1 /*- 2 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of the project nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * $KAME: icmp6.c,v 1.211 2001/04/04 05:56:20 itojun Exp $ 30 */ 31 32 /*- 33 * Copyright (c) 1982, 1986, 1988, 1993 34 * The Regents of the University of California. All rights reserved. 35 * 36 * Redistribution and use in source and binary forms, with or without 37 * modification, are permitted provided that the following conditions 38 * are met: 39 * 1. Redistributions of source code must retain the above copyright 40 * notice, this list of conditions and the following disclaimer. 41 * 2. Redistributions in binary form must reproduce the above copyright 42 * notice, this list of conditions and the following disclaimer in the 43 * documentation and/or other materials provided with the distribution. 44 * 4. Neither the name of the University nor the names of its contributors 45 * may be used to endorse or promote products derived from this software 46 * without specific prior written permission. 47 * 48 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 49 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 50 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 51 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 52 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 53 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 54 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 55 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 56 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 57 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 58 * SUCH DAMAGE. 59 * 60 * @(#)ip_icmp.c 8.2 (Berkeley) 1/4/94 61 */ 62 63 #include <sys/cdefs.h> 64 __FBSDID("$FreeBSD$"); 65 66 #include "opt_inet.h" 67 #include "opt_inet6.h" 68 #include "opt_ipsec.h" 69 70 #include <sys/param.h> 71 #include <sys/domain.h> 72 #include <sys/kernel.h> 73 #include <sys/lock.h> 74 #include <sys/malloc.h> 75 #include <sys/mbuf.h> 76 #include <sys/protosw.h> 77 #include <sys/signalvar.h> 78 #include <sys/socket.h> 79 #include <sys/socketvar.h> 80 #include <sys/sx.h> 81 #include <sys/syslog.h> 82 #include <sys/systm.h> 83 #include <sys/time.h> 84 #include <sys/vimage.h> 85 86 #include <net/if.h> 87 #include <net/if_dl.h> 88 #include <net/if_types.h> 89 #include <net/route.h> 90 91 #include <netinet/in.h> 92 #include <netinet/in_pcb.h> 93 #include <netinet/in_var.h> 94 #include <netinet/ip6.h> 95 #include <netinet/icmp6.h> 96 #include <netinet/tcp_var.h> 97 #include <netinet6/in6_ifattach.h> 98 #include <netinet6/in6_pcb.h> 99 #include <netinet6/ip6protosw.h> 100 #include <netinet6/ip6_var.h> 101 #include <netinet6/scope6_var.h> 102 #include <netinet6/mld6_var.h> 103 #include <netinet6/nd6.h> 104 105 #ifdef IPSEC 106 #include <netipsec/ipsec.h> 107 #include <netipsec/key.h> 108 #endif 109 110 extern struct domain inet6domain; 111 112 #ifdef VIMAGE_GLOBALS 113 extern struct inpcbinfo ripcbinfo; 114 extern struct inpcbhead ripcb; 115 extern int icmp6errppslim; 116 extern int icmp6_nodeinfo; 117 118 struct icmp6stat icmp6stat; 119 static int icmp6errpps_count; 120 static struct timeval icmp6errppslim_last; 121 #endif 122 123 static void icmp6_errcount(struct icmp6errstat *, int, int); 124 static int icmp6_rip6_input(struct mbuf **, int); 125 static int icmp6_ratelimit(const struct in6_addr *, const int, const int); 126 static const char *icmp6_redirect_diag __P((struct in6_addr *, 127 struct in6_addr *, struct in6_addr *)); 128 static struct mbuf *ni6_input(struct mbuf *, int); 129 static struct mbuf *ni6_nametodns(const char *, int, int); 130 static int ni6_dnsmatch(const char *, int, const char *, int); 131 static int ni6_addrs __P((struct icmp6_nodeinfo *, struct mbuf *, 132 struct ifnet **, struct in6_addr *)); 133 static int ni6_store_addrs __P((struct icmp6_nodeinfo *, struct icmp6_nodeinfo *, 134 struct ifnet *, int)); 135 static int icmp6_notify_error(struct mbuf **, int, int, int); 136 137 138 void 139 icmp6_init(void) 140 { 141 INIT_VNET_INET6(curvnet); 142 143 V_icmp6errpps_count = 0; 144 145 mld6_init(); 146 } 147 148 static void 149 icmp6_errcount(struct icmp6errstat *stat, int type, int 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(struct mbuf *m, int type, int code, int param, 210 struct ifnet *ifp) 211 { 212 INIT_VNET_INET6(curvnet); 213 struct ip6_hdr *ip6; 214 215 if (ifp == NULL) 216 return; 217 218 #ifndef PULLDOWN_TEST 219 IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), ); 220 #else 221 if (m->m_len < sizeof(struct ip6_hdr)) { 222 m = m_pullup(m, sizeof(struct ip6_hdr)); 223 if (m == NULL) 224 return; 225 } 226 #endif 227 228 ip6 = mtod(m, struct ip6_hdr *); 229 230 if (in6_setscope(&ip6->ip6_src, ifp, NULL) != 0) 231 return; 232 if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0) 233 return; 234 235 icmp6_error(m, type, code, param); 236 } 237 238 /* 239 * Generate an error packet of type error in response to bad IP6 packet. 240 */ 241 void 242 icmp6_error(struct mbuf *m, int type, int code, int param) 243 { 244 INIT_VNET_INET6(curvnet); 245 struct ip6_hdr *oip6, *nip6; 246 struct icmp6_hdr *icmp6; 247 u_int preplen; 248 int off; 249 int nxt; 250 251 V_icmp6stat.icp6s_error++; 252 253 /* count per-type-code statistics */ 254 icmp6_errcount(&V_icmp6stat.icp6s_outerrhist, type, code); 255 256 #ifdef M_DECRYPTED /*not openbsd*/ 257 if (m->m_flags & M_DECRYPTED) { 258 V_icmp6stat.icp6s_canterror++; 259 goto freeit; 260 } 261 #endif 262 263 #ifndef PULLDOWN_TEST 264 IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), ); 265 #else 266 if (m->m_len < sizeof(struct ip6_hdr)) { 267 m = m_pullup(m, sizeof(struct ip6_hdr)); 268 if (m == NULL) 269 return; 270 } 271 #endif 272 oip6 = mtod(m, struct ip6_hdr *); 273 274 /* 275 * If the destination address of the erroneous packet is a multicast 276 * address, or the packet was sent using link-layer multicast, 277 * we should basically suppress sending an error (RFC 2463, Section 278 * 2.4). 279 * We have two exceptions (the item e.2 in that section): 280 * - the Pakcet Too Big message can be sent for path MTU discovery. 281 * - the Parameter Problem Message that can be allowed an icmp6 error 282 * in the option type field. This check has been done in 283 * ip6_unknown_opt(), so we can just check the type and code. 284 */ 285 if ((m->m_flags & (M_BCAST|M_MCAST) || 286 IN6_IS_ADDR_MULTICAST(&oip6->ip6_dst)) && 287 (type != ICMP6_PACKET_TOO_BIG && 288 (type != ICMP6_PARAM_PROB || 289 code != ICMP6_PARAMPROB_OPTION))) 290 goto freeit; 291 292 /* 293 * RFC 2463, 2.4 (e.5): source address check. 294 * XXX: the case of anycast source? 295 */ 296 if (IN6_IS_ADDR_UNSPECIFIED(&oip6->ip6_src) || 297 IN6_IS_ADDR_MULTICAST(&oip6->ip6_src)) 298 goto freeit; 299 300 /* 301 * If we are about to send ICMPv6 against ICMPv6 error/redirect, 302 * don't do it. 303 */ 304 nxt = -1; 305 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); 306 if (off >= 0 && nxt == IPPROTO_ICMPV6) { 307 struct icmp6_hdr *icp; 308 309 #ifndef PULLDOWN_TEST 310 IP6_EXTHDR_CHECK(m, 0, off + sizeof(struct icmp6_hdr), ); 311 icp = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 312 #else 313 IP6_EXTHDR_GET(icp, struct icmp6_hdr *, m, off, 314 sizeof(*icp)); 315 if (icp == NULL) { 316 V_icmp6stat.icp6s_tooshort++; 317 return; 318 } 319 #endif 320 if (icp->icmp6_type < ICMP6_ECHO_REQUEST || 321 icp->icmp6_type == ND_REDIRECT) { 322 /* 323 * ICMPv6 error 324 * Special case: for redirect (which is 325 * informational) we must not send icmp6 error. 326 */ 327 V_icmp6stat.icp6s_canterror++; 328 goto freeit; 329 } else { 330 /* ICMPv6 informational - send the error */ 331 } 332 } else { 333 /* non-ICMPv6 - send the error */ 334 } 335 336 oip6 = mtod(m, struct ip6_hdr *); /* adjust pointer */ 337 338 /* Finally, do rate limitation check. */ 339 if (icmp6_ratelimit(&oip6->ip6_src, type, code)) { 340 V_icmp6stat.icp6s_toofreq++; 341 goto freeit; 342 } 343 344 /* 345 * OK, ICMP6 can be generated. 346 */ 347 348 if (m->m_pkthdr.len >= ICMPV6_PLD_MAXLEN) 349 m_adj(m, ICMPV6_PLD_MAXLEN - m->m_pkthdr.len); 350 351 preplen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 352 M_PREPEND(m, preplen, M_DONTWAIT); 353 if (m && m->m_len < preplen) 354 m = m_pullup(m, preplen); 355 if (m == NULL) { 356 nd6log((LOG_DEBUG, "ENOBUFS in icmp6_error %d\n", __LINE__)); 357 return; 358 } 359 360 nip6 = mtod(m, struct ip6_hdr *); 361 nip6->ip6_src = oip6->ip6_src; 362 nip6->ip6_dst = oip6->ip6_dst; 363 364 in6_clearscope(&oip6->ip6_src); 365 in6_clearscope(&oip6->ip6_dst); 366 367 icmp6 = (struct icmp6_hdr *)(nip6 + 1); 368 icmp6->icmp6_type = type; 369 icmp6->icmp6_code = code; 370 icmp6->icmp6_pptr = htonl((u_int32_t)param); 371 372 /* 373 * icmp6_reflect() is designed to be in the input path. 374 * icmp6_error() can be called from both input and output path, 375 * and if we are in output path rcvif could contain bogus value. 376 * clear m->m_pkthdr.rcvif for safety, we should have enough scope 377 * information in ip header (nip6). 378 */ 379 m->m_pkthdr.rcvif = NULL; 380 381 V_icmp6stat.icp6s_outhist[type]++; 382 icmp6_reflect(m, sizeof(struct ip6_hdr)); /* header order: IPv6 - ICMPv6 */ 383 384 return; 385 386 freeit: 387 /* 388 * If we can't tell whether or not we can generate ICMP6, free it. 389 */ 390 m_freem(m); 391 } 392 393 /* 394 * Process a received ICMP6 message. 