } 2344 2345 /* RFC 2461 8.3 */ 2346 nd6_cache_lladdr(ifp, &redtgt6, lladdr, lladdrlen, ND_REDIRECT, 2347 is_onlink ? ND_REDIRECT_ONLINK : ND_REDIRECT_ROUTER); 2348 2349 if (!is_onlink) { /* better router case. perform rtredirect. */ 2350 /* perform rtredirect */ 2351 struct sockaddr_in6 sdst; 2352 struct sockaddr_in6 sgw; 2353 struct sockaddr_in6 ssrc; 2354 2355 bzero(&sdst, sizeof(sdst)); 2356 bzero(&sgw, sizeof(sgw)); 2357 bzero(&ssrc, sizeof(ssrc)); 2358 sdst.sin6_family = sgw.sin6_family = ssrc.sin6_family = AF_INET6; 2359 sdst.sin6_len = sgw.sin6_len = ssrc.sin6_len = 2360 sizeof(struct sockaddr_in6); 2361 bcopy(&redtgt6, &sgw.sin6_addr, sizeof(struct in6_addr)); 2362 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2363 bcopy(&src6, &ssrc.sin6_addr, sizeof(struct in6_addr)); 2364 rtredirect((struct sockaddr *)&sdst, (struct sockaddr *)&sgw, 2365 (struct sockaddr *)NULL, RTF_GATEWAY | RTF_HOST, 2366 (struct sockaddr *)&ssrc); 2367 } 2368 /* finally update cached route in each socket via pfctlinput */ 2369 { 2370 struct sockaddr_in6 sdst; 2371 2372 bzero(&sdst, sizeof(sdst)); 2373 sdst.sin6_family = AF_INET6; 2374 sdst.sin6_len = sizeof(struct sockaddr_in6); 2375 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2376 pfctlinput(PRC_REDIRECT_HOST, (struct sockaddr *)&sdst); 2377 #if defined(IPSEC) || defined(FAST_IPSEC) 2378 key_sa_routechange((struct sockaddr *)&sdst); 2379 #endif 2380 } 2381 2382 freeit: 2383 m_freem(m); 2384 return; 2385 2386 bad: 2387 icmp6stat.icp6s_badredirect++; 2388 m_freem(m); 2389 } 2390 2391 void 2392 icmp6_redirect_output(m0, rt) 2393 struct mbuf *m0; 2394 struct rtentry *rt; 2395 { 2396 struct ifnet *ifp; /* my outgoing interface */ 2397 struct in6_addr *ifp_ll6; 2398 struct in6_addr *router_ll6; 2399 struct ip6_hdr *sip6; /* m0 as struct ip6_hdr */ 2400 struct mbuf *m = NULL; /* newly allocated one */ 2401 struct ip6_hdr *ip6; /* m as struct ip6_hdr */ 2402 struct nd_redirect *nd_rd; 2403 size_t maxlen; 2404 u_char *p; 2405 struct ifnet *outif = NULL; 2406 struct sockaddr_in6 src_sa; 2407 2408 icmp6_errcount(&icmp6stat.icp6s_outerrhist, ND_REDIRECT, 0); 2409 2410 /* if we are not router, we don't send icmp6 redirect */ 2411 if (!ip6_forwarding || ip6_accept_rtadv) 2412 goto fail; 2413 2414 /* sanity check */ 2415 if (!m0 || !rt || !(rt->rt_flags & RTF_UP) || !(ifp = rt->rt_ifp)) 2416 goto fail; 2417 2418 /* 2419 * Address check: 2420 * the source address must identify a neighbor, and 2421 * the destination address must not be a multicast address 2422 * [RFC 2461, sec 8.2] 2423 */ 2424 sip6 = mtod(m0, struct ip6_hdr *); 2425 bzero(&src_sa, sizeof(src_sa)); 2426 src_sa.sin6_family = AF_INET6; 2427 src_sa.sin6_len = sizeof(src_sa); 2428 src_sa.sin6_addr = sip6->ip6_src; 2429 if (nd6_is_addr_neighbor(&src_sa, ifp) == 0) 2430 goto fail; 2431 if (IN6_IS_ADDR_MULTICAST(&sip6->ip6_dst)) 2432 goto fail; /* what should we do here? */ 2433 2434 /* rate limit */ 2435 if (icmp6_ratelimit(&sip6->ip6_src, ND_REDIRECT, 0)) 2436 goto fail; 2437 2438 /* 2439 * Since we are going to append up to 1280 bytes (= IPV6_MMTU), 2440 * we almost always ask for an mbuf cluster for simplicity. 