Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)
[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]
FreeBSD/Linux Kernel Cross Reference
sys/netinet6/icmp6.c
Version:
- FREEBSD - FREEBSD-13-STABLE - FREEBSD-13-0 - FREEBSD-12-STABLE - FREEBSD-12-0 - FREEBSD-11-STABLE - FREEBSD-11-0 - FREEBSD-10-STABLE - FREEBSD-10-0 - FREEBSD-9-STABLE - FREEBSD-9-0 - FREEBSD-8-STABLE - FREEBSD-8-0 - FREEBSD-7-STABLE - FREEBSD-7-0 - FREEBSD-6-STABLE - FREEBSD-6-0 - FREEBSD-5-STABLE - FREEBSD-5-0 - FREEBSD-4-STABLE - FREEBSD-3-STABLE - FREEBSD22 - l41 - OPENBSD - linux-2.6 - MK84 - PLAN9 - xnu-8792
SearchContext: - none - 3 - 10
SearchContext: - none - 3 - 10
1 /*- 2 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of the project nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * $KAME: icmp6.c,v 1.211 2001/04/04 05:56:20 itojun Exp $ 30 */ 31 32 /*- 33 * Copyright (c) 1982, 1986, 1988, 1993 34 * The Regents of the University of California. All rights reserved. 35 * 36 * Redistribution and use in source and binary forms, with or without 37 * modification, are permitted provided that the following conditions 38 * are met: 39 * 1. Redistributions of source code must retain the above copyright 40 * notice, this list of conditions and the following disclaimer. 41 * 2. Redistributions in binary form must reproduce the above copyright 42 * notice, this list of conditions and the following disclaimer in the 43 * documentation and/or other materials provided with the distribution. 44 * 4. Neither the name of the University nor the names of its contributors 45 * may be used to endorse or promote products derived from this software 46 * without specific prior written permission. 47 * 48 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 49 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 50 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 51 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 52 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 53 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 54 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 55 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 56 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 57 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 58 * SUCH DAMAGE. 59 * 60 * @(#)ip_icmp.c 8.2 (Berkeley) 1/4/94 61 */ 62 63 #include <sys/cdefs.h> 64 __FBSDID("$FreeBSD: releng/6.4/sys/netinet6/icmp6.c 182740 2008-09-03 19:09:47Z simon $"); 65 66 #include "opt_inet.h" 67 #include "opt_inet6.h" 68 #include "opt_ipsec.h" 69 70 #include <sys/param.h> 71 #include <sys/domain.h> 72 #include <sys/kernel.h> 73 #include <sys/lock.h> 74 #include <sys/malloc.h> 75 #include <sys/mbuf.h> 76 #include <sys/protosw.h> 77 #include <sys/signalvar.h> 78 #include <sys/socket.h> 79 #include <sys/socketvar.h> 80 #include <sys/sx.h> 81 #include <sys/syslog.h> 82 #include <sys/systm.h> 83 #include <sys/time.h> 84 85 #include <net/if.h> 86 #include <net/if_dl.h> 87 #include <net/if_types.h> 88 #include <net/route.h> 89 90 #include <netinet/in.h> 91 #include <netinet/in_pcb.h> 92 #include <netinet/in_var.h> 93 #include <netinet/ip6.h> 94 #include <netinet/icmp6.h> 95 #include <netinet/tcp_var.h> 96 #include <netinet6/in6_ifattach.h> 97 #include <netinet6/in6_pcb.h> 98 #include <netinet6/ip6protosw.h> 99 #include <netinet6/ip6_var.h> 100 #include <netinet6/scope6_var.h> 101 #include <netinet6/mld6_var.h> 102 #include <netinet6/nd6.h> 103 104 #ifdef IPSEC 105 #include <netinet6/ipsec.h> 106 #include <netkey/key.h> 107 #endif 108 109 #ifdef FAST_IPSEC 110 #include <netipsec/ipsec.h> 111 #include <netipsec/key.h> 112 #endif 113 114 #include <net/net_osdep.h> 115 116 extern struct domain inet6domain; 117 118 struct icmp6stat icmp6stat; 119 120 extern struct inpcbinfo ripcbinfo; 121 extern struct inpcbhead ripcb; 122 extern int icmp6errppslim; 123 static int icmp6errpps_count = 0; 124 static struct timeval icmp6errppslim_last; 125 extern int icmp6_nodeinfo; 126 127 static void icmp6_errcount(struct icmp6errstat *, int, int); 128 static int icmp6_rip6_input(struct mbuf **, int); 129 static int icmp6_ratelimit(const struct in6_addr *, const int, const int); 130 static const char *icmp6_redirect_diag __P((struct in6_addr *, 131 struct in6_addr *, struct in6_addr *)); 132 static struct mbuf *ni6_input(struct mbuf *, int); 133 static struct mbuf *ni6_nametodns(const char *, int, int); 134 static int ni6_dnsmatch(const char *, int, const char *, int); 135 static int ni6_addrs __P((struct icmp6_nodeinfo *, struct mbuf *, 136 struct ifnet **, struct in6_addr *)); 137 static int ni6_store_addrs __P((struct icmp6_nodeinfo *, struct icmp6_nodeinfo *, 138 struct ifnet *, int)); 139 static int icmp6_notify_error(struct mbuf **, int, int, int); 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 * A wrapper function for icmp6_error() necessary when the erroneous packet 208 * may not contain enough scope zone information. 209 */ 210 void 211 icmp6_error2(m, type, code, param, ifp) 212 struct mbuf *m; 213 int type, code, param; 214 struct ifnet *ifp; 215 { 216 struct ip6_hdr *ip6; 217 218 if (ifp == NULL) 219 return; 220 221 #ifndef PULLDOWN_TEST 222 IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), ); 223 #else 224 if (m->m_len < sizeof(struct ip6_hdr)) { 225 m = m_pullup(m, sizeof(struct ip6_hdr)); 226 if (m == NULL) 227 return; 228 } 229 #endif 230 231 ip6 = mtod(m, struct ip6_hdr *); 232 233 if (in6_setscope(&ip6->ip6_src, ifp, NULL) != 0) 234 return; 235 if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0) 236 return; 237 238 icmp6_error(m, type, code, param); 239 } 240 241 /* 242 * Generate an error packet of type error in response to bad IP6 packet. 243 */ 244 void 245 icmp6_error(m, type, code, param) 246 struct mbuf *m; 247 int type, code, param; 248 { 249 struct ip6_hdr *oip6, *nip6; 250 struct icmp6_hdr *icmp6; 251 u_int preplen; 252 int off; 253 int nxt; 254 255 icmp6stat.icp6s_error++; 256 257 /* count per-type-code statistics */ 258 icmp6_errcount(&icmp6stat.icp6s_outerrhist, type, code); 259 260 #ifdef M_DECRYPTED /*not openbsd*/ 261 if (m->m_flags & M_DECRYPTED) { 262 icmp6stat.icp6s_canterror++; 263 goto freeit; 264 } 265 #endif 266 267 #ifndef PULLDOWN_TEST 268 IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), ); 269 #else 270 if (m->m_len < sizeof(struct ip6_hdr)) { 271 m = m_pullup(m, sizeof(struct ip6_hdr)); 272 if (m == NULL) 273 return; 274 } 275 #endif 276 oip6 = mtod(m, struct ip6_hdr *); 277 278 /* 279 * If the destination address of the erroneous packet is a multicast 280 * address, or the packet was sent using link-layer multicast, 281 * we should basically suppress sending an error (RFC 2463, Section 282 * 2.4). 283 * We have two exceptions (the item e.2 in that section): 284 * - the Pakcet Too Big message can be sent for path MTU discovery. 285 * - the Parameter Problem Message that can be allowed an icmp6 error 286 * in the option type field. This check has been done in 287 * ip6_unknown_opt(), so we can just check the type and code. 288 */ 289 if ((m->m_flags & (M_BCAST|M_MCAST) || 290 IN6_IS_ADDR_MULTICAST(&oip6->ip6_dst)) && 291 (type != ICMP6_PACKET_TOO_BIG && 292 (type != ICMP6_PARAM_PROB || 293 code != ICMP6_PARAMPROB_OPTION))) 294 goto freeit; 295 296 /* 297 * RFC 2463, 2.4 (e.5): source address check. 298 * XXX: the case of anycast source? 299 */ 300 if (IN6_IS_ADDR_UNSPECIFIED(&oip6->ip6_src) || 301 IN6_IS_ADDR_MULTICAST(&oip6->ip6_src)) 302 goto freeit; 303 304 /* 305 * If we are about to send ICMPv6 against ICMPv6 error/redirect, 306 * don't do it. 307 */ 308 nxt = -1; 309 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); 310 if (off >= 0 && nxt == IPPROTO_ICMPV6) { 311 struct icmp6_hdr *icp; 312 313 #ifndef PULLDOWN_TEST 314 IP6_EXTHDR_CHECK(m, 0, off + sizeof(struct icmp6_hdr), ); 315 icp = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 316 #else 317 IP6_EXTHDR_GET(icp, struct icmp6_hdr *, m, off, 318 sizeof(*icp)); 319 if (icp == NULL) { 320 icmp6stat.icp6s_tooshort++; 321 return; 322 } 323 #endif 324 if (icp->icmp6_type < ICMP6_ECHO_REQUEST || 325 icp->icmp6_type == ND_REDIRECT) { 326 /* 327 * ICMPv6 error 328 * Special case: for redirect (which is 329 * informational) we must not send icmp6 error. 330 */ 331 icmp6stat.icp6s_canterror++; 332 goto freeit; 333 } else { 334 /* ICMPv6 informational - send the error */ 335 } 336 } else { 337 /* non-ICMPv6 - send the error */ 338 } 339 340 oip6 = mtod(m, struct ip6_hdr *); /* adjust pointer */ 341 342 /* Finally, do rate limitation check. */ 343 if (icmp6_ratelimit(&oip6->ip6_src, type, code)) { 344 icmp6stat.icp6s_toofreq++; 345 goto freeit; 346 } 347 348 /* 349 * OK, ICMP6 can be generated. 350 */ 351 352 if (m->m_pkthdr.len >= ICMPV6_PLD_MAXLEN) 353 m_adj(m, ICMPV6_PLD_MAXLEN - m->m_pkthdr.len); 354 355 preplen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 356 M_PREPEND(m, preplen, M_DONTWAIT); 357 if (m && m->m_len < preplen) 358 m = m_pullup(m, preplen); 359 if (m == NULL) { 360 nd6log((LOG_DEBUG, "ENOBUFS in icmp6_error %d\n", __LINE__)); 361 return; 362 } 363 364 nip6 = mtod(m, struct ip6_hdr *); 365 nip6->ip6_src = oip6->ip6_src; 366 nip6->ip6_dst = oip6->ip6_dst; 367 368 in6_clearscope(&oip6->ip6_src); 369 in6_clearscope(&oip6->ip6_dst); 370 371 icmp6 = (struct icmp6_hdr *)(nip6 + 1); 372 icmp6->icmp6_type = type; 373 icmp6->icmp6_code = code; 374 icmp6->icmp6_pptr = htonl((u_int32_t)param); 375 376 /* 377 * icmp6_reflect() is designed to be in the input path. 378 * icmp6_error() can be called from both input and output path, 379 * and if we are in output path rcvif could contain bogus value. 380 * clear m->m_pkthdr.rcvif for safety, we should have enough scope 381 * information in ip header (nip6). 