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/mld6_var.h> 99 #include <netinet6/nd6.h> 100 101 #ifdef IPSEC 102 #include <netinet6/ipsec.h> 103 #include <netkey/key.h> 104 #endif 105 106 #ifdef FAST_IPSEC 107 #include <netipsec/ipsec.h> 108 #include <netipsec/key.h> 109 #endif 110 111 #include <net/net_osdep.h> 112 113 extern struct domain inet6domain; 114 115 struct icmp6stat icmp6stat; 116 117 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 **, char *)); 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 #ifdef COMPAT_RFC1885 138 static struct route_in6 icmp6_reflect_rt; 139 #endif 140 141 142 void 143 icmp6_init() 144 { 145 mld6_init(); 146 } 147 148 static void 149 icmp6_errcount(stat, type, code) 150 struct icmp6errstat *stat; 151 int type, code; 152 { 153 switch (type) { 154 case ICMP6_DST_UNREACH: 155 switch (code) { 156 case ICMP6_DST_UNREACH_NOROUTE: 157 stat->icp6errs_dst_unreach_noroute++; 158 return; 159 case ICMP6_DST_UNREACH_ADMIN: 160 stat->icp6errs_dst_unreach_admin++; 161 return; 162 case ICMP6_DST_UNREACH_BEYONDSCOPE: 163 stat->icp6errs_dst_unreach_beyondscope++; 164 return; 165 case ICMP6_DST_UNREACH_ADDR: 166 stat->icp6errs_dst_unreach_addr++; 167 return; 168 case ICMP6_DST_UNREACH_NOPORT: 169 stat->icp6errs_dst_unreach_noport++; 170 return; 171 } 172 break; 173 case ICMP6_PACKET_TOO_BIG: 174 stat->icp6errs_packet_too_big++; 175 return; 176 case ICMP6_TIME_EXCEEDED: 177 switch (code) { 178 case ICMP6_TIME_EXCEED_TRANSIT: 179 stat->icp6errs_time_exceed_transit++; 180 return; 181 case ICMP6_TIME_EXCEED_REASSEMBLY: 182 stat->icp6errs_time_exceed_reassembly++; 183 return; 184 } 185 break; 186 case ICMP6_PARAM_PROB: 187 switch (code) { 188 case ICMP6_PARAMPROB_HEADER: 189 stat->icp6errs_paramprob_header++; 190 return; 191 case ICMP6_PARAMPROB_NEXTHEADER: 192 stat->icp6errs_paramprob_nextheader++; 193 return; 194 case ICMP6_PARAMPROB_OPTION: 195 stat->icp6errs_paramprob_option++; 196 return; 197 } 198 break; 199 case ND_REDIRECT: 200 stat->icp6errs_redirect++; 201 return; 202 } 203 stat->icp6errs_unknown++; 204 } 205 206 /* 207 * Generate an error packet of type error in response to bad IP6 packet. 208 */ 209 void 210 icmp6_error(m, type, code, param) 211 struct mbuf *m; 212 int type, code, param; 213 { 214 struct ip6_hdr *oip6, *nip6; 215 struct icmp6_hdr *icmp6; 216 u_int preplen; 217 int off; 218 int nxt; 219 220 icmp6stat.icp6s_error++; 221 222 /* count per-type-code statistics */ 223 icmp6_errcount(&icmp6stat.icp6s_outerrhist, type, code); 224 225 #ifdef M_DECRYPTED /*not openbsd*/ 226 if (m->m_flags & M_DECRYPTED) { 227 icmp6stat.icp6s_canterror++; 228 goto freeit; 229 } 230 #endif 231 232 #ifndef PULLDOWN_TEST 233 IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), ); 234 #else 235 if (m->m_len < sizeof(struct ip6_hdr)) { 236 m = m_pullup(m, sizeof(struct ip6_hdr)); 237 if (m == NULL) 238 return; 239 } 240 #endif 241 oip6 = mtod(m, struct ip6_hdr *); 242 243 /* 244 * If the destination address of the erroneous packet is a multicast 245 * address, or the packet was sent using link-layer multicast, 246 * we should basically suppress sending an error (RFC 2463, Section 247 * 2.4). 248 * We have two exceptions (the item e.2 in that section): 249 * - the Pakcet Too Big message can be sent for path MTU discovery. 250 * - the Parameter Problem Message that can be allowed an icmp6 error 251 * in the option type field. This check has been done in 252 * ip6_unknown_opt(), so we can just check the type and code. 253 */ 254 if ((m->m_flags & (M_BCAST|M_MCAST) || 255 IN6_IS_ADDR_MULTICAST(&oip6->ip6_dst)) && 256 (type != ICMP6_PACKET_TOO_BIG && 257 (type != ICMP6_PARAM_PROB || 258 code != ICMP6_PARAMPROB_OPTION))) 259 goto freeit; 260 261 /* 262 * RFC 2463, 2.4 (e.5): source address check. 263 * XXX: the case of anycast source? 264 */ 265 if (IN6_IS_ADDR_UNSPECIFIED(&oip6->ip6_src) || 266 IN6_IS_ADDR_MULTICAST(&oip6->ip6_src)) 267 goto freeit; 268 269 /* 270 * If we are about to send ICMPv6 against ICMPv6 error/redirect, 271 * don't do it. 272 */ 273 nxt = -1; 274 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); 275 if (off >= 0 && nxt == IPPROTO_ICMPV6) { 276 struct icmp6_hdr *icp; 277 278 #ifndef PULLDOWN_TEST 279 IP6_EXTHDR_CHECK(m, 0, off + sizeof(struct icmp6_hdr), ); 280 icp = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 281 #else 282 IP6_EXTHDR_GET(icp, struct icmp6_hdr *, m, off, 283 sizeof(*icp)); 284 if (icp == NULL) { 285 icmp6stat.icp6s_tooshort++; 286 return; 287 } 288 #endif 289 if (icp->icmp6_type < ICMP6_ECHO_REQUEST || 290 icp->icmp6_type == ND_REDIRECT) { 291 /* 292 * ICMPv6 error 293 * Special case: for redirect (which is 294 * informational) we must not send icmp6 error. 295 */ 296 icmp6stat.icp6s_canterror++; 297 goto freeit; 298 } else { 299 /* ICMPv6 informational - send the error */ 300 } 301 } else { 302 /* non-ICMPv6 - send the error */ 303 } 304 305 oip6 = mtod(m, struct ip6_hdr *); /* adjust pointer */ 306 307 /* Finally, do rate limitation check. */ 308 if (icmp6_ratelimit(&oip6->ip6_src, type, code)) { 309 icmp6stat.icp6s_toofreq++; 310 goto freeit; 311 } 312 313 /* 314 * OK, ICMP6 can be generated. 315 */ 316 317 if (m->m_pkthdr.len >= ICMPV6_PLD_MAXLEN) 318 m_adj(m, ICMPV6_PLD_MAXLEN - m->m_pkthdr.len); 319 320 preplen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 321 M_PREPEND(m, preplen, M_DONTWAIT); 322 if (m && m->m_len < preplen) 323 m = m_pullup(m, preplen); 324 if (m == NULL) { 325 nd6log((LOG_DEBUG, "ENOBUFS in icmp6_error %d\n", __LINE__)); 326 return; 327 } 328 329 nip6 = mtod(m, struct ip6_hdr *); 330 nip6->ip6_src = oip6->ip6_src; 331 nip6->ip6_dst = oip6->ip6_dst; 332 333 in6_clearscope(&oip6->ip6_src); 334 in6_clearscope(&oip6->ip6_dst); 335 336 icmp6 = (struct icmp6_hdr *)(nip6 + 1); 337 icmp6->icmp6_type = type; 338 icmp6->icmp6_code = code; 339 icmp6->icmp6_pptr = htonl((u_int32_t)param); 340 341 /* 342 * icmp6_reflect() is designed to be in the input path. 343 * icmp6_error() can be called from both input and outut path, 344 * and if we are in output path rcvif could contain bogus value. 345 * clear m->m_pkthdr.rcvif for safety, we should have enough scope 346 * information in ip header (nip6). 347 */ 348 m->m_pkthdr.rcvif = NULL; 349 350 icmp6stat.icp6s_outhist[type]++; 351 icmp6_reflect(m, sizeof(struct ip6_hdr)); /* header order: IPv6 - ICMPv6 */ 352 353 return; 354 355 freeit: 356 /* 357 * If we can't tell wheter or not we can generate ICMP6, free it. 358 */ 359 m_freem(m); 360 } 361 362 /* 363 * Process a received ICMP6 message. 364 */ 365 int 366 icmp6_input(mp, offp, proto) 367 struct mbuf **mp; 368 int *offp, proto; 369 { 370 struct mbuf *m = *mp, *n; 371 struct ip6_hdr *ip6, *nip6; 372 struct icmp6_hdr *icmp6, *nicmp6; 373 int off = *offp; 374 int icmp6len = m->m_pkthdr.len - *offp; 375 int code, sum, noff; 376 377 #ifndef PULLDOWN_TEST 378 IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_hdr), IPPROTO_DONE); 379 /* m might change if M_LOOP. So, call mtod after this */ 380 #endif 381 382 /* 383 * Locate icmp6 structure in mbuf, and check 384 * that not corrupted and of at least minimum length 385 */ 386 387 ip6 = mtod(m, struct ip6_hdr *); 388 if (icmp6len < sizeof(struct icmp6_hdr)) { 389 icmp6stat.icp6s_tooshort++; 390 goto freeit; 391 } 392 393 /* 394 * calculate the checksum 395 */ 396 #ifndef PULLDOWN_TEST 397 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off); 398 #else 399 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 400 if (icmp6 == NULL) { 401 icmp6stat.icp6s_tooshort++; 402 return IPPROTO_DONE; 403 } 404 #endif 405 code = icmp6->icmp6_code; 406 407 if ((sum = in6_cksum(m, IPPROTO_ICMPV6, off, icmp6len)) != 0) { 408 nd6log((LOG_ERR, 409 "ICMP6 checksum error(%d|%x) %s\n", 410 icmp6->icmp6_type, sum, ip6_sprintf(&ip6->ip6_src))); 411 icmp6stat.icp6s_checksum++; 412 goto freeit; 413 } 414 415 if (faithprefix_p != NULL && (*faithprefix_p)(&ip6->ip6_dst)) { 416 /* 417 * Deliver very specific ICMP6 type only. 418 * This is important to deilver TOOBIG. Otherwise PMTUD 419 * will not work. 420 */ 421 switch (icmp6->icmp6_type) { 422 case ICMP6_DST_UNREACH: 423 case ICMP6_PACKET_TOO_BIG: 424 case ICMP6_TIME_EXCEEDED: 425 break; 426 default: 427 goto freeit; 428 } 429 } 430 431 icmp6stat.icp6s_inhist[icmp6->icmp6_type]++; 432 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_msg); 433 if (icmp6->icmp6_type < ICMP6_INFOMSG_MASK) 434 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_error); 435 436 switch (icmp6->icmp6_type) { 437 case ICMP6_DST_UNREACH: 438 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_dstunreach); 439 switch (code) { 440 case ICMP6_DST_UNREACH_NOROUTE: 441 code = PRC_UNREACH_NET; 442 break; 443 case ICMP6_DST_UNREACH_ADMIN: 444 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_adminprohib); 445 code = PRC_UNREACH_PROTOCOL; /* is this a good code? */ 446 break; 447 case ICMP6_DST_UNREACH_ADDR: 448 code = PRC_HOSTDEAD; 449 break; 450 #ifdef COMPAT_RFC1885 451 case ICMP6_DST_UNREACH_NOTNEIGHBOR: 452 code = PRC_UNREACH_SRCFAIL; 453 break; 454 #else 455 case ICMP6_DST_UNREACH_BEYONDSCOPE: 456 /* I mean "source address was incorrect." */ 457 code = PRC_PARAMPROB; 458 break; 459 #endif 460 case ICMP6_DST_UNREACH_NOPORT: 461 code = PRC_UNREACH_PORT; 462 break; 463 default: 464 goto badcode; 465 } 466 goto deliver; 467 break; 468 469 case ICMP6_PACKET_TOO_BIG: 470 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_pkttoobig); 471 if (code != 0) 472 goto badcode; 473 474 /* validation is made in icmp6_mtudisc_update */ 475 476 code = PRC_MSGSIZE; 477 478 /* 479 * Updating the path MTU will be done after examining 480 * intermediate extension headers. 