icmp6.c revision 275828
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: stable/10/sys/netinet6/icmp6.c 275828 2014-12-16 11:53:45Z ae $"); 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 115extern struct domain inet6domain; 116 117VNET_PCPUSTAT_DEFINE(struct icmp6stat, icmp6stat); 118VNET_PCPUSTAT_SYSINIT(icmp6stat); 119 120#ifdef VIMAGE 121VNET_PCPUSTAT_SYSUNINIT(icmp6stat); 122#endif /* VIMAGE */ 123 124VNET_DECLARE(struct inpcbinfo, ripcbinfo); 125VNET_DECLARE(struct inpcbhead, ripcb); 126VNET_DECLARE(int, icmp6errppslim); 127static VNET_DEFINE(int, icmp6errpps_count) = 0; 128static VNET_DEFINE(struct timeval, icmp6errppslim_last); 129VNET_DECLARE(int, icmp6_nodeinfo); 130 131#define V_ripcbinfo VNET(ripcbinfo) 132#define V_ripcb VNET(ripcb) 133#define V_icmp6errppslim VNET(icmp6errppslim) 134#define V_icmp6errpps_count VNET(icmp6errpps_count) 135#define V_icmp6errppslim_last VNET(icmp6errppslim_last) 136#define V_icmp6_nodeinfo VNET(icmp6_nodeinfo) 137 138static void icmp6_errcount(int, int); 139static int icmp6_rip6_input(struct mbuf **, int); 140static int icmp6_ratelimit(const struct in6_addr *, const int, const int); 141static const char *icmp6_redirect_diag(struct in6_addr *, 142 struct in6_addr *, struct in6_addr *); 143static struct mbuf *ni6_input(struct mbuf *, int); 144static struct mbuf *ni6_nametodns(const char *, int, int); 145static int ni6_dnsmatch(const char *, int, const char *, int); 146static int ni6_addrs(struct icmp6_nodeinfo *, struct mbuf *, 147 struct ifnet **, struct in6_addr *); 148static int ni6_store_addrs(struct icmp6_nodeinfo *, struct icmp6_nodeinfo *, 149 struct ifnet *, int); 150static int icmp6_notify_error(struct mbuf **, int, int, int); 151 152/* 153 * Kernel module interface for updating icmp6stat. The argument is an index 154 * into icmp6stat treated as an array of u_quad_t. While this encodes the 155 * general layout of icmp6stat into the caller, it doesn't encode its 156 * location, so that future changes to add, for example, per-CPU stats 157 * support won't cause binary compatibility problems for kernel modules. 158 */ 159void 160kmod_icmp6stat_inc(int statnum) 161{ 162 163 counter_u64_add(VNET(icmp6stat)[statnum], 1); 164} 165 166static void 167icmp6_errcount(int type, int code) 168{ 169 switch (type) { 170 case ICMP6_DST_UNREACH: 171 switch (code) { 172 case ICMP6_DST_UNREACH_NOROUTE: 173 ICMP6STAT_INC(icp6s_odst_unreach_noroute); 174 return; 175 case ICMP6_DST_UNREACH_ADMIN: 176 ICMP6STAT_INC(icp6s_odst_unreach_admin); 177 return; 178 case ICMP6_DST_UNREACH_BEYONDSCOPE: 179 ICMP6STAT_INC(icp6s_odst_unreach_beyondscope); 180 return; 181 case ICMP6_DST_UNREACH_ADDR: 182 ICMP6STAT_INC(icp6s_odst_unreach_addr); 183 return; 184 case ICMP6_DST_UNREACH_NOPORT: 185 ICMP6STAT_INC(icp6s_odst_unreach_noport); 186 return; 187 } 188 break; 189 case ICMP6_PACKET_TOO_BIG: 190 ICMP6STAT_INC(icp6s_opacket_too_big); 191 return; 192 case ICMP6_TIME_EXCEEDED: 193 switch (code) { 194 case ICMP6_TIME_EXCEED_TRANSIT: 195 ICMP6STAT_INC(icp6s_otime_exceed_transit); 196 return; 197 case ICMP6_TIME_EXCEED_REASSEMBLY: 198 ICMP6STAT_INC(icp6s_otime_exceed_reassembly); 199 return; 200 } 201 break; 202 case ICMP6_PARAM_PROB: 203 switch (code) { 204 case ICMP6_PARAMPROB_HEADER: 205 ICMP6STAT_INC(icp6s_oparamprob_header); 206 return; 207 case ICMP6_PARAMPROB_NEXTHEADER: 208 ICMP6STAT_INC(icp6s_oparamprob_nextheader); 209 return; 210 case ICMP6_PARAMPROB_OPTION: 211 ICMP6STAT_INC(icp6s_oparamprob_option); 212 return; 213 } 214 break; 215 case ND_REDIRECT: 216 ICMP6STAT_INC(icp6s_oredirect); 217 return; 218 } 219 ICMP6STAT_INC(icp6s_ounknown); 220} 221 222/* 223 * A wrapper function for icmp6_error() necessary when the erroneous packet 224 * may not contain enough scope zone information. 225 */ 226void 227icmp6_error2(struct mbuf *m, int type, int code, int param, 228 struct ifnet *ifp) 229{ 230 struct ip6_hdr *ip6; 231 232 if (ifp == NULL) 233 return; 234 235#ifndef PULLDOWN_TEST 236 IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), ); 237#else 238 if (m->m_len < sizeof(struct ip6_hdr)) { 239 m = m_pullup(m, sizeof(struct ip6_hdr)); 240 if (m == NULL) 241 return; 242 } 243#endif 244 245 ip6 = mtod(m, struct ip6_hdr *); 246 247 if (in6_setscope(&ip6->ip6_src, ifp, NULL) != 0) 248 return; 249 if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0) 250 return; 251 252 icmp6_error(m, type, code, param); 253} 254 255/* 256 * Generate an error packet of type error in response to bad IP6 packet. 257 */ 258void 259icmp6_error(struct mbuf *m, int type, int code, int param) 260{ 261 struct ip6_hdr *oip6, *nip6; 262 struct icmp6_hdr *icmp6; 263 u_int preplen; 264 int off; 265 int nxt; 266 267 ICMP6STAT_INC(icp6s_error); 268 269 /* count per-type-code statistics */ 270 icmp6_errcount(type, code); 271 272#ifdef M_DECRYPTED /*not openbsd*/ 273 if (m->m_flags & M_DECRYPTED) { 274 ICMP6STAT_INC(icp6s_canterror); 275 goto freeit; 276 } 277#endif 278 279#ifndef PULLDOWN_TEST 280 IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), ); 281#else 282 if (m->m_len < sizeof(struct ip6_hdr)) { 283 m = m_pullup(m, sizeof(struct ip6_hdr)); 284 if (m == NULL) 285 return; 286 } 287#endif 288 oip6 = mtod(m, struct ip6_hdr *); 289 290 /* 291 * If the destination address of the erroneous packet is a multicast 292 * address, or the packet was sent using link-layer multicast, 293 * we should basically suppress sending an error (RFC 2463, Section 294 * 2.4). 295 * We have two exceptions (the item e.2 in that section): 296 * - the Packet Too Big message can be sent for path MTU discovery. 297 * - the Parameter Problem Message that can be allowed an icmp6 error 298 * in the option type field. This check has been done in 299 * ip6_unknown_opt(), so we can just check the type and code. 300 */ 301 if ((m->m_flags & (M_BCAST|M_MCAST) || 302 IN6_IS_ADDR_MULTICAST(&oip6->ip6_dst)) && 303 (type != ICMP6_PACKET_TOO_BIG && 304 (type != ICMP6_PARAM_PROB || 305 code != ICMP6_PARAMPROB_OPTION))) 306 goto freeit; 307 308 /* 309 * RFC 2463, 2.4 (e.5): source address check. 310 * XXX: the case of anycast source? 311 */ 312 if (IN6_IS_ADDR_UNSPECIFIED(&oip6->ip6_src) || 313 IN6_IS_ADDR_MULTICAST(&oip6->ip6_src)) 314 goto freeit; 315 316 /* 317 * If we are about to send ICMPv6 against ICMPv6 error/redirect, 318 * don't do it. 319 */ 320 nxt = -1; 321 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); 322 if (off >= 0 && nxt == IPPROTO_ICMPV6) { 323 struct icmp6_hdr *icp; 324 325#ifndef PULLDOWN_TEST 326 IP6_EXTHDR_CHECK(m, 0, off + sizeof(struct icmp6_hdr), ); 327 icp = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 328#else 329 IP6_EXTHDR_GET(icp, struct icmp6_hdr *, m, off, 330 sizeof(*icp)); 331 if (icp == NULL) { 332 ICMP6STAT_INC(icp6s_tooshort); 333 return; 334 } 335#endif 336 if (icp->icmp6_type < ICMP6_ECHO_REQUEST || 337 icp->icmp6_type == ND_REDIRECT) { 338 /* 339 * ICMPv6 error 340 * Special case: for redirect (which is 341 * informational) we must not send icmp6 error. 342 */ 343 ICMP6STAT_INC(icp6s_canterror); 344 goto freeit; 345 } else { 346 /* ICMPv6 informational - send the error */ 347 } 348 } else { 349 /* non-ICMPv6 - send the error */ 350 } 351 352 oip6 = mtod(m, struct ip6_hdr *); /* adjust pointer */ 353 354 /* Finally, do rate limitation check. */ 355 if (icmp6_ratelimit(&oip6->ip6_src, type, code)) { 356 ICMP6STAT_INC(icp6s_toofreq); 357 goto freeit; 358 } 359 360 /* 361 * OK, ICMP6 can be generated. 362 */ 363 364 if (m->m_pkthdr.len >= ICMPV6_PLD_MAXLEN) 365 m_adj(m, ICMPV6_PLD_MAXLEN - m->m_pkthdr.len); 366 367 preplen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 368 M_PREPEND(m, preplen, M_NOWAIT); /* FIB is also copied over. */ 369 if (m == NULL) { 370 nd6log((LOG_DEBUG, "ENOBUFS in icmp6_error %d\n", __LINE__)); 371 return; 372 } 373 374 nip6 = mtod(m, struct ip6_hdr *); 375 nip6->ip6_src = oip6->ip6_src; 376 nip6->ip6_dst = oip6->ip6_dst; 377 378 in6_clearscope(&oip6->ip6_src); 379 in6_clearscope(&oip6->ip6_dst); 380 381 icmp6 = (struct icmp6_hdr *)(nip6 + 1); 382 icmp6->icmp6_type = type; 383 icmp6->icmp6_code = code; 384 icmp6->icmp6_pptr = htonl((u_int32_t)param); 385 386 /* 387 * icmp6_reflect() is designed to be in the input path. 388 * icmp6_error() can be called from both input and output path, 389 * and if we are in output path rcvif could contain bogus value. 390 * clear m->m_pkthdr.rcvif for safety, we should have enough scope 391 * information in ip header (nip6). 392 */ 393 m->m_pkthdr.rcvif = NULL; 394 395 ICMP6STAT_INC(icp6s_outhist[type]); 396 icmp6_reflect(m, sizeof(struct ip6_hdr)); /* header order: IPv6 - ICMPv6 */ 397 398 return; 399 400 freeit: 401 /* 402 * If we can't tell whether or not we can generate ICMP6, free it. 403 */ 404 m_freem(m); 405} 406 407/* 408 * Process a received ICMP6 message. 409 */ 410int 411icmp6_input(struct mbuf **mp, int *offp, int proto) 412{ 413 struct mbuf *m = *mp, *n; 414 struct ifnet *ifp; 415 struct ip6_hdr *ip6, *nip6; 416 struct icmp6_hdr *icmp6, *nicmp6; 417 int off = *offp; 418 int icmp6len = m->m_pkthdr.len - *offp; 419 int code, sum, noff; 420 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 421 int ip6len, error; 422 423 ifp = m->m_pkthdr.rcvif; 424 425#ifndef PULLDOWN_TEST 426 IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_hdr), IPPROTO_DONE); 427 /* m might change if M_LOOP. So, call mtod after this */ 428#endif 429 430 /* 431 * Locate icmp6 structure in mbuf, and check 432 * that not corrupted and of at least minimum length 433 */ 434 435 ip6 = mtod(m, struct ip6_hdr *); 436 ip6len = sizeof(struct ip6_hdr) + ntohs(ip6->ip6_plen); 437 if (icmp6len < sizeof(struct icmp6_hdr)) { 438 ICMP6STAT_INC(icp6s_tooshort); 439 goto freeit; 440 } 441 442 /* 443 * Check multicast group membership. 444 * Note: SSM filters are not applied for ICMPv6 traffic. 