icmp6.c revision 193744
1193323Sed/*- 2193323Sed * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 3193323Sed * All rights reserved. 4193323Sed * 5193323Sed * Redistribution and use in source and binary forms, with or without 6193323Sed * modification, are permitted provided that the following conditions 7193323Sed * are met: 8193323Sed * 1. Redistributions of source code must retain the above copyright 9193323Sed * notice, this list of conditions and the following disclaimer. 10193323Sed * 2. Redistributions in binary form must reproduce the above copyright 11193323Sed * notice, this list of conditions and the following disclaimer in the 12193323Sed * documentation and/or other materials provided with the distribution. 13193323Sed * 3. Neither the name of the project nor the names of its contributors 14193323Sed * may be used to endorse or promote products derived from this software 15193323Sed * without specific prior written permission. 16193323Sed * 17193323Sed * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 18193323Sed * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19193323Sed * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20193323Sed * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 21193323Sed * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22193323Sed * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23193323Sed * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24193323Sed * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25193323Sed * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26193323Sed * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27193323Sed * SUCH DAMAGE. 28193323Sed * 29193323Sed * $KAME: icmp6.c,v 1.211 2001/04/04 05:56:20 itojun Exp $ 30206083Srdivacky */ 31193323Sed 32193323Sed/*- 33193323Sed * Copyright (c) 1982, 1986, 1988, 1993 34193323Sed * The Regents of the University of California. All rights reserved. 35193323Sed * 36193323Sed * Redistribution and use in source and binary forms, with or without 37193323Sed * modification, are permitted provided that the following conditions 38193323Sed * are met: 39193323Sed * 1. Redistributions of source code must retain the above copyright 40193323Sed * notice, this list of conditions and the following disclaimer. 41193323Sed * 2. Redistributions in binary form must reproduce the above copyright 42193323Sed * notice, this list of conditions and the following disclaimer in the 43193323Sed * documentation and/or other materials provided with the distribution. 44193323Sed * 4. Neither the name of the University nor the names of its contributors 45193323Sed * may be used to endorse or promote products derived from this software 46193323Sed * without specific prior written permission. 47193323Sed * 48193323Sed * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 49193323Sed * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 50193323Sed * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 51193323Sed * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 52193323Sed * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 53193323Sed * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 54193323Sed * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 55193323Sed * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 56193323Sed * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 57193323Sed * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 58193323Sed * SUCH DAMAGE. 59193323Sed * 60193323Sed * @(#)ip_icmp.c 8.2 (Berkeley) 1/4/94 61193323Sed */ 62193323Sed 63193323Sed#include <sys/cdefs.h> 64193323Sed__FBSDID("$FreeBSD: head/sys/netinet6/icmp6.c 193744 2009-06-08 19:57:35Z bz $"); 65193323Sed 66193323Sed#include "opt_inet.h" 67193323Sed#include "opt_inet6.h" 68193323Sed#include "opt_ipsec.h" 69193323Sed 70193323Sed#include <sys/param.h> 71193323Sed#include <sys/domain.h> 72193323Sed#include <sys/jail.h> 73193323Sed#include <sys/kernel.h> 74193323Sed#include <sys/lock.h> 75193323Sed#include <sys/malloc.h> 76193323Sed#include <sys/mbuf.h> 77193323Sed#include <sys/protosw.h> 78193323Sed#include <sys/signalvar.h> 79193323Sed#include <sys/socket.h> 80193323Sed#include <sys/socketvar.h> 81193323Sed#include <sys/sx.h> 82193323Sed#include <sys/syslog.h> 83193323Sed#include <sys/systm.h> 84193323Sed#include <sys/time.h> 85193323Sed#include <sys/vimage.h> 86193323Sed 87193323Sed#include <net/if.h> 88193323Sed#include <net/if_dl.h> 89193323Sed#include <net/if_llatbl.h> 90193323Sed#include <net/if_types.h> 91193323Sed#include <net/route.h> 92193323Sed#include <net/vnet.h> 93193323Sed 94206083Srdivacky#include <netinet/in.h> 95193323Sed#include <netinet/in_pcb.h> 96193323Sed#include <netinet/in_var.h> 97193323Sed#include <netinet/ip6.h> 98193323Sed#include <netinet/icmp6.h> 99193323Sed#include <netinet/tcp_var.h> 100193323Sed#include <netinet/vinet.h> 101193323Sed 102193323Sed#include <netinet6/in6_ifattach.h> 103198090Srdivacky#include <netinet6/in6_pcb.h> 104193323Sed#include <netinet6/ip6protosw.h> 105193323Sed#include <netinet6/ip6_var.h> 106193323Sed#include <netinet6/scope6_var.h> 107193323Sed#include <netinet6/mld6_var.h> 108#include <netinet6/nd6.h> 109#include <netinet6/vinet6.h> 110 111#ifdef IPSEC 112#include <netipsec/ipsec.h> 113#include <netipsec/key.h> 114#endif 115 116extern struct domain inet6domain; 117 118#ifdef VIMAGE_GLOBALS 119extern struct inpcbinfo ripcbinfo; 120extern struct inpcbhead ripcb; 121extern int icmp6errppslim; 122extern int icmp6_nodeinfo; 123 124struct icmp6stat icmp6stat; 125static int icmp6errpps_count; 126static struct timeval icmp6errppslim_last; 127#endif 128 129static void icmp6_errcount(struct icmp6errstat *, int, int); 130static int icmp6_rip6_input(struct mbuf **, int); 131static int icmp6_ratelimit(const struct in6_addr *, const int, const int); 132static const char *icmp6_redirect_diag __P((struct in6_addr *, 133 struct in6_addr *, struct in6_addr *)); 134static struct mbuf *ni6_input(struct mbuf *, int); 135static struct mbuf *ni6_nametodns(const char *, int, int); 136static int ni6_dnsmatch(const char *, int, const char *, int); 137static int ni6_addrs __P((struct icmp6_nodeinfo *, struct mbuf *, 138 struct ifnet **, struct in6_addr *)); 139static int ni6_store_addrs __P((struct icmp6_nodeinfo *, struct icmp6_nodeinfo *, 140 struct ifnet *, int)); 141static int icmp6_notify_error(struct mbuf **, int, int, int); 142 143 144void 145icmp6_init(void) 146{ 147 INIT_VNET_INET6(curvnet); 148 149 V_icmp6errpps_count = 0; 150} 151 152static void 153icmp6_errcount(struct icmp6errstat *stat, int type, int code) 154{ 155 switch (type) { 156 case ICMP6_DST_UNREACH: 157 switch (code) { 158 case ICMP6_DST_UNREACH_NOROUTE: 159 stat->icp6errs_dst_unreach_noroute++; 160 return; 161 case ICMP6_DST_UNREACH_ADMIN: 162 stat->icp6errs_dst_unreach_admin++; 163 return; 164 case ICMP6_DST_UNREACH_BEYONDSCOPE: 165 stat->icp6errs_dst_unreach_beyondscope++; 166 return; 167 case ICMP6_DST_UNREACH_ADDR: 168 stat->icp6errs_dst_unreach_addr++; 169 return; 170 case ICMP6_DST_UNREACH_NOPORT: 171 stat->icp6errs_dst_unreach_noport++; 172 return; 173 } 174 break; 175 case ICMP6_PACKET_TOO_BIG: 176 stat->icp6errs_packet_too_big++; 177 return; 178 case ICMP6_TIME_EXCEEDED: 179 switch (code) { 180 case ICMP6_TIME_EXCEED_TRANSIT: 181 stat->icp6errs_time_exceed_transit++; 182 return; 183 case ICMP6_TIME_EXCEED_REASSEMBLY: 184 stat->icp6errs_time_exceed_reassembly++; 185 return; 186 } 187 break; 188 case ICMP6_PARAM_PROB: 189 switch (code) { 190 case ICMP6_PARAMPROB_HEADER: 191 stat->icp6errs_paramprob_header++; 192 return; 193 case ICMP6_PARAMPROB_NEXTHEADER: 194 stat->icp6errs_paramprob_nextheader++; 195 return; 196 case ICMP6_PARAMPROB_OPTION: 197 stat->icp6errs_paramprob_option++; 198 return; 199 } 200 break; 201 case ND_REDIRECT: 202 stat->icp6errs_redirect++; 203 return; 204 } 205 stat->icp6errs_unknown++; 206} 207 208/* 209 * A wrapper function for icmp6_error() necessary when the erroneous packet 210 * may not contain enough scope zone information. 211 */ 212void 213icmp6_error2(struct mbuf *m, int type, int code, int param, 214 struct ifnet *ifp) 215{ 216 INIT_VNET_INET6(curvnet); 217 struct ip6_hdr *ip6; 218 219 if (ifp == NULL) 220 return; 221 222#ifndef PULLDOWN_TEST 223 IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), ); 224#else 225 if (m->m_len < sizeof(struct ip6_hdr)) { 226 m = m_pullup(m, sizeof(struct ip6_hdr)); 227 if (m == NULL) 228 return; 229 } 230#endif 231 232 ip6 = mtod(m, struct ip6_hdr *); 233 234 if (in6_setscope(&ip6->ip6_src, ifp, NULL) != 0) 235 return; 236 if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0) 237 return; 238 239 icmp6_error(m, type, code, param); 240} 241 242/* 243 * Generate an error packet of type error in response to bad IP6 packet. 244 */ 245void 246icmp6_error(struct mbuf *m, int type, int code, int param) 247{ 248 INIT_VNET_INET6(curvnet); 249 struct ip6_hdr *oip6, *nip6; 250 struct icmp6_hdr *icmp6; 251 u_int preplen; 252 int off; 253 int nxt; 254 255 ICMP6STAT_INC(icp6s_error); 256 257 /* count per-type-code statistics */ 258 icmp6_errcount(&V_icmp6stat.icp6s_outerrhist, type, code); 259 260#ifdef M_DECRYPTED /*not openbsd*/ 261 if (m->m_flags & M_DECRYPTED) { 262 ICMP6STAT_INC(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_INC(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_INC(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_INC(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_INC(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 */ 400int 401icmp6_input(struct mbuf **mp, int *offp, int proto) 402{ 403 INIT_VNET_INET6(curvnet); 404 struct mbuf *m = *mp, *n; 405 struct ifnet *ifp; 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 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 412 413 ifp = m->m_pkthdr.rcvif; 414 415#ifndef PULLDOWN_TEST 416 IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_hdr), IPPROTO_DONE); 417 /* m might change if M_LOOP. So, call mtod after this */ 418#endif 419 420 /* 421 * Locate icmp6 structure in mbuf, and check 422 * that not corrupted and of at least minimum length 423 */ 424 425 ip6 = mtod(m, struct ip6_hdr *); 426 if (icmp6len < sizeof(struct icmp6_hdr)) { 427 ICMP6STAT_INC(icp6s_tooshort); 428 goto freeit; 429 } 430 431 /* 432 * Check multicast group membership. 