481 */ 482 goto deliver; 483 break; 484 485 case ICMP6_TIME_EXCEEDED: 486 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_timeexceed); 487 switch (code) { 488 case ICMP6_TIME_EXCEED_TRANSIT: 489 case ICMP6_TIME_EXCEED_REASSEMBLY: 490 code += PRC_TIMXCEED_INTRANS; 491 break; 492 default: 493 goto badcode; 494 } 495 goto deliver; 496 break; 497 498 case ICMP6_PARAM_PROB: 499 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_paramprob); 500 switch (code) { 501 case ICMP6_PARAMPROB_NEXTHEADER: 502 code = PRC_UNREACH_PROTOCOL; 503 break; 504 case ICMP6_PARAMPROB_HEADER: 505 case ICMP6_PARAMPROB_OPTION: 506 code = PRC_PARAMPROB; 507 break; 508 default: 509 goto badcode; 510 } 511 goto deliver; 512 break; 513 514 case ICMP6_ECHO_REQUEST: 515 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echo); 516 if (code != 0) 517 goto badcode; 518 if ((n = m_copy(m, 0, M_COPYALL)) == NULL) { 519 /* Give up remote */ 520 break; 521 } 522 if ((n->m_flags & M_EXT) != 0 523 || n->m_len < off + sizeof(struct icmp6_hdr)) { 524 struct mbuf *n0 = n; 525 const int maxlen = sizeof(*nip6) + sizeof(*nicmp6); 526 int n0len; 527 528 /* 529 * Prepare an internal mbuf. m_pullup() doesn't 530 * always copy the length we specified. 531 */ 532 if (maxlen >= MCLBYTES) { 533 /* Give up remote */ 534 m_freem(n0); 535 break; 536 } 537 MGETHDR(n, M_DONTWAIT, n0->m_type); 538 n0len = n0->m_pkthdr.len; /* save for use below */ 539 if (n) 540 M_MOVE_PKTHDR(n, n0); 541 if (n && maxlen >= MHLEN) { 542 MCLGET(n, M_DONTWAIT); 543 if ((n->m_flags & M_EXT) == 0) { 544 m_free(n); 545 n = NULL; 546 } 547 } 548 if (n == NULL) { 549 /* Give up remote */ 550 m_freem(n0); 551 break; 552 } 553 /* 554 * Copy IPv6 and ICMPv6 only. 555 */ 556 nip6 = mtod(n, struct ip6_hdr *); 557 bcopy(ip6, nip6, sizeof(struct ip6_hdr)); 558 nicmp6 = (struct icmp6_hdr *)(nip6 + 1); 559 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr)); 560 noff = sizeof(struct ip6_hdr); 561 /* new mbuf contains only ipv6+icmpv6 headers */ 562 n->m_len = noff + sizeof(struct icmp6_hdr); 563 /* 564 * Adjust mbuf. ip6_plen will be adjusted in 565 * ip6_output(). 566 */ 567 m_adj(n0, off + sizeof(struct icmp6_hdr)); 568 /* recalculate complete packet size */ 569 n->m_pkthdr.len = n0len + (noff - off); 570 n->m_next = n0; 571 } else { 572 nip6 = mtod(n, struct ip6_hdr *); 573 nicmp6 = (struct icmp6_hdr *)((caddr_t)nip6 + off); 574 noff = off; 575 } 576 nicmp6->icmp6_type = ICMP6_ECHO_REPLY; 577 nicmp6->icmp6_code = 0; 578 if (n) { 579 icmp6stat.icp6s_reflect++; 580 icmp6stat.icp6s_outhist[ICMP6_ECHO_REPLY]++; 581 icmp6_reflect(n, noff); 582 } 583 break; 584 585 case ICMP6_ECHO_REPLY: 586 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echoreply); 587 if (code != 0) 588 goto badcode; 589 break; 590 591 case MLD_LISTENER_QUERY: 592 case MLD_LISTENER_REPORT: 593 if (icmp6len < sizeof(struct mld_hdr)) 594 goto badlen; 595 if (icmp6->icmp6_type == MLD_LISTENER_QUERY) /* XXX: ugly... */ 596 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldquery); 597 else 598 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldreport); 599 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 600 /* give up local */ 601 mld6_input(m, off); 602 m = NULL; 603 goto freeit; 604 } 605 mld6_input(n, off); 606 /* m stays. */ 607 break; 608 609 case MLD_LISTENER_DONE: 610 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mlddone); 611 if (icmp6len < sizeof(struct mld_hdr)) /* necessary? */ 612 goto badlen; 613 break; /* nothing to be done in kernel */ 614 615 case MLD_MTRACE_RESP: 616 case MLD_MTRACE: 617 /* XXX: these two are experimental. not officially defined. */ 618 /* XXX: per-interface statistics? */ 619 break; /* just pass it to applications */ 620 621 case ICMP6_WRUREQUEST: /* ICMP6_FQDN_QUERY */ 622 { 623 enum { WRU, FQDN } mode; 624 625 if (!icmp6_nodeinfo) 626 break; 627 628 if (icmp6len == sizeof(struct icmp6_hdr) + 4) 629 mode = WRU; 630 else if (icmp6len >= sizeof(struct icmp6_nodeinfo)) 631 mode = FQDN; 632 else 633 goto badlen; 634 635 #define hostnamelen strlen(hostname) 636 if (mode == FQDN) { 637 #ifndef PULLDOWN_TEST 638 IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_nodeinfo), 639 IPPROTO_DONE); 640 #endif 641 n = m_copy(m, 0, M_COPYALL); 642 if (n) 643 n = ni6_input(n, off); 644 /* XXX meaningless if n == NULL */ 645 noff = sizeof(struct ip6_hdr); 646 } else { 647 u_char *p; 648 int maxlen, maxhlen; 649 650 if ((icmp6_nodeinfo & 5) != 5) 651 break; 652 653 if (code != 0) 654 goto badcode; 655 maxlen = sizeof(*nip6) + sizeof(*nicmp6) + 4; 656 if (maxlen >= MCLBYTES) { 657 /* Give up remote */ 658 break; 659 } 660 MGETHDR(n, M_DONTWAIT, m->m_type); 661 if (n && maxlen > MHLEN) { 662 MCLGET(n, M_DONTWAIT); 663 if ((n->m_flags & M_EXT) == 0) { 664 m_free(n); 665 n = NULL; 666 } 667 } 668 if (!m_dup_pkthdr(n, m, M_DONTWAIT)) { 669 /* 670 * Previous code did a blind M_COPY_PKTHDR 671 * and said "just for rcvif". If true, then 672 * we could tolerate the dup failing (due to 673 * the deep copy of the tag chain). For now 674 * be conservative and just fail. 675 */ 676 m_free(n); 677 n = NULL; 678 } 679 if (n == NULL) { 680 /* Give up remote */ 681 break; 682 } 683 n->m_pkthdr.rcvif = NULL; 684 n->m_len = 0; 685 maxhlen = M_TRAILINGSPACE(n) - maxlen; 686 if (maxhlen > hostnamelen) 687 maxhlen = hostnamelen; 688 /* 689 * Copy IPv6 and ICMPv6 only. 690 */ 691 nip6 = mtod(n, struct ip6_hdr *); 692 bcopy(ip6, nip6, sizeof(struct ip6_hdr)); 693 nicmp6 = (struct icmp6_hdr *)(nip6 + 1); 694 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr)); 695 p = (u_char *)(nicmp6 + 1); 696 bzero(p, 4); 697 bcopy(hostname, p + 4, maxhlen); /* meaningless TTL */ 698 noff = sizeof(struct ip6_hdr); 699 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) + 700 sizeof(struct icmp6_hdr) + 4 + maxhlen; 701 nicmp6->icmp6_type = ICMP6_WRUREPLY; 702 nicmp6->icmp6_code = 0; 703 } 704 #undef hostnamelen 705 if (n) { 706 icmp6stat.icp6s_reflect++; 707 icmp6stat.icp6s_outhist[ICMP6_WRUREPLY]++; 708 icmp6_reflect(n, noff); 709 } 710 break; 711 } 712 713 case ICMP6_WRUREPLY: 714 if (code != 0) 715 goto badcode; 716 break; 717 718 case ND_ROUTER_SOLICIT: 719 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routersolicit); 720 if (code != 0) 721 goto badcode; 722 if (icmp6len < sizeof(struct nd_router_solicit)) 723 goto badlen; 724 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 725 /* give up local */ 726 nd6_rs_input(m, off, icmp6len); 727 m = NULL; 728 goto freeit; 729 } 730 nd6_rs_input(n, off, icmp6len); 731 /* m stays. */ 732 break; 733 734 case ND_ROUTER_ADVERT: 735 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routeradvert); 736 if (code != 0) 737 goto badcode; 738 if (icmp6len < sizeof(struct nd_router_advert)) 739 goto badlen; 740 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 741 /* give up local */ 742 nd6_ra_input(m, off, icmp6len); 743 m = NULL; 744 goto freeit; 745 } 746 nd6_ra_input(n, off, icmp6len); 747 /* m stays. */ 748 break; 749 750 case ND_NEIGHBOR_SOLICIT: 751 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighborsolicit); 752 if (code != 0) 753 goto badcode; 754 if (icmp6len < sizeof(struct nd_neighbor_solicit)) 755 goto badlen; 756 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 757 /* give up local */ 758 nd6_ns_input(m, off, icmp6len); 759 m = NULL; 760 goto freeit; 761 } 762 nd6_ns_input(n, off, icmp6len); 763 /* m stays. */ 764 break; 765 766 case ND_NEIGHBOR_ADVERT: 767 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighboradvert); 768 if (code != 0) 769 goto badcode; 770 if (icmp6len < sizeof(struct nd_neighbor_advert)) 771 goto badlen; 772 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 773 /* give up local */ 774 nd6_na_input(m, off, icmp6len); 775 m = NULL; 776 goto freeit; 777 } 778 nd6_na_input(n, off, icmp6len); 779 /* m stays. */ 780 break; 781 782 case ND_REDIRECT: 783 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_redirect); 784 if (code != 0) 785 goto badcode; 786 if (icmp6len < sizeof(struct nd_redirect)) 787 goto badlen; 788 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 789 /* give up local */ 790 icmp6_redirect_input(m, off); 791 m = NULL; 792 goto freeit; 793 } 794 icmp6_redirect_input(n, off); 795 /* m stays. */ 796 break; 797 798 case ICMP6_ROUTER_RENUMBERING: 799 if (code != ICMP6_ROUTER_RENUMBERING_COMMAND && 800 code != ICMP6_ROUTER_RENUMBERING_RESULT) 801 goto badcode; 802 if (icmp6len < sizeof(struct icmp6_router_renum)) 803 goto badlen; 804 break; 805 806 default: 807 nd6log((LOG_DEBUG, 808 "icmp6_input: unknown type %d(src=%s, dst=%s, ifid=%d)\n", 809 icmp6->icmp6_type, ip6_sprintf(&ip6->ip6_src), 810 ip6_sprintf(&ip6->ip6_dst), 811 m->m_pkthdr.rcvif ? m->m_pkthdr.rcvif->if_index : 0)); 812 if (icmp6->icmp6_type < ICMP6_ECHO_REQUEST) { 813 /* ICMPv6 error: MUST deliver it by spec... */ 814 code = PRC_NCMDS; 815 /* deliver */ 816 } else { 817 /* ICMPv6 informational: MUST not deliver */ 818 break; 819 } 820 deliver: 821 if (icmp6_notify_error(m, off, icmp6len, code)) { 822 /* In this case, m should've been freed. */ 823 return (IPPROTO_DONE); 824 } 825 break; 826 827 badcode: 828 icmp6stat.icp6s_badcode++; 829 break; 830 831 badlen: 832 icmp6stat.icp6s_badlen++; 833 break; 834 } 835 836 /* deliver the packet to appropriate sockets */ 837 