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 <netipsec/ipsec.h> 104 #include <netipsec/key.h> 105 #endif 106 107 extern struct domain inet6domain; 108 109 struct icmp6stat icmp6stat; 110 111 extern struct inpcbinfo ripcbinfo; 112 extern struct inpcbhead ripcb; 113 extern int icmp6errppslim; 114 static int icmp6errpps_count = 0; 115 static struct timeval icmp6errppslim_last; 116 extern int icmp6_nodeinfo; 117 118 static void icmp6_errcount __P((struct icmp6errstat *, int, int)); 119 static int icmp6_rip6_input __P((struct mbuf **, int)); 120 static int icmp6_ratelimit __P((const struct in6_addr *, const int, const int)); 121 static const char *icmp6_redirect_diag __P((struct in6_addr *, 122 struct in6_addr *, struct in6_addr *)); 123 static struct mbuf *ni6_input __P((struct mbuf *, int)); 124 static struct mbuf *ni6_nametodns __P((const char *, int, int)); 125 static int ni6_dnsmatch __P((const char *, int, const char *, int)); 126 static int ni6_addrs __P((struct icmp6_nodeinfo *, struct mbuf *, 127 struct ifnet **, struct in6_addr *)); 128 static int ni6_store_addrs __P((struct icmp6_nodeinfo *, struct icmp6_nodeinfo *, 129 struct ifnet *, int)); 130 static int icmp6_notify_error __P((struct mbuf **, int, int, int)); 131 132 133 void 134 icmp6_init(void) 135 { 136 137 mld6_init(); 138 } 139 140 static void 141 icmp6_errcount(struct icmp6errstat *stat, int type, int code) 142 { 143 switch (type) { 144 case ICMP6_DST_UNREACH: 145 switch (code) { 146 case ICMP6_DST_UNREACH_NOROUTE: 147 stat->icp6errs_dst_unreach_noroute++; 148 return; 149 case ICMP6_DST_UNREACH_ADMIN: 150 stat->icp6errs_dst_unreach_admin++; 151 return; 152 case ICMP6_DST_UNREACH_BEYONDSCOPE: 153 stat->icp6errs_dst_unreach_beyondscope++; 154 return; 155 case ICMP6_DST_UNREACH_ADDR: 156 stat->icp6errs_dst_unreach_addr++; 157 return; 158 case ICMP6_DST_UNREACH_NOPORT: 159 stat->icp6errs_dst_unreach_noport++; 160 return; 161 } 162 break; 163 case ICMP6_PACKET_TOO_BIG: 164 stat->icp6errs_packet_too_big++; 165 return; 166 case ICMP6_TIME_EXCEEDED: 167 switch (code) { 168 case ICMP6_TIME_EXCEED_TRANSIT: 169 stat->icp6errs_time_exceed_transit++; 170 return; 171 case ICMP6_TIME_EXCEED_REASSEMBLY: 172 stat->icp6errs_time_exceed_reassembly++; 173 return; 174 } 175 break; 176 case ICMP6_PARAM_PROB: 177 switch (code) { 178 case ICMP6_PARAMPROB_HEADER: 179 stat->icp6errs_paramprob_header++; 180 return; 181 case ICMP6_PARAMPROB_NEXTHEADER: 182 stat->icp6errs_paramprob_nextheader++; 183 return; 184 case ICMP6_PARAMPROB_OPTION: 185 stat->icp6errs_paramprob_option++; 186 return; 187 } 188 break; 189 case ND_REDIRECT: 190 stat->icp6errs_redirect++; 191 return; 192 } 193 stat->icp6errs_unknown++; 194 } 195 196 /* 197 * A wrapper function for icmp6_error() necessary when the erroneous packet 198 * may not contain enough scope zone information. 199 */ 200 void 201 icmp6_error2(struct mbuf *m, int type, int code, int param, 202 struct ifnet *ifp) 203 { 204 struct ip6_hdr *ip6; 205 206 if (ifp == NULL) 207 return; 208 209 #ifndef PULLDOWN_TEST 210 IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), ); 211 #else 212 if (m->m_len < sizeof(struct ip6_hdr)) { 213 m = m_pullup(m, sizeof(struct ip6_hdr)); 214 if (m == NULL) 215 return; 216 } 217 #endif 218 219 ip6 = mtod(m, struct ip6_hdr *); 220 221 if (in6_setscope(&ip6->ip6_src, ifp, NULL) != 0) 222 return; 223 if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0) 224 return; 225 226 icmp6_error(m, type, code, param); 227 } 228 229 /* 230 * Generate an error packet of type error in response to bad IP6 packet. 231 */ 232 void 233 icmp6_error(struct mbuf *m, int type, int code, int param) 234 { 235 struct ip6_hdr *oip6, *nip6; 236 struct icmp6_hdr *icmp6; 237 u_int preplen; 238 int off; 239 int nxt; 240 241 icmp6stat.icp6s_error++; 242 243 /* count per-type-code statistics */ 244 icmp6_errcount(&icmp6stat.icp6s_outerrhist, type, code); 245 246 #ifdef M_DECRYPTED /*not openbsd*/ 247 if (m->m_flags & M_DECRYPTED) { 248 icmp6stat.icp6s_canterror++; 249 goto freeit; 250 } 251 #endif 252 253 #ifndef PULLDOWN_TEST 254 IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), ); 255 #else 256 if (m->m_len < sizeof(struct ip6_hdr)) { 257 m = m_pullup(m, sizeof(struct ip6_hdr)); 258 if (m == NULL) 259 return; 260 } 261 #endif 262 oip6 = mtod(m, struct ip6_hdr *); 263 264 /* 265 * If the destination address of the erroneous packet is a multicast 266 * address, or the packet was sent using link-layer multicast, 267 * we should basically suppress sending an error (RFC 2463, Section 268 * 2.4). 269 * We have two exceptions (the item e.2 in that section): 270 * - the Pakcet Too Big message can be sent for path MTU discovery. 271 * - the Parameter Problem Message that can be allowed an icmp6 error 272 * in the option type field. This check has been done in 273 * ip6_unknown_opt(), so we can just check the type and code. 274 */ 275 if ((m->m_flags & (M_BCAST|M_MCAST) || 276 IN6_IS_ADDR_MULTICAST(&oip6->ip6_dst)) && 277 (type != ICMP6_PACKET_TOO_BIG && 278 (type != ICMP6_PARAM_PROB || 279 code != ICMP6_PARAMPROB_OPTION))) 280 goto freeit; 281 282 /* 283 * RFC 2463, 2.4 (e.5): source address check. 284 * XXX: the case of anycast source? 285 */ 286 if (IN6_IS_ADDR_UNSPECIFIED(&oip6->ip6_src) || 287 IN6_IS_ADDR_MULTICAST(&oip6->ip6_src)) 288 goto freeit; 289 290 /* 291 * If we are about to send ICMPv6 against ICMPv6 error/redirect, 292 * don't do it. 293 */ 294 nxt = -1; 295 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); 296 if (off >= 0 && nxt == IPPROTO_ICMPV6) { 297 struct icmp6_hdr *icp; 298 299 #ifndef PULLDOWN_TEST 300 IP6_EXTHDR_CHECK(m, 0, off + sizeof(struct icmp6_hdr), ); 301 icp = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 302 #else 303 IP6_EXTHDR_GET(icp, struct icmp6_hdr *, m, off, 304 sizeof(*icp)); 305 if (icp == NULL) { 306 icmp6stat.icp6s_tooshort++; 307 return; 308 } 309 #endif 310 if (icp->icmp6_type < ICMP6_ECHO_REQUEST || 311 icp->icmp6_type == ND_REDIRECT) { 312 /* 313 * ICMPv6 error 314 * Special case: for redirect (which is 315 * informational) we must not send icmp6 error. 316 */ 317 icmp6stat.icp6s_canterror++; 318 goto freeit; 319 } else { 320 /* ICMPv6 informational - send the error */ 321 } 322 } else { 323 /* non-ICMPv6 - send the error */ 324 } 325 326 oip6 = mtod(m, struct ip6_hdr *); /* adjust pointer */ 327 328 /* Finally, do rate limitation check. */ 329 if (icmp6_ratelimit(&oip6->ip6_src, type, code)) { 330 icmp6stat.icp6s_toofreq++; 331 goto freeit; 332 } 333 334 /* 335 * OK, ICMP6 can be generated. 336 */ 337 338 if (m->m_pkthdr.len >= ICMPV6_PLD_MAXLEN) 339 m_adj(m, ICMPV6_PLD_MAXLEN - m->m_pkthdr.len); 340 341 preplen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 342 M_PREPEND(m, preplen, M_DONTWAIT); 343 if (m && m->m_len < preplen) 344 m = m_pullup(m, preplen); 345 if (m == NULL) { 346 nd6log((LOG_DEBUG, "ENOBUFS in icmp6_error %d\n", __LINE__)); 347 return; 348 } 349 350 nip6 = mtod(m, struct ip6_hdr *); 351 nip6->ip6_src = oip6->ip6_src; 352 nip6->ip6_dst = oip6->ip6_dst; 353 354 in6_clearscope(&oip6->ip6_src); 355 in6_clearscope(&oip6->ip6_dst); 356 357 icmp6 = (struct icmp6_hdr *)(nip6 + 1); 358 icmp6->icmp6_type = type; 359 icmp6->icmp6_code = code; 360 icmp6->icmp6_pptr = htonl((u_int32_t)param); 361 362 /* 363 * icmp6_reflect() is designed to be in the input path. 364 * icmp6_error() can be called from both input and output path, 365 * and if we are in output path rcvif could contain bogus value. 366 * clear m->m_pkthdr.rcvif for safety, we should have enough scope 367 * information in ip header (nip6). 368 */ 369 m->m_pkthdr.rcvif = NULL; 370 371 icmp6stat.icp6s_outhist[type]++; 372 icmp6_reflect(m, sizeof(struct ip6_hdr)); /* header order: IPv6 - ICMPv6 */ 373 374 return; 375 376 freeit: 377 /* 378 * If we can't tell whether or not we can generate ICMP6, free it. 379 */ 380 m_freem(m); 381 } 382 383 /* 384 * Process a received ICMP6 message. 