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 extern struct domain inet6domain; 113 114 struct icmp6stat icmp6stat; 115 116 extern struct inpcbinfo ripcbinfo; 117 extern struct inpcbhead ripcb; 118 extern int icmp6errppslim; 119 static int icmp6errpps_count = 0; 120 static struct timeval icmp6errppslim_last; 121 extern int icmp6_nodeinfo; 122 123 static void icmp6_errcount __P((struct icmp6errstat *, int, int)); 124 static int icmp6_rip6_input __P((struct mbuf **, int)); 125 static int icmp6_ratelimit __P((const struct in6_addr *, const int, const int)); 126 static const char *icmp6_redirect_diag __P((struct in6_addr *, 127 struct in6_addr *, struct in6_addr *)); 128 static struct mbuf *ni6_input __P((struct mbuf *, int)); 129 static struct mbuf *ni6_nametodns __P((const char *, int, int)); 130 static int ni6_dnsmatch __P((const char *, int, const char *, int)); 131 static int ni6_addrs __P((struct icmp6_nodeinfo *, struct mbuf *, 132 struct ifnet **, struct in6_addr *)); 133 static int ni6_store_addrs __P((struct icmp6_nodeinfo *, struct icmp6_nodeinfo *, 134 struct ifnet *, int)); 135 static int icmp6_notify_error __P((struct mbuf **, int, int, int)); 136 137 138 void 139 icmp6_init() 140 { 141 mld6_init(); 142 } 143 144 static void 145 icmp6_errcount(stat, type, code) 146 struct icmp6errstat *stat; 147 int type, code; 148 { 149 switch (type) { 150 case ICMP6_DST_UNREACH: 151 switch (code) { 152 case ICMP6_DST_UNREACH_NOROUTE: 153 stat->icp6errs_dst_unreach_noroute++; 154 return; 155 case ICMP6_DST_UNREACH_ADMIN: 156 stat->icp6errs_dst_unreach_admin++; 157 return; 158 case ICMP6_DST_UNREACH_BEYONDSCOPE: 159 stat->icp6errs_dst_unreach_beyondscope++; 160 return; 161 case ICMP6_DST_UNREACH_ADDR: 162 stat->icp6errs_dst_unreach_addr++; 163 return; 164 case ICMP6_DST_UNREACH_NOPORT: 165 stat->icp6errs_dst_unreach_noport++; 166 return; 167 } 168 break; 169 case ICMP6_PACKET_TOO_BIG: 170 stat->icp6errs_packet_too_big++; 171 return; 172 case ICMP6_TIME_EXCEEDED: 173 switch (code) { 174 case ICMP6_TIME_EXCEED_TRANSIT: 175 stat->icp6errs_time_exceed_transit++; 176 return; 177 case ICMP6_TIME_EXCEED_REASSEMBLY: 178 stat->icp6errs_time_exceed_reassembly++; 179 return; 180 } 181 break; 182 case ICMP6_PARAM_PROB: 183 switch (code) { 184 case ICMP6_PARAMPROB_HEADER: 185 stat->icp6errs_paramprob_header++; 186 return; 187 case ICMP6_PARAMPROB_NEXTHEADER: 188 stat->icp6errs_paramprob_nextheader++; 189 return; 190 case ICMP6_PARAMPROB_OPTION: 191 stat->icp6errs_paramprob_option++; 192 return; 193 } 194 break; 195 case ND_REDIRECT: 196 stat->icp6errs_redirect++; 197 return; 198 } 199 stat->icp6errs_unknown++; 200 } 201 202 /* 203 * A wrapper function for icmp6_error() necessary when the erroneous packet 204 * may not contain enough scope zone information. 205 */ 206 void 207 icmp6_error2(m, type, code, param, ifp) 208 struct mbuf *m; 209 int type, code, param; 210 struct ifnet *ifp; 211 { 212 struct ip6_hdr *ip6; 213 214 if (ifp == NULL) 215 return; 216 217 #ifndef PULLDOWN_TEST 218 IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), ); 219 #else 220 if (m->m_len < sizeof(struct ip6_hdr)) { 221 m = m_pullup(m, sizeof(struct ip6_hdr)); 222 if (m == NULL) 223 return; 224 } 225 #endif 226 227 ip6 = mtod(m, struct ip6_hdr *); 228 229 if (in6_setscope(&ip6->ip6_src, ifp, NULL) != 0) 230 return; 231 if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0) 232 return; 233 234 icmp6_error(m, type, code, param); 235 } 236 237 /* 238 * Generate an error packet of type error in response to bad IP6 packet. 239 */ 240 void 241 icmp6_error(m, type, code, param) 242 struct mbuf *m; 243 int type, code, param; 244 { 245 struct ip6_hdr *oip6, *nip6; 246 struct icmp6_hdr *icmp6; 247 u_int preplen; 248 int off; 249 int nxt; 250 251 icmp6stat.icp6s_error++; 252 253 /* count per-type-code statistics */ 254 icmp6_errcount(&icmp6stat.icp6s_outerrhist, type, code); 255 256 #ifdef M_DECRYPTED /*not openbsd*/ 257 if (m->m_flags & M_DECRYPTED) { 258 icmp6stat.icp6s_canterror++; 259 goto freeit; 260 } 261 #endif 262 263 #ifndef PULLDOWN_TEST 264 IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), ); 265 #else 266 if (m->m_len < sizeof(struct ip6_hdr)) { 267 m = m_pullup(m, sizeof(struct ip6_hdr)); 268 if (m == NULL) 269 return; 270 } 271 #endif 272 oip6 = mtod(m, struct ip6_hdr *); 273 274 /* 275 * If the destination address of the erroneous packet is a multicast 276 * address, or the packet was sent using link-layer multicast, 277 * we should basically suppress sending an error (RFC 2463, Section 278 * 2.4). 279 * We have two exceptions (the item e.2 in that section): 280 * - the Pakcet Too Big message can be sent for path MTU discovery. 281 * - the Parameter Problem Message that can be allowed an icmp6 error 282 * in the option type field. This check has been done in 283 * ip6_unknown_opt(), so we can just check the type and code. 284 */ 285 if ((m->m_flags & (M_BCAST|M_MCAST) || 286 IN6_IS_ADDR_MULTICAST(&oip6->ip6_dst)) && 287 (type != ICMP6_PACKET_TOO_BIG && 288 (type != ICMP6_PARAM_PROB || 289 code != ICMP6_PARAMPROB_OPTION))) 290 goto freeit; 291 292 /* 293 * RFC 2463, 2.4 (e.5): source address check. 294 * XXX: the case of anycast source? 295 */ 296 if (IN6_IS_ADDR_UNSPECIFIED(&oip6->ip6_src) || 297 IN6_IS_ADDR_MULTICAST(&oip6->ip6_src)) 298 goto freeit; 299 300 /* 301 * If we are about to send ICMPv6 against ICMPv6 error/redirect, 302 * don't do it. 303 */ 304 nxt = -1; 305 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); 306 if (off >= 0 && nxt == IPPROTO_ICMPV6) { 307 struct icmp6_hdr *icp; 308 309 #ifndef PULLDOWN_TEST 310 IP6_EXTHDR_CHECK(m, 0, off + sizeof(struct icmp6_hdr), ); 311 icp = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 312 #else 313 IP6_EXTHDR_GET(icp, struct icmp6_hdr *, m, off, 314 sizeof(*icp)); 315 if (icp == NULL) { 316 icmp6stat.icp6s_tooshort++; 317 return; 318 } 319 #endif 320 if (icp->icmp6_type < ICMP6_ECHO_REQUEST || 321 icp->icmp6_type == ND_REDIRECT) { 322 /* 323 * ICMPv6 error 324 * Special case: for redirect (which is 325 * informational) we must not send icmp6 error. 326 */ 327 icmp6stat.icp6s_canterror++; 328 goto freeit; 329 } else { 330 /* ICMPv6 informational - send the error */ 331 } 332 } else { 333 /* non-ICMPv6 - send the error */ 334 } 335 336 oip6 = mtod(m, struct ip6_hdr *); /* adjust pointer */ 337 338 /* Finally, do rate limitation check. */ 339 if (icmp6_ratelimit(&oip6->ip6_src, type, code)) { 340 icmp6stat.icp6s_toofreq++; 341 goto freeit; 342 } 343 344 /* 345 * OK, ICMP6 can be generated. 