433 * Note: SSM filters are not applied for ICMPv6 traffic. 434 */ 435 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 436 struct in6_multi *inm; 437 438 inm = in6m_lookup(ifp, &ip6->ip6_dst); 439 if (inm == NULL) { 440 IP6STAT_INC(ip6s_notmember); 441 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 442 goto freeit; 443 } 444 } 445 446 /* 447 * calculate the checksum 448 */ 449#ifndef PULLDOWN_TEST 450 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off); 451#else 452 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 453 if (icmp6 == NULL) { 454 ICMP6STAT_INC(icp6s_tooshort); 455 return IPPROTO_DONE; 456 } 457#endif 458 code = icmp6->icmp6_code; 459 460 if ((sum = in6_cksum(m, IPPROTO_ICMPV6, off, icmp6len)) != 0) { 461 nd6log((LOG_ERR, 462 "ICMP6 checksum error(%d|%x) %s\n", 463 icmp6->icmp6_type, sum, 464 ip6_sprintf(ip6bufs, &ip6->ip6_src))); 465 ICMP6STAT_INC(icp6s_checksum); 466 goto freeit; 467 } 468 469 if (faithprefix_p != NULL && (*faithprefix_p)(&ip6->ip6_dst)) { 470 /* 471 * Deliver very specific ICMP6 type only. 472 * This is important to deliver TOOBIG. Otherwise PMTUD 473 * will not work. 474 */ 475 switch (icmp6->icmp6_type) { 476 case ICMP6_DST_UNREACH: 477 case ICMP6_PACKET_TOO_BIG: 478 case ICMP6_TIME_EXCEEDED: 479 break; 480 default: 481 goto freeit; 482 } 483 } 484 485 ICMP6STAT_INC(icp6s_inhist[icmp6->icmp6_type]); 486 icmp6_ifstat_inc(ifp, ifs6_in_msg); 487 if (icmp6->icmp6_type < ICMP6_INFOMSG_MASK) 488 icmp6_ifstat_inc(ifp, ifs6_in_error); 489 490 switch (icmp6->icmp6_type) { 491 case ICMP6_DST_UNREACH: 492 icmp6_ifstat_inc(ifp, ifs6_in_dstunreach); 493 switch (code) { 494 case ICMP6_DST_UNREACH_NOROUTE: 495 code = PRC_UNREACH_NET; 496 break; 497 case ICMP6_DST_UNREACH_ADMIN: 498 icmp6_ifstat_inc(ifp, ifs6_in_adminprohib); 499 code = PRC_UNREACH_PROTOCOL; /* is this a good code? */ 500 break; 501 case ICMP6_DST_UNREACH_ADDR: 502 code = PRC_HOSTDEAD; 503 break; 504 case ICMP6_DST_UNREACH_BEYONDSCOPE: 505 /* I mean "source address was incorrect." */ 506 code = PRC_PARAMPROB; 507 break; 508 case ICMP6_DST_UNREACH_NOPORT: 509 code = PRC_UNREACH_PORT; 510 break; 511 default: 512 goto badcode; 513 } 514 goto deliver; 515 break; 516 517 case ICMP6_PACKET_TOO_BIG: 518 icmp6_ifstat_inc(ifp, ifs6_in_pkttoobig); 519 520 /* validation is made in icmp6_mtudisc_update */ 521 522 code = PRC_MSGSIZE; 523 524 /* 525 * Updating the path MTU will be done after examining 526 * intermediate extension headers. 527 */ 528 goto deliver; 529 break; 530 531 case ICMP6_TIME_EXCEEDED: 532 icmp6_ifstat_inc(ifp, ifs6_in_timeexceed); 533 switch (code) { 534 case ICMP6_TIME_EXCEED_TRANSIT: 535 code = PRC_TIMXCEED_INTRANS; 536 break; 537 case ICMP6_TIME_EXCEED_REASSEMBLY: 538 code = PRC_TIMXCEED_REASS; 539 break; 540 default: 541 goto badcode; 542 } 543 goto deliver; 544 break; 545 546 case ICMP6_PARAM_PROB: 547 icmp6_ifstat_inc(ifp, ifs6_in_paramprob); 548 switch (code) { 549 case ICMP6_PARAMPROB_NEXTHEADER: 550 code = PRC_UNREACH_PROTOCOL; 551 break; 552 case ICMP6_PARAMPROB_HEADER: 553 case ICMP6_PARAMPROB_OPTION: 554 code = PRC_PARAMPROB; 555 break; 556 default: 557 goto badcode; 558 } 559 goto deliver; 560 break; 561 562 case ICMP6_ECHO_REQUEST: 563 icmp6_ifstat_inc(ifp, ifs6_in_echo); 564 if (code != 0) 565 goto badcode; 566 if ((n = m_copy(m, 0, M_COPYALL)) == NULL) { 567 /* Give up remote */ 568 break; 569 } 570 if ((n->m_flags & M_EXT) != 0 571 || n->m_len < off + sizeof(struct icmp6_hdr)) { 572 struct mbuf *n0 = n; 573 const int maxlen = sizeof(*nip6) + sizeof(*nicmp6); 574 int n0len; 575 576 MGETHDR(n, M_DONTWAIT, n0->m_type); 577 n0len = n0->m_pkthdr.len; /* save for use below */ 578 if (n) 579 M_MOVE_PKTHDR(n, n0); 580 if (n && maxlen >= MHLEN) { 581 MCLGET(n, M_DONTWAIT); 582 if ((n->m_flags & M_EXT) == 0) { 583 m_free(n); 584 n = NULL; 585 } 586 } 587 if (n == NULL) { 588 /* Give up remote */ 589 m_freem(n0); 590 break; 591 } 592 /* 593 * Copy IPv6 and ICMPv6 only. 594 */ 595 nip6 = mtod(n, struct ip6_hdr *); 596 bcopy(ip6, nip6, sizeof(struct ip6_hdr)); 597 nicmp6 = (struct icmp6_hdr *)(nip6 + 1); 598 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr)); 599 noff = sizeof(struct ip6_hdr); 600 /* new mbuf contains only ipv6+icmpv6 headers */ 601 n->m_len = noff + sizeof(struct icmp6_hdr); 602 /* 603 * Adjust mbuf. ip6_plen will be adjusted in 604 * ip6_output(). 605 */ 606 m_adj(n0, off + sizeof(struct icmp6_hdr)); 607 /* recalculate complete packet size */ 608 n->m_pkthdr.len = n0len + (noff - off); 609 n->m_next = n0; 610 } else { 611 nip6 = mtod(n, struct ip6_hdr *); 612 IP6_EXTHDR_GET(nicmp6, struct icmp6_hdr *, n, off, 613 sizeof(*nicmp6)); 614 noff = off; 615 } 616 nicmp6->icmp6_type = ICMP6_ECHO_REPLY; 617 nicmp6->icmp6_code = 0; 618 if (n) { 619 ICMP6STAT_INC(icp6s_reflect); 620 ICMP6STAT_INC(icp6s_outhist[ICMP6_ECHO_REPLY]); 621 icmp6_reflect(n, noff); 622 } 623 break; 624 625 case ICMP6_ECHO_REPLY: 626 icmp6_ifstat_inc(ifp, ifs6_in_echoreply); 627 if (code != 0) 628 goto badcode; 629 break; 630 631 case MLD_LISTENER_QUERY: 632 case MLD_LISTENER_REPORT: 633 case MLD_LISTENER_DONE: 634 case MLDV2_LISTENER_REPORT: 635 /* 636 * Drop MLD traffic which is not link-local, has a hop limit 637 * of greater than 1 hop, or which does not have the 638 * IPv6 HBH Router Alert option. 639 * As IPv6 HBH options are stripped in ip6_input() we must 640 * check an mbuf header flag. 641 * XXX Should we also sanity check that these messages 642 * were directed to a link-local multicast prefix? 643 */ 644 if ((ip6->ip6_hlim != 1) || (m->m_flags & M_RTALERT_MLD) == 0) 645 goto freeit; 646 if (mld_input(m, off, icmp6len) != 0) 647 return (IPPROTO_DONE); 648 /* m stays. */ 649 break; 650 651 case ICMP6_WRUREQUEST: /* ICMP6_FQDN_QUERY */ 652 { 653 enum { WRU, FQDN } mode; 654 655 if (!V_icmp6_nodeinfo) 656 break; 657 658 if (icmp6len == sizeof(struct icmp6_hdr) + 4) 659 mode = WRU; 660 else if (icmp6len >= sizeof(struct icmp6_nodeinfo)) 661 mode = FQDN; 662 else 663 goto badlen; 664 665 if (mode == FQDN) { 666#ifndef PULLDOWN_TEST 667 IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_nodeinfo), 668 IPPROTO_DONE); 669#endif 670 n = m_copy(m, 0, M_COPYALL); 671 if (n) 672 n = ni6_input(n, off); 673 /* XXX meaningless if n == NULL */ 674 noff = sizeof(struct ip6_hdr); 675 } else { 676 struct prison *pr; 677 u_char *p; 678 int maxlen, maxhlen, hlen; 679 680 /* 681 * XXX: this combination of flags is pointless, 682 * but should we keep this for compatibility? 683 */ 684 if ((V_icmp6_nodeinfo & 5) != 5) 685 break; 686 687 if (code != 0) 688 goto badcode; 689 maxlen = sizeof(*nip6) + sizeof(*nicmp6) + 4; 690 if (maxlen >= MCLBYTES) { 691 /* Give up remote */ 692 break; 693 } 694 MGETHDR(n, M_DONTWAIT, m->m_type); 695 if (n && maxlen > MHLEN) { 696 MCLGET(n, M_DONTWAIT); 697 if ((n->m_flags & M_EXT) == 0) { 698 m_free(n); 699 n = NULL; 700 } 701 } 702 if (n && !m_dup_pkthdr(n, m, M_DONTWAIT)) { 703 /* 704 * Previous code did a blind M_COPY_PKTHDR 705 * and said "just for rcvif". If true, then 706 * we could tolerate the dup failing (due to 707 * the deep copy of the tag chain). For now 708 * be conservative and just fail. 709 */ 710 m_free(n); 711 n = NULL; 712 } 713 if (n == NULL) { 714 /* Give up remote */ 715 break; 716 } 717 n->m_pkthdr.rcvif = NULL; 718 n->m_len = 0; 719 maxhlen = M_TRAILINGSPACE(n) - maxlen; 720 pr = curthread->td_ucred->cr_prison; 721 mtx_lock(&pr->pr_mtx); 722 hlen = strlen(pr->pr_host); 723 if (maxhlen > hlen) 724 maxhlen = hlen; 725 /* 726 * Copy IPv6 and ICMPv6 only. 727 */ 728 nip6 = mtod(n, struct ip6_hdr *); 729 bcopy(ip6, nip6, sizeof(struct ip6_hdr)); 730 nicmp6 = (struct icmp6_hdr *)(nip6 + 1); 731 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr)); 732 p = (u_char *)(nicmp6 + 1); 733 bzero(p, 4); 734 bcopy(pr->pr_host, p + 4, maxhlen); /* meaningless TTL */ 735 mtx_unlock(&pr->pr_mtx); 736 noff = sizeof(struct ip6_hdr); 737 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) + 738 sizeof(struct icmp6_hdr) + 4 + maxhlen; 739 nicmp6->icmp6_type = ICMP6_WRUREPLY; 740 nicmp6->icmp6_code = 0; 741 } 742 if (n) { 743 ICMP6STAT_INC(icp6s_reflect); 744 ICMP6STAT_INC(icp6s_outhist[ICMP6_WRUREPLY]); 745 icmp6_reflect(n, noff); 746 } 747 break; 748 } 749 750 case ICMP6_WRUREPLY: 751 if (code != 0) 752 goto badcode; 753 break; 754 755 case ND_ROUTER_SOLICIT: 756 icmp6_ifstat_inc(ifp, ifs6_in_routersolicit); 757 if (code != 0) 758 goto badcode; 759 if (icmp6len < sizeof(struct nd_router_solicit)) 760 goto badlen; 761 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 762 /* give up local */ 763 nd6_rs_input(m, off, icmp6len); 764 m = NULL; 765 goto freeit; 766 } 767 nd6_rs_input(n, off, icmp6len); 768 /* m stays. */ 769 break; 770 771 case ND_ROUTER_ADVERT: 772 icmp6_ifstat_inc(ifp, ifs6_in_routeradvert); 773 if (code != 0) 774 goto badcode; 775 if (icmp6len < sizeof(struct nd_router_advert)) 776 goto badlen; 777 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 778 /* give up local */ 779 nd6_ra_input(m, off, icmp6len); 780 m = NULL; 781 goto freeit; 782 } 783 nd6_ra_input(n, off, icmp6len); 784 /* m stays. */ 785 break; 786 787 case ND_NEIGHBOR_SOLICIT: 788 