385 */ 386 int 387 icmp6_input(struct mbuf **mp, int *offp, int proto) 388 { 389 struct mbuf *m = *mp, *n; 390 struct ip6_hdr *ip6, *nip6; 391 struct icmp6_hdr *icmp6, *nicmp6; 392 int off = *offp; 393 int icmp6len = m->m_pkthdr.len - *offp; 394 int code, sum, noff; 395 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 396 397 #ifndef PULLDOWN_TEST 398 IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_hdr), IPPROTO_DONE); 399 /* m might change if M_LOOP. So, call mtod after this */ 400 #endif 401 402 /* 403 * Locate icmp6 structure in mbuf, and check 404 * that not corrupted and of at least minimum length 405 */ 406 407 ip6 = mtod(m, struct ip6_hdr *); 408 if (icmp6len < sizeof(struct icmp6_hdr)) { 409 icmp6stat.icp6s_tooshort++; 410 goto freeit; 411 } 412 413 /* 414 * calculate the checksum 415 */ 416 #ifndef PULLDOWN_TEST 417 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off); 418 #else 419 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 420 if (icmp6 == NULL) { 421 icmp6stat.icp6s_tooshort++; 422 return IPPROTO_DONE; 423 } 424 #endif 425 code = icmp6->icmp6_code; 426 427 if ((sum = in6_cksum(m, IPPROTO_ICMPV6, off, icmp6len)) != 0) { 428 nd6log((LOG_ERR, 429 "ICMP6 checksum error(%d|%x) %s\n", 430 icmp6->icmp6_type, sum, 431 ip6_sprintf(ip6bufs, &ip6->ip6_src))); 432 icmp6stat.icp6s_checksum++; 433 goto freeit; 434 } 435 436 if (faithprefix_p != NULL && (*faithprefix_p)(&ip6->ip6_dst)) { 437 /* 438 * Deliver very specific ICMP6 type only. 439 * This is important to deliver TOOBIG. Otherwise PMTUD 440 * will not work. 441 */ 442 switch (icmp6->icmp6_type) { 443 case ICMP6_DST_UNREACH: 444 case ICMP6_PACKET_TOO_BIG: 445 case ICMP6_TIME_EXCEEDED: 446 break; 447 default: 448 goto freeit; 449 } 450 } 451 452 icmp6stat.icp6s_inhist[icmp6->icmp6_type]++; 453 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_msg); 454 if (icmp6->icmp6_type < ICMP6_INFOMSG_MASK) 455 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_error); 456 457 switch (icmp6->icmp6_type) { 458 case ICMP6_DST_UNREACH: 459 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_dstunreach); 460 switch (code) { 461 case ICMP6_DST_UNREACH_NOROUTE: 462 code = PRC_UNREACH_NET; 463 break; 464 case ICMP6_DST_UNREACH_ADMIN: 465 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_adminprohib); 466 code = PRC_UNREACH_PROTOCOL; /* is this a good code? */ 467 break; 468 case ICMP6_DST_UNREACH_ADDR: 469 code = PRC_HOSTDEAD; 470 break; 471 case ICMP6_DST_UNREACH_BEYONDSCOPE: 472 /* I mean "source address was incorrect." */ 473 code = PRC_PARAMPROB; 474 break; 475 case ICMP6_DST_UNREACH_NOPORT: 476 code = PRC_UNREACH_PORT; 477 break; 478 default: 479 goto badcode; 480 } 481 goto deliver; 482 break; 483 484 case ICMP6_PACKET_TOO_BIG: 485 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_pkttoobig); 486 487 /* validation is made in icmp6_mtudisc_update */ 488 489 code = PRC_MSGSIZE; 490 491 /* 492 * Updating the path MTU will be done after examining 493 * intermediate extension headers. 494 */ 495 goto deliver; 496 break; 497 498 case ICMP6_TIME_EXCEEDED: 499 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_timeexceed); 500 switch (code) { 501 case ICMP6_TIME_EXCEED_TRANSIT: 502 code = PRC_TIMXCEED_INTRANS; 503 break; 504 case ICMP6_TIME_EXCEED_REASSEMBLY: 505 code = PRC_TIMXCEED_REASS; 506 break; 507 default: 508 goto badcode; 509 } 510 goto deliver; 511 break; 512 513 case ICMP6_PARAM_PROB: 514 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_paramprob); 515 switch (code) { 516 case ICMP6_PARAMPROB_NEXTHEADER: 517 code = PRC_UNREACH_PROTOCOL; 518 break; 519 case ICMP6_PARAMPROB_HEADER: 520 case ICMP6_PARAMPROB_OPTION: 521 code = PRC_PARAMPROB; 522 break; 523 default: 524 goto badcode; 525 } 526 goto deliver; 527 break; 528 529 case ICMP6_ECHO_REQUEST: 530 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echo); 531 if (code != 0) 532 goto badcode; 533 if ((n = m_copy(m, 0, M_COPYALL)) == NULL) { 534 /* Give up remote */ 535 break; 536 } 537 if ((n->m_flags & M_EXT) != 0 538 || n->m_len < off + sizeof(struct icmp6_hdr)) { 539 struct mbuf *n0 = n; 540 const int maxlen = sizeof(*nip6) + sizeof(*nicmp6); 541 int n0len; 542 543 MGETHDR(n, M_DONTWAIT, n0->m_type); 544 n0len = n0->m_pkthdr.len; /* save for use below */ 545 if (n) 546 M_MOVE_PKTHDR(n, n0); 547 if (n && maxlen >= MHLEN) { 548 MCLGET(n, M_DONTWAIT); 549 if ((n->m_flags & M_EXT) == 0) { 550 m_free(n); 551 n = NULL; 552 } 553 } 554 if (n == NULL) { 555 /* Give up remote */ 556 m_freem(n0); 557 break; 558 } 559 /* 560 * Copy IPv6 and ICMPv6 only. 561 */ 562 nip6 = mtod(n, struct ip6_hdr *); 563 bcopy(ip6, nip6, sizeof(struct ip6_hdr)); 564 nicmp6 = (struct icmp6_hdr *)(nip6 + 1); 565 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr)); 566 noff = sizeof(struct ip6_hdr); 567 /* new mbuf contains only ipv6+icmpv6 headers */ 568 n->m_len = noff + sizeof(struct icmp6_hdr); 569 /* 570 * Adjust mbuf. ip6_plen will be adjusted in 571 * ip6_output(). 572 */ 573 m_adj(n0, off + sizeof(struct icmp6_hdr)); 574 /* recalculate complete packet size */ 575 n->m_pkthdr.len = n0len + (noff - off); 576 n->m_next = n0; 577 } else { 578 nip6 = mtod(n, struct ip6_hdr *); 579 IP6_EXTHDR_GET(nicmp6, struct icmp6_hdr *, n, off, 580 sizeof(*nicmp6)); 581 noff = off; 582 } 583 nicmp6->icmp6_type = ICMP6_ECHO_REPLY; 584 nicmp6->icmp6_code = 0; 585 if (n) { 586 icmp6stat.icp6s_reflect++; 587 icmp6stat.icp6s_outhist[ICMP6_ECHO_REPLY]++; 588 icmp6_reflect(n, noff); 589 } 590 break; 591 592 case ICMP6_ECHO_REPLY: 593 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echoreply); 594 if (code != 0) 595 goto badcode; 596 break; 597 598 case MLD_LISTENER_QUERY: 599 case MLD_LISTENER_REPORT: 600 if (icmp6len < sizeof(struct mld_hdr)) 601 goto badlen; 602 if (icmp6->icmp6_type == MLD_LISTENER_QUERY) /* XXX: ugly... */ 603 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldquery); 604 else 605 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldreport); 606 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 607 /* give up local */ 608 mld6_input(m, off); 609 m = NULL; 610 goto freeit; 611 } 612 mld6_input(n, off); 613 /* m stays. */ 614 break; 615 616 case MLD_LISTENER_DONE: 617 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mlddone); 618 if (icmp6len < sizeof(struct mld_hdr)) /* necessary? */ 619 goto badlen; 620 break; /* nothing to be done in kernel */ 621 622 case MLD_MTRACE_RESP: 623 case MLD_MTRACE: 624 /* XXX: these two are experimental. not officially defined. */ 625 /* XXX: per-interface statistics? */ 626 break; /* just pass it to applications */ 627 628 case ICMP6_WRUREQUEST: /* ICMP6_FQDN_QUERY */ 629 { 630 enum { WRU, FQDN } mode; 631 632 if (!icmp6_nodeinfo) 633 break; 634 635 if (icmp6len == sizeof(struct icmp6_hdr) + 4) 636 mode = WRU; 637 else if (icmp6len >= sizeof(struct icmp6_nodeinfo)) 638 mode = FQDN; 639 else 640 goto badlen; 641 642 #define hostnamelen strlen(hostname) 643 if (mode == FQDN) { 644 #ifndef PULLDOWN_TEST 645 IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_nodeinfo), 646 IPPROTO_DONE); 647 #endif 648 n = m_copy(m, 0, M_COPYALL); 649 if (n) 650 n = ni6_input(n, off); 651 /* XXX meaningless if n == NULL */ 652 noff = sizeof(struct ip6_hdr); 653 } else { 654 u_char *p; 655 int maxlen, maxhlen; 656 657 /* 658 * XXX: this combination of flags is pointless, 659 * but should we keep this for compatibility? 660 */ 661 if ((icmp6_nodeinfo & 5) != 5) 662 break; 663 664 if (code != 0) 665 goto badcode; 666 maxlen = sizeof(*nip6) + sizeof(*nicmp6) + 4; 667 if (maxlen >= MCLBYTES) { 668 /* Give up remote */ 669 break; 670 } 671 MGETHDR(n, M_DONTWAIT, m->m_type); 672 if (n && maxlen > MHLEN) { 673 MCLGET(n, M_DONTWAIT); 674 if ((n->m_flags & M_EXT) == 0) { 675 m_free(n); 676 n = NULL; 677 } 678 } 679 if (n && !m_dup_pkthdr(n, m, M_DONTWAIT)) { 680 /* 681 * Previous code did a blind M_COPY_PKTHDR 682 * and said "just for rcvif". If true, then 683 * we could tolerate the dup failing (due to 684 * the deep copy of the tag chain). For now 685 * be conservative and just fail. 686 */ 687 m_free(n); 688 n = NULL; 689 } 690 if (n == NULL) { 691 /* Give up remote */ 692 break; 693 } 694 n->m_pkthdr.rcvif = NULL; 695 n->m_len = 0; 696 maxhlen = M_TRAILINGSPACE(n) - maxlen; 697 if (maxhlen > hostnamelen) 698 maxhlen = hostnamelen; 699 /* 700 * Copy IPv6 and ICMPv6 only. 701 */ 702 nip6 = mtod(n, struct ip6_hdr *); 703 bcopy(ip6, nip6, sizeof(struct ip6_hdr)); 704 nicmp6 = (struct icmp6_hdr *)(nip6 + 1); 705 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr)); 706 p = (u_char *)(nicmp6 + 1); 707 bzero(p, 4); 708 bcopy(hostname, p + 4, maxhlen); /* meaningless TTL */ 709 noff = sizeof(struct ip6_hdr); 710 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) + 711 sizeof(struct icmp6_hdr) + 4 + maxhlen; 712 nicmp6->icmp6_type = ICMP6_WRUREPLY; 713 nicmp6->icmp6_code = 0; 714 } 715 #undef hostnamelen 716 if (n) { 717 icmp6stat.icp6s_reflect++; 718 icmp6stat.icp6s_outhist[ICMP6_WRUREPLY]++; 719 icmp6_reflect(n, noff); 720 } 721 break; 722 } 723 724 case ICMP6_WRUREPLY: 725 if (code != 0) 726 goto badcode; 727 break; 728 729 case ND_ROUTER_SOLICIT: 730 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routersolicit); 731 if (code != 0) 732 goto badcode; 733 if (icmp6len < sizeof(struct nd_router_solicit)) 734 goto badlen; 735 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 736 /* give up local */ 737 nd6_rs_input(m, off, icmp6len); 738 m = NULL; 739 goto freeit; 740 } 741 nd6_rs_input(n, off, icmp6len); 742 /* m stays. */ 743 break; 744 745 case ND_ROUTER_ADVERT: 746 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routeradvert); 747 if (code != 0) 748 goto badcode; 749 if (icmp6len < sizeof(struct nd_router_advert)) 750 goto badlen; 751 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 752 /* give up local */ 753 nd6_ra_input(m, off, icmp6len); 754 m = NULL; 755 goto freeit; 756 } 757 nd6_ra_input(n, off, icmp6len); 758 /* m stays. */ 759 break; 760 761 case ND_NEIGHBOR_SOLICIT: 762 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighborsolicit); 763 if (code != 0) 764 goto badcode; 765 if (icmp6len < sizeof(struct nd_neighbor_solicit)) 766 goto badlen; 767 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 768 /* give