395 */ 396 int 397 icmp6_input(struct mbuf **mp, int *offp, int proto) 398 { 399 INIT_VNET_INET6(curvnet); 400 INIT_VPROCG(TD_TO_VPROCG(curthread)); /* XXX V_hostname needs this */ 401 struct mbuf *m = *mp, *n; 402 struct ip6_hdr *ip6, *nip6; 403 struct icmp6_hdr *icmp6, *nicmp6; 404 int off = *offp; 405 int icmp6len = m->m_pkthdr.len - *offp; 406 int code, sum, noff; 407 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 408 409 #ifndef PULLDOWN_TEST 410 IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_hdr), IPPROTO_DONE); 411 /* m might change if M_LOOP. So, call mtod after this */ 412 #endif 413 414 /* 415 * Locate icmp6 structure in mbuf, and check 416 * that not corrupted and of at least minimum length 417 */ 418 419 ip6 = mtod(m, struct ip6_hdr *); 420 if (icmp6len < sizeof(struct icmp6_hdr)) { 421 V_icmp6stat.icp6s_tooshort++; 422 goto freeit; 423 } 424 425 /* 426 * calculate the checksum 427 */ 428 #ifndef PULLDOWN_TEST 429 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off); 430 #else 431 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 432 if (icmp6 == NULL) { 433 V_icmp6stat.icp6s_tooshort++; 434 return IPPROTO_DONE; 435 } 436 #endif 437 code = icmp6->icmp6_code; 438 439 if ((sum = in6_cksum(m, IPPROTO_ICMPV6, off, icmp6len)) != 0) { 440 nd6log((LOG_ERR, 441 "ICMP6 checksum error(%d|%x) %s\n", 442 icmp6->icmp6_type, sum, 443 ip6_sprintf(ip6bufs, &ip6->ip6_src))); 444 V_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 V_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 IP6_EXTHDR_GET(nicmp6, struct icmp6_hdr *, n, off, 592 sizeof(*nicmp6)); 593 noff = off; 594 } 595 nicmp6->icmp6_type = ICMP6_ECHO_REPLY; 596 nicmp6->icmp6_code = 0; 597 if (n) { 598 V_icmp6stat.icp6s_reflect++; 599 V_icmp6stat.icp6s_outhist[ICMP6_ECHO_REPLY]++; 600 icmp6_reflect(n, noff); 601 } 602 break; 603 604 case ICMP6_ECHO_REPLY: 605 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echoreply); 606 if (code != 0) 607 goto badcode; 608 break; 609 610 case MLD_LISTENER_QUERY: 611 case MLD_LISTENER_REPORT: 612 if (icmp6len < sizeof(struct mld_hdr)) 613 goto badlen; 614 if (icmp6->icmp6_type == MLD_LISTENER_QUERY) /* XXX: ugly... */ 615 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldquery); 616 else 617 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldreport); 618 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 619 /* give up local */ 620 mld6_input(m, off); 621 m = NULL; 622 goto freeit; 623 } 624 mld6_input(n, off); 625 /* m stays. */ 626 break; 627 628 case MLD_LISTENER_DONE: 629 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mlddone); 630 if (icmp6len < sizeof(struct mld_hdr)) /* necessary? */ 631 goto badlen; 632 break; /* nothing to be done in kernel */ 633 634 case MLD_MTRACE_RESP: 635 case MLD_MTRACE: 636 /* XXX: these two are experimental. not officially defined. */ 637 /* XXX: per-interface statistics? */ 638 break; /* just pass it to applications */ 639 640 case ICMP6_WRUREQUEST: /* ICMP6_FQDN_QUERY */ 641 { 642 enum { WRU, FQDN } mode; 643 644 if (!V_icmp6_nodeinfo) 645 break; 646 647 if (icmp6len == sizeof(struct icmp6_hdr) + 4) 648 mode = WRU; 649 else if (icmp6len >= sizeof(struct icmp6_nodeinfo)) 650 mode = FQDN; 651 else 652 goto badlen; 653 654 #define hostnamelen strlen(V_hostname) 655 if (mode == FQDN) { 656 #ifndef PULLDOWN_TEST 657 IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_nodeinfo), 658 IPPROTO_DONE); 659 #endif 660 n = m_copy(m, 0, M_COPYALL); 661 if (n) 662 n = ni6_input(n, off); 663 /* XXX meaningless if n == NULL */ 664 noff = sizeof(struct ip6_hdr); 665 } else { 666 u_char *p; 667 int maxlen, maxhlen; 668 669 /* 670 * XXX: this combination of flags is pointless, 671 * but should we keep this for compatibility? 672 */ 673 if ((V_icmp6_nodeinfo & 5) != 5) 674 break; 675 676 if (code != 0) 677 goto badcode; 678 maxlen = sizeof(*nip6) + sizeof(*nicmp6) + 4; 679 if (maxlen >= MCLBYTES) { 680 /* Give up remote */ 681 break; 682 } 683 MGETHDR(n, M_DONTWAIT, m->m_type); 684 if (n && maxlen > MHLEN) { 685 MCLGET(n, M_DONTWAIT); 686 if ((n->m_flags & M_EXT) == 0) { 687 m_free(n); 688 n = NULL; 689 } 690 } 691 if (n && !m_dup_pkthdr(n, m, M_DONTWAIT)) { 692 /* 693 * Previous code did a blind M_COPY_PKTHDR 694 * and said "just for rcvif". If true, then 695 * we could tolerate the dup failing (due to 696 * the deep copy of the tag chain). For now 697 * be conservative and just fail. 698 */ 699 m_free(n); 700 n = NULL; 701 } 702 if (n == NULL) { 703 /* Give up remote */ 704 break; 705 } 706 n->m_pkthdr.rcvif = NULL; 707 n->m_len = 0; 708 maxhlen = M_TRAILINGSPACE(n) - maxlen; 709 mtx_lock(&hostname_mtx); 710 if (maxhlen > hostnamelen) 711 maxhlen = hostnamelen; 712 /* 713 * Copy IPv6 and ICMPv6 only. 714 */ 715 nip6 = mtod(n, struct ip6_hdr *); 716 bcopy(ip6, nip6, sizeof(struct ip6_hdr)); 717 nicmp6 = (struct icmp6_hdr *)(nip6 + 1); 718 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr)); 719 p = (u_char *)(nicmp6 + 1); 720 bzero(p, 4); 721 bcopy(V_hostname, p + 4, maxhlen); /* meaningless TTL */ 722 mtx_unlock(&hostname_mtx); 723 noff = sizeof(struct ip6_hdr); 724 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) + 725 sizeof(struct icmp6_hdr) + 4 + maxhlen; 726 nicmp6->icmp6_type = ICMP6_WRUREPLY; 727 nicmp6->icmp6_code = 0; 728 } 729 #undef hostnamelen 730 if (n) { 731 V_icmp6stat.icp6s_reflect++; 732 V_icmp6stat.icp6s_outhist[ICMP6_WRUREPLY]++; 733 icmp6_reflect(n, noff); 734 } 735 break; 736 } 737 738 case ICMP6_WRUREPLY: 739 if (code != 0) 740 goto badcode; 741 break; 742 743 case ND_ROUTER_SOLICIT: 744 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routersolicit); 745 if (code != 0) 746 goto badcode; 747 if (icmp6len < sizeof(struct nd_router_solicit)) 748 goto badlen; 749 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 750 /* give up local */ 751 nd6_rs_input(m, off, icmp6len); 752 m = NULL; 753 goto freeit; 754 } 755 nd6_rs_input(n, off, icmp6len); 756 /* m stays. */ 757 break; 758 759 case ND_ROUTER_ADVERT: 760 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routeradvert); 761 if (code != 0) 762 goto badcode; 763 if (icmp6len < sizeof(struct nd_router_advert)) 764 goto badlen; 765 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 766 /* give up local */ 767 nd6_ra_input(m, off, icmp6len); 768 m = NULL; 769 goto freeit; 770 } 771 nd6_ra_input(n, off, icmp6len); 772 /* m stays. */ 773 break; 774 775 case ND_NEIGHBOR_SOLICIT: 776 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighborsolicit); 777 if (code != 0) 778 goto badcode; 779 if (icmp6len < sizeof(struct nd_neighbor_solicit)) 780 goto badlen; 781 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 782 /* give up local */ 783 nd6_ns_input(m, off, icmp6len); 784 m = NULL; 785 goto freeit; 786 } 787 nd6_ns_input(n, off, icmp6len); 788 /* m stays. */ 789 break; 790 791 case ND_NEIGHBOR_ADVERT: 792 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighboradvert); 793 if (code != 0) 794 goto badcode; 795 if (icmp6len < sizeof(struct nd_neighbor_advert)) 796 goto badlen; 797 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 798 /* give up local */ 799 nd6_na_input(m, off, icmp6len); 800 m = NULL; 801 goto freeit; 802 } 803 nd6_na_input(n, off, icmp6len); 804 /* m stays. */ 805 break; 806 807 case ND_REDIRECT: 808 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_redirect); 809 if (code != 0) 810 goto badcode; 811 if (icmp6len < sizeof(struct nd_redirect)) 812 goto badlen; 813 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 814 /* give up local */ 815 icmp6_redirect_input(m, off); 816 m = NULL; 817 goto freeit; 818 } 819 icmp6_redirect_input(n, off); 820 /* m stays. */ 821 break; 822 823 case ICMP6_ROUTER_RENUMBERING: 824 if (code != ICMP6_ROUTER_RENUMBERING_COMMAND && 825 code != ICMP6_ROUTER_RENUMBERING_RESULT) 826 goto badcode; 827 if (icmp6len < sizeof(struct icmp6_router_renum)) 828 goto badlen; 829 break; 830 831 default: 832 nd6log((LOG_DEBUG, 833 "icmp6_input: unknown type %d(src=%s, dst=%s, ifid=%d)\n", 834 icmp6->icmp6_type, ip6_sprintf(ip6bufs, &ip6->ip6_src), 835 ip6_sprintf(ip6bufd, &ip6->ip6_dst), 836 m->m_pkthdr.rcvif ? m->m_pkthdr.rcvif->if_index : 0)); 837 if (icmp6->icmp6_type < ICMP6_ECHO_REQUEST) { 838 /* ICMPv6 error: MUST deliver it by spec... */ 839 code = PRC_NCMDS; 840 /* deliver */ 841 } else { 842 /* ICMPv6 informational: MUST not deliver */ 843 break; 844 } 845 deliver: 846 if (icmp6_notify_error(&m, off, icmp6len, code)) { 847 /* In this case, m should've been freed. */ 848 return (IPPROTO_DONE); 849 } 850 break; 851 852 badcode: 853 V_icmp6stat.icp6s_badcode++; 854 break; 855 856 badlen: 857 V_icmp6stat.icp6s_badlen++; 858 break; 859 } 860 861 /* deliver the packet to appropriate sockets */ 862 icmp6_rip6_input(&m, *offp); 863 864 return IPPROTO_DONE; 865 866 freeit: 867 m_freem(m); 868 return IPPROTO_DONE; 869 } 870 871 static int 872 icmp6_notify_error(struct mbuf **mp, int off, int icmp6len, int code) 873 { 874 INIT_VNET_INET6(curvnet); 875 struct mbuf *m = *mp; 876 struct icmp6_hdr *icmp6; 877 struct ip6_hdr *eip6; 878 u_int32_t notifymtu; 879 struct sockaddr_in6 icmp6src, icmp6dst; 880 881 if (icmp6len < sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr)) { 882 V_icmp6stat.icp6s_tooshort++; 883 goto