445 */ 446 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 447 struct in6_multi *inm; 448 449 inm = in6m_lookup(ifp, &ip6->ip6_dst); 450 if (inm == NULL) { 451 IP6STAT_INC(ip6s_notmember); 452 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 453 goto freeit; 454 } 455 } 456 457 /* 458 * calculate the checksum 459 */ 460#ifndef PULLDOWN_TEST 461 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off); 462#else 463 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 464 if (icmp6 == NULL) { 465 ICMP6STAT_INC(icp6s_tooshort); 466 return IPPROTO_DONE; 467 } 468#endif 469 code = icmp6->icmp6_code; 470 471 if ((sum = in6_cksum(m, IPPROTO_ICMPV6, off, icmp6len)) != 0) { 472 nd6log((LOG_ERR, 473 "ICMP6 checksum error(%d|%x) %s\n", 474 icmp6->icmp6_type, sum, 475 ip6_sprintf(ip6bufs, &ip6->ip6_src))); 476 ICMP6STAT_INC(icp6s_checksum); 477 goto freeit; 478 } 479 480 if (faithprefix_p != NULL && (*faithprefix_p)(&ip6->ip6_dst)) { 481 /* 482 * Deliver very specific ICMP6 type only. 483 * This is important to deliver TOOBIG. Otherwise PMTUD 484 * will not work. 485 */ 486 switch (icmp6->icmp6_type) { 487 case ICMP6_DST_UNREACH: 488 case ICMP6_PACKET_TOO_BIG: 489 case ICMP6_TIME_EXCEEDED: 490 break; 491 default: 492 goto freeit; 493 } 494 } 495 496 ICMP6STAT_INC(icp6s_inhist[icmp6->icmp6_type]); 497 icmp6_ifstat_inc(ifp, ifs6_in_msg); 498 if (icmp6->icmp6_type < ICMP6_INFOMSG_MASK) 499 icmp6_ifstat_inc(ifp, ifs6_in_error); 500 501 switch (icmp6->icmp6_type) { 502 case ICMP6_DST_UNREACH: 503 icmp6_ifstat_inc(ifp, ifs6_in_dstunreach); 504 switch (code) { 505 case ICMP6_DST_UNREACH_NOROUTE: 506 code = PRC_UNREACH_NET; 507 break; 508 case ICMP6_DST_UNREACH_ADMIN: 509 icmp6_ifstat_inc(ifp, ifs6_in_adminprohib); 510 code = PRC_UNREACH_PROTOCOL; /* is this a good code? */ 511 break; 512 case ICMP6_DST_UNREACH_ADDR: 513 code = PRC_HOSTDEAD; 514 break; 515 case ICMP6_DST_UNREACH_BEYONDSCOPE: 516 /* I mean "source address was incorrect." */ 517 code = PRC_PARAMPROB; 518 break; 519 case ICMP6_DST_UNREACH_NOPORT: 520 code = PRC_UNREACH_PORT; 521 break; 522 default: 523 goto badcode; 524 } 525 goto deliver; 526 break; 527 528 case ICMP6_PACKET_TOO_BIG: 529 icmp6_ifstat_inc(ifp, ifs6_in_pkttoobig); 530 531 /* validation is made in icmp6_mtudisc_update */ 532 533 code = PRC_MSGSIZE; 534 535 /* 536 * Updating the path MTU will be done after examining 537 * intermediate extension headers. 538 */ 539 goto deliver; 540 break; 541 542 case ICMP6_TIME_EXCEEDED: 543 icmp6_ifstat_inc(ifp, ifs6_in_timeexceed); 544 switch (code) { 545 case ICMP6_TIME_EXCEED_TRANSIT: 546 code = PRC_TIMXCEED_INTRANS; 547 break; 548 case ICMP6_TIME_EXCEED_REASSEMBLY: 549 code = PRC_TIMXCEED_REASS; 550 break; 551 default: 552 goto badcode; 553 } 554 goto deliver; 555 break; 556 557 case ICMP6_PARAM_PROB: 558 icmp6_ifstat_inc(ifp, ifs6_in_paramprob); 559 switch (code) { 560 case ICMP6_PARAMPROB_NEXTHEADER: 561 code = PRC_UNREACH_PROTOCOL; 562 break; 563 case ICMP6_PARAMPROB_HEADER: 564 case ICMP6_PARAMPROB_OPTION: 565 code = PRC_PARAMPROB; 566 break; 567 default: 568 goto badcode; 569 } 570 goto deliver; 571 break; 572 573 case ICMP6_ECHO_REQUEST: 574 icmp6_ifstat_inc(ifp, ifs6_in_echo); 575 if (code != 0) 576 goto badcode; 577 if ((n = m_copy(m, 0, M_COPYALL)) == NULL) { 578 /* Give up remote */ 579 break; 580 } 581 if ((n->m_flags & M_EXT) != 0 582 || n->m_len < off + sizeof(struct icmp6_hdr)) { 583 struct mbuf *n0 = n; 584 int n0len; 585 586 CTASSERT(sizeof(*nip6) + sizeof(*nicmp6) <= MHLEN); 587 n = m_gethdr(M_NOWAIT, n0->m_type); 588 if (n == NULL) { 589 /* Give up remote */ 590 m_freem(n0); 591 break; 592 } 593 594 m_move_pkthdr(n, n0); /* FIB copied. */ 595 n0len = n0->m_pkthdr.len; /* save for use below */ 596 /* 597 * Copy IPv6 and ICMPv6 only. 598 */ 599 nip6 = mtod(n, struct ip6_hdr *); 600 bcopy(ip6, nip6, sizeof(struct ip6_hdr)); 601 nicmp6 = (struct icmp6_hdr *)(nip6 + 1); 602 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr)); 603 noff = sizeof(struct ip6_hdr); 604 /* new mbuf contains only ipv6+icmpv6 headers */ 605 n->m_len = noff + sizeof(struct icmp6_hdr); 606 /* 607 * Adjust mbuf. ip6_plen will be adjusted in 608 * ip6_output(). 609 */ 610 m_adj(n0, off + sizeof(struct icmp6_hdr)); 611 /* recalculate complete packet size */ 612 n->m_pkthdr.len = n0len + (noff - off); 613 n->m_next = n0; 614 } else { 615 nip6 = mtod(n, struct ip6_hdr *); 616 IP6_EXTHDR_GET(nicmp6, struct icmp6_hdr *, n, off, 617 sizeof(*nicmp6)); 618 noff = off; 619 } 620 nicmp6->icmp6_type = ICMP6_ECHO_REPLY; 621 nicmp6->icmp6_code = 0; 622 if (n) { 623 ICMP6STAT_INC(icp6s_reflect); 624 ICMP6STAT_INC(icp6s_outhist[ICMP6_ECHO_REPLY]); 625 icmp6_reflect(n, noff); 626 } 627 break; 628 629 case ICMP6_ECHO_REPLY: 630 icmp6_ifstat_inc(ifp, ifs6_in_echoreply); 631 if (code != 0) 632 goto badcode; 633 break; 634 635 case MLD_LISTENER_QUERY: 636 case MLD_LISTENER_REPORT: 637 case MLD_LISTENER_DONE: 638 case MLDV2_LISTENER_REPORT: 639 /* 640 * Drop MLD traffic which is not link-local, has a hop limit 641 * of greater than 1 hop, or which does not have the 642 * IPv6 HBH Router Alert option. 643 * As IPv6 HBH options are stripped in ip6_input() we must 644 * check an mbuf header flag. 645 * XXX Should we also sanity check that these messages 646 * were directed to a link-local multicast prefix? 647 */ 648 if ((ip6->ip6_hlim != 1) || (m->m_flags & M_RTALERT_MLD) == 0) 649 goto freeit; 650 if (mld_input(m, off, icmp6len) != 0) 651 return (IPPROTO_DONE); 652 /* m stays. */ 653 break; 654 655 case ICMP6_WRUREQUEST: /* ICMP6_FQDN_QUERY */ 656 { 657 enum { WRU, FQDN } mode; 658 659 if (!V_icmp6_nodeinfo) 660 break; 661 662 if (icmp6len == sizeof(struct icmp6_hdr) + 4) 663 mode = WRU; 664 else if (icmp6len >= sizeof(struct icmp6_nodeinfo)) 665 mode = FQDN; 666 else 667 goto badlen; 668 669 if (mode == FQDN) { 670#ifndef PULLDOWN_TEST 671 IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_nodeinfo), 672 IPPROTO_DONE); 673#endif 674 n = m_copy(m, 0, M_COPYALL); 675 if (n) 676 n = ni6_input(n, off); 677 /* XXX meaningless if n == NULL */ 678 noff = sizeof(struct ip6_hdr); 679 } else { 680 struct prison *pr; 681 u_char *p; 682 int maxhlen, hlen; 683 684 /* 685 * XXX: this combination of flags is pointless, 686 * but should we keep this for compatibility? 687 */ 688 if ((V_icmp6_nodeinfo & 5) != 5) 689 break; 690 691 if (code != 0) 692 goto badcode; 693 694 CTASSERT(sizeof(*nip6) + sizeof(*nicmp6) + 4 <= MHLEN); 695 n = m_gethdr(M_NOWAIT, m->m_type); 696 if (n == NULL) { 697 /* Give up remote */ 698 break; 699 } 700 if (!m_dup_pkthdr(n, m, M_NOWAIT)) { 701 /* 702 * Previous code did a blind M_COPY_PKTHDR 703 * and said "just for rcvif". If true, then 704 * we could tolerate the dup failing (due to 705 * the deep copy of the tag chain). For now 706 * be conservative and just fail. 707 */ 708 m_free(n); 709 n = NULL; 710 } 711 maxhlen = M_TRAILINGSPACE(n) - 712 (sizeof(*nip6) + sizeof(*nicmp6) + 4); 713 pr = curthread->td_ucred->cr_prison; 714 mtx_lock(&pr->pr_mtx); 715 hlen = strlen(pr->pr_hostname); 716 if (maxhlen > hlen) 717 maxhlen = hlen; 718 /* 719 * Copy IPv6 and ICMPv6 only. 720 */ 721 nip6 = mtod(n, struct ip6_hdr *); 722 bcopy(ip6, nip6, sizeof(struct ip6_hdr)); 723 nicmp6 = (struct icmp6_hdr *)(nip6 + 1); 724 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr)); 725 p = (u_char *)(nicmp6 + 1); 726 bzero(p, 4); 727 /* meaningless TTL */ 728 bcopy(pr->pr_hostname, p + 4, maxhlen); 729 mtx_unlock(&pr->pr_mtx); 730 noff = sizeof(struct ip6_hdr); 731 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) + 732 sizeof(struct icmp6_hdr) + 4 + maxhlen; 733 nicmp6->icmp6_type = ICMP6_WRUREPLY; 734 nicmp6->icmp6_code = 0; 735 } 736 if (n) { 737 ICMP6STAT_INC(icp6s_reflect); 738 ICMP6STAT_INC(icp6s_outhist[ICMP6_WRUREPLY]); 739 icmp6_reflect(n, noff); 740 } 741 break; 742 } 743 744 case ICMP6_WRUREPLY: 745 if (code != 0) 746 goto badcode; 747 break; 748 749 case ND_ROUTER_SOLICIT: 750 icmp6_ifstat_inc(ifp, ifs6_in_routersolicit); 751 if (code != 0) 752 goto badcode; 753 if (icmp6len < sizeof(struct nd_router_solicit)) 754 goto badlen; 755 if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) == NULL) { 756 /* give up local */ 757 758 /* Send incoming SeND packet to user space. */ 759 if (send_sendso_input_hook != NULL) { 760 IP6_EXTHDR_CHECK(m, off, 761 icmp6len, IPPROTO_DONE); 762 error = send_sendso_input_hook(m, ifp, 763 SND_IN, ip6len); 764 /* -1 == no app on SEND socket */ 765 if (error == 0) 766 return (IPPROTO_DONE); 767 nd6_rs_input(m, off, icmp6len); 768 } else 769 nd6_rs_input(m, off, icmp6len); 770 m = NULL; 771 goto freeit; 772 } 773 if (send_sendso_input_hook != NULL) { 774 IP6_EXTHDR_CHECK(n, off, 775 icmp6len, IPPROTO_DONE); 776 error = send_sendso_input_hook(n, ifp, 777 SND_IN, ip6len); 778 if (error == 0) 779 goto freeit; 780 /* -1 == no app on SEND socket */ 781 nd6_rs_input(n, off, icmp6len); 782 } else 783 nd6_rs_input(n, off, icmp6len); 784 /* m stays. */ 785 break; 786 787 case ND_ROUTER_ADVERT: 788 icmp6_ifstat_inc(ifp, ifs6_in_routeradvert); 789 if (code != 0) 790 goto badcode; 791 if (icmp6len < sizeof(struct nd_router_advert)) 792 goto badlen; 793 if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) == NULL) { 794 795 /* Send incoming SeND-protected/ND packet to user space. */ 796 if (send_sendso_input_hook != NULL) { 797 error = send_sendso_input_hook(m, ifp, 798 SND_IN, ip6len); 799 if (error == 0) 800 return (IPPROTO_DONE); 801 nd6_ra_input(m, off, icmp6len); 802 } else 803 nd6_ra_input(m, off, icmp6len); 804 m = NULL; 805 goto freeit; 806 } 807 if (send_sendso_input_hook != NULL) { 808 error = send_sendso_input_hook(n, ifp, 809 SND_IN, ip6len); 810 if (error == 0) 811 goto freeit; 812 nd6_ra_input(n, off, icmp6len); 813 } else 814 nd6_ra_input(n, off, icmp6len); 815 /* m stays. */ 816 break; 817 818 case ND_NEIGHBOR_SOLICIT: 819 icmp6_ifstat_inc(ifp, ifs6_in_neighborsolicit); 820 if (code != 0) 821 goto badcode; 822 if (icmp6len < sizeof(struct nd_neighbor_solicit)) 823 goto badlen; 824 if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) == NULL) { 825 if (send_sendso_input_hook != NULL) { 826 error = send_sendso_input_hook(m, ifp, 827 SND_IN, ip6len); 828 if (error == 0) 829 return (IPPROTO_DONE); 830 nd6_ns_input(m, off, icmp6len); 831 } else 832 nd6_ns_input(m, off, icmp6len); 833 m = NULL; 834 goto freeit; 835 } 836 if (send_sendso_input_hook != NULL) { 837 error = send_sendso_input_hook(n, ifp, 838 SND_IN, ip6len); 839 if (error == 0) 840 goto freeit; 841 nd6_ns_input(n, off, icmp6len); 842 } else 843 nd6_ns_input(n, off, icmp6len); 844 /* m stays. */ 845 break; 846 847 case ND_NEIGHBOR_ADVERT: 848 icmp6_ifstat_inc(ifp, ifs6_in_neighboradvert); 849 if (code != 0) 850 goto badcode; 851 if (icmp6len < sizeof(struct nd_neighbor_advert)) 852 goto badlen; 853 if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) == NULL) { 854 855 /* Send incoming SeND-protected/ND packet to user space. */ 856 if (send_sendso_input_hook != NULL) { 857 error = send_sendso_input_hook(m, ifp, 858 SND_IN, ip6len); 859 if (error == 0) 860 return (IPPROTO_DONE); 861 nd6_na_input(m, off, icmp6len); 862 } else 863 nd6_na_input(m, off, icmp6len); 864 m = NULL; 865 goto freeit; 866 } 867 if (send_sendso_input_hook != NULL) { 868 error = send_sendso_input_hook(n, ifp, 869 SND_IN, ip6len); 870 if (error == 0) 871 goto freeit; 872 nd6_na_input(n, off, icmp6len); 873 } else 874 nd6_na_input(n, off, icmp6len); 875 /* m stays. */ 876 break; 877 878 case ND_REDIRECT: 879 icmp6_ifstat_inc(ifp, ifs6_in_redirect); 880 if (code != 0) 881 goto badcode; 882 if (icmp6len < sizeof(struct nd_redirect)) 883 goto badlen; 884 if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) == NULL) { 885 if (send_sendso_input_hook != NULL) { 886 error = send_sendso_input_hook(m, ifp, 887 SND_IN, ip6len); 888 if (error == 0) 889 return (IPPROTO_DONE); 890 icmp6_redirect_input(m, off); 891 } else 892 icmp6_redirect_input(m, off); 893 m = NULL; 894 goto freeit; 895 } 896 if (send_sendso_input_hook != NULL) { 897 error = send_sendso_input_hook(n, ifp, 898 SND_IN, ip6len); 899 if (error == 0) 900 goto freeit; 901 icmp6_redirect_input(n, off); 902 } else 903 icmp6_redirect_input(n, off); 904 /* m stays. */ 905 break; 906 907 case ICMP6_ROUTER_RENUMBERING: 908 if (code != ICMP6_ROUTER_RENUMBERING_COMMAND && 909 code != ICMP6_ROUTER_RENUMBERING_RESULT) 910 goto badcode; 911 if (icmp6len < sizeof(struct icmp6_router_renum)) 912 goto badlen; 913 break; 914 915 default: 916 nd6log((LOG_DEBUG, 917 "icmp6_input: unknown type %d(src=%s, dst=%s, ifid=%d)\n", 918 icmp6->icmp6_type, ip6_sprintf(ip6bufs, &ip6->ip6_src), 919 ip6_sprintf(ip6bufd, &ip6->ip6_dst), 920 ifp ? ifp->if_index : 0)); 921 if (icmp6->icmp6_type < ICMP6_ECHO_REQUEST) { 922 /* ICMPv6 error: MUST deliver it by spec... */ 923 code = PRC_NCMDS; 924 /* deliver */ 925 } else { 926 /* ICMPv6 informational: MUST not deliver */ 927 break; 928 } 929 deliver: 930 if (icmp6_notify_error(&m, off, icmp6len, code) != 0) { 931 /* In this case, m should've been freed. */ 932 return (IPPROTO_DONE); 933 } 934 break; 935 936 badcode: 937 ICMP6STAT_INC(icp6s_badcode); 938 break; 939 940 badlen: 941 ICMP6STAT_INC(icp6s_badlen); 942 break; 943 } 944 945 /* deliver the packet to appropriate sockets */ 946 icmp6_rip6_input(&m, *offp); 947 948 return IPPROTO_DONE; 949 950 freeit: 951 m_freem(m); 952 return IPPROTO_DONE; 953} 954 955static int 956icmp6_notify_error(struct mbuf **mp, int off, int icmp6len, int code) 957{ 958 struct mbuf *m = *mp; 959 struct icmp6_hdr *icmp6; 960 struct ip6_hdr *eip6; 961 u_int32_t notifymtu; 962 struct sockaddr_in6 icmp6src, icmp6dst; 963 964 if (icmp6len < sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr)) { 965 ICMP6STAT_INC(icp6s_tooshort); 966 goto freeit; 967 } 968#ifndef PULLDOWN_TEST 969 IP6_EXTHDR_CHECK(m, off, 970 sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr), -1); 971 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 972#else 973 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, 974 sizeof(*icmp6) + sizeof(struct ip6_hdr)); 975 if (icmp6 == NULL) { 976 ICMP6STAT_INC(icp6s_tooshort); 977 return (-1); 978 } 979#endif 980 eip6 = (struct ip6_hdr *)(icmp6 + 1); 981 982 /* Detect the upper level protocol */ 983 { 984 void (*ctlfunc)(int, struct sockaddr *, void *); 985 u_int8_t nxt = eip6->ip6_nxt; 986 int eoff = off + sizeof(struct icmp6_hdr) + 987 sizeof(struct ip6_hdr); 988 struct ip6ctlparam ip6cp; 989 struct in6_addr *finaldst = NULL; 990 int icmp6type = icmp6->icmp6_type; 991 struct ip6_frag *fh; 992 struct ip6_rthdr *rth; 993 struct ip6_rthdr0 *rth0; 994 int rthlen; 995 996 while (1) { /* XXX: should avoid infinite loop explicitly? */ 997 struct ip6_ext *eh; 998 999 switch (nxt) { 1000 case IPPROTO_HOPOPTS: 1001 case IPPROTO_DSTOPTS: 1002 case IPPROTO_AH: 1003#ifndef PULLDOWN_TEST 1004 IP6_EXTHDR_CHECK(m, 0, 1005 eoff + sizeof(struct ip6_ext), -1); 1006 eh = (struct ip6_ext *)(mtod(m, caddr_t) + eoff); 1007#else 1008 IP6_EXTHDR_GET(eh, struct ip6_ext *, m, 1009 eoff, sizeof(*eh)); 1010 if (eh == NULL) { 1011 ICMP6STAT_INC(icp6s_tooshort); 1012 return (-1); 1013 } 1014#endif 1015 1016 if (nxt == IPPROTO_AH) 1017 eoff += (eh->ip6e_len + 2) << 2; 1018 else 1019 eoff += (eh->ip6e_len + 1) << 3; 1020 nxt = eh->ip6e_nxt; 1021 break; 1022 case IPPROTO_ROUTING: 1023 /* 1024 * When the erroneous packet contains a 1025 * routing header, we should examine the 1026 * header to determine the final destination. 1027 * Otherwise, we can't properly update 1028 * information that depends on the final 1029 * destination (e.g. path MTU). 1030 */ 1031#ifndef PULLDOWN_TEST 1032 IP6_EXTHDR_CHECK(m, 0, eoff + sizeof(*rth), -1); 1033 rth = (struct ip6_rthdr *) 1034 (mtod(m, caddr_t) + eoff); 1035#else 1036 IP6_EXTHDR_GET(rth, struct ip6_rthdr *, m, 1037 eoff, sizeof(*rth)); 1038 if (rth == NULL) { 1039 ICMP6STAT_INC(icp6s_tooshort); 1040 return (-1); 1041 } 1042#endif 1043 rthlen = (rth->ip6r_len + 1) << 3; 1044 /* 1045 * XXX: currently there is no 1046 * officially defined type other 1047 * than type-0. 1048 * Note that if the segment left field 1049 * is 0, all intermediate hops must 1050 * have been passed. 1051 */ 1052 if (rth->ip6r_segleft && 1053 rth->ip6r_type == IPV6_RTHDR_TYPE_0) { 1054 int hops; 1055 1056#ifndef PULLDOWN_TEST 1057 IP6_EXTHDR_CHECK(m, 0, eoff + rthlen, -1); 1058 rth0 = (struct ip6_rthdr0 *) 1059 (mtod(m, caddr_t) + eoff); 1060#else 1061 IP6_EXTHDR_GET(rth0, 1062 struct ip6_rthdr0 *, m, 1063 eoff, rthlen); 1064 if (rth0 == NULL) { 1065 ICMP6STAT_INC(icp6s_tooshort); 1066 return (-1); 1067 } 1068#endif 1069 /* just ignore a bogus header */ 1070 if ((rth0->ip6r0_len % 2) == 0 && 1071 (hops = rth0->ip6r0_len/2)) 1072 finaldst = (struct in6_addr *)(rth0 + 1) + (hops - 1); 1073 } 1074 eoff += rthlen; 1075 nxt = rth->ip6r_nxt; 1076 break; 1077 case IPPROTO_FRAGMENT: 1078#ifndef PULLDOWN_TEST 1079 IP6_EXTHDR_CHECK(m, 0, eoff + 1080 sizeof(struct ip6_frag), -1); 1081 fh = (struct ip6_frag *)(mtod(m, caddr_t) + 1082 eoff); 1083#else 1084 IP6_EXTHDR_GET(fh, struct ip6_frag *, m, 1085 eoff, sizeof(*fh)); 1086 if (fh == NULL) { 1087 ICMP6STAT_INC(icp6s_tooshort); 1088 return (-1); 1089 } 1090#endif 1091 /* 1092 * Data after a fragment header is meaningless 1093 * unless it is the first fragment, but 1094 * we'll go to the notify label for path MTU 1095 * discovery. 1096 */ 1097 if (fh->ip6f_offlg & IP6F_OFF_MASK) 1098 goto notify; 1099 1100 eoff += sizeof(struct ip6_frag); 1101 nxt = fh->ip6f_nxt; 1102 break; 1103 default: 1104 /* 1105 * This case includes ESP and the No Next 1106 * Header. In such cases going to the notify 1107 * label does not have any meaning 1108 * (i.e. ctlfunc will be NULL), but we go 1109 * anyway since we might have to update 1110 * path MTU information. 1111 */ 1112 goto notify; 1113 } 1114 } 1115 notify: 1116#ifndef PULLDOWN_TEST 1117 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 1118#else 1119 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, 1120 sizeof(*icmp6) + sizeof(struct ip6_hdr)); 1121 if (icmp6 == NULL) { 1122 ICMP6STAT_INC(icp6s_tooshort); 1123 return (-1); 1124 } 1125#endif 1126 1127 /* 1128 * retrieve parameters from the inner IPv6 header, and convert 1129 * them into sockaddr structures. 1130 * XXX: there is no guarantee that the source or destination 1131 * addresses of the inner packet are in the same scope as 1132 * the addresses of the icmp packet. But there is no other 1133 * way to determine the zone. 1134 */ 1135 eip6 = (struct ip6_hdr *)(icmp6 + 1); 1136 1137 bzero(&icmp6dst, sizeof(icmp6dst)); 1138 icmp6dst.sin6_len = sizeof(struct sockaddr_in6); 1139 icmp6dst.sin6_family = AF_INET6; 1140 if (finaldst == NULL) 1141 icmp6dst.sin6_addr = eip6->ip6_dst; 1142 else 1143 icmp6dst.sin6_addr = *finaldst; 1144 if (in6_setscope(&icmp6dst.sin6_addr, m->m_pkthdr.rcvif, NULL)) 1145 goto freeit; 1146 bzero(&icmp6src, sizeof(icmp6src)); 1147 icmp6src.sin6_len = sizeof(struct sockaddr_in6); 1148 icmp6src.sin6_family = AF_INET6; 1149 icmp6src.sin6_addr = eip6->ip6_src; 1150 if (in6_setscope(&icmp6src.sin6_addr, m->m_pkthdr.rcvif, NULL)) 1151 goto freeit; 1152 icmp6src.sin6_flowinfo = 1153 (eip6->ip6_flow & IPV6_FLOWLABEL_MASK); 1154 1155 if (finaldst == NULL) 1156 finaldst = &eip6->ip6_dst; 1157 ip6cp.ip6c_m = m; 1158 ip6cp.ip6c_icmp6 = icmp6; 1159 ip6cp.ip6c_ip6 = (struct ip6_hdr *)(icmp6 + 1); 1160 ip6cp.ip6c_off = eoff; 1161 ip6cp.ip6c_finaldst = finaldst; 1162 ip6cp.ip6c_src = &icmp6src; 1163 ip6cp.ip6c_nxt = nxt; 1164 1165 if (icmp6type == ICMP6_PACKET_TOO_BIG) { 1166 notifymtu = ntohl(icmp6->icmp6_mtu); 1167 ip6cp.ip6c_cmdarg = (void *)¬ifymtu; 1168 icmp6_mtudisc_update(&ip6cp, 1); /*XXX*/ 1169 } 1170 1171 ctlfunc = (void (*)(int, struct sockaddr *, void *)) 1172 (inet6sw[ip6_protox[nxt]].pr_ctlinput); 1173 if (ctlfunc) { 1174 (void) (*ctlfunc)(code, (struct sockaddr *)&icmp6dst, 1175 &ip6cp); 1176 } 1177 } 1178 *mp = m; 1179 return (0); 1180 1181 freeit: 1182 m_freem(m); 1183 return (-1); 1184} 1185 1186void 1187icmp6_mtudisc_update(struct ip6ctlparam *ip6cp, int validated) 1188{ 1189 struct in6_addr *dst = ip6cp->ip6c_finaldst; 1190 struct icmp6_hdr *icmp6 = ip6cp->ip6c_icmp6; 1191 struct mbuf *m = ip6cp->ip6c_m; /* will be necessary for scope issue */ 1192 u_int mtu = ntohl(icmp6->icmp6_mtu); 1193 struct in_conninfo inc; 1194 1195#if 0 1196 /* 1197 * RFC2460 section 5, last paragraph. 