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 /* $FreeBSD: releng/6.1/sys/netinet6/icmp6.c 158179 2006-04-30 16:44:43Z cvs2svn $ */ 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> 113 114 extern struct domain inet6domain; 115 116 struct icmp6stat icmp6stat; 117 118 extern struct inpcbinfo ripcbinfo; 119 extern struct inpcbhead ripcb; 120 extern int icmp6errppslim; 121 static int icmp6errpps_count = 0; 122 static struct timeval icmp6errppslim_last; 123 extern int icmp6_nodeinfo; 124 125 static void icmp6_errcount __P((struct icmp6errstat *, int, int)); 126 static int icmp6_rip6_input __P((struct mbuf **, int)); 127 static int icmp6_ratelimit __P((const struct in6_addr *, const int, const int)); 128 static const char *icmp6_redirect_diag __P((struct in6_addr *, 129 struct in6_addr *, struct in6_addr *)); 130 static struct mbuf *ni6_input __P((struct mbuf *, int)); 131 static struct mbuf *ni6_nametodns __P((const char *, int, int)); 132 static int ni6_dnsmatch __P((const char *, int, const char *, int)); 133 static int ni6_addrs __P((struct icmp6_nodeinfo *, struct mbuf *, 134 struct ifnet **, struct in6_addr *)); 135 static int ni6_store_addrs __P((struct icmp6_nodeinfo *, struct icmp6_nodeinfo *, 136 struct ifnet *, int)); 137 static int icmp6_notify_error __P((struct mbuf **, int, int, int)); 138 139 140 void 141 icmp6_init() 142 { 143 mld6_init(); 144 } 145 146 static void 147 icmp6_errcount(stat, type, code) 148 struct icmp6errstat *stat; 149 int type, code; 150 { 151 switch (type) { 152 case ICMP6_DST_UNREACH: 153 switch (code) { 154 case ICMP6_DST_UNREACH_NOROUTE: 155 stat->icp6errs_dst_unreach_noroute++; 156 return; 157 case ICMP6_DST_UNREACH_ADMIN: 158 stat->icp6errs_dst_unreach_admin++; 159 return; 160 case ICMP6_DST_UNREACH_BEYONDSCOPE: 161 stat->icp6errs_dst_unreach_beyondscope++; 162 return; 163 case ICMP6_DST_UNREACH_ADDR: 164 stat->icp6errs_dst_unreach_addr++; 165 return; 166 case ICMP6_DST_UNREACH_NOPORT: 167 stat->icp6errs_dst_unreach_noport++; 168 return; 169 } 170 break; 171 case ICMP6_PACKET_TOO_BIG: 172 stat->icp6errs_packet_too_big++; 173 return; 174 case ICMP6_TIME_EXCEEDED: 175 switch (code) { 176 case ICMP6_TIME_EXCEED_TRANSIT: 177 stat->icp6errs_time_exceed_transit++; 178 return; 179 case ICMP6_TIME_EXCEED_REASSEMBLY: 180 stat->icp6errs_time_exceed_reassembly++; 181 return; 182 } 183 break; 184 case ICMP6_PARAM_PROB: 185 switch (code) { 186 case ICMP6_PARAMPROB_HEADER: 187 stat->icp6errs_paramprob_header++; 188 return; 189 case ICMP6_PARAMPROB_NEXTHEADER: 190 stat->icp6errs_paramprob_nextheader++; 191 return; 192 case ICMP6_PARAMPROB_OPTION: 193 stat->icp6errs_paramprob_option++; 194 return; 195 } 196 break; 197 case ND_REDIRECT: 198 stat->icp6errs_redirect++; 199 return; 200 } 201 stat->icp6errs_unknown++; 202 } 203 204 /* 205 * A wrapper function for icmp6_error() necessary when the erroneous packet 206 * may not contain enough scope zone information. 207 */ 208 void 209 icmp6_error2(m, type, code, param, ifp) 210 struct mbuf *m; 211 int type, code, param; 212 struct ifnet *ifp; 213 { 214 struct ip6_hdr *ip6; 215 216 if (ifp == NULL) 217 return; 218 219 #ifndef PULLDOWN_TEST 220 IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), ); 221 #else 222 if (m->m_len < sizeof(struct ip6_hdr)) { 223 m = m_pullup(m, sizeof(struct ip6_hdr)); 224 if (m == NULL) 225 return; 226 } 227 #endif 228 229 ip6 = mtod(m, struct ip6_hdr *); 230 231 if (in6_setscope(&ip6->ip6_src, ifp, NULL) != 0) 232 return; 233 if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0) 234 return; 235 236 icmp6_error(m, type, code, param); 237 } 238 239 /* 240 * Generate an error packet of type error in response to bad IP6 packet. 241 */ 242 void 243 icmp6_error(m, type, code, param) 244 struct mbuf *m; 245 int type, code, param; 246 { 247 struct ip6_hdr *oip6, *nip6; 248 struct icmp6_hdr *icmp6; 249 u_int preplen; 250 int off; 251 int nxt; 252 253 icmp6stat.icp6s_error++; 254 255 /* count per-type-code statistics */ 256 icmp6_errcount(&icmp6stat.icp6s_outerrhist, type, code); 257 258 #ifdef M_DECRYPTED /*not openbsd*/ 259 if (m->m_flags & M_DECRYPTED) { 260 icmp6stat.icp6s_canterror++; 261 goto freeit; 262 } 263 #endif 264 265 #ifndef PULLDOWN_TEST 266 IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), ); 267 #else 268 if (m->m_len < sizeof(struct ip6_hdr)) { 269 m = m_pullup(m, sizeof(struct ip6_hdr)); 270 if (m == NULL) 271 return; 272 } 273 #endif 274 oip6 = mtod(m, struct ip6_hdr *); 275 276 /* 277 * If the destination address of the erroneous packet is a multicast 278 * address, or the packet was sent using link-layer multicast, 279 * we should basically suppress sending an error (RFC 2463, Section 280 * 2.4). 281 * We have two exceptions (the item e.2 in that section): 282 * - the Pakcet Too Big message can be sent for path MTU discovery. 283 * - the Parameter Problem Message that can be allowed an icmp6 error 284 * in the option type field. This check has been done in 285 * ip6_unknown_opt(), so we can just check the type and code. 286 */ 287 if ((m->m_flags & (M_BCAST|M_MCAST) || 288 IN6_IS_ADDR_MULTICAST(&oip6->ip6_dst)) && 289 (type != ICMP6_PACKET_TOO_BIG && 290 (type != ICMP6_PARAM_PROB || 291 code != ICMP6_PARAMPROB_OPTION))) 292 goto freeit; 293 294 /* 295 * RFC 2463, 2.4 (e.5): source address check. 296 * XXX: the case of anycast source? 297 */ 298 if (IN6_IS_ADDR_UNSPECIFIED(&oip6->ip6_src) || 299 IN6_IS_ADDR_MULTICAST(&oip6->ip6_src)) 300 goto freeit; 301 302 /* 303 * If we are about to send ICMPv6 against ICMPv6 error/redirect, 304 * don't do it. 305 */ 306 nxt = -1; 307 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); 308 if (off >= 0 && nxt == IPPROTO_ICMPV6) { 309 struct icmp6_hdr *icp; 310 311 #ifndef PULLDOWN_TEST 312 IP6_EXTHDR_CHECK(m, 0, off + sizeof(struct icmp6_hdr), ); 313 icp = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 314 #else 315 IP6_EXTHDR_GET(icp, struct icmp6_hdr *, m, off, 316 sizeof(*icp)); 317 if (icp == NULL) { 318 icmp6stat.icp6s_tooshort++; 319 return; 320 } 321 #endif 322 if (icp->icmp6_type < ICMP6_ECHO_REQUEST || 323 icp->icmp6_type == ND_REDIRECT) { 324 /* 325 * ICMPv6 error 326 * Special case: for redirect (which is 327 * informational) we must not send icmp6 error. 328 */ 329 icmp6stat.icp6s_canterror++; 330 goto freeit; 331 } else { 332 /* ICMPv6 informational - send the error */ 333 } 334 } else { 335 /* non-ICMPv6 - send the error */ 336 } 337 338 oip6 = mtod(m, struct ip6_hdr *); /* adjust pointer */ 339 340 /* Finally, do rate limitation check. */ 341 if (icmp6_ratelimit(&oip6->ip6_src, type, code)) { 342 icmp6stat.icp6s_toofreq++; 343 goto freeit; 344 } 345 346 /* 347 * OK, ICMP6 can be generated. 348 */ 349 350 if (m->m_pkthdr.len >= ICMPV6_PLD_MAXLEN) 351 m_adj(m, ICMPV6_PLD_MAXLEN - m->m_pkthdr.len); 352 353 preplen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 354 M_PREPEND(m, preplen, M_DONTWAIT); 355 if (m && m->m_len < preplen) 356 m = m_pullup(m, preplen); 357 if (m == NULL) { 358 nd6log((LOG_DEBUG, "ENOBUFS in icmp6_error %d\n", __LINE__)); 359 return; 360 } 361 362 nip6 = mtod(m, struct ip6_hdr *); 363 nip6->ip6_src = oip6->ip6_src; 364 nip6->ip6_dst = oip6->ip6_dst; 365 366 in6_clearscope(&oip6->ip6_src); 367 in6_clearscope(&oip6->ip6_dst); 368 369 icmp6 = (struct icmp6_hdr *)(nip6 + 1); 370 icmp6->icmp6_type = type; 371 icmp6->icmp6_code = code; 372 icmp6->icmp6_pptr = htonl((u_int32_t)param); 373 374 /* 375 * icmp6_reflect() is designed to be in the input path. 376 * icmp6_error() can be called from both input and output path, 377 * and if we are in output path rcvif could contain bogus value. 378 * clear m->m_pkthdr.rcvif for safety, we should have enough scope 379 * information in ip header (nip6). 380 */ 381 m->m_pkthdr.rcvif = NULL; 382 383 icmp6stat.icp6s_outhist[type]++; 384 icmp6_reflect(m, sizeof(struct ip6_hdr)); /* header order: IPv6 - ICMPv6 */ 385 386 return; 387 388 freeit: 389 /* 390 * If we can't tell whether or not we can generate ICMP6, free it. 391 */ 392 m_freem(m); 393 } 394 395 /* 396 * Process a received ICMP6 message. 