freeit; 884 } 885 #ifndef PULLDOWN_TEST 886 IP6_EXTHDR_CHECK(m, off, 887 sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr), -1); 888 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 889 #else 890 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, 891 sizeof(*icmp6) + sizeof(struct ip6_hdr)); 892 if (icmp6 == NULL) { 893 V_icmp6stat.icp6s_tooshort++; 894 return (-1); 895 } 896 #endif 897 eip6 = (struct ip6_hdr *)(icmp6 + 1); 898 899 /* Detect the upper level protocol */ 900 { 901 void (*ctlfunc)(int, struct sockaddr *, void *); 902 u_int8_t nxt = eip6->ip6_nxt; 903 int eoff = off + sizeof(struct icmp6_hdr) + 904 sizeof(struct ip6_hdr); 905 struct ip6ctlparam ip6cp; 906 struct in6_addr *finaldst = NULL; 907 int icmp6type = icmp6->icmp6_type; 908 struct ip6_frag *fh; 909 struct ip6_rthdr *rth; 910 struct ip6_rthdr0 *rth0; 911 int rthlen; 912 913 while (1) { /* XXX: should avoid infinite loop explicitly? */ 914 struct ip6_ext *eh; 915 916 switch (nxt) { 917 case IPPROTO_HOPOPTS: 918 case IPPROTO_DSTOPTS: 919 case IPPROTO_AH: 920 #ifndef PULLDOWN_TEST 921 IP6_EXTHDR_CHECK(m, 0, 922 eoff + sizeof(struct ip6_ext), -1); 923 eh = (struct ip6_ext *)(mtod(m, caddr_t) + eoff); 924 #else 925 IP6_EXTHDR_GET(eh, struct ip6_ext *, m, 926 eoff, sizeof(*eh)); 927 if (eh == NULL) { 928 V_icmp6stat.icp6s_tooshort++; 929 return (-1); 930 } 931 #endif 932 933 if (nxt == IPPROTO_AH) 934 eoff += (eh->ip6e_len + 2) << 2; 935 else 936 eoff += (eh->ip6e_len + 1) << 3; 937 nxt = eh->ip6e_nxt; 938 break; 939 case IPPROTO_ROUTING: 940 /* 941 * When the erroneous packet contains a 942 * routing header, we should examine the 943 * header to determine the final destination. 944 * Otherwise, we can't properly update 945 * information that depends on the final 946 * destination (e.g. path MTU). 947 */ 948 #ifndef PULLDOWN_TEST 949 IP6_EXTHDR_CHECK(m, 0, eoff + sizeof(*rth), -1); 950 rth = (struct ip6_rthdr *) 951 (mtod(m, caddr_t) + eoff); 952 #else 953 IP6_EXTHDR_GET(rth, struct ip6_rthdr *, m, 954 eoff, sizeof(*rth)); 955 if (rth == NULL) { 956 V_icmp6stat.icp6s_tooshort++; 957 return (-1); 958 } 959 #endif 960 rthlen = (rth->ip6r_len + 1) << 3; 961 /* 962 * XXX: currently there is no 963 * officially defined type other 964 * than type-0. 965 * Note that if the segment left field 966 * is 0, all intermediate hops must 967 * have been passed. 968 */ 969 if (rth->ip6r_segleft && 970 rth->ip6r_type == IPV6_RTHDR_TYPE_0) { 971 int hops; 972 973 #ifndef PULLDOWN_TEST 974 IP6_EXTHDR_CHECK(m, 0, eoff + rthlen, -1); 975 rth0 = (struct ip6_rthdr0 *) 976 (mtod(m, caddr_t) + eoff); 977 #else 978 IP6_EXTHDR_GET(rth0, 979 struct ip6_rthdr0 *, m, 980 eoff, rthlen); 981 if (rth0 == NULL) { 982 V_icmp6stat.icp6s_tooshort++; 983 return (-1); 984 } 985 #endif 986 /* just ignore a bogus header */ 987 if ((rth0->ip6r0_len % 2) == 0 && 988 (hops = rth0->ip6r0_len/2)) 989 finaldst = (struct in6_addr *)(rth0 + 1) + (hops - 1); 990 } 991 eoff += rthlen; 992 nxt = rth->ip6r_nxt; 993 break; 994 case IPPROTO_FRAGMENT: 995 #ifndef PULLDOWN_TEST 996 IP6_EXTHDR_CHECK(m, 0, eoff + 997 sizeof(struct ip6_frag), -1); 998 fh = (struct ip6_frag *)(mtod(m, caddr_t) + 999 eoff); 1000 #else 1001 IP6_EXTHDR_GET(fh, struct ip6_frag *, m, 1002 eoff, sizeof(*fh)); 1003 if (fh == NULL) { 1004 V_icmp6stat.icp6s_tooshort++; 1005 return (-1); 1006 } 1007 #endif 1008 /* 1009 * Data after a fragment header is meaningless 1010 * unless it is the first fragment, but 1011 * we'll go to the notify label for path MTU 1012 * discovery. 1013 */ 1014 if (fh->ip6f_offlg & IP6F_OFF_MASK) 1015 goto notify; 1016 1017 eoff += sizeof(struct ip6_frag); 1018 nxt = fh->ip6f_nxt; 1019 break; 1020 default: 1021 /* 1022 * This case includes ESP and the No Next 1023 * Header. In such cases going to the notify 1024 * label does not have any meaning 1025 * (i.e. ctlfunc will be NULL), but we go 1026 * anyway since we might have to update 1027 * path MTU information. 1028 */ 1029 goto notify; 1030 } 1031 } 1032 notify: 1033 #ifndef PULLDOWN_TEST 1034 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 1035 #else 1036 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, 1037 sizeof(*icmp6) + sizeof(struct ip6_hdr)); 1038 if (icmp6 == NULL) { 1039 V_icmp6stat.icp6s_tooshort++; 1040 return (-1); 1041 } 1042 #endif 1043 1044 /* 1045 * retrieve parameters from the inner IPv6 header, and convert 1046 * them into sockaddr structures. 1047 * XXX: there is no guarantee that the source or destination 1048 * addresses of the inner packet are in the same scope as 1049 * the addresses of the icmp packet. But there is no other 1050 * way to determine the zone. 1051 */ 1052 eip6 = (struct ip6_hdr *)(icmp6 + 1); 1053 1054 bzero(&icmp6dst, sizeof(icmp6dst)); 1055 icmp6dst.sin6_len = sizeof(struct sockaddr_in6); 1056 icmp6dst.sin6_family = AF_INET6; 1057 if (finaldst == NULL) 1058 icmp6dst.sin6_addr = eip6->ip6_dst; 1059 else 1060 icmp6dst.sin6_addr = *finaldst; 1061 if (in6_setscope(&icmp6dst.sin6_addr, m->m_pkthdr.rcvif, NULL)) 1062 goto freeit; 1063 bzero(&icmp6src, sizeof(icmp6src)); 1064 icmp6src.sin6_len = sizeof(struct sockaddr_in6); 1065 icmp6src.sin6_family = AF_INET6; 1066 icmp6src.sin6_addr = eip6->ip6_src; 1067 if (in6_setscope(&icmp6src.sin6_addr, m->m_pkthdr.rcvif, NULL)) 1068 goto freeit; 1069 icmp6src.sin6_flowinfo = 1070 (eip6->ip6_flow & IPV6_FLOWLABEL_MASK); 1071 1072 if (finaldst == NULL) 1073 finaldst = &eip6->ip6_dst; 1074 ip6cp.ip6c_m = m; 1075 ip6cp.ip6c_icmp6 = icmp6; 1076 ip6cp.ip6c_ip6 = (struct ip6_hdr *)(icmp6 + 1); 1077 ip6cp.ip6c_off = eoff; 1078 ip6cp.ip6c_finaldst = finaldst; 1079 ip6cp.ip6c_src = &icmp6src; 1080 ip6cp.ip6c_nxt = nxt; 1081 1082 if (icmp6type == ICMP6_PACKET_TOO_BIG) { 1083 notifymtu = ntohl(icmp6->icmp6_mtu); 1084 ip6cp.ip6c_cmdarg = (void *)¬ifymtu; 1085 icmp6_mtudisc_update(&ip6cp, 1); /*XXX*/ 1086 } 1087 1088 ctlfunc = (void (*)(int, struct sockaddr *, void *)) 1089 (inet6sw[ip6_protox[nxt]].pr_ctlinput); 1090 if (ctlfunc) { 1091 (void) (*ctlfunc)(code, (struct sockaddr *)&icmp6dst, 1092 &ip6cp); 1093 } 1094 } 1095 *mp = m; 1096 return (0); 1097 1098 freeit: 1099 m_freem(m); 1100 return (-1); 1101 } 1102 1103 void 1104 icmp6_mtudisc_update(struct ip6ctlparam *ip6cp, int validated) 1105 { 1106 INIT_VNET_INET6(curvnet); 1107 struct in6_addr *dst = ip6cp->ip6c_finaldst; 1108 struct icmp6_hdr *icmp6 = ip6cp->ip6c_icmp6; 1109 struct mbuf *m = ip6cp->ip6c_m; /* will be necessary for scope issue */ 1110 u_int mtu = ntohl(icmp6->icmp6_mtu); 1111 struct in_conninfo inc; 1112 1113 #if 0 1114 /* 1115 * RFC2460 section 5, last paragraph. 1116 * even though minimum link MTU for IPv6 is IPV6_MMTU, 1117 * we may see ICMPv6 too big with mtu < IPV6_MMTU 1118 * due to packet translator in the middle. 1119 * see ip6_output() and ip6_getpmtu() "alwaysfrag" case for 1120 * special handling. 1121 */ 1122 if (mtu < IPV6_MMTU) 1123 return; 1124 #endif 1125 1126 /* 1127 * we reject ICMPv6 too big with abnormally small value. 1128 * XXX what is the good definition of "abnormally small"? 1129 */ 1130 if (mtu < sizeof(struct ip6_hdr) + sizeof(struct ip6_frag) + 8) 1131 return; 1132 1133 if (!validated) 1134 return; 1135 1136 /* 1137 * In case the suggested mtu is less than IPV6_MMTU, we 1138 * only need to remember that it was for above mentioned 1139 * "alwaysfrag" case. 1140 * Try to be as close to the spec as possible. 1141 */ 1142 if (mtu < IPV6_MMTU) 1143 mtu = IPV6_MMTU - 8; 1144 1145 bzero(&inc, sizeof(inc)); 1146 inc.inc_flags = 1; /* IPv6 */ 1147 inc.inc6_faddr = *dst; 1148 if (in6_setscope(&inc.inc6_faddr, m->m_pkthdr.rcvif, NULL)) 1149 return; 1150 1151 if (mtu < tcp_maxmtu6(&inc, NULL)) { 1152 tcp_hc_updatemtu(&inc, mtu); 1153 V_icmp6stat.icp6s_pmtuchg++; 1154 } 1155 } 1156 1157 /* 1158 * Process a Node Information Query packet, based on 1159 * draft-ietf-ipngwg-icmp-name-lookups-07. 1160 * 1161 * Spec incompatibilities: 1162 * - IPv6 Subject address handling 1163 * - IPv4 Subject address handling support missing 1164 * - Proxy reply (answer even if it's not for me) 1165 * - joins NI group address at in6_ifattach() time only, does not cope 1166 * with hostname changes by sethostname(3) 1167 */ 1168 #define hostnamelen strlen(V_hostname) 1169 static struct mbuf * 1170 ni6_input(struct mbuf *m, int off) 1171 { 1172 INIT_VNET_INET6(curvnet); 1173 INIT_VPROCG(TD_TO_VPROCG(curthread)); /* XXX V_hostname needs this */ 1174 struct icmp6_nodeinfo *ni6, *nni6; 1175 struct mbuf *n = NULL; 1176 u_int16_t qtype; 1177 int subjlen; 1178 int replylen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo); 1179 struct ni_reply_fqdn *fqdn; 1180 int addrs; /* for NI_QTYPE_NODEADDR */ 1181 struct ifnet *ifp = NULL; /* for NI_QTYPE_NODEADDR */ 1182 struct in6_addr in6_subj; /* subject address */ 1183 struct ip6_hdr *ip6; 1184 int oldfqdn = 0; /* if 1, return pascal string (03 draft) */ 1185 char *subj = NULL; 1186 struct in6_ifaddr *ia6 = NULL; 1187 1188 ip6 = mtod(m, struct ip6_hdr *); 1189 #ifndef PULLDOWN_TEST 1190 ni6 = (struct icmp6_nodeinfo *)(mtod(m, caddr_t) + off); 1191 #else 1192 IP6_EXTHDR_GET(ni6, struct icmp6_nodeinfo *, m, off, sizeof(*ni6)); 1193 if (ni6 == NULL) { 1194 /* m is already reclaimed */ 1195 return (NULL); 1196 } 1197 #endif 1198 1199 /* 1200 * Validate IPv6 source address. 