1198 * even though minimum link MTU for IPv6 is IPV6_MMTU, 1199 * we may see ICMPv6 too big with mtu < IPV6_MMTU 1200 * due to packet translator in the middle. 1201 * see ip6_output() and ip6_getpmtu() "alwaysfrag" case for 1202 * special handling. 1203 */ 1204 if (mtu < IPV6_MMTU) 1205 return; 1206#endif 1207 1208 /* 1209 * we reject ICMPv6 too big with abnormally small value. 1210 * XXX what is the good definition of "abnormally small"? 1211 */ 1212 if (mtu < sizeof(struct ip6_hdr) + sizeof(struct ip6_frag) + 8) 1213 return; 1214 1215 if (!validated) 1216 return; 1217 1218 /* 1219 * In case the suggested mtu is less than IPV6_MMTU, we 1220 * only need to remember that it was for above mentioned 1221 * "alwaysfrag" case. 1222 * Try to be as close to the spec as possible. 1223 */ 1224 if (mtu < IPV6_MMTU) 1225 mtu = IPV6_MMTU - 8; 1226 1227 bzero(&inc, sizeof(inc)); 1228 inc.inc_fibnum = M_GETFIB(m); 1229 inc.inc_flags |= INC_ISIPV6; 1230 inc.inc6_faddr = *dst; 1231 if (in6_setscope(&inc.inc6_faddr, m->m_pkthdr.rcvif, NULL)) 1232 return; 1233 1234 if (mtu < tcp_maxmtu6(&inc, NULL)) { 1235 tcp_hc_updatemtu(&inc, mtu); 1236 ICMP6STAT_INC(icp6s_pmtuchg); 1237 } 1238} 1239 1240/* 1241 * Process a Node Information Query packet, based on 1242 * draft-ietf-ipngwg-icmp-name-lookups-07. 1243 * 1244 * Spec incompatibilities: 1245 * - IPv6 Subject address handling 1246 * - IPv4 Subject address handling support missing 1247 * - Proxy reply (answer even if it's not for me) 1248 * - joins NI group address at in6_ifattach() time only, does not cope 1249 * with hostname changes by sethostname(3) 1250 */ 1251static struct mbuf * 1252ni6_input(struct mbuf *m, int off) 1253{ 1254 struct icmp6_nodeinfo *ni6, *nni6; 1255 struct mbuf *n = NULL; 1256 struct prison *pr; 1257 u_int16_t qtype; 1258 int subjlen; 1259 int replylen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo); 1260 struct ni_reply_fqdn *fqdn; 1261 int addrs; /* for NI_QTYPE_NODEADDR */ 1262 struct ifnet *ifp = NULL; /* for NI_QTYPE_NODEADDR */ 1263 struct in6_addr in6_subj; /* subject address */ 1264 struct ip6_hdr *ip6; 1265 int oldfqdn = 0; /* if 1, return pascal string (03 draft) */ 1266 char *subj = NULL; 1267 struct in6_ifaddr *ia6 = NULL; 1268 1269 ip6 = mtod(m, struct ip6_hdr *); 1270#ifndef PULLDOWN_TEST 1271 ni6 = (struct icmp6_nodeinfo *)(mtod(m, caddr_t) + off); 1272#else 1273 IP6_EXTHDR_GET(ni6, struct icmp6_nodeinfo *, m, off, sizeof(*ni6)); 1274 if (ni6 == NULL) { 1275 /* m is already reclaimed */ 1276 return (NULL); 1277 } 1278#endif 1279 1280 /* 1281 * Validate IPv6 source address. 1282 * The default configuration MUST be to refuse answering queries from 1283 * global-scope addresses according to RFC4602. 1284 * Notes: 1285 * - it's not very clear what "refuse" means; this implementation 1286 * simply drops it. 1287 * - it's not very easy to identify global-scope (unicast) addresses 1288 * since there are many prefixes for them. It should be safer 1289 * and in practice sufficient to check "all" but loopback and 1290 * link-local (note that site-local unicast was deprecated and 1291 * ULA is defined as global scope-wise) 1292 */ 1293 if ((V_icmp6_nodeinfo & ICMP6_NODEINFO_GLOBALOK) == 0 && 1294 !IN6_IS_ADDR_LOOPBACK(&ip6->ip6_src) && 1295 !IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_src)) 1296 goto bad; 1297 1298 /* 1299 * Validate IPv6 destination address. 1300 * 1301 * The Responder must discard the Query without further processing 1302 * unless it is one of the Responder's unicast or anycast addresses, or 1303 * a link-local scope multicast address which the Responder has joined. 1304 * [RFC4602, Section 5.] 1305 */ 1306 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 1307 if (!IN6_IS_ADDR_MC_LINKLOCAL(&ip6->ip6_dst)) 1308 goto bad; 1309 /* else it's a link-local multicast, fine */ 1310 } else { /* unicast or anycast */ 1311 if ((ia6 = ip6_getdstifaddr(m)) == NULL) 1312 goto bad; /* XXX impossible */ 1313 1314 if ((ia6->ia6_flags & IN6_IFF_TEMPORARY) && 1315 !(V_icmp6_nodeinfo & ICMP6_NODEINFO_TMPADDROK)) { 1316 ifa_free(&ia6->ia_ifa); 1317 nd6log((LOG_DEBUG, "ni6_input: ignore node info to " 1318 "a temporary address in %s:%d", 1319 __FILE__, __LINE__)); 1320 goto bad; 1321 } 1322 ifa_free(&ia6->ia_ifa); 1323 } 1324 1325 /* validate query Subject field. */ 1326 qtype = ntohs(ni6->ni_qtype); 1327 subjlen = m->m_pkthdr.len - off - sizeof(struct icmp6_nodeinfo); 1328 switch (qtype) { 1329 case NI_QTYPE_NOOP: 1330 case NI_QTYPE_SUPTYPES: 1331 /* 07 draft */ 1332 if (ni6->ni_code == ICMP6_NI_SUBJ_FQDN && subjlen == 0) 1333 break; 1334 /* FALLTHROUGH */ 1335 case NI_QTYPE_FQDN: 1336 case NI_QTYPE_NODEADDR: 1337 case NI_QTYPE_IPV4ADDR: 1338 switch (ni6->ni_code) { 1339 case ICMP6_NI_SUBJ_IPV6: 1340#if ICMP6_NI_SUBJ_IPV6 != 0 1341 case 0: 1342#endif 1343 /* 1344 * backward compatibility - try to accept 03 draft 1345 * format, where no Subject is present. 1346 */ 1347 if (qtype == NI_QTYPE_FQDN && ni6->ni_code == 0 && 1348 subjlen == 0) { 1349 oldfqdn++; 1350 break; 1351 } 1352#if ICMP6_NI_SUBJ_IPV6 != 0 1353 if (ni6->ni_code != ICMP6_NI_SUBJ_IPV6) 1354 goto bad; 1355#endif 1356 1357 if (subjlen != sizeof(struct in6_addr)) 1358 goto bad; 1359 1360 /* 1361 * Validate Subject address. 1362 * 1363 * Not sure what exactly "address belongs to the node" 1364 * means in the spec, is it just unicast, or what? 1365 * 1366 * At this moment we consider Subject address as 1367 * "belong to the node" if the Subject address equals 1368 * to the IPv6 destination address; validation for 1369 * IPv6 destination address should have done enough 1370 * check for us. 1371 * 1372 * We do not do proxy at this moment. 1373 */ 1374 /* m_pulldown instead of copy? */ 1375 m_copydata(m, off + sizeof(struct icmp6_nodeinfo), 1376 subjlen, (caddr_t)&in6_subj); 1377 if (in6_setscope(&in6_subj, m->m_pkthdr.rcvif, NULL)) 1378 goto bad; 1379 1380 subj = (char *)&in6_subj; 1381 if (IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, &in6_subj)) 1382 break; 1383 1384 /* 1385 * XXX if we are to allow other cases, we should really 1386 * be careful about scope here. 1387 * basically, we should disallow queries toward IPv6 1388 * destination X with subject Y, 1389 * if scope(X) > scope(Y). 1390 * if we allow scope(X) > scope(Y), it will result in 1391 * information leakage across scope boundary. 1392 */ 1393 goto bad; 1394 1395 case ICMP6_NI_SUBJ_FQDN: 1396 /* 1397 * Validate Subject name with gethostname(3). 1398 * 1399 * The behavior may need some debate, since: 1400 * - we are not sure if the node has FQDN as 1401 * hostname (returned by gethostname(3)). 1402 * - the code does wildcard match for truncated names. 1403 * however, we are not sure if we want to perform 1404 * wildcard match, if gethostname(3) side has 1405 * truncated hostname. 1406 */ 1407 pr = curthread->td_ucred->cr_prison; 1408 mtx_lock(&pr->pr_mtx); 1409 n = ni6_nametodns(pr->pr_hostname, 1410 strlen(pr->pr_hostname), 0); 1411 mtx_unlock(&pr->pr_mtx); 1412 if (!n || n->m_next || n->m_len == 0) 1413 goto bad; 1414 IP6_EXTHDR_GET(subj, char *, m, 1415 off + sizeof(struct icmp6_nodeinfo), subjlen); 1416 if (subj == NULL) 1417 goto bad; 1418 if (!ni6_dnsmatch(subj, subjlen, mtod(n, const char *), 1419 n->m_len)) { 1420 goto bad; 1421 } 1422 m_freem(n); 1423 n = NULL; 1424 break; 1425 1426 case ICMP6_NI_SUBJ_IPV4: /* XXX: to be implemented? */ 1427 default: 1428 goto bad; 1429 } 1430 break; 1431 } 1432 1433 /* refuse based on configuration. XXX ICMP6_NI_REFUSED? */ 1434 switch (qtype) { 1435 case NI_QTYPE_FQDN: 1436 if ((V_icmp6_nodeinfo & ICMP6_NODEINFO_FQDNOK) == 0) 1437 goto bad; 1438 break; 1439 case NI_QTYPE_NODEADDR: 1440 case NI_QTYPE_IPV4ADDR: 1441 if ((V_icmp6_nodeinfo & ICMP6_NODEINFO_NODEADDROK) == 0) 1442 goto bad; 1443 break; 1444 } 1445 1446 /* guess reply length */ 1447 switch (qtype) { 1448 case NI_QTYPE_NOOP: 1449 break; /* no reply data */ 1450 case NI_QTYPE_SUPTYPES: 1451 replylen += sizeof(u_int32_t); 1452 break; 1453 case NI_QTYPE_FQDN: 1454 /* XXX will append an mbuf */ 1455 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1456 break; 1457 case NI_QTYPE_NODEADDR: 1458 addrs = ni6_addrs(ni6, m, &ifp, (struct in6_addr *)subj); 1459 if ((replylen += addrs * (sizeof(struct in6_addr) + 1460 sizeof(u_int32_t))) > MCLBYTES) 1461 replylen = MCLBYTES; /* XXX: will truncate pkt later */ 1462 break; 1463 case NI_QTYPE_IPV4ADDR: 1464 /* unsupported - should respond with unknown Qtype? */ 1465 break; 1466 default: 1467 /* 1468 * XXX: We must return a reply with the ICMP6 code 1469 * `unknown Qtype' in this case. However we regard the case 1470 * as an FQDN query for backward compatibility. 1471 * Older versions set a random value to this field, 1472 * so it rarely varies in the defined qtypes. 1473 * But the mechanism is not reliable... 1474 * maybe we should obsolete older versions. 