icmp6_rip6_input(&m, *offp); 838 839 return IPPROTO_DONE; 840 841 freeit: 842 m_freem(m); 843 return IPPROTO_DONE; 844 } 845 846 static int 847 icmp6_notify_error(m, off, icmp6len, code) 848 struct mbuf *m; 849 int off, icmp6len, code; 850 { 851 struct icmp6_hdr *icmp6; 852 struct ip6_hdr *eip6; 853 u_int32_t notifymtu; 854 struct sockaddr_in6 icmp6src, icmp6dst; 855 856 if (icmp6len < sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr)) { 857 icmp6stat.icp6s_tooshort++; 858 goto freeit; 859 } 860 #ifndef PULLDOWN_TEST 861 IP6_EXTHDR_CHECK(m, off, 862 sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr), -1); 863 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 864 #else 865 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, 866 sizeof(*icmp6) + sizeof(struct ip6_hdr)); 867 if (icmp6 == NULL) { 868 icmp6stat.icp6s_tooshort++; 869 return (-1); 870 } 871 #endif 872 eip6 = (struct ip6_hdr *)(icmp6 + 1); 873 874 /* Detect the upper level protocol */ 875 { 876 void (*ctlfunc) __P((int, struct sockaddr *, void *)); 877 u_int8_t nxt = eip6->ip6_nxt; 878 int eoff = off + sizeof(struct icmp6_hdr) + 879 sizeof(struct ip6_hdr); 880 struct ip6ctlparam ip6cp; 881 struct in6_addr *finaldst = NULL; 882 int icmp6type = icmp6->icmp6_type; 883 struct ip6_frag *fh; 884 struct ip6_rthdr *rth; 885 struct ip6_rthdr0 *rth0; 886 int rthlen; 887 888 while (1) { /* XXX: should avoid infinite loop explicitly? */ 889 struct ip6_ext *eh; 890 891 switch (nxt) { 892 case IPPROTO_HOPOPTS: 893 case IPPROTO_DSTOPTS: 894 case IPPROTO_AH: 895 #ifndef PULLDOWN_TEST 896 IP6_EXTHDR_CHECK(m, 0, 897 eoff + sizeof(struct ip6_ext), -1); 898 eh = (struct ip6_ext *)(mtod(m, caddr_t) + eoff); 899 #else 900 IP6_EXTHDR_GET(eh, struct ip6_ext *, m, 901 eoff, sizeof(*eh)); 902 if (eh == NULL) { 903 icmp6stat.icp6s_tooshort++; 904 return (-1); 905 } 906 #endif 907 908 if (nxt == IPPROTO_AH) 909 eoff += (eh->ip6e_len + 2) << 2; 910 else 911 eoff += (eh->ip6e_len + 1) << 3; 912 nxt = eh->ip6e_nxt; 913 break; 914 case IPPROTO_ROUTING: 915 /* 916 * When the erroneous packet contains a 917 * routing header, we should examine the 918 * header to determine the final destination. 919 * Otherwise, we can't properly update 920 * information that depends on the final 921 * destination (e.g. path MTU). 922 */ 923 #ifndef PULLDOWN_TEST 924 IP6_EXTHDR_CHECK(m, 0, eoff + sizeof(*rth), -1); 925 rth = (struct ip6_rthdr *) 926 (mtod(m, caddr_t) + eoff); 927 #else 928 IP6_EXTHDR_GET(rth, struct ip6_rthdr *, m, 929 eoff, sizeof(*rth)); 930 if (rth == NULL) { 931 icmp6stat.icp6s_tooshort++; 932 return (-1); 933 } 934 #endif 935 rthlen = (rth->ip6r_len + 1) << 3; 936 /* 937 * XXX: currently there is no 938 * officially defined type other 939 * than type-0. 940 * Note that if the segment left field 941 * is 0, all intermediate hops must 942 * have been passed. 943 */ 944 if (rth->ip6r_segleft && 945 rth->ip6r_type == IPV6_RTHDR_TYPE_0) { 946 int hops; 947 948 #ifndef PULLDOWN_TEST 949 IP6_EXTHDR_CHECK(m, 0, eoff + rthlen, -1); 950 rth0 = (struct ip6_rthdr0 *) 951 (mtod(m, caddr_t) + eoff); 952 #else 953 IP6_EXTHDR_GET(rth0, 954 struct ip6_rthdr0 *, m, 955 eoff, rthlen); 956 if (rth0 == NULL) { 957 icmp6stat.icp6s_tooshort++; 958 return (-1); 959 } 960 #endif 961 /* just ignore a bogus header */ 962 if ((rth0->ip6r0_len % 2) == 0 && 963 (hops = rth0->ip6r0_len/2)) 964 finaldst = (struct in6_addr *)(rth0 + 1) + (hops - 1); 965 } 966 eoff += rthlen; 967 nxt = rth->ip6r_nxt; 968 break; 969 case IPPROTO_FRAGMENT: 970 #ifndef PULLDOWN_TEST 971 IP6_EXTHDR_CHECK(m, 0, eoff + 972 sizeof(struct ip6_frag), -1); 973 fh = (struct ip6_frag *)(mtod(m, caddr_t) + 974 eoff); 975 #else 976 IP6_EXTHDR_GET(fh, struct ip6_frag *, m, 977 eoff, sizeof(*fh)); 978 if (fh == NULL) { 979 icmp6stat.icp6s_tooshort++; 980 return (-1); 981 } 982 #endif 983 /* 984 * Data after a fragment header is meaningless 985 * unless it is the first fragment, but 986 * we'll go to the notify label for path MTU 987 * discovery. 988 */ 989 if (fh->ip6f_offlg & IP6F_OFF_MASK) 990 goto notify; 991 992 eoff += sizeof(struct ip6_frag); 993 nxt = fh->ip6f_nxt; 994 break; 995 default: 996 /* 997 * This case includes ESP and the No Next 998 * Header. In such cases going to the notify 999 * label does not have any meaning 1000 * (i.e. ctlfunc will be NULL), but we go 1001 * anyway since we might have to update 1002 * path MTU information. 1003 */ 1004 goto notify; 1005 } 1006 } 1007 notify: 1008 #ifndef PULLDOWN_TEST 1009 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 1010 #else 1011 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, 1012 sizeof(*icmp6) + sizeof(struct ip6_hdr)); 1013 if (icmp6 == NULL) { 1014 icmp6stat.icp6s_tooshort++; 1015 return (-1); 1016 } 1017 #endif 1018 1019 /* 1020 * retrieve parameters from the inner IPv6 header, and convert 1021 * them into sockaddr structures. 1022 * XXX: there is no guarantee that the source or destination 1023 * addresses of the inner packet are in the same scope as 1024 * the addresses of the icmp packet. But there is no other 1025 * way to determine the zone. 1026 */ 1027 eip6 = (struct ip6_hdr *)(icmp6 + 1); 1028 1029 bzero(&icmp6dst, sizeof(icmp6dst)); 1030 icmp6dst.sin6_len = sizeof(struct sockaddr_in6); 1031 icmp6dst.sin6_family = AF_INET6; 1032 if (finaldst == NULL) 1033 icmp6dst.sin6_addr = eip6->ip6_dst; 1034 else 1035 icmp6dst.sin6_addr = *finaldst; 1036 if (in6_addr2zoneid(m->m_pkthdr.rcvif, &icmp6dst.sin6_addr, 1037 &icmp6dst.sin6_scope_id)) 1038 goto freeit; 1039 if (in6_embedscope(&icmp6dst.sin6_addr, &icmp6dst, 1040 NULL, NULL)) { 1041 /* should be impossbile */ 1042 nd6log((LOG_DEBUG, 1043 "icmp6_notify_error: in6_embedscope failed\n")); 1044 goto freeit; 1045 } 1046 1047 /* 1048 * retrieve parameters from the inner IPv6 header, and convert 1049 * them into sockaddr structures. 1050 */ 1051 bzero(&icmp6src, sizeof(icmp6src)); 1052 icmp6src.sin6_len = sizeof(struct sockaddr_in6); 1053 icmp6src.sin6_family = AF_INET6; 1054 icmp6src.sin6_addr = eip6->ip6_src; 1055 if (in6_addr2zoneid(m->m_pkthdr.rcvif, &icmp6src.sin6_addr, 1056 &icmp6src.sin6_scope_id)) { 1057 goto freeit; 1058 } 1059 if (in6_embedscope(&icmp6src.sin6_addr, &icmp6src, 1060 NULL, NULL)) { 1061 /* should be impossbile */ 1062 nd6log((LOG_DEBUG, 1063 "icmp6_notify_error: in6_embedscope failed\n")); 1064 goto freeit; 1065 } 1066 icmp6src.sin6_flowinfo = (eip6->ip6_flow & IPV6_FLOWLABEL_MASK); 1067 1068 if (finaldst == NULL) 1069 finaldst = &eip6->ip6_dst; 1070 ip6cp.ip6c_m = m; 1071 ip6cp.ip6c_icmp6 = icmp6; 1072 ip6cp.ip6c_ip6 = (struct ip6_hdr *)(icmp6 + 1); 1073 ip6cp.ip6c_off = eoff; 1074 ip6cp.ip6c_finaldst = finaldst; 1075 ip6cp.ip6c_src = &icmp6src; 1076 ip6cp.ip6c_nxt = nxt; 1077 1078 if (icmp6type == ICMP6_PACKET_TOO_BIG) { 1079 notifymtu = ntohl(icmp6->icmp6_mtu); 1080 ip6cp.ip6c_cmdarg = (void *)¬ifymtu; 1081 icmp6_mtudisc_update(&ip6cp, 1); /*XXX*/ 1082 } 1083 1084 ctlfunc = (void (*) __P((int, struct sockaddr *, void *))) 1085 (inet6sw[ip6_protox[nxt]].pr_ctlinput); 1086 if (ctlfunc) { 1087 (void) (*ctlfunc)(code, (struct sockaddr *)&icmp6dst, 1088 &ip6cp); 1089 } 1090 } 1091 return (0); 1092 1093 freeit: 1094 m_freem(m); 1095 return (-1); 1096 } 1097 1098 void 1099 icmp6_mtudisc_update(ip6cp, validated) 1100 struct ip6ctlparam *ip6cp; 1101 int validated; 1102 { 1103 struct in6_addr *dst = ip6cp->ip6c_finaldst; 1104 struct icmp6_hdr *icmp6 = ip6cp->ip6c_icmp6; 1105 struct mbuf *m = ip6cp->ip6c_m; /* will be necessary for scope issue */ 1106 u_int mtu = ntohl(icmp6->icmp6_mtu); 1107 struct in_conninfo inc; 1108 1109 #if 0 1110 /* 1111 * RFC2460 section 5, last paragraph. 1112 * even though minimum link MTU for IPv6 is IPV6_MMTU, 1113 * we may see ICMPv6 too big with mtu < IPV6_MMTU 1114 * due to packet translator in the middle. 1115 * see ip6_output() and ip6_getpmtu() "alwaysfrag" case for 1116 * special handling. 1117 */ 1118 if (mtu < IPV6_MMTU) 1119 return; 1120 #endif 1121 1122 /* 1123 * we reject ICMPv6 too big with abnormally small value. 1124 * XXX what is the good definition of "abnormally small"? 1125 */ 1126 if (mtu < sizeof(struct ip6_hdr) + sizeof(struct ip6_frag) + 8) 1127 return; 1128 1129 if (!validated) 1130 return; 1131 1132 bzero(&inc, sizeof(inc)); 1133 inc.inc_flags = 1; /* IPv6 */ 1134 inc.inc6_faddr = *dst; 1135 /* XXX normally, this won't happen */ 1136 if (IN6_IS_ADDR_LINKLOCAL(dst)) { 1137 inc.inc6_faddr.s6_addr16[1] = 1138 htons(m->m_pkthdr.rcvif->if_index); 1139 } 1140 1141 if (mtu < tcp_maxmtu6(&inc)) { 1142 tcp_hc_updatemtu(&inc, mtu); 1143 icmp6stat.icp6s_pmtuchg++; 1144 } 1145 } 1146 1147 /* 1148 * Process a Node Information Query packet, based on 1149 * draft-ietf-ipngwg-icmp-name-lookups-07. 