1201 * The default configuration MUST be to refuse answering queries from 1202 * global-scope addresses according to RFC4602. 1203 * Notes: 1204 * - it's not very clear what "refuse" means; this implementation 1205 * simply drops it. 1206 * - it's not very easy to identify global-scope (unicast) addresses 1207 * since there are many prefixes for them. It should be safer 1208 * and in practice sufficient to check "all" but loopback and 1209 * link-local (note that site-local unicast was deprecated and 1210 * ULA is defined as global scope-wise) 1211 */ 1212 if ((V_icmp6_nodeinfo & ICMP6_NODEINFO_GLOBALOK) == 0 && 1213 !IN6_IS_ADDR_LOOPBACK(&ip6->ip6_src) && 1214 !IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_src)) 1215 goto bad; 1216 1217 /* 1218 * Validate IPv6 destination address. 1219 * 1220 * The Responder must discard the Query without further processing 1221 * unless it is one of the Responder's unicast or anycast addresses, or 1222 * a link-local scope multicast address which the Responder has joined. 1223 * [RFC4602, Section 5.] 1224 */ 1225 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 1226 if (!IN6_IS_ADDR_MC_LINKLOCAL(&ip6->ip6_dst)) 1227 goto bad; 1228 /* else it's a link-local multicast, fine */ 1229 } else { /* unicast or anycast */ 1230 if ((ia6 = ip6_getdstifaddr(m)) == NULL) 1231 goto bad; /* XXX impossible */ 1232 1233 if ((ia6->ia6_flags & IN6_IFF_TEMPORARY) && 1234 !(V_icmp6_nodeinfo & ICMP6_NODEINFO_TMPADDROK)) { 1235 nd6log((LOG_DEBUG, "ni6_input: ignore node info to " 1236 "a temporary address in %s:%d", 1237 __FILE__, __LINE__)); 1238 goto bad; 1239 } 1240 } 1241 1242 /* validate query Subject field. */ 1243 qtype = ntohs(ni6->ni_qtype); 1244 subjlen = m->m_pkthdr.len - off - sizeof(struct icmp6_nodeinfo); 1245 switch (qtype) { 1246 case NI_QTYPE_NOOP: 1247 case NI_QTYPE_SUPTYPES: 1248 /* 07 draft */ 1249 if (ni6->ni_code == ICMP6_NI_SUBJ_FQDN && subjlen == 0) 1250 break; 1251 /* FALLTHROUGH */ 1252 case NI_QTYPE_FQDN: 1253 case NI_QTYPE_NODEADDR: 1254 case NI_QTYPE_IPV4ADDR: 1255 switch (ni6->ni_code) { 1256 case ICMP6_NI_SUBJ_IPV6: 1257 #if ICMP6_NI_SUBJ_IPV6 != 0 1258 case 0: 1259 #endif 1260 /* 1261 * backward compatibility - try to accept 03 draft 1262 * format, where no Subject is present. 1263 */ 1264 if (qtype == NI_QTYPE_FQDN && ni6->ni_code == 0 && 1265 subjlen == 0) { 1266 oldfqdn++; 1267 break; 1268 } 1269 #if ICMP6_NI_SUBJ_IPV6 != 0 1270 if (ni6->ni_code != ICMP6_NI_SUBJ_IPV6) 1271 goto bad; 1272 #endif 1273 1274 if (subjlen != sizeof(struct in6_addr)) 1275 goto bad; 1276 1277 /* 1278 * Validate Subject address. 1279 * 1280 * Not sure what exactly "address belongs to the node" 1281 * means in the spec, is it just unicast, or what? 1282 * 1283 * At this moment we consider Subject address as 1284 * "belong to the node" if the Subject address equals 1285 * to the IPv6 destination address; validation for 1286 * IPv6 destination address should have done enough 1287 * check for us. 1288 * 1289 * We do not do proxy at this moment. 1290 */ 1291 /* m_pulldown instead of copy? */ 1292 m_copydata(m, off + sizeof(struct icmp6_nodeinfo), 1293 subjlen, (caddr_t)&in6_subj); 1294 if (in6_setscope(&in6_subj, m->m_pkthdr.rcvif, NULL)) 1295 goto bad; 1296 1297 subj = (char *)&in6_subj; 1298 if (IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, &in6_subj)) 1299 break; 1300 1301 /* 1302 * XXX if we are to allow other cases, we should really 1303 * be careful about scope here. 1304 * basically, we should disallow queries toward IPv6 1305 * destination X with subject Y, 1306 * if scope(X) > scope(Y). 1307 * if we allow scope(X) > scope(Y), it will result in 1308 * information leakage across scope boundary. 1309 */ 1310 goto bad; 1311 1312 case ICMP6_NI_SUBJ_FQDN: 1313 /* 1314 * Validate Subject name with gethostname(3). 1315 * 1316 * The behavior may need some debate, since: 1317 * - we are not sure if the node has FQDN as 1318 * hostname (returned by gethostname(3)). 1319 * - the code does wildcard match for truncated names. 1320 * however, we are not sure if we want to perform 1321 * wildcard match, if gethostname(3) side has 1322 * truncated hostname. 1323 */ 1324 mtx_lock(&hostname_mtx); 1325 n = ni6_nametodns(V_hostname, hostnamelen, 0); 1326 mtx_unlock(&hostname_mtx); 1327 if (!n || n->m_next || n->m_len == 0) 1328 goto bad; 1329 IP6_EXTHDR_GET(subj, char *, m, 1330 off + sizeof(struct icmp6_nodeinfo), subjlen); 1331 if (subj == NULL) 1332 goto bad; 1333 if (!ni6_dnsmatch(subj, subjlen, mtod(n, const char *), 1334 n->m_len)) { 1335 goto bad; 1336 } 1337 m_freem(n); 1338 n = NULL; 1339 break; 1340 1341 case ICMP6_NI_SUBJ_IPV4: /* XXX: to be implemented? */ 1342 default: 1343 goto bad; 1344 } 1345 break; 1346 } 1347 1348 /* refuse based on configuration. XXX ICMP6_NI_REFUSED? */ 1349 switch (qtype) { 1350 case NI_QTYPE_FQDN: 1351 if ((V_icmp6_nodeinfo & ICMP6_NODEINFO_FQDNOK) == 0) 1352 goto bad; 1353 break; 1354 case NI_QTYPE_NODEADDR: 1355 case NI_QTYPE_IPV4ADDR: 1356 if ((V_icmp6_nodeinfo & ICMP6_NODEINFO_NODEADDROK) == 0) 1357 goto bad; 1358 break; 1359 } 1360 1361 /* guess reply length */ 1362 switch (qtype) { 1363 case NI_QTYPE_NOOP: 1364 break; /* no reply data */ 1365 case NI_QTYPE_SUPTYPES: 1366 replylen += sizeof(u_int32_t); 1367 break; 1368 case NI_QTYPE_FQDN: 1369 /* XXX will append an mbuf */ 1370 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1371 break; 1372 case NI_QTYPE_NODEADDR: 1373 addrs = ni6_addrs(ni6, m, &ifp, (struct in6_addr *)subj); 1374 if ((replylen += addrs * (sizeof(struct in6_addr) + 1375 sizeof(u_int32_t))) > MCLBYTES) 1376 replylen = MCLBYTES; /* XXX: will truncate pkt later */ 1377 break; 1378 case NI_QTYPE_IPV4ADDR: 1379 /* unsupported - should respond with unknown Qtype? */ 1380 break; 1381 default: 1382 /* 1383 * XXX: We must return a reply with the ICMP6 code 1384 * `unknown Qtype' in this case. However we regard the case 1385 * as an FQDN query for backward compatibility. 1386 * Older versions set a random value to this field, 1387 * so it rarely varies in the defined qtypes. 1388 * But the mechanism is not reliable... 1389 * maybe we should obsolete older versions. 1390 */ 1391 qtype = NI_QTYPE_FQDN; 1392 /* XXX will append an mbuf */ 1393 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1394 oldfqdn++; 1395 break; 1396 } 1397 1398 /* allocate an mbuf to reply. */ 1399 MGETHDR(n, M_DONTWAIT, m->m_type); 1400 if (n == NULL) { 1401 m_freem(m); 1402 return (NULL); 1403 } 1404 M_MOVE_PKTHDR(n, m); /* just for recvif */ 1405 if (replylen > MHLEN) { 1406 if (replylen > MCLBYTES) { 1407 /* 1408 * XXX: should we try to allocate more? But MCLBYTES 1409 * is probably much larger than IPV6_MMTU... 1410 */ 1411 goto bad; 1412 } 1413 MCLGET(n, M_DONTWAIT); 1414 if ((n->m_flags & M_EXT) == 0) { 1415 goto bad; 1416 } 1417 } 1418 n->m_pkthdr.len = n->m_len = replylen; 1419 1420 /* copy mbuf header and IPv6 + Node Information base headers */ 1421 bcopy(mtod(m, caddr_t), mtod(n, caddr_t), sizeof(struct ip6_hdr)); 1422 nni6 = (struct icmp6_nodeinfo *)(mtod(n, struct ip6_hdr *) + 1); 1423 bcopy((caddr_t)ni6, (caddr_t)nni6, sizeof(struct icmp6_nodeinfo)); 1424 1425 /* qtype dependent procedure */ 1426 switch (qtype) { 1427 case NI_QTYPE_NOOP: 1428 nni6->ni_code = ICMP6_NI_SUCCESS; 1429 nni6->ni_flags = 0; 1430 break; 1431 case NI_QTYPE_SUPTYPES: 1432 { 1433 u_int32_t v; 1434 nni6->ni_code = ICMP6_NI_SUCCESS; 1435 nni6->ni_flags = htons(0x0000); /* raw bitmap */ 1436 /* supports NOOP, SUPTYPES, FQDN, and NODEADDR */ 1437 v = (u_int32_t)htonl(0x0000000f); 1438 bcopy(&v, nni6 + 1, sizeof(u_int32_t)); 1439 break; 1440 } 1441 case NI_QTYPE_FQDN: 1442 nni6->ni_code = ICMP6_NI_SUCCESS; 1443 fqdn = (struct ni_reply_fqdn *)(mtod(n, caddr_t) + 1444 sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo)); 1445 nni6->ni_flags = 0; /* XXX: meaningless TTL */ 1446 fqdn->ni_fqdn_ttl = 0; /* ditto. */ 1447 /* 1448 * XXX do we really have FQDN in variable "hostname"? 1449 */ 1450 mtx_lock(&hostname_mtx); 1451 n->m_next = ni6_nametodns(V_hostname, hostnamelen, oldfqdn); 1452 mtx_unlock(&hostname_mtx); 1453 if (n->m_next == NULL) 1454 goto bad; 1455 /* XXX we assume that n->m_next is not a chain */ 1456 if (n->m_next->m_next != NULL) 1457 goto bad; 1458 n->m_pkthdr.len += n->m_next->m_len; 1459 break; 1460 case NI_QTYPE_NODEADDR: 1461 { 1462 int lenlim, copied; 1463 1464 nni6->ni_code = ICMP6_NI_SUCCESS; 1465 n->m_pkthdr.len = n->m_len = 1466 sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo); 1467 lenlim = M_TRAILINGSPACE(n); 1468 copied = ni6_store_addrs(ni6, nni6, ifp, lenlim); 1469 /* XXX: reset mbuf length */ 1470 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) + 1471 sizeof(struct icmp6_nodeinfo) + copied; 1472 break; 1473 } 1474 default: 1475 break; /* XXX impossible! */ 1476 } 1477 1478 nni6->ni_type = ICMP6_NI_REPLY; 1479 m_freem(m); 1480 return (n); 1481 1482 bad: 1483 m_freem(m); 1484 if (n) 1485 m_freem(n); 1486 return (NULL); 1487 } 1488 #undef hostnamelen 1489 1490 /* 1491 * make a mbuf with DNS-encoded string. no compression support. 1492 * 1493 * XXX names with less than 2 dots (like "foo" or "foo.section") will be 1494 * treated as truncated name (two \0 at the end). this is a wild guess. 