1475 */ 1476 qtype = NI_QTYPE_FQDN; 1477 /* XXX will append an mbuf */ 1478 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1479 oldfqdn++; 1480 break; 1481 } 1482 1483 /* Allocate an mbuf to reply. */ 1484 if (replylen > MCLBYTES) { 1485 /* 1486 * XXX: should we try to allocate more? But MCLBYTES 1487 * is probably much larger than IPV6_MMTU... 1488 */ 1489 goto bad; 1490 } 1491 if (replylen > MHLEN) 1492 n = m_getcl(M_NOWAIT, m->m_type, M_PKTHDR); 1493 else 1494 n = m_gethdr(M_NOWAIT, m->m_type); 1495 if (n == NULL) { 1496 m_freem(m); 1497 return (NULL); 1498 } 1499 m_move_pkthdr(n, m); /* just for recvif and FIB */ 1500 n->m_pkthdr.len = n->m_len = replylen; 1501 1502 /* copy mbuf header and IPv6 + Node Information base headers */ 1503 bcopy(mtod(m, caddr_t), mtod(n, caddr_t), sizeof(struct ip6_hdr)); 1504 nni6 = (struct icmp6_nodeinfo *)(mtod(n, struct ip6_hdr *) + 1); 1505 bcopy((caddr_t)ni6, (caddr_t)nni6, sizeof(struct icmp6_nodeinfo)); 1506 1507 /* qtype dependent procedure */ 1508 switch (qtype) { 1509 case NI_QTYPE_NOOP: 1510 nni6->ni_code = ICMP6_NI_SUCCESS; 1511 nni6->ni_flags = 0; 1512 break; 1513 case NI_QTYPE_SUPTYPES: 1514 { 1515 u_int32_t v; 1516 nni6->ni_code = ICMP6_NI_SUCCESS; 1517 nni6->ni_flags = htons(0x0000); /* raw bitmap */ 1518 /* supports NOOP, SUPTYPES, FQDN, and NODEADDR */ 1519 v = (u_int32_t)htonl(0x0000000f); 1520 bcopy(&v, nni6 + 1, sizeof(u_int32_t)); 1521 break; 1522 } 1523 case NI_QTYPE_FQDN: 1524 nni6->ni_code = ICMP6_NI_SUCCESS; 1525 fqdn = (struct ni_reply_fqdn *)(mtod(n, caddr_t) + 1526 sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo)); 1527 nni6->ni_flags = 0; /* XXX: meaningless TTL */ 1528 fqdn->ni_fqdn_ttl = 0; /* ditto. */ 1529 /* 1530 * XXX do we really have FQDN in hostname? 1531 */ 1532 pr = curthread->td_ucred->cr_prison; 1533 mtx_lock(&pr->pr_mtx); 1534 n->m_next = ni6_nametodns(pr->pr_hostname, 1535 strlen(pr->pr_hostname), oldfqdn); 1536 mtx_unlock(&pr->pr_mtx); 1537 if (n->m_next == NULL) 1538 goto bad; 1539 /* XXX we assume that n->m_next is not a chain */ 1540 if (n->m_next->m_next != NULL) 1541 goto bad; 1542 n->m_pkthdr.len += n->m_next->m_len; 1543 break; 1544 case NI_QTYPE_NODEADDR: 1545 { 1546 int lenlim, copied; 1547 1548 nni6->ni_code = ICMP6_NI_SUCCESS; 1549 n->m_pkthdr.len = n->m_len = 1550 sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo); 1551 lenlim = M_TRAILINGSPACE(n); 1552 copied = ni6_store_addrs(ni6, nni6, ifp, lenlim); 1553 /* XXX: reset mbuf length */ 1554 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) + 1555 sizeof(struct icmp6_nodeinfo) + copied; 1556 break; 1557 } 1558 default: 1559 break; /* XXX impossible! */ 1560 } 1561 1562 nni6->ni_type = ICMP6_NI_REPLY; 1563 m_freem(m); 1564 return (n); 1565 1566 bad: 1567 m_freem(m); 1568 if (n) 1569 m_freem(n); 1570 return (NULL); 1571} 1572 1573/* 1574 * make a mbuf with DNS-encoded string. no compression support. 1575 * 1576 * XXX names with less than 2 dots (like "foo" or "foo.section") will be 1577 * treated as truncated name (two \0 at the end). this is a wild guess. 1578 * 1579 * old - return pascal string if non-zero 1580 */ 1581static struct mbuf * 1582ni6_nametodns(const char *name, int namelen, int old) 1583{ 1584 struct mbuf *m; 1585 char *cp, *ep; 1586 const char *p, *q; 1587 int i, len, nterm; 1588 1589 if (old) 1590 len = namelen + 1; 1591 else 1592 len = MCLBYTES; 1593 1594 /* Because MAXHOSTNAMELEN is usually 256, we use cluster mbuf. */ 1595 if (len > MLEN) 1596 m = m_getcl(M_NOWAIT, MT_DATA, 0); 1597 else 1598 m = m_get(M_NOWAIT, MT_DATA); 1599 if (m == NULL) 1600 goto fail; 1601 1602 if (old) { 1603 m->m_len = len; 1604 *mtod(m, char *) = namelen; 1605 bcopy(name, mtod(m, char *) + 1, namelen); 1606 return m; 1607 } else { 1608 m->m_len = 0; 1609 cp = mtod(m, char *); 1610 ep = mtod(m, char *) + M_TRAILINGSPACE(m); 1611 1612 /* if not certain about my name, return empty buffer */ 1613 if (namelen == 0) 1614 return m; 1615 1616 /* 1617 * guess if it looks like shortened hostname, or FQDN. 1618 * shortened hostname needs two trailing "\0". 1619 */ 1620 i = 0; 1621 for (p = name; p < name + namelen; p++) { 1622 if (*p && *p == '.') 1623 i++; 1624 } 1625 if (i < 2) 1626 nterm = 2; 1627 else 1628 nterm = 1; 1629 1630 p = name; 1631 while (cp < ep && p < name + namelen) { 1632 i = 0; 1633 for (q = p; q < name + namelen && *q && *q != '.'; q++) 1634 i++; 1635 /* result does not fit into mbuf */ 1636 if (cp + i + 1 >= ep) 1637 goto fail; 1638 /* 1639 * DNS label length restriction, RFC1035 page 8. 1640 * "i == 0" case is included here to avoid returning 1641 * 0-length label on "foo..bar". 1642 */ 1643 if (i <= 0 || i >= 64) 1644 goto fail; 1645 *cp++ = i; 1646 bcopy(p, cp, i); 1647 cp += i; 1648 p = q; 1649 if (p < name + namelen && *p == '.') 1650 p++; 1651 } 1652 /* termination */ 1653 if (cp + nterm >= ep) 1654 goto fail; 1655 while (nterm-- > 0) 1656 *cp++ = '\0'; 1657 m->m_len = cp - mtod(m, char *); 1658 return m; 1659 } 1660 1661 panic("should not reach here"); 1662 /* NOTREACHED */ 1663 1664 fail: 1665 if (m) 1666 m_freem(m); 1667 return NULL; 1668} 1669 1670/* 1671 * check if two DNS-encoded string matches. takes care of truncated 1672 * form (with \0\0 at the end). no compression support. 1673 * XXX upper/lowercase match (see RFC2065) 1674 */ 1675static int 1676ni6_dnsmatch(const char *a, int alen, const char *b, int blen) 1677{ 1678 const char *a0, *b0; 1679 int l; 1680 1681 /* simplest case - need validation? */ 1682 if (alen == blen && bcmp(a, b, alen) == 0) 1683 return 1; 1684 1685 a0 = a; 1686 b0 = b; 1687 1688 /* termination is mandatory */ 1689 if (alen < 2 || blen < 2) 1690 return 0; 1691 if (a0[alen - 1] != '\0' || b0[blen - 1] != '\0') 1692 return 0; 1693 alen--; 1694 blen--; 1695 1696 while (a - a0 < alen && b - b0 < blen) { 1697 if (a - a0 + 1 > alen || b - b0 + 1 > blen) 1698 return 0; 1699 1700 if ((signed char)a[0] < 0 || (signed char)b[0] < 0) 1701 return 0; 1702 /* we don't support compression yet */ 1703 if (a[0] >= 64 || b[0] >= 64) 1704 return 0; 1705 1706 /* truncated case */ 1707 if (a[0] == 0 && a - a0 == alen - 1) 1708 return 1; 1709 if (b[0] == 0 && b - b0 == blen - 1) 1710 return 1; 1711 if (a[0] == 0 || b[0] == 0) 1712 return 0; 1713 1714 if (a[0] != b[0]) 1715 return 0; 1716 l = a[0]; 1717 if (a - a0 + 1 + l > alen || b - b0 + 1 + l > blen) 1718 return 0; 1719 if (bcmp(a + 1, b + 1, l) != 0) 1720 return 0; 1721 1722 a += 1 + l; 1723 b += 1 + l; 1724 } 1725 1726 if (a - a0 == alen && b - b0 == blen) 1727 return 1; 1728 else 1729 return 0; 1730} 1731 1732/* 1733 * calculate the number of addresses to be returned in the node info reply. 1734 */ 1735static int 1736ni6_addrs(struct icmp6_nodeinfo *ni6, struct mbuf *m, struct ifnet **ifpp, 1737 struct in6_addr *subj) 1738{ 1739 struct ifnet *ifp; 1740 struct in6_ifaddr *ifa6; 1741 struct ifaddr *ifa; 1742 int addrs = 0, addrsofif, iffound = 0; 1743 int niflags = ni6->ni_flags; 1744 1745 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0) { 1746 switch (ni6->ni_code) { 1747 case ICMP6_NI_SUBJ_IPV6: 1748 if (subj == NULL) /* must be impossible... */ 1749 return (0); 1750 break; 1751 default: 1752 /* 1753 * XXX: we only support IPv6 subject address for 1754 * this Qtype. 1755 */ 1756 return (0); 1757 } 1758 } 1759 1760 IFNET_RLOCK_NOSLEEP(); 1761 TAILQ_FOREACH(ifp, &V_ifnet, if_list) { 1762 addrsofif = 0; 1763 IF_ADDR_RLOCK(ifp); 1764 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 1765 if (ifa->ifa_addr->sa_family != AF_INET6) 1766 continue; 1767 ifa6 = (struct in6_ifaddr *)ifa; 1768 1769 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0 && 1770 IN6_ARE_ADDR_EQUAL(subj, &ifa6->ia_addr.sin6_addr)) 1771 iffound = 1; 1772 1773 /* 1774 * IPv4-mapped addresses can only be returned by a 1775 * Node Information proxy, since they represent 1776 * addresses of IPv4-only nodes, which perforce do 1777 * not implement this protocol. 1778 * [icmp-name-lookups-07, Section 5.4] 1779 * So we don't support NI_NODEADDR_FLAG_COMPAT in 1780 * this function at this moment. 1781 */ 1782 1783 /* What do we have to do about ::1? */ 1784 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1785 case IPV6_ADDR_SCOPE_LINKLOCAL: 1786 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0) 1787 continue; 1788 break; 1789 case IPV6_ADDR_SCOPE_SITELOCAL: 1790 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0) 1791 continue; 1792 break; 1793 case IPV6_ADDR_SCOPE_GLOBAL: 1794 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0) 1795 continue; 1796 break; 1797 default: 1798 continue; 1799 } 1800 1801 /* 1802 * check if anycast is okay. 1803 * XXX: just experimental. not in the spec. 1804 */ 1805 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 && 1806 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0) 1807 continue; /* we need only unicast addresses */ 1808 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 1809 (V_icmp6_nodeinfo & ICMP6_NODEINFO_TMPADDROK) == 0) { 1810 continue; 1811 } 1812 addrsofif++; /* count the address */ 1813 } 1814 IF_ADDR_RUNLOCK(ifp); 1815 if (iffound) { 1816 *ifpp = ifp; 1817 IFNET_RUNLOCK_NOSLEEP(); 1818 return (addrsofif); 1819 } 1820 1821 addrs += addrsofif; 1822 } 1823 IFNET_RUNLOCK_NOSLEEP(); 1824 1825 return (addrs); 1826} 1827 1828static int 1829ni6_store_addrs(struct icmp6_nodeinfo *ni6, struct icmp6_nodeinfo *nni6, 1830 struct ifnet *ifp0, int resid) 1831{ 1832 struct ifnet *ifp; 1833 struct in6_ifaddr *ifa6; 1834 struct ifaddr *ifa; 1835 struct ifnet *ifp_dep = NULL; 1836 int copied = 0, allow_deprecated = 0; 1837 u_char *cp = (u_char *)(nni6 + 1); 1838 int niflags = ni6->ni_flags; 1839 u_int32_t ltime; 1840 1841 if (ifp0 == NULL && !(niflags & NI_NODEADDR_FLAG_ALL)) 1842 return (0); /* needless to copy */ 1843 1844 IFNET_RLOCK_NOSLEEP(); 1845 ifp = ifp0 ? ifp0 : TAILQ_FIRST(&V_ifnet); 1846 again: 1847 1848 for (; ifp; ifp = TAILQ_NEXT(ifp, if_list)) { 1849 IF_ADDR_RLOCK(ifp); 1850 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 1851 if (ifa->ifa_addr->sa_family != AF_INET6) 1852 continue; 1853 ifa6 = (struct in6_ifaddr *)ifa; 1854 1855 if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) != 0 && 1856 allow_deprecated == 0) { 1857 /* 1858 * prefererred address should be put before 1859 * deprecated addresses. 