icmp6_ifstat_inc(ifp, ifs6_in_neighborsolicit); 789 if (code != 0) 790 goto badcode; 791 if (icmp6len < sizeof(struct nd_neighbor_solicit)) 792 goto badlen; 793 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 794 /* give up local */ 795 nd6_ns_input(m, off, icmp6len); 796 m = NULL; 797 goto freeit; 798 } 799 nd6_ns_input(n, off, icmp6len); 800 /* m stays. */ 801 break; 802 803 case ND_NEIGHBOR_ADVERT: 804 icmp6_ifstat_inc(ifp, ifs6_in_neighboradvert); 805 if (code != 0) 806 goto badcode; 807 if (icmp6len < sizeof(struct nd_neighbor_advert)) 808 goto badlen; 809 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 810 /* give up local */ 811 nd6_na_input(m, off, icmp6len); 812 m = NULL; 813 goto freeit; 814 } 815 nd6_na_input(n, off, icmp6len); 816 /* m stays. */ 817 break; 818 819 case ND_REDIRECT: 820 icmp6_ifstat_inc(ifp, ifs6_in_redirect); 821 if (code != 0) 822 goto badcode; 823 if (icmp6len < sizeof(struct nd_redirect)) 824 goto badlen; 825 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 826 /* give up local */ 827 icmp6_redirect_input(m, off); 828 m = NULL; 829 goto freeit; 830 } 831 icmp6_redirect_input(n, off); 832 /* m stays. */ 833 break; 834 835 case ICMP6_ROUTER_RENUMBERING: 836 if (code != ICMP6_ROUTER_RENUMBERING_COMMAND && 837 code != ICMP6_ROUTER_RENUMBERING_RESULT) 838 goto badcode; 839 if (icmp6len < sizeof(struct icmp6_router_renum)) 840 goto badlen; 841 break; 842 843 default: 844 nd6log((LOG_DEBUG, 845 "icmp6_input: unknown type %d(src=%s, dst=%s, ifid=%d)\n", 846 icmp6->icmp6_type, ip6_sprintf(ip6bufs, &ip6->ip6_src), 847 ip6_sprintf(ip6bufd, &ip6->ip6_dst), 848 ifp ? ifp->if_index : 0)); 849 if (icmp6->icmp6_type < ICMP6_ECHO_REQUEST) { 850 /* ICMPv6 error: MUST deliver it by spec... */ 851 code = PRC_NCMDS; 852 /* deliver */ 853 } else { 854 /* ICMPv6 informational: MUST not deliver */ 855 break; 856 } 857 deliver: 858 if (icmp6_notify_error(&m, off, icmp6len, code)) { 859 /* In this case, m should've been freed. */ 860 return (IPPROTO_DONE); 861 } 862 break; 863 864 badcode: 865 ICMP6STAT_INC(icp6s_badcode); 866 break; 867 868 badlen: 869 ICMP6STAT_INC(icp6s_badlen); 870 break; 871 } 872 873 /* deliver the packet to appropriate sockets */ 874 icmp6_rip6_input(&m, *offp); 875 876 return IPPROTO_DONE; 877 878 freeit: 879 m_freem(m); 880 return IPPROTO_DONE; 881} 882 883static int 884icmp6_notify_error(struct mbuf **mp, int off, int icmp6len, int code) 885{ 886 INIT_VNET_INET6(curvnet); 887 struct mbuf *m = *mp; 888 struct icmp6_hdr *icmp6; 889 struct ip6_hdr *eip6; 890 u_int32_t notifymtu; 891 struct sockaddr_in6 icmp6src, icmp6dst; 892 893 if (icmp6len < sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr)) { 894 ICMP6STAT_INC(icp6s_tooshort); 895 goto freeit; 896 } 897#ifndef PULLDOWN_TEST 898 IP6_EXTHDR_CHECK(m, off, 899 sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr), -1); 900 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 901#else 902 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, 903 sizeof(*icmp6) + sizeof(struct ip6_hdr)); 904 if (icmp6 == NULL) { 905 ICMP6STAT_INC(icp6s_tooshort); 906 return (-1); 907 } 908#endif 909 eip6 = (struct ip6_hdr *)(icmp6 + 1); 910 911 /* Detect the upper level protocol */ 912 { 913 void (*ctlfunc)(int, struct sockaddr *, void *); 914 u_int8_t nxt = eip6->ip6_nxt; 915 int eoff = off + sizeof(struct icmp6_hdr) + 916 sizeof(struct ip6_hdr); 917 struct ip6ctlparam ip6cp; 918 struct in6_addr *finaldst = NULL; 919 int icmp6type = icmp6->icmp6_type; 920 struct ip6_frag *fh; 921 struct ip6_rthdr *rth; 922 struct ip6_rthdr0 *rth0; 923 int rthlen; 924 925 while (1) { /* XXX: should avoid infinite loop explicitly? */ 926 struct ip6_ext *eh; 927 928 switch (nxt) { 929 case IPPROTO_HOPOPTS: 930 case IPPROTO_DSTOPTS: 931 case IPPROTO_AH: 932#ifndef PULLDOWN_TEST 933 IP6_EXTHDR_CHECK(m, 0, 934 eoff + sizeof(struct ip6_ext), -1); 935 eh = (struct ip6_ext *)(mtod(m, caddr_t) + eoff); 936#else 937 IP6_EXTHDR_GET(eh, struct ip6_ext *, m, 938 eoff, sizeof(*eh)); 939 if (eh == NULL) { 940 ICMP6STAT_INC(icp6s_tooshort); 941 return (-1); 942 } 943#endif 944 945 if (nxt == IPPROTO_AH) 946 eoff += (eh->ip6e_len + 2) << 2; 947 else 948 eoff += (eh->ip6e_len + 1) << 3; 949 nxt = eh->ip6e_nxt; 950 break; 951 case IPPROTO_ROUTING: 952 /* 953 * When the erroneous packet contains a 954 * routing header, we should examine the 955 * header to determine the final destination. 956 * Otherwise, we can't properly update 957 * information that depends on the final 958 * destination (e.g. path MTU). 959 */ 960#ifndef PULLDOWN_TEST 961 IP6_EXTHDR_CHECK(m, 0, eoff + sizeof(*rth), -1); 962 rth = (struct ip6_rthdr *) 963 (mtod(m, caddr_t) + eoff); 964#else 965 IP6_EXTHDR_GET(rth, struct ip6_rthdr *, m, 966 eoff, sizeof(*rth)); 967 if (rth == NULL) { 968 ICMP6STAT_INC(icp6s_tooshort); 969 return (-1); 970 } 971#endif 972 rthlen = (rth->ip6r_len + 1) << 3; 973 /* 974 * XXX: currently there is no 975 * officially defined type other 976 * than type-0. 977 * Note that if the segment left field 978 * is 0, all intermediate hops must 979 * have been passed. 980 */ 981 if (rth->ip6r_segleft && 982 rth->ip6r_type == IPV6_RTHDR_TYPE_0) { 983 int hops; 984 985#ifndef PULLDOWN_TEST 986 IP6_EXTHDR_CHECK(m, 0, eoff + rthlen, -1); 987 rth0 = (struct ip6_rthdr0 *) 988 (mtod(m, caddr_t) + eoff); 989#else 990 IP6_EXTHDR_GET(rth0, 991 struct ip6_rthdr0 *, m, 992 eoff, rthlen); 993 if (rth0 == NULL) { 994 ICMP6STAT_INC(icp6s_tooshort); 995 return (-1); 996 } 997#endif 998 /* just ignore a bogus header */ 999 if ((rth0->ip6r0_len % 2) == 0 && 1000 (hops = rth0->ip6r0_len/2)) 1001 finaldst = (struct in6_addr *)(rth0 + 1) + (hops - 1); 1002 } 1003 eoff += rthlen; 1004 nxt = rth->ip6r_nxt; 1005 break; 1006 case IPPROTO_FRAGMENT: 1007#ifndef PULLDOWN_TEST 1008 IP6_EXTHDR_CHECK(m, 0, eoff + 1009 sizeof(struct ip6_frag), -1); 1010 fh = (struct ip6_frag *)(mtod(m, caddr_t) + 1011 eoff); 1012#else 1013 IP6_EXTHDR_GET(fh, struct ip6_frag *, m, 1014 eoff, sizeof(*fh)); 1015 if (fh == NULL) { 1016 ICMP6STAT_INC(icp6s_tooshort); 1017 return (-1); 1018 } 1019#endif 1020 /* 1021 * Data after a fragment header is meaningless 1022 * unless it is the first fragment, but 1023 * we'll go to the notify label for path MTU 1024 * discovery. 1025 */ 1026 if (fh->ip6f_offlg & IP6F_OFF_MASK) 1027 goto notify; 1028 1029 eoff += sizeof(struct ip6_frag); 1030 nxt = fh->ip6f_nxt; 1031 break; 1032 default: 1033 /* 1034 * This case includes ESP and the No Next 1035 * Header. In such cases going to the notify 1036 * label does not have any meaning 1037 * (i.e. ctlfunc will be NULL), but we go 1038 * anyway since we might have to update 1039 * path MTU information. 1040 */ 1041 goto notify; 1042 } 1043 } 1044 notify: 1045#ifndef PULLDOWN_TEST 1046 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 1047#else 1048 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, 1049 sizeof(*icmp6) + sizeof(struct ip6_hdr)); 1050 if (icmp6 == NULL) { 1051 ICMP6STAT_INC(icp6s_tooshort); 1052 return (-1); 1053 } 1054#endif 1055 1056 /* 1057 * retrieve parameters from the inner IPv6 header, and convert 1058 * them into sockaddr structures. 1059 * XXX: there is no guarantee that the source or destination 1060 * addresses of the inner packet are in the same scope as 1061 * the addresses of the icmp packet. But there is no other 1062 * way to determine the zone. 1063 */ 1064 eip6 = (struct ip6_hdr *)(icmp6 + 1); 1065 1066 bzero(&icmp6dst, sizeof(icmp6dst)); 1067 icmp6dst.sin6_len = sizeof(struct sockaddr_in6); 1068 icmp6dst.sin6_family = AF_INET6; 1069 if (finaldst == NULL) 1070 icmp6dst.sin6_addr = eip6->ip6_dst; 1071 else 1072 icmp6dst.sin6_addr = *finaldst; 1073 if (in6_setscope(&icmp6dst.sin6_addr, m->m_pkthdr.rcvif, NULL)) 1074 goto freeit; 1075 bzero(&icmp6src, sizeof(icmp6src)); 1076 icmp6src.sin6_len = sizeof(struct sockaddr_in6); 1077 icmp6src.sin6_family = AF_INET6; 1078 icmp6src.sin6_addr = eip6->ip6_src; 1079 if (in6_setscope(&icmp6src.sin6_addr, m->m_pkthdr.rcvif, NULL)) 1080 goto freeit; 1081 icmp6src.sin6_flowinfo = 1082 (eip6->ip6_flow & IPV6_FLOWLABEL_MASK); 1083 1084 if (finaldst == NULL) 1085 finaldst = &eip6->ip6_dst; 1086 ip6cp.ip6c_m = m; 1087 ip6cp.ip6c_icmp6 = icmp6; 1088 ip6cp.ip6c_ip6 = (struct ip6_hdr *)(icmp6 + 1); 1089 ip6cp.ip6c_off = eoff; 1090 ip6cp.ip6c_finaldst = finaldst; 1091 ip6cp.ip6c_src = &icmp6src; 1092 ip6cp.ip6c_nxt = nxt; 1093 1094 if (icmp6type == ICMP6_PACKET_TOO_BIG) { 1095 notifymtu = ntohl(icmp6->icmp6_mtu); 1096 ip6cp.ip6c_cmdarg = (void *)¬ifymtu; 1097 icmp6_mtudisc_update(&ip6cp, 1); /*XXX*/ 1098 } 1099 1100 ctlfunc = (void (*)(int, struct sockaddr *, void *)) 1101 (inet6sw[ip6_protox[nxt]].pr_ctlinput); 1102 if (ctlfunc) { 1103 (void) (*ctlfunc)(code, (struct sockaddr *)&icmp6dst, 1104 &ip6cp); 1105 } 1106 } 1107 *mp = m; 1108 return (0); 1109 1110 freeit: 1111 m_freem(m); 1112 return (-1); 1113} 1114 1115void 1116icmp6_mtudisc_update(struct ip6ctlparam *ip6cp, int validated) 1117{ 1118 INIT_VNET_INET6(curvnet); 1119 struct in6_addr *dst = ip6cp->ip6c_finaldst; 1120 struct icmp6_hdr *icmp6 = ip6cp->ip6c_icmp6; 1121 struct mbuf *m = ip6cp->ip6c_m; /* will be necessary for scope issue */ 1122 u_int mtu = ntohl(icmp6->icmp6_mtu); 1123 struct in_conninfo inc; 1124 1125#if 0 1126 /* 1127 * RFC2460 section 5, last paragraph. 1128 * even though minimum link MTU for IPv6 is IPV6_MMTU, 1129 * we may see ICMPv6 too big with mtu < IPV6_MMTU 1130 * due to packet translator in the middle. 1131 * see ip6_output() and ip6_getpmtu() "alwaysfrag" case for 1132 * special handling. 1133 */ 1134 if (mtu < IPV6_MMTU) 1135 return; 1136#endif 1137 1138 /* 1139 * we reject ICMPv6 too big with abnormally small value. 1140 * XXX what is the good definition of "abnormally small"? 