1150 * 1151 * Spec incompatibilities: 1152 * - IPv6 Subject address handling 1153 * - IPv4 Subject address handling support missing 1154 * - Proxy reply (answer even if it's not for me) 1155 * - joins NI group address at in6_ifattach() time only, does not cope 1156 * with hostname changes by sethostname(3) 1157 */ 1158 #define hostnamelen strlen(hostname) 1159 static struct mbuf * 1160 ni6_input(m, off) 1161 struct mbuf *m; 1162 int off; 1163 { 1164 struct icmp6_nodeinfo *ni6, *nni6; 1165 struct mbuf *n = NULL; 1166 u_int16_t qtype; 1167 int subjlen; 1168 int replylen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo); 1169 struct ni_reply_fqdn *fqdn; 1170 int addrs; /* for NI_QTYPE_NODEADDR */ 1171 struct ifnet *ifp = NULL; /* for NI_QTYPE_NODEADDR */ 1172 struct sockaddr_in6 sin6_sbj; /* subject address */ 1173 struct sockaddr_in6 sin6_d; 1174 struct ip6_hdr *ip6; 1175 int oldfqdn = 0; /* if 1, return pascal string (03 draft) */ 1176 char *subj = NULL; 1177 struct in6_ifaddr *ia6 = NULL; 1178 1179 ip6 = mtod(m, struct ip6_hdr *); 1180 #ifndef PULLDOWN_TEST 1181 ni6 = (struct icmp6_nodeinfo *)(mtod(m, caddr_t) + off); 1182 #else 1183 IP6_EXTHDR_GET(ni6, struct icmp6_nodeinfo *, m, off, sizeof(*ni6)); 1184 if (ni6 == NULL) { 1185 /* m is already reclaimed */ 1186 return (NULL); 1187 } 1188 #endif 1189 1190 bzero(&sin6_d, sizeof(sin6_d)); 1191 sin6_d.sin6_family = AF_INET6; /* not used, actually */ 1192 sin6_d.sin6_len = sizeof(sin6_d); /* ditto */ 1193 sin6_d.sin6_addr = ip6->ip6_dst; 1194 if (in6_addr2zoneid(m->m_pkthdr.rcvif, &ip6->ip6_dst, 1195 &sin6_d.sin6_scope_id)) { 1196 goto bad; 1197 } 1198 if (in6_embedscope(&sin6_d.sin6_addr, &sin6_d, NULL, NULL)) 1199 goto bad; /* XXX should not happen */ 1200 1201 /* 1202 * Validate IPv6 destination address. 1203 * 1204 * The Responder must discard the Query without further processing 1205 * unless it is one of the Responder's unicast or anycast addresses, or 1206 * a link-local scope multicast address which the Responder has joined. 1207 * [icmp-name-lookups-08, Section 4.] 1208 */ 1209 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 1210 if (!IN6_IS_ADDR_MC_LINKLOCAL(&ip6->ip6_dst)) 1211 goto bad; 1212 /* else it's a link-local multicast, fine */ 1213 } else { /* unicast or anycast */ 1214 if ((ia6 = ip6_getdstifaddr(m)) == NULL) 1215 goto bad; /* XXX impossible */ 1216 1217 if ((ia6->ia6_flags & IN6_IFF_TEMPORARY) && 1218 !(icmp6_nodeinfo & 4)) { 1219 nd6log((LOG_DEBUG, "ni6_input: ignore node info to " 1220 "a temporary address in %s:%d", 1221 __FILE__, __LINE__)); 1222 goto bad; 1223 } 1224 } 1225 1226 /* validate query Subject field. */ 1227 qtype = ntohs(ni6->ni_qtype); 1228 subjlen = m->m_pkthdr.len - off - sizeof(struct icmp6_nodeinfo); 1229 switch (qtype) { 1230 case NI_QTYPE_NOOP: 1231 case NI_QTYPE_SUPTYPES: 1232 /* 07 draft */ 1233 if (ni6->ni_code == ICMP6_NI_SUBJ_FQDN && subjlen == 0) 1234 break; 1235 /* FALLTHROUGH */ 1236 case NI_QTYPE_FQDN: 1237 case NI_QTYPE_NODEADDR: 1238 switch (ni6->ni_code) { 1239 case ICMP6_NI_SUBJ_IPV6: 1240 #if ICMP6_NI_SUBJ_IPV6 != 0 1241 case 0: 1242 #endif 1243 /* 1244 * backward compatibility - try to accept 03 draft 1245 * format, where no Subject is present. 1246 */ 1247 if (qtype == NI_QTYPE_FQDN && ni6->ni_code == 0 && 1248 subjlen == 0) { 1249 oldfqdn++; 1250 break; 1251 } 1252 #if ICMP6_NI_SUBJ_IPV6 != 0 1253 if (ni6->ni_code != ICMP6_NI_SUBJ_IPV6) 1254 goto bad; 1255 #endif 1256 1257 if (subjlen != sizeof(struct in6_addr)) 1258 goto bad; 1259 1260 /* 1261 * Validate Subject address. 1262 * 1263 * Not sure what exactly "address belongs to the node" 1264 * means in the spec, is it just unicast, or what? 1265 * 1266 * At this moment we consider Subject address as 1267 * "belong to the node" if the Subject address equals 1268 * to the IPv6 destination address; validation for 1269 * IPv6 destination address should have done enough 1270 * check for us. 1271 * 1272 * We do not do proxy at this moment. 1273 */ 1274 /* m_pulldown instead of copy? */ 1275 bzero(&sin6_sbj, sizeof(sin6_sbj)); 1276 sin6_sbj.sin6_family = AF_INET6; 1277 sin6_sbj.sin6_len = sizeof(sin6_sbj); 1278 m_copydata(m, off + sizeof(struct icmp6_nodeinfo), 1279 subjlen, (caddr_t)&sin6_sbj.sin6_addr); 1280 if (in6_addr2zoneid(m->m_pkthdr.rcvif, 1281 &sin6_sbj.sin6_addr, &sin6_sbj.sin6_scope_id)) { 1282 goto bad; 1283 } 1284 if (in6_embedscope(&sin6_sbj.sin6_addr, &sin6_sbj, 1285 NULL, NULL)) 1286 goto bad; /* XXX should not happen */ 1287 1288 subj = (char *)&sin6_sbj; 1289 if (SA6_ARE_ADDR_EQUAL(&sin6_sbj, &sin6_d)) 1290 break; 1291 1292 /* 1293 * XXX if we are to allow other cases, we should really 1294 * be careful about scope here. 1295 * basically, we should disallow queries toward IPv6 1296 * destination X with subject Y, 1297 * if scope(X) > scope(Y). 1298 * if we allow scope(X) > scope(Y), it will result in 1299 * information leakage across scope boundary. 1300 */ 1301 goto bad; 1302 1303 case ICMP6_NI_SUBJ_FQDN: 1304 /* 1305 * Validate Subject name with gethostname(3). 1306 * 1307 * The behavior may need some debate, since: 1308 * - we are not sure if the node has FQDN as 1309 * hostname (returned by gethostname(3)). 1310 * - the code does wildcard match for truncated names. 1311 * however, we are not sure if we want to perform 1312 * wildcard match, if gethostname(3) side has 1313 * truncated hostname. 1314 */ 1315 n = ni6_nametodns(hostname, hostnamelen, 0); 1316 if (!n || n->m_next || n->m_len == 0) 1317 goto bad; 1318 IP6_EXTHDR_GET(subj, char *, m, 1319 off + sizeof(struct icmp6_nodeinfo), subjlen); 1320 if (subj == NULL) 1321 goto bad; 1322 if (!ni6_dnsmatch(subj, subjlen, mtod(n, const char *), 1323 n->m_len)) { 1324 goto bad; 1325 } 1326 m_freem(n); 1327 n = NULL; 1328 break; 1329 1330 case ICMP6_NI_SUBJ_IPV4: /* XXX: to be implemented? */ 1331 default: 1332 goto bad; 1333 } 1334 break; 1335 } 1336 1337 /* refuse based on configuration. XXX ICMP6_NI_REFUSED? */ 1338 switch (qtype) { 1339 case NI_QTYPE_FQDN: 1340 if ((icmp6_nodeinfo & 1) == 0) 1341 goto bad; 1342 break; 1343 case NI_QTYPE_NODEADDR: 1344 if ((icmp6_nodeinfo & 2) == 0) 1345 goto bad; 1346 break; 1347 } 1348 1349 /* guess reply length */ 1350 switch (qtype) { 1351 case NI_QTYPE_NOOP: 1352 break; /* no reply data */ 1353 case NI_QTYPE_SUPTYPES: 1354 replylen += sizeof(u_int32_t); 1355 break; 1356 case NI_QTYPE_FQDN: 1357 /* XXX will append an mbuf */ 1358 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1359 break; 1360 case NI_QTYPE_NODEADDR: 1361 addrs = ni6_addrs(ni6, m, &ifp, subj); 1362 if ((replylen += addrs * (sizeof(struct in6_addr) + 1363 sizeof(u_int32_t))) > MCLBYTES) 1364 replylen = MCLBYTES; /* XXX: will truncate pkt later */ 1365 break; 1366 default: 1367 /* 1368 * XXX: We must return a reply with the ICMP6 code 1369 * `unknown Qtype' in this case. However we regard the case 1370 * as an FQDN query for backward compatibility. 1371 * Older versions set a random value to this field, 1372 * so it rarely varies in the defined qtypes. 1373 * But the mechanism is not reliable... 1374 * maybe we should obsolete older versions. 1375 */ 1376 qtype = NI_QTYPE_FQDN; 1377 /* XXX will append an mbuf */ 1378 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1379 oldfqdn++; 1380 break; 1381 } 1382 1383 /* allocate an mbuf to reply. */ 1384 MGETHDR(n, M_DONTWAIT, m->m_type); 1385 if (n == NULL) { 1386 m_freem(m); 1387 return (NULL); 1388 } 1389 M_MOVE_PKTHDR(n, m); /* just for recvif */ 1390 if (replylen > MHLEN) { 1391 if (replylen > MCLBYTES) { 1392 /* 1393 * XXX: should we try to allocate more? But MCLBYTES 1394 * is probably much larger than IPV6_MMTU... 1395 */ 1396 goto bad; 1397 } 1398 MCLGET(n, M_DONTWAIT); 1399 if ((n->m_flags & M_EXT) == 0) { 1400 goto bad; 1401 } 1402 } 1403 n->m_pkthdr.len = n->m_len = replylen; 1404 1405 /* copy mbuf header and IPv6 + Node Information base headers */ 1406 bcopy(mtod(m, caddr_t), mtod(n, caddr_t), sizeof(struct ip6_hdr)); 1407 nni6 = (struct icmp6_nodeinfo *)(mtod(n, struct ip6_hdr *) + 1); 1408 bcopy((caddr_t)ni6, (caddr_t)nni6, sizeof(struct icmp6_nodeinfo)); 1409 1410 /* qtype dependent procedure */ 1411 switch (qtype) { 1412 case NI_QTYPE_NOOP: 1413 nni6->ni_code = ICMP6_NI_SUCCESS; 1414 nni6->ni_flags = 0; 1415 break; 1416 case NI_QTYPE_SUPTYPES: 1417 { 1418 u_int32_t v; 1419 nni6->ni_code = ICMP6_NI_SUCCESS; 1420 nni6->ni_flags = htons(0x0000); /* raw bitmap */ 1421 /* supports NOOP, SUPTYPES, FQDN, and NODEADDR */ 1422 v = (u_int32_t)htonl(0x0000000f); 1423 bcopy(&v, nni6 + 1, sizeof(u_int32_t)); 1424 break; 1425 } 1426 case NI_QTYPE_FQDN: 1427 nni6->ni_code = ICMP6_NI_SUCCESS; 1428 fqdn = (struct ni_reply_fqdn *)(mtod(n, caddr_t) + 1429 sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo)); 1430 nni6->ni_flags = 0; /* XXX: meaningless TTL */ 1431 fqdn->ni_fqdn_ttl = 0; /* ditto. */ 1432 /* 1433 * XXX do we really have FQDN in variable "hostname"? 1434 */ 1435 n->m_next = ni6_nametodns(hostname, hostnamelen, oldfqdn); 1436 if (n->m_next == NULL) 1437 goto bad; 1438 /* XXX we assume that n->m_next is not a chain */ 1439 if (n->m_next->m_next != NULL) 1440 goto bad; 1441 n->m_pkthdr.len += n->m_next->m_len; 1442 break; 1443 case NI_QTYPE_NODEADDR: 1444 { 1445 int lenlim, copied; 1446 1447 nni6->ni_code = ICMP6_NI_SUCCESS; 1448 n->m_pkthdr.len = n->m_len = 1449 sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo); 1450 lenlim = M_TRAILINGSPACE(n); 1451 copied = ni6_store_addrs(ni6, nni6, ifp, lenlim); 1452 /* XXX: reset mbuf length */ 1453 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) + 1454 sizeof(struct icmp6_nodeinfo) + copied; 1455 break; 1456 } 1457 default: 1458 break; /* XXX impossible! */ 1459 } 1460 1461 nni6->ni_type = ICMP6_NI_REPLY; 1462 m_freem(m); 1463 return (n); 1464 1465 bad: 1466 m_freem(m); 1467 if (n) 1468 m_freem(n); 1469 return (NULL); 1470 } 1471 #undef hostnamelen 1472 1473 /* 1474 * make a mbuf with DNS-encoded string. no compression support. 1475 * 1476 * XXX names with less than 2 dots (like "foo" or "foo.section") will be 1477 * treated as truncated name (two \0 at the end). this is a wild guess. 