397 */ 398 int 399 icmp6_input(mp, offp, proto) 400 struct mbuf **mp; 401 int *offp, proto; 402 { 403 struct mbuf *m = *mp, *n; 404 struct ip6_hdr *ip6, *nip6; 405 struct icmp6_hdr *icmp6, *nicmp6; 406 int off = *offp; 407 int icmp6len = m->m_pkthdr.len - *offp; 408 int code, sum, noff; 409 410 #ifndef PULLDOWN_TEST 411 IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_hdr), IPPROTO_DONE); 412 /* m might change if M_LOOP. So, call mtod after this */ 413 #endif 414 415 /* 416 * Locate icmp6 structure in mbuf, and check 417 * that not corrupted and of at least minimum length 418 */ 419 420 ip6 = mtod(m, struct ip6_hdr *); 421 if (icmp6len < sizeof(struct icmp6_hdr)) { 422 icmp6stat.icp6s_tooshort++; 423 goto freeit; 424 } 425 426 /* 427 * calculate the checksum 428 */ 429 #ifndef PULLDOWN_TEST 430 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off); 431 #else 432 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 433 if (icmp6 == NULL) { 434 icmp6stat.icp6s_tooshort++; 435 return IPPROTO_DONE; 436 } 437 #endif 438 code = icmp6->icmp6_code; 439 440 if ((sum = in6_cksum(m, IPPROTO_ICMPV6, off, icmp6len)) != 0) { 441 nd6log((LOG_ERR, 442 "ICMP6 checksum error(%d|%x) %s\n", 443 icmp6->icmp6_type, sum, ip6_sprintf(&ip6->ip6_src))); 444 icmp6stat.icp6s_checksum++; 445 goto freeit; 446 } 447 448 if (faithprefix_p != NULL && (*faithprefix_p)(&ip6->ip6_dst)) { 449 /* 450 * Deliver very specific ICMP6 type only. 451 * This is important to deliver TOOBIG. Otherwise PMTUD 452 * will not work. 453 */ 454 switch (icmp6->icmp6_type) { 455 case ICMP6_DST_UNREACH: 456 case ICMP6_PACKET_TOO_BIG: 457 case ICMP6_TIME_EXCEEDED: 458 break; 459 default: 460 goto freeit; 461 } 462 } 463 464 icmp6stat.icp6s_inhist[icmp6->icmp6_type]++; 465 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_msg); 466 if (icmp6->icmp6_type < ICMP6_INFOMSG_MASK) 467 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_error); 468 469 switch (icmp6->icmp6_type) { 470 case ICMP6_DST_UNREACH: 471 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_dstunreach); 472 switch (code) { 473 case ICMP6_DST_UNREACH_NOROUTE: 474 code = PRC_UNREACH_NET; 475 break; 476 case ICMP6_DST_UNREACH_ADMIN: 477 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_adminprohib); 478 code = PRC_UNREACH_PROTOCOL; /* is this a good code? */ 479 break; 480 case ICMP6_DST_UNREACH_ADDR: 481 code = PRC_HOSTDEAD; 482 break; 483 case ICMP6_DST_UNREACH_BEYONDSCOPE: 484 /* I mean "source address was incorrect." */ 485 code = PRC_PARAMPROB; 486 break; 487 case ICMP6_DST_UNREACH_NOPORT: 488 code = PRC_UNREACH_PORT; 489 break; 490 default: 491 goto badcode; 492 } 493 goto deliver; 494 break; 495 496 case ICMP6_PACKET_TOO_BIG: 497 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_pkttoobig); 498 499 /* validation is made in icmp6_mtudisc_update */ 500 501 code = PRC_MSGSIZE; 502 503 /* 504 * Updating the path MTU will be done after examining 505 * intermediate extension headers. 506 */ 507 goto deliver; 508 break; 509 510 case ICMP6_TIME_EXCEEDED: 511 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_timeexceed); 512 switch (code) { 513 case ICMP6_TIME_EXCEED_TRANSIT: 514 code = PRC_TIMXCEED_INTRANS; 515 break; 516 case ICMP6_TIME_EXCEED_REASSEMBLY: 517 code = PRC_TIMXCEED_REASS; 518 break; 519 default: 520 goto badcode; 521 } 522 goto deliver; 523 break; 524 525 case ICMP6_PARAM_PROB: 526 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_paramprob); 527 switch (code) { 528 case ICMP6_PARAMPROB_NEXTHEADER: 529 code = PRC_UNREACH_PROTOCOL; 530 break; 531 case ICMP6_PARAMPROB_HEADER: 532 case ICMP6_PARAMPROB_OPTION: 533 code = PRC_PARAMPROB; 534 break; 535 default: 536 goto badcode; 537 } 538 goto deliver; 539 break; 540 541 case ICMP6_ECHO_REQUEST: 542 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echo); 543 if (code != 0) 544 goto badcode; 545 if ((n = m_copy(m, 0, M_COPYALL)) == NULL) { 546 /* Give up remote */ 547 break; 548 } 549 if ((n->m_flags & M_EXT) != 0 550 || n->m_len < off + sizeof(struct icmp6_hdr)) { 551 struct mbuf *n0 = n; 552 const int maxlen = sizeof(*nip6) + sizeof(*nicmp6); 553 int n0len; 554 555 MGETHDR(n, M_DONTWAIT, n0->m_type); 556 n0len = n0->m_pkthdr.len; /* save for use below */ 557 if (n) 558 M_MOVE_PKTHDR(n, n0); 559 if (n && maxlen >= MHLEN) { 560 MCLGET(n, M_DONTWAIT); 561 if ((n->m_flags & M_EXT) == 0) { 562 m_free(n); 563 n = NULL; 564 } 565 } 566 if (n == NULL) { 567 /* Give up remote */ 568 m_freem(n0); 569 break; 570 } 571 /* 572 * Copy IPv6 and ICMPv6 only. 573 */ 574 nip6 = mtod(n, struct ip6_hdr *); 575 bcopy(ip6, nip6, sizeof(struct ip6_hdr)); 576 nicmp6 = (struct icmp6_hdr *)(nip6 + 1); 577 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr)); 578 noff = sizeof(struct ip6_hdr); 579 /* new mbuf contains only ipv6+icmpv6 headers */ 580 n->m_len = noff + sizeof(struct icmp6_hdr); 581 /* 582 * Adjust mbuf. ip6_plen will be adjusted in 583 * ip6_output(). 584 */ 585 m_adj(n0, off + sizeof(struct icmp6_hdr)); 586 /* recalculate complete packet size */ 587 n->m_pkthdr.len = n0len + (noff - off); 588 n->m_next = n0; 589 } else { 590 nip6 = mtod(n, struct ip6_hdr *); 591 nicmp6 = (struct icmp6_hdr *)((caddr_t)nip6 + off); 592 noff = off; 593 } 594 nicmp6->icmp6_type = ICMP6_ECHO_REPLY; 595 nicmp6->icmp6_code = 0; 596 if (n) { 597 icmp6stat.icp6s_reflect++; 598 icmp6stat.icp6s_outhist[ICMP6_ECHO_REPLY]++; 599 icmp6_reflect(n, noff); 600 } 601 break; 602 603 case ICMP6_ECHO_REPLY: 604 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echoreply); 605 if (code != 0) 606 goto badcode; 607 break; 608 609 case MLD_LISTENER_QUERY: 610 case MLD_LISTENER_REPORT: 611 if (icmp6len < sizeof(struct mld_hdr)) 612 goto badlen; 613 if (icmp6->icmp6_type == MLD_LISTENER_QUERY) /* XXX: ugly... */ 614 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldquery); 615 else 616 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldreport); 617 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 618 /* give up local */ 619 mld6_input(m, off); 620 m = NULL; 621 goto freeit; 622 } 623 mld6_input(n, off); 624 /* m stays. */ 625 break; 626 627 case MLD_LISTENER_DONE: 628 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mlddone); 629 if (icmp6len < sizeof(struct mld_hdr)) /* necessary? */ 630 goto badlen; 631 break; /* nothing to be done in kernel */ 632 633 case MLD_MTRACE_RESP: 634 case MLD_MTRACE: 635 /* XXX: these two are experimental. not officially defined. */ 636 /* XXX: per-interface statistics? */ 637 break; /* just pass it to applications */ 638 639 case ICMP6_WRUREQUEST: /* ICMP6_FQDN_QUERY */ 640 { 641 enum { WRU, FQDN } mode; 642 643 if (!icmp6_nodeinfo) 644 break; 645 646 if (icmp6len == sizeof(struct icmp6_hdr) + 4) 647 mode = WRU; 648 else if (icmp6len >= sizeof(struct icmp6_nodeinfo)) 649 mode = FQDN; 650 else 651 goto badlen; 652 653 #define hostnamelen strlen(hostname) 654 if (mode == FQDN) { 655 #ifndef PULLDOWN_TEST 656 IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_nodeinfo), 657 IPPROTO_DONE); 658 #endif 659 n = m_copy(m, 0, M_COPYALL); 660 if (n) 661 n = ni6_input(n, off); 662 /* XXX meaningless if n == NULL */ 663 noff = sizeof(struct ip6_hdr); 664 } else { 665 u_char *p; 666 int maxlen, maxhlen; 667 668 if ((icmp6_nodeinfo & 5) != 5) 669 break; 670 671 if (code != 0) 672 goto badcode; 673 maxlen = sizeof(*nip6) + sizeof(*nicmp6) + 4; 674 if (maxlen >= MCLBYTES) { 675 /* Give up remote */ 676 break; 677 } 678 MGETHDR(n, M_DONTWAIT, m->m_type); 679 if (n && maxlen > MHLEN) { 680 MCLGET(n, M_DONTWAIT); 681 if ((n->m_flags & M_EXT) == 0) { 682 m_free(n); 683 n = NULL; 684 } 685 } 686 if (!m_dup_pkthdr(n, m, M_DONTWAIT)) { 687 /* 688 * Previous code did a blind M_COPY_PKTHDR 689 * and said "just for rcvif". If true, then 690 * we could tolerate the dup failing (due to 691 * the deep copy of the tag chain). For now 692 * be conservative and just fail. 693 */ 694 m_free(n); 695 n = NULL; 696 } 697 if (n == NULL) { 698 /* Give up remote */ 699 break; 700 } 701 n->m_pkthdr.rcvif = NULL; 702 n->m_len = 0; 703 maxhlen = M_TRAILINGSPACE(n) - maxlen; 704 if (maxhlen > hostnamelen) 705 maxhlen = hostnamelen; 706 /* 707 * Copy IPv6 and ICMPv6 only. 708 */ 709 nip6 = mtod(n, struct ip6_hdr *); 710 bcopy(ip6, nip6, sizeof(struct ip6_hdr)); 711 nicmp6 = (struct icmp6_hdr *)(nip6 + 1); 712 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr)); 713 p = (u_char *)(nicmp6 + 1); 714 bzero(p, 4); 715 bcopy(hostname, p + 4, maxhlen); /* meaningless TTL */ 716 noff = sizeof(struct ip6_hdr); 717 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) + 718 sizeof(struct icmp6_hdr) + 4 + maxhlen; 719 nicmp6->icmp6_type = ICMP6_WRUREPLY; 720 nicmp6->icmp6_code = 0; 721 } 722 #undef hostnamelen 723 if (n) { 724 icmp6stat.icp6s_reflect++; 725 icmp6stat.icp6s_outhist[ICMP6_WRUREPLY]++; 726 icmp6_reflect(n, noff); 727 } 728 break; 729 } 730 731 case ICMP6_WRUREPLY: 732 if (code != 0) 733 goto badcode; 734 break; 735 736 case ND_ROUTER_SOLICIT: 737 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routersolicit); 738 if (code != 0) 739 goto badcode; 740 if (icmp6len < sizeof(struct nd_router_solicit)) 741 goto badlen; 742 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 743 /* give up local */ 744 nd6_rs_input(m, off, icmp6len); 745 m = NULL; 746 goto freeit; 747 } 748 nd6_rs_input(n, off, icmp6len); 749 /* m stays. */ 750 break; 751 752 case ND_ROUTER_ADVERT: 753 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routeradvert); 754 if (code != 0) 755 goto badcode; 756 if (icmp6len < sizeof(struct nd_router_advert)) 757 goto badlen; 758 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 759 /* give up local */ 760 nd6_ra_input(m, off, icmp6len); 761 m = NULL; 762 goto freeit; 763 } 764 nd6_ra_input(n, off, icmp6len); 765 /* m stays. */ 766 break; 767 768 case ND_NEIGHBOR_SOLICIT: 769 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighborsolicit); 770 if (code != 0) 771 goto badcode; 772 if (icmp6len < sizeof(struct nd_neighbor_solicit)) 773 goto badlen; 774 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 775 /* give up local */ 776 nd6_ns_input(m, off, icmp6len); 777 m = NULL; 778 goto freeit; 779 } 780 nd6_ns_input(n, off, icmp6len); 781 /* m stays. */ 782 break; 783 784 case ND_NEIGHBOR_ADVERT: 785 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighboradvert); 786 if (code != 0) 787 goto badcode; 788 if (icmp6len < sizeof(struct nd_neighbor_advert)) 789 goto badlen; 790 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 791 /* give up local */ 792 nd6_na_input(m, off, icmp6len); 793 m = NULL; 794 goto freeit; 795 } 796 