346 */ 347 348 if (m->m_pkthdr.len >= ICMPV6_PLD_MAXLEN) 349 m_adj(m, ICMPV6_PLD_MAXLEN - m->m_pkthdr.len); 350 351 preplen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 352 M_PREPEND(m, preplen, M_DONTWAIT); 353 if (m && m->m_len < preplen) 354 m = m_pullup(m, preplen); 355 if (m == NULL) { 356 nd6log((LOG_DEBUG, "ENOBUFS in icmp6_error %d\n", __LINE__)); 357 return; 358 } 359 360 nip6 = mtod(m, struct ip6_hdr *); 361 nip6->ip6_src = oip6->ip6_src; 362 nip6->ip6_dst = oip6->ip6_dst; 363 364 in6_clearscope(&oip6->ip6_src); 365 in6_clearscope(&oip6->ip6_dst); 366 367 icmp6 = (struct icmp6_hdr *)(nip6 + 1); 368 icmp6->icmp6_type = type; 369 icmp6->icmp6_code = code; 370 icmp6->icmp6_pptr = htonl((u_int32_t)param); 371 372 /* 373 * icmp6_reflect() is designed to be in the input path. 374 * icmp6_error() can be called from both input and output path, 375 * and if we are in output path rcvif could contain bogus value. 376 * clear m->m_pkthdr.rcvif for safety, we should have enough scope 377 * information in ip header (nip6). 378 */ 379 m->m_pkthdr.rcvif = NULL; 380 381 icmp6stat.icp6s_outhist[type]++; 382 icmp6_reflect(m, sizeof(struct ip6_hdr)); /* header order: IPv6 - ICMPv6 */ 383 384 return; 385 386 freeit: 387 /* 388 * If we can't tell whether or not we can generate ICMP6, free it. 389 */ 390 m_freem(m); 391 } 392 393 /* 394 * Process a received ICMP6 message. 395 */ 396 int 397 icmp6_input(mp, offp, proto) 398 struct mbuf **mp; 399 int *offp, proto; 400 { 401 struct mbuf *m = *mp, *n; 402 struct ip6_hdr *ip6, *nip6; 403 struct icmp6_hdr *icmp6, *nicmp6; 404 int off = *offp; 405 int icmp6len = m->m_pkthdr.len - *offp; 406 int code, sum, noff; 407 408 #ifndef PULLDOWN_TEST 409 IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_hdr), IPPROTO_DONE); 410 /* m might change if M_LOOP. So, call mtod after this */ 411 #endif 412 413 /* 414 * Locate icmp6 structure in mbuf, and check 415 * that not corrupted and of at least minimum length 416 */ 417 418 ip6 = mtod(m, struct ip6_hdr *); 419 if (icmp6len < sizeof(struct icmp6_hdr)) { 420 icmp6stat.icp6s_tooshort++; 421 goto freeit; 422 } 423 424 /* 425 * calculate the checksum 426 */ 427 #ifndef PULLDOWN_TEST 428 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off); 429 #else 430 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 431 if (icmp6 == NULL) { 432 icmp6stat.icp6s_tooshort++; 433 return IPPROTO_DONE; 434 } 435 #endif 436 code = icmp6->icmp6_code; 437 438 if ((sum = in6_cksum(m, IPPROTO_ICMPV6, off, icmp6len)) != 0) { 439 nd6log((LOG_ERR, 440 "ICMP6 checksum error(%d|%x) %s\n", 441 icmp6->icmp6_type, sum, ip6_sprintf(&ip6->ip6_src))); 442 icmp6stat.icp6s_checksum++; 443 goto freeit; 444 } 445 446 if (faithprefix_p != NULL && (*faithprefix_p)(&ip6->ip6_dst)) { 447 /* 448 * Deliver very specific ICMP6 type only. 449 * This is important to deliver TOOBIG. Otherwise PMTUD 450 * will not work. 451 */ 452 switch (icmp6->icmp6_type) { 453 case ICMP6_DST_UNREACH: 454 case ICMP6_PACKET_TOO_BIG: 455 case ICMP6_TIME_EXCEEDED: 456 break; 457 default: 458 goto freeit; 459 } 460 } 461 462 icmp6stat.icp6s_inhist[icmp6->icmp6_type]++; 463 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_msg); 464 if (icmp6->icmp6_type < ICMP6_INFOMSG_MASK) 465 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_error); 466 467 switch (icmp6->icmp6_type) { 468 case ICMP6_DST_UNREACH: 469 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_dstunreach); 470 switch (code) { 471 case ICMP6_DST_UNREACH_NOROUTE: 472 code = PRC_UNREACH_NET; 473 break; 474 case ICMP6_DST_UNREACH_ADMIN: 475 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_adminprohib); 476 code = PRC_UNREACH_PROTOCOL; /* is this a good code? */ 477 break; 478 case ICMP6_DST_UNREACH_ADDR: 479 code = PRC_HOSTDEAD; 480 break; 481 case ICMP6_DST_UNREACH_BEYONDSCOPE: 482 /* I mean "source address was incorrect." */ 483 code = PRC_PARAMPROB; 484 break; 485 case ICMP6_DST_UNREACH_NOPORT: 486 code = PRC_UNREACH_PORT; 487 break; 488 default: 489 goto badcode; 490 } 491 goto deliver; 492 break; 493 494 case ICMP6_PACKET_TOO_BIG: 495 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_pkttoobig); 496 497 /* validation is made in icmp6_mtudisc_update */ 498 499 code = PRC_MSGSIZE; 500 501 /* 502 * Updating the path MTU will be done after examining 503 * intermediate extension headers. 504 */ 505 goto deliver; 506 break; 507 508 case ICMP6_TIME_EXCEEDED: 509 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_timeexceed); 510 switch (code) { 511 case ICMP6_TIME_EXCEED_TRANSIT: 512 code = PRC_TIMXCEED_INTRANS; 513 break; 514 case ICMP6_TIME_EXCEED_REASSEMBLY: 515 code = PRC_TIMXCEED_REASS; 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, NULL)) { 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 case NI_QTYPE_IPV4ADDR: 1221 switch (ni6->ni_code) { 1222 case ICMP6_NI_SUBJ_IPV6: 1223 #if ICMP6_NI_SUBJ_IPV6 != 0 1224 case 0: 1225 #endif 1226 /* 1227 * backward compatibility - try to accept 03 draft 1228 * format, where no Subject is present. 1229 */ 1230 if (qtype == NI_QTYPE_FQDN && ni6->ni_code == 0 && 1231 subjlen == 0) { 1232 oldfqdn++; 1233 break; 1234 } 1235 #if ICMP6_NI_SUBJ_IPV6 != 0 1236 if (ni6->ni_code != ICMP6_NI_SUBJ_IPV6) 1237 goto bad; 1238 #endif 1239 1240 if (subjlen != sizeof(struct in6_addr)) 1241 goto bad; 1242 1243 /* 1244 * Validate Subject address. 1245 * 1246 * Not sure what exactly "address belongs to the node" 1247 * means in the spec, is it just unicast, or what? 1248 * 1249 * At this moment we consider Subject address as 1250 * "belong to the node" if the Subject address equals 1251 * to the IPv6 destination address; validation for 1252 * IPv6 destination address should have done enough 1253 * check for us. 1254 * 1255 * We do not do proxy at this moment. 1256 */ 1257 /* m_pulldown instead of copy? */ 1258 m_copydata(m, off + sizeof(struct icmp6_nodeinfo), 1259 subjlen, (caddr_t)&in6_subj); 1260 if (in6_setscope(&in6_subj, m->m_pkthdr.rcvif, NULL)) 1261 goto bad; 1262 1263 subj = (char *)&in6_subj; 1264 if (IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, &in6_subj)) 1265 break; 1266 1267 /* 1268 * XXX if we are to allow other cases, we should really 1269 * be careful about scope here. 1270 * basically, we should disallow queries toward IPv6 1271 * destination X with subject Y, 1272 * if scope(X) > scope(Y). 