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/jail.h> 73 #include <sys/kernel.h> 74 #include <sys/lock.h> 75 #include <sys/malloc.h> 76 #include <sys/mbuf.h> 77 #include <sys/proc.h> 78 #include <sys/protosw.h> 79 #include <sys/signalvar.h> 80 #include <sys/socket.h> 81 #include <sys/socketvar.h> 82 #include <sys/sx.h> 83 #include <sys/syslog.h> 84 #include <sys/systm.h> 85 #include <sys/time.h> 86 87 #include <net/if.h> 88 #include <net/if_dl.h> 89 #include <net/if_llatbl.h> 90 #include <net/if_types.h> 91 #include <net/route.h> 92 #include <net/vnet.h> 93 94 #include <netinet/in.h> 95 #include <netinet/in_pcb.h> 96 #include <netinet/in_var.h> 97 #include <netinet/ip6.h> 98 #include <netinet/icmp6.h> 99 #include <netinet/tcp_var.h> 100 101 #include <netinet6/in6_ifattach.h> 102 #include <netinet6/in6_pcb.h> 103 #include <netinet6/ip6protosw.h> 104 #include <netinet6/ip6_var.h> 105 #include <netinet6/scope6_var.h> 106 #include <netinet6/mld6_var.h> 107 #include <netinet6/nd6.h> 108 #include <netinet6/send.h> 109 110 #ifdef IPSEC 111 #include <netipsec/ipsec.h> 112 #include <netipsec/key.h> 113 #endif 114 115 extern struct domain inet6domain; 116 117 VNET_DEFINE(struct icmp6stat, icmp6stat); 118 119 VNET_DECLARE(struct inpcbinfo, ripcbinfo); 120 VNET_DECLARE(struct inpcbhead, ripcb); 121 VNET_DECLARE(int, icmp6errppslim); 122 static VNET_DEFINE(int, icmp6errpps_count) = 0; 123 static VNET_DEFINE(struct timeval, icmp6errppslim_last); 124 VNET_DECLARE(int, icmp6_nodeinfo); 125 126 #define V_ripcbinfo VNET(ripcbinfo) 127 #define V_ripcb VNET(ripcb) 128 #define V_icmp6errppslim VNET(icmp6errppslim) 129 #define V_icmp6errpps_count VNET(icmp6errpps_count) 130 #define V_icmp6errppslim_last VNET(icmp6errppslim_last) 131 #define V_icmp6_nodeinfo VNET(icmp6_nodeinfo) 132 133 static void icmp6_errcount(struct icmp6errstat *, int, int); 134 static int icmp6_rip6_input(struct mbuf **, int); 135 static int icmp6_ratelimit(const struct in6_addr *, const int, const int); 136 static const char *icmp6_redirect_diag(struct in6_addr *, 137 struct in6_addr *, struct in6_addr *); 138 static struct mbuf *ni6_input(struct mbuf *, int); 139 static struct mbuf *ni6_nametodns(const char *, int, int); 140 static int ni6_dnsmatch(const char *, int, const char *, int); 141 static int ni6_addrs(struct icmp6_nodeinfo *, struct mbuf *, 142 struct ifnet **, struct in6_addr *); 143 static int ni6_store_addrs(struct icmp6_nodeinfo *, struct icmp6_nodeinfo *, 144 struct ifnet *, int); 145 static int icmp6_notify_error(struct mbuf **, int, int, int); 146 147 /* 148 * Kernel module interface for updating icmp6stat. The argument is an index 149 * into icmp6stat treated as an array of u_quad_t. While this encodes the 150 * general layout of icmp6stat into the caller, it doesn't encode its 151 * location, so that future changes to add, for example, per-CPU stats 152 * support won't cause binary compatibility problems for kernel modules. 153 */ 154 void 155 kmod_icmp6stat_inc(int statnum) 156 { 157 158 (*((u_quad_t *)&V_icmp6stat + statnum))++; 159 } 160 161 static void 162 icmp6_errcount(struct icmp6errstat *stat, int type, int code) 163 { 164 switch (type) { 165 case ICMP6_DST_UNREACH: 166 switch (code) { 167 case ICMP6_DST_UNREACH_NOROUTE: 168 stat->icp6errs_dst_unreach_noroute++; 169 return; 170 case ICMP6_DST_UNREACH_ADMIN: 171 stat->icp6errs_dst_unreach_admin++; 172 return; 173 case ICMP6_DST_UNREACH_BEYONDSCOPE: 174 stat->icp6errs_dst_unreach_beyondscope++; 175 return; 176 case ICMP6_DST_UNREACH_ADDR: 177 stat->icp6errs_dst_unreach_addr++; 178 return; 179 case ICMP6_DST_UNREACH_NOPORT: 180 stat->icp6errs_dst_unreach_noport++; 181 return; 182 } 183 break; 184 case ICMP6_PACKET_TOO_BIG: 185 stat->icp6errs_packet_too_big++; 186 return; 187 case ICMP6_TIME_EXCEEDED: 188 switch (code) { 189 case ICMP6_TIME_EXCEED_TRANSIT: 190 stat->icp6errs_time_exceed_transit++; 191 return; 192 case ICMP6_TIME_EXCEED_REASSEMBLY: 193 stat->icp6errs_time_exceed_reassembly++; 194 return; 195 } 196 break; 197 case ICMP6_PARAM_PROB: 198 switch (code) { 199 case ICMP6_PARAMPROB_HEADER: 200 stat->icp6errs_paramprob_header++; 201 return; 202 case ICMP6_PARAMPROB_NEXTHEADER: 203 stat->icp6errs_paramprob_nextheader++; 204 return; 205 case ICMP6_PARAMPROB_OPTION: 206 stat->icp6errs_paramprob_option++; 207 return; 208 } 209 break; 210 case ND_REDIRECT: 211 stat->icp6errs_redirect++; 212 return; 213 } 214 stat->icp6errs_unknown++; 215 } 216 217 /* 218 * A wrapper function for icmp6_error() necessary when the erroneous packet 219 * may not contain enough scope zone information. 220 */ 221 void 222 icmp6_error2(struct mbuf *m, int type, int code, int param, 223 struct ifnet *ifp) 224 { 225 struct ip6_hdr *ip6; 226 227 if (ifp == NULL) 228 return; 229 230 #ifndef PULLDOWN_TEST 231 IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), ); 232 #else 233 if (m->m_len < sizeof(struct ip6_hdr)) { 234 m = m_pullup(m, sizeof(struct ip6_hdr)); 235 if (m == NULL) 236 return; 237 } 238 #endif 239 240 ip6 = mtod(m, struct ip6_hdr *); 241 242 if (in6_setscope(&ip6->ip6_src, ifp, NULL) != 0) 243 return; 244 if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0) 245 return; 246 247 icmp6_error(m, type, code, param); 248 } 249 250 /* 251 * Generate an error packet of type error in response to bad IP6 packet. 252 */ 253 void 254 icmp6_error(struct mbuf *m, int type, int code, int param) 255 { 256 struct ip6_hdr *oip6, *nip6; 257 struct icmp6_hdr *icmp6; 258 u_int preplen; 259 int off; 260 int nxt; 261 262 ICMP6STAT_INC(icp6s_error); 263 264 /* count per-type-code statistics */ 265 icmp6_errcount(&V_icmp6stat.icp6s_outerrhist, type, code); 266 267 #ifdef M_DECRYPTED /*not openbsd*/ 268 if (m->m_flags & M_DECRYPTED) { 269 ICMP6STAT_INC(icp6s_canterror); 270 goto freeit; 271 } 272 #endif 273 274 #ifndef PULLDOWN_TEST 275 IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), ); 276 #else 277 if (m->m_len < sizeof(struct ip6_hdr)) { 278 m = m_pullup(m, sizeof(struct ip6_hdr)); 279 if (m == NULL) 280 return; 281 } 282 #endif 283 oip6 = mtod(m, struct ip6_hdr *); 284 285 /* 286 * If the destination address of the erroneous packet is a multicast 287 * address, or the packet was sent using link-layer multicast, 288 * we should basically suppress sending an error (RFC 2463, Section 289 * 2.4). 290 * We have two exceptions (the item e.2 in that section): 291 * - the Packet Too Big message can be sent for path MTU discovery. 292 * - the Parameter Problem Message that can be allowed an icmp6 error 293 * in the option type field. This check has been done in 294 * ip6_unknown_opt(), so we can just check the type and code. 295 */ 296 if ((m->m_flags & (M_BCAST|M_MCAST) || 297 IN6_IS_ADDR_MULTICAST(&oip6->ip6_dst)) && 298 (type != ICMP6_PACKET_TOO_BIG && 299 (type != ICMP6_PARAM_PROB || 300 code != ICMP6_PARAMPROB_OPTION))) 301 goto freeit; 302 303 /* 304 * RFC 2463, 2.4 (e.5): source address check. 305 * XXX: the case of anycast source? 306 */ 307 if (IN6_IS_ADDR_UNSPECIFIED(&oip6->ip6_src) || 308 IN6_IS_ADDR_MULTICAST(&oip6->ip6_src)) 309 goto freeit; 310 311 /* 312 * If we are about to send ICMPv6 against ICMPv6 error/redirect, 313 * don't do it. 314 */ 315 nxt = -1; 316 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); 317 if (off >= 0 && nxt == IPPROTO_ICMPV6) { 318 struct icmp6_hdr *icp; 319 320 #ifndef PULLDOWN_TEST 321 IP6_EXTHDR_CHECK(m, 0, off + sizeof(struct icmp6_hdr), ); 322 icp = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 323 #else 324 IP6_EXTHDR_GET(icp, struct icmp6_hdr *, m, off, 325 sizeof(*icp)); 326 if (icp == NULL) { 327 ICMP6STAT_INC(icp6s_tooshort); 328 return; 329 } 330 #endif 331 if (icp->icmp6_type < ICMP6_ECHO_REQUEST || 332 icp->icmp6_type == ND_REDIRECT) { 333 /* 334 * ICMPv6 error 335 * Special case: for redirect (which is 336 * informational) we must not send icmp6 error. 337 */ 338 ICMP6STAT_INC(icp6s_canterror); 339 goto freeit; 340 } else { 341 /* ICMPv6 informational - send the error */ 342 } 343 } else { 344 /* non-ICMPv6 - send the error */ 345 } 346 347 oip6 = mtod(m, struct ip6_hdr *); /* adjust pointer */ 348 349 /* Finally, do rate limitation check. */ 350 if (icmp6_ratelimit(&oip6->ip6_src, type, code)) { 351 ICMP6STAT_INC(icp6s_toofreq); 352 goto freeit; 353 } 354 355 /* 356 * OK, ICMP6 can be generated. 357 */ 358 359 if (m->m_pkthdr.len >= ICMPV6_PLD_MAXLEN) 360 m_adj(m, ICMPV6_PLD_MAXLEN - m->m_pkthdr.len); 361 362 preplen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 363 M_PREPEND(m, preplen, M_NOWAIT); /* FIB is also copied over. */ 364 if (m && m->m_len < preplen) 365 m = m_pullup(m, preplen); 366 if (m == NULL) { 367 nd6log((LOG_DEBUG, "ENOBUFS in icmp6_error %d\n", __LINE__)); 368 return; 369 } 370 371 nip6 = mtod(m, struct ip6_hdr *); 372 nip6->ip6_src = oip6->ip6_src; 373 nip6->ip6_dst = oip6->ip6_dst; 374 375 in6_clearscope(&oip6->ip6_src); 376 in6_clearscope(&oip6->ip6_dst); 377 378 icmp6 = (struct icmp6_hdr *)(nip6 + 1); 379 icmp6->icmp6_type = type; 380 icmp6->icmp6_code = code; 381 icmp6->icmp6_pptr = htonl((u_int32_t)param); 382 383 /* 384 * icmp6_reflect() is designed to be in the input path. 385 * icmp6_error() can be called from both input and output path, 386 * and if we are in output path rcvif could contain bogus value. 387 * clear m->m_pkthdr.rcvif for safety, we should have enough scope 388 * information in ip header (nip6). 389 */ 390 m->m_pkthdr.rcvif = NULL; 391 392 ICMP6STAT_INC(icp6s_outhist[type]); 393 icmp6_reflect(m, sizeof(struct ip6_hdr)); /* header order: IPv6 - ICMPv6 */ 394 395 return; 396 397 freeit: 398 /* 399 * If we can't tell whether or not we can generate ICMP6, free it. 400 */ 401 m_freem(m); 402 } 403 404 /* 405 * Process a received ICMP6 message. 