up local */ 769 nd6_ns_input(m, off, icmp6len); 770 m = NULL; 771 goto freeit; 772 } 773 nd6_ns_input(n, off, icmp6len); 774 /* m stays. */ 775 break; 776 777 case ND_NEIGHBOR_ADVERT: 778 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighboradvert); 779 if (code != 0) 780 goto badcode; 781 if (icmp6len < sizeof(struct nd_neighbor_advert)) 782 goto badlen; 783 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 784 /* give up local */ 785 nd6_na_input(m, off, icmp6len); 786 m = NULL; 787 goto freeit; 788 } 789 nd6_na_input(n, off, icmp6len); 790 /* m stays. */ 791 break; 792 793 case ND_REDIRECT: 794 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_redirect); 795 if (code != 0) 796 goto badcode; 797 if (icmp6len < sizeof(struct nd_redirect)) 798 goto badlen; 799 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 800 /* give up local */ 801 icmp6_redirect_input(m, off); 802 m = NULL; 803 goto freeit; 804 } 805 icmp6_redirect_input(n, off); 806 /* m stays. */ 807 break; 808 809 case ICMP6_ROUTER_RENUMBERING: 810 if (code != ICMP6_ROUTER_RENUMBERING_COMMAND && 811 code != ICMP6_ROUTER_RENUMBERING_RESULT) 812 goto badcode; 813 if (icmp6len < sizeof(struct icmp6_router_renum)) 814 goto badlen; 815 break; 816 817 default: 818 nd6log((LOG_DEBUG, 819 "icmp6_input: unknown type %d(src=%s, dst=%s, ifid=%d)\n", 820 icmp6->icmp6_type, ip6_sprintf(ip6bufs, &ip6->ip6_src), 821 ip6_sprintf(ip6bufd, &ip6->ip6_dst), 822 m->m_pkthdr.rcvif ? m->m_pkthdr.rcvif->if_index : 0)); 823 if (icmp6->icmp6_type < ICMP6_ECHO_REQUEST) { 824 /* ICMPv6 error: MUST deliver it by spec... */ 825 code = PRC_NCMDS; 826 /* deliver */ 827 } else { 828 /* ICMPv6 informational: MUST not deliver */ 829 break; 830 } 831 deliver: 832 if (icmp6_notify_error(&m, off, icmp6len, code)) { 833 /* In this case, m should've been freed. */ 834 return (IPPROTO_DONE); 835 } 836 break; 837 838 badcode: 839 icmp6stat.icp6s_badcode++; 840 break; 841 842 badlen: 843 icmp6stat.icp6s_badlen++; 844 break; 845 } 846 847 /* deliver the packet to appropriate sockets */ 848 icmp6_rip6_input(&m, *offp); 849 850 return IPPROTO_DONE; 851 852 freeit: 853 m_freem(m); 854 return IPPROTO_DONE; 855 } 856 857 static int 858 icmp6_notify_error(struct mbuf **mp, int off, int icmp6len, int code) 859 { 860 struct mbuf *m = *mp; 861 struct icmp6_hdr *icmp6; 862 struct ip6_hdr *eip6; 863 u_int32_t notifymtu; 864 struct sockaddr_in6 icmp6src, icmp6dst; 865 866 if (icmp6len < sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr)) { 867 icmp6stat.icp6s_tooshort++; 868 goto freeit; 869 } 870 #ifndef PULLDOWN_TEST 871 IP6_EXTHDR_CHECK(m, off, 872 sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr), -1); 873 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 874 #else 875 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, 876 sizeof(*icmp6) + sizeof(struct ip6_hdr)); 877 if (icmp6 == NULL) { 878 icmp6stat.icp6s_tooshort++; 879 return (-1); 880 } 881 #endif 882 eip6 = (struct ip6_hdr *)(icmp6 + 1); 883 884 /* Detect the upper level protocol */ 885 { 886 void (*ctlfunc) __P((int, struct sockaddr *, void *)); 887 u_int8_t nxt = eip6->ip6_nxt; 888 int eoff = off + sizeof(struct icmp6_hdr) + 889 sizeof(struct ip6_hdr); 890 struct ip6ctlparam ip6cp; 891 struct in6_addr *finaldst = NULL; 892 int icmp6type = icmp6->icmp6_type; 893 struct ip6_frag *fh; 894 struct ip6_rthdr *rth; 895 struct ip6_rthdr0 *rth0; 896 int rthlen; 897 898 while (1) { /* XXX: should avoid infinite loop explicitly? */ 899 struct ip6_ext *eh; 900 901 switch (nxt) { 902 case IPPROTO_HOPOPTS: 903 case IPPROTO_DSTOPTS: 904 case IPPROTO_AH: 905 #ifndef PULLDOWN_TEST 906 IP6_EXTHDR_CHECK(m, 0, 907 eoff + sizeof(struct ip6_ext), -1); 908 eh = (struct ip6_ext *)(mtod(m, caddr_t) + eoff); 909 #else 910 IP6_EXTHDR_GET(eh, struct ip6_ext *, m, 911 eoff, sizeof(*eh)); 912 if (eh == NULL) { 913 icmp6stat.icp6s_tooshort++; 914 return (-1); 915 } 916 #endif 917 918 if (nxt == IPPROTO_AH) 919 eoff += (eh->ip6e_len + 2) << 2; 920 else 921 eoff += (eh->ip6e_len + 1) << 3; 922 nxt = eh->ip6e_nxt; 923 break; 924 case IPPROTO_ROUTING: 925 /* 926 * When the erroneous packet contains a 927 * routing header, we should examine the 928 * header to determine the final destination. 929 * Otherwise, we can't properly update 930 * information that depends on the final 931 * destination (e.g. path MTU). 932 */ 933 #ifndef PULLDOWN_TEST 934 IP6_EXTHDR_CHECK(m, 0, eoff + sizeof(*rth), -1); 935 rth = (struct ip6_rthdr *) 936 (mtod(m, caddr_t) + eoff); 937 #else 938 IP6_EXTHDR_GET(rth, struct ip6_rthdr *, m, 939 eoff, sizeof(*rth)); 940 if (rth == NULL) { 941 icmp6stat.icp6s_tooshort++; 942 return (-1); 943 } 944 #endif 945 rthlen = (rth->ip6r_len + 1) << 3; 946 /* 947 * XXX: currently there is no 948 * officially defined type other 949 * than type-0. 950 * Note that if the segment left field 951 * is 0, all intermediate hops must 952 * have been passed. 953 */ 954 if (rth->ip6r_segleft && 955 rth->ip6r_type == IPV6_RTHDR_TYPE_0) { 956 int hops; 957 958 #ifndef PULLDOWN_TEST 959 IP6_EXTHDR_CHECK(m, 0, eoff + rthlen, -1); 960 rth0 = (struct ip6_rthdr0 *) 961 (mtod(m, caddr_t) + eoff); 962 #else 963 IP6_EXTHDR_GET(rth0, 964 struct ip6_rthdr0 *, m, 965 eoff, rthlen); 966 if (rth0 == NULL) { 967 icmp6stat.icp6s_tooshort++; 968 return (-1); 969 } 970 #endif 971 /* just ignore a bogus header */ 972 if ((rth0->ip6r0_len % 2) == 0 && 973 (hops = rth0->ip6r0_len/2)) 974 finaldst = (struct in6_addr *)(rth0 + 1) + (hops - 1); 975 } 976 eoff += rthlen; 977 nxt = rth->ip6r_nxt; 978 break; 979 case IPPROTO_FRAGMENT: 980 #ifndef PULLDOWN_TEST 981 IP6_EXTHDR_CHECK(m, 0, eoff + 982 sizeof(struct ip6_frag), -1); 983 fh = (struct ip6_frag *)(mtod(m, caddr_t) + 984 eoff); 985 #else 986 IP6_EXTHDR_GET(fh, struct ip6_frag *, m, 987 eoff, sizeof(*fh)); 988 if (fh == NULL) { 989 icmp6stat.icp6s_tooshort++; 990 return (-1); 991 } 992 #endif 993 /* 994 * Data after a fragment header is meaningless 995 * unless it is the first fragment, but 996 * we'll go to the notify label for path MTU 997 * discovery. 998 */ 999 if (fh->ip6f_offlg & IP6F_OFF_MASK) 1000 goto notify; 1001 1002 eoff += sizeof(struct ip6_frag); 1003 nxt = fh->ip6f_nxt; 1004 break; 1005 default: 1006 /* 1007 * This case includes ESP and the No Next 1008 * Header. In such cases going to the notify 1009 * label does not have any meaning 1010 * (i.e. ctlfunc will be NULL), but we go 1011 * anyway since we might have to update 1012 * path MTU information. 1013 */ 1014 goto notify; 1015 } 1016 } 1017 notify: 1018 #ifndef PULLDOWN_TEST 1019 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 1020 #else 1021 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, 1022 sizeof(*icmp6) + sizeof(struct ip6_hdr)); 1023 if (icmp6 == NULL) { 1024 icmp6stat.icp6s_tooshort++; 1025 return (-1); 1026 } 1027 #endif 1028 1029 /* 1030 * retrieve parameters from the inner IPv6 header, and convert 1031 * them into sockaddr structures. 1032 * XXX: there is no guarantee that the source or destination 1033 * addresses of the inner packet are in the same scope as 1034 * the addresses of the icmp packet. But there is no other 1035 * way to determine the zone. 1036 */ 1037 eip6 = (struct ip6_hdr *)(icmp6 + 1); 1038 1039 bzero(&icmp6dst, sizeof(icmp6dst)); 1040 icmp6dst.sin6_len = sizeof(struct sockaddr_in6); 1041 icmp6dst.sin6_family = AF_INET6; 1042 if (finaldst == NULL) 1043 icmp6dst.sin6_addr = eip6->ip6_dst; 1044 else 1045 icmp6dst.sin6_addr = *finaldst; 1046 if (in6_setscope(&icmp6dst.sin6_addr, m->m_pkthdr.rcvif, NULL)) 1047 goto freeit; 1048 bzero(&icmp6src, sizeof(icmp6src)); 1049 icmp6src.sin6_len = sizeof(struct sockaddr_in6); 1050 icmp6src.sin6_family = AF_INET6; 1051 icmp6src.sin6_addr = eip6->ip6_src; 1052 if (in6_setscope(&icmp6src.sin6_addr, m->m_pkthdr.rcvif, NULL)) 1053 goto freeit; 1054 icmp6src.sin6_flowinfo = 1055 (eip6->ip6_flow & IPV6_FLOWLABEL_MASK); 1056 1057 if (finaldst == NULL) 1058 finaldst = &eip6->ip6_dst; 1059 ip6cp.ip6c_m = m; 1060 ip6cp.ip6c_icmp6 = icmp6; 1061 ip6cp.ip6c_ip6 = (struct ip6_hdr *)(icmp6 + 1); 1062 ip6cp.ip6c_off = eoff; 1063 ip6cp.ip6c_finaldst = finaldst; 1064 ip6cp.ip6c_src = &icmp6src; 1065 ip6cp.ip6c_nxt = nxt; 1066 1067 if (icmp6type == ICMP6_PACKET_TOO_BIG) { 1068 notifymtu = ntohl(icmp6->icmp6_mtu); 1069 ip6cp.ip6c_cmdarg = (void *)¬ifymtu; 1070 icmp6_mtudisc_update(&ip6cp, 1); /*XXX*/ 1071 } 1072 1073 ctlfunc = (void (*) __P((int, struct sockaddr *, void *))) 1074 (inet6sw[ip6_protox[nxt]].pr_ctlinput); 1075 if (ctlfunc) { 1076 (void) (*ctlfunc)(code, (struct sockaddr *)&icmp6dst, 1077 &ip6cp); 1078 } 1079 } 1080 *mp = m; 1081 return (0); 1082 1083 freeit: 1084 m_freem(m); 1085 return (-1); 1086 } 1087 1088 void 1089 icmp6_mtudisc_update(struct ip6ctlparam *ip6cp, int validated) 1090 { 1091 struct in6_addr *dst = ip6cp->ip6c_finaldst; 1092 struct icmp6_hdr *icmp6 = ip6cp->ip6c_icmp6; 1093 struct mbuf *m = ip6cp->ip6c_m; /* will be necessary for scope issue */ 1094 u_int mtu = ntohl(icmp6->icmp6_mtu); 1095 struct in_conninfo inc; 1096 1097 #if 0 1098 /* 1099 * RFC2460 section 5, last paragraph. 