1273 * if we allow scope(X) > scope(Y), it will result in 1274 * information leakage across scope boundary. 1275 */ 1276 goto bad; 1277 1278 case ICMP6_NI_SUBJ_FQDN: 1279 /* 1280 * Validate Subject name with gethostname(3). 1281 * 1282 * The behavior may need some debate, since: 1283 * - we are not sure if the node has FQDN as 1284 * hostname (returned by gethostname(3)). 1285 * - the code does wildcard match for truncated names. 1286 * however, we are not sure if we want to perform 1287 * wildcard match, if gethostname(3) side has 1288 * truncated hostname. 1289 */ 1290 n = ni6_nametodns(hostname, hostnamelen, 0); 1291 if (!n || n->m_next || n->m_len == 0) 1292 goto bad; 1293 IP6_EXTHDR_GET(subj, char *, m, 1294 off + sizeof(struct icmp6_nodeinfo), subjlen); 1295 if (subj == NULL) 1296 goto bad; 1297 if (!ni6_dnsmatch(subj, subjlen, mtod(n, const char *), 1298 n->m_len)) { 1299 goto bad; 1300 } 1301 m_freem(n); 1302 n = NULL; 1303 break; 1304 1305 case ICMP6_NI_SUBJ_IPV4: /* XXX: to be implemented? */ 1306 default: 1307 goto bad; 1308 } 1309 break; 1310 } 1311 1312 /* refuse based on configuration. XXX ICMP6_NI_REFUSED? */ 1313 switch (qtype) { 1314 case NI_QTYPE_FQDN: 1315 if ((icmp6_nodeinfo & 1) == 0) 1316 goto bad; 1317 break; 1318 case NI_QTYPE_NODEADDR: 1319 case NI_QTYPE_IPV4ADDR: 1320 if ((icmp6_nodeinfo & 2) == 0) 1321 goto bad; 1322 break; 1323 } 1324 1325 /* guess reply length */ 1326 switch (qtype) { 1327 case NI_QTYPE_NOOP: 1328 break; /* no reply data */ 1329 case NI_QTYPE_SUPTYPES: 1330 replylen += sizeof(u_int32_t); 1331 break; 1332 case NI_QTYPE_FQDN: 1333 /* XXX will append an mbuf */ 1334 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1335 break; 1336 case NI_QTYPE_NODEADDR: 1337 addrs = ni6_addrs(ni6, m, &ifp, (struct in6_addr *)subj); 1338 if ((replylen += addrs * (sizeof(struct in6_addr) + 1339 sizeof(u_int32_t))) > MCLBYTES) 1340 replylen = MCLBYTES; /* XXX: will truncate pkt later */ 1341 break; 1342 case NI_QTYPE_IPV4ADDR: 1343 /* unsupported - should respond with unknown Qtype? */ 1344 break; 1345 default: 1346 /* 1347 * XXX: We must return a reply with the ICMP6 code 1348 * `unknown Qtype' in this case. However we regard the case 1349 * as an FQDN query for backward compatibility. 1350 * Older versions set a random value to this field, 1351 * so it rarely varies in the defined qtypes. 1352 * But the mechanism is not reliable... 1353 * maybe we should obsolete older versions. 1354 */ 1355 qtype = NI_QTYPE_FQDN; 1356 /* XXX will append an mbuf */ 1357 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1358 oldfqdn++; 1359 break; 1360 } 1361 1362 /* allocate an mbuf to reply. */ 1363 MGETHDR(n, M_DONTWAIT, m->m_type); 1364 if (n == NULL) { 1365 m_freem(m); 1366 return (NULL); 1367 } 1368 M_MOVE_PKTHDR(n, m); /* just for recvif */ 1369 if (replylen > MHLEN) { 1370 if (replylen > MCLBYTES) { 1371 /* 1372 * XXX: should we try to allocate more? But MCLBYTES 1373 * is probably much larger than IPV6_MMTU... 1374 */ 1375 goto bad; 1376 } 1377 MCLGET(n, M_DONTWAIT); 1378 if ((n->m_flags & M_EXT) == 0) { 1379 goto bad; 1380 } 1381 } 1382 n->m_pkthdr.len = n->m_len = replylen; 1383 1384 /* copy mbuf header and IPv6 + Node Information base headers */ 1385 bcopy(mtod(m, caddr_t), mtod(n, caddr_t), sizeof(struct ip6_hdr)); 1386 nni6 = (struct icmp6_nodeinfo *)(mtod(n, struct ip6_hdr *) + 1); 1387 bcopy((caddr_t)ni6, (caddr_t)nni6, sizeof(struct icmp6_nodeinfo)); 1388 1389 /* qtype dependent procedure */ 1390 switch (qtype) { 1391 case NI_QTYPE_NOOP: 1392 nni6->ni_code = ICMP6_NI_SUCCESS; 1393 nni6->ni_flags = 0; 1394 break; 1395 case NI_QTYPE_SUPTYPES: 1396 { 1397 u_int32_t v; 1398 nni6->ni_code = ICMP6_NI_SUCCESS; 1399 nni6->ni_flags = htons(0x0000); /* raw bitmap */ 1400 /* supports NOOP, SUPTYPES, FQDN, and NODEADDR */ 1401 v = (u_int32_t)htonl(0x0000000f); 1402 bcopy(&v, nni6 + 1, sizeof(u_int32_t)); 1403 break; 1404 } 1405 case NI_QTYPE_FQDN: 1406 nni6->ni_code = ICMP6_NI_SUCCESS; 1407 fqdn = (struct ni_reply_fqdn *)(mtod(n, caddr_t) + 1408 sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo)); 1409 nni6->ni_flags = 0; /* XXX: meaningless TTL */ 1410 fqdn->ni_fqdn_ttl = 0; /* ditto. */ 1411 /* 1412 * XXX do we really have FQDN in variable "hostname"? 1413 */ 1414 n->m_next = ni6_nametodns(hostname, hostnamelen, oldfqdn); 1415 if (n->m_next == NULL) 1416 goto bad; 1417 /* XXX we assume that n->m_next is not a chain */ 1418 if (n->m_next->m_next != NULL) 1419 goto bad; 1420 n->m_pkthdr.len += n->m_next->m_len; 1421 break; 1422 case NI_QTYPE_NODEADDR: 1423 { 1424 int lenlim, copied; 1425 1426 nni6->ni_code = ICMP6_NI_SUCCESS; 1427 n->m_pkthdr.len = n->m_len = 1428 sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo); 1429 lenlim = M_TRAILINGSPACE(n); 1430 copied = ni6_store_addrs(ni6, nni6, ifp, lenlim); 1431 /* XXX: reset mbuf length */ 1432 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) + 1433 sizeof(struct icmp6_nodeinfo) + copied; 1434 break; 1435 } 1436 default: 1437 break; /* XXX impossible! */ 1438 } 1439 1440 nni6->ni_type = ICMP6_NI_REPLY; 1441 m_freem(m); 1442 return (n); 1443 1444 bad: 1445 m_freem(m); 1446 if (n) 1447 m_freem(n); 1448 return (NULL); 1449 } 1450 #undef hostnamelen 1451 1452 /* 1453 * make a mbuf with DNS-encoded string. no compression support. 1454 * 1455 * XXX names with less than 2 dots (like "foo" or "foo.section") will be 1456 * treated as truncated name (two \0 at the end). this is a wild guess. 1457 */ 1458 static struct mbuf * 1459 ni6_nametodns(name, namelen, old) 1460 const char *name; 1461 int namelen; 1462 int old; /* return pascal string if non-zero */ 1463 { 1464 struct mbuf *m; 1465 char *cp, *ep; 1466 const char *p, *q; 1467 int i, len, nterm; 1468 1469 if (old) 1470 len = namelen + 1; 1471 else 1472 len = MCLBYTES; 1473 1474 /* because MAXHOSTNAMELEN is usually 256, we use cluster mbuf */ 1475 MGET(m, M_DONTWAIT, MT_DATA); 1476 if (m && len > MLEN) { 1477 MCLGET(m, M_DONTWAIT); 1478 if ((m->m_flags & M_EXT) == 0) 1479 goto fail; 1480 } 1481 if (!m) 1482 goto fail; 1483 m->m_next = NULL; 1484 1485 if (old) { 1486 m->m_len = len; 1487 *mtod(m, char *) = namelen; 1488 bcopy(name, mtod(m, char *) + 1, namelen); 1489 return m; 1490 } else { 1491 m->m_len = 0; 1492 cp = mtod(m, char *); 1493 ep = mtod(m, char *) + M_TRAILINGSPACE(m); 1494 1495 /* if not certain about my name, return empty buffer */ 1496 if (namelen == 0) 1497 return m; 1498 1499 /* 1500 * guess if it looks like shortened hostname, or FQDN. 1501 * shortened hostname needs two trailing "\0". 