icmp6.c revision 148892
1/* $FreeBSD: head/sys/netinet6/icmp6.c 148892 2005-08-09 12:24:11Z ume $ */ 2/* $KAME: icmp6.c,v 1.211 2001/04/04 05:56:20 itojun Exp $ */ 3 4/*- 5 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the project nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33/*- 34 * Copyright (c) 1982, 1986, 1988, 1993 35 * The Regents of the University of California. All rights reserved. 36 * 37 * Redistribution and use in source and binary forms, with or without 38 * modification, are permitted provided that the following conditions 39 * are met: 40 * 1. Redistributions of source code must retain the above copyright 41 * notice, this list of conditions and the following disclaimer. 42 * 2. Redistributions in binary form must reproduce the above copyright 43 * notice, this list of conditions and the following disclaimer in the 44 * documentation and/or other materials provided with the distribution. 45 * 4. Neither the name of the University nor the names of its contributors 46 * may be used to endorse or promote products derived from this software 47 * without specific prior written permission. 48 * 49 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 50 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 51 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 52 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 53 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 54 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 55 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 56 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 57 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 58 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 59 * SUCH DAMAGE. 60 * 61 * @(#)ip_icmp.c 8.2 (Berkeley) 1/4/94 62 */ 63 64#include "opt_inet.h" 65#include "opt_inet6.h" 66#include "opt_ipsec.h" 67 68#include <sys/param.h> 69#include <sys/domain.h> 70#include <sys/kernel.h> 71#include <sys/lock.h> 72#include <sys/malloc.h> 73#include <sys/mbuf.h> 74#include <sys/protosw.h> 75#include <sys/signalvar.h> 76#include <sys/socket.h> 77#include <sys/socketvar.h> 78#include <sys/sx.h> 79#include <sys/syslog.h> 80#include <sys/systm.h> 81#include <sys/time.h> 82 83#include <net/if.h> 84#include <net/if_dl.h> 85#include <net/if_types.h> 86#include <net/route.h> 87 88#include <netinet/in.h> 89#include <netinet/in_pcb.h> 90#include <netinet/in_var.h> 91#include <netinet/ip6.h> 92#include <netinet/icmp6.h> 93#include <netinet/tcp_var.h> 94#include <netinet6/in6_ifattach.h> 95#include <netinet6/in6_pcb.h> 96#include <netinet6/ip6protosw.h> 97#include <netinet6/ip6_var.h> 98#include <netinet6/scope6_var.h> 99#include <netinet6/mld6_var.h> 100#include <netinet6/nd6.h> 101 102#ifdef IPSEC 103#include <netinet6/ipsec.h> 104#include <netkey/key.h> 105#endif 106 107#ifdef FAST_IPSEC 108#include <netipsec/ipsec.h> 109#include <netipsec/key.h> 110#endif 111 112#include <net/net_osdep.h> 113 114extern struct domain inet6domain; 115 116struct icmp6stat icmp6stat; 117 118extern struct inpcbinfo ripcbinfo; 119extern struct inpcbhead ripcb; 120extern int icmp6errppslim; 121static int icmp6errpps_count = 0; 122static struct timeval icmp6errppslim_last; 123extern int icmp6_nodeinfo; 124 125static void icmp6_errcount __P((struct icmp6errstat *, int, int)); 126static int icmp6_rip6_input __P((struct mbuf **, int)); 127static int icmp6_ratelimit __P((const struct in6_addr *, const int, const int)); 128static const char *icmp6_redirect_diag __P((struct in6_addr *, 129 struct in6_addr *, struct in6_addr *)); 130static struct mbuf *ni6_input __P((struct mbuf *, int)); 131static struct mbuf *ni6_nametodns __P((const char *, int, int)); 132static int ni6_dnsmatch __P((const char *, int, const char *, int)); 133static int ni6_addrs __P((struct icmp6_nodeinfo *, struct mbuf *, 134 struct ifnet **, struct in6_addr *)); 135static int ni6_store_addrs __P((struct icmp6_nodeinfo *, struct icmp6_nodeinfo *, 136 struct ifnet *, int)); 137static int icmp6_notify_error __P((struct mbuf **, int, int, int)); 138 139#ifdef COMPAT_RFC1885 140static struct route_in6 icmp6_reflect_rt; 141#endif 142 143 144void 145icmp6_init() 146{ 147 mld6_init(); 148} 149 150static void 151icmp6_errcount(stat, type, code) 152 struct icmp6errstat *stat; 153 int type, code; 154{ 155 switch (type) { 156 case ICMP6_DST_UNREACH: 157 switch (code) { 158 case ICMP6_DST_UNREACH_NOROUTE: 159 stat->icp6errs_dst_unreach_noroute++; 160 return; 161 case ICMP6_DST_UNREACH_ADMIN: 162 stat->icp6errs_dst_unreach_admin++; 163 return; 164 case ICMP6_DST_UNREACH_BEYONDSCOPE: 165 stat->icp6errs_dst_unreach_beyondscope++; 166 return; 167 case ICMP6_DST_UNREACH_ADDR: 168 stat->icp6errs_dst_unreach_addr++; 169 return; 170 case ICMP6_DST_UNREACH_NOPORT: 171 stat->icp6errs_dst_unreach_noport++; 172 return; 173 } 174 break; 175 case ICMP6_PACKET_TOO_BIG: 176 stat->icp6errs_packet_too_big++; 177 return; 178 case ICMP6_TIME_EXCEEDED: 179 switch (code) { 180 case ICMP6_TIME_EXCEED_TRANSIT: 181 stat->icp6errs_time_exceed_transit++; 182 return; 183 case ICMP6_TIME_EXCEED_REASSEMBLY: 184 stat->icp6errs_time_exceed_reassembly++; 185 return; 186 } 187 break; 188 case ICMP6_PARAM_PROB: 189 switch (code) { 190 case ICMP6_PARAMPROB_HEADER: 191 stat->icp6errs_paramprob_header++; 192 return; 193 case ICMP6_PARAMPROB_NEXTHEADER: 194 stat->icp6errs_paramprob_nextheader++; 195 return; 196 case ICMP6_PARAMPROB_OPTION: 197 stat->icp6errs_paramprob_option++; 198 return; 199 } 200 break; 201 case ND_REDIRECT: 202 stat->icp6errs_redirect++; 203 return; 204 } 205 stat->icp6errs_unknown++; 206} 207 208/* 209 * A wrapper function for icmp6_error() necessary when the erroneous packet 210 * may not contain enough scope zone information. 211 */ 212void 213icmp6_error2(m, type, code, param, ifp) 214 struct mbuf *m; 215 int type, code, param; 216 struct ifnet *ifp; 217{ 218 struct ip6_hdr *ip6; 219 220 if (ifp == NULL) 221 return; 222 223#ifndef PULLDOWN_TEST 224 IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), ); 225#else 226 if (m->m_len < sizeof(struct ip6_hdr)) { 227 m = m_pullup(m, sizeof(struct ip6_hdr)); 228 if (m == NULL) 229 return; 230 } 231#endif 232 233 ip6 = mtod(m, struct ip6_hdr *); 234 235 if (in6_setscope(&ip6->ip6_src, ifp, NULL) != 0) 236 return; 237 if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0) 238 return; 239 240 icmp6_error(m, type, code, param); 241} 242 243/* 244 * Generate an error packet of type error in response to bad IP6 packet. 245 */ 246void 247icmp6_error(m, type, code, param) 248 struct mbuf *m; 249 int type, code, param; 250{ 251 struct ip6_hdr *oip6, *nip6; 252 struct icmp6_hdr *icmp6; 253 u_int preplen; 254 int off; 255 int nxt; 256 257 icmp6stat.icp6s_error++; 258 259 /* count per-type-code statistics */ 260 icmp6_errcount(&icmp6stat.icp6s_outerrhist, type, code); 261 262#ifdef M_DECRYPTED /*not openbsd*/ 263 if (m->m_flags & M_DECRYPTED) { 264 icmp6stat.icp6s_canterror++; 265 goto freeit; 266 } 267#endif 268 269#ifndef PULLDOWN_TEST 270 IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), ); 271#else 272 if (m->m_len < sizeof(struct ip6_hdr)) { 273 m = m_pullup(m, sizeof(struct ip6_hdr)); 274 if (m == NULL) 275 return; 276 } 277#endif 278 oip6 = mtod(m, struct ip6_hdr *); 279 280 /* 281 * If the destination address of the erroneous packet is a multicast 282 * address, or the packet was sent using link-layer multicast, 283 * we should basically suppress sending an error (RFC 2463, Section 284 * 2.4). 285 * We have two exceptions (the item e.2 in that section): 286 * - the Pakcet Too Big message can be sent for path MTU discovery. 287 * - the Parameter Problem Message that can be allowed an icmp6 error 288 * in the option type field. This check has been done in 289 * ip6_unknown_opt(), so we can just check the type and code. 290 */ 291 if ((m->m_flags & (M_BCAST|M_MCAST) || 292 IN6_IS_ADDR_MULTICAST(&oip6->ip6_dst)) && 293 (type != ICMP6_PACKET_TOO_BIG && 294 (type != ICMP6_PARAM_PROB || 295 code != ICMP6_PARAMPROB_OPTION))) 296 goto freeit; 297 298 /* 299 * RFC 2463, 2.4 (e.5): source address check. 300 * XXX: the case of anycast source? 301 */ 302 if (IN6_IS_ADDR_UNSPECIFIED(&oip6->ip6_src) || 303 IN6_IS_ADDR_MULTICAST(&oip6->ip6_src)) 304 goto freeit; 305 306 /* 307 * If we are about to send ICMPv6 against ICMPv6 error/redirect, 308 * don't do it. 309 */ 310 nxt = -1; 311 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); 312 if (off >= 0 && nxt == IPPROTO_ICMPV6) { 313 struct icmp6_hdr *icp; 314 315#ifndef PULLDOWN_TEST 316 IP6_EXTHDR_CHECK(m, 0, off + sizeof(struct icmp6_hdr), ); 317 icp = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 318#else 319 IP6_EXTHDR_GET(icp, struct icmp6_hdr *, m, off, 320 sizeof(*icp)); 321 if (icp == NULL) { 322 icmp6stat.icp6s_tooshort++; 323 return; 324 } 325#endif 326 if (icp->icmp6_type < ICMP6_ECHO_REQUEST || 327 icp->icmp6_type == ND_REDIRECT) { 328 /* 329 * ICMPv6 error 330 * Special case: for redirect (which is 331 * informational) we must not send icmp6 error. 332 */ 333 icmp6stat.icp6s_canterror++; 334 goto freeit; 335 } else { 336 /* ICMPv6 informational - send the error */ 337 } 338 } else { 339 /* non-ICMPv6 - send the error */ 340 } 341 342 oip6 = mtod(m, struct ip6_hdr *); /* adjust pointer */ 343 344 /* Finally, do rate limitation check. */ 345 if (icmp6_ratelimit(&oip6->ip6_src, type, code)) { 346 icmp6stat.icp6s_toofreq++; 347 goto freeit; 348 } 349 350 /* 351 * OK, ICMP6 can be generated. 