1495 * 1496 * old - return pascal string if non-zero 1497 */ 1498 static struct mbuf * 1499 ni6_nametodns(const char *name, int namelen, int old) 1500 { 1501 struct mbuf *m; 1502 char *cp, *ep; 1503 const char *p, *q; 1504 int i, len, nterm; 1505 1506 if (old) 1507 len = namelen + 1; 1508 else 1509 len = MCLBYTES; 1510 1511 /* because MAXHOSTNAMELEN is usually 256, we use cluster mbuf */ 1512 MGET(m, M_DONTWAIT, MT_DATA); 1513 if (m && len > MLEN) { 1514 MCLGET(m, M_DONTWAIT); 1515 if ((m->m_flags & M_EXT) == 0) 1516 goto fail; 1517 } 1518 if (!m) 1519 goto fail; 1520 m->m_next = NULL; 1521 1522 if (old) { 1523 m->m_len = len; 1524 *mtod(m, char *) = namelen; 1525 bcopy(name, mtod(m, char *) + 1, namelen); 1526 return m; 1527 } else { 1528 m->m_len = 0; 1529 cp = mtod(m, char *); 1530 ep = mtod(m, char *) + M_TRAILINGSPACE(m); 1531 1532 /* if not certain about my name, return empty buffer */ 1533 if (namelen == 0) 1534 return m; 1535 1536 /* 1537 * guess if it looks like shortened hostname, or FQDN. 1538 * shortened hostname needs two trailing "\0". 1539 */ 1540 i = 0; 1541 for (p = name; p < name + namelen; p++) { 1542 if (*p && *p == '.') 1543 i++; 1544 } 1545 if (i < 2) 1546 nterm = 2; 1547 else 1548 nterm = 1; 1549 1550 p = name; 1551 while (cp < ep && p < name + namelen) { 1552 i = 0; 1553 for (q = p; q < name + namelen && *q && *q != '.'; q++) 1554 i++; 1555 /* result does not fit into mbuf */ 1556 if (cp + i + 1 >= ep) 1557 goto fail; 1558 /* 1559 * DNS label length restriction, RFC1035 page 8. 1560 * "i == 0" case is included here to avoid returning 1561 * 0-length label on "foo..bar". 1562 */ 1563 if (i <= 0 || i >= 64) 1564 goto fail; 1565 *cp++ = i; 1566 bcopy(p, cp, i); 1567 cp += i; 1568 p = q; 1569 if (p < name + namelen && *p == '.') 1570 p++; 1571 } 1572 /* termination */ 1573 if (cp + nterm >= ep) 1574 goto fail; 1575 while (nterm-- > 0) 1576 *cp++ = '\0'; 1577 m->m_len = cp - mtod(m, char *); 1578 return m; 1579 } 1580 1581 panic("should not reach here"); 1582 /* NOTREACHED */ 1583 1584 fail: 1585 if (m) 1586 m_freem(m); 1587 return NULL; 1588 } 1589 1590 /* 1591 * check if two DNS-encoded string matches. takes care of truncated 1592 * form (with \0\0 at the end). no compression support. 1593 * XXX upper/lowercase match (see RFC2065) 1594 */ 1595 static int 1596 ni6_dnsmatch(const char *a, int alen, const char *b, int blen) 1597 { 1598 const char *a0, *b0; 1599 int l; 1600 1601 /* simplest case - need validation? */ 1602 if (alen == blen && bcmp(a, b, alen) == 0) 1603 return 1; 1604 1605 a0 = a; 1606 b0 = b; 1607 1608 /* termination is mandatory */ 1609 if (alen < 2 || blen < 2) 1610 return 0; 1611 if (a0[alen - 1] != '\0' || b0[blen - 1] != '\0') 1612 return 0; 1613 alen--; 1614 blen--; 1615 1616 while (a - a0 < alen && b - b0 < blen) { 1617 if (a - a0 + 1 > alen || b - b0 + 1 > blen) 1618 return 0; 1619 1620 if ((signed char)a[0] < 0 || (signed char)b[0] < 0) 1621 return 0; 1622 /* we don't support compression yet */ 1623 if (a[0] >= 64 || b[0] >= 64) 1624 return 0; 1625 1626 /* truncated case */ 1627 if (a[0] == 0 && a - a0 == alen - 1) 1628 return 1; 1629 if (b[0] == 0 && b - b0 == blen - 1) 1630 return 1; 1631 if (a[0] == 0 || b[0] == 0) 1632 return 0; 1633 1634 if (a[0] != b[0]) 1635 return 0; 1636 l = a[0]; 1637 if (a - a0 + 1 + l > alen || b - b0 + 1 + l > blen) 1638 return 0; 1639 if (bcmp(a + 1, b + 1, l) != 0) 1640 return 0; 1641 1642 a += 1 + l; 1643 b += 1 + l; 1644 } 1645 1646 if (a - a0 == alen && b - b0 == blen) 1647 return 1; 1648 else 1649 return 0; 1650 } 1651 1652 /* 1653 * calculate the number of addresses to be returned in the node info reply. 1654 */ 1655 static int 1656 ni6_addrs(struct icmp6_nodeinfo *ni6, struct mbuf *m, struct ifnet **ifpp, 1657 struct in6_addr *subj) 1658 { 1659 INIT_VNET_NET(curvnet); 1660 INIT_VNET_INET6(curvnet); 1661 struct ifnet *ifp; 1662 struct in6_ifaddr *ifa6; 1663 struct ifaddr *ifa; 1664 int addrs = 0, addrsofif, iffound = 0; 1665 int niflags = ni6->ni_flags; 1666 1667 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0) { 1668 switch (ni6->ni_code) { 1669 case ICMP6_NI_SUBJ_IPV6: 1670 if (subj == NULL) /* must be impossible... */ 1671 return (0); 1672 break; 1673 default: 1674 /* 1675 * XXX: we only support IPv6 subject address for 1676 * this Qtype. 1677 */ 1678 return (0); 1679 } 1680 } 1681 1682 IFNET_RLOCK(); 1683 for (ifp = TAILQ_FIRST(&V_ifnet); ifp; ifp = TAILQ_NEXT(ifp, if_list)) { 1684 addrsofif = 0; 1685 TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list) { 1686 if (ifa->ifa_addr->sa_family != AF_INET6) 1687 continue; 1688 ifa6 = (struct in6_ifaddr *)ifa; 1689 1690 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0 && 1691 IN6_ARE_ADDR_EQUAL(subj, &ifa6->ia_addr.sin6_addr)) 1692 iffound = 1; 1693 1694 /* 1695 * IPv4-mapped addresses can only be returned by a 1696 * Node Information proxy, since they represent 1697 * addresses of IPv4-only nodes, which perforce do 1698 * not implement this protocol. 1699 * [icmp-name-lookups-07, Section 5.4] 1700 * So we don't support NI_NODEADDR_FLAG_COMPAT in 1701 * this function at this moment. 1702 */ 1703 1704 /* What do we have to do about ::1? */ 1705 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1706 case IPV6_ADDR_SCOPE_LINKLOCAL: 1707 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0) 1708 continue; 1709 break; 1710 case IPV6_ADDR_SCOPE_SITELOCAL: 1711 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0) 1712 continue; 1713 break; 1714 case IPV6_ADDR_SCOPE_GLOBAL: 1715 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0) 1716 continue; 1717 break; 1718 default: 1719 continue; 1720 } 1721 1722 /* 1723 * check if anycast is okay. 1724 * XXX: just experimental. not in the spec. 1725 */ 1726 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 && 1727 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0) 1728 continue; /* we need only unicast addresses */ 1729 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 1730 (V_icmp6_nodeinfo & ICMP6_NODEINFO_TMPADDROK) == 0) { 1731 continue; 1732 } 1733 addrsofif++; /* count the address */ 1734 } 1735 if (iffound) { 1736 *ifpp = ifp; 1737 IFNET_RUNLOCK(); 1738 return (addrsofif); 1739 } 1740 1741 addrs += addrsofif; 1742 } 1743 IFNET_RUNLOCK(); 1744 1745 return (addrs); 1746 } 1747 1748 static int 1749 ni6_store_addrs(struct icmp6_nodeinfo *ni6, struct icmp6_nodeinfo *nni6, 1750 struct ifnet *ifp0, int resid) 1751 { 1752 INIT_VNET_NET(curvnet); 1753 INIT_VNET_INET6(curvnet); 1754 struct ifnet *ifp = ifp0 ? ifp0 : TAILQ_FIRST(&V_ifnet); 1755 struct in6_ifaddr *ifa6; 1756 struct ifaddr *ifa; 1757 struct ifnet *ifp_dep = NULL; 1758 int copied = 0, allow_deprecated = 0; 1759 u_char *cp = (u_char *)(nni6 + 1); 1760 int niflags = ni6->ni_flags; 1761 u_int32_t ltime; 1762 1763 if (ifp0 == NULL && !(niflags & NI_NODEADDR_FLAG_ALL)) 1764 return (0); /* needless to copy */ 1765 1766 IFNET_RLOCK(); 1767 again: 1768 1769 for (; ifp; ifp = TAILQ_NEXT(ifp, if_list)) { 1770 for (ifa = ifp->if_addrlist.tqh_first; ifa; 1771 ifa = ifa->ifa_list.tqe_next) { 1772 if (ifa->ifa_addr->sa_family != AF_INET6) 1773 continue; 1774 ifa6 = (struct in6_ifaddr *)ifa; 1775 1776 if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) != 0 && 1777 allow_deprecated == 0) { 1778 /* 1779 * prefererred address should be put before 1780 * deprecated addresses. 1781 */ 1782 1783 /* record the interface for later search */ 1784 if (ifp_dep == NULL) 1785 ifp_dep = ifp; 1786 1787 continue; 1788 } else if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) == 0 && 1789 allow_deprecated != 0) 1790 continue; /* we now collect deprecated addrs */ 1791 1792 /* What do we have to do about ::1? */ 1793 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1794 case IPV6_ADDR_SCOPE_LINKLOCAL: 1795 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0) 1796 continue; 1797 break; 1798 case IPV6_ADDR_SCOPE_SITELOCAL: 1799 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0) 1800 continue; 1801 break; 1802 case IPV6_ADDR_SCOPE_GLOBAL: 1803 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0) 1804 continue; 1805 break; 1806 default: 1807 continue; 1808 } 1809 1810 /* 1811 * check if anycast is okay. 1812 * XXX: just experimental. not in the spec. 1813 */ 1814 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 && 1815 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0) 1816 continue; 1817 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 1818 (V_icmp6_nodeinfo & ICMP6_NODEINFO_TMPADDROK) == 0) { 1819 continue; 1820 } 1821 1822 /* now we can copy the address */ 1823 if (resid < sizeof(struct in6_addr) + 1824 sizeof(u_int32_t)) { 1825 /* 1826 * We give up much more copy. 1827 * Set the truncate flag and return. 1828 */ 1829 nni6->ni_flags |= NI_NODEADDR_FLAG_TRUNCATE; 1830 IFNET_RUNLOCK(); 1831 return (copied); 1832 } 1833 1834 /* 1835 * Set the TTL of the address. 1836 * The TTL value should be one of the following 1837 * according to the specification: 1838 * 1839 * 1. The remaining lifetime of a DHCP lease on the 1840 * address, or 1841 * 2. The remaining Valid Lifetime of a prefix from 1842 * which the address was derived through Stateless 1843 * Autoconfiguration. 1844 * 1845 * Note that we currently do not support stateful 1846 * address configuration by DHCPv6, so the former 1847 * case can't happen. 