382 */ 383 m->m_pkthdr.rcvif = NULL; 384 385 icmp6stat.icp6s_outhist[type]++; 386 icmp6_reflect(m, sizeof(struct ip6_hdr)); /* header order: IPv6 - ICMPv6 */ 387 388 return; 389 390 freeit: 391 /* 392 * If we can't tell whether or not we can generate ICMP6, free it. 393 */ 394 m_freem(m); 395 } 396 397 /* 398 * Process a received ICMP6 message. 399 */ 400 int 401 icmp6_input(mp, offp, proto) 402 struct mbuf **mp; 403 int *offp, proto; 404 { 405 struct mbuf *m = *mp, *n; 406 struct ip6_hdr *ip6, *nip6; 407 struct icmp6_hdr *icmp6, *nicmp6; 408 int off = *offp; 409 int icmp6len = m->m_pkthdr.len - *offp; 410 int code, sum, noff; 411 412 #ifndef PULLDOWN_TEST 413 IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_hdr), IPPROTO_DONE); 414 /* m might change if M_LOOP. So, call mtod after this */ 415 #endif 416 417 /* 418 * Locate icmp6 structure in mbuf, and check 419 * that not corrupted and of at least minimum length 420 */ 421 422 ip6 = mtod(m, struct ip6_hdr *); 423 if (icmp6len < sizeof(struct icmp6_hdr)) { 424 icmp6stat.icp6s_tooshort++; 425 goto freeit; 426 } 427 428 /* 429 * calculate the checksum 430 */ 431 #ifndef PULLDOWN_TEST 432 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off); 433 #else 434 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 435 if (icmp6 == NULL) { 436 icmp6stat.icp6s_tooshort++; 437 return IPPROTO_DONE; 438 } 439 #endif 440 code = icmp6->icmp6_code; 441 442 if ((sum = in6_cksum(m, IPPROTO_ICMPV6, off, icmp6len)) != 0) { 443 nd6log((LOG_ERR, 444 "ICMP6 checksum error(%d|%x) %s\n", 445 icmp6->icmp6_type, sum, ip6_sprintf(&ip6->ip6_src))); 446 icmp6stat.icp6s_checksum++; 447 goto freeit; 448 } 449 450 if (faithprefix_p != NULL && (*faithprefix_p)(&ip6->ip6_dst)) { 451 /* 452 * Deliver very specific ICMP6 type only. 453 * This is important to deliver TOOBIG. Otherwise PMTUD 454 * will not work. 455 */ 456 switch (icmp6->icmp6_type) { 457 case ICMP6_DST_UNREACH: 458 case ICMP6_PACKET_TOO_BIG: 459 case ICMP6_TIME_EXCEEDED: 460 break; 461 default: 462 goto freeit; 463 } 464 } 465 466 icmp6stat.icp6s_inhist[icmp6->icmp6_type]++; 467 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_msg); 468 if (icmp6->icmp6_type < ICMP6_INFOMSG_MASK) 469 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_error); 470 471 switch (icmp6->icmp6_type) { 472 case ICMP6_DST_UNREACH: 473 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_dstunreach); 474 switch (code) { 475 case ICMP6_DST_UNREACH_NOROUTE: 476 code = PRC_UNREACH_NET; 477 break; 478 case ICMP6_DST_UNREACH_ADMIN: 479 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_adminprohib); 480 code = PRC_UNREACH_PROTOCOL; /* is this a good code? */ 481 break; 482 case ICMP6_DST_UNREACH_ADDR: 483 code = PRC_HOSTDEAD; 484 break; 485 case ICMP6_DST_UNREACH_BEYONDSCOPE: 486 /* I mean "source address was incorrect." */ 487 code = PRC_PARAMPROB; 488 break; 489 case ICMP6_DST_UNREACH_NOPORT: 490 code = PRC_UNREACH_PORT; 491 break; 492 default: 493 goto badcode; 494 } 495 goto deliver; 496 break; 497 498 case ICMP6_PACKET_TOO_BIG: 499 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_pkttoobig); 500 501 /* validation is made in icmp6_mtudisc_update */ 502 503 code = PRC_MSGSIZE; 504 505 /* 506 * Updating the path MTU will be done after examining 507 * intermediate extension headers. 508 */ 509 goto deliver; 510 break; 511 512 case ICMP6_TIME_EXCEEDED: 513 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_timeexceed); 514 switch (code) { 515 case ICMP6_TIME_EXCEED_TRANSIT: 516 code = PRC_TIMXCEED_INTRANS; 517 break; 518 case ICMP6_TIME_EXCEED_REASSEMBLY: 519 code = PRC_TIMXCEED_REASS; 520 break; 521 default: 522 goto badcode; 523 } 524 goto deliver; 525 break; 526 527 case ICMP6_PARAM_PROB: 528 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_paramprob); 529 switch (code) { 530 case ICMP6_PARAMPROB_NEXTHEADER: 531 code = PRC_UNREACH_PROTOCOL; 532 break; 533 case ICMP6_PARAMPROB_HEADER: 534 case ICMP6_PARAMPROB_OPTION: 535 code = PRC_PARAMPROB; 536 break; 537 default: 538 goto badcode; 539 } 540 goto deliver; 541 break; 542 543 case ICMP6_ECHO_REQUEST: 544 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echo); 545 if (code != 0) 546 goto badcode; 547 if ((n = m_copy(m, 0, M_COPYALL)) == NULL) { 548 /* Give up remote */ 549 break; 550 } 551 if ((n->m_flags & M_EXT) != 0 552 || n->m_len < off + sizeof(struct icmp6_hdr)) { 553 struct mbuf *n0 = n; 554 const int maxlen = sizeof(*nip6) + sizeof(*nicmp6); 555 int n0len; 556 557 MGETHDR(n, M_DONTWAIT, n0->m_type); 558 n0len = n0->m_pkthdr.len; /* save for use below */ 559 if (n) 560 M_MOVE_PKTHDR(n, n0); 561 if (n && maxlen >= MHLEN) { 562 MCLGET(n, M_DONTWAIT); 563 if ((n->m_flags & M_EXT) == 0) { 564 m_free(n); 565 n = NULL; 566 } 567 } 568 if (n == NULL) { 569 /* Give up remote */ 570 m_freem(n0); 571 break; 572 } 573 /* 574 * Copy IPv6 and ICMPv6 only. 575 */ 576 nip6 = mtod(n, struct ip6_hdr *); 577 bcopy(ip6, nip6, sizeof(struct ip6_hdr)); 578 nicmp6 = (struct icmp6_hdr *)(nip6 + 1); 579 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr)); 580 noff = sizeof(struct ip6_hdr); 581 /* new mbuf contains only ipv6+icmpv6 headers */ 582 n->m_len = noff + sizeof(struct icmp6_hdr); 583 /* 584 * Adjust mbuf. ip6_plen will be adjusted in 585 * ip6_output(). 586 */ 587 m_adj(n0, off + sizeof(struct icmp6_hdr)); 588 /* recalculate complete packet size */ 589 n->m_pkthdr.len = n0len + (noff - off); 590 n->m_next = n0; 591 } else { 592 nip6 = mtod(n, struct ip6_hdr *); 593 IP6_EXTHDR_GET(nicmp6, struct icmp6_hdr *, n, off, 594 sizeof(*nicmp6)); 595 noff = off; 596 } 597 nicmp6->icmp6_type = ICMP6_ECHO_REPLY; 598 nicmp6->icmp6_code = 0; 599 if (n) { 600 icmp6stat.icp6s_reflect++; 601 icmp6stat.icp6s_outhist[ICMP6_ECHO_REPLY]++; 602 icmp6_reflect(n, noff); 603 } 604 break; 605 606 case ICMP6_ECHO_REPLY: 607 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echoreply); 608 if (code != 0) 609 goto badcode; 610 break; 611 612 case MLD_LISTENER_QUERY: 613 case MLD_LISTENER_REPORT: 614 if (icmp6len < sizeof(struct mld_hdr)) 615 goto badlen; 616 if (icmp6->icmp6_type == MLD_LISTENER_QUERY) /* XXX: ugly... */ 617 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldquery); 618 else 619 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldreport); 620 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 621 /* give up local */ 622 mld6_input(m, off); 623 m = NULL; 624 goto freeit; 625 } 626 mld6_input(n, off); 627 /* m stays. */ 628 break; 629 630 case MLD_LISTENER_DONE: 631 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mlddone); 632 if (icmp6len < sizeof(struct mld_hdr)) /* necessary? */ 633 goto badlen; 634 break; /* nothing to be done in kernel */ 635 636 case MLD_MTRACE_RESP: 637 case MLD_MTRACE: 638 /* XXX: these two are experimental. not officially defined. */ 639 /* XXX: per-interface statistics? */ 640 break; /* just pass it to applications */ 641 642 case ICMP6_WRUREQUEST: /* ICMP6_FQDN_QUERY */ 643 { 644 enum { WRU, FQDN } mode; 645 646 if (!icmp6_nodeinfo) 647 break; 648 649 if (icmp6len == sizeof(struct icmp6_hdr) + 4) 650 mode = WRU; 651 else if (icmp6len >= sizeof(struct icmp6_nodeinfo)) 652 mode = FQDN; 653 else 654 goto badlen; 655 656 #define hostnamelen strlen(hostname) 657 if (mode == FQDN) { 658 #ifndef PULLDOWN_TEST 659 IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_nodeinfo), 660 IPPROTO_DONE); 661 #endif 662 n = m_copy(m, 0, M_COPYALL); 663 if (n) 664 n = ni6_input(n, off); 665 /* XXX meaningless if n == NULL */ 666 noff = sizeof(struct ip6_hdr); 667 } else { 668 u_char *p; 669 int maxlen, maxhlen; 670 671 /* 672 * XXX: this combination of flags is pointless, 673 * but should we keep this for compatibility? 674 */ 675 if ((icmp6_nodeinfo & 5) != 5) 676 break; 677 678 if (code != 0) 679 goto badcode; 680 maxlen = sizeof(*nip6) + sizeof(*nicmp6) + 4; 681 if (maxlen >= MCLBYTES) { 682 /* Give up remote */ 683 break; 684 } 685 MGETHDR(n, M_DONTWAIT, m->m_type); 686 if (n && maxlen > MHLEN) { 687 MCLGET(n, M_DONTWAIT); 688 if ((n->m_flags & M_EXT) == 0) { 689 m_free(n); 690 n = NULL; 691 } 692 } 693 if (n && !m_dup_pkthdr(n, m, M_DONTWAIT)) { 694 /* 695 * Previous code did a blind M_COPY_PKTHDR 696 * and said "just for rcvif". If true, then 697 * we could tolerate the dup failing (due to 698 * the deep copy of the tag chain). For now 699 * be conservative and just fail. 700 */ 701 m_free(n); 702 n = NULL; 703 } 704 if (n == NULL) { 705 /* Give up remote */ 706 break; 707 } 708 n->m_pkthdr.rcvif = NULL; 709 n->m_len = 0; 710 maxhlen = M_TRAILINGSPACE(n) - maxlen; 711 if (maxhlen > hostnamelen) 712 maxhlen = hostnamelen; 713 /* 714 * Copy IPv6 and ICMPv6 only. 715 */ 716 nip6 = mtod(n, struct ip6_hdr *); 717 bcopy(ip6, nip6, sizeof(struct ip6_hdr)); 718 nicmp6 = (struct icmp6_hdr *)(nip6 + 1); 719 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr)); 720 p = (u_char *)(nicmp6 + 1); 721 bzero(p, 4); 722 bcopy(hostname, p + 4, maxhlen); /* meaningless TTL */ 723 noff = sizeof(struct ip6_hdr); 724 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) + 725 sizeof(struct icmp6_hdr) + 4 + maxhlen; 726 nicmp6->icmp6_type = ICMP6_WRUREPLY; 727 nicmp6->icmp6_code = 0; 728 } 729 #undef hostnamelen 730 if (n) { 731 icmp6stat.icp6s_reflect++; 732 icmp6stat.icp6s_outhist[ICMP6_WRUREPLY]++; 733 icmp6_reflect(n, noff); 734 } 735 break; 736 } 737 738 case ICMP6_WRUREPLY: 739 if (code != 0) 740 goto badcode; 741 break; 742 743 case ND_ROUTER_SOLICIT: 744 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routersolicit); 745 if (code != 0) 746 goto badcode; 747 if (icmp6len < sizeof(struct nd_router_solicit)) 748 goto badlen; 749 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 750 /* give up local */ 751 nd6_rs_input(m, off, icmp6len); 752 m = NULL; 753 goto