2441 * (MHLEN < IPV6_MMTU is almost always true) 2442 */ 2443 #if IPV6_MMTU >= MCLBYTES 2444 # error assumption failed about IPV6_MMTU and MCLBYTES 2445 #endif 2446 MGETHDR(m, M_DONTWAIT, MT_HEADER); 2447 if (m && IPV6_MMTU >= MHLEN) 2448 MCLGET(m, M_DONTWAIT); 2449 if (!m) 2450 goto fail; 2451 m->m_pkthdr.rcvif = NULL; 2452 m->m_len = 0; 2453 maxlen = M_TRAILINGSPACE(m); 2454 maxlen = min(IPV6_MMTU, maxlen); 2455 /* just for safety */ 2456 if (maxlen < sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) + 2457 ((sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7)) { 2458 goto fail; 2459 } 2460 2461 { 2462 /* get ip6 linklocal address for ifp(my outgoing interface). */ 2463 struct in6_ifaddr *ia; 2464 if ((ia = in6ifa_ifpforlinklocal(ifp, 2465 IN6_IFF_NOTREADY| 2466 IN6_IFF_ANYCAST)) == NULL) 2467 goto fail; 2468 ifp_ll6 = &ia->ia_addr.sin6_addr; 2469 } 2470 2471 /* get ip6 linklocal address for the router. */ 2472 if (rt->rt_gateway && (rt->rt_flags & RTF_GATEWAY)) { 2473 struct sockaddr_in6 *sin6; 2474 sin6 = (struct sockaddr_in6 *)rt->rt_gateway; 2475 router_ll6 = &sin6->sin6_addr; 2476 if (!IN6_IS_ADDR_LINKLOCAL(router_ll6)) 2477 router_ll6 = (struct in6_addr *)NULL; 2478 } else 2479 router_ll6 = (struct in6_addr *)NULL; 2480 2481 /* ip6 */ 2482 ip6 = mtod(m, struct ip6_hdr *); 2483 ip6->ip6_flow = 0; 2484 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2485 ip6->ip6_vfc |= IPV6_VERSION; 2486 /* ip6->ip6_plen will be set later */ 2487 ip6->ip6_nxt = IPPROTO_ICMPV6; 2488 ip6->ip6_hlim = 255; 2489 /* ip6->ip6_src must be linklocal addr for my outgoing if. */ 2490 bcopy(ifp_ll6, &ip6->ip6_src, sizeof(struct in6_addr)); 2491 bcopy(&sip6->ip6_src, &ip6->ip6_dst, sizeof(struct in6_addr)); 2492 2493 /* ND Redirect */ 2494 nd_rd = (struct nd_redirect *)(ip6 + 1); 2495 nd_rd->nd_rd_type = ND_REDIRECT; 2496 nd_rd->nd_rd_code = 0; 2497 nd_rd->nd_rd_reserved = 0; 2498 if (rt->rt_flags & RTF_GATEWAY) { 2499 /* 2500 * nd_rd->nd_rd_target must be a link-local address in 2501 * better router cases. 2502 */ 2503 if (!router_ll6) 2504 goto fail; 2505 bcopy(router_ll6, &nd_rd->nd_rd_target, 2506 sizeof(nd_rd->nd_rd_target)); 2507 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2508 sizeof(nd_rd->nd_rd_dst)); 2509 } else { 2510 /* make sure redtgt == reddst */ 2511 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_target, 2512 sizeof(nd_rd->nd_rd_target)); 2513 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2514 sizeof(nd_rd->nd_rd_dst)); 2515 } 2516 2517 p = (u_char *)(nd_rd + 1); 2518 2519 if (!router_ll6) 2520 goto nolladdropt; 2521 2522 { 2523 /* target lladdr option */ 2524 struct rtentry *rt_router = NULL; 2525 int len; 2526 struct sockaddr_dl *sdl; 2527 struct nd_opt_hdr *nd_opt; 2528 char *lladdr; 2529 2530 rt_router = nd6_lookup(router_ll6, 0, ifp); 2531 if (!rt_router) 2532 goto nolladdropt; 2533 len = sizeof(*nd_opt) + ifp->if_addrlen; 2534 len = (len + 7) & ~7; /* round by 8 */ 2535 /* safety check */ 2536 if (len + (p - (u_char *)ip6) > maxlen) 2537 goto nolladdropt; 2538 if (!