1478 */ 1479 static struct mbuf * 1480 ni6_nametodns(name, namelen, old) 1481 const char *name; 1482 int namelen; 1483 int old; /* return pascal string if non-zero */ 1484 { 1485 struct mbuf *m; 1486 char *cp, *ep; 1487 const char *p, *q; 1488 int i, len, nterm; 1489 1490 if (old) 1491 len = namelen + 1; 1492 else 1493 len = MCLBYTES; 1494 1495 /* because MAXHOSTNAMELEN is usually 256, we use cluster mbuf */ 1496 MGET(m, M_DONTWAIT, MT_DATA); 1497 if (m && len > MLEN) { 1498 MCLGET(m, M_DONTWAIT); 1499 if ((m->m_flags & M_EXT) == 0) 1500 goto fail; 1501 } 1502 if (!m) 1503 goto fail; 1504 m->m_next = NULL; 1505 1506 if (old) { 1507 m->m_len = len; 1508 *mtod(m, char *) = namelen; 1509 bcopy(name, mtod(m, char *) + 1, namelen); 1510 return m; 1511 } else { 1512 m->m_len = 0; 1513 cp = mtod(m, char *); 1514 ep = mtod(m, char *) + M_TRAILINGSPACE(m); 1515 1516 /* if not certain about my name, return empty buffer */ 1517 if (namelen == 0) 1518 return m; 1519 1520 /* 1521 * guess if it looks like shortened hostname, or FQDN. 1522 * shortened hostname needs two trailing "\0". 1523 */ 1524 i = 0; 1525 for (p = name; p < name + namelen; p++) { 1526 if (*p && *p == '.') 1527 i++; 1528 } 1529 if (i < 2) 1530 nterm = 2; 1531 else 1532 nterm = 1; 1533 1534 p = name; 1535 while (cp < ep && p < name + namelen) { 1536 i = 0; 1537 for (q = p; q < name + namelen && *q && *q != '.'; q++) 1538 i++; 1539 /* result does not fit into mbuf */ 1540 if (cp + i + 1 >= ep) 1541 goto fail; 1542 /* 1543 * DNS label length restriction, RFC1035 page 8. 1544 * "i == 0" case is included here to avoid returning 1545 * 0-length label on "foo..bar". 1546 */ 1547 if (i <= 0 || i >= 64) 1548 goto fail; 1549 *cp++ = i; 1550 bcopy(p, cp, i); 1551 cp += i; 1552 p = q; 1553 if (p < name + namelen && *p == '.') 1554 p++; 1555 } 1556 /* termination */ 1557 if (cp + nterm >= ep) 1558 goto fail; 1559 while (nterm-- > 0) 1560 *cp++ = '\0'; 1561 m->m_len = cp - mtod(m, char *); 1562 return m; 1563 } 1564 1565 panic("should not reach here"); 1566 /* NOTREACHED */ 1567 1568 fail: 1569 if (m) 1570 m_freem(m); 1571 return NULL; 1572 } 1573 1574 /* 1575 * check if two DNS-encoded string matches. takes care of truncated 1576 * form (with \0\0 at the end). no compression support. 1577 * XXX upper/lowercase match (see RFC2065) 1578 */ 1579 static int 1580 ni6_dnsmatch(a, alen, b, blen) 1581 const char *a; 1582 int alen; 1583 const char *b; 1584 int blen; 1585 { 1586 const char *a0, *b0; 1587 int l; 1588 1589 /* simplest case - need validation? */ 1590 if (alen == blen && bcmp(a, b, alen) == 0) 1591 return 1; 1592 1593 a0 = a; 1594 b0 = b; 1595 1596 /* termination is mandatory */ 1597 if (alen < 2 || blen < 2) 1598 return 0; 1599 if (a0[alen - 1] != '\0' || b0[blen - 1] != '\0') 1600 return 0; 1601 alen--; 1602 blen--; 1603 1604 while (a - a0 < alen && b - b0 < blen) { 1605 if (a - a0 + 1 > alen || b - b0 + 1 > blen) 1606 return 0; 1607 1608 if ((signed char)a[0] < 0 || (signed char)b[0] < 0) 1609 return 0; 1610 /* we don't support compression yet */ 1611 if (a[0] >= 64 || b[0] >= 64) 1612 return 0; 1613 1614 /* truncated case */ 1615 if (a[0] == 0 && a - a0 == alen - 1) 1616 return 1; 1617 if (b[0] == 0 && b - b0 == blen - 1) 1618 return 1; 1619 if (a[0] == 0 || b[0] == 0) 1620 return 0; 1621 1622 if (a[0] != b[0]) 1623 return 0; 1624 l = a[0]; 1625 if (a - a0 + 1 + l > alen || b - b0 + 1 + l > blen) 1626 return 0; 1627 if (bcmp(a + 1, b + 1, l) != 0) 1628 return 0; 1629 1630 a += 1 + l; 1631 b += 1 + l; 1632 } 1633 1634 if (a - a0 == alen && b - b0 == blen) 1635 return 1; 1636 else 1637 return 0; 1638 } 1639 1640 /* 1641 * calculate the number of addresses to be returned in the node info reply. 1642 */ 1643 static int 1644 ni6_addrs(ni6, m, ifpp, subj) 1645 struct icmp6_nodeinfo *ni6; 1646 struct mbuf *m; 1647 struct ifnet **ifpp; 1648 char *subj; 1649 { 1650 struct ifnet *ifp; 1651 struct in6_ifaddr *ifa6; 1652 struct ifaddr *ifa; 1653 struct sockaddr_in6 *subj_ip6 = NULL; /* XXX pedant */ 1654 int addrs = 0, addrsofif, iffound = 0; 1655 int niflags = ni6->ni_flags; 1656 1657 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0) { 1658 switch (ni6->ni_code) { 1659 case ICMP6_NI_SUBJ_IPV6: 1660 if (subj == NULL) /* must be impossible... */ 1661 return (0); 1662 subj_ip6 = (struct sockaddr_in6 *)subj; 1663 break; 1664 default: 1665 /* 1666 * XXX: we only support IPv6 subject address for 1667 * this Qtype. 1668 */ 1669 return (0); 1670 } 1671 } 1672 1673 IFNET_RLOCK(); 1674 for (ifp = TAILQ_FIRST(&ifnet); ifp; ifp = TAILQ_NEXT(ifp, if_list)) { 1675 addrsofif = 0; 1676 TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list) { 1677 if (ifa->ifa_addr->sa_family != AF_INET6) 1678 continue; 1679 ifa6 = (struct in6_ifaddr *)ifa; 1680 1681 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0 && 1682 IN6_ARE_ADDR_EQUAL(&subj_ip6->sin6_addr, 1683 &ifa6->ia_addr.sin6_addr)) 1684 iffound = 1; 1685 1686 /* 1687 * IPv4-mapped addresses can only be returned by a 1688 * Node Information proxy, since they represent 1689 * addresses of IPv4-only nodes, which perforce do 1690 * not implement this protocol. 1691 * [icmp-name-lookups-07, Section 5.4] 1692 * So we don't support NI_NODEADDR_FLAG_COMPAT in 1693 * this function at this moment. 1694 */ 1695 1696 /* What do we have to do about ::1? */ 1697 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1698 case IPV6_ADDR_SCOPE_LINKLOCAL: 1699 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0) 1700 continue; 1701 break; 1702 case IPV6_ADDR_SCOPE_SITELOCAL: 1703 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0) 1704 continue; 1705 break; 1706 case IPV6_ADDR_SCOPE_GLOBAL: 1707 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0) 1708 continue; 1709 break; 1710 default: 1711 continue; 1712 } 1713 1714 /* 1715 * check if anycast is okay. 1716 * XXX: just experimental. not in the spec. 1717 */ 1718 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 && 1719 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0) 1720 continue; /* we need only unicast addresses */ 1721 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 1722 (icmp6_nodeinfo & 4) == 0) { 1723 continue; 1724 } 1725 addrsofif++; /* count the address */ 1726 } 1727 if (iffound) { 1728 *ifpp = ifp; 1729 IFNET_RUNLOCK(); 1730 return (addrsofif); 1731 } 1732 1733 addrs += addrsofif; 1734 } 1735 IFNET_RUNLOCK(); 1736 1737 return (addrs); 1738 } 1739 1740 static int 1741 ni6_store_addrs(ni6, nni6, ifp0, resid) 1742 struct icmp6_nodeinfo *ni6, *nni6; 1743 struct ifnet *ifp0; 1744 int resid; 1745 { 1746 struct ifnet *ifp = ifp0 ? ifp0 : TAILQ_FIRST(&ifnet); 1747 struct in6_ifaddr *ifa6; 1748 struct ifaddr *ifa; 1749 struct ifnet *ifp_dep = NULL; 1750 int copied = 0, allow_deprecated = 0; 1751 u_char *cp = (u_char *)(nni6 + 1); 1752 int niflags = ni6->ni_flags; 1753 u_int32_t ltime; 1754 1755 if (ifp0 == NULL && !(niflags & NI_NODEADDR_FLAG_ALL)) 1756 return (0); /* needless to copy */ 1757 1758 IFNET_RLOCK(); 1759 again: 1760 1761 for (; ifp; ifp = TAILQ_NEXT(ifp, if_list)) { 1762 for (ifa = ifp->if_addrlist.tqh_first; ifa; 1763 ifa = ifa->ifa_list.tqe_next) { 1764 if (ifa->ifa_addr->sa_family != AF_INET6) 1765 continue; 1766 ifa6 = (struct in6_ifaddr *)ifa; 1767 1768 if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) != 0 && 1769 allow_deprecated == 0) { 1770 /* 1771 * prefererred address should be put before 1772 * deprecated addresses. 1773 */ 1774 1775 /* record the interface for later search */ 1776 if (ifp_dep == NULL) 1777 ifp_dep = ifp; 1778 1779 continue; 1780 } else if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) == 0 && 1781 allow_deprecated != 0) 1782 continue; /* we now collect deprecated addrs */ 1783 1784 /* What do we have to do about ::1? */ 1785 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1786 case IPV6_ADDR_SCOPE_LINKLOCAL: 1787 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0) 1788 continue; 1789 break; 1790 case IPV6_ADDR_SCOPE_SITELOCAL: 1791 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0) 1792 continue; 1793 break; 1794 case IPV6_ADDR_SCOPE_GLOBAL: 1795 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0) 1796 continue; 1797 break; 1798 default: 1799 continue; 1800 } 1801 1802 /* 1803 * check if anycast is okay. 1804 * XXX: just experimental. not in the spec. 1805 */ 1806 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 && 1807 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0) 1808 continue; 1809 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 1810 (icmp6_nodeinfo & 4) == 0) { 1811 continue; 1812 } 1813 1814 /* now we can copy the address */ 1815 if (resid < sizeof(struct in6_addr) + 1816 sizeof(u_int32_t)) { 1817 /* 1818 * We give up much more copy. 1819 * Set the truncate flag and return. 1820 */ 1821 nni6->ni_flags |= NI_NODEADDR_FLAG_TRUNCATE; 1822 IFNET_RUNLOCK(); 1823 return (copied); 1824 } 1825 1826 /* 1827 * Set the TTL of the address. 1828 * The TTL value should be one of the following 1829 * according to the specification: 1830 * 1831 * 1. The remaining lifetime of a DHCP lease on the 1832 * address, or 1833 * 2. The remaining Valid Lifetime of a prefix from 1834 * which the address was derived through Stateless 1835 * Autoconfiguration. 1836 * 1837 * Note that we currently do not support stateful 1838 * address configuration by DHCPv6, so the former 1839 * case can't happen. 