406 */ 407 int 408 icmp6_input(struct mbuf **mp, int *offp, int proto) 409 { 410 struct mbuf *m = *mp, *n; 411 struct ifnet *ifp; 412 struct ip6_hdr *ip6, *nip6; 413 struct icmp6_hdr *icmp6, *nicmp6; 414 int off = *offp; 415 int icmp6len = m->m_pkthdr.len - *offp; 416 int code, sum, noff; 417 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 418 int ip6len, error; 419 420 ifp = m->m_pkthdr.rcvif; 421 422 #ifndef PULLDOWN_TEST 423 IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_hdr), IPPROTO_DONE); 424 /* m might change if M_LOOP. So, call mtod after this */ 425 #endif 426 427 /* 428 * Locate icmp6 structure in mbuf, and check 429 * that not corrupted and of at least minimum length 430 */ 431 432 ip6 = mtod(m, struct ip6_hdr *); 433 ip6len = sizeof(struct ip6_hdr) + ntohs(ip6->ip6_plen); 434 if (icmp6len < sizeof(struct icmp6_hdr)) { 435 ICMP6STAT_INC(icp6s_tooshort); 436 goto freeit; 437 } 438 439 /* 440 * Check multicast group membership. 441 * Note: SSM filters are not applied for ICMPv6 traffic. 442 */ 443 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 444 struct in6_multi *inm; 445 446 inm = in6m_lookup(ifp, &ip6->ip6_dst); 447 if (inm == NULL) { 448 IP6STAT_INC(ip6s_notmember); 449 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 450 goto freeit; 451 } 452 } 453 454 /* 455 * calculate the checksum 456 */ 457 #ifndef PULLDOWN_TEST 458 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off); 459 #else 460 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 461 if (icmp6 == NULL) { 462 ICMP6STAT_INC(icp6s_tooshort); 463 return IPPROTO_DONE; 464 } 465 #endif 466 code = icmp6->icmp6_code; 467 468 if ((sum = in6_cksum(m, IPPROTO_ICMPV6, off, icmp6len)) != 0) { 469 nd6log((LOG_ERR, 470 "ICMP6 checksum error(%d|%x) %s\n", 471 icmp6->icmp6_type, sum, 472 ip6_sprintf(ip6bufs, &ip6->ip6_src))); 473 ICMP6STAT_INC(icp6s_checksum); 474 goto freeit; 475 } 476 477 if (faithprefix_p != NULL && (*faithprefix_p)(&ip6->ip6_dst)) { 478 /* 479 * Deliver very specific ICMP6 type only. 480 * This is important to deliver TOOBIG. Otherwise PMTUD 481 * will not work. 482 */ 483 switch (icmp6->icmp6_type) { 484 case ICMP6_DST_UNREACH: 485 case ICMP6_PACKET_TOO_BIG: 486 case ICMP6_TIME_EXCEEDED: 487 break; 488 default: 489 goto freeit; 490 } 491 } 492 493 ICMP6STAT_INC(icp6s_inhist[icmp6->icmp6_type]); 494 icmp6_ifstat_inc(ifp, ifs6_in_msg); 495 if (icmp6->icmp6_type < ICMP6_INFOMSG_MASK) 496 icmp6_ifstat_inc(ifp, ifs6_in_error); 497 498 switch (icmp6->icmp6_type) { 499 case ICMP6_DST_UNREACH: 500 icmp6_ifstat_inc(ifp, ifs6_in_dstunreach); 501 switch (code) { 502 case ICMP6_DST_UNREACH_NOROUTE: 503 code = PRC_UNREACH_NET; 504 break; 505 case ICMP6_DST_UNREACH_ADMIN: 506 icmp6_ifstat_inc(ifp, ifs6_in_adminprohib); 507 code = PRC_UNREACH_PROTOCOL; /* is this a good code? */ 508 break; 509 case ICMP6_DST_UNREACH_ADDR: 510 code = PRC_HOSTDEAD; 511 break; 512 case ICMP6_DST_UNREACH_BEYONDSCOPE: 513 /* I mean "source address was incorrect." */ 514 code = PRC_PARAMPROB; 515 break; 516 case ICMP6_DST_UNREACH_NOPORT: 517 code = PRC_UNREACH_PORT; 518 break; 519 default: 520 goto badcode; 521 } 522 goto deliver; 523 break; 524 525 case ICMP6_PACKET_TOO_BIG: 526 icmp6_ifstat_inc(ifp, ifs6_in_pkttoobig); 527 528 /* validation is made in icmp6_mtudisc_update */ 529 530 code = PRC_MSGSIZE; 531 532 /* 533 * Updating the path MTU will be done after examining 534 * intermediate extension headers. 535 */ 536 goto deliver; 537 break; 538 539 case ICMP6_TIME_EXCEEDED: 540 icmp6_ifstat_inc(ifp, ifs6_in_timeexceed); 541 switch (code) { 542 case ICMP6_TIME_EXCEED_TRANSIT: 543 code = PRC_TIMXCEED_INTRANS; 544 break; 545 case ICMP6_TIME_EXCEED_REASSEMBLY: 546 code = PRC_TIMXCEED_REASS; 547 break; 548 default: 549 goto badcode; 550 } 551 goto deliver; 552 break; 553 554 case ICMP6_PARAM_PROB: 555 icmp6_ifstat_inc(ifp, ifs6_in_paramprob); 556 switch (code) { 557 case ICMP6_PARAMPROB_NEXTHEADER: 558 code = PRC_UNREACH_PROTOCOL; 559 break; 560 case ICMP6_PARAMPROB_HEADER: 561 case ICMP6_PARAMPROB_OPTION: 562 code = PRC_PARAMPROB; 563 break; 564 default: 565 goto badcode; 566 } 567 goto deliver; 568 break; 569 570 case ICMP6_ECHO_REQUEST: 571 icmp6_ifstat_inc(ifp, ifs6_in_echo); 572 if (code != 0) 573 goto badcode; 574 if ((n = m_copy(m, 0, M_COPYALL)) == NULL) { 575 /* Give up remote */ 576 break; 577 } 578 if ((n->m_flags & M_EXT) != 0 579 || n->m_len < off + sizeof(struct icmp6_hdr)) { 580 struct mbuf *n0 = n; 581 int n0len; 582 583 CTASSERT(sizeof(*nip6) + sizeof(*nicmp6) <= MHLEN); 584 n = m_gethdr(M_NOWAIT, n0->m_type); 585 if (n == NULL) { 586 /* Give up remote */ 587 m_freem(n0); 588 break; 589 } 590 591 m_move_pkthdr(n, n0); /* FIB copied. */ 592 n0len = n0->m_pkthdr.len; /* save for use below */ 593 /* 594 * Copy IPv6 and ICMPv6 only. 595 */ 596 nip6 = mtod(n, struct ip6_hdr *); 597 bcopy(ip6, nip6, sizeof(struct ip6_hdr)); 598 nicmp6 = (struct icmp6_hdr *)(nip6 + 1); 599 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr)); 600 noff = sizeof(struct ip6_hdr); 601 /* new mbuf contains only ipv6+icmpv6 headers */ 602 n->m_len = noff + sizeof(struct icmp6_hdr); 603 /* 604 * Adjust mbuf. ip6_plen will be adjusted in 605 * ip6_output(). 606 */ 607 m_adj(n0, off + sizeof(struct icmp6_hdr)); 608 /* recalculate complete packet size */ 609 n->m_pkthdr.len = n0len + (noff - off); 610 n->m_next = n0; 611 } else { 612 nip6 = mtod(n, struct ip6_hdr *); 613 IP6_EXTHDR_GET(nicmp6, struct icmp6_hdr *, n, off, 614 sizeof(*nicmp6)); 615 noff = off; 616 } 617 nicmp6->icmp6_type = ICMP6_ECHO_REPLY; 618 nicmp6->icmp6_code = 0; 619 if (n) { 620 ICMP6STAT_INC(icp6s_reflect); 621 ICMP6STAT_INC(icp6s_outhist[ICMP6_ECHO_REPLY]); 622 icmp6_reflect(n, noff); 623 } 624 break; 625 626 case ICMP6_ECHO_REPLY: 627 icmp6_ifstat_inc(ifp, ifs6_in_echoreply); 628 if (code != 0) 629 goto badcode; 630 break; 631 632 case MLD_LISTENER_QUERY: 633 case MLD_LISTENER_REPORT: 634 case MLD_LISTENER_DONE: 635 case MLDV2_LISTENER_REPORT: 636 /* 637 * Drop MLD traffic which is not link-local, has a hop limit 638 * of greater than 1 hop, or which does not have the 639 * IPv6 HBH Router Alert option. 640 * As IPv6 HBH options are stripped in ip6_input() we must 641 * check an mbuf header flag. 642 * XXX Should we also sanity check that these messages 643 * were directed to a link-local multicast prefix? 644 */ 645 if ((ip6->ip6_hlim != 1) || (m->m_flags & M_RTALERT_MLD) == 0) 646 goto freeit; 647 if (mld_input(m, off, icmp6len) != 0) 648 return (IPPROTO_DONE); 649 /* m stays. */ 650 break; 651 652 case ICMP6_WRUREQUEST: /* ICMP6_FQDN_QUERY */ 653 { 654 enum { WRU, FQDN } mode; 655 656 if (!V_icmp6_nodeinfo) 657 break; 658 659 if (icmp6len == sizeof(struct icmp6_hdr) + 4) 660 mode = WRU; 661 else if (icmp6len >= sizeof(struct icmp6_nodeinfo)) 662 mode = FQDN; 663 else 664 goto badlen; 665 666 if (mode == FQDN) { 667 #ifndef PULLDOWN_TEST 668 IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_nodeinfo), 669 IPPROTO_DONE); 670 #endif 671 n = m_copy(m, 0, M_COPYALL); 672 if (n) 673 n = ni6_input(n, off); 674 /* XXX meaningless if n == NULL */ 675 noff = sizeof(struct ip6_hdr); 676 } else { 677 struct prison *pr; 678 u_char *p; 679 int maxhlen, hlen; 680 681 /* 682 * XXX: this combination of flags is pointless, 683 * but should we keep this for compatibility? 684 */ 685 if ((V_icmp6_nodeinfo & 5) != 5) 686 break; 687 688 if (code != 0) 689 goto badcode; 690 691 CTASSERT(sizeof(*nip6) + sizeof(*nicmp6) + 4 <= MHLEN); 692 n = m_gethdr(M_NOWAIT, m->m_type); 693 if (n == NULL) { 694 /* Give up remote */ 695 break; 696 } 697 if (!m_dup_pkthdr(n, m, M_NOWAIT)) { 698 /* 699 * Previous code did a blind M_COPY_PKTHDR 700 * and said "just for rcvif". If true, then 701 * we could tolerate the dup failing (due to 702 * the deep copy of the tag chain). For now 703 * be conservative and just fail. 704 */ 705 m_free(n); 706 n = NULL; 707 } 708 maxhlen = M_TRAILINGSPACE(n) - 709 (sizeof(*nip6) + sizeof(*nicmp6) + 4); 710 pr = curthread->td_ucred->cr_prison; 711 mtx_lock(&pr->pr_mtx); 712 hlen = strlen(pr->pr_hostname); 713 if (maxhlen > hlen) 714 maxhlen = hlen; 715 /* 716 * Copy IPv6 and ICMPv6 only. 717 */ 718 nip6 = mtod(n, struct ip6_hdr *); 719 bcopy(ip6, nip6, sizeof(struct ip6_hdr)); 720 nicmp6 = (struct icmp6_hdr *)(nip6 + 1); 721 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr)); 722 p = (u_char *)(nicmp6 + 1); 723 bzero(p, 4); 724 /* meaningless TTL */ 725 bcopy(pr->pr_hostname, p + 4, maxhlen); 726 mtx_unlock(&pr->pr_mtx); 727 noff = sizeof(struct ip6_hdr); 728 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) + 729 sizeof(struct icmp6_hdr) + 4 + maxhlen; 730 nicmp6->icmp6_type = ICMP6_WRUREPLY; 731 nicmp6->icmp6_code = 0; 732 } 733 if (n) { 734 ICMP6STAT_INC(icp6s_reflect); 735 ICMP6STAT_INC(icp6s_outhist[ICMP6_WRUREPLY]); 736 icmp6_reflect(n, noff); 737 } 738 break; 739 } 740 741 case ICMP6_WRUREPLY: 742 if (code != 0) 743 goto badcode; 744 break; 745 746 case ND_ROUTER_SOLICIT: 747 icmp6_ifstat_inc(ifp, ifs6_in_routersolicit); 748 if (code != 0) 749 goto badcode; 750 if (icmp6len < sizeof(struct nd_router_solicit)) 751 goto badlen; 752 if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) == NULL) { 753 /* give up local */ 754 755 /* Send incoming SeND packet to user space. */ 756 if (send_sendso_input_hook != NULL) { 757 IP6_EXTHDR_CHECK(m, off, 758 icmp6len, IPPROTO_DONE); 759 error = send_sendso_input_hook(m, ifp, 760 SND_IN, ip6len); 761 /* -1 == no app on SEND socket */ 762 if (error == 0) 763 return (IPPROTO_DONE); 764 nd6_rs_input(m, off, icmp6len); 765 } else 766 nd6_rs_input(m, off, icmp6len); 767 m = NULL; 768 goto freeit; 769 } 770 if (send_sendso_input_hook != NULL) { 771 IP6_EXTHDR_CHECK(n, off, 772 icmp6len, IPPROTO_DONE); 773 error = send_sendso_input_hook(n, ifp, 774 SND_IN, ip6len); 775 if (error == 0) 776 goto freeit; 777 /* -1 == no app on SEND socket */ 778 nd6_rs_input(n, off, icmp6len); 779 } else 780 nd6_rs_input(n, off, icmp6len); 781 /* m stays. */ 782 break; 783 784 case ND_ROUTER_ADVERT: 785 icmp6_ifstat_inc(ifp, ifs6_in_routeradvert); 786 if (code != 0) 787 goto badcode; 788 if (icmp6len < sizeof(struct nd_router_advert)) 789 goto badlen; 790 if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) == NULL) { 791 792 /* Send incoming SeND-protected/ND packet to user space. */ 793 if (send_sendso_input_hook != NULL) { 794 error = send_sendso_input_hook(m, ifp, 