freeit; 754 } 755 nd6_rs_input(n, off, icmp6len); 756 /* m stays. */ 757 break; 758 759 case ND_ROUTER_ADVERT: 760 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routeradvert); 761 if (code != 0) 762 goto badcode; 763 if (icmp6len < sizeof(struct nd_router_advert)) 764 goto badlen; 765 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 766 /* give up local */ 767 nd6_ra_input(m, off, icmp6len); 768 m = NULL; 769 goto freeit; 770 } 771 nd6_ra_input(n, off, icmp6len); 772 /* m stays. */ 773 break; 774 775 case ND_NEIGHBOR_SOLICIT: 776 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighborsolicit); 777 if (code != 0) 778 goto badcode; 779 if (icmp6len < sizeof(struct nd_neighbor_solicit)) 780 goto badlen; 781 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 782 /* give up local */ 783 nd6_ns_input(m, off, icmp6len); 784 m = NULL; 785 goto freeit; 786 } 787 nd6_ns_input(n, off, icmp6len); 788 /* m stays. */ 789 break; 790 791 case ND_NEIGHBOR_ADVERT: 792 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighboradvert); 793 if (code != 0) 794 goto badcode; 795 if (icmp6len < sizeof(struct nd_neighbor_advert)) 796 goto badlen; 797 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 798 /* give up local */ 799 nd6_na_input(m, off, icmp6len); 800 m = NULL; 801 goto freeit; 802 } 803 nd6_na_input(n, off, icmp6len); 804 /* m stays. */ 805 break; 806 807 case ND_REDIRECT: 808 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_redirect); 809 if (code != 0) 810 goto badcode; 811 if (icmp6len < sizeof(struct nd_redirect)) 812 goto badlen; 813 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 814 /* give up local */ 815 icmp6_redirect_input(m, off); 816 m = NULL; 817 goto freeit; 818 } 819 icmp6_redirect_input(n, off); 820 /* m stays. */ 821 break; 822 823 case ICMP6_ROUTER_RENUMBERING: 824 if (code != ICMP6_ROUTER_RENUMBERING_COMMAND && 825 code != ICMP6_ROUTER_RENUMBERING_RESULT) 826 goto badcode; 827 if (icmp6len < sizeof(struct icmp6_router_renum)) 828 goto badlen; 829 break; 830 831 default: 832 nd6log((LOG_DEBUG, 833 "icmp6_input: unknown type %d(src=%s, dst=%s, ifid=%d)\n", 834 icmp6->icmp6_type, ip6_sprintf(&ip6->ip6_src), 835 ip6_sprintf(&ip6->ip6_dst), 836 m->m_pkthdr.rcvif ? m->m_pkthdr.rcvif->if_index : 0)); 837 if (icmp6->icmp6_type < ICMP6_ECHO_REQUEST) { 838 /* ICMPv6 error: MUST deliver it by spec... */ 839 code = PRC_NCMDS; 840 /* deliver */ 841 } else { 842 /* ICMPv6 informational: MUST not deliver */ 843 break; 844 } 845 deliver: 846 if (icmp6_notify_error(&m, off, icmp6len, code)) { 847 /* In this case, m should've been freed. */ 848 return (IPPROTO_DONE); 849 } 850 break; 851 852 badcode: 853 icmp6stat.icp6s_badcode++; 854 break; 855 856 badlen: 857 icmp6stat.icp6s_badlen++; 858 break; 859 } 860 861 /* deliver the packet to appropriate sockets */ 862 icmp6_rip6_input(&m, *offp); 863 864 return IPPROTO_DONE; 865 866 freeit: 867 m_freem(m); 868 return IPPROTO_DONE; 869 } 870 871 static int 872 icmp6_notify_error(mp, off, icmp6len, code) 873 struct mbuf **mp; 874 int off, icmp6len, code; 875 { 876 struct mbuf *m = *mp; 877 struct icmp6_hdr *icmp6; 878 struct ip6_hdr *eip6; 879 u_int32_t notifymtu; 880 struct sockaddr_in6 icmp6src, icmp6dst; 881 882 if (icmp6len < sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr)) { 883 icmp6stat.icp6s_tooshort++; 884 goto freeit; 885 } 886 #ifndef PULLDOWN_TEST 887 IP6_EXTHDR_CHECK(m, off, 888 sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr), -1); 889 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 890 #else 891 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, 892 sizeof(*icmp6) + sizeof(struct ip6_hdr)); 893 if (icmp6 == NULL) { 894 icmp6stat.icp6s_tooshort++; 895 return (-1); 896 } 897 #endif 898 eip6 = (struct ip6_hdr *)(icmp6 + 1); 899 900 /* Detect the upper level protocol */ 901 { 902 void (*ctlfunc)(int, struct sockaddr *, void *); 903 u_int8_t nxt = eip6->ip6_nxt; 904 int eoff = off + sizeof(struct icmp6_hdr) + 905 sizeof(struct ip6_hdr); 906 struct ip6ctlparam ip6cp; 907 struct in6_addr *finaldst = NULL; 908 int icmp6type = icmp6->icmp6_type; 909 struct ip6_frag *fh; 910 struct ip6_rthdr *rth; 911 struct ip6_rthdr0 *rth0; 912 int rthlen; 913 914 while (1) { /* XXX: should avoid infinite loop explicitly? */ 915 struct ip6_ext *eh; 916 917 switch (nxt) { 918 case IPPROTO_HOPOPTS: 919 case IPPROTO_DSTOPTS: 920 case IPPROTO_AH: 921 #ifndef PULLDOWN_TEST 922 IP6_EXTHDR_CHECK(m, 0, 923 eoff + sizeof(struct ip6_ext), -1); 924 eh = (struct ip6_ext *)(mtod(m, caddr_t) + eoff); 925 #else 926 IP6_EXTHDR_GET(eh, struct ip6_ext *, m, 927 eoff, sizeof(*eh)); 928 if (eh == NULL) { 929 icmp6stat.icp6s_tooshort++; 930 return (-1); 931 } 932 #endif 933 934 if (nxt == IPPROTO_AH) 935 eoff += (eh->ip6e_len + 2) << 2; 936 else 937 eoff += (eh->ip6e_len + 1) << 3; 938 nxt = eh->ip6e_nxt; 939 break; 940 case IPPROTO_ROUTING: 941 /* 942 * When the erroneous packet contains a 943 * routing header, we should examine the 944 * header to determine the final destination. 945 * Otherwise, we can't properly update 946 * information that depends on the final 947 * destination (e.g. path MTU). 948 */ 949 #ifndef PULLDOWN_TEST 950 IP6_EXTHDR_CHECK(m, 0, eoff + sizeof(*rth), -1); 951 rth = (struct ip6_rthdr *) 952 (mtod(m, caddr_t) + eoff); 953 #else 954 IP6_EXTHDR_GET(rth, struct ip6_rthdr *, m, 955 eoff, sizeof(*rth)); 956 if (rth == NULL) { 957 icmp6stat.icp6s_tooshort++; 958 return (-1); 959 } 960 #endif 961 rthlen = (rth->ip6r_len + 1) << 3; 962 /* 963 * XXX: currently there is no 964 * officially defined type other 965 * than type-0. 966 * Note that if the segment left field 967 * is 0, all intermediate hops must 968 * have been passed. 969 */ 970 if (rth->ip6r_segleft && 971 rth->ip6r_type == IPV6_RTHDR_TYPE_0) { 972 int hops; 973 974 #ifndef PULLDOWN_TEST 975 IP6_EXTHDR_CHECK(m, 0, eoff + rthlen, -1); 976 rth0 = (struct ip6_rthdr0 *) 977 (mtod(m, caddr_t) + eoff); 978 #else 979 IP6_EXTHDR_GET(rth0, 980 struct ip6_rthdr0 *, m, 981 eoff, rthlen); 982 if (rth0 == NULL) { 983 icmp6stat.icp6s_tooshort++; 984 return (-1); 985 } 986 #endif 987 /* just ignore a bogus header */ 988 if ((rth0->ip6r0_len % 2) == 0 && 989 (hops = rth0->ip6r0_len/2)) 990 finaldst = (struct in6_addr *)(rth0 + 1) + (hops - 1); 991 } 992 eoff += rthlen; 993 nxt = rth->ip6r_nxt; 994 break; 995 case IPPROTO_FRAGMENT: 996 #ifndef PULLDOWN_TEST 997 IP6_EXTHDR_CHECK(m, 0, eoff + 998 sizeof(struct ip6_frag), -1); 999 fh = (struct ip6_frag *)(mtod(m, caddr_t) + 1000 eoff); 1001 #else 1002 IP6_EXTHDR_GET(fh, struct ip6_frag *, m, 1003 eoff, sizeof(*fh)); 1004 if (fh == NULL) { 1005 icmp6stat.icp6s_tooshort++; 1006 return (-1); 1007 } 1008 #endif 1009 /* 1010 * Data after a fragment header is meaningless 1011 * unless it is the first fragment, but 1012 * we'll go to the notify label for path MTU 1013 * discovery. 1014 */ 1015 if (fh->ip6f_offlg & IP6F_OFF_MASK) 1016 goto notify; 1017 1018 eoff += sizeof(struct ip6_frag); 1019 nxt = fh->ip6f_nxt; 1020 break; 1021 default: 1022 /* 1023 * This case includes ESP and the No Next 1024 * Header. In such cases going to the notify 1025 * label does not have any meaning 1026 * (i.e. ctlfunc will be NULL), but we go 1027 * anyway since we might have to update 1028 * path MTU information. 1029 */ 1030 goto notify; 1031 } 1032 } 1033 notify: 1034 #ifndef PULLDOWN_TEST 1035 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 1036 #else 1037 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, 1038 sizeof(*icmp6) + sizeof(struct ip6_hdr)); 1039 if (icmp6 == NULL) { 1040 icmp6stat.icp6s_tooshort++; 1041 return (-1); 1042 } 1043 #endif 1044 1045 /* 1046 * retrieve parameters from the inner IPv6 header, and convert 1047 * them into sockaddr structures. 1048 * XXX: there is no guarantee that the source or destination 1049 * addresses of the inner packet are in the same scope as 1050 * the addresses of the icmp packet. But there is no other 1051 * way to determine the zone. 1052 */ 1053 eip6 = (struct ip6_hdr *)(icmp6 + 1); 1054 1055 bzero(&icmp6dst, sizeof(icmp6dst)); 1056 icmp6dst.sin6_len = sizeof(struct sockaddr_in6); 1057 icmp6dst.sin6_family = AF_INET6; 1058 if (finaldst == NULL) 1059 icmp6dst.sin6_addr = eip6->ip6_dst; 1060 else 1061 icmp6dst.sin6_addr = *finaldst; 1062 if (in6_setscope(&icmp6dst.sin6_addr, m->m_pkthdr.rcvif, NULL)) 1063 goto freeit; 1064 bzero(&icmp6src, sizeof(icmp6src)); 1065 icmp6src.sin6_len = sizeof(struct sockaddr_in6); 1066 icmp6src.sin6_family = AF_INET6; 1067 icmp6src.sin6_addr = eip6->ip6_src; 1068 if (in6_setscope(&icmp6src.sin6_addr, m->m_pkthdr.rcvif, NULL)) 1069 goto freeit; 1070 icmp6src.sin6_flowinfo = 1071 (eip6->ip6_flow & IPV6_FLOWLABEL_MASK); 1072 1073 if (finaldst == NULL) 1074 finaldst = &eip6->ip6_dst; 1075 ip6cp.ip6c_m = m; 1076 ip6cp.ip6c_icmp6 = icmp6; 1077 ip6cp.ip6c_ip6 = (struct ip6_hdr *)(icmp6 + 1); 1078 ip6cp.ip6c_off = eoff; 1079 ip6cp.ip6c_finaldst = finaldst; 1080 ip6cp.ip6c_src = &icmp6src; 1081 ip6cp.ip6c_nxt = nxt; 1082 1083 if (icmp6type == ICMP6_PACKET_TOO_BIG) { 1084 notifymtu = ntohl(icmp6->icmp6_mtu); 1085 ip6cp.ip6c_cmdarg = (void *)¬ifymtu; 1086 icmp6_mtudisc_update(&ip6cp, 1); /*XXX*/ 1087 } 1088 1089 ctlfunc = (void (*)(int, struct sockaddr *, void *)) 1090 (inet6sw[ip6_protox[nxt]].pr_ctlinput); 1091 if (ctlfunc) { 1092 (void) (*ctlfunc)(code, (struct sockaddr *)&icmp6dst, 1093 &ip6cp); 1094 } 1095 } 1096 *mp = m; 1097 return (0); 1098 1099 freeit: 1100 m_freem(m); 1101 return (-1); 1102 } 1103 1104 void 1105 icmp6_mtudisc_update(ip6cp, validated) 1106 struct ip6ctlparam *ip6cp; 1107 int validated; 1108 { 1109 struct in6_addr *dst = ip6cp->ip6c_finaldst; 1110 struct icmp6_hdr *icmp6 = ip6cp->ip6c_icmp6; 1111 struct mbuf *m = ip6cp->ip6c_m; /* will be necessary for scope issue */ 1112 u_int mtu = ntohl(icmp6->icmp6_mtu); 1113 struct in_conninfo inc; 1114 1115 #if 0 1116 /* 1117 * RFC2460 section 5, last paragraph. 