1848 */ 1849 if (ifa6->ia6_lifetime.ia6t_expire == 0) 1850 ltime = ND6_INFINITE_LIFETIME; 1851 else { 1852 if (ifa6->ia6_lifetime.ia6t_expire > 1853 time_second) 1854 ltime = htonl(ifa6->ia6_lifetime.ia6t_expire - time_second); 1855 else 1856 ltime = 0; 1857 } 1858 1859 bcopy(<ime, cp, sizeof(u_int32_t)); 1860 cp += sizeof(u_int32_t); 1861 1862 /* copy the address itself */ 1863 bcopy(&ifa6->ia_addr.sin6_addr, cp, 1864 sizeof(struct in6_addr)); 1865 in6_clearscope((struct in6_addr *)cp); /* XXX */ 1866 cp += sizeof(struct in6_addr); 1867 1868 resid -= (sizeof(struct in6_addr) + sizeof(u_int32_t)); 1869 copied += (sizeof(struct in6_addr) + sizeof(u_int32_t)); 1870 } 1871 if (ifp0) /* we need search only on the specified IF */ 1872 break; 1873 } 1874 1875 if (allow_deprecated == 0 && ifp_dep != NULL) { 1876 ifp = ifp_dep; 1877 allow_deprecated = 1; 1878 1879 goto again; 1880 } 1881 1882 IFNET_RUNLOCK(); 1883 1884 return (copied); 1885 } 1886 1887 /* 1888 * XXX almost dup'ed code with rip6_input. 1889 */ 1890 static int 1891 icmp6_rip6_input(struct mbuf **mp, int off) 1892 { 1893 INIT_VNET_INET(curvnet); 1894 INIT_VNET_INET6(curvnet); 1895 struct mbuf *m = *mp; 1896 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1897 struct in6pcb *in6p; 1898 struct in6pcb *last = NULL; 1899 struct sockaddr_in6 fromsa; 1900 struct icmp6_hdr *icmp6; 1901 struct mbuf *opts = NULL; 1902 1903 #ifndef PULLDOWN_TEST 1904 /* this is assumed to be safe. */ 1905 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off); 1906 #else 1907 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 1908 if (icmp6 == NULL) { 1909 /* m is already reclaimed */ 1910 return (IPPROTO_DONE); 1911 } 1912 #endif 1913 1914 /* 1915 * XXX: the address may have embedded scope zone ID, which should be 1916 * hidden from applications. 1917 */ 1918 bzero(&fromsa, sizeof(fromsa)); 1919 fromsa.sin6_family = AF_INET6; 1920 fromsa.sin6_len = sizeof(struct sockaddr_in6); 1921 fromsa.sin6_addr = ip6->ip6_src; 1922 if (sa6_recoverscope(&fromsa)) { 1923 m_freem(m); 1924 return (IPPROTO_DONE); 1925 } 1926 1927 INP_INFO_RLOCK(&V_ripcbinfo); 1928 LIST_FOREACH(in6p, &V_ripcb, inp_list) { 1929 if ((in6p->inp_vflag & INP_IPV6) == 0) 1930 continue; 1931 if (in6p->in6p_ip6_nxt != IPPROTO_ICMPV6) 1932 continue; 1933 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr) && 1934 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr, &ip6->ip6_dst)) 1935 continue; 1936 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr) && 1937 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr, &ip6->ip6_src)) 1938 continue; 1939 INP_RLOCK(in6p); 1940 if (ICMP6_FILTER_WILLBLOCK(icmp6->icmp6_type, 1941 in6p->in6p_icmp6filt)) { 1942 INP_RUNLOCK(in6p); 1943 continue; 1944 } 1945 if (last) { 1946 struct mbuf *n = NULL; 1947 1948 /* 1949 * Recent network drivers tend to allocate a single 1950 * mbuf cluster, rather than to make a couple of 1951 * mbufs without clusters. Also, since the IPv6 code 1952 * path tries to avoid m_pullup(), it is highly 1953 * probable that we still have an mbuf cluster here 1954 * even though the necessary length can be stored in an 1955 * mbuf's internal buffer. 1956 * Meanwhile, the default size of the receive socket 1957 * buffer for raw sockets is not so large. This means 1958 * the possibility of packet loss is relatively higher 1959 * than before. To avoid this scenario, we copy the 1960 * received data to a separate mbuf that does not use 1961 * a cluster, if possible. 1962 * XXX: it is better to copy the data after stripping 1963 * intermediate headers. 1964 */ 1965 if ((m->m_flags & M_EXT) && m->m_next == NULL && 1966 m->m_len <= MHLEN) { 1967 MGET(n, M_DONTWAIT, m->m_type); 1968 if (n != NULL) { 1969 if (m_dup_pkthdr(n, m, M_NOWAIT)) { 1970 bcopy(m->m_data, n->m_data, 1971 m->m_len); 1972 n->m_len = m->m_len; 1973 } else { 1974 m_free(n); 1975 n = NULL; 1976 } 1977 } 1978 } 1979 if (n != NULL || 1980 (n = m_copy(m, 0, (int)M_COPYALL)) != NULL) { 1981 if (last->in6p_flags & IN6P_CONTROLOPTS) 1982 ip6_savecontrol(last, n, &opts); 1983 /* strip intermediate headers */ 1984 m_adj(n, off); 1985 SOCKBUF_LOCK(&last->in6p_socket->so_rcv); 1986 if (sbappendaddr_locked( 1987 &last->in6p_socket->so_rcv, 1988 (struct sockaddr *)&fromsa, n, opts) 1989 == 0) { 1990 /* should notify about lost packet */ 1991 m_freem(n); 1992 if (opts) { 1993 m_freem(opts); 1994 } 1995 SOCKBUF_UNLOCK( 1996 &last->in6p_socket->so_rcv); 1997 } else 1998 sorwakeup_locked(last->in6p_socket); 1999 opts = NULL; 2000 } 2001 INP_RUNLOCK(last); 2002 } 2003 last = in6p; 2004 } 2005 INP_INFO_RUNLOCK(&V_ripcbinfo); 2006 if (last) { 2007 if (last->in6p_flags & IN6P_CONTROLOPTS) 2008 ip6_savecontrol(last, m, &opts); 2009 /* strip intermediate headers */ 2010 m_adj(m, off); 2011 2012 /* avoid using mbuf clusters if possible (see above) */ 2013 if ((m->m_flags & M_EXT) && m->m_next == NULL && 2014 m->m_len <= MHLEN) { 2015 struct mbuf *n; 2016 2017 MGET(n, M_DONTWAIT, m->m_type); 2018 if (n != NULL) { 2019 if (m_dup_pkthdr(n, m, M_NOWAIT)) { 2020 bcopy(m->m_data, n->m_data, m->m_len); 2021 n->m_len = m->m_len; 2022 2023 m_freem(m); 2024 m = n; 2025 } else { 2026 m_freem(n); 2027 n = NULL; 2028 } 2029 } 2030 } 2031 SOCKBUF_LOCK(&last->in6p_socket->so_rcv); 2032 if (sbappendaddr_locked(&last->in6p_socket->so_rcv, 2033 (struct sockaddr *)&fromsa, m, opts) == 0) { 2034 m_freem(m); 2035 if (opts) 2036 m_freem(opts); 2037 SOCKBUF_UNLOCK(&last->in6p_socket->so_rcv); 2038 } else 2039 sorwakeup_locked(last->in6p_socket); 2040 INP_RUNLOCK(last); 2041 } else { 2042 m_freem(m); 2043 V_ip6stat.ip6s_delivered--; 2044 } 2045 return IPPROTO_DONE; 2046 } 2047 2048 /* 2049 * Reflect the ip6 packet back to the source. 2050 * OFF points to the icmp6 header, counted from the top of the mbuf. 2051 */ 2052 void 2053 icmp6_reflect(struct mbuf *m, size_t off) 2054 { 2055 INIT_VNET_INET6(curvnet); 2056 struct ip6_hdr *ip6; 2057 struct icmp6_hdr *icmp6; 2058 struct in6_ifaddr *ia; 2059 int plen; 2060 int type, code; 2061 struct ifnet *outif = NULL; 2062 struct in6_addr origdst, *src = NULL; 2063 2064 /* too short to reflect */ 2065 if (off < sizeof(struct ip6_hdr)) { 2066 nd6log((LOG_DEBUG, 2067 "sanity fail: off=%lx, sizeof(ip6)=%lx in %s:%d\n", 2068 (u_long)off, (u_long)sizeof(struct ip6_hdr), 2069 __FILE__, __LINE__)); 2070 goto bad; 2071 } 2072 2073 /* 2074 * If there are extra headers between IPv6 and ICMPv6, strip 2075 * off that header first. 2076 */ 2077 #ifdef DIAGNOSTIC 2078 if (sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) > MHLEN) 2079 panic("assumption failed in icmp6_reflect"); 2080 #endif 2081 if (off > sizeof(struct ip6_hdr)) { 2082 size_t l; 2083 struct ip6_hdr nip6; 2084 2085 l = off - sizeof(struct ip6_hdr); 2086 m_copydata(m, 0, sizeof(nip6), (caddr_t)&nip6); 2087 m_adj(m, l); 2088 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 2089 if (m->m_len < l) { 2090 if ((m = m_pullup(m, l)) == NULL) 2091 return; 2092 } 2093 bcopy((caddr_t)&nip6, mtod(m, caddr_t), sizeof(nip6)); 2094 } else /* off == sizeof(struct ip6_hdr) */ { 2095 size_t l; 2096 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 2097 if (m->m_len < l) { 2098 if ((m = m_pullup(m, l)) == NULL) 2099 return; 2100 } 2101 } 2102 plen = m->m_pkthdr.len - sizeof(struct ip6_hdr); 2103 ip6 = mtod(m, struct ip6_hdr *); 2104 ip6->ip6_nxt = IPPROTO_ICMPV6; 2105 icmp6 = (struct icmp6_hdr *)(ip6 + 1); 2106 type = icmp6->icmp6_type; /* keep type for statistics */ 2107 code = icmp6->icmp6_code; /* ditto. */ 2108 2109 origdst = ip6->ip6_dst; 2110 /* 2111 * ip6_input() drops a packet if its src is multicast. 2112 * So, the src is never multicast. 2113 */ 2114 ip6->ip6_dst = ip6->ip6_src; 2115 2116 /* 2117 * If the incoming packet was addressed directly to us (i.e. unicast), 2118 * use dst as the src for the reply. 2119 * The IN6_IFF_NOTREADY case should be VERY rare, but is possible 2120 * (for example) when we encounter an error while forwarding procedure 2121 * destined to a duplicated address of ours. 2122 * Note that ip6_getdstifaddr() may fail if we are in an error handling 2123 * procedure of an outgoing packet of our own, in which case we need 2124 * to search in the ifaddr list. 2125 */ 2126 if (!IN6_IS_ADDR_MULTICAST(&origdst)) { 2127 if ((ia = ip6_getdstifaddr(m))) { 2128 if (!(ia->ia6_flags & 2129 (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY))) 2130 src = &ia->ia_addr.sin6_addr; 2131 } else { 2132 struct sockaddr_in6 d; 2133 2134 bzero(&d, sizeof(d)); 2135 d.sin6_family = AF_INET6; 2136 d.sin6_len = sizeof(d); 2137 d.sin6_addr = origdst; 2138 ia = (struct in6_ifaddr *) 2139 ifa_ifwithaddr((struct sockaddr *)&d); 2140 if (ia && 2141 !(ia->ia6_flags & 2142 (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY))) { 2143 src = &ia->ia_addr.sin6_addr; 2144 } 2145 } 2146 } 2147 2148 if (src == NULL) { 2149 int e; 2150 struct sockaddr_in6 sin6; 2151 struct route_in6 ro; 2152 2153 /* 2154 * This case matches to multicasts, our anycast, or unicasts 2155 * that we do not own. Select a source address based on the 2156 * source address of the erroneous packet. 