1141 */ 1142 if (mtu < sizeof(struct ip6_hdr) + sizeof(struct ip6_frag) + 8) 1143 return; 1144 1145 if (!validated) 1146 return; 1147 1148 /* 1149 * In case the suggested mtu is less than IPV6_MMTU, we 1150 * only need to remember that it was for above mentioned 1151 * "alwaysfrag" case. 1152 * Try to be as close to the spec as possible. 1153 */ 1154 if (mtu < IPV6_MMTU) 1155 mtu = IPV6_MMTU - 8; 1156 1157 bzero(&inc, sizeof(inc)); 1158 inc.inc_flags |= INC_ISIPV6; 1159 inc.inc6_faddr = *dst; 1160 if (in6_setscope(&inc.inc6_faddr, m->m_pkthdr.rcvif, NULL)) 1161 return; 1162 1163 if (mtu < tcp_maxmtu6(&inc, NULL)) { 1164 tcp_hc_updatemtu(&inc, mtu); 1165 ICMP6STAT_INC(icp6s_pmtuchg); 1166 } 1167} 1168 1169/* 1170 * Process a Node Information Query packet, based on 1171 * draft-ietf-ipngwg-icmp-name-lookups-07. 1172 * 1173 * Spec incompatibilities: 1174 * - IPv6 Subject address handling 1175 * - IPv4 Subject address handling support missing 1176 * - Proxy reply (answer even if it's not for me) 1177 * - joins NI group address at in6_ifattach() time only, does not cope 1178 * with hostname changes by sethostname(3) 1179 */ 1180static struct mbuf * 1181ni6_input(struct mbuf *m, int off) 1182{ 1183 INIT_VNET_INET6(curvnet); 1184 struct icmp6_nodeinfo *ni6, *nni6; 1185 struct mbuf *n = NULL; 1186 struct prison *pr; 1187 u_int16_t qtype; 1188 int subjlen; 1189 int replylen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo); 1190 struct ni_reply_fqdn *fqdn; 1191 int addrs; /* for NI_QTYPE_NODEADDR */ 1192 struct ifnet *ifp = NULL; /* for NI_QTYPE_NODEADDR */ 1193 struct in6_addr in6_subj; /* subject address */ 1194 struct ip6_hdr *ip6; 1195 int oldfqdn = 0; /* if 1, return pascal string (03 draft) */ 1196 char *subj = NULL; 1197 struct in6_ifaddr *ia6 = NULL; 1198 1199 ip6 = mtod(m, struct ip6_hdr *); 1200#ifndef PULLDOWN_TEST 1201 ni6 = (struct icmp6_nodeinfo *)(mtod(m, caddr_t) + off); 1202#else 1203 IP6_EXTHDR_GET(ni6, struct icmp6_nodeinfo *, m, off, sizeof(*ni6)); 1204 if (ni6 == NULL) { 1205 /* m is already reclaimed */ 1206 return (NULL); 1207 } 1208#endif 1209 1210 /* 1211 * Validate IPv6 source address. 1212 * The default configuration MUST be to refuse answering queries from 1213 * global-scope addresses according to RFC4602. 1214 * Notes: 1215 * - it's not very clear what "refuse" means; this implementation 1216 * simply drops it. 1217 * - it's not very easy to identify global-scope (unicast) addresses 1218 * since there are many prefixes for them. It should be safer 1219 * and in practice sufficient to check "all" but loopback and 1220 * link-local (note that site-local unicast was deprecated and 1221 * ULA is defined as global scope-wise) 1222 */ 1223 if ((V_icmp6_nodeinfo & ICMP6_NODEINFO_GLOBALOK) == 0 && 1224 !IN6_IS_ADDR_LOOPBACK(&ip6->ip6_src) && 1225 !IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_src)) 1226 goto bad; 1227 1228 /* 1229 * Validate IPv6 destination address. 1230 * 1231 * The Responder must discard the Query without further processing 1232 * unless it is one of the Responder's unicast or anycast addresses, or 1233 * a link-local scope multicast address which the Responder has joined. 1234 * [RFC4602, Section 5.] 1235 */ 1236 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 1237 if (!IN6_IS_ADDR_MC_LINKLOCAL(&ip6->ip6_dst)) 1238 goto bad; 1239 /* else it's a link-local multicast, fine */ 1240 } else { /* unicast or anycast */ 1241 if ((ia6 = ip6_getdstifaddr(m)) == NULL) 1242 goto bad; /* XXX impossible */ 1243 1244 if ((ia6->ia6_flags & IN6_IFF_TEMPORARY) && 1245 !(V_icmp6_nodeinfo & ICMP6_NODEINFO_TMPADDROK)) { 1246 nd6log((LOG_DEBUG, "ni6_input: ignore node info to " 1247 "a temporary address in %s:%d", 1248 __FILE__, __LINE__)); 1249 goto bad; 1250 } 1251 } 1252 1253 /* validate query Subject field. */ 1254 qtype = ntohs(ni6->ni_qtype); 1255 subjlen = m->m_pkthdr.len - off - sizeof(struct icmp6_nodeinfo); 1256 switch (qtype) { 1257 case NI_QTYPE_NOOP: 1258 case NI_QTYPE_SUPTYPES: 1259 /* 07 draft */ 1260 if (ni6->ni_code == ICMP6_NI_SUBJ_FQDN && subjlen == 0) 1261 break; 1262 /* FALLTHROUGH */ 1263 case NI_QTYPE_FQDN: 1264 case NI_QTYPE_NODEADDR: 1265 case NI_QTYPE_IPV4ADDR: 1266 switch (ni6->ni_code) { 1267 case ICMP6_NI_SUBJ_IPV6: 1268#if ICMP6_NI_SUBJ_IPV6 != 0 1269 case 0: 1270#endif 1271 /* 1272 * backward compatibility - try to accept 03 draft 1273 * format, where no Subject is present. 1274 */ 1275 if (qtype == NI_QTYPE_FQDN && ni6->ni_code == 0 && 1276 subjlen == 0) { 1277 oldfqdn++; 1278 break; 1279 } 1280#if ICMP6_NI_SUBJ_IPV6 != 0 1281 if (ni6->ni_code != ICMP6_NI_SUBJ_IPV6) 1282 goto bad; 1283#endif 1284 1285 if (subjlen != sizeof(struct in6_addr)) 1286 goto bad; 1287 1288 /* 1289 * Validate Subject address. 1290 * 1291 * Not sure what exactly "address belongs to the node" 1292 * means in the spec, is it just unicast, or what? 1293 * 1294 * At this moment we consider Subject address as 1295 * "belong to the node" if the Subject address equals 1296 * to the IPv6 destination address; validation for 1297 * IPv6 destination address should have done enough 1298 * check for us. 1299 * 1300 * We do not do proxy at this moment. 1301 */ 1302 /* m_pulldown instead of copy? */ 1303 m_copydata(m, off + sizeof(struct icmp6_nodeinfo), 1304 subjlen, (caddr_t)&in6_subj); 1305 if (in6_setscope(&in6_subj, m->m_pkthdr.rcvif, NULL)) 1306 goto bad; 1307 1308 subj = (char *)&in6_subj; 1309 if (IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, &in6_subj)) 1310 break; 1311 1312 /* 1313 * XXX if we are to allow other cases, we should really 1314 * be careful about scope here. 1315 * basically, we should disallow queries toward IPv6 1316 * destination X with subject Y, 1317 * if scope(X) > scope(Y). 1318 * if we allow scope(X) > scope(Y), it will result in 1319 * information leakage across scope boundary. 1320 */ 1321 goto bad; 1322 1323 case ICMP6_NI_SUBJ_FQDN: 1324 /* 1325 * Validate Subject name with gethostname(3). 1326 * 1327 * The behavior may need some debate, since: 1328 * - we are not sure if the node has FQDN as 1329 * hostname (returned by gethostname(3)). 1330 * - the code does wildcard match for truncated names. 1331 * however, we are not sure if we want to perform 1332 * wildcard match, if gethostname(3) side has 1333 * truncated hostname. 1334 */ 1335 pr = curthread->td_ucred->cr_prison; 1336 mtx_lock(&pr->pr_mtx); 1337 n = ni6_nametodns(pr->pr_host, strlen(pr->pr_host), 0); 1338 mtx_unlock(&pr->pr_mtx); 1339 if (!n || n->m_next || n->m_len == 0) 1340 goto bad; 1341 IP6_EXTHDR_GET(subj, char *, m, 1342 off + sizeof(struct icmp6_nodeinfo), subjlen); 1343 if (subj == NULL) 1344 goto bad; 1345 if (!ni6_dnsmatch(subj, subjlen, mtod(n, const char *), 1346 n->m_len)) { 1347 goto bad; 1348 } 1349 m_freem(n); 1350 n = NULL; 1351 break; 1352 1353 case ICMP6_NI_SUBJ_IPV4: /* XXX: to be implemented? */ 1354 default: 1355 goto bad; 1356 } 1357 break; 1358 } 1359 1360 /* refuse based on configuration. XXX ICMP6_NI_REFUSED? */ 1361 switch (qtype) { 1362 case NI_QTYPE_FQDN: 1363 if ((V_icmp6_nodeinfo & ICMP6_NODEINFO_FQDNOK) == 0) 1364 goto bad; 1365 break; 1366 case NI_QTYPE_NODEADDR: 1367 case NI_QTYPE_IPV4ADDR: 1368 if ((V_icmp6_nodeinfo & ICMP6_NODEINFO_NODEADDROK) == 0) 1369 goto bad; 1370 break; 1371 } 1372 1373 /* guess reply length */ 1374 switch (qtype) { 1375 case NI_QTYPE_NOOP: 1376 break; /* no reply data */ 1377 case NI_QTYPE_SUPTYPES: 1378 replylen += sizeof(u_int32_t); 1379 break; 1380 case NI_QTYPE_FQDN: 1381 /* XXX will append an mbuf */ 1382 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1383 break; 1384 case NI_QTYPE_NODEADDR: 1385 addrs = ni6_addrs(ni6, m, &ifp, (struct in6_addr *)subj); 1386 if ((replylen += addrs * (sizeof(struct in6_addr) + 1387 sizeof(u_int32_t))) > MCLBYTES) 1388 replylen = MCLBYTES; /* XXX: will truncate pkt later */ 1389 break; 1390 case NI_QTYPE_IPV4ADDR: 1391 /* unsupported - should respond with unknown Qtype? */ 1392 break; 1393 default: 1394 /* 1395 * XXX: We must return a reply with the ICMP6 code 1396 * `unknown Qtype' in this case. However we regard the case 1397 * as an FQDN query for backward compatibility. 1398 * Older versions set a random value to this field, 1399 * so it rarely varies in the defined qtypes. 1400 * But the mechanism is not reliable... 1401 * maybe we should obsolete older versions. 1402 */ 1403 qtype = NI_QTYPE_FQDN; 1404 /* XXX will append an mbuf */ 1405 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1406 oldfqdn++; 1407 break; 1408 } 1409 1410 /* allocate an mbuf to reply. */ 1411 MGETHDR(n, M_DONTWAIT, m->m_type); 1412 if (n == NULL) { 1413 m_freem(m); 1414 return (NULL); 1415 } 1416 M_MOVE_PKTHDR(n, m); /* just for recvif */ 1417 if (replylen > MHLEN) { 1418 if (replylen > MCLBYTES) { 1419 /* 1420 * XXX: should we try to allocate more? But MCLBYTES 1421 * is probably much larger than IPV6_MMTU... 1422 */ 1423 goto bad; 1424 } 1425 MCLGET(n, M_DONTWAIT); 1426 if ((n->m_flags & M_EXT) == 0) { 1427 goto bad; 1428 } 1429 } 1430 n->m_pkthdr.len = n->m_len = replylen; 1431 1432 /* copy mbuf header and IPv6 + Node Information base headers */ 1433 bcopy(mtod(m, caddr_t), mtod(n, caddr_t), sizeof(struct ip6_hdr)); 1434 nni6 = (struct icmp6_nodeinfo *)(mtod(n, struct ip6_hdr *) + 1); 1435 bcopy((caddr_t)ni6, (caddr_t)nni6, sizeof(struct icmp6_nodeinfo)); 1436 1437 /* qtype dependent procedure */ 1438 switch (qtype) { 1439 case NI_QTYPE_NOOP: 1440 nni6->ni_code = ICMP6_NI_SUCCESS; 1441 nni6->ni_flags = 0; 1442 break; 1443 case NI_QTYPE_SUPTYPES: 1444 { 1445 u_int32_t v; 1446 nni6->ni_code = ICMP6_NI_SUCCESS; 1447 nni6->ni_flags = htons(0x0000); /* raw bitmap */ 1448 /* supports NOOP, SUPTYPES, FQDN, and NODEADDR */ 1449 v = (u_int32_t)htonl(0x0000000f); 1450 bcopy(&v, nni6 + 1, sizeof(u_int32_t)); 1451 break; 1452 } 1453 case NI_QTYPE_FQDN: 1454 nni6->ni_code = ICMP6_NI_SUCCESS; 1455 fqdn = (struct ni_reply_fqdn *)(mtod(n, caddr_t) + 1456 sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo)); 1457 nni6->ni_flags = 0; /* XXX: meaningless TTL */ 1458 fqdn->ni_fqdn_ttl = 0; /* ditto. */ 1459 /* 1460 * XXX do we really have FQDN in hostname? 