1502 */ 1503 i = 0; 1504 for (p = name; p < name + namelen; p++) { 1505 if (*p && *p == '.') 1506 i++; 1507 } 1508 if (i < 2) 1509 nterm = 2; 1510 else 1511 nterm = 1; 1512 1513 p = name; 1514 while (cp < ep && p < name + namelen) { 1515 i = 0; 1516 for (q = p; q < name + namelen && *q && *q != '.'; q++) 1517 i++; 1518 /* result does not fit into mbuf */ 1519 if (cp + i + 1 >= ep) 1520 goto fail; 1521 /* 1522 * DNS label length restriction, RFC1035 page 8. 1523 * "i == 0" case is included here to avoid returning 1524 * 0-length label on "foo..bar". 1525 */ 1526 if (i <= 0 || i >= 64) 1527 goto fail; 1528 *cp++ = i; 1529 bcopy(p, cp, i); 1530 cp += i; 1531 p = q; 1532 if (p < name + namelen && *p == '.') 1533 p++; 1534 } 1535 /* termination */ 1536 if (cp + nterm >= ep) 1537 goto fail; 1538 while (nterm-- > 0) 1539 *cp++ = '\0'; 1540 m->m_len = cp - mtod(m, char *); 1541 return m; 1542 } 1543 1544 panic("should not reach here"); 1545 /* NOTREACHED */ 1546 1547 fail: 1548 if (m) 1549 m_freem(m); 1550 return NULL; 1551 } 1552 1553 /* 1554 * check if two DNS-encoded string matches. takes care of truncated 1555 * form (with \0\0 at the end). no compression support. 1556 * XXX upper/lowercase match (see RFC2065) 1557 */ 1558 static int 1559 ni6_dnsmatch(a, alen, b, blen) 1560 const char *a; 1561 int alen; 1562 const char *b; 1563 int blen; 1564 { 1565 const char *a0, *b0; 1566 int l; 1567 1568 /* simplest case - need validation? */ 1569 if (alen == blen && bcmp(a, b, alen) == 0) 1570 return 1; 1571 1572 a0 = a; 1573 b0 = b; 1574 1575 /* termination is mandatory */ 1576 if (alen < 2 || blen < 2) 1577 return 0; 1578 if (a0[alen - 1] != '\0' || b0[blen - 1] != '\0') 1579 return 0; 1580 alen--; 1581 blen--; 1582 1583 while (a - a0 < alen && b - b0 < blen) { 1584 if (a - a0 + 1 > alen || b - b0 + 1 > blen) 1585 return 0; 1586 1587 if ((signed char)a[0] < 0 || (signed char)b[0] < 0) 1588 return 0; 1589 /* we don't support compression yet */ 1590 if (a[0] >= 64 || b[0] >= 64) 1591 return 0; 1592 1593 /* truncated case */ 1594 if (a[0] == 0 && a - a0 == alen - 1) 1595 return 1; 1596 if (b[0] == 0 && b - b0 == blen - 1) 1597 return 1; 1598 if (a[0] == 0 || b[0] == 0) 1599 return 0; 1600 1601 if (a[0] != b[0]) 1602 return 0; 1603 l = a[0]; 1604 if (a - a0 + 1 + l > alen || b - b0 + 1 + l > blen) 1605 return 0; 1606 if (bcmp(a + 1, b + 1, l) != 0) 1607 return 0; 1608 1609 a += 1 + l; 1610 b += 1 + l; 1611 } 1612 1613 if (a - a0 == alen && b - b0 == blen) 1614 return 1; 1615 else 1616 return 0; 1617 } 1618 1619 /* 1620 * calculate the number of addresses to be returned in the node info reply. 1621 */ 1622 static int 1623 ni6_addrs(ni6, m, ifpp, subj) 1624 struct icmp6_nodeinfo *ni6; 1625 struct mbuf *m; 1626 struct ifnet **ifpp; 1627 struct in6_addr *subj; 1628 { 1629 struct ifnet *ifp; 1630 struct in6_ifaddr *ifa6; 1631 struct ifaddr *ifa; 1632 int addrs = 0, addrsofif, iffound = 0; 1633 int niflags = ni6->ni_flags; 1634 1635 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0) { 1636 switch (ni6->ni_code) { 1637 case ICMP6_NI_SUBJ_IPV6: 1638 if (subj == NULL) /* must be impossible... */ 1639 return (0); 1640 break; 1641 default: 1642 /* 1643 * XXX: we only support IPv6 subject address for 1644 * this Qtype. 1645 */ 1646 return (0); 1647 } 1648 } 1649 1650 IFNET_RLOCK(); 1651 for (ifp = TAILQ_FIRST(&ifnet); ifp; ifp = TAILQ_NEXT(ifp, if_list)) { 1652 addrsofif = 0; 1653 TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list) { 1654 if (ifa->ifa_addr->sa_family != AF_INET6) 1655 continue; 1656 ifa6 = (struct in6_ifaddr *)ifa; 1657 1658 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0 && 1659 IN6_ARE_ADDR_EQUAL(subj, &ifa6->ia_addr.sin6_addr)) 1660 iffound = 1; 1661 1662 /* 1663 * IPv4-mapped addresses can only be returned by a 1664 * Node Information proxy, since they represent 1665 * addresses of IPv4-only nodes, which perforce do 1666 * not implement this protocol. 1667 * [icmp-name-lookups-07, Section 5.4] 1668 * So we don't support NI_NODEADDR_FLAG_COMPAT in 1669 * this function at this moment. 1670 */ 1671 1672 /* What do we have to do about ::1? */ 1673 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1674 case IPV6_ADDR_SCOPE_LINKLOCAL: 1675 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0) 1676 continue; 1677 break; 1678 case IPV6_ADDR_SCOPE_SITELOCAL: 1679 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0) 1680 continue; 1681 break; 1682 case IPV6_ADDR_SCOPE_GLOBAL: 1683 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0) 1684 continue; 1685 break; 1686 default: 1687 continue; 1688 } 1689 1690 /* 1691 * check if anycast is okay. 1692 * XXX: just experimental. not in the spec. 1693 */ 1694 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 && 1695 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0) 1696 continue; /* we need only unicast addresses */ 1697 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 1698 (icmp6_nodeinfo & 4) == 0) { 1699 continue; 1700 } 1701 addrsofif++; /* count the address */ 1702 } 1703 if (iffound) { 1704 *ifpp = ifp; 1705 IFNET_RUNLOCK(); 1706 return (addrsofif); 1707 } 1708 1709 addrs += addrsofif; 1710 } 1711 IFNET_RUNLOCK(); 1712 1713 return (addrs); 1714 } 1715 1716 static int 1717 ni6_store_addrs(ni6, nni6, ifp0, resid) 1718 struct icmp6_nodeinfo *ni6, *nni6; 1719 struct ifnet *ifp0; 1720 int resid; 1721 { 1722 struct ifnet *ifp = ifp0 ? ifp0 : TAILQ_FIRST(&ifnet); 1723 struct in6_ifaddr *ifa6; 1724 struct ifaddr *ifa; 1725 struct ifnet *ifp_dep = NULL; 1726 int copied = 0, allow_deprecated = 0; 1727 u_char *cp = (u_char *)(nni6 + 1); 1728 int niflags = ni6->ni_flags; 1729 u_int32_t ltime; 1730 1731 if (ifp0 == NULL && !(niflags & NI_NODEADDR_FLAG_ALL)) 1732 return (0); /* needless to copy */ 1733 1734 IFNET_RLOCK(); 1735 again: 1736 1737 for (; ifp; ifp = TAILQ_NEXT(ifp, if_list)) { 1738 for (ifa = ifp->if_addrlist.tqh_first; ifa; 1739 ifa = ifa->ifa_list.tqe_next) { 1740 if (ifa->ifa_addr->sa_family != AF_INET6) 1741 continue; 1742 ifa6 = (struct in6_ifaddr *)ifa; 1743 1744 if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) != 0 && 1745 allow_deprecated == 0) { 1746 /* 1747 * prefererred address should be put before 1748 * deprecated addresses. 