1118 * even though minimum link MTU for IPv6 is IPV6_MMTU, 1119 * we may see ICMPv6 too big with mtu < IPV6_MMTU 1120 * due to packet translator in the middle. 1121 * see ip6_output() and ip6_getpmtu() "alwaysfrag" case for 1122 * special handling. 1123 */ 1124 if (mtu < IPV6_MMTU) 1125 return; 1126 #endif 1127 1128 /* 1129 * we reject ICMPv6 too big with abnormally small value. 1130 * XXX what is the good definition of "abnormally small"? 1131 */ 1132 if (mtu < sizeof(struct ip6_hdr) + sizeof(struct ip6_frag) + 8) 1133 return; 1134 1135 if (!validated) 1136 return; 1137 1138 /* 1139 * In case the suggested mtu is less than IPV6_MMTU, we 1140 * only need to remember that it was for above mentioned 1141 * "alwaysfrag" case. 1142 * Try to be as close to the spec as possible. 1143 */ 1144 if (mtu < IPV6_MMTU) 1145 mtu = IPV6_MMTU - 8; 1146 1147 bzero(&inc, sizeof(inc)); 1148 inc.inc_flags = 1; /* IPv6 */ 1149 inc.inc6_faddr = *dst; 1150 if (in6_setscope(&inc.inc6_faddr, m->m_pkthdr.rcvif, NULL)) 1151 return; 1152 1153 if (mtu < tcp_maxmtu6(&inc)) { 1154 tcp_hc_updatemtu(&inc, mtu); 1155 icmp6stat.icp6s_pmtuchg++; 1156 } 1157 } 1158 1159 /* 1160 * Process a Node Information Query packet, based on 1161 * draft-ietf-ipngwg-icmp-name-lookups-07. 1162 * 1163 * Spec incompatibilities: 1164 * - IPv6 Subject address handling 1165 * - IPv4 Subject address handling support missing 1166 * - Proxy reply (answer even if it's not for me) 1167 * - joins NI group address at in6_ifattach() time only, does not cope 1168 * with hostname changes by sethostname(3) 1169 */ 1170 #define hostnamelen strlen(hostname) 1171 static struct mbuf * 1172 ni6_input(m, off) 1173 struct mbuf *m; 1174 int off; 1175 { 1176 struct icmp6_nodeinfo *ni6, *nni6; 1177 struct mbuf *n = NULL; 1178 u_int16_t qtype; 1179 int subjlen; 1180 int replylen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo); 1181 struct ni_reply_fqdn *fqdn; 1182 int addrs; /* for NI_QTYPE_NODEADDR */ 1183 struct ifnet *ifp = NULL; /* for NI_QTYPE_NODEADDR */ 1184 struct in6_addr in6_subj; /* subject address */ 1185 struct ip6_hdr *ip6; 1186 int oldfqdn = 0; /* if 1, return pascal string (03 draft) */ 1187 char *subj = NULL; 1188 struct in6_ifaddr *ia6 = NULL; 1189 1190 ip6 = mtod(m, struct ip6_hdr *); 1191 #ifndef PULLDOWN_TEST 1192 ni6 = (struct icmp6_nodeinfo *)(mtod(m, caddr_t) + off); 1193 #else 1194 IP6_EXTHDR_GET(ni6, struct icmp6_nodeinfo *, m, off, sizeof(*ni6)); 1195 if (ni6 == NULL) { 1196 /* m is already reclaimed */ 1197 return (NULL); 1198 } 1199 #endif 1200 1201 /* 1202 * Validate IPv6 source address. 1203 * The default configuration MUST be to refuse answering queries from 1204 * global-scope addresses according to RFC4602. 1205 * Notes: 1206 * - it's not very clear what "refuse" means; this implementation 1207 * simply drops it. 1208 * - it's not very easy to identify global-scope (unicast) addresses 1209 * since there are many prefixes for them. It should be safer 1210 * and in practice sufficient to check "all" but loopback and 1211 * link-local (note that site-local unicast was deprecated and 1212 * ULA is defined as global scope-wise) 1213 */ 1214 if ((icmp6_nodeinfo & ICMP6_NODEINFO_GLOBALOK) == 0 && 1215 !IN6_IS_ADDR_LOOPBACK(&ip6->ip6_src) && 1216 !IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_src)) 1217 goto bad; 1218 1219 /* 1220 * Validate IPv6 destination address. 1221 * 1222 * The Responder must discard the Query without further processing 1223 * unless it is one of the Responder's unicast or anycast addresses, or 1224 * a link-local scope multicast address which the Responder has joined. 1225 * [RFC4602, Section 5.] 1226 */ 1227 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 1228 if (!IN6_IS_ADDR_MC_LINKLOCAL(&ip6->ip6_dst)) 1229 goto bad; 1230 /* else it's a link-local multicast, fine */ 1231 } else { /* unicast or anycast */ 1232 if ((ia6 = ip6_getdstifaddr(m)) == NULL) 1233 goto bad; /* XXX impossible */ 1234 1235 if ((ia6->ia6_flags & IN6_IFF_TEMPORARY) && 1236 !(icmp6_nodeinfo & ICMP6_NODEINFO_TMPADDROK)) { 1237 nd6log((LOG_DEBUG, "ni6_input: ignore node info to " 1238 "a temporary address in %s:%d", 1239 __FILE__, __LINE__)); 1240 goto bad; 1241 } 1242 } 1243 1244 /* validate query Subject field. */ 1245 qtype = ntohs(ni6->ni_qtype); 1246 subjlen = m->m_pkthdr.len - off - sizeof(struct icmp6_nodeinfo); 1247 switch (qtype) { 1248 case NI_QTYPE_NOOP: 1249 case NI_QTYPE_SUPTYPES: 1250 /* 07 draft */ 1251 if (ni6->ni_code == ICMP6_NI_SUBJ_FQDN && subjlen == 0) 1252 break; 1253 /* FALLTHROUGH */ 1254 case NI_QTYPE_FQDN: 1255 case NI_QTYPE_NODEADDR: 1256 case NI_QTYPE_IPV4ADDR: 1257 switch (ni6->ni_code) { 1258 case ICMP6_NI_SUBJ_IPV6: 1259 #if ICMP6_NI_SUBJ_IPV6 != 0 1260 case 0: 1261 #endif 1262 /* 1263 * backward compatibility - try to accept 03 draft 1264 * format, where no Subject is present. 1265 */ 1266 if (qtype == NI_QTYPE_FQDN && ni6->ni_code == 0 && 1267 subjlen == 0) { 1268 oldfqdn++; 1269 break; 1270 } 1271 #if ICMP6_NI_SUBJ_IPV6 != 0 1272 if (ni6->ni_code != ICMP6_NI_SUBJ_IPV6) 1273 goto bad; 1274 #endif 1275 1276 if (subjlen != sizeof(struct in6_addr)) 1277 goto bad; 1278 1279 /* 1280 * Validate Subject address. 1281 * 1282 * Not sure what exactly "address belongs to the node" 1283 * means in the spec, is it just unicast, or what? 1284 * 1285 * At this moment we consider Subject address as 1286 * "belong to the node" if the Subject address equals 1287 * to the IPv6 destination address; validation for 1288 * IPv6 destination address should have done enough 1289 * check for us. 1290 * 1291 * We do not do proxy at this moment. 1292 */ 1293 /* m_pulldown instead of copy? */ 1294 m_copydata(m, off + sizeof(struct icmp6_nodeinfo), 1295 subjlen, (caddr_t)&in6_subj); 1296 if (in6_setscope(&in6_subj, m->m_pkthdr.rcvif, NULL)) 1297 goto bad; 1298 1299 subj = (char *)&in6_subj; 1300 if (IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, &in6_subj)) 1301 break; 1302 1303 /* 1304 * XXX if we are to allow other cases, we should really 1305 * be careful about scope here. 1306 * basically, we should disallow queries toward IPv6 1307 * destination X with subject Y, 1308 * if scope(X) > scope(Y). 1309 * if we allow scope(X) > scope(Y), it will result in 1310 * information leakage across scope boundary. 1311 */ 1312 goto bad; 1313 1314 case ICMP6_NI_SUBJ_FQDN: 1315 /* 1316 * Validate Subject name with gethostname(3). 1317 * 1318 * The behavior may need some debate, since: 1319 * - we are not sure if the node has FQDN as 1320 * hostname (returned by gethostname(3)). 1321 * - the code does wildcard match for truncated names. 1322 * however, we are not sure if we want to perform 1323 * wildcard match, if gethostname(3) side has 1324 * truncated hostname. 1325 */ 1326 n = ni6_nametodns(hostname, hostnamelen, 0); 1327 if (!n || n->m_next || n->m_len == 0) 1328 goto bad; 1329 IP6_EXTHDR_GET(subj, char *, m, 1330 off + sizeof(struct icmp6_nodeinfo), subjlen); 1331 if (subj == NULL) 1332 goto bad; 1333 if (!ni6_dnsmatch(subj, subjlen, mtod(n, const char *), 1334 n->m_len)) { 1335 goto bad; 1336 } 1337 m_freem(n); 1338 n = NULL; 1339 break; 1340 1341 case ICMP6_NI_SUBJ_IPV4: /* XXX: to be implemented? */ 1342 default: 1343 goto bad; 1344 } 1345 break; 1346 } 1347 1348 /* refuse based on configuration. XXX ICMP6_NI_REFUSED? */ 1349 switch (qtype) { 1350 case NI_QTYPE_FQDN: 1351 if ((icmp6_nodeinfo & ICMP6_NODEINFO_FQDNOK) == 0) 1352 goto bad; 1353 break; 1354 case NI_QTYPE_NODEADDR: 1355 case NI_QTYPE_IPV4ADDR: 1356 if ((icmp6_nodeinfo & ICMP6_NODEINFO_NODEADDROK) == 0) 1357 goto bad; 1358 break; 1359 } 1360 1361 /* guess reply length */ 1362 switch (qtype) { 1363 case NI_QTYPE_NOOP: 1364 break; /* no reply data */ 1365 case NI_QTYPE_SUPTYPES: 1366 replylen += sizeof(u_int32_t); 1367 break; 1368 case NI_QTYPE_FQDN: 1369 /* XXX will append an mbuf */ 1370 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1371 break; 1372 case NI_QTYPE_NODEADDR: 1373 addrs = ni6_addrs(ni6, m, &ifp, (struct in6_addr *)subj); 1374 if ((replylen += addrs * (sizeof(struct in6_addr) + 1375 sizeof(u_int32_t))) > MCLBYTES) 1376 replylen = MCLBYTES; /* XXX: will truncate pkt later */ 1377 break; 1378 case NI_QTYPE_IPV4ADDR: 1379 /* unsupported - should respond with unknown Qtype? */ 1380 break; 1381 default: 1382 /* 1383 * XXX: We must return a reply with the ICMP6 code 1384 * `unknown Qtype' in this case. However we regard the case 1385 * as an FQDN query for backward compatibility. 1386 * Older versions set a random value to this field, 1387 * so it rarely varies in the defined qtypes. 1388 * But the mechanism is not reliable... 1389 * maybe we should obsolete older versions. 1390 */ 1391 qtype = NI_QTYPE_FQDN; 1392 /* XXX will append an mbuf */ 1393 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1394 oldfqdn++; 1395 break; 1396 } 1397 1398 /* allocate an mbuf to reply. */ 1399 MGETHDR(n, M_DONTWAIT, m->m_type); 1400 if (n == NULL) { 1401 m_freem(m); 1402 return (NULL); 1403 } 1404 M_MOVE_PKTHDR(n, m); /* just for recvif */ 1405 if (replylen > MHLEN) { 1406 if (replylen > MCLBYTES) { 1407 /* 1408 * XXX: should we try to allocate more? But MCLBYTES 1409 * is probably much larger than IPV6_MMTU... 1410 */ 1411 goto bad; 1412 } 1413 MCLGET(n, M_DONTWAIT); 1414 if ((n->m_flags & M_EXT) == 0) { 1415 goto bad; 1416 } 1417 } 1418 n->m_pkthdr.len = n->m_len = replylen; 1419 1420 /* copy mbuf header and IPv6 + Node Information base headers */ 1421 bcopy(mtod(m, caddr_t), mtod(n, caddr_t), sizeof(struct ip6_hdr)); 1422 nni6 = (struct icmp6_nodeinfo *)(mtod(n, struct ip6_hdr *) + 1); 1423 bcopy((caddr_t)ni6, (caddr_t)nni6, sizeof(struct icmp6_nodeinfo)); 1424 1425 /* qtype dependent procedure */ 1426 switch (qtype) { 1427 case NI_QTYPE_NOOP: 1428 nni6->ni_code = ICMP6_NI_SUCCESS; 1429 nni6->ni_flags = 0; 1430 break; 1431 case NI_QTYPE_SUPTYPES: 1432 { 1433 u_int32_t v; 1434 nni6->ni_code = ICMP6_NI_SUCCESS; 1435 nni6->ni_flags = htons(0x0000); /* raw bitmap */ 1436 /* supports NOOP, SUPTYPES, FQDN, and NODEADDR */ 1437 v = (u_int32_t)htonl(0x0000000f); 1438 bcopy(&v, nni6 + 1, sizeof(u_int32_t)); 1439 break; 1440 } 1441 case NI_QTYPE_FQDN: 1442 nni6->ni_code = ICMP6_NI_SUCCESS; 1443 fqdn = (struct ni_reply_fqdn *)(mtod(n, caddr_t) + 1444 sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo)); 1445 nni6->ni_flags = 0; /* XXX: meaningless TTL */ 1446 fqdn->ni_fqdn_ttl = 0; /* ditto. */ 1447 /* 1448 * XXX do we really have FQDN in variable "hostname"? 