1461 */ 1462 pr = curthread->td_ucred->cr_prison; 1463 mtx_lock(&pr->pr_mtx); 1464 n->m_next = 1465 ni6_nametodns(pr->pr_host, strlen(pr->pr_host), oldfqdn); 1466 mtx_unlock(&pr->pr_mtx); 1467 if (n->m_next == NULL) 1468 goto bad; 1469 /* XXX we assume that n->m_next is not a chain */ 1470 if (n->m_next->m_next != NULL) 1471 goto bad; 1472 n->m_pkthdr.len += n->m_next->m_len; 1473 break; 1474 case NI_QTYPE_NODEADDR: 1475 { 1476 int lenlim, copied; 1477 1478 nni6->ni_code = ICMP6_NI_SUCCESS; 1479 n->m_pkthdr.len = n->m_len = 1480 sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo); 1481 lenlim = M_TRAILINGSPACE(n); 1482 copied = ni6_store_addrs(ni6, nni6, ifp, lenlim); 1483 /* XXX: reset mbuf length */ 1484 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) + 1485 sizeof(struct icmp6_nodeinfo) + copied; 1486 break; 1487 } 1488 default: 1489 break; /* XXX impossible! */ 1490 } 1491 1492 nni6->ni_type = ICMP6_NI_REPLY; 1493 m_freem(m); 1494 return (n); 1495 1496 bad: 1497 m_freem(m); 1498 if (n) 1499 m_freem(n); 1500 return (NULL); 1501} 1502 1503/* 1504 * make a mbuf with DNS-encoded string. no compression support. 1505 * 1506 * XXX names with less than 2 dots (like "foo" or "foo.section") will be 1507 * treated as truncated name (two \0 at the end). this is a wild guess. 1508 * 1509 * old - return pascal string if non-zero 1510 */ 1511static struct mbuf * 1512ni6_nametodns(const char *name, int namelen, int old) 1513{ 1514 struct mbuf *m; 1515 char *cp, *ep; 1516 const char *p, *q; 1517 int i, len, nterm; 1518 1519 if (old) 1520 len = namelen + 1; 1521 else 1522 len = MCLBYTES; 1523 1524 /* because MAXHOSTNAMELEN is usually 256, we use cluster mbuf */ 1525 MGET(m, M_DONTWAIT, MT_DATA); 1526 if (m && len > MLEN) { 1527 MCLGET(m, M_DONTWAIT); 1528 if ((m->m_flags & M_EXT) == 0) 1529 goto fail; 1530 } 1531 if (!m) 1532 goto fail; 1533 m->m_next = NULL; 1534 1535 if (old) { 1536 m->m_len = len; 1537 *mtod(m, char *) = namelen; 1538 bcopy(name, mtod(m, char *) + 1, namelen); 1539 return m; 1540 } else { 1541 m->m_len = 0; 1542 cp = mtod(m, char *); 1543 ep = mtod(m, char *) + M_TRAILINGSPACE(m); 1544 1545 /* if not certain about my name, return empty buffer */ 1546 if (namelen == 0) 1547 return m; 1548 1549 /* 1550 * guess if it looks like shortened hostname, or FQDN. 1551 * shortened hostname needs two trailing "\0". 1552 */ 1553 i = 0; 1554 for (p = name; p < name + namelen; p++) { 1555 if (*p && *p == '.') 1556 i++; 1557 } 1558 if (i < 2) 1559 nterm = 2; 1560 else 1561 nterm = 1; 1562 1563 p = name; 1564 while (cp < ep && p < name + namelen) { 1565 i = 0; 1566 for (q = p; q < name + namelen && *q && *q != '.'; q++) 1567 i++; 1568 /* result does not fit into mbuf */ 1569 if (cp + i + 1 >= ep) 1570 goto fail; 1571 /* 1572 * DNS label length restriction, RFC1035 page 8. 1573 * "i == 0" case is included here to avoid returning 1574 * 0-length label on "foo..bar". 1575 */ 1576 if (i <= 0 || i >= 64) 1577 goto fail; 1578 *cp++ = i; 1579 bcopy(p, cp, i); 1580 cp += i; 1581 p = q; 1582 if (p < name + namelen && *p == '.') 1583 p++; 1584 } 1585 /* termination */ 1586 if (cp + nterm >= ep) 1587 goto fail; 1588 while (nterm-- > 0) 1589 *cp++ = '\0'; 1590 m->m_len = cp - mtod(m, char *); 1591 return m; 1592 } 1593 1594 panic("should not reach here"); 1595 /* NOTREACHED */ 1596 1597 fail: 1598 if (m) 1599 m_freem(m); 1600 return NULL; 1601} 1602 1603/* 1604 * check if two DNS-encoded string matches. takes care of truncated 1605 * form (with \0\0 at the end). no compression support. 1606 * XXX upper/lowercase match (see RFC2065) 1607 */ 1608static int 1609ni6_dnsmatch(const char *a, int alen, const char *b, int blen) 1610{ 1611 const char *a0, *b0; 1612 int l; 1613 1614 /* simplest case - need validation? */ 1615 if (alen == blen && bcmp(a, b, alen) == 0) 1616 return 1; 1617 1618 a0 = a; 1619 b0 = b; 1620 1621 /* termination is mandatory */ 1622 if (alen < 2 || blen < 2) 1623 return 0; 1624 if (a0[alen - 1] != '\0' || b0[blen - 1] != '\0') 1625 return 0; 1626 alen--; 1627 blen--; 1628 1629 while (a - a0 < alen && b - b0 < blen) { 1630 if (a - a0 + 1 > alen || b - b0 + 1 > blen) 1631 return 0; 1632 1633 if ((signed char)a[0] < 0 || (signed char)b[0] < 0) 1634 return 0; 1635 /* we don't support compression yet */ 1636 if (a[0] >= 64 || b[0] >= 64) 1637 return 0; 1638 1639 /* truncated case */ 1640 if (a[0] == 0 && a - a0 == alen - 1) 1641 return 1; 1642 if (b[0] == 0 && b - b0 == blen - 1) 1643 return 1; 1644 if (a[0] == 0 || b[0] == 0) 1645 return 0; 1646 1647 if (a[0] != b[0]) 1648 return 0; 1649 l = a[0]; 1650 if (a - a0 + 1 + l > alen || b - b0 + 1 + l > blen) 1651 return 0; 1652 if (bcmp(a + 1, b + 1, l) != 0) 1653 return 0; 1654 1655 a += 1 + l; 1656 b += 1 + l; 1657 } 1658 1659 if (a - a0 == alen && b - b0 == blen) 1660 return 1; 1661 else 1662 return 0; 1663} 1664 1665/* 1666 * calculate the number of addresses to be returned in the node info reply. 1667 */ 1668static int 1669ni6_addrs(struct icmp6_nodeinfo *ni6, struct mbuf *m, struct ifnet **ifpp, 1670 struct in6_addr *subj) 1671{ 1672 INIT_VNET_NET(curvnet); 1673 INIT_VNET_INET6(curvnet); 1674 struct ifnet *ifp; 1675 struct in6_ifaddr *ifa6; 1676 struct ifaddr *ifa; 1677 int addrs = 0, addrsofif, iffound = 0; 1678 int niflags = ni6->ni_flags; 1679 1680 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0) { 1681 switch (ni6->ni_code) { 1682 case ICMP6_NI_SUBJ_IPV6: 1683 if (subj == NULL) /* must be impossible... */ 1684 return (0); 1685 break; 1686 default: 1687 /* 1688 * XXX: we only support IPv6 subject address for 1689 * this Qtype. 1690 */ 1691 return (0); 1692 } 1693 } 1694 1695 IFNET_RLOCK(); 1696 for (ifp = TAILQ_FIRST(&V_ifnet); ifp; ifp = TAILQ_NEXT(ifp, if_list)) { 1697 addrsofif = 0; 1698 IF_ADDR_LOCK(ifp); 1699 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 1700 if (ifa->ifa_addr->sa_family != AF_INET6) 1701 continue; 1702 ifa6 = (struct in6_ifaddr *)ifa; 1703 1704 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0 && 1705 IN6_ARE_ADDR_EQUAL(subj, &ifa6->ia_addr.sin6_addr)) 1706 iffound = 1; 1707 1708 /* 1709 * IPv4-mapped addresses can only be returned by a 1710 * Node Information proxy, since they represent 1711 * addresses of IPv4-only nodes, which perforce do 1712 * not implement this protocol. 1713 * [icmp-name-lookups-07, Section 5.4] 1714 * So we don't support NI_NODEADDR_FLAG_COMPAT in 1715 * this function at this moment. 1716 */ 1717 1718 /* What do we have to do about ::1? */ 1719 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1720 case IPV6_ADDR_SCOPE_LINKLOCAL: 1721 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0) 1722 continue; 1723 break; 1724 case IPV6_ADDR_SCOPE_SITELOCAL: 1725 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0) 1726 continue; 1727 break; 1728 case IPV6_ADDR_SCOPE_GLOBAL: 1729 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0) 1730 continue; 1731 break; 1732 default: 1733 continue; 1734 } 1735 1736 /* 1737 * check if anycast is okay. 1738 * XXX: just experimental. not in the spec. 1739 */ 1740 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 && 1741 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0) 1742 continue; /* we need only unicast addresses */ 1743 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 1744 (V_icmp6_nodeinfo & ICMP6_NODEINFO_TMPADDROK) == 0) { 1745 continue; 1746 } 1747 addrsofif++; /* count the address */ 1748 } 1749 IF_ADDR_UNLOCK(ifp); 1750 if (iffound) { 1751 *ifpp = ifp; 1752 IFNET_RUNLOCK(); 1753 return (addrsofif); 1754 } 1755 1756 addrs += addrsofif; 1757 } 1758 IFNET_RUNLOCK(); 1759 1760 return (addrs); 1761} 1762 1763static int 1764ni6_store_addrs(struct icmp6_nodeinfo *ni6, struct icmp6_nodeinfo *nni6, 1765 struct ifnet *ifp0, int resid) 1766{ 1767 INIT_VNET_NET(curvnet); 1768 INIT_VNET_INET6(curvnet); 1769 struct ifnet *ifp = ifp0 ? ifp0 : TAILQ_FIRST(&V_ifnet); 1770 struct in6_ifaddr *ifa6; 1771 struct ifaddr *ifa; 1772 struct ifnet *ifp_dep = NULL; 1773 int copied = 0, allow_deprecated = 0; 1774 u_char *cp = (u_char *)(nni6 + 1); 1775 int niflags = ni6->ni_flags; 1776 u_int32_t ltime; 1777 1778 if (ifp0 == NULL && !(niflags & NI_NODEADDR_FLAG_ALL)) 1779 return (0); /* needless to copy */ 1780 1781 IFNET_RLOCK(); 1782 again: 1783 1784 for (; ifp; ifp = TAILQ_NEXT(ifp, if_list)) { 1785 IF_ADDR_LOCK(ifp); 1786 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 1787 if (ifa->ifa_addr->sa_family != AF_INET6) 1788 continue; 1789 ifa6 = (struct in6_ifaddr *)ifa; 1790 1791 if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) != 0 && 1792 allow_deprecated == 0) { 1793 /* 1794 * prefererred address should be put before 1795 * deprecated addresses. 1796 */ 1797 1798 /* record the interface for later search */ 1799 if (ifp_dep == NULL) 1800 ifp_dep = ifp; 1801 1802 continue; 1803 } else if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) == 0 && 1804 allow_deprecated != 0) 1805 continue; /* we now collect deprecated addrs */ 1806 1807 /* What do we have to do about ::1? */ 1808 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1809 case IPV6_ADDR_SCOPE_LINKLOCAL: 1810 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0) 1811 continue; 1812 break; 1813 case IPV6_ADDR_SCOPE_SITELOCAL: 1814 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0) 1815 continue; 1816 break; 1817 case IPV6_ADDR_SCOPE_GLOBAL: 1818 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0) 1819 continue; 1820 break; 1821 default: 1822 continue; 1823 } 1824 1825 /* 1826 * check if anycast is okay. 1827 * XXX: just experimental. not in the spec. 1828 */ 1829 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 && 1830 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0) 1831 continue; 1832 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 1833 (V_icmp6_nodeinfo & ICMP6_NODEINFO_TMPADDROK) == 0) { 1834 continue; 1835 } 1836 1837 /* now we can copy the address */ 1838 if (resid < sizeof(struct in6_addr) + 1839 sizeof(u_int32_t)) { 1840 IF_ADDR_UNLOCK(ifp); 1841 /* 1842 * We give up much more copy. 1843 * Set the truncate flag and return. 