1860 */ 1861 1862 /* record the interface for later search */ 1863 if (ifp_dep == NULL) 1864 ifp_dep = ifp; 1865 1866 continue; 1867 } else if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) == 0 && 1868 allow_deprecated != 0) 1869 continue; /* we now collect deprecated addrs */ 1870 1871 /* What do we have to do about ::1? */ 1872 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1873 case IPV6_ADDR_SCOPE_LINKLOCAL: 1874 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0) 1875 continue; 1876 break; 1877 case IPV6_ADDR_SCOPE_SITELOCAL: 1878 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0) 1879 continue; 1880 break; 1881 case IPV6_ADDR_SCOPE_GLOBAL: 1882 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0) 1883 continue; 1884 break; 1885 default: 1886 continue; 1887 } 1888 1889 /* 1890 * check if anycast is okay. 1891 * XXX: just experimental. not in the spec. 1892 */ 1893 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 && 1894 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0) 1895 continue; 1896 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 1897 (V_icmp6_nodeinfo & ICMP6_NODEINFO_TMPADDROK) == 0) { 1898 continue; 1899 } 1900 1901 /* now we can copy the address */ 1902 if (resid < sizeof(struct in6_addr) + 1903 sizeof(u_int32_t)) { 1904 IF_ADDR_RUNLOCK(ifp); 1905 /* 1906 * We give up much more copy. 1907 * Set the truncate flag and return. 1908 */ 1909 nni6->ni_flags |= NI_NODEADDR_FLAG_TRUNCATE; 1910 IFNET_RUNLOCK_NOSLEEP(); 1911 return (copied); 1912 } 1913 1914 /* 1915 * Set the TTL of the address. 1916 * The TTL value should be one of the following 1917 * according to the specification: 1918 * 1919 * 1. The remaining lifetime of a DHCP lease on the 1920 * address, or 1921 * 2. The remaining Valid Lifetime of a prefix from 1922 * which the address was derived through Stateless 1923 * Autoconfiguration. 1924 * 1925 * Note that we currently do not support stateful 1926 * address configuration by DHCPv6, so the former 1927 * case can't happen. 1928 */ 1929 if (ifa6->ia6_lifetime.ia6t_expire == 0) 1930 ltime = ND6_INFINITE_LIFETIME; 1931 else { 1932 if (ifa6->ia6_lifetime.ia6t_expire > 1933 time_uptime) 1934 ltime = htonl(ifa6->ia6_lifetime.ia6t_expire - time_uptime); 1935 else 1936 ltime = 0; 1937 } 1938 1939 bcopy(<ime, cp, sizeof(u_int32_t)); 1940 cp += sizeof(u_int32_t); 1941 1942 /* copy the address itself */ 1943 bcopy(&ifa6->ia_addr.sin6_addr, cp, 1944 sizeof(struct in6_addr)); 1945 in6_clearscope((struct in6_addr *)cp); /* XXX */ 1946 cp += sizeof(struct in6_addr); 1947 1948 resid -= (sizeof(struct in6_addr) + sizeof(u_int32_t)); 1949 copied += (sizeof(struct in6_addr) + sizeof(u_int32_t)); 1950 } 1951 IF_ADDR_RUNLOCK(ifp); 1952 if (ifp0) /* we need search only on the specified IF */ 1953 break; 1954 } 1955 1956 if (allow_deprecated == 0 && ifp_dep != NULL) { 1957 ifp = ifp_dep; 1958 allow_deprecated = 1; 1959 1960 goto again; 1961 } 1962 1963 IFNET_RUNLOCK_NOSLEEP(); 1964 1965 return (copied); 1966} 1967 1968/* 1969 * XXX almost dup'ed code with rip6_input. 1970 */ 1971static int 1972icmp6_rip6_input(struct mbuf **mp, int off) 1973{ 1974 struct mbuf *m = *mp; 1975 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1976 struct inpcb *in6p; 1977 struct inpcb *last = NULL; 1978 struct sockaddr_in6 fromsa; 1979 struct icmp6_hdr *icmp6; 1980 struct mbuf *opts = NULL; 1981 1982#ifndef PULLDOWN_TEST 1983 /* this is assumed to be safe. */ 1984 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off); 1985#else 1986 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 1987 if (icmp6 == NULL) { 1988 /* m is already reclaimed */ 1989 return (IPPROTO_DONE); 1990 } 1991#endif 1992 1993 /* 1994 * XXX: the address may have embedded scope zone ID, which should be 1995 * hidden from applications. 1996 */ 1997 bzero(&fromsa, sizeof(fromsa)); 1998 fromsa.sin6_family = AF_INET6; 1999 fromsa.sin6_len = sizeof(struct sockaddr_in6); 2000 fromsa.sin6_addr = ip6->ip6_src; 2001 if (sa6_recoverscope(&fromsa)) { 2002 m_freem(m); 2003 return (IPPROTO_DONE); 2004 } 2005 2006 INP_INFO_RLOCK(&V_ripcbinfo); 2007 LIST_FOREACH(in6p, &V_ripcb, inp_list) { 2008 if ((in6p->inp_vflag & INP_IPV6) == 0) 2009 continue; 2010 if (in6p->inp_ip_p != IPPROTO_ICMPV6) 2011 continue; 2012 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr) && 2013 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr, &ip6->ip6_dst)) 2014 continue; 2015 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr) && 2016 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr, &ip6->ip6_src)) 2017 continue; 2018 INP_RLOCK(in6p); 2019 if (ICMP6_FILTER_WILLBLOCK(icmp6->icmp6_type, 2020 in6p->in6p_icmp6filt)) { 2021 INP_RUNLOCK(in6p); 2022 continue; 2023 } 2024 if (last != NULL) { 2025 struct mbuf *n = NULL; 2026 2027 /* 2028 * Recent network drivers tend to allocate a single 2029 * mbuf cluster, rather than to make a couple of 2030 * mbufs without clusters. Also, since the IPv6 code 2031 * path tries to avoid m_pullup(), it is highly 2032 * probable that we still have an mbuf cluster here 2033 * even though the necessary length can be stored in an 2034 * mbuf's internal buffer. 2035 * Meanwhile, the default size of the receive socket 2036 * buffer for raw sockets is not so large. This means 2037 * the possibility of packet loss is relatively higher 2038 * than before. To avoid this scenario, we copy the 2039 * received data to a separate mbuf that does not use 2040 * a cluster, if possible. 2041 * XXX: it is better to copy the data after stripping 2042 * intermediate headers. 2043 */ 2044 if ((m->m_flags & M_EXT) && m->m_next == NULL && 2045 m->m_len <= MHLEN) { 2046 n = m_get(M_NOWAIT, m->m_type); 2047 if (n != NULL) { 2048 if (m_dup_pkthdr(n, m, M_NOWAIT)) { 2049 bcopy(m->m_data, n->m_data, 2050 m->m_len); 2051 n->m_len = m->m_len; 2052 } else { 2053 m_free(n); 2054 n = NULL; 2055 } 2056 } 2057 } 2058 if (n != NULL || 2059 (n = m_copy(m, 0, (int)M_COPYALL)) != NULL) { 2060 if (last->inp_flags & INP_CONTROLOPTS) 2061 ip6_savecontrol(last, n, &opts); 2062 /* strip intermediate headers */ 2063 m_adj(n, off); 2064 SOCKBUF_LOCK(&last->inp_socket->so_rcv); 2065 if (sbappendaddr_locked( 2066 &last->inp_socket->so_rcv, 2067 (struct sockaddr *)&fromsa, n, opts) 2068 == 0) { 2069 /* should notify about lost packet */ 2070 m_freem(n); 2071 if (opts) { 2072 m_freem(opts); 2073 } 2074 SOCKBUF_UNLOCK( 2075 &last->inp_socket->so_rcv); 2076 } else 2077 sorwakeup_locked(last->inp_socket); 2078 opts = NULL; 2079 } 2080 INP_RUNLOCK(last); 2081 } 2082 last = in6p; 2083 } 2084 INP_INFO_RUNLOCK(&V_ripcbinfo); 2085 if (last != NULL) { 2086 if (last->inp_flags & INP_CONTROLOPTS) 2087 ip6_savecontrol(last, m, &opts); 2088 /* strip intermediate headers */ 2089 m_adj(m, off); 2090 2091 /* avoid using mbuf clusters if possible (see above) */ 2092 if ((m->m_flags & M_EXT) && m->m_next == NULL && 2093 m->m_len <= MHLEN) { 2094 struct mbuf *n; 2095 2096 n = m_get(M_NOWAIT, m->m_type); 2097 if (n != NULL) { 2098 if (m_dup_pkthdr(n, m, M_NOWAIT)) { 2099 bcopy(m->m_data, n->m_data, m->m_len); 2100 n->m_len = m->m_len; 2101 2102 m_freem(m); 2103 m = n; 2104 } else { 2105 m_freem(n); 2106 n = NULL; 2107 } 2108 } 2109 } 2110 SOCKBUF_LOCK(&last->inp_socket->so_rcv); 2111 if (sbappendaddr_locked(&last->inp_socket->so_rcv, 2112 (struct sockaddr *)&fromsa, m, opts) == 0) { 2113 m_freem(m); 2114 if (opts) 2115 m_freem(opts); 2116 SOCKBUF_UNLOCK(&last->inp_socket->so_rcv); 2117 } else 2118 sorwakeup_locked(last->inp_socket); 2119 INP_RUNLOCK(last); 2120 } else { 2121 m_freem(m); 2122 IP6STAT_DEC(ip6s_delivered); 2123 } 2124 return IPPROTO_DONE; 2125} 2126 2127/* 2128 * Reflect the ip6 packet back to the source. 2129 * OFF points to the icmp6 header, counted from the top of the mbuf. 2130 */ 2131void 2132icmp6_reflect(struct mbuf *m, size_t off) 2133{ 2134 struct ip6_hdr *ip6; 2135 struct icmp6_hdr *icmp6; 2136 struct in6_ifaddr *ia = NULL; 2137 int plen; 2138 int type, code; 2139 struct ifnet *outif = NULL; 2140 struct in6_addr origdst, src, *srcp = NULL; 2141 2142 /* too short to reflect */ 2143 if (off < sizeof(struct ip6_hdr)) { 2144 nd6log((LOG_DEBUG, 2145 "sanity fail: off=%lx, sizeof(ip6)=%lx in %s:%d\n", 2146 (u_long)off, (u_long)sizeof(struct ip6_hdr), 2147 __FILE__, __LINE__)); 2148 goto bad; 2149 } 2150 2151 /* 2152 * If there are extra headers between IPv6 and ICMPv6, strip 2153 * off that header first. 2154 */ 2155#ifdef DIAGNOSTIC 2156 if (sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) > MHLEN) 2157 panic("assumption failed in icmp6_reflect"); 2158#endif 2159 if (off > sizeof(struct ip6_hdr)) { 2160 size_t l; 2161 struct ip6_hdr nip6; 2162 2163 l = off - sizeof(struct ip6_hdr); 2164 m_copydata(m, 0, sizeof(nip6), (caddr_t)&nip6); 2165 m_adj(m, l); 2166 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 2167 if (m->m_len < l) { 2168 if ((m = m_pullup(m, l)) == NULL) 2169 return; 2170 } 2171 bcopy((caddr_t)&nip6, mtod(m, caddr_t), sizeof(nip6)); 2172 } else /* off == sizeof(struct ip6_hdr) */ { 2173 size_t l; 2174 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 2175 if (m->m_len < l) { 2176 if ((m = m_pullup(m, l)) == NULL) 2177 return; 2178 } 2179 } 2180 plen = m->m_pkthdr.len - sizeof(struct ip6_hdr); 2181 ip6 = mtod(m, struct ip6_hdr *); 2182 ip6->ip6_nxt = IPPROTO_ICMPV6; 2183 icmp6 = (struct icmp6_hdr *)(ip6 + 1); 2184 type = icmp6->icmp6_type; /* keep type for statistics */ 2185 code = icmp6->icmp6_code; /* ditto. */ 2186 2187 origdst = ip6->ip6_dst; 2188 /* 2189 * ip6_input() drops a packet if its src is multicast. 2190 * So, the src is never multicast. 2191 */ 2192 ip6->ip6_dst = ip6->ip6_src; 2193 2194 /* 2195 * If the incoming packet was addressed directly to us (i.e. unicast), 2196 * use dst as the src for the reply. 