1449 */ 1450 n->m_next = ni6_nametodns(hostname, hostnamelen, oldfqdn); 1451 if (n->m_next == NULL) 1452 goto bad; 1453 /* XXX we assume that n->m_next is not a chain */ 1454 if (n->m_next->m_next != NULL) 1455 goto bad; 1456 n->m_pkthdr.len += n->m_next->m_len; 1457 break; 1458 case NI_QTYPE_NODEADDR: 1459 { 1460 int lenlim, copied; 1461 1462 nni6->ni_code = ICMP6_NI_SUCCESS; 1463 n->m_pkthdr.len = n->m_len = 1464 sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo); 1465 lenlim = M_TRAILINGSPACE(n); 1466 copied = ni6_store_addrs(ni6, nni6, ifp, lenlim); 1467 /* XXX: reset mbuf length */ 1468 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) + 1469 sizeof(struct icmp6_nodeinfo) + copied; 1470 break; 1471 } 1472 default: 1473 break; /* XXX impossible! */ 1474 } 1475 1476 nni6->ni_type = ICMP6_NI_REPLY; 1477 m_freem(m); 1478 return (n); 1479 1480 bad: 1481 m_freem(m); 1482 if (n) 1483 m_freem(n); 1484 return (NULL); 1485 } 1486 #undef hostnamelen 1487 1488 /* 1489 * make a mbuf with DNS-encoded string. no compression support. 1490 * 1491 * XXX names with less than 2 dots (like "foo" or "foo.section") will be 1492 * treated as truncated name (two \0 at the end). this is a wild guess. 1493 */ 1494 static struct mbuf * 1495 ni6_nametodns(name, namelen, old) 1496 const char *name; 1497 int namelen; 1498 int old; /* return pascal string if non-zero */ 1499 { 1500 struct mbuf *m; 1501 char *cp, *ep; 1502 const char *p, *q; 1503 int i, len, nterm; 1504 1505 if (old) 1506 len = namelen + 1; 1507 else 1508 len = MCLBYTES; 1509 1510 /* because MAXHOSTNAMELEN is usually 256, we use cluster mbuf */ 1511 MGET(m, M_DONTWAIT, MT_DATA); 1512 if (m && len > MLEN) { 1513 MCLGET(m, M_DONTWAIT); 1514 if ((m->m_flags & M_EXT) == 0) 1515 goto fail; 1516 } 1517 if (!m) 1518 goto fail; 1519 m->m_next = NULL; 1520 1521 if (old) { 1522 m->m_len = len; 1523 *mtod(m, char *) = namelen; 1524 bcopy(name, mtod(m, char *) + 1, namelen); 1525 return m; 1526 } else { 1527 m->m_len = 0; 1528 cp = mtod(m, char *); 1529 ep = mtod(m, char *) + M_TRAILINGSPACE(m); 1530 1531 /* if not certain about my name, return empty buffer */ 1532 if (namelen == 0) 1533 return m; 1534 1535 /* 1536 * guess if it looks like shortened hostname, or FQDN. 1537 * shortened hostname needs two trailing "\0". 1538 */ 1539 i = 0; 1540 for (p = name; p < name + namelen; p++) { 1541 if (*p && *p == '.') 1542 i++; 1543 } 1544 if (i < 2) 1545 nterm = 2; 1546 else 1547 nterm = 1; 1548 1549 p = name; 1550 while (cp < ep && p < name + namelen) { 1551 i = 0; 1552 for (q = p; q < name + namelen && *q && *q != '.'; q++) 1553 i++; 1554 /* result does not fit into mbuf */ 1555 if (cp + i + 1 >= ep) 1556 goto fail; 1557 /* 1558 * DNS label length restriction, RFC1035 page 8. 1559 * "i == 0" case is included here to avoid returning 1560 * 0-length label on "foo..bar". 1561 */ 1562 if (i <= 0 || i >= 64) 1563 goto fail; 1564 *cp++ = i; 1565 bcopy(p, cp, i); 1566 cp += i; 1567 p = q; 1568 if (p < name + namelen && *p == '.') 1569 p++; 1570 } 1571 /* termination */ 1572 if (cp + nterm >= ep) 1573 goto fail; 1574 while (nterm-- > 0) 1575 *cp++ = '\0'; 1576 m->m_len = cp - mtod(m, char *); 1577 return m; 1578 } 1579 1580 panic("should not reach here"); 1581 /* NOTREACHED */ 1582 1583 fail: 1584 if (m) 1585 m_freem(m); 1586 return NULL; 1587 } 1588 1589 /* 1590 * check if two DNS-encoded string matches. takes care of truncated 1591 * form (with \0\0 at the end). no compression support. 1592 * XXX upper/lowercase match (see RFC2065) 1593 */ 1594 static int 1595 ni6_dnsmatch(a, alen, b, blen) 1596 const char *a; 1597 int alen; 1598 const char *b; 1599 int blen; 1600 { 1601 const char *a0, *b0; 1602 int l; 1603 1604 /* simplest case - need validation? */ 1605 if (alen == blen && bcmp(a, b, alen) == 0) 1606 return 1; 1607 1608 a0 = a; 1609 b0 = b; 1610 1611 /* termination is mandatory */ 1612 if (alen < 2 || blen < 2) 1613 return 0; 1614 if (a0[alen - 1] != '\0' || b0[blen - 1] != '\0') 1615 return 0; 1616 alen--; 1617 blen--; 1618 1619 while (a - a0 < alen && b - b0 < blen) { 1620 if (a - a0 + 1 > alen || b - b0 + 1 > blen) 1621 return 0; 1622 1623 if ((signed char)a[0] < 0 || (signed char)b[0] < 0) 1624 return 0; 1625 /* we don't support compression yet */ 1626 if (a[0] >= 64 || b[0] >= 64) 1627 return 0; 1628 1629 /* truncated case */ 1630 if (a[0] == 0 && a - a0 == alen - 1) 1631 return 1; 1632 if (b[0] == 0 && b - b0 == blen - 1) 1633 return 1; 1634 if (a[0] == 0 || b[0] == 0) 1635 return 0; 1636 1637 if (a[0] != b[0]) 1638 return 0; 1639 l = a[0]; 1640 if (a - a0 + 1 + l > alen || b - b0 + 1 + l > blen) 1641 return 0; 1642 if (bcmp(a + 1, b + 1, l) != 0) 1643 return 0; 1644 1645 a += 1 + l; 1646 b += 1 + l; 1647 } 1648 1649 if (a - a0 == alen && b - b0 == blen) 1650 return 1; 1651 else 1652 return 0; 1653 } 1654 1655 /* 1656 * calculate the number of addresses to be returned in the node info reply. 1657 */ 1658 static int 1659 ni6_addrs(ni6, m, ifpp, subj) 1660 struct icmp6_nodeinfo *ni6; 1661 struct mbuf *m; 1662 struct ifnet **ifpp; 1663 struct in6_addr *subj; 1664 { 1665 struct ifnet *ifp; 1666 struct in6_ifaddr *ifa6; 1667 struct ifaddr *ifa; 1668 int addrs = 0, addrsofif, iffound = 0; 1669 int niflags = ni6->ni_flags; 1670 1671 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0) { 1672 switch (ni6->ni_code) { 1673 case ICMP6_NI_SUBJ_IPV6: 1674 if (subj == NULL) /* must be impossible... */ 1675 return (0); 1676 break; 1677 default: 1678 /* 1679 * XXX: we only support IPv6 subject address for 1680 * this Qtype. 1681 */ 1682 return (0); 1683 } 1684 } 1685 1686 IFNET_RLOCK(); 1687 for (ifp = TAILQ_FIRST(&ifnet); ifp; ifp = TAILQ_NEXT(ifp, if_list)) { 1688 addrsofif = 0; 1689 TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list) { 1690 if (ifa->ifa_addr->sa_family != AF_INET6) 1691 continue; 1692 ifa6 = (struct in6_ifaddr *)ifa; 1693 1694 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0 && 1695 IN6_ARE_ADDR_EQUAL(subj, &ifa6->ia_addr.sin6_addr)) 1696 iffound = 1; 1697 1698 /* 1699 * IPv4-mapped addresses can only be returned by a 1700 * Node Information proxy, since they represent 1701 * addresses of IPv4-only nodes, which perforce do 1702 * not implement this protocol. 1703 * [icmp-name-lookups-07, Section 5.4] 1704 * So we don't support NI_NODEADDR_FLAG_COMPAT in 1705 * this function at this moment. 1706 */ 1707 1708 /* What do we have to do about ::1? */ 1709 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1710 case IPV6_ADDR_SCOPE_LINKLOCAL: 1711 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0) 1712 continue; 1713 break; 1714 case IPV6_ADDR_SCOPE_SITELOCAL: 1715 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0) 1716 continue; 1717 break; 1718 case IPV6_ADDR_SCOPE_GLOBAL: 1719 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0) 1720 continue; 1721 break; 1722 default: 1723 continue; 1724 } 1725 1726 /* 1727 * check if anycast is okay. 1728 * XXX: just experimental. not in the spec. 1729 */ 1730 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 && 1731 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0) 1732 continue; /* we need only unicast addresses */ 1733 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 1734 (icmp6_nodeinfo & ICMP6_NODEINFO_TMPADDROK) == 0) { 1735 continue; 1736 } 1737 addrsofif++; /* count the address */ 1738 } 1739 if (iffound) { 1740 *ifpp = ifp; 1741 IFNET_RUNLOCK(); 1742 return (addrsofif); 1743 } 1744 1745 addrs += addrsofif; 1746 } 1747 IFNET_RUNLOCK(); 1748 1749 return (addrs); 1750 } 1751 1752 static int 1753 ni6_store_addrs(ni6, nni6, ifp0, resid) 1754 struct icmp6_nodeinfo *ni6, *nni6; 1755 struct ifnet *ifp0; 1756 int resid; 1757 { 1758 struct ifnet *ifp = ifp0 ? ifp0 : TAILQ_FIRST(&ifnet); 1759 struct in6_ifaddr *ifa6; 1760 struct ifaddr *ifa; 1761 struct ifnet *ifp_dep = NULL; 1762 int copied = 0, allow_deprecated = 0; 1763 u_char *cp = (u_char *)(nni6 + 1); 1764 int niflags = ni6->ni_flags; 1765 u_int32_t ltime; 1766 1767 if (ifp0 == NULL && !(niflags & NI_NODEADDR_FLAG_ALL)) 1768 return (0); /* needless to copy */ 1769 1770 IFNET_RLOCK(); 1771 again: 1772 1773 for (; ifp; ifp = TAILQ_NEXT(ifp, if_list)) { 1774 for (ifa = ifp->if_addrlist.tqh_first; ifa; 1775 ifa = ifa->ifa_list.tqe_next) { 1776 if (ifa->ifa_addr->sa_family != AF_INET6) 1777 continue; 1778 ifa6 = (struct in6_ifaddr *)ifa; 1779 1780 if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) != 0 && 1781 allow_deprecated == 0) { 1782 /* 1783 * prefererred address should be put before 1784 * deprecated addresses. 