1100 * even though minimum link MTU for IPv6 is IPV6_MMTU, 1101 * we may see ICMPv6 too big with mtu < IPV6_MMTU 1102 * due to packet translator in the middle. 1103 * see ip6_output() and ip6_getpmtu() "alwaysfrag" case for 1104 * special handling. 1105 */ 1106 if (mtu < IPV6_MMTU) 1107 return; 1108 #endif 1109 1110 /* 1111 * we reject ICMPv6 too big with abnormally small value. 1112 * XXX what is the good definition of "abnormally small"? 1113 */ 1114 if (mtu < sizeof(struct ip6_hdr) + sizeof(struct ip6_frag) + 8) 1115 return; 1116 1117 if (!validated) 1118 return; 1119 1120 bzero(&inc, sizeof(inc)); 1121 inc.inc_flags = 1; /* IPv6 */ 1122 inc.inc6_faddr = *dst; 1123 if (in6_setscope(&inc.inc6_faddr, m->m_pkthdr.rcvif, NULL)) 1124 return; 1125 1126 if (mtu < tcp_maxmtu6(&inc, NULL)) { 1127 tcp_hc_updatemtu(&inc, mtu); 1128 icmp6stat.icp6s_pmtuchg++; 1129 } 1130 } 1131 1132 /* 1133 * Process a Node Information Query packet, based on 1134 * draft-ietf-ipngwg-icmp-name-lookups-07. 1135 * 1136 * Spec incompatibilities: 1137 * - IPv6 Subject address handling 1138 * - IPv4 Subject address handling support missing 1139 * - Proxy reply (answer even if it's not for me) 1140 * - joins NI group address at in6_ifattach() time only, does not cope 1141 * with hostname changes by sethostname(3) 1142 */ 1143 #define hostnamelen strlen(hostname) 1144 static struct mbuf * 1145 ni6_input(struct mbuf *m, int off) 1146 { 1147 struct icmp6_nodeinfo *ni6, *nni6; 1148 struct mbuf *n = NULL; 1149 u_int16_t qtype; 1150 int subjlen; 1151 int replylen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo); 1152 struct ni_reply_fqdn *fqdn; 1153 int addrs; /* for NI_QTYPE_NODEADDR */ 1154 struct ifnet *ifp = NULL; /* for NI_QTYPE_NODEADDR */ 1155 struct in6_addr in6_subj; /* subject address */ 1156 struct ip6_hdr *ip6; 1157 int oldfqdn = 0; /* if 1, return pascal string (03 draft) */ 1158 char *subj = NULL; 1159 struct in6_ifaddr *ia6 = NULL; 1160 1161 ip6 = mtod(m, struct ip6_hdr *); 1162 #ifndef PULLDOWN_TEST 1163 ni6 = (struct icmp6_nodeinfo *)(mtod(m, caddr_t) + off); 1164 #else 1165 IP6_EXTHDR_GET(ni6, struct icmp6_nodeinfo *, m, off, sizeof(*ni6)); 1166 if (ni6 == NULL) { 1167 /* m is already reclaimed */ 1168 return (NULL); 1169 } 1170 #endif 1171 1172 /* 1173 * Validate IPv6 source address. 1174 * The default configuration MUST be to refuse answering queries from 1175 * global-scope addresses according to RFC4602. 1176 * Notes: 1177 * - it's not very clear what "refuse" means; this implementation 1178 * simply drops it. 1179 * - it's not very easy to identify global-scope (unicast) addresses 1180 * since there are many prefixes for them. It should be safer 1181 * and in practice sufficient to check "all" but loopback and 1182 * link-local (note that site-local unicast was deprecated and 1183 * ULA is defined as global scope-wise) 1184 */ 1185 if ((icmp6_nodeinfo & ICMP6_NODEINFO_GLOBALOK) == 0 && 1186 !IN6_IS_ADDR_LOOPBACK(&ip6->ip6_src) && 1187 !IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_src)) 1188 goto bad; 1189 1190 /* 1191 * Validate IPv6 destination address. 1192 * 1193 * The Responder must discard the Query without further processing 1194 * unless it is one of the Responder's unicast or anycast addresses, or 1195 * a link-local scope multicast address which the Responder has joined. 1196 * [RFC4602, Section 5.] 1197 */ 1198 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 1199 if (!IN6_IS_ADDR_MC_LINKLOCAL(&ip6->ip6_dst)) 1200 goto bad; 1201 /* else it's a link-local multicast, fine */ 1202 } else { /* unicast or anycast */ 1203 if ((ia6 = ip6_getdstifaddr(m)) == NULL) 1204 goto bad; /* XXX impossible */ 1205 1206 if ((ia6->ia6_flags & IN6_IFF_TEMPORARY) && 1207 !(icmp6_nodeinfo & ICMP6_NODEINFO_TMPADDROK)) { 1208 nd6log((LOG_DEBUG, "ni6_input: ignore node info to " 1209 "a temporary address in %s:%d", 1210 __FILE__, __LINE__)); 1211 goto bad; 1212 } 1213 } 1214 1215 /* validate query Subject field. */ 1216 qtype = ntohs(ni6->ni_qtype); 1217 subjlen = m->m_pkthdr.len - off - sizeof(struct icmp6_nodeinfo); 1218 switch (qtype) { 1219 case NI_QTYPE_NOOP: 1220 case NI_QTYPE_SUPTYPES: 1221 /* 07 draft */ 1222 if (ni6->ni_code == ICMP6_NI_SUBJ_FQDN && subjlen == 0) 1223 break; 1224 /* FALLTHROUGH */ 1225 case NI_QTYPE_FQDN: 1226 case NI_QTYPE_NODEADDR: 1227 case NI_QTYPE_IPV4ADDR: 1228 switch (ni6->ni_code) { 1229 case ICMP6_NI_SUBJ_IPV6: 1230 #if ICMP6_NI_SUBJ_IPV6 != 0 1231 case 0: 1232 #endif 1233 /* 1234 * backward compatibility - try to accept 03 draft 1235 * format, where no Subject is present. 1236 */ 1237 if (qtype == NI_QTYPE_FQDN && ni6->ni_code == 0 && 1238 subjlen == 0) { 1239 oldfqdn++; 1240 break; 1241 } 1242 #if ICMP6_NI_SUBJ_IPV6 != 0 1243 if (ni6->ni_code != ICMP6_NI_SUBJ_IPV6) 1244 goto bad; 1245 #endif 1246 1247 if (subjlen != sizeof(struct in6_addr)) 1248 goto bad; 1249 1250 /* 1251 * Validate Subject address. 1252 * 1253 * Not sure what exactly "address belongs to the node" 1254 * means in the spec, is it just unicast, or what? 1255 * 1256 * At this moment we consider Subject address as 1257 * "belong to the node" if the Subject address equals 1258 * to the IPv6 destination address; validation for 1259 * IPv6 destination address should have done enough 1260 * check for us. 1261 * 1262 * We do not do proxy at this moment. 1263 */ 1264 /* m_pulldown instead of copy? */ 1265 m_copydata(m, off + sizeof(struct icmp6_nodeinfo), 1266 subjlen, (caddr_t)&in6_subj); 1267 if (in6_setscope(&in6_subj, m->m_pkthdr.rcvif, NULL)) 1268 goto bad; 1269 1270 subj = (char *)&in6_subj; 1271 if (IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, &in6_subj)) 1272 break; 1273 1274 /* 1275 * XXX if we are to allow other cases, we should really 1276 * be careful about scope here. 1277 * basically, we should disallow queries toward IPv6 1278 * destination X with subject Y, 1279 * if scope(X) > scope(Y). 1280 * if we allow scope(X) > scope(Y), it will result in 1281 * information leakage across scope boundary. 1282 */ 1283 goto bad; 1284 1285 case ICMP6_NI_SUBJ_FQDN: 1286 /* 1287 * Validate Subject name with gethostname(3). 1288 * 1289 * The behavior may need some debate, since: 1290 * - we are not sure if the node has FQDN as 1291 * hostname (returned by gethostname(3)). 1292 * - the code does wildcard match for truncated names. 1293 * however, we are not sure if we want to perform 1294 * wildcard match, if gethostname(3) side has 1295 * truncated hostname. 1296 */ 1297 n = ni6_nametodns(hostname, hostnamelen, 0); 1298 if (!n || n->m_next || n->m_len == 0) 1299 goto bad; 1300 IP6_EXTHDR_GET(subj, char *, m, 1301 off + sizeof(struct icmp6_nodeinfo), subjlen); 1302 if (subj == NULL) 1303 goto bad; 1304 if (!ni6_dnsmatch(subj, subjlen, mtod(n, const char *), 1305 n->m_len)) { 1306 goto bad; 1307 } 1308 m_freem(n); 1309 n = NULL; 1310 break; 1311 1312 case ICMP6_NI_SUBJ_IPV4: /* XXX: to be implemented? */ 1313 default: 1314 goto bad; 1315 } 1316 break; 1317 } 1318 1319 /* refuse based on configuration. XXX ICMP6_NI_REFUSED? */ 1320 switch (qtype) { 1321 case NI_QTYPE_FQDN: 1322 if ((icmp6_nodeinfo & ICMP6_NODEINFO_FQDNOK) == 0) 1323 goto bad; 1324 break; 1325 case NI_QTYPE_NODEADDR: 1326 case NI_QTYPE_IPV4ADDR: 1327 if ((icmp6_nodeinfo & ICMP6_NODEINFO_NODEADDROK) == 0) 1328 goto bad; 1329 break; 1330 } 1331 1332 /* guess reply length */ 1333 switch (qtype) { 1334 case NI_QTYPE_NOOP: 1335 break; /* no reply data */ 1336 case NI_QTYPE_SUPTYPES: 1337 replylen += sizeof(u_int32_t); 1338 break; 1339 case NI_QTYPE_FQDN: 1340 /* XXX will append an mbuf */ 1341 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1342 break; 1343 case NI_QTYPE_NODEADDR: 1344 addrs = ni6_addrs(ni6, m, &ifp, (struct in6_addr *)subj); 1345 if ((replylen += addrs * (sizeof(struct in6_addr) + 1346 sizeof(u_int32_t))) > MCLBYTES) 1347 replylen = MCLBYTES; /* XXX: will truncate pkt later */ 1348 break; 1349 case NI_QTYPE_IPV4ADDR: 1350 /* unsupported - should respond with unknown Qtype? */ 1351 break; 1352 default: 1353 /* 1354 * XXX: We must return a reply with the ICMP6 code 1355 * `unknown Qtype' in this case. However we regard the case 1356 * as an FQDN query for backward compatibility. 1357 * Older versions set a random value to this field, 1358 * so it rarely varies in the defined qtypes. 1359 * But the mechanism is not reliable... 1360 * maybe we should obsolete older versions. 