1844 */ 1845 nni6->ni_flags |= NI_NODEADDR_FLAG_TRUNCATE; 1846 IFNET_RUNLOCK(); 1847 return (copied); 1848 } 1849 1850 /* 1851 * Set the TTL of the address. 1852 * The TTL value should be one of the following 1853 * according to the specification: 1854 * 1855 * 1. The remaining lifetime of a DHCP lease on the 1856 * address, or 1857 * 2. The remaining Valid Lifetime of a prefix from 1858 * which the address was derived through Stateless 1859 * Autoconfiguration. 1860 * 1861 * Note that we currently do not support stateful 1862 * address configuration by DHCPv6, so the former 1863 * case can't happen. 1864 */ 1865 if (ifa6->ia6_lifetime.ia6t_expire == 0) 1866 ltime = ND6_INFINITE_LIFETIME; 1867 else { 1868 if (ifa6->ia6_lifetime.ia6t_expire > 1869 time_second) 1870 ltime = htonl(ifa6->ia6_lifetime.ia6t_expire - time_second); 1871 else 1872 ltime = 0; 1873 } 1874 1875 bcopy(<ime, cp, sizeof(u_int32_t)); 1876 cp += sizeof(u_int32_t); 1877 1878 /* copy the address itself */ 1879 bcopy(&ifa6->ia_addr.sin6_addr, cp, 1880 sizeof(struct in6_addr)); 1881 in6_clearscope((struct in6_addr *)cp); /* XXX */ 1882 cp += sizeof(struct in6_addr); 1883 1884 resid -= (sizeof(struct in6_addr) + sizeof(u_int32_t)); 1885 copied += (sizeof(struct in6_addr) + sizeof(u_int32_t)); 1886 } 1887 IF_ADDR_UNLOCK(ifp); 1888 if (ifp0) /* we need search only on the specified IF */ 1889 break; 1890 } 1891 1892 if (allow_deprecated == 0 && ifp_dep != NULL) { 1893 ifp = ifp_dep; 1894 allow_deprecated = 1; 1895 1896 goto again; 1897 } 1898 1899 IFNET_RUNLOCK(); 1900 1901 return (copied); 1902} 1903 1904/* 1905 * XXX almost dup'ed code with rip6_input. 1906 */ 1907static int 1908icmp6_rip6_input(struct mbuf **mp, int off) 1909{ 1910 INIT_VNET_INET(curvnet); 1911 INIT_VNET_INET6(curvnet); 1912 struct mbuf *m = *mp; 1913 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1914 struct inpcb *in6p; 1915 struct inpcb *last = NULL; 1916 struct sockaddr_in6 fromsa; 1917 struct icmp6_hdr *icmp6; 1918 struct mbuf *opts = NULL; 1919 1920#ifndef PULLDOWN_TEST 1921 /* this is assumed to be safe. */ 1922 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off); 1923#else 1924 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 1925 if (icmp6 == NULL) { 1926 /* m is already reclaimed */ 1927 return (IPPROTO_DONE); 1928 } 1929#endif 1930 1931 /* 1932 * XXX: the address may have embedded scope zone ID, which should be 1933 * hidden from applications. 1934 */ 1935 bzero(&fromsa, sizeof(fromsa)); 1936 fromsa.sin6_family = AF_INET6; 1937 fromsa.sin6_len = sizeof(struct sockaddr_in6); 1938 fromsa.sin6_addr = ip6->ip6_src; 1939 if (sa6_recoverscope(&fromsa)) { 1940 m_freem(m); 1941 return (IPPROTO_DONE); 1942 } 1943 1944 INP_INFO_RLOCK(&V_ripcbinfo); 1945 LIST_FOREACH(in6p, &V_ripcb, inp_list) { 1946 if ((in6p->inp_vflag & INP_IPV6) == 0) 1947 continue; 1948 if (in6p->inp_ip_p != IPPROTO_ICMPV6) 1949 continue; 1950 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr) && 1951 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr, &ip6->ip6_dst)) 1952 continue; 1953 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr) && 1954 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr, &ip6->ip6_src)) 1955 continue; 1956 INP_RLOCK(in6p); 1957 if (ICMP6_FILTER_WILLBLOCK(icmp6->icmp6_type, 1958 in6p->in6p_icmp6filt)) { 1959 INP_RUNLOCK(in6p); 1960 continue; 1961 } 1962 if (last != NULL) { 1963 struct mbuf *n = NULL; 1964 1965 /* 1966 * Recent network drivers tend to allocate a single 1967 * mbuf cluster, rather than to make a couple of 1968 * mbufs without clusters. Also, since the IPv6 code 1969 * path tries to avoid m_pullup(), it is highly 1970 * probable that we still have an mbuf cluster here 1971 * even though the necessary length can be stored in an 1972 * mbuf's internal buffer. 1973 * Meanwhile, the default size of the receive socket 1974 * buffer for raw sockets is not so large. This means 1975 * the possibility of packet loss is relatively higher 1976 * than before. To avoid this scenario, we copy the 1977 * received data to a separate mbuf that does not use 1978 * a cluster, if possible. 1979 * XXX: it is better to copy the data after stripping 1980 * intermediate headers. 1981 */ 1982 if ((m->m_flags & M_EXT) && m->m_next == NULL && 1983 m->m_len <= MHLEN) { 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, 1988 m->m_len); 1989 n->m_len = m->m_len; 1990 } else { 1991 m_free(n); 1992 n = NULL; 1993 } 1994 } 1995 } 1996 if (n != NULL || 1997 (n = m_copy(m, 0, (int)M_COPYALL)) != NULL) { 1998 if (last->inp_flags & INP_CONTROLOPTS) 1999 ip6_savecontrol(last, n, &opts); 2000 /* strip intermediate headers */ 2001 m_adj(n, off); 2002 SOCKBUF_LOCK(&last->inp_socket->so_rcv); 2003 if (sbappendaddr_locked( 2004 &last->inp_socket->so_rcv, 2005 (struct sockaddr *)&fromsa, n, opts) 2006 == 0) { 2007 /* should notify about lost packet */ 2008 m_freem(n); 2009 if (opts) { 2010 m_freem(opts); 2011 } 2012 SOCKBUF_UNLOCK( 2013 &last->inp_socket->so_rcv); 2014 } else 2015 sorwakeup_locked(last->inp_socket); 2016 opts = NULL; 2017 } 2018 INP_RUNLOCK(last); 2019 } 2020 last = in6p; 2021 } 2022 INP_INFO_RUNLOCK(&V_ripcbinfo); 2023 if (last != NULL) { 2024 if (last->inp_flags & INP_CONTROLOPTS) 2025 ip6_savecontrol(last, m, &opts); 2026 /* strip intermediate headers */ 2027 m_adj(m, off); 2028 2029 /* avoid using mbuf clusters if possible (see above) */ 2030 if ((m->m_flags & M_EXT) && m->m_next == NULL && 2031 m->m_len <= MHLEN) { 2032 struct mbuf *n; 2033 2034 MGET(n, M_DONTWAIT, m->m_type); 2035 if (n != NULL) { 2036 if (m_dup_pkthdr(n, m, M_NOWAIT)) { 2037 bcopy(m->m_data, n->m_data, m->m_len); 2038 n->m_len = m->m_len; 2039 2040 m_freem(m); 2041 m = n; 2042 } else { 2043 m_freem(n); 2044 n = NULL; 2045 } 2046 } 2047 } 2048 SOCKBUF_LOCK(&last->inp_socket->so_rcv); 2049 if (sbappendaddr_locked(&last->inp_socket->so_rcv, 2050 (struct sockaddr *)&fromsa, m, opts) == 0) { 2051 m_freem(m); 2052 if (opts) 2053 m_freem(opts); 2054 SOCKBUF_UNLOCK(&last->inp_socket->so_rcv); 2055 } else 2056 sorwakeup_locked(last->inp_socket); 2057 INP_RUNLOCK(last); 2058 } else { 2059 m_freem(m); 2060 IP6STAT_DEC(ip6s_delivered); 2061 } 2062 return IPPROTO_DONE; 2063} 2064 2065/* 2066 * Reflect the ip6 packet back to the source. 2067 * OFF points to the icmp6 header, counted from the top of the mbuf. 2068 */ 2069void 2070icmp6_reflect(struct mbuf *m, size_t off) 2071{ 2072 INIT_VNET_INET6(curvnet); 2073 struct ip6_hdr *ip6; 2074 struct icmp6_hdr *icmp6; 2075 struct in6_ifaddr *ia; 2076 int plen; 2077 int type, code; 2078 struct ifnet *outif = NULL; 2079 struct in6_addr origdst, *src = NULL; 2080 2081 /* too short to reflect */ 2082 if (off < sizeof(struct ip6_hdr)) { 2083 nd6log((LOG_DEBUG, 2084 "sanity fail: off=%lx, sizeof(ip6)=%lx in %s:%d\n", 2085 (u_long)off, (u_long)sizeof(struct ip6_hdr), 2086 __FILE__, __LINE__)); 2087 goto bad; 2088 } 2089 2090 /* 2091 * If there are extra headers between IPv6 and ICMPv6, strip 2092 * off that header first. 2093 */ 2094#ifdef DIAGNOSTIC 2095 if (sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) > MHLEN) 2096 panic("assumption failed in icmp6_reflect"); 2097#endif 2098 if (off > sizeof(struct ip6_hdr)) { 2099 size_t l; 2100 struct ip6_hdr nip6; 2101 2102 l = off - sizeof(struct ip6_hdr); 2103 m_copydata(m, 0, sizeof(nip6), (caddr_t)&nip6); 2104 m_adj(m, l); 2105 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 2106 if (m->m_len < l) { 2107 if ((m = m_pullup(m, l)) == NULL) 2108 return; 2109 } 2110 bcopy((caddr_t)&nip6, mtod(m, caddr_t), sizeof(nip6)); 2111 } else /* off == sizeof(struct ip6_hdr) */ { 2112 size_t l; 2113 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 2114 if (m->m_len < l) { 2115 if ((m = m_pullup(m, l)) == NULL) 2116 return; 2117 } 2118 } 2119 plen = m->m_pkthdr.len - sizeof(struct ip6_hdr); 2120 ip6 = mtod(m, struct ip6_hdr *); 2121 ip6->ip6_nxt = IPPROTO_ICMPV6; 2122 icmp6 = (struct icmp6_hdr *)(ip6 + 1); 2123 type = icmp6->icmp6_type; /* keep type for statistics */ 2124 code = icmp6->icmp6_code; /* ditto. */ 2125 2126 origdst = ip6->ip6_dst; 2127 /* 2128 * ip6_input() drops a packet if its src is multicast. 2129 * So, the src is never multicast. 2130 */ 2131 ip6->ip6_dst = ip6->ip6_src; 2132 2133 /* 2134 * If the incoming packet was addressed directly to us (i.e. unicast), 2135 * use dst as the src for the reply. 2136 * The IN6_IFF_NOTREADY case should be VERY rare, but is possible 2137 * (for example) when we encounter an error while forwarding procedure 2138 * destined to a duplicated address of ours. 2139 * Note that ip6_getdstifaddr() may fail if we are in an error handling 2140 * procedure of an outgoing packet of our own, in which case we need 2141 * to search in the ifaddr list. 2142 */ 2143 if (!IN6_IS_ADDR_MULTICAST(&origdst)) { 2144 if ((ia = ip6_getdstifaddr(m))) { 2145 if (!(ia->ia6_flags & 2146 (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY))) 2147 src = &ia->ia_addr.sin6_addr; 2148 } else { 2149 struct sockaddr_in6 d; 2150 2151 bzero(&d, sizeof(d)); 2152 d.sin6_family = AF_INET6; 2153 d.sin6_len = sizeof(d); 2154 d.sin6_addr = origdst; 2155 ia = (struct in6_ifaddr *) 2156 ifa_ifwithaddr((struct sockaddr *)&d); 2157 if (ia && 2158 !