(rt_router->rt_flags & RTF_GATEWAY) && 2539 (rt_router->rt_flags & RTF_LLINFO) && 2540 (rt_router->rt_gateway->sa_family == AF_LINK) && 2541 (sdl = (struct sockaddr_dl *)rt_router->rt_gateway) && 2542 sdl->sdl_alen) { 2543 nd_opt = (struct nd_opt_hdr *)p; 2544 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 2545 nd_opt->nd_opt_len = len >> 3; 2546 lladdr = (char *)(nd_opt + 1); 2547 bcopy(LLADDR(sdl), lladdr, ifp->if_addrlen); 2548 p += len; 2549 } 2550 } 2551 nolladdropt:; 2552 2553 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2554 2555 /* just to be safe */ 2556 #ifdef M_DECRYPTED /*not openbsd*/ 2557 if (m0->m_flags & M_DECRYPTED) 2558 goto noredhdropt; 2559 #endif 2560 if (p - (u_char *)ip6 > maxlen) 2561 goto noredhdropt; 2562 2563 { 2564 /* redirected header option */ 2565 int len; 2566 struct nd_opt_rd_hdr *nd_opt_rh; 2567 2568 /* 2569 * compute the maximum size for icmp6 redirect header option. 2570 * XXX room for auth header? 2571 */ 2572 len = maxlen - (p - (u_char *)ip6); 2573 len &= ~7; 2574 2575 /* This is just for simplicity. */ 2576 if (m0->m_pkthdr.len != m0->m_len) { 2577 if (m0->m_next) { 2578 m_freem(m0->m_next); 2579 m0->m_next = NULL; 2580 } 2581 m0->m_pkthdr.len = m0->m_len; 2582 } 2583 2584 /* 2585 * Redirected header option spec (RFC2461 4.6.3) talks nothing 2586 * about padding/truncate rule for the original IP packet. 2587 * From the discussion on IPv6imp in Feb 1999, 2588 * the consensus was: 2589 * - "attach as much as possible" is the goal 2590 * - pad if not aligned (original size can be guessed by 2591 * original ip6 header) 2592 * Following code adds the padding if it is simple enough, 2593 * and truncates if not. 2594 */ 2595 if (m0->m_next || m0->m_pkthdr.len != m0->m_len) 2596 panic("assumption failed in %s:%d", __FILE__, 2597 __LINE__); 2598 2599 if (len - sizeof(*nd_opt_rh) < m0->m_pkthdr.len) { 2600 /* not enough room, truncate */ 2601 m0->m_pkthdr.len = m0->m_len = len - 2602 sizeof(*nd_opt_rh); 2603 } else { 2604 /* enough room, pad or truncate */ 2605 size_t extra; 2606 2607 extra = m0->m_pkthdr.len % 8; 2608 if (extra) { 2609 /* pad if easy enough, truncate if not */ 2610 if (8 - extra <= M_TRAILINGSPACE(m0)) { 2611 /* pad */ 2612 m0->m_len += (8 - extra); 2613 m0->m_pkthdr.len += (8 - extra); 2614 } else { 2615 /* truncate */ 2616 m0->m_pkthdr.len -= extra; 2617 m0->m_len -= extra; 2618 } 2619 } 2620 len = m0->m_pkthdr.len + sizeof(*nd_opt_rh); 2621 m0->m_pkthdr.len = m0->m_len = len - 2622 sizeof(*nd_opt_rh); 2623 } 2624 2625 nd_opt_rh = (struct nd_opt_rd_hdr *)p; 2626 bzero(nd_opt_rh, sizeof(*nd_opt_rh)); 2627 nd_opt_rh->nd_opt_rh_type = ND_OPT_REDIRECTED_HEADER; 2628 nd_opt_rh->nd_opt_rh_len = len >> 3; 2629 p += sizeof(*nd_opt_rh); 2630 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2631 2632 /* connect m0 to m */ 2633 m_tag_delete_chain(m0, NULL); 2634 m0->m_flags &= ~M_PKTHDR; 2635 m->m_next = m0; 2636 m->m_pkthdr.len = m->m_len + m0->m_len; 2637 m0 = NULL; 2638 } 2639 noredhdropt:; 2640 if (m0) { 2641 m_freem(m0); 2642 m0 = NULL; 2643 } 2644 2645 /* XXX: clear embedded link IDs in the inner header */ 2646 in6_clearscope(&sip6->ip6_src); 2647 in6_clearscope(&sip6->ip6_dst); 2648 in6_clearscope(&nd_rd->nd_rd_target); 2649 in6_clearscope(&nd_rd->nd_rd_dst); 2650 2651 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr)); 2652 2653 nd_rd->nd_rd_cksum = 0; 2654 nd_rd->nd_rd_cksum = in6_cksum(m, IPPROTO_ICMPV6, 2655 sizeof(*ip6), ntohs(ip6->ip6_plen)); 2656 2657 /* send the packet to outside... */ 2658 ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL); 2659 if (outif) { 2660 icmp6_ifstat_inc(outif, ifs6_out_msg); 2661 icmp6_ifstat_inc(outif, ifs6_out_redirect); 2662 } 2663 icmp6stat.icp6s_outhist[ND_REDIRECT]++; 2664 2665 return; 2666 2667 fail: 2668 if (m) 2669 m_freem(m); 2670 if (m0) 2671 m_freem(m0); 2672 } 2673 2674 /* 2675 * ICMPv6 socket option processing. 2676 */ 2677 int 2678 icmp6_ctloutput(so, sopt) 2679 struct socket *so; 2680 struct sockopt *sopt; 2681 { 2682 int error = 0; 2683 int optlen; 2684 struct inpcb *inp = sotoinpcb(so); 2685 int level, op, optname; 2686 2687 if (sopt) { 2688 level = sopt->sopt_level; 2689 op = sopt->sopt_dir; 2690 optname = sopt->sopt_name; 2691 optlen = sopt->sopt_valsize; 2692 } else 2693 level = op = optname = optlen = 0; 2694 2695 if (level != IPPROTO_ICMPV6) { 2696 return EINVAL; 2697 } 2698 2699 switch (op) { 2700 case PRCO_SETOPT: 2701 switch (optname) { 2702 case ICMP6_FILTER: 2703 { 2704 struct icmp6_filter *p; 2705 2706 if (optlen != sizeof(*p)) { 2707 error = EMSGSIZE; 2708 break; 2709 } 2710 if (inp->in6p_icmp6filt == NULL) { 2711 error = EINVAL; 2712 break; 2713 } 2714 error = sooptcopyin(sopt, inp->in6p_icmp6filt, optlen, 2715 optlen); 2716 break; 2717 } 2718 2719 default: 2720 error = ENOPROTOOPT; 2721 break; 2722 } 2723 break; 2724 2725 case PRCO_GETOPT: 2726 switch (optname) { 2727 case ICMP6_FILTER: 2728 { 2729 if (inp->in6p_icmp6filt == NULL) { 2730 error = EINVAL; 2731 break; 2732 } 2733 error = sooptcopyout(sopt, inp->in6p_icmp6filt, 2734 sizeof(struct icmp6_filter)); 2735 break; 2736 } 2737 2738 default: 2739 error = ENOPROTOOPT; 2740 break; 2741 } 2742 break; 2743 } 2744 2745 return (error); 2746 } 2747 2748 /* 2749 * Perform rate limit check. 2750 * Returns 0 if it is okay to send the icmp6 packet. 2751 * Returns 1 if the router SHOULD NOT send this icmp6 packet due to rate 2752 * limitation. 2753 * 2754 * XXX per-destination/type check necessary? 2755 */ 2756 static int 2757 icmp6_ratelimit(dst, type, code) 2758 const struct in6_addr *dst; /* not used at this moment */ 2759 const int type; /* not used at this moment */ 2760 const int code; /* not used at this moment */ 2761 { 2762 int ret; 2763 2764 ret = 0; /* okay to send */ 2765 2766 /* PPS limit */ 2767 if (!ppsratecheck(&icmp6errppslim_last, &icmp6errpps_count, 2768 icmp6errppslim)) { 2769 /* The packet is subject to rate limit */ 2770 ret++; 2771 } 2772 2773 return ret; 2774 } 2775