1361 */ 1362 qtype = NI_QTYPE_FQDN; 1363 /* XXX will append an mbuf */ 1364 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1365 oldfqdn++; 1366 break; 1367 } 1368 1369 /* allocate an mbuf to reply. */ 1370 MGETHDR(n, M_DONTWAIT, m->m_type); 1371 if (n == NULL) { 1372 m_freem(m); 1373 return (NULL); 1374 } 1375 M_MOVE_PKTHDR(n, m); /* just for recvif */ 1376 if (replylen > MHLEN) { 1377 if (replylen > MCLBYTES) { 1378 /* 1379 * XXX: should we try to allocate more? But MCLBYTES 1380 * is probably much larger than IPV6_MMTU... 1381 */ 1382 goto bad; 1383 } 1384 MCLGET(n, M_DONTWAIT); 1385 if ((n->m_flags & M_EXT) == 0) { 1386 goto bad; 1387 } 1388 } 1389 n->m_pkthdr.len = n->m_len = replylen; 1390 1391 /* copy mbuf header and IPv6 + Node Information base headers */ 1392 bcopy(mtod(m, caddr_t), mtod(n, caddr_t), sizeof(struct ip6_hdr)); 1393 nni6 = (struct icmp6_nodeinfo *)(mtod(n, struct ip6_hdr *) + 1); 1394 bcopy((caddr_t)ni6, (caddr_t)nni6, sizeof(struct icmp6_nodeinfo)); 1395 1396 /* qtype dependent procedure */ 1397 switch (qtype) { 1398 case NI_QTYPE_NOOP: 1399 nni6->ni_code = ICMP6_NI_SUCCESS; 1400 nni6->ni_flags = 0; 1401 break; 1402 case NI_QTYPE_SUPTYPES: 1403 { 1404 u_int32_t v; 1405 nni6->ni_code = ICMP6_NI_SUCCESS; 1406 nni6->ni_flags = htons(0x0000); /* raw bitmap */ 1407 /* supports NOOP, SUPTYPES, FQDN, and NODEADDR */ 1408 v = (u_int32_t)htonl(0x0000000f); 1409 bcopy(&v, nni6 + 1, sizeof(u_int32_t)); 1410 break; 1411 } 1412 case NI_QTYPE_FQDN: 1413 nni6->ni_code = ICMP6_NI_SUCCESS; 1414 fqdn = (struct ni_reply_fqdn *)(mtod(n, caddr_t) + 1415 sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo)); 1416 nni6->ni_flags = 0; /* XXX: meaningless TTL */ 1417 fqdn->ni_fqdn_ttl = 0; /* ditto. */ 1418 /* 1419 * XXX do we really have FQDN in variable "hostname"? 1420 */ 1421 n->m_next = ni6_nametodns(hostname, hostnamelen, oldfqdn); 1422 if (n->m_next == NULL) 1423 goto bad; 1424 /* XXX we assume that n->m_next is not a chain */ 1425 if (n->m_next->m_next != NULL) 1426 goto bad; 1427 n->m_pkthdr.len += n->m_next->m_len; 1428 break; 1429 case NI_QTYPE_NODEADDR: 1430 { 1431 int lenlim, copied; 1432 1433 nni6->ni_code = ICMP6_NI_SUCCESS; 1434 n->m_pkthdr.len = n->m_len = 1435 sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo); 1436 lenlim = M_TRAILINGSPACE(n); 1437 copied = ni6_store_addrs(ni6, nni6, ifp, lenlim); 1438 /* XXX: reset mbuf length */ 1439 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) + 1440 sizeof(struct icmp6_nodeinfo) + copied; 1441 break; 1442 } 1443 default: 1444 break; /* XXX impossible! */ 1445 } 1446 1447 nni6->ni_type = ICMP6_NI_REPLY; 1448 m_freem(m); 1449 return (n); 1450 1451 bad: 1452 m_freem(m); 1453 if (n) 1454 m_freem(n); 1455 return (NULL); 1456 } 1457 #undef hostnamelen 1458 1459 /* 1460 * make a mbuf with DNS-encoded string. no compression support. 1461 * 1462 * XXX names with less than 2 dots (like "foo" or "foo.section") will be 1463 * treated as truncated name (two \0 at the end). this is a wild guess. 1464 * 1465 * old - return pascal string if non-zero 1466 */ 1467 static struct mbuf * 1468 ni6_nametodns(const char *name, int namelen, int old) 1469 { 1470 struct mbuf *m; 1471 char *cp, *ep; 1472 const char *p, *q; 1473 int i, len, nterm; 1474 1475 if (old) 1476 len = namelen + 1; 1477 else 1478 len = MCLBYTES; 1479 1480 /* because MAXHOSTNAMELEN is usually 256, we use cluster mbuf */ 1481 MGET(m, M_DONTWAIT, MT_DATA); 1482 if (m && len > MLEN) { 1483 MCLGET(m, M_DONTWAIT); 1484 if ((m->m_flags & M_EXT) == 0) 1485 goto fail; 1486 } 1487 if (!m) 1488 goto fail; 1489 m->m_next = NULL; 1490 1491 if (old) { 1492 m->m_len = len; 1493 *mtod(m, char *) = namelen; 1494 bcopy(name, mtod(m, char *) + 1, namelen); 1495 return m; 1496 } else { 1497 m->m_len = 0; 1498 cp = mtod(m, char *); 1499 ep = mtod(m, char *) + M_TRAILINGSPACE(m); 1500 1501 /* if not certain about my name, return empty buffer */ 1502 if (namelen == 0) 1503 return m; 1504 1505 /* 1506 * guess if it looks like shortened hostname, or FQDN. 1507 * shortened hostname needs two trailing "\0". 1508 */ 1509 i = 0; 1510 for (p = name; p < name + namelen; p++) { 1511 if (*p && *p == '.') 1512 i++; 1513 } 1514 if (i < 2) 1515 nterm = 2; 1516 else 1517 nterm = 1; 1518 1519 p = name; 1520 while (cp < ep && p < name + namelen) { 1521 i = 0; 1522 for (q = p; q < name + namelen && *q && *q != '.'; q++) 1523 i++; 1524 /* result does not fit into mbuf */ 1525 if (cp + i + 1 >= ep) 1526 goto fail; 1527 /* 1528 * DNS label length restriction, RFC1035 page 8. 1529 * "i == 0" case is included here to avoid returning 1530 * 0-length label on "foo..bar". 1531 */ 1532 if (i <= 0 || i >= 64) 1533 goto fail; 1534 *cp++ = i; 1535 bcopy(p, cp, i); 1536 cp += i; 1537 p = q; 1538 if (p < name + namelen && *p == '.') 1539 p++; 1540 } 1541 /* termination */ 1542 if (cp + nterm >= ep) 1543 goto fail; 1544 while (nterm-- > 0) 1545 *cp++ = '\0'; 1546 m->m_len = cp - mtod(m, char *); 1547 return m; 1548 } 1549 1550 panic("should not reach here"); 1551 /* NOTREACHED */ 1552 1553 fail: 1554 if (m) 1555 m_freem(m); 1556 return NULL; 1557 } 1558 1559 /* 1560 * check if two DNS-encoded string matches. takes care of truncated 1561 * form (with \0\0 at the end). no compression support. 1562 * XXX upper/lowercase match (see RFC2065) 1563 */ 1564 static int 1565 ni6_dnsmatch(const char *a, int alen, const char *b, int blen) 1566 { 1567 const char *a0, *b0; 1568 int l; 1569 1570 /* simplest case - need validation? */ 1571 if (alen == blen && bcmp(a, b, alen) == 0) 1572 return 1; 1573 1574 a0 = a; 1575 b0 = b; 1576 1577 /* termination is mandatory */ 1578 if (alen < 2 || blen < 2) 1579 return 0; 1580 if (a0[alen - 1] != '\0' || b0[blen - 1] != '\0') 1581 return 0; 1582 alen--; 1583 blen--; 1584 1585 while (a - a0 < alen && b - b0 < blen) { 1586 if (a - a0 + 1 > alen || b - b0 + 1 > blen) 1587 return 0; 1588 1589 if ((signed char)a[0] < 0 || (signed char)b[0] < 0) 1590 return 0; 1591 /* we don't support compression yet */ 1592 if (a[0] >= 64 || b[0] >= 64) 1593 return 0; 1594 1595 /* truncated case */ 1596 if (a[0] == 0 && a - a0 == alen - 1) 1597 return 1; 1598 if (b[0] == 0 && b - b0 == blen - 1) 1599 return 1; 1600 if (a[0] == 0 || b[0] == 0) 1601 return 0; 1602 1603 if (a[0] != b[0]) 1604 return 0; 1605 l = a[0]; 1606 if (a - a0 + 1 + l > alen || b - b0 + 1 + l > blen) 1607 return 0; 1608 if (bcmp(a + 1, b + 1, l) != 0) 1609 return 0; 1610 1611 a += 1 + l; 1612 b += 1 + l; 1613 } 1614 1615 if (a - a0 == alen && b - b0 == blen) 1616 return 1; 1617 else 1618 return 0; 1619 } 1620 1621 /* 1622 * calculate the number of addresses to be returned in the node info reply. 1623 */ 1624 static int 1625 ni6_addrs(struct icmp6_nodeinfo *ni6, struct mbuf *m, struct ifnet **ifpp, 1626 struct in6_addr *subj) 1627 { 1628 struct ifnet *ifp; 1629 struct in6_ifaddr *ifa6; 1630 struct ifaddr *ifa; 1631 int addrs = 0, addrsofif, iffound = 0; 1632 int niflags = ni6->ni_flags; 1633 1634 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0) { 1635 switch (ni6->ni_code) { 1636 case ICMP6_NI_SUBJ_IPV6: 1637 if (subj == NULL) /* must be impossible... */ 1638 return (0); 1639 break; 1640 default: 1641 /* 1642 * XXX: we only support IPv6 subject address for 1643 * this Qtype. 1644 */ 1645 return (0); 1646 } 1647 } 1648 1649 IFNET_RLOCK(); 1650 for (ifp = TAILQ_FIRST(&ifnet); ifp; ifp = TAILQ_NEXT(ifp, if_list)) { 1651 addrsofif = 0; 1652 TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list) { 1653 if (ifa->ifa_addr->sa_family != AF_INET6) 1654 continue; 1655 ifa6 = (struct in6_ifaddr *)ifa; 1656 1657 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0 && 1658 IN6_ARE_ADDR_EQUAL(subj, &ifa6->ia_addr.sin6_addr)) 1659 iffound = 1; 1660 1661 /* 1662 * IPv4-mapped addresses can only be returned by a 1663 * Node Information proxy, since they represent 1664 * addresses of IPv4-only nodes, which perforce do 1665 * not implement this protocol. 1666 * [icmp-name-lookups-07, Section 5.4] 1667 * So we don't support NI_NODEADDR_FLAG_COMPAT in 1668 * this function at this moment. 1669 */ 1670 1671 /* What do we have to do about ::1? */ 1672 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1673 case IPV6_ADDR_SCOPE_LINKLOCAL: 1674 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0) 1675 continue; 1676 break; 1677 case IPV6_ADDR_SCOPE_SITELOCAL: 1678 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0) 1679 continue; 1680 break; 1681 case IPV6_ADDR_SCOPE_GLOBAL: 1682 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0) 1683 continue; 1684 break; 1685 default: 1686 continue; 1687 } 1688 1689 /* 1690 * check if anycast is okay. 1691 * XXX: just experimental. not in the spec. 1692 */ 1693 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 && 1694 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0) 1695 continue; /* we need only unicast addresses */ 1696 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 1697 (icmp6_nodeinfo & ICMP6_NODEINFO_TMPADDROK) == 0) { 1698 continue; 1699 } 1700 addrsofif++; /* count the address */ 1701 } 1702 if (iffound) { 1703 *ifpp = ifp; 1704 IFNET_RUNLOCK(); 1705 return (addrsofif); 1706 } 1707 1708 addrs += addrsofif; 1709 } 1710 IFNET_RUNLOCK(); 1711 1712 return (addrs); 1713 } 1714 1715 static int 1716 ni6_store_addrs(struct icmp6_nodeinfo *ni6, struct icmp6_nodeinfo *nni6, 1717 struct ifnet *ifp0, int resid) 1718 { 1719 struct ifnet *ifp = ifp0 ? ifp0 : TAILQ_FIRST(&ifnet); 1720 struct in6_ifaddr *ifa6; 1721 struct ifaddr *ifa; 1722 struct ifnet *ifp_dep = NULL; 1723 int copied = 0, allow_deprecated = 0; 1724 u_char *cp = (u_char *)(nni6 + 1); 1725 int niflags = ni6->ni_flags; 1726 u_int32_t ltime; 1727 1728 if (ifp0 == NULL && !