795 SND_IN, ip6len); 796 if (error == 0) 797 return (IPPROTO_DONE); 798 nd6_ra_input(m, off, icmp6len); 799 } else 800 nd6_ra_input(m, off, icmp6len); 801 m = NULL; 802 goto freeit; 803 } 804 if (send_sendso_input_hook != NULL) { 805 error = send_sendso_input_hook(n, ifp, 806 SND_IN, ip6len); 807 if (error == 0) 808 goto freeit; 809 nd6_ra_input(n, off, icmp6len); 810 } else 811 nd6_ra_input(n, off, icmp6len); 812 /* m stays. */ 813 break; 814 815 case ND_NEIGHBOR_SOLICIT: 816 icmp6_ifstat_inc(ifp, ifs6_in_neighborsolicit); 817 if (code != 0) 818 goto badcode; 819 if (icmp6len < sizeof(struct nd_neighbor_solicit)) 820 goto badlen; 821 if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) == NULL) { 822 if (send_sendso_input_hook != NULL) { 823 error = send_sendso_input_hook(m, ifp, 824 SND_IN, ip6len); 825 if (error == 0) 826 return (IPPROTO_DONE); 827 nd6_ns_input(m, off, icmp6len); 828 } else 829 nd6_ns_input(m, off, icmp6len); 830 m = NULL; 831 goto freeit; 832 } 833 if (send_sendso_input_hook != NULL) { 834 error = send_sendso_input_hook(n, ifp, 835 SND_IN, ip6len); 836 if (error == 0) 837 goto freeit; 838 nd6_ns_input(n, off, icmp6len); 839 } else 840 nd6_ns_input(n, off, icmp6len); 841 /* m stays. */ 842 break; 843 844 case ND_NEIGHBOR_ADVERT: 845 icmp6_ifstat_inc(ifp, ifs6_in_neighboradvert); 846 if (code != 0) 847 goto badcode; 848 if (icmp6len < sizeof(struct nd_neighbor_advert)) 849 goto badlen; 850 if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) == NULL) { 851 852 /* Send incoming SeND-protected/ND packet to user space. */ 853 if (send_sendso_input_hook != NULL) { 854 error = send_sendso_input_hook(m, ifp, 855 SND_IN, ip6len); 856 if (error == 0) 857 return (IPPROTO_DONE); 858 nd6_na_input(m, off, icmp6len); 859 } else 860 nd6_na_input(m, off, icmp6len); 861 m = NULL; 862 goto freeit; 863 } 864 if (send_sendso_input_hook != NULL) { 865 error = send_sendso_input_hook(n, ifp, 866 SND_IN, ip6len); 867 if (error == 0) 868 goto freeit; 869 nd6_na_input(n, off, icmp6len); 870 } else 871 nd6_na_input(n, off, icmp6len); 872 /* m stays. */ 873 break; 874 875 case ND_REDIRECT: 876 icmp6_ifstat_inc(ifp, ifs6_in_redirect); 877 if (code != 0) 878 goto badcode; 879 if (icmp6len < sizeof(struct nd_redirect)) 880 goto badlen; 881 if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) == NULL) { 882 if (send_sendso_input_hook != NULL) { 883 error = send_sendso_input_hook(m, ifp, 884 SND_IN, ip6len); 885 if (error == 0) 886 return (IPPROTO_DONE); 887 icmp6_redirect_input(m, off); 888 } else 889 icmp6_redirect_input(m, off); 890 m = NULL; 891 goto freeit; 892 } 893 if (send_sendso_input_hook != NULL) { 894 error = send_sendso_input_hook(n, ifp, 895 SND_IN, ip6len); 896 if (error == 0) 897 goto freeit; 898 icmp6_redirect_input(n, off); 899 } else 900 icmp6_redirect_input(n, off); 901 /* m stays. */ 902 break; 903 904 case ICMP6_ROUTER_RENUMBERING: 905 if (code != ICMP6_ROUTER_RENUMBERING_COMMAND && 906 code != ICMP6_ROUTER_RENUMBERING_RESULT) 907 goto badcode; 908 if (icmp6len < sizeof(struct icmp6_router_renum)) 909 goto badlen; 910 break; 911 912 default: 913 nd6log((LOG_DEBUG, 914 "icmp6_input: unknown type %d(src=%s, dst=%s, ifid=%d)\n", 915 icmp6->icmp6_type, ip6_sprintf(ip6bufs, &ip6->ip6_src), 916 ip6_sprintf(ip6bufd, &ip6->ip6_dst), 917 ifp ? ifp->if_index : 0)); 918 if (icmp6->icmp6_type < ICMP6_ECHO_REQUEST) { 919 /* ICMPv6 error: MUST deliver it by spec... */ 920 code = PRC_NCMDS; 921 /* deliver */ 922 } else { 923 /* ICMPv6 informational: MUST not deliver */ 924 break; 925 } 926 deliver: 927 if (icmp6_notify_error(&m, off, icmp6len, code) != 0) { 928 /* In this case, m should've been freed. */ 929 return (IPPROTO_DONE); 930 } 931 break; 932 933 badcode: 934 ICMP6STAT_INC(icp6s_badcode); 935 break; 936 937 badlen: 938 ICMP6STAT_INC(icp6s_badlen); 939 break; 940 } 941 942 /* deliver the packet to appropriate sockets */ 943 icmp6_rip6_input(&m, *offp); 944 945 return IPPROTO_DONE; 946 947 freeit: 948 m_freem(m); 949 return IPPROTO_DONE; 950 } 951 952 static int 953 icmp6_notify_error(struct mbuf **mp, int off, int icmp6len, int code) 954 { 955 struct mbuf *m = *mp; 956 struct icmp6_hdr *icmp6; 957 struct ip6_hdr *eip6; 958 u_int32_t notifymtu; 959 struct sockaddr_in6 icmp6src, icmp6dst; 960 961 if (icmp6len < sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr)) { 962 ICMP6STAT_INC(icp6s_tooshort); 963 goto freeit; 964 } 965 #ifndef PULLDOWN_TEST 966 IP6_EXTHDR_CHECK(m, off, 967 sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr), -1); 968 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 969 #else 970 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, 971 sizeof(*icmp6) + sizeof(struct ip6_hdr)); 972 if (icmp6 == NULL) { 973 ICMP6STAT_INC(icp6s_tooshort); 974 return (-1); 975 } 976 #endif 977 eip6 = (struct ip6_hdr *)(icmp6 + 1); 978 979 /* Detect the upper level protocol */ 980 { 981 void (*ctlfunc)(int, struct sockaddr *, void *); 982 u_int8_t nxt = eip6->ip6_nxt; 983 int eoff = off + sizeof(struct icmp6_hdr) + 984 sizeof(struct ip6_hdr); 985 struct ip6ctlparam ip6cp; 986 struct in6_addr *finaldst = NULL; 987 int icmp6type = icmp6->icmp6_type; 988 struct ip6_frag *fh; 989 struct ip6_rthdr *rth; 990 struct ip6_rthdr0 *rth0; 991 int rthlen; 992 993 while (1) { /* XXX: should avoid infinite loop explicitly? */ 994 struct ip6_ext *eh; 995 996 switch (nxt) { 997 case IPPROTO_HOPOPTS: 998 case IPPROTO_DSTOPTS: 999 case IPPROTO_AH: 1000 #ifndef PULLDOWN_TEST 1001 IP6_EXTHDR_CHECK(m, 0, 1002 eoff + sizeof(struct ip6_ext), -1); 1003 eh = (struct ip6_ext *)(mtod(m, caddr_t) + eoff); 1004 #else 1005 IP6_EXTHDR_GET(eh, struct ip6_ext *, m, 1006 eoff, sizeof(*eh)); 1007 if (eh == NULL) { 1008 ICMP6STAT_INC(icp6s_tooshort); 1009 return (-1); 1010 } 1011 #endif 1012 1013 if (nxt == IPPROTO_AH) 1014 eoff += (eh->ip6e_len + 2) << 2; 1015 else 1016 eoff += (eh->ip6e_len + 1) << 3; 1017 nxt = eh->ip6e_nxt; 1018 break; 1019 case IPPROTO_ROUTING: 1020 /* 1021 * When the erroneous packet contains a 1022 * routing header, we should examine the 1023 * header to determine the final destination. 1024 * Otherwise, we can't properly update 1025 * information that depends on the final 1026 * destination (e.g. path MTU). 1027 */ 1028 #ifndef PULLDOWN_TEST 1029 IP6_EXTHDR_CHECK(m, 0, eoff + sizeof(*rth), -1); 1030 rth = (struct ip6_rthdr *) 1031 (mtod(m, caddr_t) + eoff); 1032 #else 1033 IP6_EXTHDR_GET(rth, struct ip6_rthdr *, m, 1034 eoff, sizeof(*rth)); 1035 if (rth == NULL) { 1036 ICMP6STAT_INC(icp6s_tooshort); 1037 return (-1); 1038 } 1039 #endif 1040 rthlen = (rth->ip6r_len + 1) << 3; 1041 /* 1042 * XXX: currently there is no 1043 * officially defined type other 1044 * than type-0. 1045 * Note that if the segment left field 1046 * is 0, all intermediate hops must 1047 * have been passed. 1048 */ 1049 if (rth->ip6r_segleft && 1050 rth->ip6r_type == IPV6_RTHDR_TYPE_0) { 1051 int hops; 1052 1053 #ifndef PULLDOWN_TEST 1054 IP6_EXTHDR_CHECK(m, 0, eoff + rthlen, -1); 1055 rth0 = (struct ip6_rthdr0 *) 1056 (mtod(m, caddr_t) + eoff); 1057 #else 1058 IP6_EXTHDR_GET(rth0, 1059 struct ip6_rthdr0 *, m, 1060 eoff, rthlen); 1061 if (rth0 == NULL) { 1062 ICMP6STAT_INC(icp6s_tooshort); 1063 return (-1); 1064 } 1065 #endif 1066 /* just ignore a bogus header */ 1067 if ((rth0->ip6r0_len % 2) == 0 && 1068 (hops = rth0->ip6r0_len/2)) 1069 finaldst = (struct in6_addr *)(rth0 + 1) + (hops - 1); 1070 } 1071 eoff += rthlen; 1072 nxt = rth->ip6r_nxt; 1073 break; 1074 case IPPROTO_FRAGMENT: 1075 #ifndef PULLDOWN_TEST 1076 IP6_EXTHDR_CHECK(m, 0, eoff + 1077 sizeof(struct ip6_frag), -1); 1078 fh = (struct ip6_frag *)(mtod(m, caddr_t) + 1079 eoff); 1080 #else 1081 IP6_EXTHDR_GET(fh, struct ip6_frag *, m, 1082 eoff, sizeof(*fh)); 1083 if (fh == NULL) { 1084 ICMP6STAT_INC(icp6s_tooshort); 1085 return (-1); 1086 } 1087 #endif 1088 /* 1089 * Data after a fragment header is meaningless 1090 * unless it is the first fragment, but 1091 * we'll go to the notify label for path MTU 1092 * discovery. 1093 */ 1094 if (fh->ip6f_offlg & IP6F_OFF_MASK) 1095 goto notify; 1096 1097 eoff += sizeof(struct ip6_frag); 1098 nxt = fh->ip6f_nxt; 1099 break; 1100 default: 1101 /* 1102 * This case includes ESP and the No Next 1103 * Header. In such cases going to the notify 1104 * label does not have any meaning 1105 * (i.e. ctlfunc will be NULL), but we go 1106 * anyway since we might have to update 1107 * path MTU information. 1108 */ 1109 goto notify; 1110 } 1111 } 1112 notify: 1113 #ifndef PULLDOWN_TEST 1114 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 1115 #else 1116 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, 1117 sizeof(*icmp6) + sizeof(struct ip6_hdr)); 1118 if (icmp6 == NULL) { 1119 ICMP6STAT_INC(icp6s_tooshort); 1120 return (-1); 1121 } 1122 #endif 1123 1124 /* 1125 * retrieve parameters from the inner IPv6 header, and convert 1126 * them into sockaddr structures. 1127 * XXX: there is no guarantee that the source or destination 1128 * addresses of the inner packet are in the same scope as 1129 * the addresses of the icmp packet. But there is no other 1130 * way to determine the zone. 1131 */ 1132 eip6 = (struct ip6_hdr *)(icmp6 + 1); 1133 1134 bzero(&icmp6dst, sizeof(icmp6dst)); 1135 icmp6dst.sin6_len = sizeof(struct sockaddr_in6); 1136 icmp6dst.sin6_family = AF_INET6; 1137 if (finaldst == NULL) 1138 icmp6dst.sin6_addr = eip6->ip6_dst; 1139 else 1140 icmp6dst.sin6_addr = *finaldst; 1141 if (in6_setscope(&icmp6dst.sin6_addr, m->m_pkthdr.rcvif, NULL)) 1142 goto freeit; 1143 bzero(&icmp6src, sizeof(icmp6src)); 1144 icmp6src.sin6_len = sizeof(struct sockaddr_in6); 1145 icmp6src.sin6_family = AF_INET6; 1146 icmp6src.sin6_addr = eip6->ip6_src; 1147 if (in6_setscope(&icmp6src.sin6_addr, m->m_pkthdr.rcvif, NULL)) 1148 goto freeit; 1149 icmp6src.sin6_flowinfo = 1150 (eip6->ip6_flow & IPV6_FLOWLABEL_MASK); 1151 1152 if (finaldst == NULL) 1153 finaldst = &eip6->ip6_dst; 1154 ip6cp.ip6c_m = m; 1155 ip6cp.ip6c_icmp6 = icmp6; 1156 ip6cp.ip6c_ip6 = (struct ip6_hdr *)(icmp6 + 1); 1157 ip6cp.ip6c_off = eoff; 1158 ip6cp.ip6c_finaldst = finaldst; 1159 ip6cp.ip6c_src = &icmp6src; 1160 ip6cp.ip6c_nxt = nxt; 1161 1162 if (icmp6type == ICMP6_PACKET_TOO_BIG) { 1163 notifymtu = ntohl(icmp6->icmp6_mtu); 1164 ip6cp.ip6c_cmdarg = (void *)¬ifymtu; 1165 icmp6_mtudisc_update(&ip6cp, 1); /*XXX*/ 1166 } 1167 1168 ctlfunc = (void (*)(int, struct sockaddr *, void *)) 1169 (inet6sw[ip6_protox[nxt]].pr_ctlinput); 1170 if (ctlfunc) { 1171 (void) (*ctlfunc)(code, (struct sockaddr *)&icmp6dst, 1172 &ip6cp); 1173 } 1174 } 1175 *mp = m; 1176 return (0); 1177 1178 freeit: 1179 m_freem(m); 1180 return (-1); 1181 } 1182 1183 void 1184 icmp6_mtudisc_update(struct ip6ctlparam *ip6cp, int validated) 1185 { 1186 struct in6_addr *dst = ip6cp->ip6c_finaldst; 1187 struct icmp6_hdr *icmp6 = ip6cp->ip6c_icmp6; 1188 struct mbuf *m = ip6cp->ip6c_m; /* will be necessary for scope issue */ 1189 u_int mtu = ntohl(icmp6->icmp6_mtu); 1190 struct in_conninfo inc; 1191 1192 #if 0 1193 /* 1194 * RFC2460 section 5, last paragraph. 