(ia->ia6_flags & 2159 (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY))) { 2160 src = &ia->ia_addr.sin6_addr; 2161 } 2162 } 2163 } 2164 2165 if (src == NULL) { 2166 int e; 2167 struct sockaddr_in6 sin6; 2168 struct route_in6 ro; 2169 2170 /* 2171 * This case matches to multicasts, our anycast, or unicasts 2172 * that we do not own. Select a source address based on the 2173 * source address of the erroneous packet. 2174 */ 2175 bzero(&sin6, sizeof(sin6)); 2176 sin6.sin6_family = AF_INET6; 2177 sin6.sin6_len = sizeof(sin6); 2178 sin6.sin6_addr = ip6->ip6_dst; /* zone ID should be embedded */ 2179 2180 bzero(&ro, sizeof(ro)); 2181 src = in6_selectsrc(&sin6, NULL, NULL, &ro, NULL, &outif, &e); 2182 if (ro.ro_rt) 2183 RTFREE(ro.ro_rt); /* XXX: we could use this */ 2184 if (src == NULL) { 2185 char ip6buf[INET6_ADDRSTRLEN]; 2186 nd6log((LOG_DEBUG, 2187 "icmp6_reflect: source can't be determined: " 2188 "dst=%s, error=%d\n", 2189 ip6_sprintf(ip6buf, &sin6.sin6_addr), e)); 2190 goto bad; 2191 } 2192 } 2193 2194 ip6->ip6_src = *src; 2195 ip6->ip6_flow = 0; 2196 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2197 ip6->ip6_vfc |= IPV6_VERSION; 2198 ip6->ip6_nxt = IPPROTO_ICMPV6; 2199 if (outif) 2200 ip6->ip6_hlim = ND_IFINFO(outif)->chlim; 2201 else if (m->m_pkthdr.rcvif) { 2202 /* XXX: This may not be the outgoing interface */ 2203 ip6->ip6_hlim = ND_IFINFO(m->m_pkthdr.rcvif)->chlim; 2204 } else 2205 ip6->ip6_hlim = V_ip6_defhlim; 2206 2207 icmp6->icmp6_cksum = 0; 2208 icmp6->icmp6_cksum = in6_cksum(m, IPPROTO_ICMPV6, 2209 sizeof(struct ip6_hdr), plen); 2210 2211 /* 2212 * XXX option handling 2213 */ 2214 2215 m->m_flags &= ~(M_BCAST|M_MCAST); 2216 2217 ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL); 2218 if (outif) 2219 icmp6_ifoutstat_inc(outif, type, code); 2220 2221 return; 2222 2223 bad: 2224 m_freem(m); 2225 return; 2226} 2227 2228void 2229icmp6_fasttimo(void) 2230{ 2231 2232 mld_fasttimo(); 2233} 2234 2235void 2236icmp6_slowtimo(void) 2237{ 2238 2239 mld_slowtimo(); 2240} 2241 2242static const char * 2243icmp6_redirect_diag(struct in6_addr *src6, struct in6_addr *dst6, 2244 struct in6_addr *tgt6) 2245{ 2246 static char buf[1024]; 2247 char ip6bufs[INET6_ADDRSTRLEN]; 2248 char ip6bufd[INET6_ADDRSTRLEN]; 2249 char ip6buft[INET6_ADDRSTRLEN]; 2250 snprintf(buf, sizeof(buf), "(src=%s dst=%s tgt=%s)", 2251 ip6_sprintf(ip6bufs, src6), ip6_sprintf(ip6bufd, dst6), 2252 ip6_sprintf(ip6buft, tgt6)); 2253 return buf; 2254} 2255 2256void 2257icmp6_redirect_input(struct mbuf *m, int off) 2258{ 2259 INIT_VNET_INET6(curvnet); 2260 struct ifnet *ifp; 2261 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 2262 struct nd_redirect *nd_rd; 2263 int icmp6len = ntohs(ip6->ip6_plen); 2264 char *lladdr = NULL; 2265 int lladdrlen = 0; 2266 u_char *redirhdr = NULL; 2267 int redirhdrlen = 0; 2268 struct rtentry *rt = NULL; 2269 int is_router; 2270 int is_onlink; 2271 struct in6_addr src6 = ip6->ip6_src; 2272 struct in6_addr redtgt6; 2273 struct in6_addr reddst6; 2274 union nd_opts ndopts; 2275 char ip6buf[INET6_ADDRSTRLEN]; 2276 2277 if (!m) 2278 return; 2279 2280 ifp = m->m_pkthdr.rcvif; 2281 2282 if (!ifp) 2283 return; 2284 2285 /* XXX if we are router, we don't update route by icmp6 redirect */ 2286 if (V_ip6_forwarding) 2287 goto freeit; 2288 if (!V_icmp6_rediraccept) 2289 goto freeit; 2290 2291#ifndef PULLDOWN_TEST 2292 IP6_EXTHDR_CHECK(m, off, icmp6len,); 2293 nd_rd = (struct nd_redirect *)((caddr_t)ip6 + off); 2294#else 2295 IP6_EXTHDR_GET(nd_rd, struct nd_redirect *, m, off, icmp6len); 2296 if (nd_rd == NULL) { 2297 ICMP6STAT_INC(icp6s_tooshort); 2298 return; 2299 } 2300#endif 2301 redtgt6 = nd_rd->nd_rd_target; 2302 reddst6 = nd_rd->nd_rd_dst; 2303 2304 if (in6_setscope(&redtgt6, m->m_pkthdr.rcvif, NULL) || 2305 in6_setscope(&reddst6, m->m_pkthdr.rcvif, NULL)) { 2306 goto freeit; 2307 } 2308 2309 /* validation */ 2310 if (!IN6_IS_ADDR_LINKLOCAL(&src6)) { 2311 nd6log((LOG_ERR, 2312 "ICMP6 redirect sent from %s rejected; " 2313 "must be from linklocal\n", 2314 ip6_sprintf(ip6buf, &src6))); 2315 goto bad; 2316 } 2317 if (ip6->ip6_hlim != 255) { 2318 nd6log((LOG_ERR, 2319 "ICMP6 redirect sent from %s rejected; " 2320 "hlim=%d (must be 255)\n", 2321 ip6_sprintf(ip6buf, &src6), ip6->ip6_hlim)); 2322 goto bad; 2323 } 2324 { 2325 /* ip6->ip6_src must be equal to gw for icmp6->icmp6_reddst */ 2326 struct sockaddr_in6 sin6; 2327 struct in6_addr *gw6; 2328 2329 bzero(&sin6, sizeof(sin6)); 2330 sin6.sin6_family = AF_INET6; 2331 sin6.sin6_len = sizeof(struct sockaddr_in6); 2332 bcopy(&reddst6, &sin6.sin6_addr, sizeof(reddst6)); 2333 rt = rtalloc1((struct sockaddr *)&sin6, 0, 0UL); 2334 if (rt) { 2335 if (rt->rt_gateway == NULL || 2336 rt->rt_gateway->sa_family != AF_INET6) { 2337 nd6log((LOG_ERR, 2338 "ICMP6 redirect rejected; no route " 2339 "with inet6 gateway found for redirect dst: %s\n", 2340 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2341 RTFREE_LOCKED(rt); 2342 goto bad; 2343 } 2344 2345 gw6 = &(((struct sockaddr_in6 *)rt->rt_gateway)->sin6_addr); 2346 if (bcmp(&src6, gw6, sizeof(struct in6_addr)) != 0) { 2347 nd6log((LOG_ERR, 2348 "ICMP6 redirect rejected; " 2349 "not equal to gw-for-src=%s (must be same): " 2350 "%s\n", 2351 ip6_sprintf(ip6buf, gw6), 2352 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2353 RTFREE_LOCKED(rt); 2354 goto bad; 2355 } 2356 } else { 2357 nd6log((LOG_ERR, 2358 "ICMP6 redirect rejected; " 2359 "no route found for redirect dst: %s\n", 2360 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2361 goto bad; 2362 } 2363 RTFREE_LOCKED(rt); 2364 rt = NULL; 2365 } 2366 if (IN6_IS_ADDR_MULTICAST(&reddst6)) { 2367 nd6log((LOG_ERR, 2368 "ICMP6 redirect rejected; " 2369 "redirect dst must be unicast: %s\n", 2370 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2371 goto bad; 2372 } 2373 2374 is_router = is_onlink = 0; 2375 if (IN6_IS_ADDR_LINKLOCAL(&redtgt6)) 2376 is_router = 1; /* router case */ 2377 if (bcmp(&redtgt6, &reddst6, sizeof(redtgt6)) == 0) 2378 is_onlink = 1; /* on-link destination case */ 2379 if (!is_router && !is_onlink) { 2380 nd6log((LOG_ERR, 2381 "ICMP6 redirect rejected; " 2382 "neither router case nor onlink case: %s\n", 2383 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2384 goto bad; 2385 } 2386 /* validation passed */ 2387 2388 icmp6len -= sizeof(*nd_rd); 2389 nd6_option_init(nd_rd + 1, icmp6len, &ndopts); 2390 if (nd6_options(&ndopts) < 0) { 2391 nd6log((LOG_INFO, "icmp6_redirect_input: " 2392 "invalid ND option, rejected: %s\n", 2393 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2394 /* nd6_options have incremented stats */ 2395 goto freeit; 2396 } 2397 2398 if (ndopts.nd_opts_tgt_lladdr) { 2399 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 2400 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 2401 } 2402 2403 if (ndopts.nd_opts_rh) { 2404 redirhdrlen = ndopts.nd_opts_rh->nd_opt_rh_len; 2405 redirhdr = (u_char *)(ndopts.nd_opts_rh + 1); /* xxx */ 2406 } 2407 2408 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 2409 nd6log((LOG_INFO, 2410 "icmp6_redirect_input: lladdrlen mismatch for %s " 2411 "(if %d, icmp6 packet %d): %s\n", 2412 ip6_sprintf(ip6buf, &redtgt6), 2413 ifp->if_addrlen, lladdrlen - 2, 2414 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2415 goto bad; 2416 } 2417 2418 /* RFC 2461 8.3 */ 2419 nd6_cache_lladdr(ifp, &redtgt6, lladdr, lladdrlen, ND_REDIRECT, 2420 is_onlink ? ND_REDIRECT_ONLINK : ND_REDIRECT_ROUTER); 2421 2422 if (!is_onlink) { /* better router case. perform rtredirect. */ 2423 /* perform rtredirect */ 2424 struct sockaddr_in6 sdst; 2425 struct sockaddr_in6 sgw; 2426 struct sockaddr_in6 ssrc; 2427 2428 bzero(&sdst, sizeof(sdst)); 2429 bzero(&sgw, sizeof(sgw)); 2430 bzero(&ssrc, sizeof(ssrc)); 2431 sdst.sin6_family = sgw.sin6_family = ssrc.sin6_family = AF_INET6; 2432 sdst.sin6_len = sgw.sin6_len = ssrc.sin6_len = 2433 sizeof(struct sockaddr_in6); 2434 bcopy(&redtgt6, &sgw.sin6_addr, sizeof(struct in6_addr)); 2435 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2436 bcopy(&src6, &ssrc.sin6_addr, sizeof(struct in6_addr)); 2437 rtredirect((struct sockaddr *)&sdst, (struct sockaddr *)&sgw, 2438 (struct sockaddr *)NULL, RTF_GATEWAY | RTF_HOST, 2439 (struct sockaddr *)&ssrc); 2440 } 2441 /* finally update cached route in each socket via pfctlinput */ 2442 { 2443 struct sockaddr_in6 sdst; 2444 2445 bzero(&sdst, sizeof(sdst)); 2446 sdst.sin6_family = AF_INET6; 2447 sdst.sin6_len = sizeof(struct sockaddr_in6); 2448 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2449 pfctlinput(PRC_REDIRECT_HOST, (struct sockaddr *)&sdst); 2450#ifdef IPSEC 2451 key_sa_routechange((struct sockaddr *)&sdst); 2452#endif /* IPSEC */ 2453 } 2454 2455 freeit: 2456 m_freem(m); 2457 return; 2458 2459 bad: 2460 ICMP6STAT_INC(icp6s_badredirect); 2461 m_freem(m); 2462} 2463 2464void 2465icmp6_redirect_output(struct mbuf *m0, struct rtentry *rt) 2466{ 2467 INIT_VNET_INET6(curvnet); 2468 struct ifnet *ifp; /* my outgoing interface */ 2469 struct in6_addr *ifp_ll6; 2470 struct in6_addr *router_ll6; 2471 struct ip6_hdr *sip6; /* m0 as struct ip6_hdr */ 2472 struct mbuf *m = NULL; /* newly allocated one */ 2473 struct ip6_hdr *ip6; /* m as struct ip6_hdr */ 2474 struct nd_redirect *nd_rd; 2475 struct llentry *ln = NULL; 2476 size_t maxlen; 2477 u_char *p; 2478 struct ifnet *outif = NULL; 2479 struct sockaddr_in6 src_sa; 2480 2481 icmp6_errcount(&V_icmp6stat.icp6s_outerrhist, ND_REDIRECT, 0); 2482 2483 /* if we are not router, we don't send icmp6 redirect */ 2484 if (!V_ip6_forwarding) 2485 goto fail; 2486 2487 /* sanity check */ 2488 if (!m0 || !rt || !