1785 */ 1786 1787 /* record the interface for later search */ 1788 if (ifp_dep == NULL) 1789 ifp_dep = ifp; 1790 1791 continue; 1792 } else if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) == 0 && 1793 allow_deprecated != 0) 1794 continue; /* we now collect deprecated addrs */ 1795 1796 /* What do we have to do about ::1? */ 1797 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1798 case IPV6_ADDR_SCOPE_LINKLOCAL: 1799 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0) 1800 continue; 1801 break; 1802 case IPV6_ADDR_SCOPE_SITELOCAL: 1803 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0) 1804 continue; 1805 break; 1806 case IPV6_ADDR_SCOPE_GLOBAL: 1807 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0) 1808 continue; 1809 break; 1810 default: 1811 continue; 1812 } 1813 1814 /* 1815 * check if anycast is okay. 1816 * XXX: just experimental. not in the spec. 1817 */ 1818 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 && 1819 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0) 1820 continue; 1821 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 1822 (icmp6_nodeinfo & ICMP6_NODEINFO_TMPADDROK) == 0) { 1823 continue; 1824 } 1825 1826 /* now we can copy the address */ 1827 if (resid < sizeof(struct in6_addr) + 1828 sizeof(u_int32_t)) { 1829 /* 1830 * We give up much more copy. 1831 * Set the truncate flag and return. 1832 */ 1833 nni6->ni_flags |= NI_NODEADDR_FLAG_TRUNCATE; 1834 IFNET_RUNLOCK(); 1835 return (copied); 1836 } 1837 1838 /* 1839 * Set the TTL of the address. 1840 * The TTL value should be one of the following 1841 * according to the specification: 1842 * 1843 * 1. The remaining lifetime of a DHCP lease on the 1844 * address, or 1845 * 2. The remaining Valid Lifetime of a prefix from 1846 * which the address was derived through Stateless 1847 * Autoconfiguration. 1848 * 1849 * Note that we currently do not support stateful 1850 * address configuration by DHCPv6, so the former 1851 * case can't happen. 1852 */ 1853 if (ifa6->ia6_lifetime.ia6t_expire == 0) 1854 ltime = ND6_INFINITE_LIFETIME; 1855 else { 1856 if (ifa6->ia6_lifetime.ia6t_expire > 1857 time_second) 1858 ltime = htonl(ifa6->ia6_lifetime.ia6t_expire - time_second); 1859 else 1860 ltime = 0; 1861 } 1862 1863 bcopy(<ime, cp, sizeof(u_int32_t)); 1864 cp += sizeof(u_int32_t); 1865 1866 /* copy the address itself */ 1867 bcopy(&ifa6->ia_addr.sin6_addr, cp, 1868 sizeof(struct in6_addr)); 1869 in6_clearscope((struct in6_addr *)cp); /* XXX */ 1870 cp += sizeof(struct in6_addr); 1871 1872 resid -= (sizeof(struct in6_addr) + sizeof(u_int32_t)); 1873 copied += (sizeof(struct in6_addr) + sizeof(u_int32_t)); 1874 } 1875 if (ifp0) /* we need search only on the specified IF */ 1876 break; 1877 } 1878 1879 if (allow_deprecated == 0 && ifp_dep != NULL) { 1880 ifp = ifp_dep; 1881 allow_deprecated = 1; 1882 1883 goto again; 1884 } 1885 1886 IFNET_RUNLOCK(); 1887 1888 return (copied); 1889 } 1890 1891 /* 1892 * XXX almost dup'ed code with rip6_input. 1893 */ 1894 static int 1895 icmp6_rip6_input(mp, off) 1896 struct mbuf **mp; 1897 int off; 1898 { 1899 struct mbuf *m = *mp; 1900 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1901 struct in6pcb *in6p; 1902 struct in6pcb *last = NULL; 1903 struct sockaddr_in6 fromsa; 1904 struct icmp6_hdr *icmp6; 1905 struct mbuf *opts = NULL; 1906 1907 #ifndef PULLDOWN_TEST 1908 /* this is assumed to be safe. */ 1909 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off); 1910 #else 1911 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 1912 if (icmp6 == NULL) { 1913 /* m is already reclaimed */ 1914 return (IPPROTO_DONE); 1915 } 1916 #endif 1917 1918 /* 1919 * XXX: the address may have embedded scope zone ID, which should be 1920 * hidden from applications. 1921 */ 1922 bzero(&fromsa, sizeof(fromsa)); 1923 fromsa.sin6_family = AF_INET6; 1924 fromsa.sin6_len = sizeof(struct sockaddr_in6); 1925 fromsa.sin6_addr = ip6->ip6_src; 1926 if (sa6_recoverscope(&fromsa)) { 1927 m_freem(m); 1928 return (IPPROTO_DONE); 1929 } 1930 1931 INP_INFO_RLOCK(&ripcbinfo); 1932 LIST_FOREACH(in6p, &ripcb, inp_list) { 1933 INP_LOCK(in6p); 1934 if ((in6p->inp_vflag & INP_IPV6) == 0) { 1935 docontinue: 1936 INP_UNLOCK(in6p); 1937 continue; 1938 } 1939 if (in6p->in6p_ip6_nxt != IPPROTO_ICMPV6) 1940 goto docontinue; 1941 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr) && 1942 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr, &ip6->ip6_dst)) 1943 goto docontinue; 1944 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr) && 1945 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr, &ip6->ip6_src)) 1946 goto docontinue; 1947 if (in6p->in6p_icmp6filt 1948 && ICMP6_FILTER_WILLBLOCK(icmp6->icmp6_type, 1949 in6p->in6p_icmp6filt)) 1950 goto docontinue; 1951 if (last) { 1952 struct mbuf *n = NULL; 1953 1954 /* 1955 * Recent network drivers tend to allocate a single 1956 * mbuf cluster, rather than to make a couple of 1957 * mbufs without clusters. Also, since the IPv6 code 1958 * path tries to avoid m_pullup(), it is highly 1959 * probable that we still have an mbuf cluster here 1960 * even though the necessary length can be stored in an 1961 * mbuf's internal buffer. 1962 * Meanwhile, the default size of the receive socket 1963 * buffer for raw sockets is not so large. This means 1964 * the possibility of packet loss is relatively higher 1965 * than before. To avoid this scenario, we copy the 1966 * received data to a separate mbuf that does not use 1967 * a cluster, if possible. 1968 * XXX: it is better to copy the data after stripping 1969 * intermediate headers. 1970 */ 1971 if ((m->m_flags & M_EXT) && m->m_next == NULL && 1972 m->m_len <= MHLEN) { 1973 MGET(n, M_DONTWAIT, m->m_type); 1974 if (n != NULL) { 1975 if (m_dup_pkthdr(n, m, M_NOWAIT)) { 1976 bcopy(m->m_data, n->m_data, 1977 m->m_len); 1978 n->m_len = m->m_len; 1979 } else { 1980 m_free(n); 1981 n = NULL; 1982 } 1983 } 1984 } 1985 if (n != NULL || 1986 (n = m_copy(m, 0, (int)M_COPYALL)) != NULL) { 1987 if (last->in6p_flags & IN6P_CONTROLOPTS) 1988 ip6_savecontrol(last, n, &opts); 1989 /* strip intermediate headers */ 1990 m_adj(n, off); 1991 if (sbappendaddr(&last->in6p_socket->so_rcv, 1992 (struct sockaddr *)&fromsa, n, opts) 1993 == 0) { 1994 /* should notify about lost packet */ 1995 m_freem(n); 1996 if (opts) { 1997 m_freem(opts); 1998 } 1999 } else 2000 sorwakeup(last->in6p_socket); 2001 opts = NULL; 2002 } 2003 INP_UNLOCK(last); 2004 } 2005 last = in6p; 2006 } 2007 if (last) { 2008 if (last->in6p_flags & IN6P_CONTROLOPTS) 2009 ip6_savecontrol(last, m, &opts); 2010 /* strip intermediate headers */ 2011 m_adj(m, off); 2012 2013 /* avoid using mbuf clusters if possible (see above) */ 2014 if ((m->m_flags & M_EXT) && m->m_next == NULL && 2015 m->m_len <= MHLEN) { 2016 struct mbuf *n; 2017 2018 MGET(n, M_DONTWAIT, m->m_type); 2019 if (n != NULL) { 2020 if (m_dup_pkthdr(n, m, M_NOWAIT)) { 2021 bcopy(m->m_data, n->m_data, m->m_len); 2022 n->m_len = m->m_len; 2023 2024 m_freem(m); 2025 m = n; 2026 } else { 2027 m_freem(n); 2028 n = NULL; 2029 } 2030 } 2031 } 2032 if (sbappendaddr(&last->in6p_socket->so_rcv, 2033 (struct sockaddr *)&fromsa, m, opts) == 0) { 2034 m_freem(m); 2035 if (opts) 2036 m_freem(opts); 2037 } else 2038 sorwakeup(last->in6p_socket); 2039 INP_UNLOCK(last); 2040 } else { 2041 m_freem(m); 2042 ip6stat.ip6s_delivered--; 2043 } 2044 INP_INFO_RUNLOCK(&ripcbinfo); 2045 return IPPROTO_DONE; 2046 } 2047 2048 /* 2049 * Reflect the ip6 packet back to the source. 2050 * OFF points to the icmp6 header, counted from the top of the mbuf. 2051 */ 2052 void 2053 icmp6_reflect(m, off) 2054 struct mbuf *m; 2055 size_t off; 2056 { 2057 struct ip6_hdr *ip6; 2058 struct icmp6_hdr *icmp6; 2059 struct in6_ifaddr *ia; 2060 int plen; 2061 int type, code; 2062 struct ifnet *outif = NULL; 2063 struct in6_addr origdst, *src = NULL; 2064 2065 /* too short to reflect */ 2066 if (off < sizeof(struct ip6_hdr)) { 2067 nd6log((LOG_DEBUG, 2068 "sanity fail: off=%lx, sizeof(ip6)=%lx in %s:%d\n", 2069 (u_long)off, (u_long)sizeof(struct ip6_hdr), 2070 __FILE__, __LINE__)); 2071 goto bad; 2072 } 2073 2074 /* 2075 * If there are extra headers between IPv6 and ICMPv6, strip 2076 * off that header first. 2077 */ 2078 #ifdef DIAGNOSTIC 2079 if (sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) > MHLEN) 2080 panic("assumption failed in icmp6_reflect"); 2081 #endif 2082 if (off > sizeof(struct ip6_hdr)) { 2083 size_t l; 2084 struct ip6_hdr nip6; 2085 2086 l = off - sizeof(struct ip6_hdr); 2087 m_copydata(m, 0, sizeof(nip6), (caddr_t)&nip6); 2088 m_adj(m, l); 2089 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 2090 if (m->m_len < l) { 2091 if ((m = m_pullup(m, l)) == NULL) 2092 return; 2093 } 2094 bcopy((caddr_t)&nip6, mtod(m, caddr_t), sizeof(nip6)); 2095 } else /* off == sizeof(struct ip6_hdr) */ { 2096 size_t l; 2097 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 2098 if (m->m_len < l) { 2099 if ((m = m_pullup(m, l)) == NULL) 2100 return; 2101 } 2102 } 2103 plen = m->m_pkthdr.len - sizeof(struct ip6_hdr); 2104 ip6 = mtod(m, struct ip6_hdr *); 2105 ip6->ip6_nxt = IPPROTO_ICMPV6; 2106 icmp6 = (struct icmp6_hdr *)(ip6 + 1); 2107 type = icmp6->icmp6_type; /* keep type for statistics */ 2108 code = icmp6->icmp6_code; /* ditto. */ 2109 2110 origdst = ip6->ip6_dst; 2111 /* 2112 * ip6_input() drops a packet if its src is multicast. 2113 * So, the src is never multicast. 2114 */ 2115 ip6->ip6_dst = ip6->ip6_src; 2116 2117 /* 2118 * If the incoming packet was addressed directly to us (i.e. unicast), 2119 * use dst as the src for the reply. 2120 * The IN6_IFF_NOTREADY case should be VERY rare, but is possible 2121 * (for example) when we encounter an error while forwarding procedure 2122 * destined to a duplicated address of ours. 2123 * Note that ip6_getdstifaddr() may fail if we are in an error handling 2124 * procedure of an outgoing packet of our own, in which case we need 2125 * to search in the ifaddr list. 2126 */ 2127 if (!IN6_IS_ADDR_MULTICAST(&origdst)) { 2128 if ((ia = ip6_getdstifaddr(m))) { 2129 if (!