2157 */ 2158 bzero(&sin6, sizeof(sin6)); 2159 sin6.sin6_family = AF_INET6; 2160 sin6.sin6_len = sizeof(sin6); 2161 sin6.sin6_addr = ip6->ip6_dst; /* zone ID should be embedded */ 2162 2163 bzero(&ro, sizeof(ro)); 2164 src = in6_selectsrc(&sin6, NULL, NULL, &ro, NULL, &outif, &e); 2165 if (ro.ro_rt) 2166 RTFREE(ro.ro_rt); /* XXX: we could use this */ 2167 if (src == NULL) { 2168 char ip6buf[INET6_ADDRSTRLEN]; 2169 nd6log((LOG_DEBUG, 2170 "icmp6_reflect: source can't be determined: " 2171 "dst=%s, error=%d\n", 2172 ip6_sprintf(ip6buf, &sin6.sin6_addr), e)); 2173 goto bad; 2174 } 2175 } 2176 2177 ip6->ip6_src = *src; 2178 ip6->ip6_flow = 0; 2179 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2180 ip6->ip6_vfc |= IPV6_VERSION; 2181 ip6->ip6_nxt = IPPROTO_ICMPV6; 2182 if (outif) 2183 ip6->ip6_hlim = ND_IFINFO(outif)->chlim; 2184 else if (m->m_pkthdr.rcvif) { 2185 /* XXX: This may not be the outgoing interface */ 2186 ip6->ip6_hlim = ND_IFINFO(m->m_pkthdr.rcvif)->chlim; 2187 } else 2188 ip6->ip6_hlim = V_ip6_defhlim; 2189 2190 icmp6->icmp6_cksum = 0; 2191 icmp6->icmp6_cksum = in6_cksum(m, IPPROTO_ICMPV6, 2192 sizeof(struct ip6_hdr), plen); 2193 2194 /* 2195 * XXX option handling 2196 */ 2197 2198 m->m_flags &= ~(M_BCAST|M_MCAST); 2199 2200 ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL); 2201 if (outif) 2202 icmp6_ifoutstat_inc(outif, type, code); 2203 2204 return; 2205 2206 bad: 2207 m_freem(m); 2208 return; 2209 } 2210 2211 void 2212 icmp6_fasttimo(void) 2213 { 2214 2215 return; 2216 } 2217 2218 static const char * 2219 icmp6_redirect_diag(struct in6_addr *src6, struct in6_addr *dst6, 2220 struct in6_addr *tgt6) 2221 { 2222 static char buf[1024]; 2223 char ip6bufs[INET6_ADDRSTRLEN]; 2224 char ip6bufd[INET6_ADDRSTRLEN]; 2225 char ip6buft[INET6_ADDRSTRLEN]; 2226 snprintf(buf, sizeof(buf), "(src=%s dst=%s tgt=%s)", 2227 ip6_sprintf(ip6bufs, src6), ip6_sprintf(ip6bufd, dst6), 2228 ip6_sprintf(ip6buft, tgt6)); 2229 return buf; 2230 } 2231 2232 void 2233 icmp6_redirect_input(struct mbuf *m, int off) 2234 { 2235 INIT_VNET_INET6(curvnet); 2236 struct ifnet *ifp; 2237 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 2238 struct nd_redirect *nd_rd; 2239 int icmp6len = ntohs(ip6->ip6_plen); 2240 char *lladdr = NULL; 2241 int lladdrlen = 0; 2242 u_char *redirhdr = NULL; 2243 int redirhdrlen = 0; 2244 struct rtentry *rt = NULL; 2245 int is_router; 2246 int is_onlink; 2247 struct in6_addr src6 = ip6->ip6_src; 2248 struct in6_addr redtgt6; 2249 struct in6_addr reddst6; 2250 union nd_opts ndopts; 2251 char ip6buf[INET6_ADDRSTRLEN]; 2252 2253 if (!m) 2254 return; 2255 2256 ifp = m->m_pkthdr.rcvif; 2257 2258 if (!ifp) 2259 return; 2260 2261 /* XXX if we are router, we don't update route by icmp6 redirect */ 2262 if (V_ip6_forwarding) 2263 goto freeit; 2264 if (!V_icmp6_rediraccept) 2265 goto freeit; 2266 2267 #ifndef PULLDOWN_TEST 2268 IP6_EXTHDR_CHECK(m, off, icmp6len,); 2269 nd_rd = (struct nd_redirect *)((caddr_t)ip6 + off); 2270 #else 2271 IP6_EXTHDR_GET(nd_rd, struct nd_redirect *, m, off, icmp6len); 2272 if (nd_rd == NULL) { 2273 V_icmp6stat.icp6s_tooshort++; 2274 return; 2275 } 2276 #endif 2277 redtgt6 = nd_rd->nd_rd_target; 2278 reddst6 = nd_rd->nd_rd_dst; 2279 2280 if (in6_setscope(&redtgt6, m->m_pkthdr.rcvif, NULL) || 2281 in6_setscope(&reddst6, m->m_pkthdr.rcvif, NULL)) { 2282 goto freeit; 2283 } 2284 2285 /* validation */ 2286 if (!IN6_IS_ADDR_LINKLOCAL(&src6)) { 2287 nd6log((LOG_ERR, 2288 "ICMP6 redirect sent from %s rejected; " 2289 "must be from linklocal\n", 2290 ip6_sprintf(ip6buf, &src6))); 2291 goto bad; 2292 } 2293 if (ip6->ip6_hlim != 255) { 2294 nd6log((LOG_ERR, 2295 "ICMP6 redirect sent from %s rejected; " 2296 "hlim=%d (must be 255)\n", 2297 ip6_sprintf(ip6buf, &src6), ip6->ip6_hlim)); 2298 goto bad; 2299 } 2300 { 2301 /* ip6->ip6_src must be equal to gw for icmp6->icmp6_reddst */ 2302 struct sockaddr_in6 sin6; 2303 struct in6_addr *gw6; 2304 2305 bzero(&sin6, sizeof(sin6)); 2306 sin6.sin6_family = AF_INET6; 2307 sin6.sin6_len = sizeof(struct sockaddr_in6); 2308 bcopy(&reddst6, &sin6.sin6_addr, sizeof(reddst6)); 2309 rt = rtalloc1((struct sockaddr *)&sin6, 0, 0UL); 2310 if (rt) { 2311 if (rt->rt_gateway == NULL || 2312 rt->rt_gateway->sa_family != AF_INET6) { 2313 nd6log((LOG_ERR, 2314 "ICMP6 redirect rejected; no route " 2315 "with inet6 gateway found for redirect dst: %s\n", 2316 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2317 RTFREE_LOCKED(rt); 2318 goto bad; 2319 } 2320 2321 gw6 = &(((struct sockaddr_in6 *)rt->rt_gateway)->sin6_addr); 2322 if (bcmp(&src6, gw6, sizeof(struct in6_addr)) != 0) { 2323 nd6log((LOG_ERR, 2324 "ICMP6 redirect rejected; " 2325 "not equal to gw-for-src=%s (must be same): " 2326 "%s\n", 2327 ip6_sprintf(ip6buf, gw6), 2328 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2329 RTFREE_LOCKED(rt); 2330 goto bad; 2331 } 2332 } else { 2333 nd6log((LOG_ERR, 2334 "ICMP6 redirect rejected; " 2335 "no route found for redirect dst: %s\n", 2336 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2337 goto bad; 2338 } 2339 RTFREE_LOCKED(rt); 2340 rt = NULL; 2341 } 2342 if (IN6_IS_ADDR_MULTICAST(&reddst6)) { 2343 nd6log((LOG_ERR, 2344 "ICMP6 redirect rejected; " 2345 "redirect dst must be unicast: %s\n", 2346 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2347 goto bad; 2348 } 2349 2350 is_router = is_onlink = 0; 2351 if (IN6_IS_ADDR_LINKLOCAL(&redtgt6)) 2352 is_router = 1; /* router case */ 2353 if (bcmp(&redtgt6, &reddst6, sizeof(redtgt6)) == 0) 2354 is_onlink = 1; /* on-link destination case */ 2355 if (!is_router && !is_onlink) { 2356 nd6log((LOG_ERR, 2357 "ICMP6 redirect rejected; " 2358 "neither router case nor onlink case: %s\n", 2359 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2360 goto bad; 2361 } 2362 /* validation passed */ 2363 2364 icmp6len -= sizeof(*nd_rd); 2365 nd6_option_init(nd_rd + 1, icmp6len, &ndopts); 2366 if (nd6_options(&ndopts) < 0) { 2367 nd6log((LOG_INFO, "icmp6_redirect_input: " 2368 "invalid ND option, rejected: %s\n", 2369 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2370 /* nd6_options have incremented stats */ 2371 goto freeit; 2372 } 2373 2374 if (ndopts.nd_opts_tgt_lladdr) { 2375 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 2376 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 2377 } 2378 2379 if (ndopts.nd_opts_rh) { 2380 redirhdrlen = ndopts.nd_opts_rh->nd_opt_rh_len; 2381 redirhdr = (u_char *)(ndopts.nd_opts_rh + 1); /* xxx */ 2382 } 2383 2384 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 2385 nd6log((LOG_INFO, 2386 "icmp6_redirect_input: lladdrlen mismatch for %s " 2387 "(if %d, icmp6 packet %d): %s\n", 2388 ip6_sprintf(ip6buf, &redtgt6), 2389 ifp->if_addrlen, lladdrlen - 2, 2390 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2391 goto bad; 2392 } 2393 2394 /* RFC 2461 8.3 */ 2395 nd6_cache_lladdr(ifp, &redtgt6, lladdr, lladdrlen, ND_REDIRECT, 2396 is_onlink ? ND_REDIRECT_ONLINK : ND_REDIRECT_ROUTER); 2397 2398 if (!is_onlink) { /* better router case. perform rtredirect. */ 2399 /* perform rtredirect */ 2400 struct sockaddr_in6 sdst; 2401 struct sockaddr_in6 sgw; 2402 struct sockaddr_in6 ssrc; 2403 2404 bzero(&sdst, sizeof(sdst)); 2405 bzero(&sgw, sizeof(sgw)); 2406 bzero(&ssrc, sizeof(ssrc)); 2407 sdst.sin6_family = sgw.sin6_family = ssrc.sin6_family = AF_INET6; 2408 sdst.sin6_len = sgw.sin6_len = ssrc.sin6_len = 2409 sizeof(struct sockaddr_in6); 2410 bcopy(&redtgt6, &sgw.sin6_addr, sizeof(struct in6_addr)); 2411 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2412 bcopy(&src6, &ssrc.sin6_addr, sizeof(struct in6_addr)); 2413 rtredirect((struct sockaddr *)&sdst, (struct sockaddr *)&sgw, 2414 (struct sockaddr *)NULL, RTF_GATEWAY | RTF_HOST, 2415 (struct sockaddr *)&ssrc); 2416 } 2417 /* finally update cached route in each socket via pfctlinput */ 2418 { 2419 struct sockaddr_in6 sdst; 2420 2421 bzero(&sdst, sizeof(sdst)); 2422 sdst.sin6_family = AF_INET6; 2423 sdst.sin6_len = sizeof(struct sockaddr_in6); 2424 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2425 pfctlinput(PRC_REDIRECT_HOST, (struct sockaddr *)&sdst); 2426 #ifdef IPSEC 2427 key_sa_routechange((struct sockaddr *)&sdst); 2428 #endif /* IPSEC */ 2429 } 2430 2431 freeit: 2432 m_freem(m); 2433 return; 2434 2435 bad: 2436 V_icmp6stat.icp6s_badredirect++; 2437 m_freem(m); 2438 } 2439 2440 void 2441 icmp6_redirect_output(struct mbuf *m0, struct rtentry *rt) 2442 { 2443 INIT_VNET_INET6(curvnet); 2444 struct ifnet *ifp; /* my outgoing interface */ 2445 struct in6_addr *ifp_ll6; 2446 struct in6_addr *router_ll6; 2447 struct ip6_hdr *sip6; /* m0 as struct ip6_hdr */ 2448 struct mbuf *m = NULL; /* newly allocated one */ 2449 struct ip6_hdr *ip6; /* m as struct ip6_hdr */ 2450 struct nd_redirect *nd_rd; 2451 size_t maxlen; 2452 u_char *p; 2453 struct ifnet *outif = NULL; 2454 struct sockaddr_in6 src_sa; 2455 2456 icmp6_errcount(&V_icmp6stat.icp6s_outerrhist, ND_REDIRECT, 0); 2457 2458 /* if we are not router, we don't send icmp6 redirect */ 2459 if (!V_ip6_forwarding) 2460 goto fail; 2461 2462 /* sanity check */ 2463 if (!m0 || !rt || !(rt->rt_flags & RTF_UP) || !(ifp = rt->rt_ifp)) 2464 goto fail; 2465 2466 /* 2467 * Address check: 2468 * the source address must identify a neighbor, and 2469 * the destination address must not be a multicast address 2470 * [RFC 2461, sec 8.2] 2471 */ 2472 sip6 = mtod(m0, struct ip6_hdr *); 2473 bzero(&src_sa, sizeof(src_sa)); 2474 src_sa.sin6_family = AF_INET6; 2475 src_sa.sin6_len = sizeof(src_sa); 2476 src_sa.sin6_addr = sip6->ip6_src; 2477 if (nd6_is_addr_neighbor(&src_sa, ifp) == 0) 2478 goto fail; 2479 if (IN6_IS_ADDR_MULTICAST(&sip6->ip6_dst)) 2480 goto fail; /* what should we do here? */ 2481 2482 /* rate limit */ 2483 if (icmp6_ratelimit(&sip6->ip6_src, ND_REDIRECT, 0)) 2484 goto fail; 2485 2486 /* 2487 * Since we are going to append up to 1280 bytes (= IPV6_MMTU), 2488 * we almost always ask for an mbuf cluster for simplicity. 