352 */ 353 354 if (m->m_pkthdr.len >= ICMPV6_PLD_MAXLEN) 355 m_adj(m, ICMPV6_PLD_MAXLEN - m->m_pkthdr.len); 356 357 preplen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 358 M_PREPEND(m, preplen, M_DONTWAIT); 359 if (m && m->m_len < preplen) 360 m = m_pullup(m, preplen); 361 if (m == NULL) { 362 nd6log((LOG_DEBUG, "ENOBUFS in icmp6_error %d\n", __LINE__)); 363 return; 364 } 365 366 nip6 = mtod(m, struct ip6_hdr *); 367 nip6->ip6_src = oip6->ip6_src; 368 nip6->ip6_dst = oip6->ip6_dst; 369 370 in6_clearscope(&oip6->ip6_src); 371 in6_clearscope(&oip6->ip6_dst); 372 373 icmp6 = (struct icmp6_hdr *)(nip6 + 1); 374 icmp6->icmp6_type = type; 375 icmp6->icmp6_code = code; 376 icmp6->icmp6_pptr = htonl((u_int32_t)param); 377 378 /* 379 * icmp6_reflect() is designed to be in the input path. 380 * icmp6_error() can be called from both input and outut path, 381 * and if we are in output path rcvif could contain bogus value. 382 * clear m->m_pkthdr.rcvif for safety, we should have enough scope 383 * information in ip header (nip6). 384 */ 385 m->m_pkthdr.rcvif = NULL; 386 387 icmp6stat.icp6s_outhist[type]++; 388 icmp6_reflect(m, sizeof(struct ip6_hdr)); /* header order: IPv6 - ICMPv6 */ 389 390 return; 391 392 freeit: 393 /* 394 * If we can't tell wheter or not we can generate ICMP6, free it. 395 */ 396 m_freem(m); 397} 398 399/* 400 * Process a received ICMP6 message. 401 */ 402int 403icmp6_input(mp, offp, proto) 404 struct mbuf **mp; 405 int *offp, proto; 406{ 407 struct mbuf *m = *mp, *n; 408 struct ip6_hdr *ip6, *nip6; 409 struct icmp6_hdr *icmp6, *nicmp6; 410 int off = *offp; 411 int icmp6len = m->m_pkthdr.len - *offp; 412 int code, sum, noff; 413 414#ifndef PULLDOWN_TEST 415 IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_hdr), IPPROTO_DONE); 416 /* m might change if M_LOOP. So, call mtod after this */ 417#endif 418 419 /* 420 * Locate icmp6 structure in mbuf, and check 421 * that not corrupted and of at least minimum length 422 */ 423 424 ip6 = mtod(m, struct ip6_hdr *); 425 if (icmp6len < sizeof(struct icmp6_hdr)) { 426 icmp6stat.icp6s_tooshort++; 427 goto freeit; 428 } 429 430 /* 431 * calculate the checksum 432 */ 433#ifndef PULLDOWN_TEST 434 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off); 435#else 436 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 437 if (icmp6 == NULL) { 438 icmp6stat.icp6s_tooshort++; 439 return IPPROTO_DONE; 440 } 441#endif 442 code = icmp6->icmp6_code; 443 444 if ((sum = in6_cksum(m, IPPROTO_ICMPV6, off, icmp6len)) != 0) { 445 nd6log((LOG_ERR, 446 "ICMP6 checksum error(%d|%x) %s\n", 447 icmp6->icmp6_type, sum, ip6_sprintf(&ip6->ip6_src))); 448 icmp6stat.icp6s_checksum++; 449 goto freeit; 450 } 451 452 if (faithprefix_p != NULL && (*faithprefix_p)(&ip6->ip6_dst)) { 453 /* 454 * Deliver very specific ICMP6 type only. 455 * This is important to deilver TOOBIG. Otherwise PMTUD 456 * will not work. 457 */ 458 switch (icmp6->icmp6_type) { 459 case ICMP6_DST_UNREACH: 460 case ICMP6_PACKET_TOO_BIG: 461 case ICMP6_TIME_EXCEEDED: 462 break; 463 default: 464 goto freeit; 465 } 466 } 467 468 icmp6stat.icp6s_inhist[icmp6->icmp6_type]++; 469 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_msg); 470 if (icmp6->icmp6_type < ICMP6_INFOMSG_MASK) 471 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_error); 472 473 switch (icmp6->icmp6_type) { 474 case ICMP6_DST_UNREACH: 475 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_dstunreach); 476 switch (code) { 477 case ICMP6_DST_UNREACH_NOROUTE: 478 code = PRC_UNREACH_NET; 479 break; 480 case ICMP6_DST_UNREACH_ADMIN: 481 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_adminprohib); 482 code = PRC_UNREACH_PROTOCOL; /* is this a good code? */ 483 break; 484 case ICMP6_DST_UNREACH_ADDR: 485 code = PRC_HOSTDEAD; 486 break; 487#ifdef COMPAT_RFC1885 488 case ICMP6_DST_UNREACH_NOTNEIGHBOR: 489 code = PRC_UNREACH_SRCFAIL; 490 break; 491#else 492 case ICMP6_DST_UNREACH_BEYONDSCOPE: 493 /* I mean "source address was incorrect." */ 494 code = PRC_PARAMPROB; 495 break; 496#endif 497 case ICMP6_DST_UNREACH_NOPORT: 498 code = PRC_UNREACH_PORT; 499 break; 500 default: 501 goto badcode; 502 } 503 goto deliver; 504 break; 505 506 case ICMP6_PACKET_TOO_BIG: 507 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_pkttoobig); 508 509 /* validation is made in icmp6_mtudisc_update */ 510 511 code = PRC_MSGSIZE; 512 513 /* 514 * Updating the path MTU will be done after examining 515 * intermediate extension headers. 516 */ 517 goto deliver; 518 break; 519 520 case ICMP6_TIME_EXCEEDED: 521 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_timeexceed); 522 switch (code) { 523 case ICMP6_TIME_EXCEED_TRANSIT: 524 case ICMP6_TIME_EXCEED_REASSEMBLY: 525 code += PRC_TIMXCEED_INTRANS; 526 break; 527 default: 528 goto badcode; 529 } 530 goto deliver; 531 break; 532 533 case ICMP6_PARAM_PROB: 534 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_paramprob); 535 switch (code) { 536 case ICMP6_PARAMPROB_NEXTHEADER: 537 code = PRC_UNREACH_PROTOCOL; 538 break; 539 case ICMP6_PARAMPROB_HEADER: 540 case ICMP6_PARAMPROB_OPTION: 541 code = PRC_PARAMPROB; 542 break; 543 default: 544 goto badcode; 545 } 546 goto deliver; 547 break; 548 549 case ICMP6_ECHO_REQUEST: 550 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echo); 551 if (code != 0) 552 goto badcode; 553 if ((n = m_copy(m, 0, M_COPYALL)) == NULL) { 554 /* Give up remote */ 555 break; 556 } 557 if ((n->m_flags & M_EXT) != 0 558 || n->m_len < off + sizeof(struct icmp6_hdr)) { 559 struct mbuf *n0 = n; 560 const int maxlen = sizeof(*nip6) + sizeof(*nicmp6); 561 int n0len; 562 563 MGETHDR(n, M_DONTWAIT, n0->m_type); 564 n0len = n0->m_pkthdr.len; /* save for use below */ 565 if (n) 566 M_MOVE_PKTHDR(n, n0); 567 if (n && maxlen >= MHLEN) { 568 MCLGET(n, M_DONTWAIT); 569 if ((n->m_flags & M_EXT) == 0) { 570 m_free(n); 571 n = NULL; 572 } 573 } 574 if (n == NULL) { 575 /* Give up remote */ 576 m_freem(n0); 577 break; 578 } 579 /* 580 * Copy IPv6 and ICMPv6 only. 581 */ 582 nip6 = mtod(n, struct ip6_hdr *); 583 bcopy(ip6, nip6, sizeof(struct ip6_hdr)); 584 nicmp6 = (struct icmp6_hdr *)(nip6 + 1); 585 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr)); 586 noff = sizeof(struct ip6_hdr); 587 /* new mbuf contains only ipv6+icmpv6 headers */ 588 n->m_len = noff + sizeof(struct icmp6_hdr); 589 /* 590 * Adjust mbuf. ip6_plen will be adjusted in 591 * ip6_output(). 592 */ 593 m_adj(n0, off + sizeof(struct icmp6_hdr)); 594 /* recalculate complete packet size */ 595 n->m_pkthdr.len = n0len + (noff - off); 596 n->m_next = n0; 597 } else { 598 nip6 = mtod(n, struct ip6_hdr *); 599 nicmp6 = (struct icmp6_hdr *)((caddr_t)nip6 + off); 600 noff = off; 601 } 602 nicmp6->icmp6_type = ICMP6_ECHO_REPLY; 603 nicmp6->icmp6_code = 0; 604 if (n) { 605 icmp6stat.icp6s_reflect++; 606 icmp6stat.icp6s_outhist[ICMP6_ECHO_REPLY]++; 607 icmp6_reflect(n, noff); 608 } 609 break; 610 611 case ICMP6_ECHO_REPLY: 612 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echoreply); 613 if (code != 0) 614 goto badcode; 615 break; 616 617 case MLD_LISTENER_QUERY: 618 case MLD_LISTENER_REPORT: 619 if (icmp6len < sizeof(struct mld_hdr)) 620 goto badlen; 621 if (icmp6->icmp6_type == MLD_LISTENER_QUERY) /* XXX: ugly... */ 622 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldquery); 623 else 624 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldreport); 625 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 626 /* give up local */ 627 mld6_input(m, off); 628 m = NULL; 629 goto freeit; 630 } 631 mld6_input(n, off); 632 /* m stays. */ 633 break; 634 635 case MLD_LISTENER_DONE: 636 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mlddone); 637 if (icmp6len < sizeof(struct mld_hdr)) /* necessary? */ 638 goto badlen; 639 break; /* nothing to be done in kernel */ 640 641 case MLD_MTRACE_RESP: 642 case MLD_MTRACE: 643 /* XXX: these two are experimental. not officially defined. */ 644 /* XXX: per-interface statistics? */ 645 break; /* just pass it to applications */ 646 647 case ICMP6_WRUREQUEST: /* ICMP6_FQDN_QUERY */ 648 { 649 enum { WRU, FQDN } mode; 650 651 if (!icmp6_nodeinfo) 652 break; 653 654 if (icmp6len == sizeof(struct icmp6_hdr) + 4) 655 mode = WRU; 656 else if (icmp6len >= sizeof(struct icmp6_nodeinfo)) 657 mode = FQDN; 658 else 659 goto badlen; 660 661#define hostnamelen strlen(hostname) 662 if (mode == FQDN) { 663#ifndef PULLDOWN_TEST 664 IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_nodeinfo), 665 IPPROTO_DONE); 666#endif 667 n = m_copy(m, 0, M_COPYALL); 668 if (n) 669 n = ni6_input(n, off); 670 /* XXX meaningless if n == NULL */ 671 noff = sizeof(struct ip6_hdr); 672 } else { 673 u_char *p; 674 int maxlen, maxhlen; 675 676 if ((icmp6_nodeinfo & 5) != 5) 677 break; 678 679 if (code != 0) 680 goto badcode; 681 maxlen = sizeof(*nip6) + sizeof(*nicmp6) + 4; 682 if (maxlen >= MCLBYTES) { 683 /* Give up remote */ 684 break; 685 } 686 MGETHDR(n, M_DONTWAIT, m->m_type); 687 if (n && maxlen > MHLEN) { 688 MCLGET(n, M_DONTWAIT); 689 if ((n->m_flags & M_EXT) == 0) { 690 m_free(n); 691 n = NULL; 692 } 693 } 694 if (!m_dup_pkthdr(n, m, M_DONTWAIT)) { 695 /* 696 * Previous code did a blind M_COPY_PKTHDR 697 * and said "just for rcvif". If true, then 698 * we could tolerate the dup failing (due to 699 * the deep copy of the tag chain). For now 700 * be conservative and just fail. 701 */ 702 m_free(n); 703 n = NULL; 704 } 705 if (n == NULL) { 706 /* Give up remote */ 707 break; 708 } 709 n->m_pkthdr.rcvif = NULL; 710 n->m_len = 0; 711 maxhlen = M_TRAILINGSPACE(n) - maxlen; 712 if (maxhlen > hostnamelen) 713 maxhlen = hostnamelen; 714 /* 715 * Copy IPv6 and ICMPv6 only. 716 */ 717 nip6 = mtod(n, struct ip6_hdr *); 718 bcopy(ip6, nip6, sizeof(struct ip6_hdr)); 719 nicmp6 = (struct icmp6_hdr *)(nip6 + 1); 720 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr)); 721 p = (u_char *)(nicmp6 + 1); 722 bzero(p, 4); 723 bcopy(hostname, p + 4, maxhlen); /* meaningless TTL */ 724 noff = sizeof(struct ip6_hdr); 725 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) + 726 sizeof(struct icmp6_hdr) + 4 + maxhlen; 727 nicmp6->icmp6_type = ICMP6_WRUREPLY; 728 nicmp6->icmp6_code = 0; 729 } 