nd6_na_input(n, off, icmp6len); 797 /* m stays. */ 798 break; 799 800 case ND_REDIRECT: 801 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_redirect); 802 if (code != 0) 803 goto badcode; 804 if (icmp6len < sizeof(struct nd_redirect)) 805 goto badlen; 806 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 807 /* give up local */ 808 icmp6_redirect_input(m, off); 809 m = NULL; 810 goto freeit; 811 } 812 icmp6_redirect_input(n, off); 813 /* m stays. */ 814 break; 815 816 case ICMP6_ROUTER_RENUMBERING: 817 if (code != ICMP6_ROUTER_RENUMBERING_COMMAND && 818 code != ICMP6_ROUTER_RENUMBERING_RESULT) 819 goto badcode; 820 if (icmp6len < sizeof(struct icmp6_router_renum)) 821 goto badlen; 822 break; 823 824 default: 825 nd6log((LOG_DEBUG, 826 "icmp6_input: unknown type %d(src=%s, dst=%s, ifid=%d)\n", 827 icmp6->icmp6_type, ip6_sprintf(&ip6->ip6_src), 828 ip6_sprintf(&ip6->ip6_dst), 829 m->m_pkthdr.rcvif ? m->m_pkthdr.rcvif->if_index : 0)); 830 if (icmp6->icmp6_type < ICMP6_ECHO_REQUEST) { 831 /* ICMPv6 error: MUST deliver it by spec... */ 832 code = PRC_NCMDS; 833 /* deliver */ 834 } else { 835 /* ICMPv6 informational: MUST not deliver */ 836 break; 837 } 838 deliver: 839 if (icmp6_notify_error(&m, off, icmp6len, code)) { 840 /* In this case, m should've been freed. */ 841 return (IPPROTO_DONE); 842 } 843 break; 844 845 badcode: 846 icmp6stat.icp6s_badcode++; 847 break; 848 849 badlen: 850 icmp6stat.icp6s_badlen++; 851 break; 852 } 853 854 /* deliver the packet to appropriate sockets */ 855 icmp6_rip6_input(&m, *offp); 856 857 return IPPROTO_DONE; 858 859 freeit: 860 m_freem(m); 861 return IPPROTO_DONE; 862 } 863 864 static int 865 icmp6_notify_error(mp, off, icmp6len, code) 866 struct mbuf **mp; 867 int off, icmp6len, code; 868 { 869 struct mbuf *m = *mp; 870 struct icmp6_hdr *icmp6; 871 struct ip6_hdr *eip6; 872 u_int32_t notifymtu; 873 struct sockaddr_in6 icmp6src, icmp6dst; 874 875 if (icmp6len < sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr)) { 876 icmp6stat.icp6s_tooshort++; 877 goto freeit; 878 } 879 #ifndef PULLDOWN_TEST 880 IP6_EXTHDR_CHECK(m, off, 881 sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr), -1); 882 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 883 #else 884 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, 885 sizeof(*icmp6) + sizeof(struct ip6_hdr)); 886 if (icmp6 == NULL) { 887 icmp6stat.icp6s_tooshort++; 888 return (-1); 889 } 890 #endif 891 eip6 = (struct ip6_hdr *)(icmp6 + 1); 892 893 /* Detect the upper level protocol */ 894 { 895 void (*ctlfunc) __P((int, struct sockaddr *, void *)); 896 u_int8_t nxt = eip6->ip6_nxt; 897 int eoff = off + sizeof(struct icmp6_hdr) + 898 sizeof(struct ip6_hdr); 899 struct ip6ctlparam ip6cp; 900 struct in6_addr *finaldst = NULL; 901 int icmp6type = icmp6->icmp6_type; 902 struct ip6_frag *fh; 903 struct ip6_rthdr *rth; 904 struct ip6_rthdr0 *rth0; 905 int rthlen; 906 907 while (1) { /* XXX: should avoid infinite loop explicitly? */ 908 struct ip6_ext *eh; 909 910 switch (nxt) { 911 case IPPROTO_HOPOPTS: 912 case IPPROTO_DSTOPTS: 913 case IPPROTO_AH: 914 #ifndef PULLDOWN_TEST 915 IP6_EXTHDR_CHECK(m, 0, 916 eoff + sizeof(struct ip6_ext), -1); 917 eh = (struct ip6_ext *)(mtod(m, caddr_t) + eoff); 918 #else 919 IP6_EXTHDR_GET(eh, struct ip6_ext *, m, 920 eoff, sizeof(*eh)); 921 if (eh == NULL) { 922 icmp6stat.icp6s_tooshort++; 923 return (-1); 924 } 925 #endif 926 927 if (nxt == IPPROTO_AH) 928 eoff += (eh->ip6e_len + 2) << 2; 929 else 930 eoff += (eh->ip6e_len + 1) << 3; 931 nxt = eh->ip6e_nxt; 932 break; 933 case IPPROTO_ROUTING: 934 /* 935 * When the erroneous packet contains a 936 * routing header, we should examine the 937 * header to determine the final destination. 938 * Otherwise, we can't properly update 939 * information that depends on the final 940 * destination (e.g. path MTU). 941 */ 942 #ifndef PULLDOWN_TEST 943 IP6_EXTHDR_CHECK(m, 0, eoff + sizeof(*rth), -1); 944 rth = (struct ip6_rthdr *) 945 (mtod(m, caddr_t) + eoff); 946 #else 947 IP6_EXTHDR_GET(rth, struct ip6_rthdr *, m, 948 eoff, sizeof(*rth)); 949 if (rth == NULL) { 950 icmp6stat.icp6s_tooshort++; 951 return (-1); 952 } 953 #endif 954 rthlen = (rth->ip6r_len + 1) << 3; 955 /* 956 * XXX: currently there is no 957 * officially defined type other 958 * than type-0. 959 * Note that if the segment left field 960 * is 0, all intermediate hops must 961 * have been passed. 962 */ 963 if (rth->ip6r_segleft && 964 rth->ip6r_type == IPV6_RTHDR_TYPE_0) { 965 int hops; 966 967 #ifndef PULLDOWN_TEST 968 IP6_EXTHDR_CHECK(m, 0, eoff + rthlen, -1); 969 rth0 = (struct ip6_rthdr0 *) 970 (mtod(m, caddr_t) + eoff); 971 #else 972 IP6_EXTHDR_GET(rth0, 973 struct ip6_rthdr0 *, m, 974 eoff, rthlen); 975 if (rth0 == NULL) { 976 icmp6stat.icp6s_tooshort++; 977 return (-1); 978 } 979 #endif 980 /* just ignore a bogus header */ 981 if ((rth0->ip6r0_len % 2) == 0 && 982 (hops = rth0->ip6r0_len/2)) 983 finaldst = (struct in6_addr *)(rth0 + 1) + (hops - 1); 984 } 985 eoff += rthlen; 986 nxt = rth->ip6r_nxt; 987 break; 988 case IPPROTO_FRAGMENT: 989 #ifndef PULLDOWN_TEST 990 IP6_EXTHDR_CHECK(m, 0, eoff + 991 sizeof(struct ip6_frag), -1); 992 fh = (struct ip6_frag *)(mtod(m, caddr_t) + 993 eoff); 994 #else 995 IP6_EXTHDR_GET(fh, struct ip6_frag *, m, 996 eoff, sizeof(*fh)); 997 if (fh == NULL) { 998 icmp6stat.icp6s_tooshort++; 999 return (-1); 1000 } 1001 #endif 1002 /* 1003 * Data after a fragment header is meaningless 1004 * unless it is the first fragment, but 1005 * we'll go to the notify label for path MTU 1006 * discovery. 1007 */ 1008 if (fh->ip6f_offlg & IP6F_OFF_MASK) 1009 goto notify; 1010 1011 eoff += sizeof(struct ip6_frag); 1012 nxt = fh->ip6f_nxt; 1013 break; 1014 default: 1015 /* 1016 * This case includes ESP and the No Next 1017 * Header. In such cases going to the notify 1018 * label does not have any meaning 1019 * (i.e. ctlfunc will be NULL), but we go 1020 * anyway since we might have to update 1021 * path MTU information. 1022 */ 1023 goto notify; 1024 } 1025 } 1026 notify: 1027 #ifndef PULLDOWN_TEST 1028 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 1029 #else 1030 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, 1031 sizeof(*icmp6) + sizeof(struct ip6_hdr)); 1032 if (icmp6 == NULL) { 1033 icmp6stat.icp6s_tooshort++; 1034 return (-1); 1035 } 1036 #endif 1037 1038 /* 1039 * retrieve parameters from the inner IPv6 header, and convert 1040 * them into sockaddr structures. 1041 * XXX: there is no guarantee that the source or destination 1042 * addresses of the inner packet are in the same scope as 1043 * the addresses of the icmp packet. But there is no other 1044 * way to determine the zone. 1045 */ 1046 eip6 = (struct ip6_hdr *)(icmp6 + 1); 1047 1048 bzero(&icmp6dst, sizeof(icmp6dst)); 1049 icmp6dst.sin6_len = sizeof(struct sockaddr_in6); 1050 icmp6dst.sin6_family = AF_INET6; 1051 if (finaldst == NULL) 1052 icmp6dst.sin6_addr = eip6->ip6_dst; 1053 else 1054 icmp6dst.sin6_addr = *finaldst; 1055 if (in6_setscope(&icmp6dst.sin6_addr, m->m_pkthdr.rcvif, NULL)) 1056 goto freeit; 1057 bzero(&icmp6src, sizeof(icmp6src)); 1058 icmp6src.sin6_len = sizeof(struct sockaddr_in6); 1059 icmp6src.sin6_family = AF_INET6; 1060 icmp6src.sin6_addr = eip6->ip6_src; 1061 if (in6_setscope(&icmp6src.sin6_addr, m->m_pkthdr.rcvif, NULL)) 1062 goto freeit; 1063 icmp6src.sin6_flowinfo = 1064 (eip6->ip6_flow & IPV6_FLOWLABEL_MASK); 1065 1066 if (finaldst == NULL) 1067 finaldst = &eip6->ip6_dst; 1068 ip6cp.ip6c_m = m; 1069 ip6cp.ip6c_icmp6 = icmp6; 1070 ip6cp.ip6c_ip6 = (struct ip6_hdr *)(icmp6 + 1); 1071 ip6cp.ip6c_off = eoff; 1072 ip6cp.ip6c_finaldst = finaldst; 1073 ip6cp.ip6c_src = &icmp6src; 1074 ip6cp.ip6c_nxt = nxt; 1075 1076 if (icmp6type == ICMP6_PACKET_TOO_BIG) { 1077 notifymtu = ntohl(icmp6->icmp6_mtu); 1078 ip6cp.ip6c_cmdarg = (void *)¬ifymtu; 1079 icmp6_mtudisc_update(&ip6cp, 1); /*XXX*/ 1080 } 1081 1082 ctlfunc = (void (*) __P((int, struct sockaddr *, void *))) 1083 (inet6sw[ip6_protox[nxt]].pr_ctlinput); 1084 if (ctlfunc) { 1085 (void) (*ctlfunc)(code, (struct sockaddr *)&icmp6dst, 1086 &ip6cp); 1087 } 1088 } 1089 *mp = m; 1090 return (0); 1091 1092 freeit: 1093 m_freem(m); 1094 return (-1); 1095 } 1096 1097 void 1098 icmp6_mtudisc_update(ip6cp, validated) 1099 struct ip6ctlparam *ip6cp; 1100 int validated; 1101 { 1102 struct in6_addr *dst = ip6cp->ip6c_finaldst; 1103 struct icmp6_hdr *icmp6 = ip6cp->ip6c_icmp6; 1104 struct mbuf *m = ip6cp->ip6c_m; /* will be necessary for scope issue */ 1105 u_int mtu = ntohl(icmp6->icmp6_mtu); 1106 struct in_conninfo inc; 1107 1108 #if 0 1109 /* 1110 * RFC2460 section 5, last paragraph. 1111 * even though minimum link MTU for IPv6 is IPV6_MMTU, 1112 * we may see ICMPv6 too big with mtu < IPV6_MMTU 1113 * due to packet translator in the middle. 1114 * see ip6_output() and ip6_getpmtu() "alwaysfrag" case for 1115 * special handling. 1116 */ 1117 if (mtu < IPV6_MMTU) 1118 return; 1119 #endif 1120 1121 /* 1122 * we reject ICMPv6 too big with abnormally small value. 1123 * XXX what is the good definition of "abnormally small"? 1124 */ 1125 if (mtu < sizeof(struct ip6_hdr) + sizeof(struct ip6_frag) + 8) 1126 return; 1127 1128 if (!validated) 1129 return; 1130 1131 bzero(&inc, sizeof(inc)); 1132 inc.inc_flags = 1; /* IPv6 */ 1133 inc.inc6_faddr = *dst; 1134 if (in6_setscope(&inc.inc6_faddr, m->m_pkthdr.rcvif, NULL)) 1135 return; 1136 1137 if (mtu < tcp_maxmtu6(&inc)) { 1138 tcp_hc_updatemtu(&inc, mtu); 1139 icmp6stat.icp6s_pmtuchg++; 1140 } 1141 } 1142 1143 /* 1144 * Process a Node Information Query packet, based on 1145 * draft-ietf-ipngwg-icmp-name-lookups-07. 