1840 */ 1841 if (ifa6->ia6_lifetime.ia6t_expire == 0) 1842 ltime = ND6_INFINITE_LIFETIME; 1843 else { 1844 if (ifa6->ia6_lifetime.ia6t_expire > 1845 time_second) 1846 ltime = htonl(ifa6->ia6_lifetime.ia6t_expire - time_second); 1847 else 1848 ltime = 0; 1849 } 1850 1851 bcopy(<ime, cp, sizeof(u_int32_t)); 1852 cp += sizeof(u_int32_t); 1853 1854 /* copy the address itself */ 1855 bcopy(&ifa6->ia_addr.sin6_addr, cp, 1856 sizeof(struct in6_addr)); 1857 in6_clearscope((struct in6_addr *)cp); /* XXX */ 1858 cp += sizeof(struct in6_addr); 1859 1860 resid -= (sizeof(struct in6_addr) + sizeof(u_int32_t)); 1861 copied += (sizeof(struct in6_addr) + sizeof(u_int32_t)); 1862 } 1863 if (ifp0) /* we need search only on the specified IF */ 1864 break; 1865 } 1866 1867 if (allow_deprecated == 0 && ifp_dep != NULL) { 1868 ifp = ifp_dep; 1869 allow_deprecated = 1; 1870 1871 goto again; 1872 } 1873 1874 IFNET_RUNLOCK(); 1875 1876 return (copied); 1877 } 1878 1879 /* 1880 * XXX almost dup'ed code with rip6_input. 1881 */ 1882 static int 1883 icmp6_rip6_input(mp, off) 1884 struct mbuf **mp; 1885 int off; 1886 { 1887 struct mbuf *m = *mp; 1888 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1889 struct in6pcb *in6p; 1890 struct in6pcb *last = NULL; 1891 struct sockaddr_in6 fromsa; 1892 struct icmp6_hdr *icmp6; 1893 struct mbuf *opts = NULL; 1894 1895 #ifndef PULLDOWN_TEST 1896 /* this is assumed to be safe. */ 1897 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off); 1898 #else 1899 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 1900 if (icmp6 == NULL) { 1901 /* m is already reclaimed */ 1902 return (IPPROTO_DONE); 1903 } 1904 #endif 1905 1906 bzero(&fromsa, sizeof(fromsa)); 1907 fromsa.sin6_len = sizeof(struct sockaddr_in6); 1908 fromsa.sin6_family = AF_INET6; 1909 /* KAME hack: recover scopeid */ 1910 (void)in6_recoverscope(&fromsa, &ip6->ip6_src, m->m_pkthdr.rcvif); 1911 1912 LIST_FOREACH(in6p, &ripcb, inp_list) { 1913 if ((in6p->inp_vflag & INP_IPV6) == 0) 1914 continue; 1915 if (in6p->in6p_ip6_nxt != IPPROTO_ICMPV6) 1916 continue; 1917 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr) && 1918 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr, &ip6->ip6_dst)) 1919 continue; 1920 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr) && 1921 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr, &ip6->ip6_src)) 1922 continue; 1923 if (in6p->in6p_icmp6filt 1924 && ICMP6_FILTER_WILLBLOCK(icmp6->icmp6_type, 1925 in6p->in6p_icmp6filt)) 1926 continue; 1927 if (last) { 1928 struct mbuf *n = NULL; 1929 1930 /* 1931 * Recent network drivers tend to allocate a single 1932 * mbuf cluster, rather than to make a couple of 1933 * mbufs without clusters. Also, since the IPv6 code 1934 * path tries to avoid m_pullup(), it is highly 1935 * probable that we still have an mbuf cluster here 1936 * even though the necessary length can be stored in an 1937 * mbuf's internal buffer. 1938 * Meanwhile, the default size of the receive socket 1939 * buffer for raw sockets is not so large. This means 1940 * the possibility of packet loss is relatively higher 1941 * than before. To avoid this scenario, we copy the 1942 * received data to a separate mbuf that does not use 1943 * a cluster, if possible. 1944 * XXX: it is better to copy the data after stripping 1945 * intermediate headers. 1946 */ 1947 if ((m->m_flags & M_EXT) && m->m_next == NULL && 1948 m->m_len <= MHLEN) { 1949 MGET(n, M_DONTWAIT, m->m_type); 1950 if (n != NULL) { 1951 m_dup_pkthdr(n, m, M_NOWAIT); 1952 bcopy(m->m_data, n->m_data, m->m_len); 1953 n->m_len = m->m_len; 1954 } 1955 } 1956 if (n != NULL || 1957 (n = m_copy(m, 0, (int)M_COPYALL)) != NULL) { 1958 if (last->in6p_flags & IN6P_CONTROLOPTS) 1959 ip6_savecontrol(last, n, &opts); 1960 /* strip intermediate headers */ 1961 m_adj(n, off); 1962 if (sbappendaddr(&last->in6p_socket->so_rcv, 1963 (struct sockaddr *)&fromsa, n, opts) 1964 == 0) { 1965 /* should notify about lost packet */ 1966 m_freem(n); 1967 if (opts) { 1968 m_freem(opts); 1969 } 1970 } else 1971 sorwakeup(last->in6p_socket); 1972 opts = NULL; 1973 } 1974 } 1975 last = in6p; 1976 } 1977 if (last) { 1978 if (last->in6p_flags & IN6P_CONTROLOPTS) 1979 ip6_savecontrol(last, m, &opts); 1980 /* strip intermediate headers */ 1981 m_adj(m, off); 1982 1983 /* avoid using mbuf clusters if possible (see above) */ 1984 if ((m->m_flags & M_EXT) && m->m_next == NULL && 1985 m->m_len <= MHLEN) { 1986 struct mbuf *n; 1987 1988 MGET(n, M_DONTWAIT, m->m_type); 1989 if (n != NULL) { 1990 m_dup_pkthdr(n, m, M_NOWAIT); 1991 bcopy(m->m_data, n->m_data, m->m_len); 1992 n->m_len = m->m_len; 1993 1994 m_freem(m); 1995 m = n; 1996 } 1997 } 1998 if (sbappendaddr(&last->in6p_socket->so_rcv, 1999 (struct sockaddr *)&fromsa, m, opts) == 0) { 2000 m_freem(m); 2001 if (opts) 2002 m_freem(opts); 2003 } else 2004 sorwakeup(last->in6p_socket); 2005 } else { 2006 m_freem(m); 2007 ip6stat.ip6s_delivered--; 2008 } 2009 return IPPROTO_DONE; 2010 } 2011 2012 /* 2013 * Reflect the ip6 packet back to the source. 2014 * OFF points to the icmp6 header, counted from the top of the mbuf. 2015 */ 2016 void 2017 icmp6_reflect(m, off) 2018 struct mbuf *m; 2019 size_t off; 2020 { 2021 struct ip6_hdr *ip6; 2022 struct icmp6_hdr *icmp6; 2023 struct in6_ifaddr *ia; 2024 struct in6_addr t, *src = 0; 2025 int plen; 2026 int type, code; 2027 struct ifnet *outif = NULL; 2028 struct sockaddr_in6 sa6_src, sa6_dst; 2029 #ifdef COMPAT_RFC1885 2030 int mtu = IPV6_MMTU; 2031 struct sockaddr_in6 *sin6 = &icmp6_reflect_rt.ro_dst; 2032 #endif 2033 2034 /* too short to reflect */ 2035 if (off < sizeof(struct ip6_hdr)) { 2036 nd6log((LOG_DEBUG, 2037 "sanity fail: off=%lx, sizeof(ip6)=%lx in %s:%d\n", 2038 (u_long)off, (u_long)sizeof(struct ip6_hdr), 2039 __FILE__, __LINE__)); 2040 goto bad; 2041 } 2042 2043 /* 2044 * If there are extra headers between IPv6 and ICMPv6, strip 2045 * off that header first. 2046 */ 2047 #ifdef DIAGNOSTIC 2048 if (sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) > MHLEN) 2049 panic("assumption failed in icmp6_reflect"); 2050 #endif 2051 if (off > sizeof(struct ip6_hdr)) { 2052 size_t l; 2053 struct ip6_hdr nip6; 2054 2055 l = off - sizeof(struct ip6_hdr); 2056 m_copydata(m, 0, sizeof(nip6), (caddr_t)&nip6); 2057 m_adj(m, l); 2058 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 2059 if (m->m_len < l) { 2060 if ((m = m_pullup(m, l)) == NULL) 2061 return; 2062 } 2063 bcopy((caddr_t)&nip6, mtod(m, caddr_t), sizeof(nip6)); 2064 } else /* off == sizeof(struct ip6_hdr) */ { 2065 size_t l; 2066 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 2067 if (m->m_len < l) { 2068 if ((m = m_pullup(m, l)) == NULL) 2069 return; 2070 } 2071 } 2072 plen = m->m_pkthdr.len - sizeof(struct ip6_hdr); 2073 ip6 = mtod(m, struct ip6_hdr *); 2074 ip6->ip6_nxt = IPPROTO_ICMPV6; 2075 icmp6 = (struct icmp6_hdr *)(ip6 + 1); 2076 type = icmp6->icmp6_type; /* keep type for statistics */ 2077 code = icmp6->icmp6_code; /* ditto. */ 2078 2079 t = ip6->ip6_dst; 2080 /* 2081 * ip6_input() drops a packet if its src is multicast. 2082 * So, the src is never multicast. 2083 */ 2084 ip6->ip6_dst = ip6->ip6_src; 2085 2086 /* 2087 * XXX: make sure to embed scope zone information, using 2088 * already embedded IDs or the received interface (if any). 2089 * Note that rcvif may be NULL. 2090 * TODO: scoped routing case (XXX). 2091 */ 2092 bzero(&sa6_src, sizeof(sa6_src)); 2093 sa6_src.sin6_family = AF_INET6; 2094 sa6_src.sin6_len = sizeof(sa6_src); 2095 sa6_src.sin6_addr = ip6->ip6_dst; 2096 in6_recoverscope(&sa6_src, &ip6->ip6_dst, m->m_pkthdr.rcvif); 2097 in6_embedscope(&ip6->ip6_dst, &sa6_src, NULL, NULL); 2098 bzero(&sa6_dst, sizeof(sa6_dst)); 2099 sa6_dst.sin6_family = AF_INET6; 2100 sa6_dst.sin6_len = sizeof(sa6_dst); 2101 sa6_dst.sin6_addr = t; 2102 in6_recoverscope(&sa6_dst, &t, m->m_pkthdr.rcvif); 2103 in6_embedscope(&t, &sa6_dst, NULL, NULL); 2104 2105 #ifdef COMPAT_RFC1885 2106 /* 2107 * xxx guess MTU 2108 * RFC 1885 requires that echo reply should be truncated if it 2109 * does not fit in with (return) path MTU, but the description was 2110 * removed in the new spec. 2111 */ 2112 if (icmp6_reflect_rt.ro_rt == 0 || 2113 ! (IN6_ARE_ADDR_EQUAL(&sin6->sin6_addr, &ip6->ip6_dst))) { 2114 if (icmp6_reflect_rt.ro_rt) { 2115 RTFREE(icmp6_reflect_rt.ro_rt); 2116 icmp6_reflect_rt.ro_rt = 0; 2117 } 2118 bzero(sin6, sizeof(*sin6)); 2119 sin6->sin6_family = PF_INET6; 2120 sin6->sin6_len = sizeof(struct sockaddr_in6); 2121 sin6->sin6_addr = ip6->ip6_dst; 2122 2123 rtalloc((struct route *)&icmp6_reflect_rt.ro_rt); 2124 } 2125 2126 if (icmp6_reflect_rt.ro_rt == 0) 2127 goto bad; 2128 2129 if ((icmp6_reflect_rt.ro_rt->rt_flags & RTF_HOST) 2130 && mtu < icmp6_reflect_rt.ro_rt->rt_ifp->if_mtu) 2131 mtu = icmp6_reflect_rt.ro_rt->rt_rmx.rmx_mtu; 2132 2133 if (mtu < m->m_pkthdr.len) { 2134 plen -= (m->m_pkthdr.len - mtu); 2135 m_adj(m, mtu - m->m_pkthdr.len); 2136 } 2137 #endif 2138 /* 2139 * If the incoming packet was addressed directly to us (i.e. unicast), 2140 * use dst as the src for the reply. 2141 * The IN6_IFF_NOTREADY case should be VERY rare, but is possible 2142 * (for example) when we encounter an error while forwarding procedure 2143 * destined to a duplicated address of ours. 2144 */ 2145 for (ia = in6_ifaddr; ia; ia = ia->ia_next) 2146 if (IN6_ARE_ADDR_EQUAL(&t, &ia->ia_addr.sin6_addr) && 2147 (ia->ia6_flags & (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY)) == 0) { 2148 src = &t; 2149 break; 2150 } 2151 if (ia == NULL && IN6_IS_ADDR_LINKLOCAL(&t) && (m->m_flags & M_LOOP)) { 2152 /* 2153 * This is the case if the dst is our link-local address 2154 * and the sender is also ourselves. 