730#undef hostnamelen 731 if (n) { 732 icmp6stat.icp6s_reflect++; 733 icmp6stat.icp6s_outhist[ICMP6_WRUREPLY]++; 734 icmp6_reflect(n, noff); 735 } 736 break; 737 } 738 739 case ICMP6_WRUREPLY: 740 if (code != 0) 741 goto badcode; 742 break; 743 744 case ND_ROUTER_SOLICIT: 745 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routersolicit); 746 if (code != 0) 747 goto badcode; 748 if (icmp6len < sizeof(struct nd_router_solicit)) 749 goto badlen; 750 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 751 /* give up local */ 752 nd6_rs_input(m, off, icmp6len); 753 m = NULL; 754 goto freeit; 755 } 756 nd6_rs_input(n, off, icmp6len); 757 /* m stays. */ 758 break; 759 760 case ND_ROUTER_ADVERT: 761 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routeradvert); 762 if (code != 0) 763 goto badcode; 764 if (icmp6len < sizeof(struct nd_router_advert)) 765 goto badlen; 766 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 767 /* give up local */ 768 nd6_ra_input(m, off, icmp6len); 769 m = NULL; 770 goto freeit; 771 } 772 nd6_ra_input(n, off, icmp6len); 773 /* m stays. */ 774 break; 775 776 case ND_NEIGHBOR_SOLICIT: 777 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighborsolicit); 778 if (code != 0) 779 goto badcode; 780 if (icmp6len < sizeof(struct nd_neighbor_solicit)) 781 goto badlen; 782 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 783 /* give up local */ 784 nd6_ns_input(m, off, icmp6len); 785 m = NULL; 786 goto freeit; 787 } 788 nd6_ns_input(n, off, icmp6len); 789 /* m stays. */ 790 break; 791 792 case ND_NEIGHBOR_ADVERT: 793 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighboradvert); 794 if (code != 0) 795 goto badcode; 796 if (icmp6len < sizeof(struct nd_neighbor_advert)) 797 goto badlen; 798 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 799 /* give up local */ 800 nd6_na_input(m, off, icmp6len); 801 m = NULL; 802 goto freeit; 803 } 804 nd6_na_input(n, off, icmp6len); 805 /* m stays. */ 806 break; 807 808 case ND_REDIRECT: 809 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_redirect); 810 if (code != 0) 811 goto badcode; 812 if (icmp6len < sizeof(struct nd_redirect)) 813 goto badlen; 814 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 815 /* give up local */ 816 icmp6_redirect_input(m, off); 817 m = NULL; 818 goto freeit; 819 } 820 icmp6_redirect_input(n, off); 821 /* m stays. */ 822 break; 823 824 case ICMP6_ROUTER_RENUMBERING: 825 if (code != ICMP6_ROUTER_RENUMBERING_COMMAND && 826 code != ICMP6_ROUTER_RENUMBERING_RESULT) 827 goto badcode; 828 if (icmp6len < sizeof(struct icmp6_router_renum)) 829 goto badlen; 830 break; 831 832 default: 833 nd6log((LOG_DEBUG, 834 "icmp6_input: unknown type %d(src=%s, dst=%s, ifid=%d)\n", 835 icmp6->icmp6_type, ip6_sprintf(&ip6->ip6_src), 836 ip6_sprintf(&ip6->ip6_dst), 837 m->m_pkthdr.rcvif ? m->m_pkthdr.rcvif->if_index : 0)); 838 if (icmp6->icmp6_type < ICMP6_ECHO_REQUEST) { 839 /* ICMPv6 error: MUST deliver it by spec... */ 840 code = PRC_NCMDS; 841 /* deliver */ 842 } else { 843 /* ICMPv6 informational: MUST not deliver */ 844 break; 845 } 846 deliver: 847 if (icmp6_notify_error(&m, off, icmp6len, code)) { 848 /* In this case, m should've been freed. */ 849 return (IPPROTO_DONE); 850 } 851 break; 852 853 badcode: 854 icmp6stat.icp6s_badcode++; 855 break; 856 857 badlen: 858 icmp6stat.icp6s_badlen++; 859 break; 860 } 861 862 /* deliver the packet to appropriate sockets */ 863 icmp6_rip6_input(&m, *offp); 864 865 return IPPROTO_DONE; 866 867 freeit: 868 m_freem(m); 869 return IPPROTO_DONE; 870} 871 872static int 873icmp6_notify_error(mp, off, icmp6len, code) 874 struct mbuf **mp; 875 int off, icmp6len, code; 876{ 877 struct mbuf *m = *mp; 878 struct icmp6_hdr *icmp6; 879 struct ip6_hdr *eip6; 880 u_int32_t notifymtu; 881 struct sockaddr_in6 icmp6src, icmp6dst; 882 883 if (icmp6len < sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr)) { 884 icmp6stat.icp6s_tooshort++; 885 goto freeit; 886 } 887#ifndef PULLDOWN_TEST 888 IP6_EXTHDR_CHECK(m, off, 889 sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr), -1); 890 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 891#else 892 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, 893 sizeof(*icmp6) + sizeof(struct ip6_hdr)); 894 if (icmp6 == NULL) { 895 icmp6stat.icp6s_tooshort++; 896 return (-1); 897 } 898#endif 899 eip6 = (struct ip6_hdr *)(icmp6 + 1); 900 901 /* Detect the upper level protocol */ 902 { 903 void (*ctlfunc) __P((int, struct sockaddr *, void *)); 904 u_int8_t nxt = eip6->ip6_nxt; 905 int eoff = off + sizeof(struct icmp6_hdr) + 906 sizeof(struct ip6_hdr); 907 struct ip6ctlparam ip6cp; 908 struct in6_addr *finaldst = NULL; 909 int icmp6type = icmp6->icmp6_type; 910 struct ip6_frag *fh; 911 struct ip6_rthdr *rth; 912 struct ip6_rthdr0 *rth0; 913 int rthlen; 914 915 while (1) { /* XXX: should avoid infinite loop explicitly? */ 916 struct ip6_ext *eh; 917 918 switch (nxt) { 919 case IPPROTO_HOPOPTS: 920 case IPPROTO_DSTOPTS: 921 case IPPROTO_AH: 922#ifndef PULLDOWN_TEST 923 IP6_EXTHDR_CHECK(m, 0, 924 eoff + sizeof(struct ip6_ext), -1); 925 eh = (struct ip6_ext *)(mtod(m, caddr_t) + eoff); 926#else 927 IP6_EXTHDR_GET(eh, struct ip6_ext *, m, 928 eoff, sizeof(*eh)); 929 if (eh == NULL) { 930 icmp6stat.icp6s_tooshort++; 931 return (-1); 932 } 933#endif 934 935 if (nxt == IPPROTO_AH) 936 eoff += (eh->ip6e_len + 2) << 2; 937 else 938 eoff += (eh->ip6e_len + 1) << 3; 939 nxt = eh->ip6e_nxt; 940 break; 941 case IPPROTO_ROUTING: 942 /* 943 * When the erroneous packet contains a 944 * routing header, we should examine the 945 * header to determine the final destination. 946 * Otherwise, we can't properly update 947 * information that depends on the final 948 * destination (e.g. path MTU). 949 */ 950#ifndef PULLDOWN_TEST 951 IP6_EXTHDR_CHECK(m, 0, eoff + sizeof(*rth), -1); 952 rth = (struct ip6_rthdr *) 953 (mtod(m, caddr_t) + eoff); 954#else 955 IP6_EXTHDR_GET(rth, struct ip6_rthdr *, m, 956 eoff, sizeof(*rth)); 957 if (rth == NULL) { 958 icmp6stat.icp6s_tooshort++; 959 return (-1); 960 } 961#endif 962 rthlen = (rth->ip6r_len + 1) << 3; 963 /* 964 * XXX: currently there is no 965 * officially defined type other 966 * than type-0. 967 * Note that if the segment left field 968 * is 0, all intermediate hops must 969 * have been passed. 970 */ 971 if (rth->ip6r_segleft && 972 rth->ip6r_type == IPV6_RTHDR_TYPE_0) { 973 int hops; 974 975#ifndef PULLDOWN_TEST 976 IP6_EXTHDR_CHECK(m, 0, eoff + rthlen, -1); 977 rth0 = (struct ip6_rthdr0 *) 978 (mtod(m, caddr_t) + eoff); 979#else 980 IP6_EXTHDR_GET(rth0, 981 struct ip6_rthdr0 *, m, 982 eoff, rthlen); 983 if (rth0 == NULL) { 984 icmp6stat.icp6s_tooshort++; 985 return (-1); 986 } 987#endif 988 /* just ignore a bogus header */ 989 if ((rth0->ip6r0_len % 2) == 0 && 990 (hops = rth0->ip6r0_len/2)) 991 finaldst = (struct in6_addr *)(rth0 + 1) + (hops - 1); 992 } 993 eoff += rthlen; 994 nxt = rth->ip6r_nxt; 995 break; 996 case IPPROTO_FRAGMENT: 997#ifndef PULLDOWN_TEST 998 IP6_EXTHDR_CHECK(m, 0, eoff + 999 sizeof(struct ip6_frag), -1); 1000 fh = (struct ip6_frag *)(mtod(m, caddr_t) + 1001 eoff); 1002#else 1003 IP6_EXTHDR_GET(fh, struct ip6_frag *, m, 1004 eoff, sizeof(*fh)); 1005 if (fh == NULL) { 1006 icmp6stat.icp6s_tooshort++; 1007 return (-1); 1008 } 1009#endif 1010 /* 1011 * Data after a fragment header is meaningless 1012 * unless it is the first fragment, but 1013 * we'll go to the notify label for path MTU 1014 * discovery. 1015 */ 1016 if (fh->ip6f_offlg & IP6F_OFF_MASK) 1017 goto notify; 1018 1019 eoff += sizeof(struct ip6_frag); 1020 nxt = fh->ip6f_nxt; 1021 break; 1022 default: 1023 /* 1024 * This case includes ESP and the No Next 1025 * Header. In such cases going to the notify 1026 * label does not have any meaning 1027 * (i.e. ctlfunc will be NULL), but we go 1028 * anyway since we might have to update 1029 * path MTU information. 1030 */ 1031 goto notify; 1032 } 1033 } 1034 notify: 1035#ifndef PULLDOWN_TEST 1036 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 1037#else 1038 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, 1039 sizeof(*icmp6) + sizeof(struct ip6_hdr)); 1040 if (icmp6 == NULL) { 1041 icmp6stat.icp6s_tooshort++; 1042 return (-1); 1043 } 1044#endif 1045 1046 /* 1047 * retrieve parameters from the inner IPv6 header, and convert 1048 * them into sockaddr structures. 1049 * XXX: there is no guarantee that the source or destination 1050 * addresses of the inner packet are in the same scope as 1051 * the addresses of the icmp packet. But there is no other 1052 * way to determine the zone. 1053 */ 1054 eip6 = (struct ip6_hdr *)(icmp6 + 1); 1055 1056 bzero(&icmp6dst, sizeof(icmp6dst)); 1057 icmp6dst.sin6_len = sizeof(struct sockaddr_in6); 1058 icmp6dst.sin6_family = AF_INET6; 1059 if (finaldst == NULL) 1060 icmp6dst.sin6_addr = eip6->ip6_dst; 1061 else 1062 icmp6dst.sin6_addr = *finaldst; 1063 if (in6_setscope(&icmp6dst.sin6_addr, m->m_pkthdr.rcvif, NULL)) 1064 goto freeit; 1065 bzero(&icmp6src, sizeof(icmp6src)); 1066 icmp6src.sin6_len = sizeof(struct sockaddr_in6); 1067 icmp6src.sin6_family = AF_INET6; 1068 icmp6src.sin6_addr = eip6->ip6_src; 1069 if (in6_setscope(&icmp6src.sin6_addr, m->m_pkthdr.rcvif, NULL)) 1070 goto freeit; 1071 icmp6src.sin6_flowinfo = 1072 (eip6->ip6_flow & IPV6_FLOWLABEL_MASK); 1073 1074 if (finaldst == NULL) 1075 finaldst = &eip6->ip6_dst; 1076 ip6cp.ip6c_m = m; 1077 ip6cp.ip6c_icmp6 = icmp6; 1078 ip6cp.ip6c_ip6 = (struct ip6_hdr *)(icmp6 + 1); 1079 ip6cp.ip6c_off = eoff; 1080 ip6cp.ip6c_finaldst = finaldst; 1081 ip6cp.ip6c_src = &icmp6src; 1082 ip6cp.ip6c_nxt = nxt; 1083 1084 if (icmp6type == ICMP6_PACKET_TOO_BIG) { 1085 notifymtu = ntohl(icmp6->icmp6_mtu); 1086 ip6cp.ip6c_cmdarg = (void *)¬ifymtu; 1087 icmp6_mtudisc_update(&ip6cp, 1); /*XXX*/ 1088 } 1089 1090 ctlfunc = (void (*) __P((int, struct sockaddr *, void *))) 1091 (inet6sw[ip6_protox[nxt]].pr_ctlinput); 1092 if (ctlfunc) { 1093 (void) (*ctlfunc)(code, (struct sockaddr *)&icmp6dst, 1094 &ip6cp); 1095 } 1096 } 1097 *mp = m; 1098 return (0); 1099 1100 freeit: 1101 m_freem(m); 1102 return (-1); 1103} 1104 1105void 1106icmp6_mtudisc_update(ip6cp, validated) 1107 struct ip6ctlparam *ip6cp; 1108 int validated; 1109{ 1110 struct in6_addr *dst = ip6cp->ip6c_finaldst; 1111 struct icmp6_hdr *icmp6 = ip6cp->ip6c_icmp6; 1112 struct mbuf *m = ip6cp->ip6c_m; /* will be necessary for scope issue */ 1113 u_int mtu = ntohl(icmp6->icmp6_mtu); 1114 struct in_conninfo inc; 1115 1116#if 0 1117 /* 1118 * RFC2460 section 5, last paragraph. 