2489 * (MHLEN < IPV6_MMTU is almost always true) 2490 */ 2491 #if IPV6_MMTU >= MCLBYTES 2492 # error assumption failed about IPV6_MMTU and MCLBYTES 2493 #endif 2494 MGETHDR(m, M_DONTWAIT, MT_HEADER); 2495 if (m && IPV6_MMTU >= MHLEN) 2496 MCLGET(m, M_DONTWAIT); 2497 if (!m) 2498 goto fail; 2499 m->m_pkthdr.rcvif = NULL; 2500 m->m_len = 0; 2501 maxlen = M_TRAILINGSPACE(m); 2502 maxlen = min(IPV6_MMTU, maxlen); 2503 /* just for safety */ 2504 if (maxlen < sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) + 2505 ((sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7)) { 2506 goto fail; 2507 } 2508 2509 { 2510 /* get ip6 linklocal address for ifp(my outgoing interface). */ 2511 struct in6_ifaddr *ia; 2512 if ((ia = in6ifa_ifpforlinklocal(ifp, 2513 IN6_IFF_NOTREADY| 2514 IN6_IFF_ANYCAST)) == NULL) 2515 goto fail; 2516 ifp_ll6 = &ia->ia_addr.sin6_addr; 2517 } 2518 2519 /* get ip6 linklocal address for the router. */ 2520 if (rt->rt_gateway && (rt->rt_flags & RTF_GATEWAY)) { 2521 struct sockaddr_in6 *sin6; 2522 sin6 = (struct sockaddr_in6 *)rt->rt_gateway; 2523 router_ll6 = &sin6->sin6_addr; 2524 if (!IN6_IS_ADDR_LINKLOCAL(router_ll6)) 2525 router_ll6 = (struct in6_addr *)NULL; 2526 } else 2527 router_ll6 = (struct in6_addr *)NULL; 2528 2529 /* ip6 */ 2530 ip6 = mtod(m, struct ip6_hdr *); 2531 ip6->ip6_flow = 0; 2532 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2533 ip6->ip6_vfc |= IPV6_VERSION; 2534 /* ip6->ip6_plen will be set later */ 2535 ip6->ip6_nxt = IPPROTO_ICMPV6; 2536 ip6->ip6_hlim = 255; 2537 /* ip6->ip6_src must be linklocal addr for my outgoing if. */ 2538 bcopy(ifp_ll6, &ip6->ip6_src, sizeof(struct in6_addr)); 2539 bcopy(&sip6->ip6_src, &ip6->ip6_dst, sizeof(struct in6_addr)); 2540 2541 /* ND Redirect */ 2542 nd_rd = (struct nd_redirect *)(ip6 + 1); 2543 nd_rd->nd_rd_type = ND_REDIRECT; 2544 nd_rd->nd_rd_code = 0; 2545 nd_rd->nd_rd_reserved = 0; 2546 if (rt->rt_flags & RTF_GATEWAY) { 2547 /* 2548 * nd_rd->nd_rd_target must be a link-local address in 2549 * better router cases. 2550 */ 2551 if (!router_ll6) 2552 goto fail; 2553 bcopy(router_ll6, &nd_rd->nd_rd_target, 2554 sizeof(nd_rd->nd_rd_target)); 2555 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2556 sizeof(nd_rd->nd_rd_dst)); 2557 } else { 2558 /* make sure redtgt == reddst */ 2559 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_target, 2560 sizeof(nd_rd->nd_rd_target)); 2561 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2562 sizeof(nd_rd->nd_rd_dst)); 2563 } 2564 2565 p = (u_char *)(nd_rd + 1); 2566 2567 if (!router_ll6) 2568 goto nolladdropt; 2569 2570 { 2571 /* target lladdr option */ 2572 struct rtentry *rt_router = NULL; 2573 int len; 2574 struct sockaddr_dl *sdl; 2575 struct nd_opt_hdr *nd_opt; 2576 char *lladdr; 2577 2578 rt_router = nd6_lookup(router_ll6, 0, ifp); 2579 if (!rt_router) 2580 goto nolladdropt; 2581 len = sizeof(*nd_opt) + ifp->if_addrlen; 2582 len = (len + 7) & ~7; /* round by 8 */ 2583 /* safety check */ 2584 if (len + (p - (u_char *)ip6) > maxlen) 2585 goto nolladdropt; 2586 if (!(rt_router->rt_flags & RTF_GATEWAY) && 2587 (rt_router->rt_flags & RTF_LLINFO) && 2588 (rt_router->rt_gateway->sa_family == AF_LINK) && 2589 (sdl = (struct sockaddr_dl *)rt_router->rt_gateway) && 2590 sdl->sdl_alen) { 2591 nd_opt = (struct nd_opt_hdr *)p; 2592 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 2593 nd_opt->nd_opt_len = len >> 3; 2594 lladdr = (char *)(nd_opt + 1); 2595 bcopy(LLADDR(sdl), lladdr, ifp->if_addrlen); 2596 p += len; 2597 } 2598 } 2599 nolladdropt:; 2600 2601 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2602 2603 /* just to be safe */ 2604 #ifdef M_DECRYPTED /*not openbsd*/ 2605 if (m0->m_flags & M_DECRYPTED) 2606 goto noredhdropt; 2607 #endif 2608 if (p - (u_char *)ip6 > maxlen) 2609 goto noredhdropt; 2610 2611 { 2612 /* redirected header option */ 2613 int len; 2614 struct nd_opt_rd_hdr *nd_opt_rh; 2615 2616 /* 2617 * compute the maximum size for icmp6 redirect header option. 2618 * XXX room for auth header? 2619 */ 2620 len = maxlen - (p - (u_char *)ip6); 2621 len &= ~7; 2622 2623 /* This is just for simplicity. */ 2624 if (m0->m_pkthdr.len != m0->m_len) { 2625 if (m0->m_next) { 2626 m_freem(m0->m_next); 2627 m0->m_next = NULL; 2628 } 2629 m0->m_pkthdr.len = m0->m_len; 2630 } 2631 2632 /* 2633 * Redirected header option spec (RFC2461 4.6.3) talks nothing 2634 * about padding/truncate rule for the original IP packet. 2635 * From the discussion on IPv6imp in Feb 1999, 2636 * the consensus was: 2637 * - "attach as much as possible" is the goal 2638 * - pad if not aligned (original size can be guessed by 2639 * original ip6 header) 2640 * Following code adds the padding if it is simple enough, 2641 * and truncates if not. 2642 */ 2643 if (m0->m_next || m0->m_pkthdr.len != m0->m_len) 2644 panic("assumption failed in %s:%d", __FILE__, 2645 __LINE__); 2646 2647 if (len - sizeof(*nd_opt_rh) < m0->m_pkthdr.len) { 2648 /* not enough room, truncate */ 2649 m0->m_pkthdr.len = m0->m_len = len - 2650 sizeof(*nd_opt_rh); 2651 } else { 2652 /* enough room, pad or truncate */ 2653 size_t extra; 2654 2655 extra = m0->m_pkthdr.len % 8; 2656 if (extra) { 2657 /* pad if easy enough, truncate if not */ 2658 if (8 - extra <= M_TRAILINGSPACE(m0)) { 2659 /* pad */ 2660 m0->m_len += (8 - extra); 2661 m0->m_pkthdr.len += (8 - extra); 2662 } else { 2663 /* truncate */ 2664 m0->m_pkthdr.len -= extra; 2665 m0->m_len -= extra; 2666 } 2667 } 2668 len = m0->m_pkthdr.len + sizeof(*nd_opt_rh); 2669 m0->m_pkthdr.len = m0->m_len = len - 2670 sizeof(*nd_opt_rh); 2671 } 2672 2673 nd_opt_rh = (struct nd_opt_rd_hdr *)p; 2674 bzero(nd_opt_rh, sizeof(*nd_opt_rh)); 2675 nd_opt_rh->nd_opt_rh_type = ND_OPT_REDIRECTED_HEADER; 2676 nd_opt_rh->nd_opt_rh_len = len >> 3; 2677 p += sizeof(*nd_opt_rh); 2678 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2679 2680 /* connect m0 to m */ 2681 m_tag_delete_chain(m0, NULL); 2682 m0->m_flags &= ~M_PKTHDR; 2683 m->m_next = m0; 2684 m->m_pkthdr.len = m->m_len + m0->m_len; 2685 m0 = NULL; 2686 } 2687 noredhdropt:; 2688 if (m0) { 2689 m_freem(m0); 2690 m0 = NULL; 2691 } 2692 2693 /* XXX: clear embedded link IDs in the inner header */ 2694 in6_clearscope(&sip6->ip6_src); 2695 in6_clearscope(&sip6->ip6_dst); 2696 in6_clearscope(&nd_rd->nd_rd_target); 2697 in6_clearscope(&nd_rd->nd_rd_dst); 2698 2699 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr)); 2700 2701 nd_rd->nd_rd_cksum = 0; 2702 nd_rd->nd_rd_cksum = in6_cksum(m, IPPROTO_ICMPV6, 2703 sizeof(*ip6), ntohs(ip6->ip6_plen)); 2704 2705 /* send the packet to outside... */ 2706 ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL); 2707 if (outif) { 2708 icmp6_ifstat_inc(outif, ifs6_out_msg); 2709 icmp6_ifstat_inc(outif, ifs6_out_redirect); 2710 } 2711 V_icmp6stat.icp6s_outhist[ND_REDIRECT]++; 2712 2713 return; 2714 2715 fail: 2716 if (m) 2717 m_freem(m); 2718 if (m0) 2719 m_freem(m0); 2720 } 2721 2722 /* 2723 * ICMPv6 socket option processing. 2724 */ 2725 int 2726 icmp6_ctloutput(struct socket *so, struct sockopt *sopt) 2727 { 2728 int error = 0; 2729 int optlen; 2730 struct inpcb *inp = sotoinpcb(so); 2731 int level, op, optname; 2732 2733 if (sopt) { 2734 level = sopt->sopt_level; 2735 op = sopt->sopt_dir; 2736 optname = sopt->sopt_name; 2737 optlen = sopt->sopt_valsize; 2738 } else 2739 level = op = optname = optlen = 0; 2740 2741 if (level != IPPROTO_ICMPV6) { 2742 return EINVAL; 2743 } 2744 2745 switch (op) { 2746 case PRCO_SETOPT: 2747 switch (optname) { 2748 case ICMP6_FILTER: 2749 { 2750 struct icmp6_filter ic6f; 2751 2752 if (optlen != sizeof(ic6f)) { 2753 error = EMSGSIZE; 2754 break; 2755 } 2756 error = sooptcopyin(sopt, &ic6f, optlen, optlen); 2757 if (error == 0) { 2758 INP_WLOCK(inp); 2759 *inp->in6p_icmp6filt = ic6f; 2760 INP_WUNLOCK(inp); 2761 } 2762 break; 2763 } 2764 2765 default: 2766 error = ENOPROTOOPT; 2767 break; 2768 } 2769 break; 2770 2771 case PRCO_GETOPT: 2772 switch (optname) { 2773 case ICMP6_FILTER: 2774 { 2775 struct icmp6_filter ic6f; 2776 2777 INP_RLOCK(inp); 2778 ic6f = *inp->in6p_icmp6filt; 2779 INP_RUNLOCK(inp); 2780 error = sooptcopyout(sopt, &ic6f, sizeof(ic6f)); 2781 break; 2782 } 2783 2784 default: 2785 error = ENOPROTOOPT; 2786 break; 2787 } 2788 break; 2789 } 2790 2791 return (error); 2792 } 2793 2794 /* 2795 * Perform rate limit check. 2796 * Returns 0 if it is okay to send the icmp6 packet. 2797 * Returns 1 if the router SHOULD NOT send this icmp6 packet due to rate 2798 * limitation. 2799 * 2800 * XXX per-destination/type check necessary? 2801 * 2802 * dst - not used at this moment 2803 * type - not used at this moment 2804 * code - not used at this moment 2805 */ 2806 static int 2807 icmp6_ratelimit(const struct in6_addr *dst, const int type, 2808 const int code) 2809 { 2810 INIT_VNET_INET6(curvnet); 2811 int ret; 2812 2813 ret = 0; /* okay to send */ 2814 2815 /* PPS limit */ 2816 if (!ppsratecheck(&V_icmp6errppslim_last, &V_icmp6errpps_count, 2817 V_icmp6errppslim)) { 2818 /* The packet is subject to rate limit */ 2819 ret++; 2820 } 2821 2822 return ret; 2823 } 2824