(niflags & NI_NODEADDR_FLAG_ALL)) 1729 return (0); /* needless to copy */ 1730 1731 IFNET_RLOCK(); 1732 again: 1733 1734 for (; ifp; ifp = TAILQ_NEXT(ifp, if_list)) { 1735 for (ifa = ifp->if_addrlist.tqh_first; ifa; 1736 ifa = ifa->ifa_list.tqe_next) { 1737 if (ifa->ifa_addr->sa_family != AF_INET6) 1738 continue; 1739 ifa6 = (struct in6_ifaddr *)ifa; 1740 1741 if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) != 0 && 1742 allow_deprecated == 0) { 1743 /* 1744 * prefererred address should be put before 1745 * deprecated addresses. 1746 */ 1747 1748 /* record the interface for later search */ 1749 if (ifp_dep == NULL) 1750 ifp_dep = ifp; 1751 1752 continue; 1753 } else if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) == 0 && 1754 allow_deprecated != 0) 1755 continue; /* we now collect deprecated addrs */ 1756 1757 /* What do we have to do about ::1? */ 1758 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1759 case IPV6_ADDR_SCOPE_LINKLOCAL: 1760 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0) 1761 continue; 1762 break; 1763 case IPV6_ADDR_SCOPE_SITELOCAL: 1764 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0) 1765 continue; 1766 break; 1767 case IPV6_ADDR_SCOPE_GLOBAL: 1768 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0) 1769 continue; 1770 break; 1771 default: 1772 continue; 1773 } 1774 1775 /* 1776 * check if anycast is okay. 1777 * XXX: just experimental. not in the spec. 1778 */ 1779 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 && 1780 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0) 1781 continue; 1782 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 1783 (icmp6_nodeinfo & ICMP6_NODEINFO_TMPADDROK) == 0) { 1784 continue; 1785 } 1786 1787 /* now we can copy the address */ 1788 if (resid < sizeof(struct in6_addr) + 1789 sizeof(u_int32_t)) { 1790 /* 1791 * We give up much more copy. 1792 * Set the truncate flag and return. 1793 */ 1794 nni6->ni_flags |= NI_NODEADDR_FLAG_TRUNCATE; 1795 IFNET_RUNLOCK(); 1796 return (copied); 1797 } 1798 1799 /* 1800 * Set the TTL of the address. 1801 * The TTL value should be one of the following 1802 * according to the specification: 1803 * 1804 * 1. The remaining lifetime of a DHCP lease on the 1805 * address, or 1806 * 2. The remaining Valid Lifetime of a prefix from 1807 * which the address was derived through Stateless 1808 * Autoconfiguration. 1809 * 1810 * Note that we currently do not support stateful 1811 * address configuration by DHCPv6, so the former 1812 * case can't happen. 1813 */ 1814 if (ifa6->ia6_lifetime.ia6t_expire == 0) 1815 ltime = ND6_INFINITE_LIFETIME; 1816 else { 1817 if (ifa6->ia6_lifetime.ia6t_expire > 1818 time_second) 1819 ltime = htonl(ifa6->ia6_lifetime.ia6t_expire - time_second); 1820 else 1821 ltime = 0; 1822 } 1823 1824 bcopy(<ime, cp, sizeof(u_int32_t)); 1825 cp += sizeof(u_int32_t); 1826 1827 /* copy the address itself */ 1828 bcopy(&ifa6->ia_addr.sin6_addr, cp, 1829 sizeof(struct in6_addr)); 1830 in6_clearscope((struct in6_addr *)cp); /* XXX */ 1831 cp += sizeof(struct in6_addr); 1832 1833 resid -= (sizeof(struct in6_addr) + sizeof(u_int32_t)); 1834 copied += (sizeof(struct in6_addr) + sizeof(u_int32_t)); 1835 } 1836 if (ifp0) /* we need search only on the specified IF */ 1837 break; 1838 } 1839 1840 if (allow_deprecated == 0 && ifp_dep != NULL) { 1841 ifp = ifp_dep; 1842 allow_deprecated = 1; 1843 1844 goto again; 1845 } 1846 1847 IFNET_RUNLOCK(); 1848 1849 return (copied); 1850 } 1851 1852 /* 1853 * XXX almost dup'ed code with rip6_input. 1854 */ 1855 static int 1856 icmp6_rip6_input(struct mbuf **mp, 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 SOCKBUF_LOCK(&last->in6p_socket->so_rcv); 1951 if (sbappendaddr_locked( 1952 &last->in6p_socket->so_rcv, 1953 (struct sockaddr *)&fromsa, n, opts) 1954 == 0) { 1955 /* should notify about lost packet */ 1956 m_freem(n); 1957 if (opts) { 1958 m_freem(opts); 1959 } 1960 SOCKBUF_UNLOCK( 1961 &last->in6p_socket->so_rcv); 1962 } else 1963 sorwakeup_locked(last->in6p_socket); 1964 opts = NULL; 1965 } 1966 INP_UNLOCK(last); 1967 } 1968 last = in6p; 1969 } 1970 if (last) { 1971 if (last->in6p_flags & IN6P_CONTROLOPTS) 1972 ip6_savecontrol(last, m, &opts); 1973 /* strip intermediate headers */ 1974 m_adj(m, off); 1975 1976 /* avoid using mbuf clusters if possible (see above) */ 1977 if ((m->m_flags & M_EXT) && m->m_next == NULL && 1978 m->m_len <= MHLEN) { 1979 struct mbuf *n; 1980 1981 MGET(n, M_DONTWAIT, m->m_type); 1982 if (n != NULL) { 1983 if (m_dup_pkthdr(n, m, M_NOWAIT)) { 1984 bcopy(m->m_data, n->m_data, m->m_len); 1985 n->m_len = m->m_len; 1986 1987 m_freem(m); 1988 m = n; 1989 } else { 1990 m_freem(n); 1991 n = NULL; 1992 } 1993 } 1994 } 1995 SOCKBUF_LOCK(&last->in6p_socket->so_rcv); 1996 if (sbappendaddr_locked(&last->in6p_socket->so_rcv, 1997 (struct sockaddr *)&fromsa, m, opts) == 0) { 1998 m_freem(m); 1999 if (opts) 2000 m_freem(opts); 2001 SOCKBUF_UNLOCK(&last->in6p_socket->so_rcv); 2002 } else 2003 sorwakeup_locked(last->in6p_socket); 2004 INP_UNLOCK(last); 2005 } else { 2006 m_freem(m); 2007 ip6stat.ip6s_delivered--; 2008 } 2009 INP_INFO_RUNLOCK(&ripcbinfo); 2010 return IPPROTO_DONE; 2011 } 2012 2013 /* 2014 * Reflect the ip6 packet back to the source. 2015 * OFF points to the icmp6 header, counted from the top of the mbuf. 2016 */ 2017 void 2018 icmp6_reflect(struct mbuf *m, size_t off) 2019 { 2020 struct ip6_hdr *ip6; 2021 struct icmp6_hdr *icmp6; 2022 struct in6_ifaddr *ia; 2023 int plen; 2024 int type, code; 2025 struct ifnet *outif = NULL; 2026 struct in6_addr origdst, *src = NULL; 2027 2028 /* too short to reflect */ 2029 if (off < sizeof(struct ip6_hdr)) { 2030 nd6log((LOG_DEBUG, 2031 "sanity fail: off=%lx, sizeof(ip6)=%lx in %s:%d\n", 2032 (u_long)off, (u_long)sizeof(struct ip6_hdr), 2033 __FILE__, __LINE__)); 2034 goto bad; 2035 } 2036 2037 /* 2038 * If there are extra headers between IPv6 and ICMPv6, strip 2039 * off that header first. 2040 */ 2041 #ifdef DIAGNOSTIC 2042 if (sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) > MHLEN) 2043 panic("assumption failed in icmp6_reflect"); 2044 #endif 2045 if (off > sizeof(struct ip6_hdr)) { 2046 size_t l; 2047 struct ip6_hdr nip6; 2048 2049 l = off - sizeof(struct ip6_hdr); 2050 m_copydata(m, 0, sizeof(nip6), (caddr_t)&nip6); 2051 m_adj(m, l); 2052 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 2053 if (m->m_len < l) { 2054 if ((m = m_pullup(m, l)) == NULL) 2055 return; 2056 } 2057 bcopy((caddr_t)&nip6, mtod(m, caddr_t), sizeof(nip6)); 2058 } else /* off == sizeof(struct ip6_hdr) */ { 2059 size_t l; 2060 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 2061 if (m->m_len < l) { 2062 if ((m = m_pullup(m, l)) == NULL) 2063 return; 2064 } 2065 } 2066 plen = m->m_pkthdr.len - sizeof(struct ip6_hdr); 2067 ip6 = mtod(m, struct ip6_hdr *); 2068 ip6->ip6_nxt = IPPROTO_ICMPV6; 2069 icmp6 = (struct icmp6_hdr *)(ip6 + 1); 2070 type = icmp6->icmp6_type; /* keep type for statistics */ 2071 code = icmp6->icmp6_code; /* ditto. */ 2072 2073 origdst = ip6->ip6_dst; 2074 /* 2075 * ip6_input() drops a packet if its src is multicast. 2076 * So, the src is never multicast. 2077 */ 2078 ip6->ip6_dst = ip6->ip6_src; 2079 2080 /* 2081 * If the incoming packet was addressed directly to us (i.e. unicast), 2082 * use dst as the src for the reply. 2083 * The IN6_IFF_NOTREADY case should be VERY rare, but is possible 2084 * (for example) when we encounter an error while forwarding procedure 2085 * destined to a duplicated address of ours. 2086 * Note that ip6_getdstifaddr() may fail if we are in an error handling 2087 * procedure of an outgoing packet of our own, in which case we need 2088 * to search in the ifaddr list. 2089 */ 2090 if (!IN6_IS_ADDR_MULTICAST(&origdst)) { 2091 if ((ia = ip6_getdstifaddr(m))) { 2092 if (!(ia->ia6_flags & 2093 (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY))) 2094 src = &ia->ia_addr.sin6_addr; 2095 } else { 2096 struct sockaddr_in6 d; 2097 2098 bzero(&d, sizeof(d)); 2099 d.sin6_family = AF_INET6; 2100 d.sin6_len = sizeof(d); 2101 d.sin6_addr = origdst; 2102 ia = (struct in6_ifaddr *) 2103 ifa_ifwithaddr((struct sockaddr *)&d); 2104 if (ia && 2105 !(ia->ia6_flags & 2106 (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY))) { 2107 src = &ia->ia_addr.sin6_addr; 2108 } 2109 } 2110 } 2111 2112 if (src == NULL) { 2113 int e; 2114 struct sockaddr_in6 sin6; 2115 struct route_in6 ro; 2116 2117 /* 2118 * This case matches to multicasts, our anycast, or unicasts 2119 * that we do not own. Select a source address based on the 2120 * source address of the erroneous packet. 