1749 */ 1750 1751 /* record the interface for later search */ 1752 if (ifp_dep == NULL) 1753 ifp_dep = ifp; 1754 1755 continue; 1756 } else if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) == 0 && 1757 allow_deprecated != 0) 1758 continue; /* we now collect deprecated addrs */ 1759 1760 /* What do we have to do about ::1? */ 1761 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1762 case IPV6_ADDR_SCOPE_LINKLOCAL: 1763 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0) 1764 continue; 1765 break; 1766 case IPV6_ADDR_SCOPE_SITELOCAL: 1767 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0) 1768 continue; 1769 break; 1770 case IPV6_ADDR_SCOPE_GLOBAL: 1771 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0) 1772 continue; 1773 break; 1774 default: 1775 continue; 1776 } 1777 1778 /* 1779 * check if anycast is okay. 1780 * XXX: just experimental. not in the spec. 1781 */ 1782 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 && 1783 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0) 1784 continue; 1785 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 1786 (icmp6_nodeinfo & 4) == 0) { 1787 continue; 1788 } 1789 1790 /* now we can copy the address */ 1791 if (resid < sizeof(struct in6_addr) + 1792 sizeof(u_int32_t)) { 1793 /* 1794 * We give up much more copy. 1795 * Set the truncate flag and return. 1796 */ 1797 nni6->ni_flags |= NI_NODEADDR_FLAG_TRUNCATE; 1798 IFNET_RUNLOCK(); 1799 return (copied); 1800 } 1801 1802 /* 1803 * Set the TTL of the address. 1804 * The TTL value should be one of the following 1805 * according to the specification: 1806 * 1807 * 1. The remaining lifetime of a DHCP lease on the 1808 * address, or 1809 * 2. The remaining Valid Lifetime of a prefix from 1810 * which the address was derived through Stateless 1811 * Autoconfiguration. 1812 * 1813 * Note that we currently do not support stateful 1814 * address configuration by DHCPv6, so the former 1815 * case can't happen. 1816 */ 1817 if (ifa6->ia6_lifetime.ia6t_expire == 0) 1818 ltime = ND6_INFINITE_LIFETIME; 1819 else { 1820 if (ifa6->ia6_lifetime.ia6t_expire > 1821 time_second) 1822 ltime = htonl(ifa6->ia6_lifetime.ia6t_expire - time_second); 1823 else 1824 ltime = 0; 1825 } 1826 1827 bcopy(<ime, cp, sizeof(u_int32_t)); 1828 cp += sizeof(u_int32_t); 1829 1830 /* copy the address itself */ 1831 bcopy(&ifa6->ia_addr.sin6_addr, cp, 1832 sizeof(struct in6_addr)); 1833 in6_clearscope((struct in6_addr *)cp); /* XXX */ 1834 cp += sizeof(struct in6_addr); 1835 1836 resid -= (sizeof(struct in6_addr) + sizeof(u_int32_t)); 1837 copied += (sizeof(struct in6_addr) + sizeof(u_int32_t)); 1838 } 1839 if (ifp0) /* we need search only on the specified IF */ 1840 break; 1841 } 1842 1843 if (allow_deprecated == 0 && ifp_dep != NULL) { 1844 ifp = ifp_dep; 1845 allow_deprecated = 1; 1846 1847 goto again; 1848 } 1849 1850 IFNET_RUNLOCK(); 1851 1852 return (copied); 1853 } 1854 1855 /* 1856 * XXX almost dup'ed code with rip6_input. 1857 */ 1858 static int 1859 icmp6_rip6_input(mp, off) 1860 struct mbuf **mp; 1861 int off; 1862 { 1863 struct mbuf *m = *mp; 1864 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1865 struct in6pcb *in6p; 1866 struct in6pcb *last = NULL; 1867 struct sockaddr_in6 fromsa; 1868 struct icmp6_hdr *icmp6; 1869 struct mbuf *opts = NULL; 1870 1871 #ifndef PULLDOWN_TEST 1872 /* this is assumed to be safe. */ 1873 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off); 1874 #else 1875 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 1876 if (icmp6 == NULL) { 1877 /* m is already reclaimed */ 1878 return (IPPROTO_DONE); 1879 } 1880 #endif 1881 1882 /* 1883 * XXX: the address may have embedded scope zone ID, which should be 1884 * hidden from applications. 1885 */ 1886 bzero(&fromsa, sizeof(fromsa)); 1887 fromsa.sin6_family = AF_INET6; 1888 fromsa.sin6_len = sizeof(struct sockaddr_in6); 1889 fromsa.sin6_addr = ip6->ip6_src; 1890 if (sa6_recoverscope(&fromsa)) { 1891 m_freem(m); 1892 return (IPPROTO_DONE); 1893 } 1894 1895 INP_INFO_RLOCK(&ripcbinfo); 1896 LIST_FOREACH(in6p, &ripcb, inp_list) { 1897 INP_LOCK(in6p); 1898 if ((in6p->inp_vflag & INP_IPV6) == 0) { 1899 docontinue: 1900 INP_UNLOCK(in6p); 1901 continue; 1902 } 1903 if (in6p->in6p_ip6_nxt != IPPROTO_ICMPV6) 1904 goto docontinue; 1905 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr) && 1906 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr, &ip6->ip6_dst)) 1907 goto docontinue; 1908 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr) && 1909 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr, &ip6->ip6_src)) 1910 goto docontinue; 1911 if (in6p->in6p_icmp6filt 1912 && ICMP6_FILTER_WILLBLOCK(icmp6->icmp6_type, 1913 in6p->in6p_icmp6filt)) 1914 goto docontinue; 1915 if (last) { 1916 struct mbuf *n = NULL; 1917 1918 /* 1919 * Recent network drivers tend to allocate a single 1920 * mbuf cluster, rather than to make a couple of 1921 * mbufs without clusters. Also, since the IPv6 code 1922 * path tries to avoid m_pullup(), it is highly 1923 * probable that we still have an mbuf cluster here 1924 * even though the necessary length can be stored in an 1925 * mbuf's internal buffer. 1926 * Meanwhile, the default size of the receive socket 1927 * buffer for raw sockets is not so large. This means 1928 * the possibility of packet loss is relatively higher 1929 * than before. To avoid this scenario, we copy the 1930 * received data to a separate mbuf that does not use 1931 * a cluster, if possible. 1932 * XXX: it is better to copy the data after stripping 1933 * intermediate headers. 1934 */ 1935 if ((m->m_flags & M_EXT) && m->m_next == NULL && 1936 m->m_len <= MHLEN) { 1937 MGET(n, M_DONTWAIT, m->m_type); 1938 if (n != NULL) { 1939 if (m_dup_pkthdr(n, m, M_NOWAIT)) { 1940 bcopy(m->m_data, n->m_data, 1941 m->m_len); 1942 n->m_len = m->m_len; 1943 } else { 1944 m_free(n); 1945 n = NULL; 1946 } 1947 } 1948 } 1949 if (n != NULL || 1950 (n = m_copy(m, 0, (int)M_COPYALL)) != NULL) { 1951 if (last->in6p_flags & IN6P_CONTROLOPTS) 1952 ip6_savecontrol(last, n, &opts); 1953 /* strip intermediate headers */ 1954 m_adj(n, off); 1955 SOCKBUF_LOCK(&last->in6p_socket->so_rcv); 1956 if (sbappendaddr_locked( 1957 &last->in6p_socket->so_rcv, 1958 (struct sockaddr *)&fromsa, n, opts) 1959 == 0) { 1960 /* should notify about lost packet */ 1961 m_freem(n); 1962 if (opts) { 1963 m_freem(opts); 1964 } 1965 SOCKBUF_UNLOCK( 1966 &last->in6p_socket->so_rcv); 1967 } else 1968 sorwakeup_locked(last->in6p_socket); 1969 opts = NULL; 1970 } 1971 INP_UNLOCK(last); 1972 } 1973 last = in6p; 1974 } 1975 if (last) { 1976 if (last->in6p_flags & IN6P_CONTROLOPTS) 1977 ip6_savecontrol(last, m, &opts); 1978 /* strip intermediate headers */ 1979 m_adj(m, off); 1980 1981 /* avoid using mbuf clusters if possible (see above) */ 1982 if ((m->m_flags & M_EXT) && m->m_next == NULL && 1983 m->m_len <= MHLEN) { 1984 struct mbuf *n; 1985 1986 MGET(n, M_DONTWAIT, m->m_type); 1987 if (n != NULL) { 1988 if (m_dup_pkthdr(n, m, M_NOWAIT)) { 1989 bcopy(m->m_data, n->m_data, m->m_len); 1990 n->m_len = m->m_len; 1991 1992 m_freem(m); 1993 m = n; 1994 } else { 1995 m_freem(n); 1996 n = NULL; 1997 } 1998 } 1999 } 2000 SOCKBUF_LOCK(&last->in6p_socket->so_rcv); 2001 if (sbappendaddr_locked(&last->in6p_socket->so_rcv, 2002 (struct sockaddr *)&fromsa, m, opts) == 0) { 2003 m_freem(m); 2004 if (opts) 2005 m_freem(opts); 2006 SOCKBUF_UNLOCK(&last->in6p_socket->so_rcv); 2007 } else 2008 sorwakeup_locked(last->in6p_socket); 2009 INP_UNLOCK(last); 2010 } else { 2011 m_freem(m); 2012 ip6stat.ip6s_delivered--; 2013 } 2014 INP_INFO_RUNLOCK(&ripcbinfo); 2015 return IPPROTO_DONE; 2016 } 2017 2018 /* 2019 * Reflect the ip6 packet back to the source. 2020 * OFF points to the icmp6 header, counted from the top of the mbuf. 2021 */ 2022 void 2023 icmp6_reflect(m, off) 2024 struct mbuf *m; 2025 size_t off; 2026 { 2027 struct ip6_hdr *ip6; 2028 struct icmp6_hdr *icmp6; 2029 struct in6_ifaddr *ia; 2030 int plen; 2031 int type, code; 2032 struct ifnet *outif = NULL; 2033 struct in6_addr origdst, *src = NULL; 2034 2035 /* too short to reflect */ 2036 if (off < sizeof(struct ip6_hdr)) { 2037 nd6log((LOG_DEBUG, 2038 "sanity fail: off=%lx, sizeof(ip6)=%lx in %s:%d\n", 2039 (u_long)off, (u_long)sizeof(struct ip6_hdr), 2040 __FILE__, __LINE__)); 2041 goto bad; 2042 } 2043 2044 /* 2045 * If there are extra headers between IPv6 and ICMPv6, strip 2046 * off that header first. 2047 */ 2048 #ifdef DIAGNOSTIC 2049 if (sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) > MHLEN) 2050 panic("assumption failed in icmp6_reflect"); 2051 #endif 2052 if (off > sizeof(struct ip6_hdr)) { 2053 size_t l; 2054 struct ip6_hdr nip6; 2055 2056 l = off - sizeof(struct ip6_hdr); 2057 m_copydata(m, 0, sizeof(nip6), (caddr_t)&nip6); 2058 m_adj(m, l); 2059 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 2060 if (m->m_len < l) { 2061 if ((m = m_pullup(m, l)) == NULL) 2062 return; 2063 } 2064 bcopy((caddr_t)&nip6, mtod(m, caddr_t), sizeof(nip6)); 2065 } else /* off == sizeof(struct ip6_hdr) */ { 2066 size_t l; 2067 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 2068 if (m->m_len < l) { 2069 if ((m = m_pullup(m, l)) == NULL) 2070 return; 2071 } 2072 } 2073 plen = m->m_pkthdr.len - sizeof(struct ip6_hdr); 2074 ip6 = mtod(m, struct ip6_hdr *); 2075 ip6->ip6_nxt = IPPROTO_ICMPV6; 2076 icmp6 = (struct icmp6_hdr *)(ip6 + 1); 2077 type = icmp6->icmp6_type; /* keep type for statistics */ 2078 code = icmp6->icmp6_code; /* ditto. */ 2079 2080 origdst = ip6->ip6_dst; 2081 /* 2082 * ip6_input() drops a packet if its src is multicast. 2083 * So, the src is never multicast. 2084 */ 2085 ip6->ip6_dst = ip6->ip6_src; 2086 2087 /* 2088 * If the incoming packet was addressed directly to us (i.e. unicast), 2089 * use dst as the src for the reply. 2090 * The IN6_IFF_NOTREADY case should be VERY rare, but is possible 2091 * (for example) when we encounter an error while forwarding procedure 2092 * destined to a duplicated address of ours. 2093 * Note that ip6_getdstifaddr() may fail if we are in an error handling 2094 * procedure of an outgoing packet of our own, in which case we need 2095 * to search in the ifaddr list. 2096 */ 2097 if (!IN6_IS_ADDR_MULTICAST(&origdst)) { 2098 if ((ia = ip6_getdstifaddr(m))) { 2099 if (!(ia->ia6_flags & 2100 (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY))) 2101 src = &ia->ia_addr.sin6_addr; 2102 } else { 2103 struct sockaddr_in6 d; 2104 2105 bzero(&d, sizeof(d)); 2106 d.sin6_family = AF_INET6; 2107 d.sin6_len = sizeof(d); 2108 d.sin6_addr = origdst; 2109 ia = (struct in6_ifaddr *) 2110 ifa_ifwithaddr((struct sockaddr *)&d); 2111 if (ia && 2112 !(ia->ia6_flags & 2113 (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY))) { 2114 src = &ia->ia_addr.sin6_addr; 2115 } 2116 } 2117 } 2118 2119 if (src == NULL) { 2120 int e; 2121 struct sockaddr_in6 sin6; 2122 struct route_in6 ro; 2123 2124 /* 2125 * This case matches to multicasts, our anycast, or unicasts 2126 * that we do not own. Select a source address based on the 2127 * source address of the erroneous packet. 2128 */ 2129 bzero(&sin6, sizeof(sin6)); 2130 sin6.sin6_family = AF_INET6; 2131 sin6.sin6_len = sizeof(sin6); 2132 sin6.sin6_addr = ip6->ip6_dst; /* zone ID should be embedded */ 2133 2134 bzero(&ro, sizeof(ro)); 2135 src = in6_selectsrc(&sin6, NULL, NULL, &ro, NULL, &outif, &e); 2136 if (ro.ro_rt) 2137 RTFREE(ro.ro_rt); /* XXX: we could use this */ 2138 if (src == NULL) { 2139 nd6log((LOG_DEBUG, 2140 "icmp6_reflect: source can't be determined: " 2141 "dst=%s, error=%d\n", 2142 ip6_sprintf(&sin6.sin6_addr), e)); 2143 goto bad; 2144 } 2145 } 2146 2147 ip6->ip6_src = *src; 2148 ip6->ip6_flow = 0; 2149 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2150 ip6->ip6_vfc |= IPV6_VERSION; 2151 ip6->ip6_nxt = IPPROTO_ICMPV6; 2152 if (outif) 2153 ip6->ip6_hlim = ND_IFINFO(outif)->chlim; 2154 else if (m->m_pkthdr.rcvif) { 2155 /* XXX: This may not be the outgoing interface */ 2156 ip6->ip6_hlim = ND_IFINFO(m->m_pkthdr.rcvif)->chlim; 2157 } else 2158 ip6->ip6_hlim = ip6_defhlim; 2159 2160 icmp6->icmp6_cksum = 0; 2161 icmp6->icmp6_cksum = in6_cksum(m, IPPROTO_ICMPV6, 2162 sizeof(struct ip6_hdr), plen); 2163 2164 /* 2165 * XXX option handling 2166 */ 2167 2168 m->m_flags &= ~(M_BCAST|M_MCAST); 2169 2170 ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL); 2171 if (outif) 2172 icmp6_ifoutstat_inc(outif, type, code); 2173 2174 return; 2175 2176 bad: 2177 m_freem(m); 2178 return; 2179 } 2180 2181 void 2182 icmp6_fasttimo() 2183 { 2184 2185 return; 2186 } 2187 2188 static const char * 2189 icmp6_redirect_diag(src6, dst6, tgt6) 2190 struct in6_addr *src6; 2191 struct in6_addr *dst6; 2192 struct in6_addr *tgt6; 2193 { 2194 static char buf[1024]; 2195 snprintf(buf, sizeof(buf), "(src=%s dst=%s tgt=%s)", 2196 ip6_sprintf(src6), ip6_sprintf(dst6), ip6_sprintf(tgt6)); 2197 return buf; 2198 } 2199 2200 void 2201 icmp6_redirect_input(m, off) 2202 struct mbuf *m; 2203 int off; 2204 { 2205 struct ifnet *ifp = m->m_pkthdr.rcvif; 2206 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 2207 struct nd_redirect *nd_rd; 2208 int icmp6len = ntohs(ip6->ip6_plen); 2209 char *lladdr = NULL; 2210 int lladdrlen = 0; 2211 u_char *redirhdr = NULL; 2212 int redirhdrlen = 0; 2213 struct rtentry *rt = NULL; 2214 int is_router; 2215 int is_onlink; 2216 struct in6_addr src6 = ip6->ip6_src; 2217 struct in6_addr redtgt6; 2218 struct in6_addr reddst6; 2219 union nd_opts ndopts; 2220 2221 if (!m || !