1119 * even though minimum link MTU for IPv6 is IPV6_MMTU, 1120 * we may see ICMPv6 too big with mtu < IPV6_MMTU 1121 * due to packet translator in the middle. 1122 * see ip6_output() and ip6_getpmtu() "alwaysfrag" case for 1123 * special handling. 1124 */ 1125 if (mtu < IPV6_MMTU) 1126 return; 1127#endif 1128 1129 /* 1130 * we reject ICMPv6 too big with abnormally small value. 1131 * XXX what is the good definition of "abnormally small"? 1132 */ 1133 if (mtu < sizeof(struct ip6_hdr) + sizeof(struct ip6_frag) + 8) 1134 return; 1135 1136 if (!validated) 1137 return; 1138 1139 bzero(&inc, sizeof(inc)); 1140 inc.inc_flags = 1; /* IPv6 */ 1141 inc.inc6_faddr = *dst; 1142 if (in6_setscope(&inc.inc6_faddr, m->m_pkthdr.rcvif, NULL)) 1143 return; 1144 1145 if (mtu < tcp_maxmtu6(&inc)) { 1146 tcp_hc_updatemtu(&inc, mtu); 1147 icmp6stat.icp6s_pmtuchg++; 1148 } 1149} 1150 1151/* 1152 * Process a Node Information Query packet, based on 1153 * draft-ietf-ipngwg-icmp-name-lookups-07. 1154 * 1155 * Spec incompatibilities: 1156 * - IPv6 Subject address handling 1157 * - IPv4 Subject address handling support missing 1158 * - Proxy reply (answer even if it's not for me) 1159 * - joins NI group address at in6_ifattach() time only, does not cope 1160 * with hostname changes by sethostname(3) 1161 */ 1162#define hostnamelen strlen(hostname) 1163static struct mbuf * 1164ni6_input(m, off) 1165 struct mbuf *m; 1166 int off; 1167{ 1168 struct icmp6_nodeinfo *ni6, *nni6; 1169 struct mbuf *n = NULL; 1170 u_int16_t qtype; 1171 int subjlen; 1172 int replylen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo); 1173 struct ni_reply_fqdn *fqdn; 1174 int addrs; /* for NI_QTYPE_NODEADDR */ 1175 struct ifnet *ifp = NULL; /* for NI_QTYPE_NODEADDR */ 1176 struct in6_addr in6_subj; /* subject address */ 1177 struct ip6_hdr *ip6; 1178 int oldfqdn = 0; /* if 1, return pascal string (03 draft) */ 1179 char *subj = NULL; 1180 struct in6_ifaddr *ia6 = NULL; 1181 1182 ip6 = mtod(m, struct ip6_hdr *); 1183#ifndef PULLDOWN_TEST 1184 ni6 = (struct icmp6_nodeinfo *)(mtod(m, caddr_t) + off); 1185#else 1186 IP6_EXTHDR_GET(ni6, struct icmp6_nodeinfo *, m, off, sizeof(*ni6)); 1187 if (ni6 == NULL) { 1188 /* m is already reclaimed */ 1189 return (NULL); 1190 } 1191#endif 1192 1193 /* 1194 * Validate IPv6 destination address. 1195 * 1196 * The Responder must discard the Query without further processing 1197 * unless it is one of the Responder's unicast or anycast addresses, or 1198 * a link-local scope multicast address which the Responder has joined. 1199 * [icmp-name-lookups-08, Section 4.] 1200 */ 1201 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 1202 if (!IN6_IS_ADDR_MC_LINKLOCAL(&ip6->ip6_dst)) 1203 goto bad; 1204 /* else it's a link-local multicast, fine */ 1205 } else { /* unicast or anycast */ 1206 if ((ia6 = ip6_getdstifaddr(m)) == NULL) 1207 goto bad; /* XXX impossible */ 1208 1209 if ((ia6->ia6_flags & IN6_IFF_TEMPORARY) && 1210 !(icmp6_nodeinfo & 4)) { 1211 nd6log((LOG_DEBUG, "ni6_input: ignore node info to " 1212 "a temporary address in %s:%d", 1213 __FILE__, __LINE__)); 1214 goto bad; 1215 } 1216 } 1217 1218 /* validate query Subject field. */ 1219 qtype = ntohs(ni6->ni_qtype); 1220 subjlen = m->m_pkthdr.len - off - sizeof(struct icmp6_nodeinfo); 1221 switch (qtype) { 1222 case NI_QTYPE_NOOP: 1223 case NI_QTYPE_SUPTYPES: 1224 /* 07 draft */ 1225 if (ni6->ni_code == ICMP6_NI_SUBJ_FQDN && subjlen == 0) 1226 break; 1227 /* FALLTHROUGH */ 1228 case NI_QTYPE_FQDN: 1229 case NI_QTYPE_NODEADDR: 1230 switch (ni6->ni_code) { 1231 case ICMP6_NI_SUBJ_IPV6: 1232#if ICMP6_NI_SUBJ_IPV6 != 0 1233 case 0: 1234#endif 1235 /* 1236 * backward compatibility - try to accept 03 draft 1237 * format, where no Subject is present. 1238 */ 1239 if (qtype == NI_QTYPE_FQDN && ni6->ni_code == 0 && 1240 subjlen == 0) { 1241 oldfqdn++; 1242 break; 1243 } 1244#if ICMP6_NI_SUBJ_IPV6 != 0 1245 if (ni6->ni_code != ICMP6_NI_SUBJ_IPV6) 1246 goto bad; 1247#endif 1248 1249 if (subjlen != sizeof(struct in6_addr)) 1250 goto bad; 1251 1252 /* 1253 * Validate Subject address. 1254 * 1255 * Not sure what exactly "address belongs to the node" 1256 * means in the spec, is it just unicast, or what? 1257 * 1258 * At this moment we consider Subject address as 1259 * "belong to the node" if the Subject address equals 1260 * to the IPv6 destination address; validation for 1261 * IPv6 destination address should have done enough 1262 * check for us. 1263 * 1264 * We do not do proxy at this moment. 1265 */ 1266 /* m_pulldown instead of copy? */ 1267 m_copydata(m, off + sizeof(struct icmp6_nodeinfo), 1268 subjlen, (caddr_t)&in6_subj); 1269 if (in6_setscope(&in6_subj, m->m_pkthdr.rcvif, NULL)) 1270 goto bad; 1271 1272 subj = (char *)&in6_subj; 1273 if (IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, &in6_subj)) 1274 break; 1275 1276 /* 1277 * XXX if we are to allow other cases, we should really 1278 * be careful about scope here. 1279 * basically, we should disallow queries toward IPv6 1280 * destination X with subject Y, 1281 * if scope(X) > scope(Y). 1282 * if we allow scope(X) > scope(Y), it will result in 1283 * information leakage across scope boundary. 1284 */ 1285 goto bad; 1286 1287 case ICMP6_NI_SUBJ_FQDN: 1288 /* 1289 * Validate Subject name with gethostname(3). 1290 * 1291 * The behavior may need some debate, since: 1292 * - we are not sure if the node has FQDN as 1293 * hostname (returned by gethostname(3)). 1294 * - the code does wildcard match for truncated names. 1295 * however, we are not sure if we want to perform 1296 * wildcard match, if gethostname(3) side has 1297 * truncated hostname. 1298 */ 1299 n = ni6_nametodns(hostname, hostnamelen, 0); 1300 if (!n || n->m_next || n->m_len == 0) 1301 goto bad; 1302 IP6_EXTHDR_GET(subj, char *, m, 1303 off + sizeof(struct icmp6_nodeinfo), subjlen); 1304 if (subj == NULL) 1305 goto bad; 1306 if (!ni6_dnsmatch(subj, subjlen, mtod(n, const char *), 1307 n->m_len)) { 1308 goto bad; 1309 } 1310 m_freem(n); 1311 n = NULL; 1312 break; 1313 1314 case ICMP6_NI_SUBJ_IPV4: /* XXX: to be implemented? */ 1315 default: 1316 goto bad; 1317 } 1318 break; 1319 } 1320 1321 /* refuse based on configuration. XXX ICMP6_NI_REFUSED? */ 1322 switch (qtype) { 1323 case NI_QTYPE_FQDN: 1324 if ((icmp6_nodeinfo & 1) == 0) 1325 goto bad; 1326 break; 1327 case NI_QTYPE_NODEADDR: 1328 if ((icmp6_nodeinfo & 2) == 0) 1329 goto bad; 1330 break; 1331 } 1332 1333 /* guess reply length */ 1334 switch (qtype) { 1335 case NI_QTYPE_NOOP: 1336 break; /* no reply data */ 1337 case NI_QTYPE_SUPTYPES: 1338 replylen += sizeof(u_int32_t); 1339 break; 1340 case NI_QTYPE_FQDN: 1341 /* XXX will append an mbuf */ 1342 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1343 break; 1344 case NI_QTYPE_NODEADDR: 1345 addrs = ni6_addrs(ni6, m, &ifp, (struct in6_addr *)subj); 1346 if ((replylen += addrs * (sizeof(struct in6_addr) + 1347 sizeof(u_int32_t))) > MCLBYTES) 1348 replylen = MCLBYTES; /* XXX: will truncate pkt later */ 1349 break; 1350 default: 1351 /* 1352 * XXX: We must return a reply with the ICMP6 code 1353 * `unknown Qtype' in this case. However we regard the case 1354 * as an FQDN query for backward compatibility. 1355 * Older versions set a random value to this field, 1356 * so it rarely varies in the defined qtypes. 1357 * But the mechanism is not reliable... 1358 * maybe we should obsolete older versions. 1359 */ 1360 qtype = NI_QTYPE_FQDN; 1361 /* XXX will append an mbuf */ 1362 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1363 oldfqdn++; 1364 break; 1365 } 1366 1367 /* allocate an mbuf to reply. */ 1368 MGETHDR(n, M_DONTWAIT, m->m_type); 1369 if (n == NULL) { 1370 m_freem(m); 1371 return (NULL); 1372 } 1373 M_MOVE_PKTHDR(n, m); /* just for recvif */ 1374 if (replylen > MHLEN) { 1375 if (replylen > MCLBYTES) { 1376 /* 1377 * XXX: should we try to allocate more? But MCLBYTES 1378 * is probably much larger than IPV6_MMTU... 1379 */ 1380 goto bad; 1381 } 1382 MCLGET(n, M_DONTWAIT); 1383 if ((n->m_flags & M_EXT) == 0) { 1384 goto bad; 1385 } 1386 } 1387 n->m_pkthdr.len = n->m_len = replylen; 1388 1389 /* copy mbuf header and IPv6 + Node Information base headers */ 1390 bcopy(mtod(m, caddr_t), mtod(n, caddr_t), sizeof(struct ip6_hdr)); 1391 nni6 = (struct icmp6_nodeinfo *)(mtod(n, struct ip6_hdr *) + 1); 1392 bcopy((caddr_t)ni6, (caddr_t)nni6, sizeof(struct icmp6_nodeinfo)); 1393 1394 /* qtype dependent procedure */ 1395 switch (qtype) { 1396 case NI_QTYPE_NOOP: 1397 nni6->ni_code = ICMP6_NI_SUCCESS; 1398 nni6->ni_flags = 0; 1399 break; 1400 case NI_QTYPE_SUPTYPES: 1401 { 1402 u_int32_t v; 1403 nni6->ni_code = ICMP6_NI_SUCCESS; 1404 nni6->ni_flags = htons(0x0000); /* raw bitmap */ 1405 /* supports NOOP, SUPTYPES, FQDN, and NODEADDR */ 1406 v = (u_int32_t)htonl(0x0000000f); 1407 bcopy(&v, nni6 + 1, sizeof(u_int32_t)); 1408 break; 1409 } 1410 case NI_QTYPE_FQDN: 1411 nni6->ni_code = ICMP6_NI_SUCCESS; 1412 fqdn = (struct ni_reply_fqdn *)(mtod(n, caddr_t) + 1413 sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo)); 1414 nni6->ni_flags = 0; /* XXX: meaningless TTL */ 1415 fqdn->ni_fqdn_ttl = 0; /* ditto. */ 1416 /* 1417 * XXX do we really have FQDN in variable "hostname"? 