(rt->rt_flags & RTF_UP) || !(ifp = rt->rt_ifp)) 2489 goto fail; 2490 2491 /* 2492 * Address check: 2493 * the source address must identify a neighbor, and 2494 * the destination address must not be a multicast address 2495 * [RFC 2461, sec 8.2] 2496 */ 2497 sip6 = mtod(m0, struct ip6_hdr *); 2498 bzero(&src_sa, sizeof(src_sa)); 2499 src_sa.sin6_family = AF_INET6; 2500 src_sa.sin6_len = sizeof(src_sa); 2501 src_sa.sin6_addr = sip6->ip6_src; 2502 if (nd6_is_addr_neighbor(&src_sa, ifp) == 0) 2503 goto fail; 2504 if (IN6_IS_ADDR_MULTICAST(&sip6->ip6_dst)) 2505 goto fail; /* what should we do here? */ 2506 2507 /* rate limit */ 2508 if (icmp6_ratelimit(&sip6->ip6_src, ND_REDIRECT, 0)) 2509 goto fail; 2510 2511 /* 2512 * Since we are going to append up to 1280 bytes (= IPV6_MMTU), 2513 * we almost always ask for an mbuf cluster for simplicity. 2514 * (MHLEN < IPV6_MMTU is almost always true) 2515 */ 2516#if IPV6_MMTU >= MCLBYTES 2517# error assumption failed about IPV6_MMTU and MCLBYTES 2518#endif 2519 MGETHDR(m, M_DONTWAIT, MT_HEADER); 2520 if (m && IPV6_MMTU >= MHLEN) 2521 MCLGET(m, M_DONTWAIT); 2522 if (!m) 2523 goto fail; 2524 m->m_pkthdr.rcvif = NULL; 2525 m->m_len = 0; 2526 maxlen = M_TRAILINGSPACE(m); 2527 maxlen = min(IPV6_MMTU, maxlen); 2528 /* just for safety */ 2529 if (maxlen < sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) + 2530 ((sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7)) { 2531 goto fail; 2532 } 2533 2534 { 2535 /* get ip6 linklocal address for ifp(my outgoing interface). */ 2536 struct in6_ifaddr *ia; 2537 if ((ia = in6ifa_ifpforlinklocal(ifp, 2538 IN6_IFF_NOTREADY| 2539 IN6_IFF_ANYCAST)) == NULL) 2540 goto fail; 2541 ifp_ll6 = &ia->ia_addr.sin6_addr; 2542 } 2543 2544 /* get ip6 linklocal address for the router. */ 2545 if (rt->rt_gateway && (rt->rt_flags & RTF_GATEWAY)) { 2546 struct sockaddr_in6 *sin6; 2547 sin6 = (struct sockaddr_in6 *)rt->rt_gateway; 2548 router_ll6 = &sin6->sin6_addr; 2549 if (!IN6_IS_ADDR_LINKLOCAL(router_ll6)) 2550 router_ll6 = (struct in6_addr *)NULL; 2551 } else 2552 router_ll6 = (struct in6_addr *)NULL; 2553 2554 /* ip6 */ 2555 ip6 = mtod(m, struct ip6_hdr *); 2556 ip6->ip6_flow = 0; 2557 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2558 ip6->ip6_vfc |= IPV6_VERSION; 2559 /* ip6->ip6_plen will be set later */ 2560 ip6->ip6_nxt = IPPROTO_ICMPV6; 2561 ip6->ip6_hlim = 255; 2562 /* ip6->ip6_src must be linklocal addr for my outgoing if. */ 2563 bcopy(ifp_ll6, &ip6->ip6_src, sizeof(struct in6_addr)); 2564 bcopy(&sip6->ip6_src, &ip6->ip6_dst, sizeof(struct in6_addr)); 2565 2566 /* ND Redirect */ 2567 nd_rd = (struct nd_redirect *)(ip6 + 1); 2568 nd_rd->nd_rd_type = ND_REDIRECT; 2569 nd_rd->nd_rd_code = 0; 2570 nd_rd->nd_rd_reserved = 0; 2571 if (rt->rt_flags & RTF_GATEWAY) { 2572 /* 2573 * nd_rd->nd_rd_target must be a link-local address in 2574 * better router cases. 2575 */ 2576 if (!router_ll6) 2577 goto fail; 2578 bcopy(router_ll6, &nd_rd->nd_rd_target, 2579 sizeof(nd_rd->nd_rd_target)); 2580 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2581 sizeof(nd_rd->nd_rd_dst)); 2582 } else { 2583 /* make sure redtgt == reddst */ 2584 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_target, 2585 sizeof(nd_rd->nd_rd_target)); 2586 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2587 sizeof(nd_rd->nd_rd_dst)); 2588 } 2589 2590 p = (u_char *)(nd_rd + 1); 2591 2592 if (!router_ll6) 2593 goto nolladdropt; 2594 2595 { 2596 /* target lladdr option */ 2597 int len; 2598 struct nd_opt_hdr *nd_opt; 2599 char *lladdr; 2600 2601 IF_AFDATA_LOCK(ifp); 2602 ln = nd6_lookup(router_ll6, 0, ifp); 2603 IF_AFDATA_UNLOCK(ifp); 2604 if (ln == NULL) 2605 goto nolladdropt; 2606 2607 len = sizeof(*nd_opt) + ifp->if_addrlen; 2608 len = (len + 7) & ~7; /* round by 8 */ 2609 /* safety check */ 2610 if (len + (p - (u_char *)ip6) > maxlen) 2611 goto nolladdropt; 2612 2613 if (ln->la_flags & LLE_VALID) { 2614 nd_opt = (struct nd_opt_hdr *)p; 2615 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 2616 nd_opt->nd_opt_len = len >> 3; 2617 lladdr = (char *)(nd_opt + 1); 2618 bcopy(&ln->ll_addr, lladdr, ifp->if_addrlen); 2619 p += len; 2620 } 2621 } 2622nolladdropt: 2623 if (ln != NULL) 2624 LLE_RUNLOCK(ln); 2625 2626 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2627 2628 /* just to be safe */ 2629#ifdef M_DECRYPTED /*not openbsd*/ 2630 if (m0->m_flags & M_DECRYPTED) 2631 goto noredhdropt; 2632#endif 2633 if (p - (u_char *)ip6 > maxlen) 2634 goto noredhdropt; 2635 2636 { 2637 /* redirected header option */ 2638 int len; 2639 struct nd_opt_rd_hdr *nd_opt_rh; 2640 2641 /* 2642 * compute the maximum size for icmp6 redirect header option. 2643 * XXX room for auth header? 2644 */ 2645 len = maxlen - (p - (u_char *)ip6); 2646 len &= ~7; 2647 2648 /* This is just for simplicity. */ 2649 if (m0->m_pkthdr.len != m0->m_len) { 2650 if (m0->m_next) { 2651 m_freem(m0->m_next); 2652 m0->m_next = NULL; 2653 } 2654 m0->m_pkthdr.len = m0->m_len; 2655 } 2656 2657 /* 2658 * Redirected header option spec (RFC2461 4.6.3) talks nothing 2659 * about padding/truncate rule for the original IP packet. 2660 * From the discussion on IPv6imp in Feb 1999, 2661 * the consensus was: 2662 * - "attach as much as possible" is the goal 2663 * - pad if not aligned (original size can be guessed by 2664 * original ip6 header) 2665 * Following code adds the padding if it is simple enough, 2666 * and truncates if not. 2667 */ 2668 if (m0->m_next || m0->m_pkthdr.len != m0->m_len) 2669 panic("assumption failed in %s:%d", __FILE__, 2670 __LINE__); 2671 2672 if (len - sizeof(*nd_opt_rh) < m0->m_pkthdr.len) { 2673 /* not enough room, truncate */ 2674 m0->m_pkthdr.len = m0->m_len = len - 2675 sizeof(*nd_opt_rh); 2676 } else { 2677 /* enough room, pad or truncate */ 2678 size_t extra; 2679 2680 extra = m0->m_pkthdr.len % 8; 2681 if (extra) { 2682 /* pad if easy enough, truncate if not */ 2683 if (8 - extra <= M_TRAILINGSPACE(m0)) { 2684 /* pad */ 2685 m0->m_len += (8 - extra); 2686 m0->m_pkthdr.len += (8 - extra); 2687 } else { 2688 /* truncate */ 2689 m0->m_pkthdr.len -= extra; 2690 m0->m_len -= extra; 2691 } 2692 } 2693 len = m0->m_pkthdr.len + sizeof(*nd_opt_rh); 2694 m0->m_pkthdr.len = m0->m_len = len - 2695 sizeof(*nd_opt_rh); 2696 } 2697 2698 nd_opt_rh = (struct nd_opt_rd_hdr *)p; 2699 bzero(nd_opt_rh, sizeof(*nd_opt_rh)); 2700 nd_opt_rh->nd_opt_rh_type = ND_OPT_REDIRECTED_HEADER; 2701 nd_opt_rh->nd_opt_rh_len = len >> 3; 2702 p += sizeof(*nd_opt_rh); 2703 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2704 2705 /* connect m0 to m */ 2706 m_tag_delete_chain(m0, NULL); 2707 m0->m_flags &= ~M_PKTHDR; 2708 m->m_next = m0; 2709 m->m_pkthdr.len = m->m_len + m0->m_len; 2710 m0 = NULL; 2711 } 2712noredhdropt:; 2713 if (m0) { 2714 m_freem(m0); 2715 m0 = NULL; 2716 } 2717 2718 /* XXX: clear embedded link IDs in the inner header */ 2719 in6_clearscope(&sip6->ip6_src); 2720 in6_clearscope(&sip6->ip6_dst); 2721 in6_clearscope(&nd_rd->nd_rd_target); 2722 in6_clearscope(&nd_rd->nd_rd_dst); 2723 2724 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr)); 2725 2726 nd_rd->nd_rd_cksum = 0; 2727 nd_rd->nd_rd_cksum = in6_cksum(m, IPPROTO_ICMPV6, 2728 sizeof(*ip6), ntohs(ip6->ip6_plen)); 2729 2730 /* send the packet to outside... */ 2731 ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL); 2732 if (outif) { 2733 icmp6_ifstat_inc(outif, ifs6_out_msg); 2734 icmp6_ifstat_inc(outif, ifs6_out_redirect); 2735 } 2736 ICMP6STAT_INC(icp6s_outhist[ND_REDIRECT]); 2737 2738 return; 2739 2740fail: 2741 if (m) 2742 m_freem(m); 2743 if (m0) 2744 m_freem(m0); 2745} 2746 2747/* 2748 * ICMPv6 socket option processing. 2749 */ 2750int 2751icmp6_ctloutput(struct socket *so, struct sockopt *sopt) 2752{ 2753 int error = 0; 2754 int optlen; 2755 struct inpcb *inp = sotoinpcb(so); 2756 int level, op, optname; 2757 2758 if (sopt) { 2759 level = sopt->sopt_level; 2760 op = sopt->sopt_dir; 2761 optname = sopt->sopt_name; 2762 optlen = sopt->sopt_valsize; 2763 } else 2764 level = op = optname = optlen = 0; 2765 2766 if (level != IPPROTO_ICMPV6) { 2767 return EINVAL; 2768 } 2769 2770 switch (op) { 2771 case PRCO_SETOPT: 2772 switch (optname) { 2773 case ICMP6_FILTER: 2774 { 2775 struct icmp6_filter ic6f; 2776 2777 if (optlen != sizeof(ic6f)) { 2778 error = EMSGSIZE; 2779 break; 2780 } 2781 error = sooptcopyin(sopt, &ic6f, optlen, optlen); 2782 if (error == 0) { 2783 INP_WLOCK(inp); 2784 *inp->in6p_icmp6filt = ic6f; 2785 INP_WUNLOCK(inp); 2786 } 2787 break; 2788 } 2789 2790 default: 2791 error = ENOPROTOOPT; 2792 break; 2793 } 2794 break; 2795 2796 case PRCO_GETOPT: 2797 switch (optname) { 2798 case ICMP6_FILTER: 2799 { 2800 struct icmp6_filter ic6f; 2801 2802 INP_RLOCK(inp); 2803 ic6f = *inp->in6p_icmp6filt; 2804 INP_RUNLOCK(inp); 2805 error = sooptcopyout(sopt, &ic6f, sizeof(ic6f)); 2806 break; 2807 } 2808 2809 default: 2810 error = ENOPROTOOPT; 2811 break; 2812 } 2813 break; 2814 } 2815 2816 return (error); 2817} 2818 2819/* 2820 * Perform rate limit check. 2821 * Returns 0 if it is okay to send the icmp6 packet. 2822 * Returns 1 if the router SHOULD NOT send this icmp6 packet due to rate 2823 * limitation. 2824 * 2825 * XXX per-destination/type check necessary? 2826 * 2827 * dst - not used at this moment 2828 * type - not used at this moment 2829 * code - not used at this moment 2830 */ 2831static int 2832icmp6_ratelimit(const struct in6_addr *dst, const int type, 2833 const int code) 2834{ 2835 INIT_VNET_INET6(curvnet); 2836 int ret; 2837 2838 ret = 0; /* okay to send */ 2839 2840 /* PPS limit */ 2841 if (!ppsratecheck(&V_icmp6errppslim_last, &V_icmp6errpps_count, 2842 V_icmp6errppslim)) { 2843 /* The packet is subject to rate limit */ 2844 ret++; 2845 } 2846 2847 return ret; 2848} 2849