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(&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(&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(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(&redtgt6), ifp->if_addrlen, lladdrlen - 2, 2352 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2353 goto bad; 2354 } 2355 2356 /* RFC 2461 8.3 */ 2357 nd6_cache_lladdr(ifp, &redtgt6, lladdr, lladdrlen, ND_REDIRECT, 2358 is_onlink ? ND_REDIRECT_ONLINK : ND_REDIRECT_ROUTER); 2359 2360 if (!is_onlink) { /* better router case. perform rtredirect. */ 2361 /* perform rtredirect */ 2362 struct sockaddr_in6 sdst; 2363 struct sockaddr_in6 sgw; 2364 struct sockaddr_in6 ssrc; 2365 2366 bzero(&sdst, sizeof(sdst)); 2367 bzero(&sgw, sizeof(sgw)); 2368 bzero(&ssrc, sizeof(ssrc)); 2369 sdst.sin6_family = sgw.sin6_family = ssrc.sin6_family = AF_INET6; 2370 sdst.sin6_len = sgw.sin6_len = ssrc.sin6_len = 2371 sizeof(struct sockaddr_in6); 2372 bcopy(&redtgt6, &sgw.sin6_addr, sizeof(struct in6_addr)); 2373 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2374 bcopy(&src6, &ssrc.sin6_addr, sizeof(struct in6_addr)); 2375 rtredirect((struct sockaddr *)&sdst, (struct sockaddr *)&sgw, 2376 (struct sockaddr *)NULL, RTF_GATEWAY | RTF_HOST, 2377 (struct sockaddr *)&ssrc); 2378 } 2379 /* finally update cached route in each socket via pfctlinput */ 2380 { 2381 struct sockaddr_in6 sdst; 2382 2383 bzero(&sdst, sizeof(sdst)); 2384 sdst.sin6_family = AF_INET6; 2385 sdst.sin6_len = sizeof(struct sockaddr_in6); 2386 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2387 pfctlinput(PRC_REDIRECT_HOST, (struct sockaddr *)&sdst); 2388 #if defined(IPSEC) || defined(FAST_IPSEC) 2389 key_sa_routechange((struct sockaddr *)&sdst); 2390 #endif 2391 } 2392 2393 freeit: 2394 m_freem(m); 2395 return; 2396 2397 bad: 2398 icmp6stat.icp6s_badredirect++; 2399 m_freem(m); 2400 } 2401 2402 void 2403 icmp6_redirect_output(m0, rt) 2404 struct mbuf *m0; 2405 struct rtentry *rt; 2406 { 2407 struct ifnet *ifp; /* my outgoing interface */ 2408 struct in6_addr *ifp_ll6; 2409 struct in6_addr *router_ll6; 2410 struct ip6_hdr *sip6; /* m0 as struct ip6_hdr */ 2411 struct mbuf *m = NULL; /* newly allocated one */ 2412 struct ip6_hdr *ip6; /* m as struct ip6_hdr */ 2413 struct nd_redirect *nd_rd; 2414 size_t maxlen; 2415 u_char *p; 2416 struct ifnet *outif = NULL; 2417 struct sockaddr_in6 src_sa; 2418 2419 icmp6_errcount(&icmp6stat.icp6s_outerrhist, ND_REDIRECT, 0); 2420 2421 /* if we are not router, we don't send icmp6 redirect */ 2422 if (!ip6_forwarding) 2423 goto fail; 2424 2425 /* sanity check */ 2426 if (!m0 || !rt || !(rt->rt_flags & RTF_UP) || !(ifp = rt->rt_ifp)) 2427 goto fail; 2428 2429 /* 2430 * Address check: 2431 * the source address must identify a neighbor, and 2432 * the destination address must not be a multicast address 2433 * [RFC 2461, sec 8.2] 2434 */ 2435 sip6 = mtod(m0, struct ip6_hdr *); 2436 bzero(&src_sa, sizeof(src_sa)); 2437 src_sa.sin6_family = AF_INET6; 2438 src_sa.sin6_len = sizeof(src_sa); 2439 src_sa.sin6_addr = sip6->ip6_src; 2440 if (nd6_is_addr_neighbor(&src_sa, ifp) == 0) 2441 goto fail; 2442 if (IN6_IS_ADDR_MULTICAST(&sip6->ip6_dst)) 2443 goto fail; /* what should we do here? */ 2444 2445 /* rate limit */ 2446 if (icmp6_ratelimit(&sip6->ip6_src, ND_REDIRECT, 0)) 2447 goto fail; 2448 2449 /* 2450 * Since we are going to append up to 1280 bytes (= IPV6_MMTU), 2451 * we almost always ask for an mbuf cluster for simplicity. 2452 * (MHLEN < IPV6_MMTU is almost always true) 2453 */ 2454 #if IPV6_MMTU >= MCLBYTES 2455 # error assumption failed about IPV6_MMTU and MCLBYTES 2456 #endif 2457 MGETHDR(m, M_DONTWAIT, MT_HEADER); 2458 if (m && IPV6_MMTU >= MHLEN) 2459 MCLGET(m, M_DONTWAIT); 2460 if (!m) 2461 goto fail; 2462 m->m_pkthdr.rcvif = NULL; 2463 m->m_len = 0; 2464 maxlen = M_TRAILINGSPACE(m); 2465 maxlen = min(IPV6_MMTU, maxlen); 2466 /* just for safety */ 2467 if (maxlen < sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) + 2468 ((sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7)) { 2469 goto fail; 2470 } 2471 2472 { 2473 /* get ip6 linklocal address for ifp(my outgoing interface). */ 2474 struct in6_ifaddr *ia; 2475 if ((ia = in6ifa_ifpforlinklocal(ifp, 2476 IN6_IFF_NOTREADY| 2477 IN6_IFF_ANYCAST)) == NULL) 2478 goto fail; 2479 ifp_ll6 = &ia->ia_addr.sin6_addr; 2480 } 2481 2482 /* get ip6 linklocal address for the router. */ 2483 if (rt->rt_gateway && (rt->rt_flags & RTF_GATEWAY)) { 2484 struct sockaddr_in6 *sin6; 2485 sin6 = (struct sockaddr_in6 *)rt->rt_gateway; 2486 router_ll6 = &sin6->sin6_addr; 2487 if (!IN6_IS_ADDR_LINKLOCAL(router_ll6)) 2488 router_ll6 = (struct in6_addr *)NULL; 2489 } else 2490 router_ll6 = (struct in6_addr *)NULL; 2491 2492 /* ip6 */ 2493 ip6 = mtod(m, struct ip6_hdr *); 2494 ip6->ip6_flow = 0; 2495 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2496 ip6->ip6_vfc |= IPV6_VERSION; 2497 /* ip6->ip6_plen will be set later */ 2498 ip6->ip6_nxt = IPPROTO_ICMPV6; 2499 ip6->ip6_hlim = 255; 2500 /* ip6->ip6_src must be linklocal addr for my outgoing if. */ 2501 bcopy(ifp_ll6, &ip6->ip6_src, sizeof(struct in6_addr)); 2502 bcopy(&sip6->ip6_src, &ip6->ip6_dst, sizeof(struct in6_addr)); 2503 2504 /* ND Redirect */ 2505 nd_rd = (struct nd_redirect *)(ip6 + 1); 2506 nd_rd->nd_rd_type = ND_REDIRECT; 2507 nd_rd->nd_rd_code = 0; 2508 nd_rd->nd_rd_reserved = 0; 2509 if (rt->rt_flags & RTF_GATEWAY) { 2510 /* 2511 * nd_rd->nd_rd_target must be a link-local address in 2512 * better router cases. 2513 */ 2514 if (!router_ll6) 2515 goto fail; 2516 bcopy(router_ll6, &nd_rd->nd_rd_target, 2517 sizeof(nd_rd->nd_rd_target)); 2518 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2519 sizeof(nd_rd->nd_rd_dst)); 2520 } else { 2521 /* make sure redtgt == reddst */ 2522 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_target, 2523 sizeof(nd_rd->nd_rd_target)); 2524 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2525 sizeof(nd_rd->nd_rd_dst)); 2526 } 2527 2528 p = (u_char *)(nd_rd + 1); 2529 2530 if (!router_ll6) 2531 goto nolladdropt; 2532 2533 { 2534 /* target lladdr option */ 2535 struct rtentry *rt_router = NULL; 2536 int len; 2537 struct sockaddr_dl *sdl; 2538 struct nd_opt_hdr *nd_opt; 2539 char *lladdr; 2540 2541 rt_router = nd6_lookup(router_ll6, 0, ifp); 2542 if (!rt_router) 2543 goto nolladdropt; 2544 len = sizeof(*nd_opt) + ifp->if_addrlen; 2545 len = (len + 7) & ~7; /* round by 8 */ 2546 /* safety check */ 2547 if (len + (p - (u_char *)ip6) > maxlen) 2548 goto nolladdropt; 2549 if (!