2197 * The IN6_IFF_NOTREADY case should be VERY rare, but is possible 2198 * (for example) when we encounter an error while forwarding procedure 2199 * destined to a duplicated address of ours. 2200 * Note that ip6_getdstifaddr() may fail if we are in an error handling 2201 * procedure of an outgoing packet of our own, in which case we need 2202 * to search in the ifaddr list. 2203 */ 2204 if (!IN6_IS_ADDR_MULTICAST(&origdst)) { 2205 if ((ia = ip6_getdstifaddr(m))) { 2206 if (!(ia->ia6_flags & 2207 (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY))) 2208 srcp = &ia->ia_addr.sin6_addr; 2209 } else { 2210 struct sockaddr_in6 d; 2211 2212 bzero(&d, sizeof(d)); 2213 d.sin6_family = AF_INET6; 2214 d.sin6_len = sizeof(d); 2215 d.sin6_addr = origdst; 2216 ia = (struct in6_ifaddr *) 2217 ifa_ifwithaddr((struct sockaddr *)&d); 2218 if (ia && 2219 !(ia->ia6_flags & 2220 (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY))) { 2221 srcp = &ia->ia_addr.sin6_addr; 2222 } 2223 } 2224 } 2225 2226 if (srcp == NULL) { 2227 int e; 2228 struct sockaddr_in6 sin6; 2229 struct route_in6 ro; 2230 2231 /* 2232 * This case matches to multicasts, our anycast, or unicasts 2233 * that we do not own. Select a source address based on the 2234 * source address of the erroneous packet. 2235 */ 2236 bzero(&sin6, sizeof(sin6)); 2237 sin6.sin6_family = AF_INET6; 2238 sin6.sin6_len = sizeof(sin6); 2239 sin6.sin6_addr = ip6->ip6_dst; /* zone ID should be embedded */ 2240 2241 bzero(&ro, sizeof(ro)); 2242 e = in6_selectsrc(&sin6, NULL, NULL, &ro, NULL, &outif, &src); 2243 if (ro.ro_rt) 2244 RTFREE(ro.ro_rt); /* XXX: we could use this */ 2245 if (e) { 2246 char ip6buf[INET6_ADDRSTRLEN]; 2247 nd6log((LOG_DEBUG, 2248 "icmp6_reflect: source can't be determined: " 2249 "dst=%s, error=%d\n", 2250 ip6_sprintf(ip6buf, &sin6.sin6_addr), e)); 2251 goto bad; 2252 } 2253 srcp = &src; 2254 } 2255 2256 ip6->ip6_src = *srcp; 2257 ip6->ip6_flow = 0; 2258 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2259 ip6->ip6_vfc |= IPV6_VERSION; 2260 ip6->ip6_nxt = IPPROTO_ICMPV6; 2261 if (outif) 2262 ip6->ip6_hlim = ND_IFINFO(outif)->chlim; 2263 else if (m->m_pkthdr.rcvif) { 2264 /* XXX: This may not be the outgoing interface */ 2265 ip6->ip6_hlim = ND_IFINFO(m->m_pkthdr.rcvif)->chlim; 2266 } else 2267 ip6->ip6_hlim = V_ip6_defhlim; 2268 2269 icmp6->icmp6_cksum = 0; 2270 icmp6->icmp6_cksum = in6_cksum(m, IPPROTO_ICMPV6, 2271 sizeof(struct ip6_hdr), plen); 2272 2273 /* 2274 * XXX option handling 2275 */ 2276 2277 m->m_flags &= ~(M_BCAST|M_MCAST); 2278 2279 ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL); 2280 if (outif) 2281 icmp6_ifoutstat_inc(outif, type, code); 2282 2283 if (ia != NULL) 2284 ifa_free(&ia->ia_ifa); 2285 return; 2286 2287 bad: 2288 if (ia != NULL) 2289 ifa_free(&ia->ia_ifa); 2290 m_freem(m); 2291 return; 2292} 2293 2294void 2295icmp6_fasttimo(void) 2296{ 2297 2298 mld_fasttimo(); 2299} 2300 2301void 2302icmp6_slowtimo(void) 2303{ 2304 2305 mld_slowtimo(); 2306} 2307 2308static const char * 2309icmp6_redirect_diag(struct in6_addr *src6, struct in6_addr *dst6, 2310 struct in6_addr *tgt6) 2311{ 2312 static char buf[1024]; 2313 char ip6bufs[INET6_ADDRSTRLEN]; 2314 char ip6bufd[INET6_ADDRSTRLEN]; 2315 char ip6buft[INET6_ADDRSTRLEN]; 2316 snprintf(buf, sizeof(buf), "(src=%s dst=%s tgt=%s)", 2317 ip6_sprintf(ip6bufs, src6), ip6_sprintf(ip6bufd, dst6), 2318 ip6_sprintf(ip6buft, tgt6)); 2319 return buf; 2320} 2321 2322void 2323icmp6_redirect_input(struct mbuf *m, int off) 2324{ 2325 struct ifnet *ifp; 2326 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 2327 struct nd_redirect *nd_rd; 2328 int icmp6len = ntohs(ip6->ip6_plen); 2329 char *lladdr = NULL; 2330 int lladdrlen = 0; 2331 struct rtentry *rt = NULL; 2332 int is_router; 2333 int is_onlink; 2334 struct in6_addr src6 = ip6->ip6_src; 2335 struct in6_addr redtgt6; 2336 struct in6_addr reddst6; 2337 union nd_opts ndopts; 2338 char ip6buf[INET6_ADDRSTRLEN]; 2339 2340 M_ASSERTPKTHDR(m); 2341 KASSERT(m->m_pkthdr.rcvif != NULL, ("%s: no rcvif", __func__)); 2342 2343 ifp = m->m_pkthdr.rcvif; 2344 2345 /* XXX if we are router, we don't update route by icmp6 redirect */ 2346 if (V_ip6_forwarding) 2347 goto freeit; 2348 if (!V_icmp6_rediraccept) 2349 goto freeit; 2350 2351#ifndef PULLDOWN_TEST 2352 IP6_EXTHDR_CHECK(m, off, icmp6len,); 2353 nd_rd = (struct nd_redirect *)((caddr_t)ip6 + off); 2354#else 2355 IP6_EXTHDR_GET(nd_rd, struct nd_redirect *, m, off, icmp6len); 2356 if (nd_rd == NULL) { 2357 ICMP6STAT_INC(icp6s_tooshort); 2358 return; 2359 } 2360#endif 2361 redtgt6 = nd_rd->nd_rd_target; 2362 reddst6 = nd_rd->nd_rd_dst; 2363 2364 if (in6_setscope(&redtgt6, m->m_pkthdr.rcvif, NULL) || 2365 in6_setscope(&reddst6, m->m_pkthdr.rcvif, NULL)) { 2366 goto freeit; 2367 } 2368 2369 /* validation */ 2370 if (!IN6_IS_ADDR_LINKLOCAL(&src6)) { 2371 nd6log((LOG_ERR, 2372 "ICMP6 redirect sent from %s rejected; " 2373 "must be from linklocal\n", 2374 ip6_sprintf(ip6buf, &src6))); 2375 goto bad; 2376 } 2377 if (ip6->ip6_hlim != 255) { 2378 nd6log((LOG_ERR, 2379 "ICMP6 redirect sent from %s rejected; " 2380 "hlim=%d (must be 255)\n", 2381 ip6_sprintf(ip6buf, &src6), ip6->ip6_hlim)); 2382 goto bad; 2383 } 2384 { 2385 /* ip6->ip6_src must be equal to gw for icmp6->icmp6_reddst */ 2386 struct sockaddr_in6 sin6; 2387 struct in6_addr *gw6; 2388 2389 bzero(&sin6, sizeof(sin6)); 2390 sin6.sin6_family = AF_INET6; 2391 sin6.sin6_len = sizeof(struct sockaddr_in6); 2392 bcopy(&reddst6, &sin6.sin6_addr, sizeof(reddst6)); 2393 rt = in6_rtalloc1((struct sockaddr *)&sin6, 0, 0UL, RT_DEFAULT_FIB); 2394 if (rt) { 2395 if (rt->rt_gateway == NULL || 2396 rt->rt_gateway->sa_family != AF_INET6) { 2397 RTFREE_LOCKED(rt); 2398 nd6log((LOG_ERR, 2399 "ICMP6 redirect rejected; no route " 2400 "with inet6 gateway found for redirect dst: %s\n", 2401 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2402 goto bad; 2403 } 2404 2405 gw6 = &(((struct sockaddr_in6 *)rt->rt_gateway)->sin6_addr); 2406 if (bcmp(&src6, gw6, sizeof(struct in6_addr)) != 0) { 2407 RTFREE_LOCKED(rt); 2408 nd6log((LOG_ERR, 2409 "ICMP6 redirect rejected; " 2410 "not equal to gw-for-src=%s (must be same): " 2411 "%s\n", 2412 ip6_sprintf(ip6buf, gw6), 2413 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2414 goto bad; 2415 } 2416 } else { 2417 nd6log((LOG_ERR, 2418 "ICMP6 redirect rejected; " 2419 "no route found for redirect dst: %s\n", 2420 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2421 goto bad; 2422 } 2423 RTFREE_LOCKED(rt); 2424 rt = NULL; 2425 } 2426 if (IN6_IS_ADDR_MULTICAST(&reddst6)) { 2427 nd6log((LOG_ERR, 2428 "ICMP6 redirect rejected; " 2429 "redirect dst must be unicast: %s\n", 2430 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2431 goto bad; 2432 } 2433 2434 is_router = is_onlink = 0; 2435 if (IN6_IS_ADDR_LINKLOCAL(&redtgt6)) 2436 is_router = 1; /* router case */ 2437 if (bcmp(&redtgt6, &reddst6, sizeof(redtgt6)) == 0) 2438 is_onlink = 1; /* on-link destination case */ 2439 if (!is_router && !is_onlink) { 2440 nd6log((LOG_ERR, 2441 "ICMP6 redirect rejected; " 2442 "neither router case nor onlink case: %s\n", 2443 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2444 goto bad; 2445 } 2446 /* validation passed */ 2447 2448 icmp6len -= sizeof(*nd_rd); 2449 nd6_option_init(nd_rd + 1, icmp6len, &ndopts); 2450 if (nd6_options(&ndopts) < 0) { 2451 nd6log((LOG_INFO, "%s: invalid ND option, rejected: %s\n", 2452 __func__, icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2453 /* nd6_options have incremented stats */ 2454 goto freeit; 2455 } 2456 2457 if (ndopts.nd_opts_tgt_lladdr) { 2458 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 2459 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 2460 } 2461 2462 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 2463 nd6log((LOG_INFO, "%s: lladdrlen mismatch for %s " 2464 "(if %d, icmp6 packet %d): %s\n", 2465 __func__, ip6_sprintf(ip6buf, &redtgt6), 2466 ifp->if_addrlen, lladdrlen - 2, 2467 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2468 goto bad; 2469 } 2470 2471 /* RFC 2461 8.3 */ 2472 nd6_cache_lladdr(ifp, &redtgt6, lladdr, lladdrlen, ND_REDIRECT, 2473 is_onlink ? ND_REDIRECT_ONLINK : ND_REDIRECT_ROUTER); 2474 2475 if (!is_onlink) { /* better router case. perform rtredirect. */ 2476 /* perform rtredirect */ 2477 struct sockaddr_in6 sdst; 2478 struct sockaddr_in6 sgw; 2479 struct sockaddr_in6 ssrc; 2480 u_int fibnum; 2481 2482 bzero(&sdst, sizeof(sdst)); 2483 bzero(&sgw, sizeof(sgw)); 2484 bzero(&ssrc, sizeof(ssrc)); 2485 sdst.sin6_family = sgw.sin6_family = ssrc.sin6_family = AF_INET6; 2486 sdst.sin6_len = sgw.sin6_len = ssrc.sin6_len = 2487 sizeof(struct sockaddr_in6); 2488 bcopy(&redtgt6, &sgw.sin6_addr, sizeof(struct in6_addr)); 2489 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2490 bcopy(&src6, &ssrc.sin6_addr, sizeof(struct in6_addr)); 2491 for (fibnum = 0; fibnum < rt_numfibs; fibnum++) 2492 in6_rtredirect((struct sockaddr *)&sdst, 2493 (struct sockaddr *)&sgw, (struct sockaddr *)NULL, 2494 RTF_GATEWAY | RTF_HOST, (struct sockaddr *)&ssrc, 2495 fibnum); 2496 } 2497 /* finally update cached route in each socket via pfctlinput */ 2498 { 2499 struct sockaddr_in6 sdst; 2500 2501 bzero(&sdst, sizeof(sdst)); 2502 sdst.sin6_family = AF_INET6; 2503 sdst.sin6_len = sizeof(struct sockaddr_in6); 2504 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2505 pfctlinput(PRC_REDIRECT_HOST, (struct sockaddr *)&sdst); 2506#ifdef IPSEC 2507 key_sa_routechange((struct sockaddr *)&sdst); 2508#endif /* IPSEC */ 2509 } 2510 2511 freeit: 2512 m_freem(m); 2513 return; 2514 2515 bad: 2516 ICMP6STAT_INC(icp6s_badredirect); 2517 m_freem(m); 2518} 2519 2520void 2521icmp6_redirect_output(struct mbuf *m0, struct rtentry *rt) 2522{ 2523 struct ifnet *ifp; /* my outgoing interface */ 2524 struct in6_addr *ifp_ll6; 2525 struct in6_addr *router_ll6; 2526 struct ip6_hdr *sip6; /* m0 as struct ip6_hdr */ 2527 struct mbuf *m = NULL; /* newly allocated one */ 2528 struct m_tag *mtag; 2529 struct ip6_hdr *ip6; /* m as struct ip6_hdr */ 2530 struct nd_redirect *nd_rd; 2531 struct llentry *ln = NULL; 2532 size_t maxlen; 2533 u_char *p; 2534 struct ifnet *outif = NULL; 2535 struct sockaddr_in6 src_sa; 2536 2537 icmp6_errcount(ND_REDIRECT, 0); 2538 2539 /* if we are not router, we don't send icmp6 redirect */ 2540 if (!V_ip6_forwarding) 2541 goto fail; 2542 2543 /* sanity check */ 2544 if (!m0 || !rt || !