1195 * even though minimum link MTU for IPv6 is IPV6_MMTU, 1196 * we may see ICMPv6 too big with mtu < IPV6_MMTU 1197 * due to packet translator in the middle. 1198 * see ip6_output() and ip6_getpmtu() "alwaysfrag" case for 1199 * special handling. 1200 */ 1201 if (mtu < IPV6_MMTU) 1202 return; 1203 #endif 1204 1205 /* 1206 * we reject ICMPv6 too big with abnormally small value. 1207 * XXX what is the good definition of "abnormally small"? 1208 */ 1209 if (mtu < sizeof(struct ip6_hdr) + sizeof(struct ip6_frag) + 8) 1210 return; 1211 1212 if (!validated) 1213 return; 1214 1215 /* 1216 * In case the suggested mtu is less than IPV6_MMTU, we 1217 * only need to remember that it was for above mentioned 1218 * "alwaysfrag" case. 1219 * Try to be as close to the spec as possible. 1220 */ 1221 if (mtu < IPV6_MMTU) 1222 mtu = IPV6_MMTU - 8; 1223 1224 bzero(&inc, sizeof(inc)); 1225 inc.inc_flags |= INC_ISIPV6; 1226 inc.inc6_faddr = *dst; 1227 if (in6_setscope(&inc.inc6_faddr, m->m_pkthdr.rcvif, NULL)) 1228 return; 1229 1230 if (mtu < tcp_maxmtu6(&inc, NULL)) { 1231 tcp_hc_updatemtu(&inc, mtu); 1232 ICMP6STAT_INC(icp6s_pmtuchg); 1233 } 1234 } 1235 1236 /* 1237 * Process a Node Information Query packet, based on 1238 * draft-ietf-ipngwg-icmp-name-lookups-07. 1239 * 1240 * Spec incompatibilities: 1241 * - IPv6 Subject address handling 1242 * - IPv4 Subject address handling support missing 1243 * - Proxy reply (answer even if it's not for me) 1244 * - joins NI group address at in6_ifattach() time only, does not cope 1245 * with hostname changes by sethostname(3) 1246 */ 1247 static struct mbuf * 1248 ni6_input(struct mbuf *m, int off) 1249 { 1250 struct icmp6_nodeinfo *ni6, *nni6; 1251 struct mbuf *n = NULL; 1252 struct prison *pr; 1253 u_int16_t qtype; 1254 int subjlen; 1255 int replylen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo); 1256 struct ni_reply_fqdn *fqdn; 1257 int addrs; /* for NI_QTYPE_NODEADDR */ 1258 struct ifnet *ifp = NULL; /* for NI_QTYPE_NODEADDR */ 1259 struct in6_addr in6_subj; /* subject address */ 1260 struct ip6_hdr *ip6; 1261 int oldfqdn = 0; /* if 1, return pascal string (03 draft) */ 1262 char *subj = NULL; 1263 struct in6_ifaddr *ia6 = NULL; 1264 1265 ip6 = mtod(m, struct ip6_hdr *); 1266 #ifndef PULLDOWN_TEST 1267 ni6 = (struct icmp6_nodeinfo *)(mtod(m, caddr_t) + off); 1268 #else 1269 IP6_EXTHDR_GET(ni6, struct icmp6_nodeinfo *, m, off, sizeof(*ni6)); 1270 if (ni6 == NULL) { 1271 /* m is already reclaimed */ 1272 return (NULL); 1273 } 1274 #endif 1275 1276 /* 1277 * Validate IPv6 source address. 1278 * The default configuration MUST be to refuse answering queries from 1279 * global-scope addresses according to RFC4602. 1280 * Notes: 1281 * - it's not very clear what "refuse" means; this implementation 1282 * simply drops it. 1283 * - it's not very easy to identify global-scope (unicast) addresses 1284 * since there are many prefixes for them. It should be safer 1285 * and in practice sufficient to check "all" but loopback and 1286 * link-local (note that site-local unicast was deprecated and 1287 * ULA is defined as global scope-wise) 1288 */ 1289 if ((V_icmp6_nodeinfo & ICMP6_NODEINFO_GLOBALOK) == 0 && 1290 !IN6_IS_ADDR_LOOPBACK(&ip6->ip6_src) && 1291 !IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_src)) 1292 goto bad; 1293 1294 /* 1295 * Validate IPv6 destination address. 1296 * 1297 * The Responder must discard the Query without further processing 1298 * unless it is one of the Responder's unicast or anycast addresses, or 1299 * a link-local scope multicast address which the Responder has joined. 1300 * [RFC4602, Section 5.] 1301 */ 1302 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 1303 if (!IN6_IS_ADDR_MC_LINKLOCAL(&ip6->ip6_dst)) 1304 goto bad; 1305 /* else it's a link-local multicast, fine */ 1306 } else { /* unicast or anycast */ 1307 if ((ia6 = ip6_getdstifaddr(m)) == NULL) 1308 goto bad; /* XXX impossible */ 1309 1310 if ((ia6->ia6_flags & IN6_IFF_TEMPORARY) && 1311 !(V_icmp6_nodeinfo & ICMP6_NODEINFO_TMPADDROK)) { 1312 ifa_free(&ia6->ia_ifa); 1313 nd6log((LOG_DEBUG, "ni6_input: ignore node info to " 1314 "a temporary address in %s:%d", 1315 __FILE__, __LINE__)); 1316 goto bad; 1317 } 1318 ifa_free(&ia6->ia_ifa); 1319 } 1320 1321 /* validate query Subject field. */ 1322 qtype = ntohs(ni6->ni_qtype); 1323 subjlen = m->m_pkthdr.len - off - sizeof(struct icmp6_nodeinfo); 1324 switch (qtype) { 1325 case NI_QTYPE_NOOP: 1326 case NI_QTYPE_SUPTYPES: 1327 /* 07 draft */ 1328 if (ni6->ni_code == ICMP6_NI_SUBJ_FQDN && subjlen == 0) 1329 break; 1330 /* FALLTHROUGH */ 1331 case NI_QTYPE_FQDN: 1332 case NI_QTYPE_NODEADDR: 1333 case NI_QTYPE_IPV4ADDR: 1334 switch (ni6->ni_code) { 1335 case ICMP6_NI_SUBJ_IPV6: 1336 #if ICMP6_NI_SUBJ_IPV6 != 0 1337 case 0: 1338 #endif 1339 /* 1340 * backward compatibility - try to accept 03 draft 1341 * format, where no Subject is present. 1342 */ 1343 if (qtype == NI_QTYPE_FQDN && ni6->ni_code == 0 && 1344 subjlen == 0) { 1345 oldfqdn++; 1346 break; 1347 } 1348 #if ICMP6_NI_SUBJ_IPV6 != 0 1349 if (ni6->ni_code != ICMP6_NI_SUBJ_IPV6) 1350 goto bad; 1351 #endif 1352 1353 if (subjlen != sizeof(struct in6_addr)) 1354 goto bad; 1355 1356 /* 1357 * Validate Subject address. 1358 * 1359 * Not sure what exactly "address belongs to the node" 1360 * means in the spec, is it just unicast, or what? 1361 * 1362 * At this moment we consider Subject address as 1363 * "belong to the node" if the Subject address equals 1364 * to the IPv6 destination address; validation for 1365 * IPv6 destination address should have done enough 1366 * check for us. 1367 * 1368 * We do not do proxy at this moment. 1369 */ 1370 /* m_pulldown instead of copy? */ 1371 m_copydata(m, off + sizeof(struct icmp6_nodeinfo), 1372 subjlen, (caddr_t)&in6_subj); 1373 if (in6_setscope(&in6_subj, m->m_pkthdr.rcvif, NULL)) 1374 goto bad; 1375 1376 subj = (char *)&in6_subj; 1377 if (IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, &in6_subj)) 1378 break; 1379 1380 /* 1381 * XXX if we are to allow other cases, we should really 1382 * be careful about scope here. 1383 * basically, we should disallow queries toward IPv6 1384 * destination X with subject Y, 1385 * if scope(X) > scope(Y). 1386 * if we allow scope(X) > scope(Y), it will result in 1387 * information leakage across scope boundary. 1388 */ 1389 goto bad; 1390 1391 case ICMP6_NI_SUBJ_FQDN: 1392 /* 1393 * Validate Subject name with gethostname(3). 1394 * 1395 * The behavior may need some debate, since: 1396 * - we are not sure if the node has FQDN as 1397 * hostname (returned by gethostname(3)). 1398 * - the code does wildcard match for truncated names. 1399 * however, we are not sure if we want to perform 1400 * wildcard match, if gethostname(3) side has 1401 * truncated hostname. 1402 */ 1403 pr = curthread->td_ucred->cr_prison; 1404 mtx_lock(&pr->pr_mtx); 1405 n = ni6_nametodns(pr->pr_hostname, 1406 strlen(pr->pr_hostname), 0); 1407 mtx_unlock(&pr->pr_mtx); 1408 if (!n || n->m_next || n->m_len == 0) 1409 goto bad; 1410 IP6_EXTHDR_GET(subj, char *, m, 1411 off + sizeof(struct icmp6_nodeinfo), subjlen); 1412 if (subj == NULL) 1413 goto bad; 1414 if (!ni6_dnsmatch(subj, subjlen, mtod(n, const char *), 1415 n->m_len)) { 1416 goto bad; 1417 } 1418 m_freem(n); 1419 n = NULL; 1420 break; 1421 1422 case ICMP6_NI_SUBJ_IPV4: /* XXX: to be implemented? */ 1423 default: 1424 goto bad; 1425 } 1426 break; 1427 } 1428 1429 /* refuse based on configuration. XXX ICMP6_NI_REFUSED? */ 1430 switch (qtype) { 1431 case NI_QTYPE_FQDN: 1432 if ((V_icmp6_nodeinfo & ICMP6_NODEINFO_FQDNOK) == 0) 1433 goto bad; 1434 break; 1435 case NI_QTYPE_NODEADDR: 1436 case NI_QTYPE_IPV4ADDR: 1437 if ((V_icmp6_nodeinfo & ICMP6_NODEINFO_NODEADDROK) == 0) 1438 goto bad; 1439 break; 1440 } 1441 1442 /* guess reply length */ 1443 switch (qtype) { 1444 case NI_QTYPE_NOOP: 1445 break; /* no reply data */ 1446 case NI_QTYPE_SUPTYPES: 1447 replylen += sizeof(u_int32_t); 1448 break; 1449 case NI_QTYPE_FQDN: 1450 /* XXX will append an mbuf */ 1451 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1452 break; 1453 case NI_QTYPE_NODEADDR: 1454 addrs = ni6_addrs(ni6, m, &ifp, (struct in6_addr *)subj); 1455 if ((replylen += addrs * (sizeof(struct in6_addr) + 1456 sizeof(u_int32_t))) > MCLBYTES) 1457 replylen = MCLBYTES; /* XXX: will truncate pkt later */ 1458 break; 1459 case NI_QTYPE_IPV4ADDR: 1460 /* unsupported - should respond with unknown Qtype? */ 1461 break; 1462 default: 1463 /* 1464 * XXX: We must return a reply with the ICMP6 code 1465 * `unknown Qtype' in this case. However we regard the case 1466 * as an FQDN query for backward compatibility. 1467 * Older versions set a random value to this field, 1468 * so it rarely varies in the defined qtypes. 1469 * But the mechanism is not reliable... 1470 * maybe we should obsolete older versions. 