2121 */ 2122 bzero(&sin6, sizeof(sin6)); 2123 sin6.sin6_family = AF_INET6; 2124 sin6.sin6_len = sizeof(sin6); 2125 sin6.sin6_addr = ip6->ip6_dst; /* zone ID should be embedded */ 2126 2127 bzero(&ro, sizeof(ro)); 2128 src = in6_selectsrc(&sin6, NULL, NULL, &ro, NULL, &outif, &e); 2129 if (ro.ro_rt) 2130 RTFREE(ro.ro_rt); /* XXX: we could use this */ 2131 if (src == NULL) { 2132 char ip6buf[INET6_ADDRSTRLEN]; 2133 nd6log((LOG_DEBUG, 2134 "icmp6_reflect: source can't be determined: " 2135 "dst=%s, error=%d\n", 2136 ip6_sprintf(ip6buf, &sin6.sin6_addr), e)); 2137 goto bad; 2138 } 2139 } 2140 2141 ip6->ip6_src = *src; 2142 ip6->ip6_flow = 0; 2143 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2144 ip6->ip6_vfc |= IPV6_VERSION; 2145 ip6->ip6_nxt = IPPROTO_ICMPV6; 2146 if (outif) 2147 ip6->ip6_hlim = ND_IFINFO(outif)->chlim; 2148 else if (m->m_pkthdr.rcvif) { 2149 /* XXX: This may not be the outgoing interface */ 2150 ip6->ip6_hlim = ND_IFINFO(m->m_pkthdr.rcvif)->chlim; 2151 } else 2152 ip6->ip6_hlim = ip6_defhlim; 2153 2154 icmp6->icmp6_cksum = 0; 2155 icmp6->icmp6_cksum = in6_cksum(m, IPPROTO_ICMPV6, 2156 sizeof(struct ip6_hdr), plen); 2157 2158 /* 2159 * XXX option handling 2160 */ 2161 2162 m->m_flags &= ~(M_BCAST|M_MCAST); 2163 2164 ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL); 2165 if (outif) 2166 icmp6_ifoutstat_inc(outif, type, code); 2167 2168 return; 2169 2170 bad: 2171 m_freem(m); 2172 return; 2173 } 2174 2175 void 2176 icmp6_fasttimo(void) 2177 { 2178 2179 return; 2180 } 2181 2182 static const char * 2183 icmp6_redirect_diag(struct in6_addr *src6, struct in6_addr *dst6, 2184 struct in6_addr *tgt6) 2185 { 2186 static char buf[1024]; 2187 char ip6bufs[INET6_ADDRSTRLEN]; 2188 char ip6bufd[INET6_ADDRSTRLEN]; 2189 char ip6buft[INET6_ADDRSTRLEN]; 2190 snprintf(buf, sizeof(buf), "(src=%s dst=%s tgt=%s)", 2191 ip6_sprintf(ip6bufs, src6), ip6_sprintf(ip6bufd, dst6), 2192 ip6_sprintf(ip6buft, tgt6)); 2193 return buf; 2194 } 2195 2196 void 2197 icmp6_redirect_input(struct mbuf *m, int off) 2198 { 2199 struct ifnet *ifp; 2200 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 2201 struct nd_redirect *nd_rd; 2202 int icmp6len = ntohs(ip6->ip6_plen); 2203 char *lladdr = NULL; 2204 int lladdrlen = 0; 2205 u_char *redirhdr = NULL; 2206 int redirhdrlen = 0; 2207 struct rtentry *rt = NULL; 2208 int is_router; 2209 int is_onlink; 2210 struct in6_addr src6 = ip6->ip6_src; 2211 struct in6_addr redtgt6; 2212 struct in6_addr reddst6; 2213 union nd_opts ndopts; 2214 char ip6buf[INET6_ADDRSTRLEN]; 2215 2216 if (!m) 2217 return; 2218 2219 ifp = m->m_pkthdr.rcvif; 2220 2221 if (!ifp) 2222 return; 2223 2224 /* XXX if we are router, we don't update route by icmp6 redirect */ 2225 if (ip6_forwarding) 2226 goto freeit; 2227 if (!icmp6_rediraccept) 2228 goto freeit; 2229 2230 #ifndef PULLDOWN_TEST 2231 IP6_EXTHDR_CHECK(m, off, icmp6len,); 2232 nd_rd = (struct nd_redirect *)((caddr_t)ip6 + off); 2233 #else 2234 IP6_EXTHDR_GET(nd_rd, struct nd_redirect *, m, off, icmp6len); 2235 if (nd_rd == NULL) { 2236 icmp6stat.icp6s_tooshort++; 2237 return; 2238 } 2239 #endif 2240 redtgt6 = nd_rd->nd_rd_target; 2241 reddst6 = nd_rd->nd_rd_dst; 2242 2243 if (in6_setscope(&redtgt6, m->m_pkthdr.rcvif, NULL) || 2244 in6_setscope(&reddst6, m->m_pkthdr.rcvif, NULL)) { 2245 goto freeit; 2246 } 2247 2248 /* validation */ 2249 if (!IN6_IS_ADDR_LINKLOCAL(&src6)) { 2250 nd6log((LOG_ERR, 2251 "ICMP6 redirect sent from %s rejected; " 2252 "must be from linklocal\n", 2253 ip6_sprintf(ip6buf, &src6))); 2254 goto bad; 2255 } 2256 if (ip6->ip6_hlim != 255) { 2257 nd6log((LOG_ERR, 2258 "ICMP6 redirect sent from %s rejected; " 2259 "hlim=%d (must be 255)\n", 2260 ip6_sprintf(ip6buf, &src6), ip6->ip6_hlim)); 2261 goto bad; 2262 } 2263 { 2264 /* ip6->ip6_src must be equal to gw for icmp6->icmp6_reddst */ 2265 struct sockaddr_in6 sin6; 2266 struct in6_addr *gw6; 2267 2268 bzero(&sin6, sizeof(sin6)); 2269 sin6.sin6_family = AF_INET6; 2270 sin6.sin6_len = sizeof(struct sockaddr_in6); 2271 bcopy(&reddst6, &sin6.sin6_addr, sizeof(reddst6)); 2272 rt = rtalloc1((struct sockaddr *)&sin6, 0, 0UL); 2273 if (rt) { 2274 if (rt->rt_gateway == NULL || 2275 rt->rt_gateway->sa_family != AF_INET6) { 2276 nd6log((LOG_ERR, 2277 "ICMP6 redirect rejected; no route " 2278 "with inet6 gateway found for redirect dst: %s\n", 2279 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2280 RTFREE_LOCKED(rt); 2281 goto bad; 2282 } 2283 2284 gw6 = &(((struct sockaddr_in6 *)rt->rt_gateway)->sin6_addr); 2285 if (bcmp(&src6, gw6, sizeof(struct in6_addr)) != 0) { 2286 nd6log((LOG_ERR, 2287 "ICMP6 redirect rejected; " 2288 "not equal to gw-for-src=%s (must be same): " 2289 "%s\n", 2290 ip6_sprintf(ip6buf, gw6), 2291 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2292 RTFREE_LOCKED(rt); 2293 goto bad; 2294 } 2295 } else { 2296 nd6log((LOG_ERR, 2297 "ICMP6 redirect rejected; " 2298 "no route found for redirect dst: %s\n", 2299 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2300 goto bad; 2301 } 2302 RTFREE_LOCKED(rt); 2303 rt = NULL; 2304 } 2305 if (IN6_IS_ADDR_MULTICAST(&reddst6)) { 2306 nd6log((LOG_ERR, 2307 "ICMP6 redirect rejected; " 2308 "redirect dst must be unicast: %s\n", 2309 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2310 goto bad; 2311 } 2312 2313 is_router = is_onlink = 0; 2314 if (IN6_IS_ADDR_LINKLOCAL(&redtgt6)) 2315 is_router = 1; /* router case */ 2316 if (bcmp(&redtgt6, &reddst6, sizeof(redtgt6)) == 0) 2317 is_onlink = 1; /* on-link destination case */ 2318 if (!is_router && !is_onlink) { 2319 nd6log((LOG_ERR, 2320 "ICMP6 redirect rejected; " 2321 "neither router case nor onlink case: %s\n", 2322 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2323 goto bad; 2324 } 2325 /* validation passed */ 2326 2327 icmp6len -= sizeof(*nd_rd); 2328 nd6_option_init(nd_rd + 1, icmp6len, &ndopts); 2329 if (nd6_options(&ndopts) < 0) { 2330 nd6log((LOG_INFO, "icmp6_redirect_input: " 2331 "invalid ND option, rejected: %s\n", 2332 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2333 /* nd6_options have incremented stats */ 2334 goto freeit; 2335 } 2336 2337 if (ndopts.nd_opts_tgt_lladdr) { 2338 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 2339 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 2340 } 2341 2342 if (ndopts.nd_opts_rh) { 2343 redirhdrlen = ndopts.nd_opts_rh->nd_opt_rh_len; 2344 redirhdr = (u_char *)(ndopts.nd_opts_rh + 1); /* xxx */ 2345 } 2346 2347 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 2348 nd6log((LOG_INFO, 2349 "icmp6_redirect_input: lladdrlen mismatch for %s " 2350 "(if %d, icmp6 packet %d): %s\n", 2351 ip6_sprintf(ip6buf, &redtgt6), 2352 ifp->if_addrlen, lladdrlen - 2, 2353 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2354 goto bad; 2355 } 2356 2357 /* RFC 2461 8.3 */ 2358 nd6_cache_lladdr(ifp, &redtgt6, lladdr, lladdrlen, ND_REDIRECT, 2359 is_onlink ? ND_REDIRECT_ONLINK : ND_REDIRECT_ROUTER); 2360 2361 if (!is_onlink) { /* better router case. perform rtredirect. */ 2362 /* perform rtredirect */ 2363 struct sockaddr_in6 sdst; 2364 struct sockaddr_in6 sgw; 2365 struct sockaddr_in6 ssrc; 2366 2367 bzero(&sdst, sizeof(sdst)); 2368 bzero(&sgw, sizeof(sgw)); 2369 bzero(&ssrc, sizeof(ssrc)); 2370 sdst.sin6_family = sgw.sin6_family = ssrc.sin6_family = AF_INET6; 2371 sdst.sin6_len = sgw.sin6_len = ssrc.sin6_len = 2372 sizeof(struct sockaddr_in6); 2373 bcopy(&redtgt6, &sgw.sin6_addr, sizeof(struct in6_addr)); 2374 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2375 bcopy(&src6, &ssrc.sin6_addr, sizeof(struct in6_addr)); 2376 rtredirect((struct sockaddr *)&sdst, (struct sockaddr *)&sgw, 2377 (struct sockaddr *)NULL, RTF_GATEWAY | RTF_HOST, 2378 (struct sockaddr *)&ssrc); 2379 } 2380 /* finally update cached route in each socket via pfctlinput */ 2381 { 2382 struct sockaddr_in6 sdst; 2383 2384 bzero(&sdst, sizeof(sdst)); 2385 sdst.sin6_family = AF_INET6; 2386 sdst.sin6_len = sizeof(struct sockaddr_in6); 2387 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2388 pfctlinput(PRC_REDIRECT_HOST, (struct sockaddr *)&sdst); 2389 #ifdef IPSEC 2390 key_sa_routechange((struct sockaddr *)&sdst); 2391 #endif /* IPSEC */ 2392 } 2393 2394 freeit: 2395 m_freem(m); 2396 return; 2397 2398 bad: 2399 icmp6stat.icp6s_badredirect++; 2400 m_freem(m); 2401 } 2402 2403 void 2404 icmp6_redirect_output(struct mbuf *m0, struct rtentry *rt) 2405 { 2406 struct ifnet *ifp; /* my outgoing interface */ 2407 struct in6_addr *ifp_ll6; 2408 struct in6_addr *router_ll6; 2409 struct ip6_hdr *sip6; /* m0 as struct ip6_hdr */ 2410 struct mbuf *m = NULL; /* newly allocated one */ 2411 struct ip6_hdr *ip6; /* m as struct ip6_hdr */ 2412 struct nd_redirect *nd_rd; 2413 size_t maxlen; 2414 u_char *p; 2415 struct ifnet *outif = NULL; 2416 struct sockaddr_in6 src_sa; 2417 2418 icmp6_errcount(&icmp6stat.icp6s_outerrhist, ND_REDIRECT, 0); 2419 2420 /* if we are not router, we don't send icmp6 redirect */ 2421 if (!ip6_forwarding) 2422 goto fail; 2423 2424 /* sanity check */ 2425 if (!m0 || !rt || !(rt->rt_flags & RTF_UP) || !(ifp = rt->rt_ifp)) 2426 goto fail; 2427 2428 /* 2429 * Address check: 2430 * the source address must identify a neighbor, and 2431 * the destination address must not be a multicast address 2432 * [RFC 2461, sec 8.2] 2433 */ 2434 sip6 = mtod(m0, struct ip6_hdr *); 2435 bzero(&src_sa, sizeof(src_sa)); 2436 src_sa.sin6_family = AF_INET6; 2437 src_sa.sin6_len = sizeof(src_sa); 2438 src_sa.sin6_addr = sip6->ip6_src; 2439 if (nd6_is_addr_neighbor(&src_sa, ifp) == 0) 2440 goto fail; 2441 if (IN6_IS_ADDR_MULTICAST(&sip6->ip6_dst)) 2442 goto fail; /* what should we do here? */ 2443 2444 /* rate limit */ 2445 if (icmp6_ratelimit(&sip6->ip6_src, ND_REDIRECT, 0)) 2446 goto fail; 2447 2448 /* 2449 * Since we are going to append up to 1280 bytes (= IPV6_MMTU), 2450 * we almost always ask for an mbuf cluster for simplicity. 