2155 */ 2156 src = &t; 2157 } 2158 2159 if (src == 0) { 2160 int e; 2161 struct route_in6 ro; 2162 2163 /* 2164 * This case matches to multicasts, our anycast, or unicasts 2165 * that we do not own. Select a source address based on the 2166 * source address of the erroneous packet. 2167 */ 2168 bzero(&ro, sizeof(ro)); 2169 src = in6_selectsrc(&sa6_src, NULL, NULL, &ro, NULL, &e); 2170 if (ro.ro_rt) 2171 RTFREE(ro.ro_rt); /* XXX: we could use this */ 2172 if (src == NULL) { 2173 nd6log((LOG_DEBUG, 2174 "icmp6_reflect: source can't be determined: " 2175 "dst=%s, error=%d\n", 2176 ip6_sprintf(&sa6_src.sin6_addr), e)); 2177 goto bad; 2178 } 2179 } 2180 2181 ip6->ip6_src = *src; 2182 2183 ip6->ip6_flow = 0; 2184 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2185 ip6->ip6_vfc |= IPV6_VERSION; 2186 ip6->ip6_nxt = IPPROTO_ICMPV6; 2187 if (outif) 2188 ip6->ip6_hlim = ND_IFINFO(outif)->chlim; 2189 else if (m->m_pkthdr.rcvif) { 2190 /* XXX: This may not be the outgoing interface */ 2191 ip6->ip6_hlim = ND_IFINFO(m->m_pkthdr.rcvif)->chlim; 2192 } else 2193 ip6->ip6_hlim = ip6_defhlim; 2194 2195 icmp6->icmp6_cksum = 0; 2196 icmp6->icmp6_cksum = in6_cksum(m, IPPROTO_ICMPV6, 2197 sizeof(struct ip6_hdr), plen); 2198 2199 /* 2200 * XXX option handling 2201 */ 2202 2203 m->m_flags &= ~(M_BCAST|M_MCAST); 2204 2205 #ifdef COMPAT_RFC1885 2206 ip6_output(m, NULL, &icmp6_reflect_rt, 0, NULL, &outif, NULL); 2207 #else 2208 ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL); 2209 #endif 2210 if (outif) 2211 icmp6_ifoutstat_inc(outif, type, code); 2212 2213 return; 2214 2215 bad: 2216 m_freem(m); 2217 return; 2218 } 2219 2220 void 2221 icmp6_fasttimo() 2222 { 2223 2224 mld6_fasttimeo(); 2225 } 2226 2227 static const char * 2228 icmp6_redirect_diag(src6, dst6, tgt6) 2229 struct in6_addr *src6; 2230 struct in6_addr *dst6; 2231 struct in6_addr *tgt6; 2232 { 2233 static char buf[1024]; 2234 snprintf(buf, sizeof(buf), "(src=%s dst=%s tgt=%s)", 2235 ip6_sprintf(src6), ip6_sprintf(dst6), ip6_sprintf(tgt6)); 2236 return buf; 2237 } 2238 2239 void 2240 icmp6_redirect_input(m, off) 2241 struct mbuf *m; 2242 int off; 2243 { 2244 struct ifnet *ifp = m->m_pkthdr.rcvif; 2245 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 2246 struct nd_redirect *nd_rd; 2247 int icmp6len = ntohs(ip6->ip6_plen); 2248 char *lladdr = NULL; 2249 int lladdrlen = 0; 2250 u_char *redirhdr = NULL; 2251 int redirhdrlen = 0; 2252 struct rtentry *rt = NULL; 2253 int is_router; 2254 int is_onlink; 2255 struct in6_addr src6 = ip6->ip6_src; 2256 struct in6_addr redtgt6; 2257 struct in6_addr reddst6; 2258 union nd_opts ndopts; 2259 2260 if (!m || !ifp) 2261 return; 2262 2263 /* XXX if we are router, we don't update route by icmp6 redirect */ 2264 if (ip6_forwarding) 2265 goto freeit; 2266 if (!icmp6_rediraccept) 2267 goto freeit; 2268 2269 #ifndef PULLDOWN_TEST 2270 IP6_EXTHDR_CHECK(m, off, icmp6len,); 2271 nd_rd = (struct nd_redirect *)((caddr_t)ip6 + off); 2272 #else 2273 IP6_EXTHDR_GET(nd_rd, struct nd_redirect *, m, off, icmp6len); 2274 if (nd_rd == NULL) { 2275 icmp6stat.icp6s_tooshort++; 2276 return; 2277 } 2278 #endif 2279 redtgt6 = nd_rd->nd_rd_target; 2280 reddst6 = nd_rd->nd_rd_dst; 2281 2282 if (IN6_IS_ADDR_LINKLOCAL(&redtgt6)) 2283 redtgt6.s6_addr16[1] = htons(ifp->if_index); 2284 if (IN6_IS_ADDR_LINKLOCAL(&reddst6)) 2285 reddst6.s6_addr16[1] = htons(ifp->if_index); 2286 2287 /* validation */ 2288 if (!IN6_IS_ADDR_LINKLOCAL(&src6)) { 2289 nd6log((LOG_ERR, 2290 "ICMP6 redirect sent from %s rejected; " 2291 "must be from linklocal\n", 2292 ip6_sprintf(&src6))); 2293 goto bad; 2294 } 2295 if (ip6->ip6_hlim != 255) { 2296 nd6log((LOG_ERR, 2297 "ICMP6 redirect sent from %s rejected; " 2298 "hlim=%d (must be 255)\n", 2299 ip6_sprintf(&src6), ip6->ip6_hlim)); 2300 goto bad; 2301 } 2302 { 2303 /* ip6->ip6_src must be equal to gw for icmp6->icmp6_reddst */ 2304 struct sockaddr_in6 sin6; 2305 struct in6_addr *gw6; 2306 2307 bzero(&sin6, sizeof(sin6)); 2308 sin6.sin6_family = AF_INET6; 2309 sin6.sin6_len = sizeof(struct sockaddr_in6); 2310 bcopy(&reddst6, &sin6.sin6_addr, sizeof(reddst6)); 2311 rt = rtalloc1((struct sockaddr *)&sin6, 0, 0UL); 2312 if (rt) { 2313 if (rt->rt_gateway == NULL || 2314 rt->rt_gateway->sa_family != AF_INET6) { 2315 nd6log((LOG_ERR, 2316 "ICMP6 redirect rejected; no route " 2317 "with inet6 gateway found for redirect dst: %s\n", 2318 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2319 RTFREE_LOCKED(rt); 2320 goto bad; 2321 } 2322 2323 gw6 = &(((struct sockaddr_in6 *)rt->rt_gateway)->sin6_addr); 2324 if (bcmp(&src6, gw6, sizeof(struct in6_addr)) != 0) { 2325 nd6log((LOG_ERR, 2326 "ICMP6 redirect rejected; " 2327 "not equal to gw-for-src=%s (must be same): " 2328 "%s\n", 2329 ip6_sprintf(gw6), 2330 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2331 RTFREE_LOCKED(rt); 2332 goto bad; 2333 } 2334 } else { 2335 nd6log((LOG_ERR, 2336 "ICMP6 redirect rejected; " 2337 "no route found for redirect dst: %s\n", 2338 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2339 goto bad; 2340 } 2341 RTFREE_LOCKED(rt); 2342 rt = NULL; 2343 } 2344 if (IN6_IS_ADDR_MULTICAST(&reddst6)) { 2345 nd6log((LOG_ERR, 2346 "ICMP6 redirect rejected; " 2347 "redirect dst must be unicast: %s\n", 2348 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2349 goto bad; 2350 } 2351 2352 is_router = is_onlink = 0; 2353 if (IN6_IS_ADDR_LINKLOCAL(&redtgt6)) 2354 is_router = 1; /* router case */ 2355 if (bcmp(&redtgt6, &reddst6, sizeof(redtgt6)) == 0) 2356 is_onlink = 1; /* on-link destination case */ 2357 if (!is_router && !is_onlink) { 2358 nd6log((LOG_ERR, 2359 "ICMP6 redirect rejected; " 2360 "neither router case nor onlink case: %s\n", 2361 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2362 goto bad; 2363 } 2364 /* validation passed */ 2365 2366 icmp6len -= sizeof(*nd_rd); 2367 nd6_option_init(nd_rd + 1, icmp6len, &ndopts); 2368 if (nd6_options(&ndopts) < 0) { 2369 nd6log((LOG_INFO, "icmp6_redirect_input: " 2370 "invalid ND option, rejected: %s\n", 2371 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2372 /* nd6_options have incremented stats */ 2373 goto freeit; 2374 } 2375 2376 if (ndopts.nd_opts_tgt_lladdr) { 2377 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 2378 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 2379 } 2380 2381 if (ndopts.nd_opts_rh) { 2382 redirhdrlen = ndopts.nd_opts_rh->nd_opt_rh_len; 2383 redirhdr = (u_char *)(ndopts.nd_opts_rh + 1); /* xxx */ 2384 } 2385 2386 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 2387 nd6log((LOG_INFO, 2388 "icmp6_redirect_input: lladdrlen mismatch for %s " 2389 "(if %d, icmp6 packet %d): %s\n", 2390 ip6_sprintf(&redtgt6), ifp->if_addrlen, lladdrlen - 2, 2391 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2392 goto bad; 2393 } 2394 2395 /* RFC 2461 8.3 */ 2396 nd6_cache_lladdr(ifp, &redtgt6, lladdr, lladdrlen, ND_REDIRECT, 2397 is_onlink ? ND_REDIRECT_ONLINK : ND_REDIRECT_ROUTER); 2398 2399 if (!is_onlink) { /* better router case. perform rtredirect. */ 2400 /* perform rtredirect */ 2401 struct sockaddr_in6 sdst; 2402 struct sockaddr_in6 sgw; 2403 struct sockaddr_in6 ssrc; 2404 2405 bzero(&sdst, sizeof(sdst)); 2406 bzero(&sgw, sizeof(sgw)); 2407 bzero(&ssrc, sizeof(ssrc)); 2408 sdst.sin6_family = sgw.sin6_family = ssrc.sin6_family = AF_INET6; 2409 sdst.sin6_len = sgw.sin6_len = ssrc.sin6_len = 2410 sizeof(struct sockaddr_in6); 2411 bcopy(&redtgt6, &sgw.sin6_addr, sizeof(struct in6_addr)); 2412 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2413 bcopy(&src6, &ssrc.sin6_addr, sizeof(struct in6_addr)); 2414 rtredirect((struct sockaddr *)&sdst, (struct sockaddr *)&sgw, 2415 (struct sockaddr *)NULL, RTF_GATEWAY | RTF_HOST, 2416 (struct sockaddr *)&ssrc); 2417 } 2418 /* finally update cached route in each socket via pfctlinput */ 2419 { 2420 struct sockaddr_in6 sdst; 2421 2422 bzero(&sdst, sizeof(sdst)); 2423 sdst.sin6_family = AF_INET6; 2424 sdst.sin6_len = sizeof(struct sockaddr_in6); 2425 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2426 pfctlinput(PRC_REDIRECT_HOST, (struct sockaddr *)&sdst); 2427 #if defined(IPSEC) || defined(FAST_IPSEC) 2428 key_sa_routechange((struct sockaddr *)&sdst); 2429 #endif 2430 } 2431 2432 freeit: 2433 m_freem(m); 2434 return; 2435 2436 bad: 2437 icmp6stat.icp6s_badredirect++; 2438 m_freem(m); 2439 } 2440 2441 void 2442 icmp6_redirect_output(m0, rt) 2443 struct mbuf *m0; 2444 struct rtentry *rt; 2445 { 2446 struct ifnet *ifp; /* my outgoing interface */ 2447 struct in6_addr *ifp_ll6; 2448 struct in6_addr *router_ll6; 2449 struct ip6_hdr *sip6; /* m0 as struct ip6_hdr */ 2450 struct mbuf *m = NULL; /* newly allocated one */ 2451 struct ip6_hdr *ip6; /* m as struct ip6_hdr */ 2452 struct nd_redirect *nd_rd; 2453 size_t maxlen; 2454 u_char *p; 2455 struct ifnet *outif = NULL; 2456 struct sockaddr_in6 src_sa; 2457 2458 icmp6_errcount(&icmp6stat.icp6s_outerrhist, ND_REDIRECT, 0); 2459 2460 /* if we are not router, we don't send icmp6 redirect */ 2461 if (!ip6_forwarding || ip6_accept_rtadv) 2462 goto fail; 2463 2464 /* sanity check */ 2465 if (!m0 || !rt || !(rt->rt_flags & RTF_UP) || !(ifp = rt->rt_ifp)) 2466 goto fail; 2467 2468 /* 2469 * Address check: 2470 * the source address must identify a neighbor, and 2471 * the destination address must not be a multicast address 2472 * [RFC 2461, sec 8.2] 2473 */ 2474 sip6 = mtod(m0, struct ip6_hdr *); 2475 bzero(&src_sa, sizeof(src_sa)); 2476 src_sa.sin6_family = AF_INET6; 2477 src_sa.sin6_len = sizeof(src_sa); 2478 src_sa.sin6_addr = sip6->ip6_src; 2479 /* we don't currently use sin6_scope_id, but eventually use it */ 2480 if (in6_addr2zoneid(ifp, &sip6->ip6_src, &src_sa.sin6_scope_id)) 2481 goto fail; 2482 if (nd6_is_addr_neighbor(&src_sa, ifp) == 0) 2483 goto fail; 2484 if (IN6_IS_ADDR_MULTICAST(&sip6->ip6_dst)) 2485 goto fail; /* what should we do here? */ 2486 2487 /* rate limit */ 2488 if (icmp6_ratelimit(&sip6->ip6_src, ND_REDIRECT, 0)) 2489 goto fail; 2490 2491 /* 2492 * Since we are going to append up to 1280 bytes (= IPV6_MMTU), 2493 * we almost always ask for an mbuf cluster for simplicity. 