(rt_router->rt_flags & RTF_GATEWAY) && 2550 (rt_router->rt_flags & RTF_LLINFO) && 2551 (rt_router->rt_gateway->sa_family == AF_LINK) && 2552 (sdl = (struct sockaddr_dl *)rt_router->rt_gateway) && 2553 sdl->sdl_alen) { 2554 nd_opt = (struct nd_opt_hdr *)p; 2555 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 2556 nd_opt->nd_opt_len = len >> 3; 2557 lladdr = (char *)(nd_opt + 1); 2558 bcopy(LLADDR(sdl), lladdr, ifp->if_addrlen); 2559 p += len; 2560 } 2561 } 2562 nolladdropt:; 2563 2564 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2565 2566 /* just to be safe */ 2567 #ifdef M_DECRYPTED /*not openbsd*/ 2568 if (m0->m_flags & M_DECRYPTED) 2569 goto noredhdropt; 2570 #endif 2571 if (p - (u_char *)ip6 > maxlen) 2572 goto noredhdropt; 2573 2574 { 2575 /* redirected header option */ 2576 int len; 2577 struct nd_opt_rd_hdr *nd_opt_rh; 2578 2579 /* 2580 * compute the maximum size for icmp6 redirect header option. 2581 * XXX room for auth header? 2582 */ 2583 len = maxlen - (p - (u_char *)ip6); 2584 len &= ~7; 2585 2586 /* This is just for simplicity. */ 2587 if (m0->m_pkthdr.len != m0->m_len) { 2588 if (m0->m_next) { 2589 m_freem(m0->m_next); 2590 m0->m_next = NULL; 2591 } 2592 m0->m_pkthdr.len = m0->m_len; 2593 } 2594 2595 /* 2596 * Redirected header option spec (RFC2461 4.6.3) talks nothing 2597 * about padding/truncate rule for the original IP packet. 2598 * From the discussion on IPv6imp in Feb 1999, 2599 * the consensus was: 2600 * - "attach as much as possible" is the goal 2601 * - pad if not aligned (original size can be guessed by 2602 * original ip6 header) 2603 * Following code adds the padding if it is simple enough, 2604 * and truncates if not. 2605 */ 2606 if (m0->m_next || m0->m_pkthdr.len != m0->m_len) 2607 panic("assumption failed in %s:%d", __FILE__, 2608 __LINE__); 2609 2610 if (len - sizeof(*nd_opt_rh) < m0->m_pkthdr.len) { 2611 /* not enough room, truncate */ 2612 m0->m_pkthdr.len = m0->m_len = len - 2613 sizeof(*nd_opt_rh); 2614 } else { 2615 /* enough room, pad or truncate */ 2616 size_t extra; 2617 2618 extra = m0->m_pkthdr.len % 8; 2619 if (extra) { 2620 /* pad if easy enough, truncate if not */ 2621 if (8 - extra <= M_TRAILINGSPACE(m0)) { 2622 /* pad */ 2623 m0->m_len += (8 - extra); 2624 m0->m_pkthdr.len += (8 - extra); 2625 } else { 2626 /* truncate */ 2627 m0->m_pkthdr.len -= extra; 2628 m0->m_len -= extra; 2629 } 2630 } 2631 len = m0->m_pkthdr.len + sizeof(*nd_opt_rh); 2632 m0->m_pkthdr.len = m0->m_len = len - 2633 sizeof(*nd_opt_rh); 2634 } 2635 2636 nd_opt_rh = (struct nd_opt_rd_hdr *)p; 2637 bzero(nd_opt_rh, sizeof(*nd_opt_rh)); 2638 nd_opt_rh->nd_opt_rh_type = ND_OPT_REDIRECTED_HEADER; 2639 nd_opt_rh->nd_opt_rh_len = len >> 3; 2640 p += sizeof(*nd_opt_rh); 2641 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2642 2643 /* connect m0 to m */ 2644 m_tag_delete_chain(m0, NULL); 2645 m0->m_flags &= ~M_PKTHDR; 2646 m->m_next = m0; 2647 m->m_pkthdr.len = m->m_len + m0->m_len; 2648 m0 = NULL; 2649 } 2650 noredhdropt:; 2651 if (m0) { 2652 m_freem(m0); 2653 m0 = NULL; 2654 } 2655 2656 /* XXX: clear embedded link IDs in the inner header */ 2657 in6_clearscope(&sip6->ip6_src); 2658 in6_clearscope(&sip6->ip6_dst); 2659 in6_clearscope(&nd_rd->nd_rd_target); 2660 in6_clearscope(&nd_rd->nd_rd_dst); 2661 2662 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr)); 2663 2664 nd_rd->nd_rd_cksum = 0; 2665 nd_rd->nd_rd_cksum = in6_cksum(m, IPPROTO_ICMPV6, 2666 sizeof(*ip6), ntohs(ip6->ip6_plen)); 2667 2668 /* send the packet to outside... */ 2669 ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL); 2670 if (outif) { 2671 icmp6_ifstat_inc(outif, ifs6_out_msg); 2672 icmp6_ifstat_inc(outif, ifs6_out_redirect); 2673 } 2674 icmp6stat.icp6s_outhist[ND_REDIRECT]++; 2675 2676 return; 2677 2678 fail: 2679 if (m) 2680 m_freem(m); 2681 if (m0) 2682 m_freem(m0); 2683 } 2684 2685 /* 2686 * ICMPv6 socket option processing. 2687 */ 2688 int 2689 icmp6_ctloutput(so, sopt) 2690 struct socket *so; 2691 struct sockopt *sopt; 2692 { 2693 int error = 0; 2694 int optlen; 2695 struct inpcb *inp = sotoinpcb(so); 2696 int level, op, optname; 2697 2698 if (sopt) { 2699 level = sopt->sopt_level; 2700 op = sopt->sopt_dir; 2701 optname = sopt->sopt_name; 2702 optlen = sopt->sopt_valsize; 2703 } else 2704 level = op = optname = optlen = 0; 2705 2706 if (level != IPPROTO_ICMPV6) { 2707 return EINVAL; 2708 } 2709 2710 switch (op) { 2711 case PRCO_SETOPT: 2712 switch (optname) { 2713 case ICMP6_FILTER: 2714 { 2715 struct icmp6_filter *p; 2716 2717 if (optlen != sizeof(*p)) { 2718 error = EMSGSIZE; 2719 break; 2720 } 2721 if (inp->in6p_icmp6filt == NULL) { 2722 error = EINVAL; 2723 break; 2724 } 2725 error = sooptcopyin(sopt, inp->in6p_icmp6filt, optlen, 2726 optlen); 2727 break; 2728 } 2729 2730 default: 2731 error = ENOPROTOOPT; 2732 break; 2733 } 2734 break; 2735 2736 case PRCO_GETOPT: 2737 switch (optname) { 2738 case ICMP6_FILTER: 2739 { 2740 if (inp->in6p_icmp6filt == NULL) { 2741 error = EINVAL; 2742 break; 2743 } 2744 error = sooptcopyout(sopt, inp->in6p_icmp6filt, 2745 sizeof(struct icmp6_filter)); 2746 break; 2747 } 2748 2749 default: 2750 error = ENOPROTOOPT; 2751 break; 2752 } 2753 break; 2754 } 2755 2756 return (error); 2757 } 2758 2759 /* 2760 * Perform rate limit check. 2761 * Returns 0 if it is okay to send the icmp6 packet. 2762 * Returns 1 if the router SHOULD NOT send this icmp6 packet due to rate 2763 * limitation. 2764 * 2765 * XXX per-destination/type check necessary? 2766 */ 2767 static int 2768 icmp6_ratelimit(dst, type, code) 2769 const struct in6_addr *dst; /* not used at this moment */ 2770 const int type; /* not used at this moment */ 2771 const int code; /* not used at this moment */ 2772 { 2773 int ret; 2774 2775 ret = 0; /* okay to send */ 2776 2777 /* PPS limit */ 2778 if (!ppsratecheck(&icmp6errppslim_last, &icmp6errpps_count, 2779 icmp6errppslim)) { 2780 /* The packet is subject to rate limit */ 2781 ret++; 2782 } 2783 2784 return ret; 2785 } 2786