2451 * (MHLEN < IPV6_MMTU is almost always true) 2452 */ 2453 #if IPV6_MMTU >= MCLBYTES 2454 # error assumption failed about IPV6_MMTU and MCLBYTES 2455 #endif 2456 MGETHDR(m, M_DONTWAIT, MT_HEADER); 2457 if (m && IPV6_MMTU >= MHLEN) 2458 MCLGET(m, M_DONTWAIT); 2459 if (!m) 2460 goto fail; 2461 m->m_pkthdr.rcvif = NULL; 2462 m->m_len = 0; 2463 maxlen = M_TRAILINGSPACE(m); 2464 maxlen = min(IPV6_MMTU, maxlen); 2465 /* just for safety */ 2466 if (maxlen < sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) + 2467 ((sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7)) { 2468 goto fail; 2469 } 2470 2471 { 2472 /* get ip6 linklocal address for ifp(my outgoing interface). */ 2473 struct in6_ifaddr *ia; 2474 if ((ia = in6ifa_ifpforlinklocal(ifp, 2475 IN6_IFF_NOTREADY| 2476 IN6_IFF_ANYCAST)) == NULL) 2477 goto fail; 2478 ifp_ll6 = &ia->ia_addr.sin6_addr; 2479 } 2480 2481 /* get ip6 linklocal address for the router. */ 2482 if (rt->rt_gateway && (rt->rt_flags & RTF_GATEWAY)) { 2483 struct sockaddr_in6 *sin6; 2484 sin6 = (struct sockaddr_in6 *)rt->rt_gateway; 2485 router_ll6 = &sin6->sin6_addr; 2486 if (!IN6_IS_ADDR_LINKLOCAL(router_ll6)) 2487 router_ll6 = (struct in6_addr *)NULL; 2488 } else 2489 router_ll6 = (struct in6_addr *)NULL; 2490 2491 /* ip6 */ 2492 ip6 = mtod(m, struct ip6_hdr *); 2493 ip6->ip6_flow = 0; 2494 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2495 ip6->ip6_vfc |= IPV6_VERSION; 2496 /* ip6->ip6_plen will be set later */ 2497 ip6->ip6_nxt = IPPROTO_ICMPV6; 2498 ip6->ip6_hlim = 255; 2499 /* ip6->ip6_src must be linklocal addr for my outgoing if. */ 2500 bcopy(ifp_ll6, &ip6->ip6_src, sizeof(struct in6_addr)); 2501 bcopy(&sip6->ip6_src, &ip6->ip6_dst, sizeof(struct in6_addr)); 2502 2503 /* ND Redirect */ 2504 nd_rd = (struct nd_redirect *)(ip6 + 1); 2505 nd_rd->nd_rd_type = ND_REDIRECT; 2506 nd_rd->nd_rd_code = 0; 2507 nd_rd->nd_rd_reserved = 0; 2508 if (rt->rt_flags & RTF_GATEWAY) { 2509 /* 2510 * nd_rd->nd_rd_target must be a link-local address in 2511 * better router cases. 2512 */ 2513 if (!router_ll6) 2514 goto fail; 2515 bcopy(router_ll6, &nd_rd->nd_rd_target, 2516 sizeof(nd_rd->nd_rd_target)); 2517 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2518 sizeof(nd_rd->nd_rd_dst)); 2519 } else { 2520 /* make sure redtgt == reddst */ 2521 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_target, 2522 sizeof(nd_rd->nd_rd_target)); 2523 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2524 sizeof(nd_rd->nd_rd_dst)); 2525 } 2526 2527 p = (u_char *)(nd_rd + 1); 2528 2529 if (!router_ll6) 2530 goto nolladdropt; 2531 2532 { 2533 /* target lladdr option */ 2534 struct rtentry *rt_router = NULL; 2535 int len; 2536 struct sockaddr_dl *sdl; 2537 struct nd_opt_hdr *nd_opt; 2538 char *lladdr; 2539 2540 rt_router = nd6_lookup(router_ll6, 0, ifp); 2541 if (!rt_router) 2542 goto nolladdropt; 2543 len = sizeof(*nd_opt) + ifp->if_addrlen; 2544 len = (len + 7) & ~7; /* round by 8 */ 2545 /* safety check */ 2546 if (len + (p - (u_char *)ip6) > maxlen) 2547 goto nolladdropt; 2548 if (!(rt_router->rt_flags & RTF_GATEWAY) && 2549 (rt_router->rt_flags & RTF_LLINFO) && 2550 (rt_router->rt_gateway->sa_family == AF_LINK) && 2551 (sdl = (struct sockaddr_dl *)rt_router->rt_gateway) && 2552 sdl->sdl_alen) { 2553 nd_opt = (struct nd_opt_hdr *)p; 2554 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 2555 nd_opt->nd_opt_len = len >> 3; 2556 lladdr = (char *)(nd_opt + 1); 2557 bcopy(LLADDR(sdl), lladdr, ifp->if_addrlen); 2558 p += len; 2559 } 2560 } 2561 nolladdropt:; 2562 2563 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2564 2565 /* just to be safe */ 2566 #ifdef M_DECRYPTED /*not openbsd*/ 2567 if (m0->m_flags & M_DECRYPTED) 2568 goto noredhdropt; 2569 #endif 2570 if (p - (u_char *)ip6 > maxlen) 2571 goto noredhdropt; 2572 2573 { 2574 /* redirected header option */ 2575 int len; 2576 struct nd_opt_rd_hdr *nd_opt_rh; 2577 2578 /* 2579 * compute the maximum size for icmp6 redirect header option. 2580 * XXX room for auth header? 2581 */ 2582 len = maxlen - (p - (u_char *)ip6); 2583 len &= ~7; 2584 2585 /* This is just for simplicity. */ 2586 if (m0->m_pkthdr.len != m0->m_len) { 2587 if (m0->m_next) { 2588 m_freem(m0->m_next); 2589 m0->m_next = NULL; 2590 } 2591 m0->m_pkthdr.len = m0->m_len; 2592 } 2593 2594 /* 2595 * Redirected header option spec (RFC2461 4.6.3) talks nothing 2596 * about padding/truncate rule for the original IP packet. 2597 * From the discussion on IPv6imp in Feb 1999, 2598 * the consensus was: 2599 * - "attach as much as possible" is the goal 2600 * - pad if not aligned (original size can be guessed by 2601 * original ip6 header) 2602 * Following code adds the padding if it is simple enough, 2603 * and truncates if not. 2604 */ 2605 if (m0->m_next || m0->m_pkthdr.len != m0->m_len) 2606 panic("assumption failed in %s:%d", __FILE__, 2607 __LINE__); 2608 2609 if (len - sizeof(*nd_opt_rh) < m0->m_pkthdr.len) { 2610 /* not enough room, truncate */ 2611 m0->m_pkthdr.len = m0->m_len = len - 2612 sizeof(*nd_opt_rh); 2613 } else { 2614 /* enough room, pad or truncate */ 2615 size_t extra; 2616 2617 extra = m0->m_pkthdr.len % 8; 2618 if (extra) { 2619 /* pad if easy enough, truncate if not */ 2620 if (8 - extra <= M_TRAILINGSPACE(m0)) { 2621 /* pad */ 2622 m0->m_len += (8 - extra); 2623 m0->m_pkthdr.len += (8 - extra); 2624 } else { 2625 /* truncate */ 2626 m0->m_pkthdr.len -= extra; 2627 m0->m_len -= extra; 2628 } 2629 } 2630 len = m0->m_pkthdr.len + sizeof(*nd_opt_rh); 2631 m0->m_pkthdr.len = m0->m_len = len - 2632 sizeof(*nd_opt_rh); 2633 } 2634 2635 nd_opt_rh = (struct nd_opt_rd_hdr *)p; 2636 bzero(nd_opt_rh, sizeof(*nd_opt_rh)); 2637 nd_opt_rh->nd_opt_rh_type = ND_OPT_REDIRECTED_HEADER; 2638 nd_opt_rh->nd_opt_rh_len = len >> 3; 2639 p += sizeof(*nd_opt_rh); 2640 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2641 2642 /* connect m0 to m */ 2643 m_tag_delete_chain(m0, NULL); 2644 m0->m_flags &= ~M_PKTHDR; 2645 m->m_next = m0; 2646 m->m_pkthdr.len = m->m_len + m0->m_len; 2647 m0 = NULL; 2648 } 2649 noredhdropt:; 2650 if (m0) { 2651 m_freem(m0); 2652 m0 = NULL; 2653 } 2654 2655 /* XXX: clear embedded link IDs in the inner header */ 2656 in6_clearscope(&sip6->ip6_src); 2657 in6_clearscope(&sip6->ip6_dst); 2658 in6_clearscope(&nd_rd->nd_rd_target); 2659 in6_clearscope(&nd_rd->nd_rd_dst); 2660 2661 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr)); 2662 2663 nd_rd->nd_rd_cksum = 0; 2664 nd_rd->nd_rd_cksum = in6_cksum(m, IPPROTO_ICMPV6, 2665 sizeof(*ip6), ntohs(ip6->ip6_plen)); 2666 2667 /* send the packet to outside... */ 2668 ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL); 2669 if (outif) { 2670 icmp6_ifstat_inc(outif, ifs6_out_msg); 2671 icmp6_ifstat_inc(outif, ifs6_out_redirect); 2672 } 2673 icmp6stat.icp6s_outhist[ND_REDIRECT]++; 2674 2675 return; 2676 2677 fail: 2678 if (m) 2679 m_freem(m); 2680 if (m0) 2681 m_freem(m0); 2682 } 2683 2684 /* 2685 * ICMPv6 socket option processing. 2686 */ 2687 int 2688 icmp6_ctloutput(struct socket *so, struct sockopt *sopt) 2689 { 2690 int error = 0; 2691 int optlen; 2692 struct inpcb *inp = sotoinpcb(so); 2693 int level, op, optname; 2694 2695 if (sopt) { 2696 level = sopt->sopt_level; 2697 op = sopt->sopt_dir; 2698 optname = sopt->sopt_name; 2699 optlen = sopt->sopt_valsize; 2700 } else 2701 level = op = optname = optlen = 0; 2702 2703 if (level != IPPROTO_ICMPV6) { 2704 return EINVAL; 2705 } 2706 2707 switch (op) { 2708 case PRCO_SETOPT: 2709 switch (optname) { 2710 case ICMP6_FILTER: 2711 { 2712 struct icmp6_filter *p; 2713 2714 if (optlen != sizeof(*p)) { 2715 error = EMSGSIZE; 2716 break; 2717 } 2718 if (inp->in6p_icmp6filt == NULL) { 2719 error = EINVAL; 2720 break; 2721 } 2722 error = sooptcopyin(sopt, inp->in6p_icmp6filt, optlen, 2723 optlen); 2724 break; 2725 } 2726 2727 default: 2728 error = ENOPROTOOPT; 2729 break; 2730 } 2731 break; 2732 2733 case PRCO_GETOPT: 2734 switch (optname) { 2735 case ICMP6_FILTER: 2736 { 2737 if (inp->in6p_icmp6filt == NULL) { 2738 error = EINVAL; 2739 break; 2740 } 2741 error = sooptcopyout(sopt, inp->in6p_icmp6filt, 2742 sizeof(struct icmp6_filter)); 2743 break; 2744 } 2745 2746 default: 2747 error = ENOPROTOOPT; 2748 break; 2749 } 2750 break; 2751 } 2752 2753 return (error); 2754 } 2755 2756 /* 2757 * Perform rate limit check. 2758 * Returns 0 if it is okay to send the icmp6 packet. 2759 * Returns 1 if the router SHOULD NOT send this icmp6 packet due to rate 2760 * limitation. 2761 * 2762 * XXX per-destination/type check necessary? 2763 * 2764 * dst - not used at this moment 2765 * type - not used at this moment 2766 * code - not used at this moment 2767 */ 2768 static int 2769 icmp6_ratelimit(const struct in6_addr *dst, const int type, 2770 const int code) 2771 { 2772 int ret; 2773 2774 ret = 0; /* okay to send */ 2775 2776 /* PPS limit */ 2777 if (!ppsratecheck(&icmp6errppslim_last, &icmp6errpps_count, 2778 icmp6errppslim)) { 2779 /* The packet is subject to rate limit */ 2780 ret++; 2781 } 2782 2783 return ret; 2784 } 2785