1471 */ 1472 qtype = NI_QTYPE_FQDN; 1473 /* XXX will append an mbuf */ 1474 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1475 oldfqdn++; 1476 break; 1477 } 1478 1479 /* Allocate an mbuf to reply. */ 1480 if (replylen > MCLBYTES) { 1481 /* 1482 * XXX: should we try to allocate more? But MCLBYTES 1483 * is probably much larger than IPV6_MMTU... 1484 */ 1485 goto bad; 1486 } 1487 if (replylen > MHLEN) 1488 n = m_getcl(M_NOWAIT, m->m_type, M_PKTHDR); 1489 else 1490 n = m_gethdr(M_NOWAIT, m->m_type); 1491 if (n == NULL) { 1492 m_freem(m); 1493 return (NULL); 1494 } 1495 m_move_pkthdr(n, m); /* just for recvif and FIB */ 1496 n->m_pkthdr.len = n->m_len = replylen; 1497 1498 /* copy mbuf header and IPv6 + Node Information base headers */ 1499 bcopy(mtod(m, caddr_t), mtod(n, caddr_t), sizeof(struct ip6_hdr)); 1500 nni6 = (struct icmp6_nodeinfo *)(mtod(n, struct ip6_hdr *) + 1); 1501 bcopy((caddr_t)ni6, (caddr_t)nni6, sizeof(struct icmp6_nodeinfo)); 1502 1503 /* qtype dependent procedure */ 1504 switch (qtype) { 1505 case NI_QTYPE_NOOP: 1506 nni6->ni_code = ICMP6_NI_SUCCESS; 1507 nni6->ni_flags = 0; 1508 break; 1509 case NI_QTYPE_SUPTYPES: 1510 { 1511 u_int32_t v; 1512 nni6->ni_code = ICMP6_NI_SUCCESS; 1513 nni6->ni_flags = htons(0x0000); /* raw bitmap */ 1514 /* supports NOOP, SUPTYPES, FQDN, and NODEADDR */ 1515 v = (u_int32_t)htonl(0x0000000f); 1516 bcopy(&v, nni6 + 1, sizeof(u_int32_t)); 1517 break; 1518 } 1519 case NI_QTYPE_FQDN: 1520 nni6->ni_code = ICMP6_NI_SUCCESS; 1521 fqdn = (struct ni_reply_fqdn *)(mtod(n, caddr_t) + 1522 sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo)); 1523 nni6->ni_flags = 0; /* XXX: meaningless TTL */ 1524 fqdn->ni_fqdn_ttl = 0; /* ditto. */ 1525 /* 1526 * XXX do we really have FQDN in hostname? 1527 */ 1528 pr = curthread->td_ucred->cr_prison; 1529 mtx_lock(&pr->pr_mtx); 1530 n->m_next = ni6_nametodns(pr->pr_hostname, 1531 strlen(pr->pr_hostname), oldfqdn); 1532 mtx_unlock(&pr->pr_mtx); 1533 if (n->m_next == NULL) 1534 goto bad; 1535 /* XXX we assume that n->m_next is not a chain */ 1536 if (n->m_next->m_next != NULL) 1537 goto bad; 1538 n->m_pkthdr.len += n->m_next->m_len; 1539 break; 1540 case NI_QTYPE_NODEADDR: 1541 { 1542 int lenlim, copied; 1543 1544 nni6->ni_code = ICMP6_NI_SUCCESS; 1545 n->m_pkthdr.len = n->m_len = 1546 sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo); 1547 lenlim = M_TRAILINGSPACE(n); 1548 copied = ni6_store_addrs(ni6, nni6, ifp, lenlim); 1549 /* XXX: reset mbuf length */ 1550 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) + 1551 sizeof(struct icmp6_nodeinfo) + copied; 1552 break; 1553 } 1554 default: 1555 break; /* XXX impossible! */ 1556 } 1557 1558 nni6->ni_type = ICMP6_NI_REPLY; 1559 m_freem(m); 1560 return (n); 1561 1562 bad: 1563 m_freem(m); 1564 if (n) 1565 m_freem(n); 1566 return (NULL); 1567 } 1568 1569 /* 1570 * make a mbuf with DNS-encoded string. no compression support. 1571 * 1572 * XXX names with less than 2 dots (like "foo" or "foo.section") will be 1573 * treated as truncated name (two \0 at the end). this is a wild guess. 1574 * 1575 * old - return pascal string if non-zero 1576 */ 1577 static struct mbuf * 1578 ni6_nametodns(const char *name, int namelen, int old) 1579 { 1580 struct mbuf *m; 1581 char *cp, *ep; 1582 const char *p, *q; 1583 int i, len, nterm; 1584 1585 if (old) 1586 len = namelen + 1; 1587 else 1588 len = MCLBYTES; 1589 1590 /* Because MAXHOSTNAMELEN is usually 256, we use cluster mbuf. */ 1591 if (len > MLEN) 1592 m = m_getcl(M_NOWAIT, MT_DATA, 0); 1593 else 1594 m = m_get(M_NOWAIT, MT_DATA); 1595 if (m == NULL) 1596 goto fail; 1597 1598 if (old) { 1599 m->m_len = len; 1600 *mtod(m, char *) = namelen; 1601 bcopy(name, mtod(m, char *) + 1, namelen); 1602 return m; 1603 } else { 1604 m->m_len = 0; 1605 cp = mtod(m, char *); 1606 ep = mtod(m, char *) + M_TRAILINGSPACE(m); 1607 1608 /* if not certain about my name, return empty buffer */ 1609 if (namelen == 0) 1610 return m; 1611 1612 /* 1613 * guess if it looks like shortened hostname, or FQDN. 1614 * shortened hostname needs two trailing "\0". 1615 */ 1616 i = 0; 1617 for (p = name; p < name + namelen; p++) { 1618 if (*p && *p == '.') 1619 i++; 1620 } 1621 if (i < 2) 1622 nterm = 2; 1623 else 1624 nterm = 1; 1625 1626 p = name; 1627 while (cp < ep && p < name + namelen) { 1628 i = 0; 1629 for (q = p; q < name + namelen && *q && *q != '.'; q++) 1630 i++; 1631 /* result does not fit into mbuf */ 1632 if (cp + i + 1 >= ep) 1633 goto fail; 1634 /* 1635 * DNS label length restriction, RFC1035 page 8. 1636 * "i == 0" case is included here to avoid returning 1637 * 0-length label on "foo..bar". 1638 */ 1639 if (i <= 0 || i >= 64) 1640 goto fail; 1641 *cp++ = i; 1642 bcopy(p, cp, i); 1643 cp += i; 1644 p = q; 1645 if (p < name + namelen && *p == '.') 1646 p++; 1647 } 1648 /* termination */ 1649 if (cp + nterm >= ep) 1650 goto fail; 1651 while (nterm-- > 0) 1652 *cp++ = '\0'; 1653 m->m_len = cp - mtod(m, char *); 1654 return m; 1655 } 1656 1657 panic("should not reach here"); 1658 /* NOTREACHED */ 1659 1660 fail: 1661 if (m) 1662 m_freem(m); 1663 return NULL; 1664 } 1665 1666 /* 1667 * check if two DNS-encoded string matches. takes care of truncated 1668 * form (with \0\0 at the end). no compression support. 1669 * XXX upper/lowercase match (see RFC2065) 1670 */ 1671 static int 1672 ni6_dnsmatch(const char *a, int alen, const char *b, int blen) 1673 { 1674 const char *a0, *b0; 1675 int l; 1676 1677 /* simplest case - need validation? */ 1678 if (alen == blen && bcmp(a, b, alen) == 0) 1679 return 1; 1680 1681 a0 = a; 1682 b0 = b; 1683 1684 /* termination is mandatory */ 1685 if (alen < 2 || blen < 2) 1686 return 0; 1687 if (a0[alen - 1] != '\0' || b0[blen - 1] != '\0') 1688 return 0; 1689 alen--; 1690 blen--; 1691 1692 while (a - a0 < alen && b - b0 < blen) { 1693 if (a - a0 + 1 > alen || b - b0 + 1 > blen) 1694 return 0; 1695 1696 if ((signed char)a[0] < 0 || (signed char)b[0] < 0) 1697 return 0; 1698 /* we don't support compression yet */ 1699 if (a[0] >= 64 || b[0] >= 64) 1700 return 0; 1701 1702 /* truncated case */ 1703 if (a[0] == 0 && a - a0 == alen - 1) 1704 return 1; 1705 if (b[0] == 0 && b - b0 == blen - 1) 1706 return 1; 1707 if (a[0] == 0 || b[0] == 0) 1708 return 0; 1709 1710 if (a[0] != b[0]) 1711 return 0; 1712 l = a[0]; 1713 if (a - a0 + 1 + l > alen || b - b0 + 1 + l > blen) 1714 return 0; 1715 if (bcmp(a + 1, b + 1, l) != 0) 1716 return 0; 1717 1718 a += 1 + l; 1719 b += 1 + l; 1720 } 1721 1722 if (a - a0 == alen && b - b0 == blen) 1723 return 1; 1724 else 1725 return 0; 1726 } 1727 1728 /* 1729 * calculate the number of addresses to be returned in the node info reply. 1730 */ 1731 static int 1732 ni6_addrs(struct icmp6_nodeinfo *ni6, struct mbuf *m, struct ifnet **ifpp, 1733 struct in6_addr *subj) 1734 { 1735 struct ifnet *ifp; 1736 struct in6_ifaddr *ifa6; 1737 struct ifaddr *ifa; 1738 int addrs = 0, addrsofif, iffound = 0; 1739 int niflags = ni6->ni_flags; 1740 1741 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0) { 1742 switch (ni6->ni_code) { 1743 case ICMP6_NI_SUBJ_IPV6: 1744 if (subj == NULL) /* must be impossible... */ 1745 return (0); 1746 break; 1747 default: 1748 /* 1749 * XXX: we only support IPv6 subject address for 1750 * this Qtype. 1751 */ 1752 return (0); 1753 } 1754 } 1755 1756 IFNET_RLOCK_NOSLEEP(); 1757 TAILQ_FOREACH(ifp, &V_ifnet, if_list) { 1758 addrsofif = 0; 1759 IF_ADDR_RLOCK(ifp); 1760 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 1761 if (ifa->ifa_addr->sa_family != AF_INET6) 1762 continue; 1763 ifa6 = (struct in6_ifaddr *)ifa; 1764 1765 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0 && 1766 IN6_ARE_ADDR_EQUAL(subj, &ifa6->ia_addr.sin6_addr)) 1767 iffound = 1; 1768 1769 /* 1770 * IPv4-mapped addresses can only be returned by a 1771 * Node Information proxy, since they represent 1772 * addresses of IPv4-only nodes, which perforce do 1773 * not implement this protocol. 1774 * [icmp-name-lookups-07, Section 5.4] 1775 * So we don't support NI_NODEADDR_FLAG_COMPAT in 1776 * this function at this moment. 1777 */ 1778 1779 /* What do we have to do about ::1? */ 1780 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1781 case IPV6_ADDR_SCOPE_LINKLOCAL: 1782 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0) 1783 continue; 1784 break; 1785 case IPV6_ADDR_SCOPE_SITELOCAL: 1786 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0) 1787 continue; 1788 break; 1789 case IPV6_ADDR_SCOPE_GLOBAL: 1790 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0) 1791 continue; 1792 break; 1793 default: 1794 continue; 1795 } 1796 1797 /* 1798 * check if anycast is okay. 1799 * XXX: just experimental. not in the spec. 1800 */ 1801 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 && 1802 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0) 1803 continue; /* we need only unicast addresses */ 1804 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 1805 (V_icmp6_nodeinfo & ICMP6_NODEINFO_TMPADDROK) == 0) { 1806 continue; 1807 } 1808 addrsofif++; /* count the address */ 1809 } 1810 IF_ADDR_RUNLOCK(ifp); 1811 if (iffound) { 1812 *ifpp = ifp; 1813 IFNET_RUNLOCK_NOSLEEP(); 1814 return (addrsofif); 1815 } 1816 1817 addrs += addrsofif; 1818 } 1819 IFNET_RUNLOCK_NOSLEEP(); 1820 1821 return (addrs); 1822 } 1823 1824 static int 1825 ni6_store_addrs(struct icmp6_nodeinfo *ni6, struct icmp6_nodeinfo *nni6, 1826 struct ifnet *ifp0, int resid) 1827 { 1828 struct ifnet *ifp; 1829 struct in6_ifaddr *ifa6; 1830 struct ifaddr *ifa; 1831 struct ifnet *ifp_dep = NULL; 1832 int copied = 0, allow_deprecated = 0; 1833 u_char *cp = (u_char *)(nni6 + 1); 1834 int niflags = ni6->ni_flags; 1835 u_int32_t ltime; 1836 1837 if (ifp0 == NULL && !(niflags & NI_NODEADDR_FLAG_ALL)) 1838 return (0); /* needless to copy */ 1839 1840 IFNET_RLOCK_NOSLEEP(); 1841 ifp = ifp0 ? ifp0 : TAILQ_FIRST(&V_ifnet); 1842 again: 1843 1844 for (; ifp; ifp = TAILQ_NEXT(ifp, if_list)) { 1845 IF_ADDR_RLOCK(ifp); 1846 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 1847 if (ifa->ifa_addr->sa_family != AF_INET6) 1848 continue; 1849 ifa6 = (struct in6_ifaddr *)ifa; 1850 1851 if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) != 0 && 1852 allow_deprecated == 0) { 1853 /* 1854 * prefererred address should be put before 1855 * deprecated addresses. 