1146 * 1147 * Spec incompatibilities: 1148 * - IPv6 Subject address handling 1149 * - IPv4 Subject address handling support missing 1150 * - Proxy reply (answer even if it's not for me) 1151 * - joins NI group address at in6_ifattach() time only, does not cope 1152 * with hostname changes by sethostname(3) 1153 */ 1154 #define hostnamelen strlen(hostname) 1155 static struct mbuf * 1156 ni6_input(m, off) 1157 struct mbuf *m; 1158 int off; 1159 { 1160 struct icmp6_nodeinfo *ni6, *nni6; 1161 struct mbuf *n = NULL; 1162 u_int16_t qtype; 1163 int subjlen; 1164 int replylen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo); 1165 struct ni_reply_fqdn *fqdn; 1166 int addrs; /* for NI_QTYPE_NODEADDR */ 1167 struct ifnet *ifp = NULL; /* for NI_QTYPE_NODEADDR */ 1168 struct in6_addr in6_subj; /* subject address */ 1169 struct ip6_hdr *ip6; 1170 int oldfqdn = 0; /* if 1, return pascal string (03 draft) */ 1171 char *subj = NULL; 1172 struct in6_ifaddr *ia6 = NULL; 1173 1174 ip6 = mtod(m, struct ip6_hdr *); 1175 #ifndef PULLDOWN_TEST 1176 ni6 = (struct icmp6_nodeinfo *)(mtod(m, caddr_t) + off); 1177 #else 1178 IP6_EXTHDR_GET(ni6, struct icmp6_nodeinfo *, m, off, sizeof(*ni6)); 1179 if (ni6 == NULL) { 1180 /* m is already reclaimed */ 1181 return (NULL); 1182 } 1183 #endif 1184 1185 /* 1186 * Validate IPv6 destination address. 1187 * 1188 * The Responder must discard the Query without further processing 1189 * unless it is one of the Responder's unicast or anycast addresses, or 1190 * a link-local scope multicast address which the Responder has joined. 1191 * [icmp-name-lookups-08, Section 4.] 1192 */ 1193 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 1194 if (!IN6_IS_ADDR_MC_LINKLOCAL(&ip6->ip6_dst)) 1195 goto bad; 1196 /* else it's a link-local multicast, fine */ 1197 } else { /* unicast or anycast */ 1198 if ((ia6 = ip6_getdstifaddr(m)) == NULL) 1199 goto bad; /* XXX impossible */ 1200 1201 if ((ia6->ia6_flags & IN6_IFF_TEMPORARY) && 1202 !(icmp6_nodeinfo & 4)) { 1203 nd6log((LOG_DEBUG, "ni6_input: ignore node info to " 1204 "a temporary address in %s:%d", 1205 __FILE__, __LINE__)); 1206 goto bad; 1207 } 1208 } 1209 1210 /* validate query Subject field. */ 1211 qtype = ntohs(ni6->ni_qtype); 1212 subjlen = m->m_pkthdr.len - off - sizeof(struct icmp6_nodeinfo); 1213 switch (qtype) { 1214 case NI_QTYPE_NOOP: 1215 case NI_QTYPE_SUPTYPES: 1216 /* 07 draft */ 1217 if (ni6->ni_code == ICMP6_NI_SUBJ_FQDN && subjlen == 0) 1218 break; 1219 /* FALLTHROUGH */ 1220 case NI_QTYPE_FQDN: 1221 case NI_QTYPE_NODEADDR: 1222 case NI_QTYPE_IPV4ADDR: 1223 switch (ni6->ni_code) { 1224 case ICMP6_NI_SUBJ_IPV6: 1225 #if ICMP6_NI_SUBJ_IPV6 != 0 1226 case 0: 1227 #endif 1228 /* 1229 * backward compatibility - try to accept 03 draft 1230 * format, where no Subject is present. 1231 */ 1232 if (qtype == NI_QTYPE_FQDN && ni6->ni_code == 0 && 1233 subjlen == 0) { 1234 oldfqdn++; 1235 break; 1236 } 1237 #if ICMP6_NI_SUBJ_IPV6 != 0 1238 if (ni6->ni_code != ICMP6_NI_SUBJ_IPV6) 1239 goto bad; 1240 #endif 1241 1242 if (subjlen != sizeof(struct in6_addr)) 1243 goto bad; 1244 1245 /* 1246 * Validate Subject address. 1247 * 1248 * Not sure what exactly "address belongs to the node" 1249 * means in the spec, is it just unicast, or what? 1250 * 1251 * At this moment we consider Subject address as 1252 * "belong to the node" if the Subject address equals 1253 * to the IPv6 destination address; validation for 1254 * IPv6 destination address should have done enough 1255 * check for us. 1256 * 1257 * We do not do proxy at this moment. 1258 */ 1259 /* m_pulldown instead of copy? */ 1260 m_copydata(m, off + sizeof(struct icmp6_nodeinfo), 1261 subjlen, (caddr_t)&in6_subj); 1262 if (in6_setscope(&in6_subj, m->m_pkthdr.rcvif, NULL)) 1263 goto bad; 1264 1265 subj = (char *)&in6_subj; 1266 if (IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, &in6_subj)) 1267 break; 1268 1269 /* 1270 * XXX if we are to allow other cases, we should really 1271 * be careful about scope here. 1272 * basically, we should disallow queries toward IPv6 1273 * destination X with subject Y, 1274 * if scope(X) > scope(Y). 1275 * if we allow scope(X) > scope(Y), it will result in 1276 * information leakage across scope boundary. 1277 */ 1278 goto bad; 1279 1280 case ICMP6_NI_SUBJ_FQDN: 1281 /* 1282 * Validate Subject name with gethostname(3). 1283 * 1284 * The behavior may need some debate, since: 1285 * - we are not sure if the node has FQDN as 1286 * hostname (returned by gethostname(3)). 1287 * - the code does wildcard match for truncated names. 1288 * however, we are not sure if we want to perform 1289 * wildcard match, if gethostname(3) side has 1290 * truncated hostname. 1291 */ 1292 n = ni6_nametodns(hostname, hostnamelen, 0); 1293 if (!n || n->m_next || n->m_len == 0) 1294 goto bad; 1295 IP6_EXTHDR_GET(subj, char *, m, 1296 off + sizeof(struct icmp6_nodeinfo), subjlen); 1297 if (subj == NULL) 1298 goto bad; 1299 if (!ni6_dnsmatch(subj, subjlen, mtod(n, const char *), 1300 n->m_len)) { 1301 goto bad; 1302 } 1303 m_freem(n); 1304 n = NULL; 1305 break; 1306 1307 case ICMP6_NI_SUBJ_IPV4: /* XXX: to be implemented? */ 1308 default: 1309 goto bad; 1310 } 1311 break; 1312 } 1313 1314 /* refuse based on configuration. XXX ICMP6_NI_REFUSED? */ 1315 switch (qtype) { 1316 case NI_QTYPE_FQDN: 1317 if ((icmp6_nodeinfo & 1) == 0) 1318 goto bad; 1319 break; 1320 case NI_QTYPE_NODEADDR: 1321 case NI_QTYPE_IPV4ADDR: 1322 if ((icmp6_nodeinfo & 2) == 0) 1323 goto bad; 1324 break; 1325 } 1326 1327 /* guess reply length */ 1328 switch (qtype) { 1329 case NI_QTYPE_NOOP: 1330 break; /* no reply data */ 1331 case NI_QTYPE_SUPTYPES: 1332 replylen += sizeof(u_int32_t); 1333 break; 1334 case NI_QTYPE_FQDN: 1335 /* XXX will append an mbuf */ 1336 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1337 break; 1338 case NI_QTYPE_NODEADDR: 1339 addrs = ni6_addrs(ni6, m, &ifp, (struct in6_addr *)subj); 1340 if ((replylen += addrs * (sizeof(struct in6_addr) + 1341 sizeof(u_int32_t))) > MCLBYTES) 1342 replylen = MCLBYTES; /* XXX: will truncate pkt later */ 1343 break; 1344 case NI_QTYPE_IPV4ADDR: 1345 /* unsupported - should respond with unknown Qtype? */ 1346 break; 1347 default: 1348 /* 1349 * XXX: We must return a reply with the ICMP6 code 1350 * `unknown Qtype' in this case. However we regard the case 1351 * as an FQDN query for backward compatibility. 1352 * Older versions set a random value to this field, 1353 * so it rarely varies in the defined qtypes. 1354 * But the mechanism is not reliable... 1355 * maybe we should obsolete older versions. 1356 */ 1357 qtype = NI_QTYPE_FQDN; 1358 /* XXX will append an mbuf */ 1359 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1360 oldfqdn++; 1361 break; 1362 } 1363 1364 /* allocate an mbuf to reply. */ 1365 MGETHDR(n, M_DONTWAIT, m->m_type); 1366 if (n == NULL) { 1367 m_freem(m); 1368 return (NULL); 1369 } 1370 M_MOVE_PKTHDR(n, m); /* just for recvif */ 1371 if (replylen > MHLEN) { 1372 if (replylen > MCLBYTES) { 1373 /* 1374 * XXX: should we try to allocate more? But MCLBYTES 1375 * is probably much larger than IPV6_MMTU... 1376 */ 1377 goto bad; 1378 } 1379 MCLGET(n, M_DONTWAIT); 1380 if ((n->m_flags & M_EXT) == 0) { 1381 goto bad; 1382 } 1383 } 1384 n->m_pkthdr.len = n->m_len = replylen; 1385 1386 /* copy mbuf header and IPv6 + Node Information base headers */ 1387 bcopy(mtod(m, caddr_t), mtod(n, caddr_t), sizeof(struct ip6_hdr)); 1388 nni6 = (struct icmp6_nodeinfo *)(mtod(n, struct ip6_hdr *) + 1); 1389 bcopy((caddr_t)ni6, (caddr_t)nni6, sizeof(struct icmp6_nodeinfo)); 1390 1391 /* qtype dependent procedure */ 1392 switch (qtype) { 1393 case NI_QTYPE_NOOP: 1394 nni6->ni_code = ICMP6_NI_SUCCESS; 1395 nni6->ni_flags = 0; 1396 break; 1397 case NI_QTYPE_SUPTYPES: 1398 { 1399 u_int32_t v; 1400 nni6->ni_code = ICMP6_NI_SUCCESS; 1401 nni6->ni_flags = htons(0x0000); /* raw bitmap */ 1402 /* supports NOOP, SUPTYPES, FQDN, and NODEADDR */ 1403 v = (u_int32_t)htonl(0x0000000f); 1404 bcopy(&v, nni6 + 1, sizeof(u_int32_t)); 1405 break; 1406 } 1407 case NI_QTYPE_FQDN: 1408 nni6->ni_code = ICMP6_NI_SUCCESS; 1409 fqdn = (struct ni_reply_fqdn *)(mtod(n, caddr_t) + 1410 sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo)); 1411 nni6->ni_flags = 0; /* XXX: meaningless TTL */ 1412 fqdn->ni_fqdn_ttl = 0; /* ditto. */ 1413 /* 1414 * XXX do we really have FQDN in variable "hostname"? 1415 */ 1416 n->m_next = ni6_nametodns(hostname, hostnamelen, oldfqdn); 1417 if (n->m_next == NULL) 1418 goto bad; 1419 /* XXX we assume that n->m_next is not a chain */ 1420 if (n->m_next->m_next != NULL) 1421 goto bad; 1422 n->m_pkthdr.len += n->m_next->m_len; 1423 break; 1424 case NI_QTYPE_NODEADDR: 1425 { 1426 int lenlim, copied; 1427 1428 nni6->ni_code = ICMP6_NI_SUCCESS; 1429 n->m_pkthdr.len = n->m_len = 1430 sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo); 1431 lenlim = M_TRAILINGSPACE(n); 1432 copied = ni6_store_addrs(ni6, nni6, ifp, lenlim); 1433 /* XXX: reset mbuf length */ 1434 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) + 1435 sizeof(struct icmp6_nodeinfo) + copied; 1436 break; 1437 } 1438 default: 1439 break; /* XXX impossible! */ 1440 } 1441 1442 nni6->ni_type = ICMP6_NI_REPLY; 1443 m_freem(m); 1444 return (n); 1445 1446 bad: 1447 m_freem(m); 1448 if (n) 1449 m_freem(n); 1450 return (NULL); 1451 } 1452 #undef hostnamelen 1453 1454 /* 1455 * make a mbuf with DNS-encoded string. no compression support. 