(ia->ia6_flags & 2130 (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY))) 2131 src = &ia->ia_addr.sin6_addr; 2132 } else { 2133 struct sockaddr_in6 d; 2134 2135 bzero(&d, sizeof(d)); 2136 d.sin6_family = AF_INET6; 2137 d.sin6_len = sizeof(d); 2138 d.sin6_addr = origdst; 2139 ia = (struct in6_ifaddr *) 2140 ifa_ifwithaddr((struct sockaddr *)&d); 2141 if (ia && 2142 !(ia->ia6_flags & 2143 (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY))) { 2144 src = &ia->ia_addr.sin6_addr; 2145 } 2146 } 2147 } 2148 2149 if (src == NULL) { 2150 int e; 2151 struct sockaddr_in6 sin6; 2152 struct route_in6 ro; 2153 2154 /* 2155 * This case matches to multicasts, our anycast, or unicasts 2156 * that we do not own. Select a source address based on the 2157 * source address of the erroneous packet. 2158 */ 2159 bzero(&sin6, sizeof(sin6)); 2160 sin6.sin6_family = AF_INET6; 2161 sin6.sin6_len = sizeof(sin6); 2162 sin6.sin6_addr = ip6->ip6_dst; /* zone ID should be embedded */ 2163 2164 bzero(&ro, sizeof(ro)); 2165 src = in6_selectsrc(&sin6, NULL, NULL, &ro, NULL, &outif, &e); 2166 if (ro.ro_rt) 2167 RTFREE(ro.ro_rt); /* XXX: we could use this */ 2168 if (src == NULL) { 2169 nd6log((LOG_DEBUG, 2170 "icmp6_reflect: source can't be determined: " 2171 "dst=%s, error=%d\n", 2172 ip6_sprintf(&sin6.sin6_addr), e)); 2173 goto bad; 2174 } 2175 } 2176 2177 ip6->ip6_src = *src; 2178 ip6->ip6_flow = 0; 2179 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2180 ip6->ip6_vfc |= IPV6_VERSION; 2181 ip6->ip6_nxt = IPPROTO_ICMPV6; 2182 if (outif) 2183 ip6->ip6_hlim = ND_IFINFO(outif)->chlim; 2184 else if (m->m_pkthdr.rcvif) { 2185 /* XXX: This may not be the outgoing interface */ 2186 ip6->ip6_hlim = ND_IFINFO(m->m_pkthdr.rcvif)->chlim; 2187 } else 2188 ip6->ip6_hlim = ip6_defhlim; 2189 2190 icmp6->icmp6_cksum = 0; 2191 icmp6->icmp6_cksum = in6_cksum(m, IPPROTO_ICMPV6, 2192 sizeof(struct ip6_hdr), plen); 2193 2194 /* 2195 * XXX option handling 2196 */ 2197 2198 m->m_flags &= ~(M_BCAST|M_MCAST); 2199 2200 ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL); 2201 if (outif) 2202 icmp6_ifoutstat_inc(outif, type, code); 2203 2204 return; 2205 2206 bad: 2207 m_freem(m); 2208 return; 2209 } 2210 2211 void 2212 icmp6_fasttimo() 2213 { 2214 2215 return; 2216 } 2217 2218 static const char * 2219 icmp6_redirect_diag(src6, dst6, tgt6) 2220 struct in6_addr *src6; 2221 struct in6_addr *dst6; 2222 struct in6_addr *tgt6; 2223 { 2224 static char buf[1024]; 2225 snprintf(buf, sizeof(buf), "(src=%s dst=%s tgt=%s)", 2226 ip6_sprintf(src6), ip6_sprintf(dst6), ip6_sprintf(tgt6)); 2227 return buf; 2228 } 2229 2230 void 2231 icmp6_redirect_input(m, off) 2232 struct mbuf *m; 2233 int off; 2234 { 2235 struct ifnet *ifp = m->m_pkthdr.rcvif; 2236 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 2237 struct nd_redirect *nd_rd; 2238 int icmp6len = ntohs(ip6->ip6_plen); 2239 char *lladdr = NULL; 2240 int lladdrlen = 0; 2241 u_char *redirhdr = NULL; 2242 int redirhdrlen = 0; 2243 struct rtentry *rt = NULL; 2244 int is_router; 2245 int is_onlink; 2246 struct in6_addr src6 = ip6->ip6_src; 2247 struct in6_addr redtgt6; 2248 struct in6_addr reddst6; 2249 union nd_opts ndopts; 2250 2251 if (!m || !ifp) 2252 return; 2253 2254 /* XXX if we are router, we don't update route by icmp6 redirect */ 2255 if (ip6_forwarding) 2256 goto freeit; 2257 if (!icmp6_rediraccept) 2258 goto freeit; 2259 2260 #ifndef PULLDOWN_TEST 2261 IP6_EXTHDR_CHECK(m, off, icmp6len,); 2262 nd_rd = (struct nd_redirect *)((caddr_t)ip6 + off); 2263 #else 2264 IP6_EXTHDR_GET(nd_rd, struct nd_redirect *, m, off, icmp6len); 2265 if (nd_rd == NULL) { 2266 icmp6stat.icp6s_tooshort++; 2267 return; 2268 } 2269 #endif 2270 redtgt6 = nd_rd->nd_rd_target; 2271 reddst6 = nd_rd->nd_rd_dst; 2272 2273 if (in6_setscope(&redtgt6, m->m_pkthdr.rcvif, NULL) || 2274 in6_setscope(&reddst6, m->m_pkthdr.rcvif, NULL)) { 2275 goto freeit; 2276 } 2277 2278 /* validation */ 2279 if (!IN6_IS_ADDR_LINKLOCAL(&src6)) { 2280 nd6log((LOG_ERR, 2281 "ICMP6 redirect sent from %s rejected; " 2282 "must be from linklocal\n", 2283 ip6_sprintf(&src6))); 2284 goto bad; 2285 } 2286 if (ip6->ip6_hlim != 255) { 2287 nd6log((LOG_ERR, 2288 "ICMP6 redirect sent from %s rejected; " 2289 "hlim=%d (must be 255)\n", 2290 ip6_sprintf(&src6), ip6->ip6_hlim)); 2291 goto bad; 2292 } 2293 { 2294 /* ip6->ip6_src must be equal to gw for icmp6->icmp6_reddst */ 2295 struct sockaddr_in6 sin6; 2296 struct in6_addr *gw6; 2297 2298 bzero(&sin6, sizeof(sin6)); 2299 sin6.sin6_family = AF_INET6; 2300 sin6.sin6_len = sizeof(struct sockaddr_in6); 2301 bcopy(&reddst6, &sin6.sin6_addr, sizeof(reddst6)); 2302 rt = rtalloc1((struct sockaddr *)&sin6, 0, 0UL); 2303 if (rt) { 2304 if (rt->rt_gateway == NULL || 2305 rt->rt_gateway->sa_family != AF_INET6) { 2306 nd6log((LOG_ERR, 2307 "ICMP6 redirect rejected; no route " 2308 "with inet6 gateway found for redirect dst: %s\n", 2309 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2310 RTFREE_LOCKED(rt); 2311 goto bad; 2312 } 2313 2314 gw6 = &(((struct sockaddr_in6 *)rt->rt_gateway)->sin6_addr); 2315 if (bcmp(&src6, gw6, sizeof(struct in6_addr)) != 0) { 2316 nd6log((LOG_ERR, 2317 "ICMP6 redirect rejected; " 2318 "not equal to gw-for-src=%s (must be same): " 2319 "%s\n", 2320 ip6_sprintf(gw6), 2321 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2322 RTFREE_LOCKED(rt); 2323 goto bad; 2324 } 2325 } else { 2326 nd6log((LOG_ERR, 2327 "ICMP6 redirect rejected; " 2328 "no route found for redirect dst: %s\n", 2329 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2330 goto bad; 2331 } 2332 RTFREE_LOCKED(rt); 2333 rt = NULL; 2334 } 2335 if (IN6_IS_ADDR_MULTICAST(&reddst6)) { 2336 nd6log((LOG_ERR, 2337 "ICMP6 redirect rejected; " 2338 "redirect dst must be unicast: %s\n", 2339 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2340 goto bad; 2341 } 2342 2343 is_router = is_onlink = 0; 2344 if (IN6_IS_ADDR_LINKLOCAL(&redtgt6)) 2345 is_router = 1; /* router case */ 2346 if (bcmp(&redtgt6, &reddst6, sizeof(redtgt6)) == 0) 2347 is_onlink = 1; /* on-link destination case */ 2348 if (!is_router && !is_onlink) { 2349 nd6log((LOG_ERR, 2350 "ICMP6 redirect rejected; " 2351 "neither router case nor onlink case: %s\n", 2352 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2353 goto bad; 2354 } 2355 /* validation passed */ 2356 2357 icmp6len -= sizeof(*nd_rd); 2358 nd6_option_init(nd_rd + 1, icmp6len, &ndopts); 2359 if (nd6_options(&ndopts) < 0) { 2360 nd6log((LOG_INFO, "icmp6_redirect_input: " 2361 "invalid ND option, rejected: %s\n", 2362 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2363 /* nd6_options have incremented stats */ 2364 goto freeit; 2365 } 2366 2367 if (ndopts.nd_opts_tgt_lladdr) { 2368 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 2369 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 2370 } 2371 2372 if (ndopts.nd_opts_rh) { 2373 redirhdrlen = ndopts.nd_opts_rh->nd_opt_rh_len; 2374 redirhdr = (u_char *)(ndopts.nd_opts_rh + 1); /* xxx */ 2375 } 2376 2377 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 2378 nd6log((LOG_INFO, 2379 "icmp6_redirect_input: lladdrlen mismatch for %s " 2380 "(if %d, icmp6 packet %d): %s\n", 2381 ip6_sprintf(&redtgt6), ifp->if_addrlen, lladdrlen - 2, 2382 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2383 goto bad; 2384 } 2385 2386 /* RFC 2461 8.3 */ 2387 nd6_cache_lladdr(ifp, &redtgt6, lladdr, lladdrlen, ND_REDIRECT, 2388 is_onlink ? ND_REDIRECT_ONLINK : ND_REDIRECT_ROUTER); 2389 2390 if (!is_onlink) { /* better router case. perform rtredirect. */ 2391 /* perform rtredirect */ 2392 struct sockaddr_in6 sdst; 2393 struct sockaddr_in6 sgw; 2394 struct sockaddr_in6 ssrc; 2395 2396 bzero(&sdst, sizeof(sdst)); 2397 bzero(&sgw, sizeof(sgw)); 2398 bzero(&ssrc, sizeof(ssrc)); 2399 sdst.sin6_family = sgw.sin6_family = ssrc.sin6_family = AF_INET6; 2400 sdst.sin6_len = sgw.sin6_len = ssrc.sin6_len = 2401 sizeof(struct sockaddr_in6); 2402 bcopy(&redtgt6, &sgw.sin6_addr, sizeof(struct in6_addr)); 2403 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2404 bcopy(&src6, &ssrc.sin6_addr, sizeof(struct in6_addr)); 2405 rtredirect((struct sockaddr *)&sdst, (struct sockaddr *)&sgw, 2406 (struct sockaddr *)NULL, RTF_GATEWAY | RTF_HOST, 2407 (struct sockaddr *)&ssrc); 2408 } 2409 /* finally update cached route in each socket via pfctlinput */ 2410 { 2411 struct sockaddr_in6 sdst; 2412 2413 bzero(&sdst, sizeof(sdst)); 2414 sdst.sin6_family = AF_INET6; 2415 sdst.sin6_len = sizeof(struct sockaddr_in6); 2416 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2417 pfctlinput(PRC_REDIRECT_HOST, (struct sockaddr *)&sdst); 2418 #if defined(IPSEC) || defined(FAST_IPSEC) 2419 key_sa_routechange((struct sockaddr *)&sdst); 2420 #endif 2421 } 2422 2423 freeit: 2424 m_freem(m); 2425 return; 2426 2427 bad: 2428 icmp6stat.icp6s_badredirect++; 2429 m_freem(m); 2430 } 2431 2432 void 2433 icmp6_redirect_output(m0, rt) 2434 struct mbuf *m0; 2435 struct rtentry *rt; 2436 { 2437 struct ifnet *ifp; /* my outgoing interface */ 2438 struct in6_addr *ifp_ll6; 2439 struct in6_addr *router_ll6; 2440 struct ip6_hdr *sip6; /* m0 as struct ip6_hdr */ 2441 struct mbuf *m = NULL; /* newly allocated one */ 2442 struct ip6_hdr *ip6; /* m as struct ip6_hdr */ 2443 struct nd_redirect *nd_rd; 2444 size_t maxlen; 2445 u_char *p; 2446 struct ifnet *outif = NULL; 2447 struct sockaddr_in6 src_sa; 2448 2449 icmp6_errcount(&icmp6stat.icp6s_outerrhist, ND_REDIRECT, 0); 2450 2451 /* if we are not router, we don't send icmp6 redirect */ 2452 if (!ip6_forwarding) 2453 goto fail; 2454 2455 /* sanity check */ 2456 if (!m0 || !rt || !(rt->rt_flags & RTF_UP) || !