1418 */ 1419 n->m_next = ni6_nametodns(hostname, hostnamelen, oldfqdn); 1420 if (n->m_next == NULL) 1421 goto bad; 1422 /* XXX we assume that n->m_next is not a chain */ 1423 if (n->m_next->m_next != NULL) 1424 goto bad; 1425 n->m_pkthdr.len += n->m_next->m_len; 1426 break; 1427 case NI_QTYPE_NODEADDR: 1428 { 1429 int lenlim, copied; 1430 1431 nni6->ni_code = ICMP6_NI_SUCCESS; 1432 n->m_pkthdr.len = n->m_len = 1433 sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo); 1434 lenlim = M_TRAILINGSPACE(n); 1435 copied = ni6_store_addrs(ni6, nni6, ifp, lenlim); 1436 /* XXX: reset mbuf length */ 1437 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) + 1438 sizeof(struct icmp6_nodeinfo) + copied; 1439 break; 1440 } 1441 default: 1442 break; /* XXX impossible! */ 1443 } 1444 1445 nni6->ni_type = ICMP6_NI_REPLY; 1446 m_freem(m); 1447 return (n); 1448 1449 bad: 1450 m_freem(m); 1451 if (n) 1452 m_freem(n); 1453 return (NULL); 1454} 1455#undef hostnamelen 1456 1457/* 1458 * make a mbuf with DNS-encoded string. no compression support. 1459 * 1460 * XXX names with less than 2 dots (like "foo" or "foo.section") will be 1461 * treated as truncated name (two \0 at the end). this is a wild guess. 1462 */ 1463static struct mbuf * 1464ni6_nametodns(name, namelen, old) 1465 const char *name; 1466 int namelen; 1467 int old; /* return pascal string if non-zero */ 1468{ 1469 struct mbuf *m; 1470 char *cp, *ep; 1471 const char *p, *q; 1472 int i, len, nterm; 1473 1474 if (old) 1475 len = namelen + 1; 1476 else 1477 len = MCLBYTES; 1478 1479 /* because MAXHOSTNAMELEN is usually 256, we use cluster mbuf */ 1480 MGET(m, M_DONTWAIT, MT_DATA); 1481 if (m && len > MLEN) { 1482 MCLGET(m, M_DONTWAIT); 1483 if ((m->m_flags & M_EXT) == 0) 1484 goto fail; 1485 } 1486 if (!m) 1487 goto fail; 1488 m->m_next = NULL; 1489 1490 if (old) { 1491 m->m_len = len; 1492 *mtod(m, char *) = namelen; 1493 bcopy(name, mtod(m, char *) + 1, namelen); 1494 return m; 1495 } else { 1496 m->m_len = 0; 1497 cp = mtod(m, char *); 1498 ep = mtod(m, char *) + M_TRAILINGSPACE(m); 1499 1500 /* if not certain about my name, return empty buffer */ 1501 if (namelen == 0) 1502 return m; 1503 1504 /* 1505 * guess if it looks like shortened hostname, or FQDN. 1506 * shortened hostname needs two trailing "\0". 1507 */ 1508 i = 0; 1509 for (p = name; p < name + namelen; p++) { 1510 if (*p && *p == '.') 1511 i++; 1512 } 1513 if (i < 2) 1514 nterm = 2; 1515 else 1516 nterm = 1; 1517 1518 p = name; 1519 while (cp < ep && p < name + namelen) { 1520 i = 0; 1521 for (q = p; q < name + namelen && *q && *q != '.'; q++) 1522 i++; 1523 /* result does not fit into mbuf */ 1524 if (cp + i + 1 >= ep) 1525 goto fail; 1526 /* 1527 * DNS label length restriction, RFC1035 page 8. 1528 * "i == 0" case is included here to avoid returning 1529 * 0-length label on "foo..bar". 1530 */ 1531 if (i <= 0 || i >= 64) 1532 goto fail; 1533 *cp++ = i; 1534 bcopy(p, cp, i); 1535 cp += i; 1536 p = q; 1537 if (p < name + namelen && *p == '.') 1538 p++; 1539 } 1540 /* termination */ 1541 if (cp + nterm >= ep) 1542 goto fail; 1543 while (nterm-- > 0) 1544 *cp++ = '\0'; 1545 m->m_len = cp - mtod(m, char *); 1546 return m; 1547 } 1548 1549 panic("should not reach here"); 1550 /* NOTREACHED */ 1551 1552 fail: 1553 if (m) 1554 m_freem(m); 1555 return NULL; 1556} 1557 1558/* 1559 * check if two DNS-encoded string matches. takes care of truncated 1560 * form (with \0\0 at the end). no compression support. 1561 * XXX upper/lowercase match (see RFC2065) 1562 */ 1563static int 1564ni6_dnsmatch(a, alen, b, blen) 1565 const char *a; 1566 int alen; 1567 const char *b; 1568 int blen; 1569{ 1570 const char *a0, *b0; 1571 int l; 1572 1573 /* simplest case - need validation? */ 1574 if (alen == blen && bcmp(a, b, alen) == 0) 1575 return 1; 1576 1577 a0 = a; 1578 b0 = b; 1579 1580 /* termination is mandatory */ 1581 if (alen < 2 || blen < 2) 1582 return 0; 1583 if (a0[alen - 1] != '\0' || b0[blen - 1] != '\0') 1584 return 0; 1585 alen--; 1586 blen--; 1587 1588 while (a - a0 < alen && b - b0 < blen) { 1589 if (a - a0 + 1 > alen || b - b0 + 1 > blen) 1590 return 0; 1591 1592 if ((signed char)a[0] < 0 || (signed char)b[0] < 0) 1593 return 0; 1594 /* we don't support compression yet */ 1595 if (a[0] >= 64 || b[0] >= 64) 1596 return 0; 1597 1598 /* truncated case */ 1599 if (a[0] == 0 && a - a0 == alen - 1) 1600 return 1; 1601 if (b[0] == 0 && b - b0 == blen - 1) 1602 return 1; 1603 if (a[0] == 0 || b[0] == 0) 1604 return 0; 1605 1606 if (a[0] != b[0]) 1607 return 0; 1608 l = a[0]; 1609 if (a - a0 + 1 + l > alen || b - b0 + 1 + l > blen) 1610 return 0; 1611 if (bcmp(a + 1, b + 1, l) != 0) 1612 return 0; 1613 1614 a += 1 + l; 1615 b += 1 + l; 1616 } 1617 1618 if (a - a0 == alen && b - b0 == blen) 1619 return 1; 1620 else 1621 return 0; 1622} 1623 1624/* 1625 * calculate the number of addresses to be returned in the node info reply. 1626 */ 1627static int 1628ni6_addrs(ni6, m, ifpp, subj) 1629 struct icmp6_nodeinfo *ni6; 1630 struct mbuf *m; 1631 struct ifnet **ifpp; 1632 struct in6_addr *subj; 1633{ 1634 struct ifnet *ifp; 1635 struct in6_ifaddr *ifa6; 1636 struct ifaddr *ifa; 1637 int addrs = 0, addrsofif, iffound = 0; 1638 int niflags = ni6->ni_flags; 1639 1640 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0) { 1641 switch (ni6->ni_code) { 1642 case ICMP6_NI_SUBJ_IPV6: 1643 if (subj == NULL) /* must be impossible... */ 1644 return (0); 1645 break; 1646 default: 1647 /* 1648 * XXX: we only support IPv6 subject address for 1649 * this Qtype. 1650 */ 1651 return (0); 1652 } 1653 } 1654 1655 IFNET_RLOCK(); 1656 for (ifp = TAILQ_FIRST(&ifnet); ifp; ifp = TAILQ_NEXT(ifp, if_list)) { 1657 addrsofif = 0; 1658 TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list) { 1659 if (ifa->ifa_addr->sa_family != AF_INET6) 1660 continue; 1661 ifa6 = (struct in6_ifaddr *)ifa; 1662 1663 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0 && 1664 IN6_ARE_ADDR_EQUAL(subj, &ifa6->ia_addr.sin6_addr)) 1665 iffound = 1; 1666 1667 /* 1668 * IPv4-mapped addresses can only be returned by a 1669 * Node Information proxy, since they represent 1670 * addresses of IPv4-only nodes, which perforce do 1671 * not implement this protocol. 1672 * [icmp-name-lookups-07, Section 5.4] 1673 * So we don't support NI_NODEADDR_FLAG_COMPAT in 1674 * this function at this moment. 1675 */ 1676 1677 /* What do we have to do about ::1? */ 1678 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1679 case IPV6_ADDR_SCOPE_LINKLOCAL: 1680 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0) 1681 continue; 1682 break; 1683 case IPV6_ADDR_SCOPE_SITELOCAL: 1684 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0) 1685 continue; 1686 break; 1687 case IPV6_ADDR_SCOPE_GLOBAL: 1688 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0) 1689 continue; 1690 break; 1691 default: 1692 continue; 1693 } 1694 1695 /* 1696 * check if anycast is okay. 1697 * XXX: just experimental. not in the spec. 1698 */ 1699 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 && 1700 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0) 1701 continue; /* we need only unicast addresses */ 1702 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 1703 (icmp6_nodeinfo & 4) == 0) { 1704 continue; 1705 } 1706 addrsofif++; /* count the address */ 1707 } 1708 if (iffound) { 1709 *ifpp = ifp; 1710 IFNET_RUNLOCK(); 1711 return (addrsofif); 1712 } 1713 1714 addrs += addrsofif; 1715 } 1716 IFNET_RUNLOCK(); 1717 1718 return (addrs); 1719} 1720 1721static int 1722ni6_store_addrs(ni6, nni6, ifp0, resid) 1723 struct icmp6_nodeinfo *ni6, *nni6; 1724 struct ifnet *ifp0; 1725 int resid; 1726{ 1727 struct ifnet *ifp = ifp0 ? ifp0 : TAILQ_FIRST(&ifnet); 1728 struct in6_ifaddr *ifa6; 1729 struct ifaddr *ifa; 1730 struct ifnet *ifp_dep = NULL; 1731 int copied = 0, allow_deprecated = 0; 1732 u_char *cp = (u_char *)(nni6 + 1); 1733 int niflags = ni6->ni_flags; 1734 u_int32_t ltime; 1735 1736 if (ifp0 == NULL && !(niflags & NI_NODEADDR_FLAG_ALL)) 1737 return (0); /* needless to copy */ 1738 1739 IFNET_RLOCK(); 1740 again: 1741 1742 for (; ifp; ifp = TAILQ_NEXT(ifp, if_list)) { 1743 for (ifa = ifp->if_addrlist.tqh_first; ifa; 1744 ifa = ifa->ifa_list.tqe_next) { 1745 if (ifa->ifa_addr->sa_family != AF_INET6) 1746 continue; 1747 ifa6 = (struct in6_ifaddr *)ifa; 1748 1749 if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) != 0 && 1750 allow_deprecated == 0) { 1751 /* 1752 * prefererred address should be put before 1753 * deprecated addresses. 1754 */ 1755 1756 /* record the interface for later search */ 1757 if (ifp_dep == NULL) 1758 ifp_dep = ifp; 1759 1760 continue; 1761 } else if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) == 0 && 1762 allow_deprecated != 0) 1763 continue; /* we now collect deprecated addrs */ 1764 1765 /* What do we have to do about ::1? */ 1766 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1767 case IPV6_ADDR_SCOPE_LINKLOCAL: 1768 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0) 1769 continue; 1770 break; 1771 case IPV6_ADDR_SCOPE_SITELOCAL: 1772 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0) 1773 continue; 1774 break; 1775 case IPV6_ADDR_SCOPE_GLOBAL: 1776 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0) 1777 continue; 1778 break; 1779 default: 1780 continue; 1781 } 1782 1783 /* 1784 * check if anycast is okay. 1785 * XXX: just experimental. not in the spec. 1786 */ 1787 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 && 1788 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0) 1789 continue; 1790 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 1791 (icmp6_nodeinfo & 4) == 0) { 1792 continue; 1793 } 1794 1795 /* now we can copy the address */ 1796 if (resid < sizeof(struct in6_addr) + 1797 sizeof(u_int32_t)) { 1798 /* 1799 * We give up much more copy. 1800 * Set the truncate flag and return. 