1456 * 1457 * XXX names with less than 2 dots (like "foo" or "foo.section") will be 1458 * treated as truncated name (two \0 at the end). this is a wild guess. 1459 */ 1460 static struct mbuf * 1461 ni6_nametodns(name, namelen, old) 1462 const char *name; 1463 int namelen; 1464 int old; /* return pascal string if non-zero */ 1465 { 1466 struct mbuf *m; 1467 char *cp, *ep; 1468 const char *p, *q; 1469 int i, len, nterm; 1470 1471 if (old) 1472 len = namelen + 1; 1473 else 1474 len = MCLBYTES; 1475 1476 /* because MAXHOSTNAMELEN is usually 256, we use cluster mbuf */ 1477 MGET(m, M_DONTWAIT, MT_DATA); 1478 if (m && len > MLEN) { 1479 MCLGET(m, M_DONTWAIT); 1480 if ((m->m_flags & M_EXT) == 0) 1481 goto fail; 1482 } 1483 if (!m) 1484 goto fail; 1485 m->m_next = NULL; 1486 1487 if (old) { 1488 m->m_len = len; 1489 *mtod(m, char *) = namelen; 1490 bcopy(name, mtod(m, char *) + 1, namelen); 1491 return m; 1492 } else { 1493 m->m_len = 0; 1494 cp = mtod(m, char *); 1495 ep = mtod(m, char *) + M_TRAILINGSPACE(m); 1496 1497 /* if not certain about my name, return empty buffer */ 1498 if (namelen == 0) 1499 return m; 1500 1501 /* 1502 * guess if it looks like shortened hostname, or FQDN. 1503 * shortened hostname needs two trailing "\0". 1504 */ 1505 i = 0; 1506 for (p = name; p < name + namelen; p++) { 1507 if (*p && *p == '.') 1508 i++; 1509 } 1510 if (i < 2) 1511 nterm = 2; 1512 else 1513 nterm = 1; 1514 1515 p = name; 1516 while (cp < ep && p < name + namelen) { 1517 i = 0; 1518 for (q = p; q < name + namelen && *q && *q != '.'; q++) 1519 i++; 1520 /* result does not fit into mbuf */ 1521 if (cp + i + 1 >= ep) 1522 goto fail; 1523 /* 1524 * DNS label length restriction, RFC1035 page 8. 1525 * "i == 0" case is included here to avoid returning 1526 * 0-length label on "foo..bar". 1527 */ 1528 if (i <= 0 || i >= 64) 1529 goto fail; 1530 *cp++ = i; 1531 bcopy(p, cp, i); 1532 cp += i; 1533 p = q; 1534 if (p < name + namelen && *p == '.') 1535 p++; 1536 } 1537 /* termination */ 1538 if (cp + nterm >= ep) 1539 goto fail; 1540 while (nterm-- > 0) 1541 *cp++ = '\0'; 1542 m->m_len = cp - mtod(m, char *); 1543 return m; 1544 } 1545 1546 panic("should not reach here"); 1547 /* NOTREACHED */ 1548 1549 fail: 1550 if (m) 1551 m_freem(m); 1552 return NULL; 1553 } 1554 1555 /* 1556 * check if two DNS-encoded string matches. takes care of truncated 1557 * form (with \0\0 at the end). no compression support. 1558 * XXX upper/lowercase match (see RFC2065) 1559 */ 1560 static int 1561 ni6_dnsmatch(a, alen, b, blen) 1562 const char *a; 1563 int alen; 1564 const char *b; 1565 int blen; 1566 { 1567 const char *a0, *b0; 1568 int l; 1569 1570 /* simplest case - need validation? */ 1571 if (alen == blen && bcmp(a, b, alen) == 0) 1572 return 1; 1573 1574 a0 = a; 1575 b0 = b; 1576 1577 /* termination is mandatory */ 1578 if (alen < 2 || blen < 2) 1579 return 0; 1580 if (a0[alen - 1] != '\0' || b0[blen - 1] != '\0') 1581 return 0; 1582 alen--; 1583 blen--; 1584 1585 while (a - a0 < alen && b - b0 < blen) { 1586 if (a - a0 + 1 > alen || b - b0 + 1 > blen) 1587 return 0; 1588 1589 if ((signed char)a[0] < 0 || (signed char)b[0] < 0) 1590 return 0; 1591 /* we don't support compression yet */ 1592 if (a[0] >= 64 || b[0] >= 64) 1593 return 0; 1594 1595 /* truncated case */ 1596 if (a[0] == 0 && a - a0 == alen - 1) 1597 return 1; 1598 if (b[0] == 0 && b - b0 == blen - 1) 1599 return 1; 1600 if (a[0] == 0 || b[0] == 0) 1601 return 0; 1602 1603 if (a[0] != b[0]) 1604 return 0; 1605 l = a[0]; 1606 if (a - a0 + 1 + l > alen || b - b0 + 1 + l > blen) 1607 return 0; 1608 if (bcmp(a + 1, b + 1, l) != 0) 1609 return 0; 1610 1611 a += 1 + l; 1612 b += 1 + l; 1613 } 1614 1615 if (a - a0 == alen && b - b0 == blen) 1616 return 1; 1617 else 1618 return 0; 1619 } 1620 1621 /* 1622 * calculate the number of addresses to be returned in the node info reply. 1623 */ 1624 static int 1625 ni6_addrs(ni6, m, ifpp, subj) 1626 struct icmp6_nodeinfo *ni6; 1627 struct mbuf *m; 1628 struct ifnet **ifpp; 1629 struct in6_addr *subj; 1630 { 1631 struct ifnet *ifp; 1632 struct in6_ifaddr *ifa6; 1633 struct ifaddr *ifa; 1634 int addrs = 0, addrsofif, iffound = 0; 1635 int niflags = ni6->ni_flags; 1636 1637 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0) { 1638 switch (ni6->ni_code) { 1639 case ICMP6_NI_SUBJ_IPV6: 1640 if (subj == NULL) /* must be impossible... */ 1641 return (0); 1642 break; 1643 default: 1644 /* 1645 * XXX: we only support IPv6 subject address for 1646 * this Qtype. 1647 */ 1648 return (0); 1649 } 1650 } 1651 1652 IFNET_RLOCK(); 1653 for (ifp = TAILQ_FIRST(&ifnet); ifp; ifp = TAILQ_NEXT(ifp, if_list)) { 1654 addrsofif = 0; 1655 TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list) { 1656 if (ifa->ifa_addr->sa_family != AF_INET6) 1657 continue; 1658 ifa6 = (struct in6_ifaddr *)ifa; 1659 1660 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0 && 1661 IN6_ARE_ADDR_EQUAL(subj, &ifa6->ia_addr.sin6_addr)) 1662 iffound = 1; 1663 1664 /* 1665 * IPv4-mapped addresses can only be returned by a 1666 * Node Information proxy, since they represent 1667 * addresses of IPv4-only nodes, which perforce do 1668 * not implement this protocol. 1669 * [icmp-name-lookups-07, Section 5.4] 1670 * So we don't support NI_NODEADDR_FLAG_COMPAT in 1671 * this function at this moment. 1672 */ 1673 1674 /* What do we have to do about ::1? */ 1675 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1676 case IPV6_ADDR_SCOPE_LINKLOCAL: 1677 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0) 1678 continue; 1679 break; 1680 case IPV6_ADDR_SCOPE_SITELOCAL: 1681 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0) 1682 continue; 1683 break; 1684 case IPV6_ADDR_SCOPE_GLOBAL: 1685 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0) 1686 continue; 1687 break; 1688 default: 1689 continue; 1690 } 1691 1692 /* 1693 * check if anycast is okay. 1694 * XXX: just experimental. not in the spec. 1695 */ 1696 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 && 1697 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0) 1698 continue; /* we need only unicast addresses */ 1699 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 1700 (icmp6_nodeinfo & 4) == 0) { 1701 continue; 1702 } 1703 addrsofif++; /* count the address */ 1704 } 1705 if (iffound) { 1706 *ifpp = ifp; 1707 IFNET_RUNLOCK(); 1708 return (addrsofif); 1709 } 1710 1711 addrs += addrsofif; 1712 } 1713 IFNET_RUNLOCK(); 1714 1715 return (addrs); 1716 } 1717 1718 static int 1719 ni6_store_addrs(ni6, nni6, ifp0, resid) 1720 struct icmp6_nodeinfo *ni6, *nni6; 1721 struct ifnet *ifp0; 1722 int resid; 1723 { 1724 struct ifnet *ifp = ifp0 ? ifp0 : TAILQ_FIRST(&ifnet); 1725 struct in6_ifaddr *ifa6; 1726 struct ifaddr *ifa; 1727 struct ifnet *ifp_dep = NULL; 1728 int copied = 0, allow_deprecated = 0; 1729 u_char *cp = (u_char *)(nni6 + 1); 1730 int niflags = ni6->ni_flags; 1731 u_int32_t ltime; 1732 1733 if (ifp0 == NULL && !(niflags & NI_NODEADDR_FLAG_ALL)) 1734 return (0); /* needless to copy */ 1735 1736 IFNET_RLOCK(); 1737 again: 1738 1739 for (; ifp; ifp = TAILQ_NEXT(ifp, if_list)) { 1740 for (ifa = ifp->if_addrlist.tqh_first; ifa; 1741 ifa = ifa->ifa_list.tqe_next) { 1742 if (ifa->ifa_addr->sa_family != AF_INET6) 1743 continue; 1744 ifa6 = (struct in6_ifaddr *)ifa; 1745 1746 if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) != 0 && 1747 allow_deprecated == 0) { 1748 /* 1749 * prefererred address should be put before 1750 * deprecated addresses. 1751 */ 1752 1753 /* record the interface for later search */ 1754 if (ifp_dep == NULL) 1755 ifp_dep = ifp; 1756 1757 continue; 1758 } else if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) == 0 && 1759 allow_deprecated != 0) 1760 continue; /* we now collect deprecated addrs */ 1761 1762 /* What do we have to do about ::1? */ 1763 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1764 case IPV6_ADDR_SCOPE_LINKLOCAL: 1765 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0) 1766 continue; 1767 break; 1768 case IPV6_ADDR_SCOPE_SITELOCAL: 1769 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0) 1770 continue; 1771 break; 1772 case IPV6_ADDR_SCOPE_GLOBAL: 1773 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0) 1774 continue; 1775 break; 1776 default: 1777 continue; 1778 } 1779 1780 /* 1781 * check if anycast is okay. 1782 * XXX: just experimental. not in the spec. 1783 */ 1784 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 && 1785 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0) 1786 continue; 1787 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 1788 (icmp6_nodeinfo & 4) == 0) { 1789 continue; 1790 } 1791 1792 /* now we can copy the address */ 1793 if (resid < sizeof(struct in6_addr) + 1794 sizeof(u_int32_t)) { 1795 /* 1796 * We give up much more copy. 1797 * Set the truncate flag and return. 1798 */ 1799 nni6->ni_flags |= NI_NODEADDR_FLAG_TRUNCATE; 1800 IFNET_RUNLOCK(); 1801 return (copied); 1802 } 1803 1804 /* 1805 * Set the TTL of the address. 