1856 */ 1857 1858 /* record the interface for later search */ 1859 if (ifp_dep == NULL) 1860 ifp_dep = ifp; 1861 1862 continue; 1863 } else if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) == 0 && 1864 allow_deprecated != 0) 1865 continue; /* we now collect deprecated addrs */ 1866 1867 /* What do we have to do about ::1? */ 1868 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1869 case IPV6_ADDR_SCOPE_LINKLOCAL: 1870 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0) 1871 continue; 1872 break; 1873 case IPV6_ADDR_SCOPE_SITELOCAL: 1874 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0) 1875 continue; 1876 break; 1877 case IPV6_ADDR_SCOPE_GLOBAL: 1878 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0) 1879 continue; 1880 break; 1881 default: 1882 continue; 1883 } 1884 1885 /* 1886 * check if anycast is okay. 1887 * XXX: just experimental. not in the spec. 1888 */ 1889 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 && 1890 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0) 1891 continue; 1892 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 1893 (V_icmp6_nodeinfo & ICMP6_NODEINFO_TMPADDROK) == 0) { 1894 continue; 1895 } 1896 1897 /* now we can copy the address */ 1898 if (resid < sizeof(struct in6_addr) + 1899 sizeof(u_int32_t)) { 1900 IF_ADDR_RUNLOCK(ifp); 1901 /* 1902 * We give up much more copy. 1903 * Set the truncate flag and return. 1904 */ 1905 nni6->ni_flags |= NI_NODEADDR_FLAG_TRUNCATE; 1906 IFNET_RUNLOCK_NOSLEEP(); 1907 return (copied); 1908 } 1909 1910 /* 1911 * Set the TTL of the address. 1912 * The TTL value should be one of the following 1913 * according to the specification: 1914 * 1915 * 1. The remaining lifetime of a DHCP lease on the 1916 * address, or 1917 * 2. The remaining Valid Lifetime of a prefix from 1918 * which the address was derived through Stateless 1919 * Autoconfiguration. 1920 * 1921 * Note that we currently do not support stateful 1922 * address configuration by DHCPv6, so the former 1923 * case can't happen. 1924 */ 1925 if (ifa6->ia6_lifetime.ia6t_expire == 0) 1926 ltime = ND6_INFINITE_LIFETIME; 1927 else { 1928 if (ifa6->ia6_lifetime.ia6t_expire > 1929 time_second) 1930 ltime = htonl(ifa6->ia6_lifetime.ia6t_expire - time_second); 1931 else 1932 ltime = 0; 1933 } 1934 1935 bcopy(<ime, cp, sizeof(u_int32_t)); 1936 cp += sizeof(u_int32_t); 1937 1938 /* copy the address itself */ 1939 bcopy(&ifa6->ia_addr.sin6_addr, cp, 1940 sizeof(struct in6_addr)); 1941 in6_clearscope((struct in6_addr *)cp); /* XXX */ 1942 cp += sizeof(struct in6_addr); 1943 1944 resid -= (sizeof(struct in6_addr) + sizeof(u_int32_t)); 1945 copied += (sizeof(struct in6_addr) + sizeof(u_int32_t)); 1946 } 1947 IF_ADDR_RUNLOCK(ifp); 1948 if (ifp0) /* we need search only on the specified IF */ 1949 break; 1950 } 1951 1952 if (allow_deprecated == 0 && ifp_dep != NULL) { 1953 ifp = ifp_dep; 1954 allow_deprecated = 1; 1955 1956 goto again; 1957 } 1958 1959 IFNET_RUNLOCK_NOSLEEP(); 1960 1961 return (copied); 1962 } 1963 1964 /* 1965 * XXX almost dup'ed code with rip6_input. 1966 */ 1967 static int 1968 icmp6_rip6_input(struct mbuf **mp, int off) 1969 { 1970 struct mbuf *m = *mp; 1971 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1972 struct inpcb *in6p; 1973 struct inpcb *last = NULL; 1974 struct sockaddr_in6 fromsa; 1975 struct icmp6_hdr *icmp6; 1976 struct mbuf *opts = NULL; 1977 1978 #ifndef PULLDOWN_TEST 1979 /* this is assumed to be safe. */ 1980 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off); 1981 #else 1982 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 1983 if (icmp6 == NULL) { 1984 /* m is already reclaimed */ 1985 return (IPPROTO_DONE); 1986 } 1987 #endif 1988 1989 /* 1990 * XXX: the address may have embedded scope zone ID, which should be 1991 * hidden from applications. 1992 */ 1993 bzero(&fromsa, sizeof(fromsa)); 1994 fromsa.sin6_family = AF_INET6; 1995 fromsa.sin6_len = sizeof(struct sockaddr_in6); 1996 fromsa.sin6_addr = ip6->ip6_src; 1997 if (sa6_recoverscope(&fromsa)) { 1998 m_freem(m); 1999 return (IPPROTO_DONE); 2000 } 2001 2002 INP_INFO_RLOCK(&V_ripcbinfo); 2003 LIST_FOREACH(in6p, &V_ripcb, inp_list) { 2004 if ((in6p->inp_vflag & INP_IPV6) == 0) 2005 continue; 2006 if (in6p->inp_ip_p != IPPROTO_ICMPV6) 2007 continue; 2008 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr) && 2009 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr, &ip6->ip6_dst)) 2010 continue; 2011 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr) && 2012 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr, &ip6->ip6_src)) 2013 continue; 2014 INP_RLOCK(in6p); 2015 if (ICMP6_FILTER_WILLBLOCK(icmp6->icmp6_type, 2016 in6p->in6p_icmp6filt)) { 2017 INP_RUNLOCK(in6p); 2018 continue; 2019 } 2020 if (last != NULL) { 2021 struct mbuf *n = NULL; 2022 2023 /* 2024 * Recent network drivers tend to allocate a single 2025 * mbuf cluster, rather than to make a couple of 2026 * mbufs without clusters. Also, since the IPv6 code 2027 * path tries to avoid m_pullup(), it is highly 2028 * probable that we still have an mbuf cluster here 2029 * even though the necessary length can be stored in an 2030 * mbuf's internal buffer. 2031 * Meanwhile, the default size of the receive socket 2032 * buffer for raw sockets is not so large. This means 2033 * the possibility of packet loss is relatively higher 2034 * than before. To avoid this scenario, we copy the 2035 * received data to a separate mbuf that does not use 2036 * a cluster, if possible. 2037 * XXX: it is better to copy the data after stripping 2038 * intermediate headers. 2039 */ 2040 if ((m->m_flags & M_EXT) && m->m_next == NULL && 2041 m->m_len <= MHLEN) { 2042 n = m_get(M_NOWAIT, m->m_type); 2043 if (n != NULL) { 2044 if (m_dup_pkthdr(n, m, M_NOWAIT)) { 2045 bcopy(m->m_data, n->m_data, 2046 m->m_len); 2047 n->m_len = m->m_len; 2048 } else { 2049 m_free(n); 2050 n = NULL; 2051 } 2052 } 2053 } 2054 if (n != NULL || 2055 (n = m_copy(m, 0, (int)M_COPYALL)) != NULL) { 2056 if (last->inp_flags & INP_CONTROLOPTS) 2057 ip6_savecontrol(last, n, &opts); 2058 /* strip intermediate headers */ 2059 m_adj(n, off); 2060 SOCKBUF_LOCK(&last->inp_socket->so_rcv); 2061 if (sbappendaddr_locked( 2062 &last->inp_socket->so_rcv, 2063 (struct sockaddr *)&fromsa, n, opts) 2064 == 0) { 2065 /* should notify about lost packet */ 2066 m_freem(n); 2067 if (opts) { 2068 m_freem(opts); 2069 } 2070 SOCKBUF_UNLOCK( 2071 &last->inp_socket->so_rcv); 2072 } else 2073 sorwakeup_locked(last->inp_socket); 2074 opts = NULL; 2075 } 2076 INP_RUNLOCK(last); 2077 } 2078 last = in6p; 2079 } 2080 INP_INFO_RUNLOCK(&V_ripcbinfo); 2081 if (last != NULL) { 2082 if (last->inp_flags & INP_CONTROLOPTS) 2083 ip6_savecontrol(last, m, &opts); 2084 /* strip intermediate headers */ 2085 m_adj(m, off); 2086 2087 /* avoid using mbuf clusters if possible (see above) */ 2088 if ((m->m_flags & M_EXT) && m->m_next == NULL && 2089 m->m_len <= MHLEN) { 2090 struct mbuf *n; 2091 2092 n = m_get(M_NOWAIT, m->m_type); 2093 if (n != NULL) { 2094 if (m_dup_pkthdr(n, m, M_NOWAIT)) { 2095 bcopy(m->m_data, n->m_data, m->m_len); 2096 n->m_len = m->m_len; 2097 2098 m_freem(m); 2099 m = n; 2100 } else { 2101 m_freem(n); 2102 n = NULL; 2103 } 2104 } 2105 } 2106 SOCKBUF_LOCK(&last->inp_socket->so_rcv); 2107 if (sbappendaddr_locked(&last->inp_socket->so_rcv, 2108 (struct sockaddr *)&fromsa, m, opts) == 0) { 2109 m_freem(m); 2110 if (opts) 2111 m_freem(opts); 2112 SOCKBUF_UNLOCK(&last->inp_socket->so_rcv); 2113 } else 2114 sorwakeup_locked(last->inp_socket); 2115 INP_RUNLOCK(last); 2116 } else { 2117 m_freem(m); 2118 IP6STAT_DEC(ip6s_delivered); 2119 } 2120 return IPPROTO_DONE; 2121 } 2122 2123 /* 2124 * Reflect the ip6 packet back to the source. 2125 * OFF points to the icmp6 header, counted from the top of the mbuf. 2126 */ 2127 void 2128 icmp6_reflect(struct mbuf *m, size_t off) 2129 { 2130 struct ip6_hdr *ip6; 2131 struct icmp6_hdr *icmp6; 2132 struct in6_ifaddr *ia = NULL; 2133 int plen; 2134 int type, code; 2135 struct ifnet *outif = NULL; 2136 struct in6_addr origdst, src, *srcp = NULL; 2137 2138 /* too short to reflect */ 2139 if (off < sizeof(struct ip6_hdr)) { 2140 nd6log((LOG_DEBUG, 2141 "sanity fail: off=%lx, sizeof(ip6)=%lx in %s:%d\n", 2142 (u_long)off, (u_long)sizeof(struct ip6_hdr), 2143 __FILE__, __LINE__)); 2144 goto bad; 2145 } 2146 2147 /* 2148 * If there are extra headers between IPv6 and ICMPv6, strip 2149 * off that header first. 2150 */ 2151 #ifdef DIAGNOSTIC 2152 if (sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) > MHLEN) 2153 panic("assumption failed in icmp6_reflect"); 2154 #endif 2155 if (off > sizeof(struct ip6_hdr)) { 2156 size_t l; 2157 struct ip6_hdr nip6; 2158 2159 l = off - sizeof(struct ip6_hdr); 2160 m_copydata(m, 0, sizeof(nip6), (caddr_t)&nip6); 2161 m_adj(m, l); 2162 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 2163 if (m->m_len < l) { 2164 if ((m = m_pullup(m, l)) == NULL) 2165 return; 2166 } 2167 bcopy((caddr_t)&nip6, mtod(m, caddr_t), sizeof(nip6)); 2168 } else /* off == sizeof(struct ip6_hdr) */ { 2169 size_t l; 2170 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 2171 if (m->m_len < l) { 2172 if ((m = m_pullup(m, l)) == NULL) 2173 return; 2174 } 2175 } 2176 plen = m->m_pkthdr.len - sizeof(struct ip6_hdr); 2177 ip6 = mtod(m, struct ip6_hdr *); 2178 ip6->ip6_nxt = IPPROTO_ICMPV6; 2179 icmp6 = (struct icmp6_hdr *)(ip6 + 1); 2180 type = icmp6->icmp6_type; /* keep type for statistics */ 2181 code = icmp6->icmp6_code; /* ditto. */ 2182 2183 origdst = ip6->ip6_dst; 2184 /* 2185 * ip6_input() drops a packet if its src is multicast. 2186 * So, the src is never multicast. 2187 */ 2188 ip6->ip6_dst = ip6->ip6_src; 2189 2190 /* 2191 * If the incoming packet was addressed directly to us (i.e. unicast), 2192 * use dst as the src for the reply. 2193 * The IN6_IFF_NOTREADY case should be VERY rare, but is possible 2194 * (for example) when we encounter an error while forwarding procedure 2195 * destined to a duplicated address of ours. 2196 * Note that ip6_getdstifaddr() may fail if we are in an error handling 2197 * procedure of an outgoing packet of our own, in which case we need 2198 * to search in the ifaddr list. 2199 */ 2200 if (!IN6_IS_ADDR_MULTICAST(&origdst)) { 2201 if ((ia = ip6_getdstifaddr(m))) { 2202 if (!