1801 */ 1802 nni6->ni_flags |= NI_NODEADDR_FLAG_TRUNCATE; 1803 IFNET_RUNLOCK(); 1804 return (copied); 1805 } 1806 1807 /* 1808 * Set the TTL of the address. 1809 * The TTL value should be one of the following 1810 * according to the specification: 1811 * 1812 * 1. The remaining lifetime of a DHCP lease on the 1813 * address, or 1814 * 2. The remaining Valid Lifetime of a prefix from 1815 * which the address was derived through Stateless 1816 * Autoconfiguration. 1817 * 1818 * Note that we currently do not support stateful 1819 * address configuration by DHCPv6, so the former 1820 * case can't happen. 1821 */ 1822 if (ifa6->ia6_lifetime.ia6t_expire == 0) 1823 ltime = ND6_INFINITE_LIFETIME; 1824 else { 1825 if (ifa6->ia6_lifetime.ia6t_expire > 1826 time_second) 1827 ltime = htonl(ifa6->ia6_lifetime.ia6t_expire - time_second); 1828 else 1829 ltime = 0; 1830 } 1831 1832 bcopy(<ime, cp, sizeof(u_int32_t)); 1833 cp += sizeof(u_int32_t); 1834 1835 /* copy the address itself */ 1836 bcopy(&ifa6->ia_addr.sin6_addr, cp, 1837 sizeof(struct in6_addr)); 1838 in6_clearscope((struct in6_addr *)cp); /* XXX */ 1839 cp += sizeof(struct in6_addr); 1840 1841 resid -= (sizeof(struct in6_addr) + sizeof(u_int32_t)); 1842 copied += (sizeof(struct in6_addr) + sizeof(u_int32_t)); 1843 } 1844 if (ifp0) /* we need search only on the specified IF */ 1845 break; 1846 } 1847 1848 if (allow_deprecated == 0 && ifp_dep != NULL) { 1849 ifp = ifp_dep; 1850 allow_deprecated = 1; 1851 1852 goto again; 1853 } 1854 1855 IFNET_RUNLOCK(); 1856 1857 return (copied); 1858} 1859 1860/* 1861 * XXX almost dup'ed code with rip6_input. 1862 */ 1863static int 1864icmp6_rip6_input(mp, off) 1865 struct mbuf **mp; 1866 int off; 1867{ 1868 struct mbuf *m = *mp; 1869 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1870 struct in6pcb *in6p; 1871 struct in6pcb *last = NULL; 1872 struct sockaddr_in6 fromsa; 1873 struct icmp6_hdr *icmp6; 1874 struct mbuf *opts = NULL; 1875 1876#ifndef PULLDOWN_TEST 1877 /* this is assumed to be safe. */ 1878 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off); 1879#else 1880 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 1881 if (icmp6 == NULL) { 1882 /* m is already reclaimed */ 1883 return (IPPROTO_DONE); 1884 } 1885#endif 1886 1887 /* 1888 * XXX: the address may have embedded scope zone ID, which should be 1889 * hidden from applications. 1890 */ 1891 bzero(&fromsa, sizeof(fromsa)); 1892 fromsa.sin6_family = AF_INET6; 1893 fromsa.sin6_len = sizeof(struct sockaddr_in6); 1894 fromsa.sin6_addr = ip6->ip6_src; 1895 if (sa6_recoverscope(&fromsa)) { 1896 m_freem(m); 1897 return (IPPROTO_DONE); 1898 } 1899 1900 INP_INFO_RLOCK(&ripcbinfo); 1901 LIST_FOREACH(in6p, &ripcb, inp_list) { 1902 INP_LOCK(in6p); 1903 if ((in6p->inp_vflag & INP_IPV6) == 0) { 1904 docontinue: 1905 INP_UNLOCK(in6p); 1906 continue; 1907 } 1908 if (in6p->in6p_ip6_nxt != IPPROTO_ICMPV6) 1909 goto docontinue; 1910 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr) && 1911 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr, &ip6->ip6_dst)) 1912 goto docontinue; 1913 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr) && 1914 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr, &ip6->ip6_src)) 1915 goto docontinue; 1916 if (in6p->in6p_icmp6filt 1917 && ICMP6_FILTER_WILLBLOCK(icmp6->icmp6_type, 1918 in6p->in6p_icmp6filt)) 1919 goto docontinue; 1920 if (last) { 1921 struct mbuf *n = NULL; 1922 1923 /* 1924 * Recent network drivers tend to allocate a single 1925 * mbuf cluster, rather than to make a couple of 1926 * mbufs without clusters. Also, since the IPv6 code 1927 * path tries to avoid m_pullup(), it is highly 1928 * probable that we still have an mbuf cluster here 1929 * even though the necessary length can be stored in an 1930 * mbuf's internal buffer. 1931 * Meanwhile, the default size of the receive socket 1932 * buffer for raw sockets is not so large. This means 1933 * the possibility of packet loss is relatively higher 1934 * than before. To avoid this scenario, we copy the 1935 * received data to a separate mbuf that does not use 1936 * a cluster, if possible. 1937 * XXX: it is better to copy the data after stripping 1938 * intermediate headers. 1939 */ 1940 if ((m->m_flags & M_EXT) && m->m_next == NULL && 1941 m->m_len <= MHLEN) { 1942 MGET(n, M_DONTWAIT, m->m_type); 1943 if (n != NULL) { 1944 if (m_dup_pkthdr(n, m, M_NOWAIT)) { 1945 bcopy(m->m_data, n->m_data, 1946 m->m_len); 1947 n->m_len = m->m_len; 1948 } else { 1949 m_free(n); 1950 n = NULL; 1951 } 1952 } 1953 } 1954 if (n != NULL || 1955 (n = m_copy(m, 0, (int)M_COPYALL)) != NULL) { 1956 if (last->in6p_flags & IN6P_CONTROLOPTS) 1957 ip6_savecontrol(last, n, &opts); 1958 /* strip intermediate headers */ 1959 m_adj(n, off); 1960 if (sbappendaddr(&last->in6p_socket->so_rcv, 1961 (struct sockaddr *)&fromsa, n, opts) 1962 == 0) { 1963 /* should notify about lost packet */ 1964 m_freem(n); 1965 if (opts) { 1966 m_freem(opts); 1967 } 1968 } else 1969 sorwakeup(last->in6p_socket); 1970 opts = NULL; 1971 } 1972 INP_UNLOCK(last); 1973 } 1974 last = in6p; 1975 } 1976 if (last) { 1977 if (last->in6p_flags & IN6P_CONTROLOPTS) 1978 ip6_savecontrol(last, m, &opts); 1979 /* strip intermediate headers */ 1980 m_adj(m, off); 1981 1982 /* avoid using mbuf clusters if possible (see above) */ 1983 if ((m->m_flags & M_EXT) && m->m_next == NULL && 1984 m->m_len <= MHLEN) { 1985 struct mbuf *n; 1986 1987 MGET(n, M_DONTWAIT, m->m_type); 1988 if (n != NULL) { 1989 if (m_dup_pkthdr(n, m, M_NOWAIT)) { 1990 bcopy(m->m_data, n->m_data, m->m_len); 1991 n->m_len = m->m_len; 1992 1993 m_freem(m); 1994 m = n; 1995 } else { 1996 m_freem(n); 1997 n = NULL; 1998 } 1999 } 2000 } 2001 if (sbappendaddr(&last->in6p_socket->so_rcv, 2002 (struct sockaddr *)&fromsa, m, opts) == 0) { 2003 m_freem(m); 2004 if (opts) 2005 m_freem(opts); 2006 } else 2007 sorwakeup(last->in6p_socket); 2008 INP_UNLOCK(last); 2009 } else { 2010 m_freem(m); 2011 ip6stat.ip6s_delivered--; 2012 } 2013 INP_INFO_RUNLOCK(&ripcbinfo); 2014 return IPPROTO_DONE; 2015} 2016 2017/* 2018 * Reflect the ip6 packet back to the source. 2019 * OFF points to the icmp6 header, counted from the top of the mbuf. 2020 */ 2021void 2022icmp6_reflect(m, off) 2023 struct mbuf *m; 2024 size_t off; 2025{ 2026 struct ip6_hdr *ip6; 2027 struct icmp6_hdr *icmp6; 2028 struct in6_ifaddr *ia; 2029 int plen; 2030 int type, code; 2031 struct ifnet *outif = NULL; 2032 struct in6_addr origdst, *src = NULL; 2033#ifdef COMPAT_RFC1885 2034 int mtu = IPV6_MMTU; 2035 struct sockaddr_in6 *sin6 = &icmp6_reflect_rt.ro_dst; 2036#endif 2037 2038 /* too short to reflect */ 2039 if (off < sizeof(struct ip6_hdr)) { 2040 nd6log((LOG_DEBUG, 2041 "sanity fail: off=%lx, sizeof(ip6)=%lx in %s:%d\n", 2042 (u_long)off, (u_long)sizeof(struct ip6_hdr), 2043 __FILE__, __LINE__)); 2044 goto bad; 2045 } 2046 2047 /* 2048 * If there are extra headers between IPv6 and ICMPv6, strip 2049 * off that header first. 2050 */ 2051#ifdef DIAGNOSTIC 2052 if (sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) > MHLEN) 2053 panic("assumption failed in icmp6_reflect"); 2054#endif 2055 if (off > sizeof(struct ip6_hdr)) { 2056 size_t l; 2057 struct ip6_hdr nip6; 2058 2059 l = off - sizeof(struct ip6_hdr); 2060 m_copydata(m, 0, sizeof(nip6), (caddr_t)&nip6); 2061 m_adj(m, l); 2062 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 2063 if (m->m_len < l) { 2064 if ((m = m_pullup(m, l)) == NULL) 2065 return; 2066 } 2067 bcopy((caddr_t)&nip6, mtod(m, caddr_t), sizeof(nip6)); 2068 } else /* off == sizeof(struct ip6_hdr) */ { 2069 size_t l; 2070 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 2071 if (m->m_len < l) { 2072 if ((m = m_pullup(m, l)) == NULL) 2073 return; 2074 } 2075 } 2076 plen = m->m_pkthdr.len - sizeof(struct ip6_hdr); 2077 ip6 = mtod(m, struct ip6_hdr *); 2078 ip6->ip6_nxt = IPPROTO_ICMPV6; 2079 icmp6 = (struct icmp6_hdr *)(ip6 + 1); 2080 type = icmp6->icmp6_type; /* keep type for statistics */ 2081 code = icmp6->icmp6_code; /* ditto. */ 2082 2083 origdst = ip6->ip6_dst; 2084 /* 2085 * ip6_input() drops a packet if its src is multicast. 2086 * So, the src is never multicast. 2087 */ 2088 ip6->ip6_dst = ip6->ip6_src; 2089 2090#ifdef COMPAT_RFC1885 2091 /* 2092 * xxx guess MTU 2093 * RFC 1885 requires that echo reply should be truncated if it 2094 * does not fit in with (return) path MTU, but the description was 2095 * removed in the new spec. 2096 */ 2097 if (icmp6_reflect_rt.ro_rt == 0 || 2098 ! (IN6_ARE_ADDR_EQUAL(&sin6->sin6_addr, &ip6->ip6_dst))) { 2099 if (icmp6_reflect_rt.ro_rt) { 2100 RTFREE(icmp6_reflect_rt.ro_rt); 2101 icmp6_reflect_rt.ro_rt = 0; 2102 } 2103 bzero(sin6, sizeof(*sin6)); 2104 sin6->sin6_family = PF_INET6; 2105 sin6->sin6_len = sizeof(struct sockaddr_in6); 2106 sin6->sin6_addr = ip6->ip6_dst; 2107 2108 rtalloc((struct route *)&icmp6_reflect_rt.ro_rt); 2109 } 2110 2111 if (icmp6_reflect_rt.ro_rt == 0) 2112 goto bad; 2113 2114 if ((icmp6_reflect_rt.ro_rt->rt_flags & RTF_HOST) 2115 && mtu < icmp6_reflect_rt.ro_rt->rt_ifp->if_mtu) 2116 mtu = icmp6_reflect_rt.ro_rt->rt_rmx.rmx_mtu; 2117 2118 if (mtu < m->m_pkthdr.len) { 2119 plen -= (m->m_pkthdr.len - mtu); 2120 m_adj(m, mtu - m->m_pkthdr.len); 2121 } 2122#endif 2123 2124 /* 2125 * If the incoming packet was addressed directly to us (i.e. unicast), 2126 * use dst as the src for the reply. 2127 * The IN6_IFF_NOTREADY case should be VERY rare, but is possible 2128 * (for example) when we encounter an error while forwarding procedure 2129 * destined to a duplicated address of ours. 2130 * Note that ip6_getdstifaddr() may fail if we are in an error handling 2131 * procedure of an outgoing packet of our own, in which case we need 2132 * to search in the ifaddr list. 2133 */ 2134 if (!IN6_IS_ADDR_MULTICAST(&origdst)) { 2135 if ((ia = ip6_getdstifaddr(m))) { 2136 if (!