1806 * The TTL value should be one of the following 1807 * according to the specification: 1808 * 1809 * 1. The remaining lifetime of a DHCP lease on the 1810 * address, or 1811 * 2. The remaining Valid Lifetime of a prefix from 1812 * which the address was derived through Stateless 1813 * Autoconfiguration. 1814 * 1815 * Note that we currently do not support stateful 1816 * address configuration by DHCPv6, so the former 1817 * case can't happen. 1818 */ 1819 if (ifa6->ia6_lifetime.ia6t_expire == 0) 1820 ltime = ND6_INFINITE_LIFETIME; 1821 else { 1822 if (ifa6->ia6_lifetime.ia6t_expire > 1823 time_second) 1824 ltime = htonl(ifa6->ia6_lifetime.ia6t_expire - time_second); 1825 else 1826 ltime = 0; 1827 } 1828 1829 bcopy(<ime, cp, sizeof(u_int32_t)); 1830 cp += sizeof(u_int32_t); 1831 1832 /* copy the address itself */ 1833 bcopy(&ifa6->ia_addr.sin6_addr, cp, 1834 sizeof(struct in6_addr)); 1835 in6_clearscope((struct in6_addr *)cp); /* XXX */ 1836 cp += sizeof(struct in6_addr); 1837 1838 resid -= (sizeof(struct in6_addr) + sizeof(u_int32_t)); 1839 copied += (sizeof(struct in6_addr) + sizeof(u_int32_t)); 1840 } 1841 if (ifp0) /* we need search only on the specified IF */ 1842 break; 1843 } 1844 1845 if (allow_deprecated == 0 && ifp_dep != NULL) { 1846 ifp = ifp_dep; 1847 allow_deprecated = 1; 1848 1849 goto again; 1850 } 1851 1852 IFNET_RUNLOCK(); 1853 1854 return (copied); 1855 } 1856 1857 /* 1858 * XXX almost dup'ed code with rip6_input. 1859 */ 1860 static int 1861 icmp6_rip6_input(mp, off) 1862 struct mbuf **mp; 1863 int off; 1864 { 1865 struct mbuf *m = *mp; 1866 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1867 struct in6pcb *in6p; 1868 struct in6pcb *last = NULL; 1869 struct sockaddr_in6 fromsa; 1870 struct icmp6_hdr *icmp6; 1871 struct mbuf *opts = NULL; 1872 1873 #ifndef PULLDOWN_TEST 1874 /* this is assumed to be safe. */ 1875 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off); 1876 #else 1877 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 1878 if (icmp6 == NULL) { 1879 /* m is already reclaimed */ 1880 return (IPPROTO_DONE); 1881 } 1882 #endif 1883 1884 /* 1885 * XXX: the address may have embedded scope zone ID, which should be 1886 * hidden from applications. 1887 */ 1888 bzero(&fromsa, sizeof(fromsa)); 1889 fromsa.sin6_family = AF_INET6; 1890 fromsa.sin6_len = sizeof(struct sockaddr_in6); 1891 fromsa.sin6_addr = ip6->ip6_src; 1892 if (sa6_recoverscope(&fromsa)) { 1893 m_freem(m); 1894 return (IPPROTO_DONE); 1895 } 1896 1897 INP_INFO_RLOCK(&ripcbinfo); 1898 LIST_FOREACH(in6p, &ripcb, inp_list) { 1899 INP_LOCK(in6p); 1900 if ((in6p->inp_vflag & INP_IPV6) == 0) { 1901 docontinue: 1902 INP_UNLOCK(in6p); 1903 continue; 1904 } 1905 if (in6p->in6p_ip6_nxt != IPPROTO_ICMPV6) 1906 goto docontinue; 1907 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr) && 1908 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr, &ip6->ip6_dst)) 1909 goto docontinue; 1910 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr) && 1911 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr, &ip6->ip6_src)) 1912 goto docontinue; 1913 if (in6p->in6p_icmp6filt 1914 && ICMP6_FILTER_WILLBLOCK(icmp6->icmp6_type, 1915 in6p->in6p_icmp6filt)) 1916 goto docontinue; 1917 if (last) { 1918 struct mbuf *n = NULL; 1919 1920 /* 1921 * Recent network drivers tend to allocate a single 1922 * mbuf cluster, rather than to make a couple of 1923 * mbufs without clusters. Also, since the IPv6 code 1924 * path tries to avoid m_pullup(), it is highly 1925 * probable that we still have an mbuf cluster here 1926 * even though the necessary length can be stored in an 1927 * mbuf's internal buffer. 1928 * Meanwhile, the default size of the receive socket 1929 * buffer for raw sockets is not so large. This means 1930 * the possibility of packet loss is relatively higher 1931 * than before. To avoid this scenario, we copy the 1932 * received data to a separate mbuf that does not use 1933 * a cluster, if possible. 1934 * XXX: it is better to copy the data after stripping 1935 * intermediate headers. 1936 */ 1937 if ((m->m_flags & M_EXT) && m->m_next == NULL && 1938 m->m_len <= MHLEN) { 1939 MGET(n, M_DONTWAIT, m->m_type); 1940 if (n != NULL) { 1941 if (m_dup_pkthdr(n, m, M_NOWAIT)) { 1942 bcopy(m->m_data, n->m_data, 1943 m->m_len); 1944 n->m_len = m->m_len; 1945 } else { 1946 m_free(n); 1947 n = NULL; 1948 } 1949 } 1950 } 1951 if (n != NULL || 1952 (n = m_copy(m, 0, (int)M_COPYALL)) != NULL) { 1953 if (last->in6p_flags & IN6P_CONTROLOPTS) 1954 ip6_savecontrol(last, n, &opts); 1955 /* strip intermediate headers */ 1956 m_adj(n, off); 1957 if (sbappendaddr(&last->in6p_socket->so_rcv, 1958 (struct sockaddr *)&fromsa, n, opts) 1959 == 0) { 1960 /* should notify about lost packet */ 1961 m_freem(n); 1962 if (opts) { 1963 m_freem(opts); 1964 } 1965 } else 1966 sorwakeup(last->in6p_socket); 1967 opts = NULL; 1968 } 1969 INP_UNLOCK(last); 1970 } 1971 last = in6p; 1972 } 1973 if (last) { 1974 if (last->in6p_flags & IN6P_CONTROLOPTS) 1975 ip6_savecontrol(last, m, &opts); 1976 /* strip intermediate headers */ 1977 m_adj(m, off); 1978 1979 /* avoid using mbuf clusters if possible (see above) */ 1980 if ((m->m_flags & M_EXT) && m->m_next == NULL && 1981 m->m_len <= MHLEN) { 1982 struct mbuf *n; 1983 1984 MGET(n, M_DONTWAIT, m->m_type); 1985 if (n != NULL) { 1986 if (m_dup_pkthdr(n, m, M_NOWAIT)) { 1987 bcopy(m->m_data, n->m_data, m->m_len); 1988 n->m_len = m->m_len; 1989 1990 m_freem(m); 1991 m = n; 1992 } else { 1993 m_freem(n); 1994 n = NULL; 1995 } 1996 } 1997 } 1998 if (sbappendaddr(&last->in6p_socket->so_rcv, 1999 (struct sockaddr *)&fromsa, m, opts) == 0) { 2000 m_freem(m); 2001 if (opts) 2002 m_freem(opts); 2003 } else 2004 sorwakeup(last->in6p_socket); 2005 INP_UNLOCK(last); 2006 } else { 2007 m_freem(m); 2008 ip6stat.ip6s_delivered--; 2009 } 2010 INP_INFO_RUNLOCK(&ripcbinfo); 2011 return IPPROTO_DONE; 2012 } 2013 2014 /* 2015 * Reflect the ip6 packet back to the source. 2016 * OFF points to the icmp6 header, counted from the top of the mbuf. 2017 */ 2018 void 2019 icmp6_reflect(m, off) 2020 struct mbuf *m; 2021 size_t off; 2022 { 2023 struct ip6_hdr *ip6; 2024 struct icmp6_hdr *icmp6; 2025 struct in6_ifaddr *ia; 2026 int plen; 2027 int type, code; 2028 struct ifnet *outif = NULL; 2029 struct in6_addr origdst, *src = NULL; 2030 2031 /* too short to reflect */ 2032 if (off < sizeof(struct ip6_hdr)) { 2033 nd6log((LOG_DEBUG, 2034 "sanity fail: off=%lx, sizeof(ip6)=%lx in %s:%d\n", 2035 (u_long)off, (u_long)sizeof(struct ip6_hdr), 2036 __FILE__, __LINE__)); 2037 goto bad; 2038 } 2039 2040 /* 2041 * If there are extra headers between IPv6 and ICMPv6, strip 2042 * off that header first. 2043 */ 2044 #ifdef DIAGNOSTIC 2045 if (sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) > MHLEN) 2046 panic("assumption failed in icmp6_reflect"); 2047 #endif 2048 if (off > sizeof(struct ip6_hdr)) { 2049 size_t l; 2050 struct ip6_hdr nip6; 2051 2052 l = off - sizeof(struct ip6_hdr); 2053 m_copydata(m, 0, sizeof(nip6), (caddr_t)&nip6); 2054 m_adj(m, l); 2055 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 2056 if (m->m_len < l) { 2057 if ((m = m_pullup(m, l)) == NULL) 2058 return; 2059 } 2060 bcopy((caddr_t)&nip6, mtod(m, caddr_t), sizeof(nip6)); 2061 } else /* off == sizeof(struct ip6_hdr) */ { 2062 size_t l; 2063 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 2064 if (m->m_len < l) { 2065 if ((m = m_pullup(m, l)) == NULL) 2066 return; 2067 } 2068 } 2069 plen = m->m_pkthdr.len - sizeof(struct ip6_hdr); 2070 ip6 = mtod(m, struct ip6_hdr *); 2071 ip6->ip6_nxt = IPPROTO_ICMPV6; 2072 icmp6 = (struct icmp6_hdr *)(ip6 + 1); 2073 type = icmp6->icmp6_type; /* keep type for statistics */ 2074 code = icmp6->icmp6_code; /* ditto. */ 2075 2076 origdst = ip6->ip6_dst; 2077 /* 2078 * ip6_input() drops a packet if its src is multicast. 2079 * So, the src is never multicast. 2080 */ 2081 ip6->ip6_dst = ip6->ip6_src; 2082 2083 /* 2084 * If the incoming packet was addressed directly to us (i.e. unicast), 2085 * use dst as the src for the reply. 2086 * The IN6_IFF_NOTREADY case should be VERY rare, but is possible 2087 * (for example) when we encounter an error while forwarding procedure 2088 * destined to a duplicated address of ours. 2089 * Note that ip6_getdstifaddr() may fail if we are in an error handling 2090 * procedure of an outgoing packet of our own, in which case we need 2091 * to search in the ifaddr list. 2092 */ 2093 if (!IN6_IS_ADDR_MULTICAST(&origdst)) { 2094 if ((ia = ip6_getdstifaddr(m))) { 2095 if (!(ia->ia6_flags & 2096 (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY))) 2097 src = &ia->ia_addr.sin6_addr; 2098 } else { 2099 struct sockaddr_in6 d; 2100 2101 bzero(&d, sizeof(d)); 2102 d.sin6_family = AF_INET6; 2103 d.sin6_len = sizeof(d); 2104 d.sin6_addr = origdst; 2105 ia = (struct in6_ifaddr *) 2106 ifa_ifwithaddr((struct sockaddr *)&d); 2107 if (ia && 2108 !(ia->ia6_flags & 2109 (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY))) { 2110 src = &ia->ia_addr.sin6_addr; 2111 } 2112 } 2113 } 2114 2115 if (src == NULL) { 2116 int e; 2117 struct sockaddr_in6 sin6; 2118 struct route_in6 ro; 2119 2120 /* 2121 * This case matches to multicasts, our anycast, or unicasts 2122 * that we do not own. Select a source address based on the 2123 * source address of the erroneous packet. 