(ia->ia6_flags & 2203 (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY))) 2204 srcp = &ia->ia_addr.sin6_addr; 2205 } else { 2206 struct sockaddr_in6 d; 2207 2208 bzero(&d, sizeof(d)); 2209 d.sin6_family = AF_INET6; 2210 d.sin6_len = sizeof(d); 2211 d.sin6_addr = origdst; 2212 ia = (struct in6_ifaddr *) 2213 ifa_ifwithaddr((struct sockaddr *)&d); 2214 if (ia && 2215 !(ia->ia6_flags & 2216 (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY))) { 2217 srcp = &ia->ia_addr.sin6_addr; 2218 } 2219 } 2220 } 2221 2222 if (srcp == NULL) { 2223 int e; 2224 struct sockaddr_in6 sin6; 2225 struct route_in6 ro; 2226 2227 /* 2228 * This case matches to multicasts, our anycast, or unicasts 2229 * that we do not own. Select a source address based on the 2230 * source address of the erroneous packet. 2231 */ 2232 bzero(&sin6, sizeof(sin6)); 2233 sin6.sin6_family = AF_INET6; 2234 sin6.sin6_len = sizeof(sin6); 2235 sin6.sin6_addr = ip6->ip6_dst; /* zone ID should be embedded */ 2236 2237 bzero(&ro, sizeof(ro)); 2238 e = in6_selectsrc(&sin6, NULL, NULL, &ro, NULL, &outif, &src); 2239 if (ro.ro_rt) 2240 RTFREE(ro.ro_rt); /* XXX: we could use this */ 2241 if (e) { 2242 char ip6buf[INET6_ADDRSTRLEN]; 2243 nd6log((LOG_DEBUG, 2244 "icmp6_reflect: source can't be determined: " 2245 "dst=%s, error=%d\n", 2246 ip6_sprintf(ip6buf, &sin6.sin6_addr), e)); 2247 goto bad; 2248 } 2249 srcp = &src; 2250 } 2251 2252 ip6->ip6_src = *srcp; 2253 ip6->ip6_flow = 0; 2254 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2255 ip6->ip6_vfc |= IPV6_VERSION; 2256 ip6->ip6_nxt = IPPROTO_ICMPV6; 2257 if (outif) 2258 ip6->ip6_hlim = ND_IFINFO(outif)->chlim; 2259 else if (m->m_pkthdr.rcvif) { 2260 /* XXX: This may not be the outgoing interface */ 2261 ip6->ip6_hlim = ND_IFINFO(m->m_pkthdr.rcvif)->chlim; 2262 } else 2263 ip6->ip6_hlim = V_ip6_defhlim; 2264 2265 icmp6->icmp6_cksum = 0; 2266 icmp6->icmp6_cksum = in6_cksum(m, IPPROTO_ICMPV6, 2267 sizeof(struct ip6_hdr), plen); 2268 2269 /* 2270 * XXX option handling 2271 */ 2272 2273 m->m_flags &= ~(M_BCAST|M_MCAST); 2274 2275 ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL); 2276 if (outif) 2277 icmp6_ifoutstat_inc(outif, type, code); 2278 2279 if (ia != NULL) 2280 ifa_free(&ia->ia_ifa); 2281 return; 2282 2283 bad: 2284 if (ia != NULL) 2285 ifa_free(&ia->ia_ifa); 2286 m_freem(m); 2287 return; 2288 } 2289 2290 void 2291 icmp6_fasttimo(void) 2292 { 2293 2294 mld_fasttimo(); 2295 } 2296 2297 void 2298 icmp6_slowtimo(void) 2299 { 2300 2301 mld_slowtimo(); 2302 } 2303 2304 static const char * 2305 icmp6_redirect_diag(struct in6_addr *src6, struct in6_addr *dst6, 2306 struct in6_addr *tgt6) 2307 { 2308 static char buf[1024]; 2309 char ip6bufs[INET6_ADDRSTRLEN]; 2310 char ip6bufd[INET6_ADDRSTRLEN]; 2311 char ip6buft[INET6_ADDRSTRLEN]; 2312 snprintf(buf, sizeof(buf), "(src=%s dst=%s tgt=%s)", 2313 ip6_sprintf(ip6bufs, src6), ip6_sprintf(ip6bufd, dst6), 2314 ip6_sprintf(ip6buft, tgt6)); 2315 return buf; 2316 } 2317 2318 void 2319 icmp6_redirect_input(struct mbuf *m, int off) 2320 { 2321 struct ifnet *ifp; 2322 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 2323 struct nd_redirect *nd_rd; 2324 int icmp6len = ntohs(ip6->ip6_plen); 2325 char *lladdr = NULL; 2326 int lladdrlen = 0; 2327 struct rtentry *rt = NULL; 2328 int is_router; 2329 int is_onlink; 2330 struct in6_addr src6 = ip6->ip6_src; 2331 struct in6_addr redtgt6; 2332 struct in6_addr reddst6; 2333 union nd_opts ndopts; 2334 char ip6buf[INET6_ADDRSTRLEN]; 2335 2336 M_ASSERTPKTHDR(m); 2337 KASSERT(m->m_pkthdr.rcvif != NULL, ("%s: no rcvif", __func__)); 2338 2339 ifp = m->m_pkthdr.rcvif; 2340 2341 /* XXX if we are router, we don't update route by icmp6 redirect */ 2342 if (V_ip6_forwarding) 2343 goto freeit; 2344 if (!V_icmp6_rediraccept) 2345 goto freeit; 2346 2347 #ifndef PULLDOWN_TEST 2348 IP6_EXTHDR_CHECK(m, off, icmp6len,); 2349 nd_rd = (struct nd_redirect *)((caddr_t)ip6 + off); 2350 #else 2351 IP6_EXTHDR_GET(nd_rd, struct nd_redirect *, m, off, icmp6len); 2352 if (nd_rd == NULL) { 2353 ICMP6STAT_INC(icp6s_tooshort); 2354 return; 2355 } 2356 #endif 2357 redtgt6 = nd_rd->nd_rd_target; 2358 reddst6 = nd_rd->nd_rd_dst; 2359 2360 if (in6_setscope(&redtgt6, m->m_pkthdr.rcvif, NULL) || 2361 in6_setscope(&reddst6, m->m_pkthdr.rcvif, NULL)) { 2362 goto freeit; 2363 } 2364 2365 /* validation */ 2366 if (!IN6_IS_ADDR_LINKLOCAL(&src6)) { 2367 nd6log((LOG_ERR, 2368 "ICMP6 redirect sent from %s rejected; " 2369 "must be from linklocal\n", 2370 ip6_sprintf(ip6buf, &src6))); 2371 goto bad; 2372 } 2373 if (ip6->ip6_hlim != 255) { 2374 nd6log((LOG_ERR, 2375 "ICMP6 redirect sent from %s rejected; " 2376 "hlim=%d (must be 255)\n", 2377 ip6_sprintf(ip6buf, &src6), ip6->ip6_hlim)); 2378 goto bad; 2379 } 2380 { 2381 /* ip6->ip6_src must be equal to gw for icmp6->icmp6_reddst */ 2382 struct sockaddr_in6 sin6; 2383 struct in6_addr *gw6; 2384 2385 bzero(&sin6, sizeof(sin6)); 2386 sin6.sin6_family = AF_INET6; 2387 sin6.sin6_len = sizeof(struct sockaddr_in6); 2388 bcopy(&reddst6, &sin6.sin6_addr, sizeof(reddst6)); 2389 rt = in6_rtalloc1((struct sockaddr *)&sin6, 0, 0UL, RT_DEFAULT_FIB); 2390 if (rt) { 2391 if (rt->rt_gateway == NULL || 2392 rt->rt_gateway->sa_family != AF_INET6) { 2393 RTFREE_LOCKED(rt); 2394 nd6log((LOG_ERR, 2395 "ICMP6 redirect rejected; no route " 2396 "with inet6 gateway found for redirect dst: %s\n", 2397 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2398 goto bad; 2399 } 2400 2401 gw6 = &(((struct sockaddr_in6 *)rt->rt_gateway)->sin6_addr); 2402 if (bcmp(&src6, gw6, sizeof(struct in6_addr)) != 0) { 2403 RTFREE_LOCKED(rt); 2404 nd6log((LOG_ERR, 2405 "ICMP6 redirect rejected; " 2406 "not equal to gw-for-src=%s (must be same): " 2407 "%s\n", 2408 ip6_sprintf(ip6buf, gw6), 2409 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2410 goto bad; 2411 } 2412 } else { 2413 nd6log((LOG_ERR, 2414 "ICMP6 redirect rejected; " 2415 "no route found for redirect dst: %s\n", 2416 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2417 goto bad; 2418 } 2419 RTFREE_LOCKED(rt); 2420 rt = NULL; 2421 } 2422 if (IN6_IS_ADDR_MULTICAST(&reddst6)) { 2423 nd6log((LOG_ERR, 2424 "ICMP6 redirect rejected; " 2425 "redirect dst must be unicast: %s\n", 2426 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2427 goto bad; 2428 } 2429 2430 is_router = is_onlink = 0; 2431 if (IN6_IS_ADDR_LINKLOCAL(&redtgt6)) 2432 is_router = 1; /* router case */ 2433 if (bcmp(&redtgt6, &reddst6, sizeof(redtgt6)) == 0) 2434 is_onlink = 1; /* on-link destination case */ 2435 if (!is_router && !is_onlink) { 2436 nd6log((LOG_ERR, 2437 "ICMP6 redirect rejected; " 2438 "neither router case nor onlink case: %s\n", 2439 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2440 goto bad; 2441 } 2442 /* validation passed */ 2443 2444 icmp6len -= sizeof(*nd_rd); 2445 nd6_option_init(nd_rd + 1, icmp6len, &ndopts); 2446 if (nd6_options(&ndopts) < 0) { 2447 nd6log((LOG_INFO, "%s: invalid ND option, rejected: %s\n", 2448 __func__, icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2449 /* nd6_options have incremented stats */ 2450 goto freeit; 2451 } 2452 2453 if (ndopts.nd_opts_tgt_lladdr) { 2454 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 2455 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 2456 } 2457 2458 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 2459 nd6log((LOG_INFO, "%s: lladdrlen mismatch for %s " 2460 "(if %d, icmp6 packet %d): %s\n", 2461 __func__, ip6_sprintf(ip6buf, &redtgt6), 2462 ifp->if_addrlen, lladdrlen - 2, 2463 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2464 goto bad; 2465 } 2466 2467 /* RFC 2461 8.3 */ 2468 nd6_cache_lladdr(ifp, &redtgt6, lladdr, lladdrlen, ND_REDIRECT, 2469 is_onlink ? ND_REDIRECT_ONLINK : ND_REDIRECT_ROUTER); 2470 2471 if (!is_onlink) { /* better router case. perform rtredirect. */ 2472 /* perform rtredirect */ 2473 struct sockaddr_in6 sdst; 2474 struct sockaddr_in6 sgw; 2475 struct sockaddr_in6 ssrc; 2476 u_int fibnum; 2477 2478 bzero(&sdst, sizeof(sdst)); 2479 bzero(&sgw, sizeof(sgw)); 2480 bzero(&ssrc, sizeof(ssrc)); 2481 sdst.sin6_family = sgw.sin6_family = ssrc.sin6_family = AF_INET6; 2482 sdst.sin6_len = sgw.sin6_len = ssrc.sin6_len = 2483 sizeof(struct sockaddr_in6); 2484 bcopy(&redtgt6, &sgw.sin6_addr, sizeof(struct in6_addr)); 2485 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2486 bcopy(&src6, &ssrc.sin6_addr, sizeof(struct in6_addr)); 2487 for (fibnum = 0; fibnum < rt_numfibs; fibnum++) 2488 in6_rtredirect((struct sockaddr *)&sdst, 2489 (struct sockaddr *)&sgw, (struct sockaddr *)NULL, 2490 RTF_GATEWAY | RTF_HOST, (struct sockaddr *)&ssrc, 2491 fibnum); 2492 } 2493 /* finally update cached route in each socket via pfctlinput */ 2494 { 2495 struct sockaddr_in6 sdst; 2496 2497 bzero(&sdst, sizeof(sdst)); 2498 sdst.sin6_family = AF_INET6; 2499 sdst.sin6_len = sizeof(struct sockaddr_in6); 2500 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2501 pfctlinput(PRC_REDIRECT_HOST, (struct sockaddr *)&sdst); 2502 #ifdef IPSEC 2503 key_sa_routechange((struct sockaddr *)&sdst); 2504 #endif /* IPSEC */ 2505 } 2506 2507 freeit: 2508 m_freem(m); 2509 return; 2510 2511 bad: 2512 ICMP6STAT_INC(icp6s_badredirect); 2513 m_freem(m); 2514 } 2515 2516 void 2517 icmp6_redirect_output(struct mbuf *m0, struct rtentry *rt) 2518 { 2519 struct ifnet *ifp; /* my outgoing interface */ 2520 struct in6_addr *ifp_ll6; 2521 struct in6_addr *router_ll6; 2522 struct ip6_hdr *sip6; /* m0 as struct ip6_hdr */ 2523 struct mbuf *m = NULL; /* newly allocated one */ 2524 struct m_tag *mtag; 2525 struct ip6_hdr *ip6; /* m as struct ip6_hdr */ 2526 struct nd_redirect *nd_rd; 2527 struct llentry *ln = NULL; 2528 size_t maxlen; 2529 u_char *p; 2530 struct ifnet *outif = NULL; 2531 struct sockaddr_in6 src_sa; 2532 2533 icmp6_errcount(&V_icmp6stat.icp6s_outerrhist, ND_REDIRECT, 0); 2534 2535 /* if we are not router, we don't send icmp6 redirect */ 2536 if (!V_ip6_forwarding) 2537 goto fail; 2538 2539 /* sanity check */ 2540 if (!m0 || !rt || !