(ia->ia6_flags & 2137 (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY))) 2138 src = &ia->ia_addr.sin6_addr; 2139 } else { 2140 struct sockaddr_in6 d; 2141 2142 bzero(&d, sizeof(d)); 2143 d.sin6_family = AF_INET6; 2144 d.sin6_len = sizeof(d); 2145 d.sin6_addr = origdst; 2146 ia = (struct in6_ifaddr *) 2147 ifa_ifwithaddr((struct sockaddr *)&d); 2148 if (ia && 2149 !(ia->ia6_flags & 2150 (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY))) { 2151 src = &ia->ia_addr.sin6_addr; 2152 } 2153 } 2154 } 2155 2156 if (src == NULL) { 2157 int e; 2158 struct sockaddr_in6 sin6; 2159 struct route_in6 ro; 2160 2161 /* 2162 * This case matches to multicasts, our anycast, or unicasts 2163 * that we do not own. Select a source address based on the 2164 * source address of the erroneous packet. 2165 */ 2166 bzero(&sin6, sizeof(sin6)); 2167 sin6.sin6_family = AF_INET6; 2168 sin6.sin6_len = sizeof(sin6); 2169 sin6.sin6_addr = ip6->ip6_dst; /* zone ID should be embedded */ 2170 2171 bzero(&ro, sizeof(ro)); 2172 src = in6_selectsrc(&sin6, NULL, NULL, &ro, NULL, &outif, &e); 2173 if (ro.ro_rt) 2174 RTFREE(ro.ro_rt); /* XXX: we could use this */ 2175 if (src == NULL) { 2176 nd6log((LOG_DEBUG, 2177 "icmp6_reflect: source can't be determined: " 2178 "dst=%s, error=%d\n", 2179 ip6_sprintf(&sin6.sin6_addr), e)); 2180 goto bad; 2181 } 2182 } 2183 2184 ip6->ip6_src = *src; 2185 ip6->ip6_flow = 0; 2186 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2187 ip6->ip6_vfc |= IPV6_VERSION; 2188 ip6->ip6_nxt = IPPROTO_ICMPV6; 2189 if (outif) 2190 ip6->ip6_hlim = ND_IFINFO(outif)->chlim; 2191 else if (m->m_pkthdr.rcvif) { 2192 /* XXX: This may not be the outgoing interface */ 2193 ip6->ip6_hlim = ND_IFINFO(m->m_pkthdr.rcvif)->chlim; 2194 } else 2195 ip6->ip6_hlim = ip6_defhlim; 2196 2197 icmp6->icmp6_cksum = 0; 2198 icmp6->icmp6_cksum = in6_cksum(m, IPPROTO_ICMPV6, 2199 sizeof(struct ip6_hdr), plen); 2200 2201 /* 2202 * XXX option handling 2203 */ 2204 2205 m->m_flags &= ~(M_BCAST|M_MCAST); 2206 2207#ifdef COMPAT_RFC1885 2208 ip6_output(m, NULL, &icmp6_reflect_rt, 0, NULL, &outif, NULL); 2209#else 2210 ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL); 2211#endif 2212 if (outif) 2213 icmp6_ifoutstat_inc(outif, type, code); 2214 2215 return; 2216 2217 bad: 2218 m_freem(m); 2219 return; 2220} 2221 2222void 2223icmp6_fasttimo() 2224{ 2225 2226 mld6_fasttimeo(); 2227} 2228 2229static const char * 2230icmp6_redirect_diag(src6, dst6, tgt6) 2231 struct in6_addr *src6; 2232 struct in6_addr *dst6; 2233 struct in6_addr *tgt6; 2234{ 2235 static char buf[1024]; 2236 snprintf(buf, sizeof(buf), "(src=%s dst=%s tgt=%s)", 2237 ip6_sprintf(src6), ip6_sprintf(dst6), ip6_sprintf(tgt6)); 2238 return buf; 2239} 2240 2241void 2242icmp6_redirect_input(m, off) 2243 struct mbuf *m; 2244 int off; 2245{ 2246 struct ifnet *ifp = m->m_pkthdr.rcvif; 2247 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 2248 struct nd_redirect *nd_rd; 2249 int icmp6len = ntohs(ip6->ip6_plen); 2250 char *lladdr = NULL; 2251 int lladdrlen = 0; 2252 u_char *redirhdr = NULL; 2253 int redirhdrlen = 0; 2254 struct rtentry *rt = NULL; 2255 int is_router; 2256 int is_onlink; 2257 struct in6_addr src6 = ip6->ip6_src; 2258 struct in6_addr redtgt6; 2259 struct in6_addr reddst6; 2260 union nd_opts ndopts; 2261 2262 if (!m || !ifp) 2263 return; 2264 2265 /* XXX if we are router, we don't update route by icmp6 redirect */ 2266 if (ip6_forwarding) 2267 goto freeit; 2268 if (!icmp6_rediraccept) 2269 goto freeit; 2270 2271#ifndef PULLDOWN_TEST 2272 IP6_EXTHDR_CHECK(m, off, icmp6len,); 2273 nd_rd = (struct nd_redirect *)((caddr_t)ip6 + off); 2274#else 2275 IP6_EXTHDR_GET(nd_rd, struct nd_redirect *, m, off, icmp6len); 2276 if (nd_rd == NULL) { 2277 icmp6stat.icp6s_tooshort++; 2278 return; 2279 } 2280#endif 2281 redtgt6 = nd_rd->nd_rd_target; 2282 reddst6 = nd_rd->nd_rd_dst; 2283 2284 if (in6_setscope(&redtgt6, m->m_pkthdr.rcvif, NULL) || 2285 in6_setscope(&reddst6, m->m_pkthdr.rcvif, NULL)) { 2286 goto freeit; 2287 } 2288 2289 /* validation */ 2290 if (!IN6_IS_ADDR_LINKLOCAL(&src6)) { 2291 nd6log((LOG_ERR, 2292 "ICMP6 redirect sent from %s rejected; " 2293 "must be from linklocal\n", 2294 ip6_sprintf(&src6))); 2295 goto bad; 2296 } 2297 if (ip6->ip6_hlim != 255) { 2298 nd6log((LOG_ERR, 2299 "ICMP6 redirect sent from %s rejected; " 2300 "hlim=%d (must be 255)\n", 2301 ip6_sprintf(&src6), ip6->ip6_hlim)); 2302 goto bad; 2303 } 2304 { 2305 /* ip6->ip6_src must be equal to gw for icmp6->icmp6_reddst */ 2306 struct sockaddr_in6 sin6; 2307 struct in6_addr *gw6; 2308 2309 bzero(&sin6, sizeof(sin6)); 2310 sin6.sin6_family = AF_INET6; 2311 sin6.sin6_len = sizeof(struct sockaddr_in6); 2312 bcopy(&reddst6, &sin6.sin6_addr, sizeof(reddst6)); 2313 rt = rtalloc1((struct sockaddr *)&sin6, 0, 0UL); 2314 if (rt) { 2315 if (rt->rt_gateway == NULL || 2316 rt->rt_gateway->sa_family != AF_INET6) { 2317 nd6log((LOG_ERR, 2318 "ICMP6 redirect rejected; no route " 2319 "with inet6 gateway found for redirect dst: %s\n", 2320 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2321 RTFREE_LOCKED(rt); 2322 goto bad; 2323 } 2324 2325 gw6 = &(((struct sockaddr_in6 *)rt->rt_gateway)->sin6_addr); 2326 if (bcmp(&src6, gw6, sizeof(struct in6_addr)) != 0) { 2327 nd6log((LOG_ERR, 2328 "ICMP6 redirect rejected; " 2329 "not equal to gw-for-src=%s (must be same): " 2330 "%s\n", 2331 ip6_sprintf(gw6), 2332 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2333 RTFREE_LOCKED(rt); 2334 goto bad; 2335 } 2336 } else { 2337 nd6log((LOG_ERR, 2338 "ICMP6 redirect rejected; " 2339 "no route found for redirect dst: %s\n", 2340 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2341 goto bad; 2342 } 2343 RTFREE_LOCKED(rt); 2344 rt = NULL; 2345 } 2346 if (IN6_IS_ADDR_MULTICAST(&reddst6)) { 2347 nd6log((LOG_ERR, 2348 "ICMP6 redirect rejected; " 2349 "redirect dst must be unicast: %s\n", 2350 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2351 goto bad; 2352 } 2353 2354 is_router = is_onlink = 0; 2355 if (IN6_IS_ADDR_LINKLOCAL(&redtgt6)) 2356 is_router = 1; /* router case */ 2357 if (bcmp(&redtgt6, &reddst6, sizeof(redtgt6)) == 0) 2358 is_onlink = 1; /* on-link destination case */ 2359 if (!is_router && !is_onlink) { 2360 nd6log((LOG_ERR, 2361 "ICMP6 redirect rejected; " 2362 "neither router case nor onlink case: %s\n", 2363 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2364 goto bad; 2365 } 2366 /* validation passed */ 2367 2368 icmp6len -= sizeof(*nd_rd); 2369 nd6_option_init(nd_rd + 1, icmp6len, &ndopts); 2370 if (nd6_options(&ndopts) < 0) { 2371 nd6log((LOG_INFO, "icmp6_redirect_input: " 2372 "invalid ND option, rejected: %s\n", 2373 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2374 /* nd6_options have incremented stats */ 2375 goto freeit; 2376 } 2377 2378 if (ndopts.nd_opts_tgt_lladdr) { 2379 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 2380 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 2381 } 2382 2383 if (ndopts.nd_opts_rh) { 2384 redirhdrlen = ndopts.nd_opts_rh->nd_opt_rh_len; 2385 redirhdr = (u_char *)(ndopts.nd_opts_rh + 1); /* xxx */ 2386 } 2387 2388 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 2389 nd6log((LOG_INFO, 2390 "icmp6_redirect_input: lladdrlen mismatch for %s " 2391 "(if %d, icmp6 packet %d): %s\n", 2392 ip6_sprintf(&redtgt6), ifp->if_addrlen, lladdrlen - 2, 2393 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2394 goto bad; 2395 } 2396 2397 /* RFC 2461 8.3 */ 2398 nd6_cache_lladdr(ifp, &redtgt6, lladdr, lladdrlen, ND_REDIRECT, 2399 is_onlink ? ND_REDIRECT_ONLINK : ND_REDIRECT_ROUTER); 2400 2401 if (!is_onlink) { /* better router case. perform rtredirect. */ 2402 /* perform rtredirect */ 2403 struct sockaddr_in6 sdst; 2404 struct sockaddr_in6 sgw; 2405 struct sockaddr_in6 ssrc; 2406 2407 bzero(&sdst, sizeof(sdst)); 2408 bzero(&sgw, sizeof(sgw)); 2409 bzero(&ssrc, sizeof(ssrc)); 2410 sdst.sin6_family = sgw.sin6_family = ssrc.sin6_family = AF_INET6; 2411 sdst.sin6_len = sgw.sin6_len = ssrc.sin6_len = 2412 sizeof(struct sockaddr_in6); 2413 bcopy(&redtgt6, &sgw.sin6_addr, sizeof(struct in6_addr)); 2414 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2415 bcopy(&src6, &ssrc.sin6_addr, sizeof(struct in6_addr)); 2416 rtredirect((struct sockaddr *)&sdst, (struct sockaddr *)&sgw, 2417 (struct sockaddr *)NULL, RTF_GATEWAY | RTF_HOST, 2418 (struct sockaddr *)&ssrc); 2419 } 2420 /* finally update cached route in each socket via pfctlinput */ 2421 { 2422 struct sockaddr_in6 sdst; 2423 2424 bzero(&sdst, sizeof(sdst)); 2425 sdst.sin6_family = AF_INET6; 2426 sdst.sin6_len = sizeof(struct sockaddr_in6); 2427 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2428 pfctlinput(PRC_REDIRECT_HOST, (struct sockaddr *)&sdst); 2429#if defined(IPSEC) || defined(FAST_IPSEC) 2430 key_sa_routechange((struct sockaddr *)&sdst); 2431#endif 2432 } 2433 2434 freeit: 2435 m_freem(m); 2436 return; 2437 2438 bad: 2439 icmp6stat.icp6s_badredirect++; 2440 m_freem(m); 2441} 2442 2443void 2444icmp6_redirect_output(m0, rt) 2445 struct mbuf *m0; 2446 struct rtentry *rt; 2447{ 2448 struct ifnet *ifp; /* my outgoing interface */ 2449 struct in6_addr *ifp_ll6; 2450 struct in6_addr *router_ll6; 2451 struct ip6_hdr *sip6; /* m0 as struct ip6_hdr */ 2452 struct mbuf *m = NULL; /* newly allocated one */ 2453 struct ip6_hdr *ip6; /* m as struct ip6_hdr */ 2454 struct nd_redirect *nd_rd; 2455 size_t maxlen; 2456 u_char *p; 2457 struct ifnet *outif = NULL; 2458 struct sockaddr_in6 src_sa; 2459 2460 icmp6_errcount(&icmp6stat.icp6s_outerrhist, ND_REDIRECT, 0); 2461 2462 /* if we are not router, we don't send icmp6 redirect */ 2463 if (!ip6_forwarding || ip6_accept_rtadv) 2464 goto fail; 2465 2466 /* sanity check */ 2467 if (!m0 || !rt || !(rt->rt_flags & RTF_UP) || !