(ifp = rt->rt_ifp)) 2457 goto fail; 2458 2459 /* 2460 * Address check: 2461 * the source address must identify a neighbor, and 2462 * the destination address must not be a multicast address 2463 * [RFC 2461, sec 8.2] 2464 */ 2465 sip6 = mtod(m0, struct ip6_hdr *); 2466 bzero(&src_sa, sizeof(src_sa)); 2467 src_sa.sin6_family = AF_INET6; 2468 src_sa.sin6_len = sizeof(src_sa); 2469 src_sa.sin6_addr = sip6->ip6_src; 2470 if (nd6_is_addr_neighbor(&src_sa, ifp) == 0) 2471 goto fail; 2472 if (IN6_IS_ADDR_MULTICAST(&sip6->ip6_dst)) 2473 goto fail; /* what should we do here? */ 2474 2475 /* rate limit */ 2476 if (icmp6_ratelimit(&sip6->ip6_src, ND_REDIRECT, 0)) 2477 goto fail; 2478 2479 /* 2480 * Since we are going to append up to 1280 bytes (= IPV6_MMTU), 2481 * we almost always ask for an mbuf cluster for simplicity. 2482 * (MHLEN < IPV6_MMTU is almost always true) 2483 */ 2484 #if IPV6_MMTU >= MCLBYTES 2485 # error assumption failed about IPV6_MMTU and MCLBYTES 2486 #endif 2487 MGETHDR(m, M_DONTWAIT, MT_HEADER); 2488 if (m && IPV6_MMTU >= MHLEN) 2489 MCLGET(m, M_DONTWAIT); 2490 if (!m) 2491 goto fail; 2492 m->m_pkthdr.rcvif = NULL; 2493 m->m_len = 0; 2494 maxlen = M_TRAILINGSPACE(m); 2495 maxlen = min(IPV6_MMTU, maxlen); 2496 /* just for safety */ 2497 if (maxlen < sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) + 2498 ((sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7)) { 2499 goto fail; 2500 } 2501 2502 { 2503 /* get ip6 linklocal address for ifp(my outgoing interface). */ 2504 struct in6_ifaddr *ia; 2505 if ((ia = in6ifa_ifpforlinklocal(ifp, 2506 IN6_IFF_NOTREADY| 2507 IN6_IFF_ANYCAST)) == NULL) 2508 goto fail; 2509 ifp_ll6 = &ia->ia_addr.sin6_addr; 2510 } 2511 2512 /* get ip6 linklocal address for the router. */ 2513 if (rt->rt_gateway && (rt->rt_flags & RTF_GATEWAY)) { 2514 struct sockaddr_in6 *sin6; 2515 sin6 = (struct sockaddr_in6 *)rt->rt_gateway; 2516 router_ll6 = &sin6->sin6_addr; 2517 if (!IN6_IS_ADDR_LINKLOCAL(router_ll6)) 2518 router_ll6 = (struct in6_addr *)NULL; 2519 } else 2520 router_ll6 = (struct in6_addr *)NULL; 2521 2522 /* ip6 */ 2523 ip6 = mtod(m, struct ip6_hdr *); 2524 ip6->ip6_flow = 0; 2525 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2526 ip6->ip6_vfc |= IPV6_VERSION; 2527 /* ip6->ip6_plen will be set later */ 2528 ip6->ip6_nxt = IPPROTO_ICMPV6; 2529 ip6->ip6_hlim = 255; 2530 /* ip6->ip6_src must be linklocal addr for my outgoing if. */ 2531 bcopy(ifp_ll6, &ip6->ip6_src, sizeof(struct in6_addr)); 2532 bcopy(&sip6->ip6_src, &ip6->ip6_dst, sizeof(struct in6_addr)); 2533 2534 /* ND Redirect */ 2535 nd_rd = (struct nd_redirect *)(ip6 + 1); 2536 nd_rd->nd_rd_type = ND_REDIRECT; 2537 nd_rd->nd_rd_code = 0; 2538 nd_rd->nd_rd_reserved = 0; 2539 if (rt->rt_flags & RTF_GATEWAY) { 2540 /* 2541 * nd_rd->nd_rd_target must be a link-local address in 2542 * better router cases. 2543 */ 2544 if (!router_ll6) 2545 goto fail; 2546 bcopy(router_ll6, &nd_rd->nd_rd_target, 2547 sizeof(nd_rd->nd_rd_target)); 2548 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2549 sizeof(nd_rd->nd_rd_dst)); 2550 } else { 2551 /* make sure redtgt == reddst */ 2552 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_target, 2553 sizeof(nd_rd->nd_rd_target)); 2554 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2555 sizeof(nd_rd->nd_rd_dst)); 2556 } 2557 2558 p = (u_char *)(nd_rd + 1); 2559 2560 if (!router_ll6) 2561 goto nolladdropt; 2562 2563 { 2564 /* target lladdr option */ 2565 struct rtentry *rt_router = NULL; 2566 int len; 2567 struct sockaddr_dl *sdl; 2568 struct nd_opt_hdr *nd_opt; 2569 char *lladdr; 2570 2571 rt_router = nd6_lookup(router_ll6, 0, ifp); 2572 if (!rt_router) 2573 goto nolladdropt; 2574 len = sizeof(*nd_opt) + ifp->if_addrlen; 2575 len = (len + 7) & ~7; /* round by 8 */ 2576 /* safety check */ 2577 if (len + (p - (u_char *)ip6) > maxlen) 2578 goto nolladdropt; 2579 if (!(rt_router->rt_flags & RTF_GATEWAY) && 2580 (rt_router->rt_flags & RTF_LLINFO) && 2581 (rt_router->rt_gateway->sa_family == AF_LINK) && 2582 (sdl = (struct sockaddr_dl *)rt_router->rt_gateway) && 2583 sdl->sdl_alen) { 2584 nd_opt = (struct nd_opt_hdr *)p; 2585 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 2586 nd_opt->nd_opt_len = len >> 3; 2587 lladdr = (char *)(nd_opt + 1); 2588 bcopy(LLADDR(sdl), lladdr, ifp->if_addrlen); 2589 p += len; 2590 } 2591 } 2592 nolladdropt:; 2593 2594 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2595 2596 /* just to be safe */ 2597 #ifdef M_DECRYPTED /*not openbsd*/ 2598 if (m0->m_flags & M_DECRYPTED) 2599 goto noredhdropt; 2600 #endif 2601 if (p - (u_char *)ip6 > maxlen) 2602 goto noredhdropt; 2603 2604 { 2605 /* redirected header option */ 2606 int len; 2607 struct nd_opt_rd_hdr *nd_opt_rh; 2608 2609 /* 2610 * compute the maximum size for icmp6 redirect header option. 2611 * XXX room for auth header? 2612 */ 2613 len = maxlen - (p - (u_char *)ip6); 2614 len &= ~7; 2615 2616 /* This is just for simplicity. */ 2617 if (m0->m_pkthdr.len != m0->m_len) { 2618 if (m0->m_next) { 2619 m_freem(m0->m_next); 2620 m0->m_next = NULL; 2621 } 2622 m0->m_pkthdr.len = m0->m_len; 2623 } 2624 2625 /* 2626 * Redirected header option spec (RFC2461 4.6.3) talks nothing 2627 * about padding/truncate rule for the original IP packet. 2628 * From the discussion on IPv6imp in Feb 1999, 2629 * the consensus was: 2630 * - "attach as much as possible" is the goal 2631 * - pad if not aligned (original size can be guessed by 2632 * original ip6 header) 2633 * Following code adds the padding if it is simple enough, 2634 * and truncates if not. 2635 */ 2636 if (m0->m_next || m0->m_pkthdr.len != m0->m_len) 2637 panic("assumption failed in %s:%d", __FILE__, 2638 __LINE__); 2639 2640 if (len - sizeof(*nd_opt_rh) < m0->m_pkthdr.len) { 2641 /* not enough room, truncate */ 2642 m0->m_pkthdr.len = m0->m_len = len - 2643 sizeof(*nd_opt_rh); 2644 } else { 2645 /* enough room, pad or truncate */ 2646 size_t extra; 2647 2648 extra = m0->m_pkthdr.len % 8; 2649 if (extra) { 2650 /* pad if easy enough, truncate if not */ 2651 if (8 - extra <= M_TRAILINGSPACE(m0)) { 2652 /* pad */ 2653 m0->m_len += (8 - extra); 2654 m0->m_pkthdr.len += (8 - extra); 2655 } else { 2656 /* truncate */ 2657 m0->m_pkthdr.len -= extra; 2658 m0->m_len -= extra; 2659 } 2660 } 2661 len = m0->m_pkthdr.len + sizeof(*nd_opt_rh); 2662 m0->m_pkthdr.len = m0->m_len = len - 2663 sizeof(*nd_opt_rh); 2664 } 2665 2666 nd_opt_rh = (struct nd_opt_rd_hdr *)p; 2667 bzero(nd_opt_rh, sizeof(*nd_opt_rh)); 2668 nd_opt_rh->nd_opt_rh_type = ND_OPT_REDIRECTED_HEADER; 2669 nd_opt_rh->nd_opt_rh_len = len >> 3; 2670 p += sizeof(*nd_opt_rh); 2671 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2672 2673 /* connect m0 to m */ 2674 m_tag_delete_chain(m0, NULL); 2675 m0->m_flags &= ~M_PKTHDR; 2676 m->m_next = m0; 2677 m->m_pkthdr.len = m->m_len + m0->m_len; 2678 m0 = NULL; 2679 } 2680 noredhdropt:; 2681 if (m0) { 2682 m_freem(m0); 2683 m0 = NULL; 2684 } 2685 2686 /* XXX: clear embedded link IDs in the inner header */ 2687 in6_clearscope(&sip6->ip6_src); 2688 in6_clearscope(&sip6->ip6_dst); 2689 in6_clearscope(&nd_rd->nd_rd_target); 2690 in6_clearscope(&nd_rd->nd_rd_dst); 2691 2692 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr)); 2693 2694 nd_rd->nd_rd_cksum = 0; 2695 nd_rd->nd_rd_cksum = in6_cksum(m, IPPROTO_ICMPV6, 2696 sizeof(*ip6), ntohs(ip6->ip6_plen)); 2697 2698 /* send the packet to outside... */ 2699 ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL); 2700 if (outif) { 2701 icmp6_ifstat_inc(outif, ifs6_out_msg); 2702 icmp6_ifstat_inc(outif, ifs6_out_redirect); 2703 } 2704 icmp6stat.icp6s_outhist[ND_REDIRECT]++; 2705 2706 return; 2707 2708 fail: 2709 if (m) 2710 m_freem(m); 2711 if (m0) 2712 m_freem(m0); 2713 } 2714 2715 /* 2716 * ICMPv6 socket option processing. 2717 */ 2718 int 2719 icmp6_ctloutput(so, sopt) 2720 struct socket *so; 2721 struct sockopt *sopt; 2722 { 2723 int error = 0; 2724 int optlen; 2725 struct inpcb *inp = sotoinpcb(so); 2726 int level, op, optname; 2727 2728 if (sopt) { 2729 level = sopt->sopt_level; 2730 op = sopt->sopt_dir; 2731 optname = sopt->sopt_name; 2732 optlen = sopt->sopt_valsize; 2733 } else 2734 level = op = optname = optlen = 0; 2735 2736 if (level != IPPROTO_ICMPV6) { 2737 return EINVAL; 2738 } 2739 2740 switch (op) { 2741 case PRCO_SETOPT: 2742 switch (optname) { 2743 case ICMP6_FILTER: 2744 { 2745 struct icmp6_filter *p; 2746 2747 if (optlen != sizeof(*p)) { 2748 error = EMSGSIZE; 2749 break; 2750 } 2751 if (inp->in6p_icmp6filt == NULL) { 2752 error = EINVAL; 2753 break; 2754 } 2755 error = sooptcopyin(sopt, inp->in6p_icmp6filt, optlen, 2756 optlen); 2757 break; 2758 } 2759 2760 default: 2761 error = ENOPROTOOPT; 2762 break; 2763 } 2764 break; 2765 2766 case PRCO_GETOPT: 2767 switch (optname) { 2768 case ICMP6_FILTER: 2769 { 2770 if (inp->in6p_icmp6filt == NULL) { 2771 error = EINVAL; 2772 break; 2773 } 2774 error = sooptcopyout(sopt, inp->in6p_icmp6filt, 2775 sizeof(struct icmp6_filter)); 2776 break; 2777 } 2778 2779 default: 2780 error = ENOPROTOOPT; 2781 break; 2782 } 2783 break; 2784 } 2785 2786 return (error); 2787 } 2788 2789 /* 2790 * Perform rate limit check. 2791 * Returns 0 if it is okay to send the icmp6 packet. 2792 * Returns 1 if the router SHOULD NOT send this icmp6 packet due to rate 2793 * limitation. 2794 * 2795 * XXX per-destination/type check necessary? 2796 */ 2797 static int 2798 icmp6_ratelimit(dst, type, code) 2799 const struct in6_addr *dst; /* not used at this moment */ 2800 const int type; /* not used at this moment */ 2801 const int code; /* not used at this moment */ 2802 { 2803 int ret; 2804 2805 ret = 0; /* okay to send */ 2806 2807 /* PPS limit */ 2808 if (!ppsratecheck(&icmp6errppslim_last, &icmp6errpps_count, 2809 icmp6errppslim)) { 2810 /* The packet is subject to rate limit */ 2811 ret++; 2812 } 2813 2814 return ret; 2815 }
Cache object: a080e821011dc659c208646c75960945
[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]