2124 */ 2125 bzero(&sin6, sizeof(sin6)); 2126 sin6.sin6_family = AF_INET6; 2127 sin6.sin6_len = sizeof(sin6); 2128 sin6.sin6_addr = ip6->ip6_dst; /* zone ID should be embedded */ 2129 2130 bzero(&ro, sizeof(ro)); 2131 src = in6_selectsrc(&sin6, NULL, NULL, &ro, NULL, &outif, &e); 2132 if (ro.ro_rt) 2133 RTFREE(ro.ro_rt); /* XXX: we could use this */ 2134 if (src == NULL) { 2135 nd6log((LOG_DEBUG, 2136 "icmp6_reflect: source can't be determined: " 2137 "dst=%s, error=%d\n", 2138 ip6_sprintf(&sin6.sin6_addr), e)); 2139 goto bad; 2140 } 2141 } 2142 2143 ip6->ip6_src = *src; 2144 ip6->ip6_flow = 0; 2145 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2146 ip6->ip6_vfc |= IPV6_VERSION; 2147 ip6->ip6_nxt = IPPROTO_ICMPV6; 2148 if (outif) 2149 ip6->ip6_hlim = ND_IFINFO(outif)->chlim; 2150 else if (m->m_pkthdr.rcvif) { 2151 /* XXX: This may not be the outgoing interface */ 2152 ip6->ip6_hlim = ND_IFINFO(m->m_pkthdr.rcvif)->chlim; 2153 } else 2154 ip6->ip6_hlim = ip6_defhlim; 2155 2156 icmp6->icmp6_cksum = 0; 2157 icmp6->icmp6_cksum = in6_cksum(m, IPPROTO_ICMPV6, 2158 sizeof(struct ip6_hdr), plen); 2159 2160 /* 2161 * XXX option handling 2162 */ 2163 2164 m->m_flags &= ~(M_BCAST|M_MCAST); 2165 2166 ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL); 2167 if (outif) 2168 icmp6_ifoutstat_inc(outif, type, code); 2169 2170 return; 2171 2172 bad: 2173 m_freem(m); 2174 return; 2175 } 2176 2177 void 2178 icmp6_fasttimo() 2179 { 2180 2181 return; 2182 } 2183 2184 static const char * 2185 icmp6_redirect_diag(src6, dst6, tgt6) 2186 struct in6_addr *src6; 2187 struct in6_addr *dst6; 2188 struct in6_addr *tgt6; 2189 { 2190 static char buf[1024]; 2191 snprintf(buf, sizeof(buf), "(src=%s dst=%s tgt=%s)", 2192 ip6_sprintf(src6), ip6_sprintf(dst6), ip6_sprintf(tgt6)); 2193 return buf; 2194 } 2195 2196 void 2197 icmp6_redirect_input(m, off) 2198 struct mbuf *m; 2199 int off; 2200 { 2201 struct ifnet *ifp = m->m_pkthdr.rcvif; 2202 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 2203 struct nd_redirect *nd_rd; 2204 int icmp6len = ntohs(ip6->ip6_plen); 2205 char *lladdr = NULL; 2206 int lladdrlen = 0; 2207 u_char *redirhdr = NULL; 2208 int redirhdrlen = 0; 2209 struct rtentry *rt = NULL; 2210 int is_router; 2211 int is_onlink; 2212 struct in6_addr src6 = ip6->ip6_src; 2213 struct in6_addr redtgt6; 2214 struct in6_addr reddst6; 2215 union nd_opts ndopts; 2216 2217 if (!m || !ifp) 2218 return; 2219 2220 /* XXX if we are router, we don't update route by icmp6 redirect */ 2221 if (ip6_forwarding) 2222 goto freeit; 2223 if (!icmp6_rediraccept) 2224 goto freeit; 2225 2226 #ifndef PULLDOWN_TEST 2227 IP6_EXTHDR_CHECK(m, off, icmp6len,); 2228 nd_rd = (struct nd_redirect *)((caddr_t)ip6 + off); 2229 #else 2230 IP6_EXTHDR_GET(nd_rd, struct nd_redirect *, m, off, icmp6len); 2231 if (nd_rd == NULL) { 2232 icmp6stat.icp6s_tooshort++; 2233 return; 2234 } 2235 #endif 2236 redtgt6 = nd_rd->nd_rd_target; 2237 reddst6 = nd_rd->nd_rd_dst; 2238 2239 if (in6_setscope(&redtgt6, m->m_pkthdr.rcvif, NULL) || 2240 in6_setscope(&reddst6, m->m_pkthdr.rcvif, NULL)) { 2241 goto freeit; 2242 } 2243 2244 /* validation */ 2245 if (!IN6_IS_ADDR_LINKLOCAL(&src6)) { 2246 nd6log((LOG_ERR, 2247 "ICMP6 redirect sent from %s rejected; " 2248 "must be from linklocal\n", 2249 ip6_sprintf(&src6))); 2250 goto bad; 2251 } 2252 if (ip6->ip6_hlim != 255) { 2253 nd6log((LOG_ERR, 2254 "ICMP6 redirect sent from %s rejected; " 2255 "hlim=%d (must be 255)\n", 2256 ip6_sprintf(&src6), ip6->ip6_hlim)); 2257 goto bad; 2258 } 2259 { 2260 /* ip6->ip6_src must be equal to gw for icmp6->icmp6_reddst */ 2261 struct sockaddr_in6 sin6; 2262 struct in6_addr *gw6; 2263 2264 bzero(&sin6, sizeof(sin6)); 2265 sin6.sin6_family = AF_INET6; 2266 sin6.sin6_len = sizeof(struct sockaddr_in6); 2267 bcopy(&reddst6, &sin6.sin6_addr, sizeof(reddst6)); 2268 rt = rtalloc1((struct sockaddr *)&sin6, 0, 0UL); 2269 if (rt) { 2270 if (rt->rt_gateway == NULL || 2271 rt->rt_gateway->sa_family != AF_INET6) { 2272 nd6log((LOG_ERR, 2273 "ICMP6 redirect rejected; no route " 2274 "with inet6 gateway found for redirect dst: %s\n", 2275 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2276 RTFREE_LOCKED(rt); 2277 goto bad; 2278 } 2279 2280 gw6 = &(((struct sockaddr_in6 *)rt->rt_gateway)->sin6_addr); 2281 if (bcmp(&src6, gw6, sizeof(struct in6_addr)) != 0) { 2282 nd6log((LOG_ERR, 2283 "ICMP6 redirect rejected; " 2284 "not equal to gw-for-src=%s (must be same): " 2285 "%s\n", 2286 ip6_sprintf(gw6), 2287 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2288 RTFREE_LOCKED(rt); 2289 goto bad; 2290 } 2291 } else { 2292 nd6log((LOG_ERR, 2293 "ICMP6 redirect rejected; " 2294 "no route found for redirect dst: %s\n", 2295 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2296 goto bad; 2297 } 2298 RTFREE_LOCKED(rt); 2299 rt = NULL; 2300 } 2301 if (IN6_IS_ADDR_MULTICAST(&reddst6)) { 2302 nd6log((LOG_ERR, 2303 "ICMP6 redirect rejected; " 2304 "redirect dst must be unicast: %s\n", 2305 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2306 goto bad; 2307 } 2308 2309 is_router = is_onlink = 0; 2310 if (IN6_IS_ADDR_LINKLOCAL(&redtgt6)) 2311 is_router = 1; /* router case */ 2312 if (bcmp(&redtgt6, &reddst6, sizeof(redtgt6)) == 0) 2313 is_onlink = 1; /* on-link destination case */ 2314 if (!is_router && !is_onlink) { 2315 nd6log((LOG_ERR, 2316 "ICMP6 redirect rejected; " 2317 "neither router case nor onlink case: %s\n", 2318 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2319 goto bad; 2320 } 2321 /* validation passed */ 2322 2323 icmp6len -= sizeof(*nd_rd); 2324 nd6_option_init(nd_rd + 1, icmp6len, &ndopts); 2325 if (nd6_options(&ndopts) < 0) { 2326 nd6log((LOG_INFO, "icmp6_redirect_input: " 2327 "invalid ND option, rejected: %s\n", 2328 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2329 /* nd6_options have incremented stats */ 2330 goto freeit; 2331 } 2332 2333 if (ndopts.nd_opts_tgt_lladdr) { 2334 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 2335 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 2336 } 2337 2338 if (ndopts.nd_opts_rh) { 2339 redirhdrlen = ndopts.nd_opts_rh->nd_opt_rh_len; 2340 redirhdr = (u_char *)(ndopts.nd_opts_rh + 1); /* xxx */ 2341 } 2342 2343 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 2344 nd6log((LOG_INFO, 2345 "icmp6_redirect_input: lladdrlen mismatch for %s " 2346 "(if %d, icmp6 packet %d): %s\n", 2347 ip6_sprintf(&redtgt6), ifp->if_addrlen, lladdrlen - 2, 2348 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2349 goto bad; 2350 } 2351 2352 /* RFC 2461 8.3 */ 2353 nd6_cache_lladdr(ifp, &redtgt6, lladdr, lladdrlen, ND_REDIRECT, 2354 is_onlink ? ND_REDIRECT_ONLINK : ND_REDIRECT_ROUTER); 2355 2356 if (!is_onlink) { /* better router case. perform rtredirect. */ 2357 /* perform rtredirect */ 2358 struct sockaddr_in6 sdst; 2359 struct sockaddr_in6 sgw; 2360 struct sockaddr_in6 ssrc; 2361 2362 bzero(&sdst, sizeof(sdst)); 2363 bzero(&sgw, sizeof(sgw)); 2364 bzero(&ssrc, sizeof(ssrc)); 2365 sdst.sin6_family = sgw.sin6_family = ssrc.sin6_family = AF_INET6; 2366 sdst.sin6_len = sgw.sin6_len = ssrc.sin6_len = 2367 sizeof(struct sockaddr_in6); 2368 bcopy(&redtgt6, &sgw.sin6_addr, sizeof(struct in6_addr)); 2369 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2370 bcopy(&src6, &ssrc.sin6_addr, sizeof(struct in6_addr)); 2371 rtredirect((struct sockaddr *)&sdst, (struct sockaddr *)&sgw, 2372 (struct sockaddr *)NULL, RTF_GATEWAY | RTF_HOST, 2373 (struct sockaddr *)&ssrc); 2374 } 2375 /* finally update cached route in each socket via pfctlinput */ 2376 { 2377 struct sockaddr_in6 sdst; 2378 2379 bzero(&sdst, sizeof(sdst)); 2380 sdst.sin6_family = AF_INET6; 2381 sdst.sin6_len = sizeof(struct sockaddr_in6); 2382 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2383 pfctlinput(PRC_REDIRECT_HOST, (struct sockaddr *)&sdst); 2384 #if defined(IPSEC) || defined(FAST_IPSEC) 2385 key_sa_routechange((struct sockaddr *)&sdst); 2386 #endif 2387 } 2388 2389 freeit: 2390 m_freem(m); 2391 return; 2392 2393 bad: 2394 icmp6stat.icp6s_badredirect++; 2395 m_freem(m); 2396 } 2397 2398 void 2399 icmp6_redirect_output(m0, rt) 2400 struct mbuf *m0; 2401 struct rtentry *rt; 2402 { 2403 struct ifnet *ifp; /* my outgoing interface */ 2404 struct in6_addr *ifp_ll6; 2405 struct in6_addr *router_ll6; 2406 struct ip6_hdr *sip6; /* m0 as struct ip6_hdr */ 2407 struct mbuf *m = NULL; /* newly allocated one */ 2408 struct ip6_hdr *ip6; /* m as struct ip6_hdr */ 2409 struct nd_redirect *nd_rd; 2410 size_t maxlen; 2411 u_char *p; 2412 struct ifnet *outif = NULL; 2413 struct sockaddr_in6 src_sa; 2414 2415 icmp6_errcount(&icmp6stat.icp6s_outerrhist, ND_REDIRECT, 0); 2416 2417 /* if we are not router, we don't send icmp6 redirect */ 2418 if (!ip6_forwarding) 2419 goto fail; 2420 2421 /* sanity check */ 2422 if (!m0 || !rt || !(rt->rt_flags & RTF_UP) || !(ifp = rt->rt_ifp)) 2423 goto fail; 2424 2425 /* 2426 * Address check: 2427 * the source address must identify a neighbor, and 2428 * the destination address must not be a multicast address 2429 * [RFC 2461, sec 8.2] 2430 */ 2431 sip6 = mtod(m0, struct ip6_hdr *); 2432 bzero(&src_sa, sizeof(src_sa)); 2433 src_sa.sin6_family = AF_INET6; 2434 src_sa.sin6_len = sizeof(src_sa); 2435 src_sa.sin6_addr = sip6->ip6_src; 2436 if (nd6_is_addr_neighbor(&src_sa, ifp) == 0) 2437 goto fail; 2438 if (IN6_IS_ADDR_MULTICAST(&sip6->ip6_dst)) 2439 goto fail; /* what should we do here? */ 2440 2441 /* rate limit */ 2442 if (icmp6_ratelimit(&sip6->ip6_src, ND_REDIRECT, 0)) 2443 goto fail; 2444 2445 /* 2446 * Since we are going to append up to 1280 bytes (= IPV6_MMTU), 2447 * we almost always ask for an mbuf cluster for simplicity. 