(ifp = rt->rt_ifp)) 2468 goto fail; 2469 2470 /* 2471 * Address check: 2472 * the source address must identify a neighbor, and 2473 * the destination address must not be a multicast address 2474 * [RFC 2461, sec 8.2] 2475 */ 2476 sip6 = mtod(m0, struct ip6_hdr *); 2477 bzero(&src_sa, sizeof(src_sa)); 2478 src_sa.sin6_family = AF_INET6; 2479 src_sa.sin6_len = sizeof(src_sa); 2480 src_sa.sin6_addr = sip6->ip6_src; 2481 if (nd6_is_addr_neighbor(&src_sa, ifp) == 0) 2482 goto fail; 2483 if (IN6_IS_ADDR_MULTICAST(&sip6->ip6_dst)) 2484 goto fail; /* what should we do here? */ 2485 2486 /* rate limit */ 2487 if (icmp6_ratelimit(&sip6->ip6_src, ND_REDIRECT, 0)) 2488 goto fail; 2489 2490 /* 2491 * Since we are going to append up to 1280 bytes (= IPV6_MMTU), 2492 * we almost always ask for an mbuf cluster for simplicity. 2493 * (MHLEN < IPV6_MMTU is almost always true) 2494 */ 2495#if IPV6_MMTU >= MCLBYTES 2496# error assumption failed about IPV6_MMTU and MCLBYTES 2497#endif 2498 MGETHDR(m, M_DONTWAIT, MT_HEADER); 2499 if (m && IPV6_MMTU >= MHLEN) 2500 MCLGET(m, M_DONTWAIT); 2501 if (!m) 2502 goto fail; 2503 m->m_pkthdr.rcvif = NULL; 2504 m->m_len = 0; 2505 maxlen = M_TRAILINGSPACE(m); 2506 maxlen = min(IPV6_MMTU, maxlen); 2507 /* just for safety */ 2508 if (maxlen < sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) + 2509 ((sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7)) { 2510 goto fail; 2511 } 2512 2513 { 2514 /* get ip6 linklocal address for ifp(my outgoing interface). */ 2515 struct in6_ifaddr *ia; 2516 if ((ia = in6ifa_ifpforlinklocal(ifp, 2517 IN6_IFF_NOTREADY| 2518 IN6_IFF_ANYCAST)) == NULL) 2519 goto fail; 2520 ifp_ll6 = &ia->ia_addr.sin6_addr; 2521 } 2522 2523 /* get ip6 linklocal address for the router. */ 2524 if (rt->rt_gateway && (rt->rt_flags & RTF_GATEWAY)) { 2525 struct sockaddr_in6 *sin6; 2526 sin6 = (struct sockaddr_in6 *)rt->rt_gateway; 2527 router_ll6 = &sin6->sin6_addr; 2528 if (!IN6_IS_ADDR_LINKLOCAL(router_ll6)) 2529 router_ll6 = (struct in6_addr *)NULL; 2530 } else 2531 router_ll6 = (struct in6_addr *)NULL; 2532 2533 /* ip6 */ 2534 ip6 = mtod(m, struct ip6_hdr *); 2535 ip6->ip6_flow = 0; 2536 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2537 ip6->ip6_vfc |= IPV6_VERSION; 2538 /* ip6->ip6_plen will be set later */ 2539 ip6->ip6_nxt = IPPROTO_ICMPV6; 2540 ip6->ip6_hlim = 255; 2541 /* ip6->ip6_src must be linklocal addr for my outgoing if. */ 2542 bcopy(ifp_ll6, &ip6->ip6_src, sizeof(struct in6_addr)); 2543 bcopy(&sip6->ip6_src, &ip6->ip6_dst, sizeof(struct in6_addr)); 2544 2545 /* ND Redirect */ 2546 nd_rd = (struct nd_redirect *)(ip6 + 1); 2547 nd_rd->nd_rd_type = ND_REDIRECT; 2548 nd_rd->nd_rd_code = 0; 2549 nd_rd->nd_rd_reserved = 0; 2550 if (rt->rt_flags & RTF_GATEWAY) { 2551 /* 2552 * nd_rd->nd_rd_target must be a link-local address in 2553 * better router cases. 2554 */ 2555 if (!router_ll6) 2556 goto fail; 2557 bcopy(router_ll6, &nd_rd->nd_rd_target, 2558 sizeof(nd_rd->nd_rd_target)); 2559 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2560 sizeof(nd_rd->nd_rd_dst)); 2561 } else { 2562 /* make sure redtgt == reddst */ 2563 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_target, 2564 sizeof(nd_rd->nd_rd_target)); 2565 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2566 sizeof(nd_rd->nd_rd_dst)); 2567 } 2568 2569 p = (u_char *)(nd_rd + 1); 2570 2571 if (!router_ll6) 2572 goto nolladdropt; 2573 2574 { 2575 /* target lladdr option */ 2576 struct rtentry *rt_router = NULL; 2577 int len; 2578 struct sockaddr_dl *sdl; 2579 struct nd_opt_hdr *nd_opt; 2580 char *lladdr; 2581 2582 rt_router = nd6_lookup(router_ll6, 0, ifp); 2583 if (!rt_router) 2584 goto nolladdropt; 2585 len = sizeof(*nd_opt) + ifp->if_addrlen; 2586 len = (len + 7) & ~7; /* round by 8 */ 2587 /* safety check */ 2588 if (len + (p - (u_char *)ip6) > maxlen) 2589 goto nolladdropt; 2590 if (!(rt_router->rt_flags & RTF_GATEWAY) && 2591 (rt_router->rt_flags & RTF_LLINFO) && 2592 (rt_router->rt_gateway->sa_family == AF_LINK) && 2593 (sdl = (struct sockaddr_dl *)rt_router->rt_gateway) && 2594 sdl->sdl_alen) { 2595 nd_opt = (struct nd_opt_hdr *)p; 2596 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 2597 nd_opt->nd_opt_len = len >> 3; 2598 lladdr = (char *)(nd_opt + 1); 2599 bcopy(LLADDR(sdl), lladdr, ifp->if_addrlen); 2600 p += len; 2601 } 2602 } 2603nolladdropt:; 2604 2605 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2606 2607 /* just to be safe */ 2608#ifdef M_DECRYPTED /*not openbsd*/ 2609 if (m0->m_flags & M_DECRYPTED) 2610 goto noredhdropt; 2611#endif 2612 if (p - (u_char *)ip6 > maxlen) 2613 goto noredhdropt; 2614 2615 { 2616 /* redirected header option */ 2617 int len; 2618 struct nd_opt_rd_hdr *nd_opt_rh; 2619 2620 /* 2621 * compute the maximum size for icmp6 redirect header option. 2622 * XXX room for auth header? 2623 */ 2624 len = maxlen - (p - (u_char *)ip6); 2625 len &= ~7; 2626 2627 /* This is just for simplicity. */ 2628 if (m0->m_pkthdr.len != m0->m_len) { 2629 if (m0->m_next) { 2630 m_freem(m0->m_next); 2631 m0->m_next = NULL; 2632 } 2633 m0->m_pkthdr.len = m0->m_len; 2634 } 2635 2636 /* 2637 * Redirected header option spec (RFC2461 4.6.3) talks nothing 2638 * about padding/truncate rule for the original IP packet. 2639 * From the discussion on IPv6imp in Feb 1999, 2640 * the consensus was: 2641 * - "attach as much as possible" is the goal 2642 * - pad if not aligned (original size can be guessed by 2643 * original ip6 header) 2644 * Following code adds the padding if it is simple enough, 2645 * and truncates if not. 2646 */ 2647 if (m0->m_next || m0->m_pkthdr.len != m0->m_len) 2648 panic("assumption failed in %s:%d", __FILE__, 2649 __LINE__); 2650 2651 if (len - sizeof(*nd_opt_rh) < m0->m_pkthdr.len) { 2652 /* not enough room, truncate */ 2653 m0->m_pkthdr.len = m0->m_len = len - 2654 sizeof(*nd_opt_rh); 2655 } else { 2656 /* enough room, pad or truncate */ 2657 size_t extra; 2658 2659 extra = m0->m_pkthdr.len % 8; 2660 if (extra) { 2661 /* pad if easy enough, truncate if not */ 2662 if (8 - extra <= M_TRAILINGSPACE(m0)) { 2663 /* pad */ 2664 m0->m_len += (8 - extra); 2665 m0->m_pkthdr.len += (8 - extra); 2666 } else { 2667 /* truncate */ 2668 m0->m_pkthdr.len -= extra; 2669 m0->m_len -= extra; 2670 } 2671 } 2672 len = m0->m_pkthdr.len + sizeof(*nd_opt_rh); 2673 m0->m_pkthdr.len = m0->m_len = len - 2674 sizeof(*nd_opt_rh); 2675 } 2676 2677 nd_opt_rh = (struct nd_opt_rd_hdr *)p; 2678 bzero(nd_opt_rh, sizeof(*nd_opt_rh)); 2679 nd_opt_rh->nd_opt_rh_type = ND_OPT_REDIRECTED_HEADER; 2680 nd_opt_rh->nd_opt_rh_len = len >> 3; 2681 p += sizeof(*nd_opt_rh); 2682 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2683 2684 /* connect m0 to m */ 2685 m_tag_delete_chain(m0, NULL); 2686 m0->m_flags &= ~M_PKTHDR; 2687 m->m_next = m0; 2688 m->m_pkthdr.len = m->m_len + m0->m_len; 2689 m0 = NULL; 2690 } 2691noredhdropt:; 2692 if (m0) { 2693 m_freem(m0); 2694 m0 = NULL; 2695 } 2696 2697 /* XXX: clear embedded link IDs in the inner header */ 2698 in6_clearscope(&sip6->ip6_src); 2699 in6_clearscope(&sip6->ip6_dst); 2700 in6_clearscope(&nd_rd->nd_rd_target); 2701 in6_clearscope(&nd_rd->nd_rd_dst); 2702 2703 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr)); 2704 2705 nd_rd->nd_rd_cksum = 0; 2706 nd_rd->nd_rd_cksum = in6_cksum(m, IPPROTO_ICMPV6, 2707 sizeof(*ip6), ntohs(ip6->ip6_plen)); 2708 2709 /* send the packet to outside... */ 2710 ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL); 2711 if (outif) { 2712 icmp6_ifstat_inc(outif, ifs6_out_msg); 2713 icmp6_ifstat_inc(outif, ifs6_out_redirect); 2714 } 2715 icmp6stat.icp6s_outhist[ND_REDIRECT]++; 2716 2717 return; 2718 2719fail: 2720 if (m) 2721 m_freem(m); 2722 if (m0) 2723 m_freem(m0); 2724} 2725 2726/* 2727 * ICMPv6 socket option processing. 2728 */ 2729int 2730icmp6_ctloutput(so, sopt) 2731 struct socket *so; 2732 struct sockopt *sopt; 2733{ 2734 int error = 0; 2735 int optlen; 2736 struct inpcb *inp = sotoinpcb(so); 2737 int level, op, optname; 2738 2739 if (sopt) { 2740 level = sopt->sopt_level; 2741 op = sopt->sopt_dir; 2742 optname = sopt->sopt_name; 2743 optlen = sopt->sopt_valsize; 2744 } else 2745 level = op = optname = optlen = 0; 2746 2747 if (level != IPPROTO_ICMPV6) { 2748 return EINVAL; 2749 } 2750 2751 switch (op) { 2752 case PRCO_SETOPT: 2753 switch (optname) { 2754 case ICMP6_FILTER: 2755 { 2756 struct icmp6_filter *p; 2757 2758 if (optlen != sizeof(*p)) { 2759 error = EMSGSIZE; 2760 break; 2761 } 2762 if (inp->in6p_icmp6filt == NULL) { 2763 error = EINVAL; 2764 break; 2765 } 2766 error = sooptcopyin(sopt, inp->in6p_icmp6filt, optlen, 2767 optlen); 2768 break; 2769 } 2770 2771 default: 2772 error = ENOPROTOOPT; 2773 break; 2774 } 2775 break; 2776 2777 case PRCO_GETOPT: 2778 switch (optname) { 2779 case ICMP6_FILTER: 2780 { 2781 if (inp->in6p_icmp6filt == NULL) { 2782 error = EINVAL; 2783 break; 2784 } 2785 error = sooptcopyout(sopt, inp->in6p_icmp6filt, 2786 sizeof(struct icmp6_filter)); 2787 break; 2788 } 2789 2790 default: 2791 error = ENOPROTOOPT; 2792 break; 2793 } 2794 break; 2795 } 2796 2797 return (error); 2798} 2799 2800/* 2801 * Perform rate limit check. 2802 * Returns 0 if it is okay to send the icmp6 packet. 2803 * Returns 1 if the router SHOULD NOT send this icmp6 packet due to rate 2804 * limitation. 2805 * 2806 * XXX per-destination/type check necessary? 2807 */ 2808static int 2809icmp6_ratelimit(dst, type, code) 2810 const struct in6_addr *dst; /* not used at this moment */ 2811 const int type; /* not used at this moment */ 2812 const int code; /* not used at this moment */ 2813{ 2814 int ret; 2815 2816 ret = 0; /* okay to send */ 2817 2818 /* PPS limit */ 2819 if (!ppsratecheck(&icmp6errppslim_last, &icmp6errpps_count, 2820 icmp6errppslim)) { 2821 /* The packet is subject to rate limit */ 2822 ret++; 2823 } 2824 2825 return ret; 2826} 2827