(rt->rt_flags & RTF_UP) || !(ifp = rt->rt_ifp)) 2541 goto fail; 2542 2543 /* 2544 * Address check: 2545 * the source address must identify a neighbor, and 2546 * the destination address must not be a multicast address 2547 * [RFC 2461, sec 8.2] 2548 */ 2549 sip6 = mtod(m0, struct ip6_hdr *); 2550 bzero(&src_sa, sizeof(src_sa)); 2551 src_sa.sin6_family = AF_INET6; 2552 src_sa.sin6_len = sizeof(src_sa); 2553 src_sa.sin6_addr = sip6->ip6_src; 2554 if (nd6_is_addr_neighbor(&src_sa, ifp) == 0) 2555 goto fail; 2556 if (IN6_IS_ADDR_MULTICAST(&sip6->ip6_dst)) 2557 goto fail; /* what should we do here? */ 2558 2559 /* rate limit */ 2560 if (icmp6_ratelimit(&sip6->ip6_src, ND_REDIRECT, 0)) 2561 goto fail; 2562 2563 /* 2564 * Since we are going to append up to 1280 bytes (= IPV6_MMTU), 2565 * we almost always ask for an mbuf cluster for simplicity. 2566 * (MHLEN < IPV6_MMTU is almost always true) 2567 */ 2568 #if IPV6_MMTU >= MCLBYTES 2569 # error assumption failed about IPV6_MMTU and MCLBYTES 2570 #endif 2571 m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR); 2572 if (m == NULL) 2573 goto fail; 2574 M_SETFIB(m, rt->rt_fibnum); 2575 maxlen = M_TRAILINGSPACE(m); 2576 maxlen = min(IPV6_MMTU, maxlen); 2577 /* just for safety */ 2578 if (maxlen < sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) + 2579 ((sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7)) { 2580 goto fail; 2581 } 2582 2583 { 2584 /* get ip6 linklocal address for ifp(my outgoing interface). */ 2585 struct in6_ifaddr *ia; 2586 if ((ia = in6ifa_ifpforlinklocal(ifp, 2587 IN6_IFF_NOTREADY| 2588 IN6_IFF_ANYCAST)) == NULL) 2589 goto fail; 2590 ifp_ll6 = &ia->ia_addr.sin6_addr; 2591 /* XXXRW: reference released prematurely. */ 2592 ifa_free(&ia->ia_ifa); 2593 } 2594 2595 /* get ip6 linklocal address for the router. */ 2596 if (rt->rt_gateway && (rt->rt_flags & RTF_GATEWAY)) { 2597 struct sockaddr_in6 *sin6; 2598 sin6 = (struct sockaddr_in6 *)rt->rt_gateway; 2599 router_ll6 = &sin6->sin6_addr; 2600 if (!IN6_IS_ADDR_LINKLOCAL(router_ll6)) 2601 router_ll6 = (struct in6_addr *)NULL; 2602 } else 2603 router_ll6 = (struct in6_addr *)NULL; 2604 2605 /* ip6 */ 2606 ip6 = mtod(m, struct ip6_hdr *); 2607 ip6->ip6_flow = 0; 2608 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2609 ip6->ip6_vfc |= IPV6_VERSION; 2610 /* ip6->ip6_plen will be set later */ 2611 ip6->ip6_nxt = IPPROTO_ICMPV6; 2612 ip6->ip6_hlim = 255; 2613 /* ip6->ip6_src must be linklocal addr for my outgoing if. */ 2614 bcopy(ifp_ll6, &ip6->ip6_src, sizeof(struct in6_addr)); 2615 bcopy(&sip6->ip6_src, &ip6->ip6_dst, sizeof(struct in6_addr)); 2616 2617 /* ND Redirect */ 2618 nd_rd = (struct nd_redirect *)(ip6 + 1); 2619 nd_rd->nd_rd_type = ND_REDIRECT; 2620 nd_rd->nd_rd_code = 0; 2621 nd_rd->nd_rd_reserved = 0; 2622 if (rt->rt_flags & RTF_GATEWAY) { 2623 /* 2624 * nd_rd->nd_rd_target must be a link-local address in 2625 * better router cases. 2626 */ 2627 if (!router_ll6) 2628 goto fail; 2629 bcopy(router_ll6, &nd_rd->nd_rd_target, 2630 sizeof(nd_rd->nd_rd_target)); 2631 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2632 sizeof(nd_rd->nd_rd_dst)); 2633 } else { 2634 /* make sure redtgt == reddst */ 2635 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_target, 2636 sizeof(nd_rd->nd_rd_target)); 2637 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2638 sizeof(nd_rd->nd_rd_dst)); 2639 } 2640 2641 p = (u_char *)(nd_rd + 1); 2642 2643 if (!router_ll6) 2644 goto nolladdropt; 2645 2646 { 2647 /* target lladdr option */ 2648 int len; 2649 struct nd_opt_hdr *nd_opt; 2650 char *lladdr; 2651 2652 IF_AFDATA_RLOCK(ifp); 2653 ln = nd6_lookup(router_ll6, 0, ifp); 2654 IF_AFDATA_RUNLOCK(ifp); 2655 if (ln == NULL) 2656 goto nolladdropt; 2657 2658 len = sizeof(*nd_opt) + ifp->if_addrlen; 2659 len = (len + 7) & ~7; /* round by 8 */ 2660 /* safety check */ 2661 if (len + (p - (u_char *)ip6) > maxlen) 2662 goto nolladdropt; 2663 2664 if (ln->la_flags & LLE_VALID) { 2665 nd_opt = (struct nd_opt_hdr *)p; 2666 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 2667 nd_opt->nd_opt_len = len >> 3; 2668 lladdr = (char *)(nd_opt + 1); 2669 bcopy(&ln->ll_addr, lladdr, ifp->if_addrlen); 2670 p += len; 2671 } 2672 } 2673 nolladdropt: 2674 if (ln != NULL) 2675 LLE_RUNLOCK(ln); 2676 2677 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2678 2679 /* just to be safe */ 2680 #ifdef M_DECRYPTED /*not openbsd*/ 2681 if (m0->m_flags & M_DECRYPTED) 2682 goto noredhdropt; 2683 #endif 2684 if (p - (u_char *)ip6 > maxlen) 2685 goto noredhdropt; 2686 2687 { 2688 /* redirected header option */ 2689 int len; 2690 struct nd_opt_rd_hdr *nd_opt_rh; 2691 2692 /* 2693 * compute the maximum size for icmp6 redirect header option. 2694 * XXX room for auth header? 2695 */ 2696 len = maxlen - (p - (u_char *)ip6); 2697 len &= ~7; 2698 2699 /* This is just for simplicity. */ 2700 if (m0->m_pkthdr.len != m0->m_len) { 2701 if (m0->m_next) { 2702 m_freem(m0->m_next); 2703 m0->m_next = NULL; 2704 } 2705 m0->m_pkthdr.len = m0->m_len; 2706 } 2707 2708 /* 2709 * Redirected header option spec (RFC2461 4.6.3) talks nothing 2710 * about padding/truncate rule for the original IP packet. 2711 * From the discussion on IPv6imp in Feb 1999, 2712 * the consensus was: 2713 * - "attach as much as possible" is the goal 2714 * - pad if not aligned (original size can be guessed by 2715 * original ip6 header) 2716 * Following code adds the padding if it is simple enough, 2717 * and truncates if not. 2718 */ 2719 if (m0->m_next || m0->m_pkthdr.len != m0->m_len) 2720 panic("assumption failed in %s:%d", __FILE__, 2721 __LINE__); 2722 2723 if (len - sizeof(*nd_opt_rh) < m0->m_pkthdr.len) { 2724 /* not enough room, truncate */ 2725 m0->m_pkthdr.len = m0->m_len = len - 2726 sizeof(*nd_opt_rh); 2727 } else { 2728 /* enough room, pad or truncate */ 2729 size_t extra; 2730 2731 extra = m0->m_pkthdr.len % 8; 2732 if (extra) { 2733 /* pad if easy enough, truncate if not */ 2734 if (8 - extra <= M_TRAILINGSPACE(m0)) { 2735 /* pad */ 2736 m0->m_len += (8 - extra); 2737 m0->m_pkthdr.len += (8 - extra); 2738 } else { 2739 /* truncate */ 2740 m0->m_pkthdr.len -= extra; 2741 m0->m_len -= extra; 2742 } 2743 } 2744 len = m0->m_pkthdr.len + sizeof(*nd_opt_rh); 2745 m0->m_pkthdr.len = m0->m_len = len - 2746 sizeof(*nd_opt_rh); 2747 } 2748 2749 nd_opt_rh = (struct nd_opt_rd_hdr *)p; 2750 bzero(nd_opt_rh, sizeof(*nd_opt_rh)); 2751 nd_opt_rh->nd_opt_rh_type = ND_OPT_REDIRECTED_HEADER; 2752 nd_opt_rh->nd_opt_rh_len = len >> 3; 2753 p += sizeof(*nd_opt_rh); 2754 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2755 2756 /* connect m0 to m */ 2757 m_tag_delete_chain(m0, NULL); 2758 m0->m_flags &= ~M_PKTHDR; 2759 m->m_next = m0; 2760 m->m_pkthdr.len = m->m_len + m0->m_len; 2761 m0 = NULL; 2762 } 2763 noredhdropt:; 2764 if (m0) { 2765 m_freem(m0); 2766 m0 = NULL; 2767 } 2768 2769 /* XXX: clear embedded link IDs in the inner header */ 2770 in6_clearscope(&sip6->ip6_src); 2771 in6_clearscope(&sip6->ip6_dst); 2772 in6_clearscope(&nd_rd->nd_rd_target); 2773 in6_clearscope(&nd_rd->nd_rd_dst); 2774 2775 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr)); 2776 2777 nd_rd->nd_rd_cksum = 0; 2778 nd_rd->nd_rd_cksum = in6_cksum(m, IPPROTO_ICMPV6, 2779 sizeof(*ip6), ntohs(ip6->ip6_plen)); 2780 2781 if (send_sendso_input_hook != NULL) { 2782 mtag = m_tag_get(PACKET_TAG_ND_OUTGOING, sizeof(unsigned short), 2783 M_NOWAIT); 2784 if (mtag == NULL) 2785 goto fail; 2786 *(unsigned short *)(mtag + 1) = nd_rd->nd_rd_type; 2787 m_tag_prepend(m, mtag); 2788 } 2789 2790 /* send the packet to outside... */ 2791 ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL); 2792 if (outif) { 2793 icmp6_ifstat_inc(outif, ifs6_out_msg); 2794 icmp6_ifstat_inc(outif, ifs6_out_redirect); 2795 } 2796 ICMP6STAT_INC(icp6s_outhist[ND_REDIRECT]); 2797 2798 return; 2799 2800 fail: 2801 if (m) 2802 m_freem(m); 2803 if (m0) 2804 m_freem(m0); 2805 } 2806 2807 /* 2808 * ICMPv6 socket option processing. 2809 */ 2810 int 2811 icmp6_ctloutput(struct socket *so, struct sockopt *sopt) 2812 { 2813 int error = 0; 2814 int optlen; 2815 struct inpcb *inp = sotoinpcb(so); 2816 int level, op, optname; 2817 2818 if (sopt) { 2819 level = sopt->sopt_level; 2820 op = sopt->sopt_dir; 2821 optname = sopt->sopt_name; 2822 optlen = sopt->sopt_valsize; 2823 } else 2824 level = op = optname = optlen = 0; 2825 2826 if (level != IPPROTO_ICMPV6) { 2827 return EINVAL; 2828 } 2829 2830 switch (op) { 2831 case PRCO_SETOPT: 2832 switch (optname) { 2833 case ICMP6_FILTER: 2834 { 2835 struct icmp6_filter ic6f; 2836 2837 if (optlen != sizeof(ic6f)) { 2838 error = EMSGSIZE; 2839 break; 2840 } 2841 error = sooptcopyin(sopt, &ic6f, optlen, optlen); 2842 if (error == 0) { 2843 INP_WLOCK(inp); 2844 *inp->in6p_icmp6filt = ic6f; 2845 INP_WUNLOCK(inp); 2846 } 2847 break; 2848 } 2849 2850 default: 2851 error = ENOPROTOOPT; 2852 break; 2853 } 2854 break; 2855 2856 case PRCO_GETOPT: 2857 switch (optname) { 2858 case ICMP6_FILTER: 2859 { 2860 struct icmp6_filter ic6f; 2861 2862 INP_RLOCK(inp); 2863 ic6f = *inp->in6p_icmp6filt; 2864 INP_RUNLOCK(inp); 2865 error = sooptcopyout(sopt, &ic6f, sizeof(ic6f)); 2866 break; 2867 } 2868 2869 default: 2870 error = ENOPROTOOPT; 2871 break; 2872 } 2873 break; 2874 } 2875 2876 return (error); 2877 } 2878 2879 /* 2880 * Perform rate limit check. 2881 * Returns 0 if it is okay to send the icmp6 packet. 2882 * Returns 1 if the router SHOULD NOT send this icmp6 packet due to rate 2883 * limitation. 2884 * 2885 * XXX per-destination/type check necessary? 2886 * 2887 * dst - not used at this moment 2888 * type - not used at this moment 2889 * code - not used at this moment 2890 */ 2891 static int 2892 icmp6_ratelimit(const struct in6_addr *dst, const int type, 2893 const int code) 2894 { 2895 int ret; 2896 2897 ret = 0; /* okay to send */ 2898 2899 /* PPS limit */ 2900 if (!ppsratecheck(&V_icmp6errppslim_last, &V_icmp6errpps_count, 2901 V_icmp6errppslim)) { 2902 /* The packet is subject to rate limit */ 2903 ret++; 2904 } 2905 2906 return ret; 2907 } 2908