2448 * (MHLEN < IPV6_MMTU is almost always true) 2449 */ 2450 #if IPV6_MMTU >= MCLBYTES 2451 # error assumption failed about IPV6_MMTU and MCLBYTES 2452 #endif 2453 MGETHDR(m, M_DONTWAIT, MT_HEADER); 2454 if (m && IPV6_MMTU >= MHLEN) 2455 MCLGET(m, M_DONTWAIT); 2456 if (!m) 2457 goto fail; 2458 m->m_pkthdr.rcvif = NULL; 2459 m->m_len = 0; 2460 maxlen = M_TRAILINGSPACE(m); 2461 maxlen = min(IPV6_MMTU, maxlen); 2462 /* just for safety */ 2463 if (maxlen < sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) + 2464 ((sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7)) { 2465 goto fail; 2466 } 2467 2468 { 2469 /* get ip6 linklocal address for ifp(my outgoing interface). */ 2470 struct in6_ifaddr *ia; 2471 if ((ia = in6ifa_ifpforlinklocal(ifp, 2472 IN6_IFF_NOTREADY| 2473 IN6_IFF_ANYCAST)) == NULL) 2474 goto fail; 2475 ifp_ll6 = &ia->ia_addr.sin6_addr; 2476 } 2477 2478 /* get ip6 linklocal address for the router. */ 2479 if (rt->rt_gateway && (rt->rt_flags & RTF_GATEWAY)) { 2480 struct sockaddr_in6 *sin6; 2481 sin6 = (struct sockaddr_in6 *)rt->rt_gateway; 2482 router_ll6 = &sin6->sin6_addr; 2483 if (!IN6_IS_ADDR_LINKLOCAL(router_ll6)) 2484 router_ll6 = (struct in6_addr *)NULL; 2485 } else 2486 router_ll6 = (struct in6_addr *)NULL; 2487 2488 /* ip6 */ 2489 ip6 = mtod(m, struct ip6_hdr *); 2490 ip6->ip6_flow = 0; 2491 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2492 ip6->ip6_vfc |= IPV6_VERSION; 2493 /* ip6->ip6_plen will be set later */ 2494 ip6->ip6_nxt = IPPROTO_ICMPV6; 2495 ip6->ip6_hlim = 255; 2496 /* ip6->ip6_src must be linklocal addr for my outgoing if. */ 2497 bcopy(ifp_ll6, &ip6->ip6_src, sizeof(struct in6_addr)); 2498 bcopy(&sip6->ip6_src, &ip6->ip6_dst, sizeof(struct in6_addr)); 2499 2500 /* ND Redirect */ 2501 nd_rd = (struct nd_redirect *)(ip6 + 1); 2502 nd_rd->nd_rd_type = ND_REDIRECT; 2503 nd_rd->nd_rd_code = 0; 2504 nd_rd->nd_rd_reserved = 0; 2505 if (rt->rt_flags & RTF_GATEWAY) { 2506 /* 2507 * nd_rd->nd_rd_target must be a link-local address in 2508 * better router cases. 2509 */ 2510 if (!router_ll6) 2511 goto fail; 2512 bcopy(router_ll6, &nd_rd->nd_rd_target, 2513 sizeof(nd_rd->nd_rd_target)); 2514 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2515 sizeof(nd_rd->nd_rd_dst)); 2516 } else { 2517 /* make sure redtgt == reddst */ 2518 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_target, 2519 sizeof(nd_rd->nd_rd_target)); 2520 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2521 sizeof(nd_rd->nd_rd_dst)); 2522 } 2523 2524 p = (u_char *)(nd_rd + 1); 2525 2526 if (!router_ll6) 2527 goto nolladdropt; 2528 2529 { 2530 /* target lladdr option */ 2531 struct rtentry *rt_router = NULL; 2532 int len; 2533 struct sockaddr_dl *sdl; 2534 struct nd_opt_hdr *nd_opt; 2535 char *lladdr; 2536 2537 rt_router = nd6_lookup(router_ll6, 0, ifp); 2538 if (!rt_router) 2539 goto nolladdropt; 2540 len = sizeof(*nd_opt) + ifp->if_addrlen; 2541 len = (len + 7) & ~7; /* round by 8 */ 2542 /* safety check */ 2543 if (len + (p - (u_char *)ip6) > maxlen) 2544 goto nolladdropt; 2545 if (!(rt_router->rt_flags & RTF_GATEWAY) && 2546 (rt_router->rt_flags & RTF_LLINFO) && 2547 (rt_router->rt_gateway->sa_family == AF_LINK) && 2548 (sdl = (struct sockaddr_dl *)rt_router->rt_gateway) && 2549 sdl->sdl_alen) { 2550 nd_opt = (struct nd_opt_hdr *)p; 2551 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 2552 nd_opt->nd_opt_len = len >> 3; 2553 lladdr = (char *)(nd_opt + 1); 2554 bcopy(LLADDR(sdl), lladdr, ifp->if_addrlen); 2555 p += len; 2556 } 2557 } 2558 nolladdropt:; 2559 2560 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2561 2562 /* just to be safe */ 2563 #ifdef M_DECRYPTED /*not openbsd*/ 2564 if (m0->m_flags & M_DECRYPTED) 2565 goto noredhdropt; 2566 #endif 2567 if (p - (u_char *)ip6 > maxlen) 2568 goto noredhdropt; 2569 2570 { 2571 /* redirected header option */ 2572 int len; 2573 struct nd_opt_rd_hdr *nd_opt_rh; 2574 2575 /* 2576 * compute the maximum size for icmp6 redirect header option. 2577 * XXX room for auth header? 2578 */ 2579 len = maxlen - (p - (u_char *)ip6); 2580 len &= ~7; 2581 2582 /* This is just for simplicity. */ 2583 if (m0->m_pkthdr.len != m0->m_len) { 2584 if (m0->m_next) { 2585 m_freem(m0->m_next); 2586 m0->m_next = NULL; 2587 } 2588 m0->m_pkthdr.len = m0->m_len; 2589 } 2590 2591 /* 2592 * Redirected header option spec (RFC2461 4.6.3) talks nothing 2593 * about padding/truncate rule for the original IP packet. 2594 * From the discussion on IPv6imp in Feb 1999, 2595 * the consensus was: 2596 * - "attach as much as possible" is the goal 2597 * - pad if not aligned (original size can be guessed by 2598 * original ip6 header) 2599 * Following code adds the padding if it is simple enough, 2600 * and truncates if not. 2601 */ 2602 if (m0->m_next || m0->m_pkthdr.len != m0->m_len) 2603 panic("assumption failed in %s:%d", __FILE__, 2604 __LINE__); 2605 2606 if (len - sizeof(*nd_opt_rh) < m0->m_pkthdr.len) { 2607 /* not enough room, truncate */ 2608 m0->m_pkthdr.len = m0->m_len = len - 2609 sizeof(*nd_opt_rh); 2610 } else { 2611 /* enough room, pad or truncate */ 2612 size_t extra; 2613 2614 extra = m0->m_pkthdr.len % 8; 2615 if (extra) { 2616 /* pad if easy enough, truncate if not */ 2617 if (8 - extra <= M_TRAILINGSPACE(m0)) { 2618 /* pad */ 2619 m0->m_len += (8 - extra); 2620 m0->m_pkthdr.len += (8 - extra); 2621 } else { 2622 /* truncate */ 2623 m0->m_pkthdr.len -= extra; 2624 m0->m_len -= extra; 2625 } 2626 } 2627 len = m0->m_pkthdr.len + sizeof(*nd_opt_rh); 2628 m0->m_pkthdr.len = m0->m_len = len - 2629 sizeof(*nd_opt_rh); 2630 } 2631 2632 nd_opt_rh = (struct nd_opt_rd_hdr *)p; 2633 bzero(nd_opt_rh, sizeof(*nd_opt_rh)); 2634 nd_opt_rh->nd_opt_rh_type = ND_OPT_REDIRECTED_HEADER; 2635 nd_opt_rh->nd_opt_rh_len = len >> 3; 2636 p += sizeof(*nd_opt_rh); 2637 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2638 2639 /* connect m0 to m */ 2640 m_tag_delete_chain(m0, NULL); 2641 m0->m_flags &= ~M_PKTHDR; 2642 m->m_next = m0; 2643 m->m_pkthdr.len = m->m_len + m0->m_len; 2644 m0 = NULL; 2645 } 2646 noredhdropt:; 2647 if (m0) { 2648 m_freem(m0); 2649 m0 = NULL; 2650 } 2651 2652 /* XXX: clear embedded link IDs in the inner header */ 2653 in6_clearscope(&sip6->ip6_src); 2654 in6_clearscope(&sip6->ip6_dst); 2655 in6_clearscope(&nd_rd->nd_rd_target); 2656 in6_clearscope(&nd_rd->nd_rd_dst); 2657 2658 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr)); 2659 2660 nd_rd->nd_rd_cksum = 0; 2661 nd_rd->nd_rd_cksum = in6_cksum(m, IPPROTO_ICMPV6, 2662 sizeof(*ip6), ntohs(ip6->ip6_plen)); 2663 2664 /* send the packet to outside... */ 2665 ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL); 2666 if (outif) { 2667 icmp6_ifstat_inc(outif, ifs6_out_msg); 2668 icmp6_ifstat_inc(outif, ifs6_out_redirect); 2669 } 2670 icmp6stat.icp6s_outhist[ND_REDIRECT]++; 2671 2672 return; 2673 2674 fail: 2675 if (m) 2676 m_freem(m); 2677 if (m0) 2678 m_freem(m0); 2679 } 2680 2681 /* 2682 * ICMPv6 socket option processing. 2683 */ 2684 int 2685 icmp6_ctloutput(so, sopt) 2686 struct socket *so; 2687 struct sockopt *sopt; 2688 { 2689 int error = 0; 2690 int optlen; 2691 struct inpcb *inp = sotoinpcb(so); 2692 int level, op, optname; 2693 2694 if (sopt) { 2695 level = sopt->sopt_level; 2696 op = sopt->sopt_dir; 2697 optname = sopt->sopt_name; 2698 optlen = sopt->sopt_valsize; 2699 } else 2700 level = op = optname = optlen = 0; 2701 2702 if (level != IPPROTO_ICMPV6) { 2703 return EINVAL; 2704 } 2705 2706 switch (op) { 2707 case PRCO_SETOPT: 2708 switch (optname) { 2709 case ICMP6_FILTER: 2710 { 2711 struct icmp6_filter *p; 2712 2713 if (optlen != sizeof(*p)) { 2714 error = EMSGSIZE; 2715 break; 2716 } 2717 if (inp->in6p_icmp6filt == NULL) { 2718 error = EINVAL; 2719 break; 2720 } 2721 error = sooptcopyin(sopt, inp->in6p_icmp6filt, optlen, 2722 optlen); 2723 break; 2724 } 2725 2726 default: 2727 error = ENOPROTOOPT; 2728 break; 2729 } 2730 break; 2731 2732 case PRCO_GETOPT: 2733 switch (optname) { 2734 case ICMP6_FILTER: 2735 { 2736 if (inp->in6p_icmp6filt == NULL) { 2737 error = EINVAL; 2738 break; 2739 } 2740 error = sooptcopyout(sopt, inp->in6p_icmp6filt, 2741 sizeof(struct icmp6_filter)); 2742 break; 2743 } 2744 2745 default: 2746 error = ENOPROTOOPT; 2747 break; 2748 } 2749 break; 2750 } 2751 2752 return (error); 2753 } 2754 2755 /* 2756 * Perform rate limit check. 2757 * Returns 0 if it is okay to send the icmp6 packet. 2758 * Returns 1 if the router SHOULD NOT send this icmp6 packet due to rate 2759 * limitation. 2760 * 2761 * XXX per-destination/type check necessary? 2762 */ 2763 static int 2764 icmp6_ratelimit(dst, type, code) 2765 const struct in6_addr *dst; /* not used at this moment */ 2766 const int type; /* not used at this moment */ 2767 const int code; /* not used at this moment */ 2768 { 2769 int ret; 2770 2771 ret = 0; /* okay to send */ 2772 2773 /* PPS limit */ 2774 if (!ppsratecheck(&icmp6errppslim_last, &icmp6errpps_count, 2775 icmp6errppslim)) { 2776 /* The packet is subject to rate limit */ 2777 ret++; 2778 } 2779 2780 return ret; 2781 }
Cache object: 996c7372a6822ba1cadcfd80618e98c4
[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]