2494 * (MHLEN < IPV6_MMTU is almost always true) 2495 */ 2496 #if IPV6_MMTU >= MCLBYTES 2497 # error assumption failed about IPV6_MMTU and MCLBYTES 2498 #endif 2499 MGETHDR(m, M_DONTWAIT, MT_HEADER); 2500 if (m && IPV6_MMTU >= MHLEN) 2501 MCLGET(m, M_DONTWAIT); 2502 if (!m) 2503 goto fail; 2504 m->m_pkthdr.rcvif = NULL; 2505 m->m_len = 0; 2506 maxlen = M_TRAILINGSPACE(m); 2507 maxlen = min(IPV6_MMTU, maxlen); 2508 /* just for safety */ 2509 if (maxlen < sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) + 2510 ((sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7)) { 2511 goto fail; 2512 } 2513 2514 { 2515 /* get ip6 linklocal address for ifp(my outgoing interface). */ 2516 struct in6_ifaddr *ia; 2517 if ((ia = in6ifa_ifpforlinklocal(ifp, 2518 IN6_IFF_NOTREADY| 2519 IN6_IFF_ANYCAST)) == NULL) 2520 goto fail; 2521 ifp_ll6 = &ia->ia_addr.sin6_addr; 2522 } 2523 2524 /* get ip6 linklocal address for the router. */ 2525 if (rt->rt_gateway && (rt->rt_flags & RTF_GATEWAY)) { 2526 struct sockaddr_in6 *sin6; 2527 sin6 = (struct sockaddr_in6 *)rt->rt_gateway; 2528 router_ll6 = &sin6->sin6_addr; 2529 if (!IN6_IS_ADDR_LINKLOCAL(router_ll6)) 2530 router_ll6 = (struct in6_addr *)NULL; 2531 } else 2532 router_ll6 = (struct in6_addr *)NULL; 2533 2534 /* ip6 */ 2535 ip6 = mtod(m, struct ip6_hdr *); 2536 ip6->ip6_flow = 0; 2537 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2538 ip6->ip6_vfc |= IPV6_VERSION; 2539 /* ip6->ip6_plen will be set later */ 2540 ip6->ip6_nxt = IPPROTO_ICMPV6; 2541 ip6->ip6_hlim = 255; 2542 /* ip6->ip6_src must be linklocal addr for my outgoing if. */ 2543 bcopy(ifp_ll6, &ip6->ip6_src, sizeof(struct in6_addr)); 2544 bcopy(&sip6->ip6_src, &ip6->ip6_dst, sizeof(struct in6_addr)); 2545 2546 /* ND Redirect */ 2547 nd_rd = (struct nd_redirect *)(ip6 + 1); 2548 nd_rd->nd_rd_type = ND_REDIRECT; 2549 nd_rd->nd_rd_code = 0; 2550 nd_rd->nd_rd_reserved = 0; 2551 if (rt->rt_flags & RTF_GATEWAY) { 2552 /* 2553 * nd_rd->nd_rd_target must be a link-local address in 2554 * better router cases. 2555 */ 2556 if (!router_ll6) 2557 goto fail; 2558 bcopy(router_ll6, &nd_rd->nd_rd_target, 2559 sizeof(nd_rd->nd_rd_target)); 2560 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2561 sizeof(nd_rd->nd_rd_dst)); 2562 } else { 2563 /* make sure redtgt == reddst */ 2564 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_target, 2565 sizeof(nd_rd->nd_rd_target)); 2566 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2567 sizeof(nd_rd->nd_rd_dst)); 2568 } 2569 2570 p = (u_char *)(nd_rd + 1); 2571 2572 if (!router_ll6) 2573 goto nolladdropt; 2574 2575 { 2576 /* target lladdr option */ 2577 struct rtentry *rt_router = NULL; 2578 int len; 2579 struct sockaddr_dl *sdl; 2580 struct nd_opt_hdr *nd_opt; 2581 char *lladdr; 2582 2583 rt_router = nd6_lookup(router_ll6, 0, ifp); 2584 if (!rt_router) 2585 goto nolladdropt; 2586 len = sizeof(*nd_opt) + ifp->if_addrlen; 2587 len = (len + 7) & ~7; /* round by 8 */ 2588 /* safety check */ 2589 if (len + (p - (u_char *)ip6) > maxlen) 2590 goto nolladdropt; 2591 if (!(rt_router->rt_flags & RTF_GATEWAY) && 2592 (rt_router->rt_flags & RTF_LLINFO) && 2593 (rt_router->rt_gateway->sa_family == AF_LINK) && 2594 (sdl = (struct sockaddr_dl *)rt_router->rt_gateway) && 2595 sdl->sdl_alen) { 2596 nd_opt = (struct nd_opt_hdr *)p; 2597 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 2598 nd_opt->nd_opt_len = len >> 3; 2599 lladdr = (char *)(nd_opt + 1); 2600 bcopy(LLADDR(sdl), lladdr, ifp->if_addrlen); 2601 p += len; 2602 } 2603 } 2604 nolladdropt:; 2605 2606 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2607 2608 /* just to be safe */ 2609 #ifdef M_DECRYPTED /*not openbsd*/ 2610 if (m0->m_flags & M_DECRYPTED) 2611 goto noredhdropt; 2612 #endif 2613 if (p - (u_char *)ip6 > maxlen) 2614 goto noredhdropt; 2615 2616 { 2617 /* redirected header option */ 2618 int len; 2619 struct nd_opt_rd_hdr *nd_opt_rh; 2620 2621 /* 2622 * compute the maximum size for icmp6 redirect header option. 2623 * XXX room for auth header? 2624 */ 2625 len = maxlen - (p - (u_char *)ip6); 2626 len &= ~7; 2627 2628 /* This is just for simplicity. */ 2629 if (m0->m_pkthdr.len != m0->m_len) { 2630 if (m0->m_next) { 2631 m_freem(m0->m_next); 2632 m0->m_next = NULL; 2633 } 2634 m0->m_pkthdr.len = m0->m_len; 2635 } 2636 2637 /* 2638 * Redirected header option spec (RFC2461 4.6.3) talks nothing 2639 * about padding/truncate rule for the original IP packet. 2640 * From the discussion on IPv6imp in Feb 1999, 2641 * the consensus was: 2642 * - "attach as much as possible" is the goal 2643 * - pad if not aligned (original size can be guessed by 2644 * original ip6 header) 2645 * Following code adds the padding if it is simple enough, 2646 * and truncates if not. 2647 */ 2648 if (m0->m_next || m0->m_pkthdr.len != m0->m_len) 2649 panic("assumption failed in %s:%d", __FILE__, 2650 __LINE__); 2651 2652 if (len - sizeof(*nd_opt_rh) < m0->m_pkthdr.len) { 2653 /* not enough room, truncate */ 2654 m0->m_pkthdr.len = m0->m_len = len - 2655 sizeof(*nd_opt_rh); 2656 } else { 2657 /* enough room, pad or truncate */ 2658 size_t extra; 2659 2660 extra = m0->m_pkthdr.len % 8; 2661 if (extra) { 2662 /* pad if easy enough, truncate if not */ 2663 if (8 - extra <= M_TRAILINGSPACE(m0)) { 2664 /* pad */ 2665 m0->m_len += (8 - extra); 2666 m0->m_pkthdr.len += (8 - extra); 2667 } else { 2668 /* truncate */ 2669 m0->m_pkthdr.len -= extra; 2670 m0->m_len -= extra; 2671 } 2672 } 2673 len = m0->m_pkthdr.len + sizeof(*nd_opt_rh); 2674 m0->m_pkthdr.len = m0->m_len = len - 2675 sizeof(*nd_opt_rh); 2676 } 2677 2678 nd_opt_rh = (struct nd_opt_rd_hdr *)p; 2679 bzero(nd_opt_rh, sizeof(*nd_opt_rh)); 2680 nd_opt_rh->nd_opt_rh_type = ND_OPT_REDIRECTED_HEADER; 2681 nd_opt_rh->nd_opt_rh_len = len >> 3; 2682 p += sizeof(*nd_opt_rh); 2683 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2684 2685 /* connect m0 to m */ 2686 m_tag_delete_chain(m0, NULL); 2687 m0->m_flags &= ~M_PKTHDR; 2688 m->m_next = m0; 2689 m->m_pkthdr.len = m->m_len + m0->m_len; 2690 m0 = NULL; 2691 } 2692 noredhdropt:; 2693 if (m0) { 2694 m_freem(m0); 2695 m0 = NULL; 2696 } 2697 2698 /* XXX: clear embedded link IDs in the inner header */ 2699 in6_clearscope(&sip6->ip6_src); 2700 in6_clearscope(&sip6->ip6_dst); 2701 in6_clearscope(&nd_rd->nd_rd_target); 2702 in6_clearscope(&nd_rd->nd_rd_dst); 2703 2704 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr)); 2705 2706 nd_rd->nd_rd_cksum = 0; 2707 nd_rd->nd_rd_cksum = in6_cksum(m, IPPROTO_ICMPV6, 2708 sizeof(*ip6), ntohs(ip6->ip6_plen)); 2709 2710 /* send the packet to outside... */ 2711 ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL); 2712 if (outif) { 2713 icmp6_ifstat_inc(outif, ifs6_out_msg); 2714 icmp6_ifstat_inc(outif, ifs6_out_redirect); 2715 } 2716 icmp6stat.icp6s_outhist[ND_REDIRECT]++; 2717 2718 return; 2719 2720 fail: 2721 if (m) 2722 m_freem(m); 2723 if (m0) 2724 m_freem(m0); 2725 } 2726 2727 /* 2728 * ICMPv6 socket option processing. 2729 */ 2730 int 2731 icmp6_ctloutput(so, sopt) 2732 struct socket *so; 2733 struct sockopt *sopt; 2734 { 2735 int error = 0; 2736 int optlen; 2737 struct inpcb *inp = sotoinpcb(so); 2738 int level, op, optname; 2739 2740 if (sopt) { 2741 level = sopt->sopt_level; 2742 op = sopt->sopt_dir; 2743 optname = sopt->sopt_name; 2744 optlen = sopt->sopt_valsize; 2745 } else 2746 level = op = optname = optlen = 0; 2747 2748 if (level != IPPROTO_ICMPV6) { 2749 return EINVAL; 2750 } 2751 2752 switch (op) { 2753 case PRCO_SETOPT: 2754 switch (optname) { 2755 case ICMP6_FILTER: 2756 { 2757 struct icmp6_filter *p; 2758 2759 if (optlen != sizeof(*p)) { 2760 error = EMSGSIZE; 2761 break; 2762 } 2763 if (inp->in6p_icmp6filt == NULL) { 2764 error = EINVAL; 2765 break; 2766 } 2767 error = sooptcopyin(sopt, inp->in6p_icmp6filt, optlen, 2768 optlen); 2769 break; 2770 } 2771 2772 default: 2773 error = ENOPROTOOPT; 2774 break; 2775 } 2776 break; 2777 2778 case PRCO_GETOPT: 2779 switch (optname) { 2780 case ICMP6_FILTER: 2781 { 2782 if (inp->in6p_icmp6filt == NULL) { 2783 error = EINVAL; 2784 break; 2785 } 2786 error = sooptcopyout(sopt, inp->in6p_icmp6filt, 2787 sizeof(struct icmp6_filter)); 2788 break; 2789 } 2790 2791 default: 2792 error = ENOPROTOOPT; 2793 break; 2794 } 2795 break; 2796 } 2797 2798 return (error); 2799 } 2800 2801 /* 2802 * Perform rate limit check. 2803 * Returns 0 if it is okay to send the icmp6 packet. 2804 * Returns 1 if the router SHOULD NOT send this icmp6 packet due to rate 2805 * limitation. 2806 * 2807 * XXX per-destination/type check necessary? 2808 */ 2809 static int 2810 icmp6_ratelimit(dst, type, code) 2811 const struct in6_addr *dst; /* not used at this moment */ 2812 const int type; /* not used at this moment */ 2813 const int code; /* not used at this moment */ 2814 { 2815 int ret; 2816 2817 ret = 0; /* okay to send */ 2818 2819 /* PPS limit */ 2820 if (!ppsratecheck(&icmp6errppslim_last, &icmp6errpps_count, 2821 icmp6errppslim)) { 2822 /* The packet is subject to rate limit */ 2823 ret++; 2824 } 2825 2826 return ret; 2827 } 2828