(rt->rt_flags & RTF_UP) || !(ifp = rt->rt_ifp)) 2545 goto fail; 2546 2547 /* 2548 * Address check: 2549 * the source address must identify a neighbor, and 2550 * the destination address must not be a multicast address 2551 * [RFC 2461, sec 8.2] 2552 */ 2553 sip6 = mtod(m0, struct ip6_hdr *); 2554 bzero(&src_sa, sizeof(src_sa)); 2555 src_sa.sin6_family = AF_INET6; 2556 src_sa.sin6_len = sizeof(src_sa); 2557 src_sa.sin6_addr = sip6->ip6_src; 2558 if (nd6_is_addr_neighbor(&src_sa, ifp) == 0) 2559 goto fail; 2560 if (IN6_IS_ADDR_MULTICAST(&sip6->ip6_dst)) 2561 goto fail; /* what should we do here? */ 2562 2563 /* rate limit */ 2564 if (icmp6_ratelimit(&sip6->ip6_src, ND_REDIRECT, 0)) 2565 goto fail; 2566 2567 /* 2568 * Since we are going to append up to 1280 bytes (= IPV6_MMTU), 2569 * we almost always ask for an mbuf cluster for simplicity. 2570 * (MHLEN < IPV6_MMTU is almost always true) 2571 */ 2572#if IPV6_MMTU >= MCLBYTES 2573# error assumption failed about IPV6_MMTU and MCLBYTES 2574#endif 2575 m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR); 2576 if (m == NULL) 2577 goto fail; 2578 M_SETFIB(m, rt->rt_fibnum); 2579 maxlen = M_TRAILINGSPACE(m); 2580 maxlen = min(IPV6_MMTU, maxlen); 2581 /* just for safety */ 2582 if (maxlen < sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) + 2583 ((sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7)) { 2584 goto fail; 2585 } 2586 2587 { 2588 /* get ip6 linklocal address for ifp(my outgoing interface). */ 2589 struct in6_ifaddr *ia; 2590 if ((ia = in6ifa_ifpforlinklocal(ifp, 2591 IN6_IFF_NOTREADY| 2592 IN6_IFF_ANYCAST)) == NULL) 2593 goto fail; 2594 ifp_ll6 = &ia->ia_addr.sin6_addr; 2595 /* XXXRW: reference released prematurely. */ 2596 ifa_free(&ia->ia_ifa); 2597 } 2598 2599 /* get ip6 linklocal address for the router. */ 2600 if (rt->rt_gateway && (rt->rt_flags & RTF_GATEWAY)) { 2601 struct sockaddr_in6 *sin6; 2602 sin6 = (struct sockaddr_in6 *)rt->rt_gateway; 2603 router_ll6 = &sin6->sin6_addr; 2604 if (!IN6_IS_ADDR_LINKLOCAL(router_ll6)) 2605 router_ll6 = (struct in6_addr *)NULL; 2606 } else 2607 router_ll6 = (struct in6_addr *)NULL; 2608 2609 /* ip6 */ 2610 ip6 = mtod(m, struct ip6_hdr *); 2611 ip6->ip6_flow = 0; 2612 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2613 ip6->ip6_vfc |= IPV6_VERSION; 2614 /* ip6->ip6_plen will be set later */ 2615 ip6->ip6_nxt = IPPROTO_ICMPV6; 2616 ip6->ip6_hlim = 255; 2617 /* ip6->ip6_src must be linklocal addr for my outgoing if. */ 2618 bcopy(ifp_ll6, &ip6->ip6_src, sizeof(struct in6_addr)); 2619 bcopy(&sip6->ip6_src, &ip6->ip6_dst, sizeof(struct in6_addr)); 2620 2621 /* ND Redirect */ 2622 nd_rd = (struct nd_redirect *)(ip6 + 1); 2623 nd_rd->nd_rd_type = ND_REDIRECT; 2624 nd_rd->nd_rd_code = 0; 2625 nd_rd->nd_rd_reserved = 0; 2626 if (rt->rt_flags & RTF_GATEWAY) { 2627 /* 2628 * nd_rd->nd_rd_target must be a link-local address in 2629 * better router cases. 2630 */ 2631 if (!router_ll6) 2632 goto fail; 2633 bcopy(router_ll6, &nd_rd->nd_rd_target, 2634 sizeof(nd_rd->nd_rd_target)); 2635 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2636 sizeof(nd_rd->nd_rd_dst)); 2637 } else { 2638 /* make sure redtgt == reddst */ 2639 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_target, 2640 sizeof(nd_rd->nd_rd_target)); 2641 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2642 sizeof(nd_rd->nd_rd_dst)); 2643 } 2644 2645 p = (u_char *)(nd_rd + 1); 2646 2647 if (!router_ll6) 2648 goto nolladdropt; 2649 2650 { 2651 /* target lladdr option */ 2652 int len; 2653 struct nd_opt_hdr *nd_opt; 2654 char *lladdr; 2655 2656 IF_AFDATA_RLOCK(ifp); 2657 ln = nd6_lookup(router_ll6, 0, ifp); 2658 IF_AFDATA_RUNLOCK(ifp); 2659 if (ln == NULL) 2660 goto nolladdropt; 2661 2662 len = sizeof(*nd_opt) + ifp->if_addrlen; 2663 len = (len + 7) & ~7; /* round by 8 */ 2664 /* safety check */ 2665 if (len + (p - (u_char *)ip6) > maxlen) 2666 goto nolladdropt; 2667 2668 if (ln->la_flags & LLE_VALID) { 2669 nd_opt = (struct nd_opt_hdr *)p; 2670 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 2671 nd_opt->nd_opt_len = len >> 3; 2672 lladdr = (char *)(nd_opt + 1); 2673 bcopy(&ln->ll_addr, lladdr, ifp->if_addrlen); 2674 p += len; 2675 } 2676 } 2677nolladdropt: 2678 if (ln != NULL) 2679 LLE_RUNLOCK(ln); 2680 2681 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2682 2683 /* just to be safe */ 2684#ifdef M_DECRYPTED /*not openbsd*/ 2685 if (m0->m_flags & M_DECRYPTED) 2686 goto noredhdropt; 2687#endif 2688 if (p - (u_char *)ip6 > maxlen) 2689 goto noredhdropt; 2690 2691 { 2692 /* redirected header option */ 2693 int len; 2694 struct nd_opt_rd_hdr *nd_opt_rh; 2695 2696 /* 2697 * compute the maximum size for icmp6 redirect header option. 2698 * XXX room for auth header? 2699 */ 2700 len = maxlen - (p - (u_char *)ip6); 2701 len &= ~7; 2702 2703 /* This is just for simplicity. */ 2704 if (m0->m_pkthdr.len != m0->m_len) { 2705 if (m0->m_next) { 2706 m_freem(m0->m_next); 2707 m0->m_next = NULL; 2708 } 2709 m0->m_pkthdr.len = m0->m_len; 2710 } 2711 2712 /* 2713 * Redirected header option spec (RFC2461 4.6.3) talks nothing 2714 * about padding/truncate rule for the original IP packet. 2715 * From the discussion on IPv6imp in Feb 1999, 2716 * the consensus was: 2717 * - "attach as much as possible" is the goal 2718 * - pad if not aligned (original size can be guessed by 2719 * original ip6 header) 2720 * Following code adds the padding if it is simple enough, 2721 * and truncates if not. 2722 */ 2723 if (m0->m_next || m0->m_pkthdr.len != m0->m_len) 2724 panic("assumption failed in %s:%d", __FILE__, 2725 __LINE__); 2726 2727 if (len - sizeof(*nd_opt_rh) < m0->m_pkthdr.len) { 2728 /* not enough room, truncate */ 2729 m0->m_pkthdr.len = m0->m_len = len - 2730 sizeof(*nd_opt_rh); 2731 } else { 2732 /* enough room, pad or truncate */ 2733 size_t extra; 2734 2735 extra = m0->m_pkthdr.len % 8; 2736 if (extra) { 2737 /* pad if easy enough, truncate if not */ 2738 if (8 - extra <= M_TRAILINGSPACE(m0)) { 2739 /* pad */ 2740 m0->m_len += (8 - extra); 2741 m0->m_pkthdr.len += (8 - extra); 2742 } else { 2743 /* truncate */ 2744 m0->m_pkthdr.len -= extra; 2745 m0->m_len -= extra; 2746 } 2747 } 2748 len = m0->m_pkthdr.len + sizeof(*nd_opt_rh); 2749 m0->m_pkthdr.len = m0->m_len = len - 2750 sizeof(*nd_opt_rh); 2751 } 2752 2753 nd_opt_rh = (struct nd_opt_rd_hdr *)p; 2754 bzero(nd_opt_rh, sizeof(*nd_opt_rh)); 2755 nd_opt_rh->nd_opt_rh_type = ND_OPT_REDIRECTED_HEADER; 2756 nd_opt_rh->nd_opt_rh_len = len >> 3; 2757 p += sizeof(*nd_opt_rh); 2758 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2759 2760 /* connect m0 to m */ 2761 m_tag_delete_chain(m0, NULL); 2762 m0->m_flags &= ~M_PKTHDR; 2763 m->m_next = m0; 2764 m->m_pkthdr.len = m->m_len + m0->m_len; 2765 m0 = NULL; 2766 } 2767noredhdropt:; 2768 if (m0) { 2769 m_freem(m0); 2770 m0 = NULL; 2771 } 2772 2773 /* XXX: clear embedded link IDs in the inner header */ 2774 in6_clearscope(&sip6->ip6_src); 2775 in6_clearscope(&sip6->ip6_dst); 2776 in6_clearscope(&nd_rd->nd_rd_target); 2777 in6_clearscope(&nd_rd->nd_rd_dst); 2778 2779 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr)); 2780 2781 nd_rd->nd_rd_cksum = 0; 2782 nd_rd->nd_rd_cksum = in6_cksum(m, IPPROTO_ICMPV6, 2783 sizeof(*ip6), ntohs(ip6->ip6_plen)); 2784 2785 if (send_sendso_input_hook != NULL) { 2786 mtag = m_tag_get(PACKET_TAG_ND_OUTGOING, sizeof(unsigned short), 2787 M_NOWAIT); 2788 if (mtag == NULL) 2789 goto fail; 2790 *(unsigned short *)(mtag + 1) = nd_rd->nd_rd_type; 2791 m_tag_prepend(m, mtag); 2792 } 2793 2794 /* send the packet to outside... */ 2795 ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL); 2796 if (outif) { 2797 icmp6_ifstat_inc(outif, ifs6_out_msg); 2798 icmp6_ifstat_inc(outif, ifs6_out_redirect); 2799 } 2800 ICMP6STAT_INC(icp6s_outhist[ND_REDIRECT]); 2801 2802 return; 2803 2804fail: 2805 if (m) 2806 m_freem(m); 2807 if (m0) 2808 m_freem(m0); 2809} 2810 2811/* 2812 * ICMPv6 socket option processing. 2813 */ 2814int 2815icmp6_ctloutput(struct socket *so, struct sockopt *sopt) 2816{ 2817 int error = 0; 2818 int optlen; 2819 struct inpcb *inp = sotoinpcb(so); 2820 int level, op, optname; 2821 2822 if (sopt) { 2823 level = sopt->sopt_level; 2824 op = sopt->sopt_dir; 2825 optname = sopt->sopt_name; 2826 optlen = sopt->sopt_valsize; 2827 } else 2828 level = op = optname = optlen = 0; 2829 2830 if (level != IPPROTO_ICMPV6) { 2831 return EINVAL; 2832 } 2833 2834 switch (op) { 2835 case PRCO_SETOPT: 2836 switch (optname) { 2837 case ICMP6_FILTER: 2838 { 2839 struct icmp6_filter ic6f; 2840 2841 if (optlen != sizeof(ic6f)) { 2842 error = EMSGSIZE; 2843 break; 2844 } 2845 error = sooptcopyin(sopt, &ic6f, optlen, optlen); 2846 if (error == 0) { 2847 INP_WLOCK(inp); 2848 *inp->in6p_icmp6filt = ic6f; 2849 INP_WUNLOCK(inp); 2850 } 2851 break; 2852 } 2853 2854 default: 2855 error = ENOPROTOOPT; 2856 break; 2857 } 2858 break; 2859 2860 case PRCO_GETOPT: 2861 switch (optname) { 2862 case ICMP6_FILTER: 2863 { 2864 struct icmp6_filter ic6f; 2865 2866 INP_RLOCK(inp); 2867 ic6f = *inp->in6p_icmp6filt; 2868 INP_RUNLOCK(inp); 2869 error = sooptcopyout(sopt, &ic6f, sizeof(ic6f)); 2870 break; 2871 } 2872 2873 default: 2874 error = ENOPROTOOPT; 2875 break; 2876 } 2877 break; 2878 } 2879 2880 return (error); 2881} 2882 2883/* 2884 * Perform rate limit check. 2885 * Returns 0 if it is okay to send the icmp6 packet. 2886 * Returns 1 if the router SHOULD NOT send this icmp6 packet due to rate 2887 * limitation. 2888 * 2889 * XXX per-destination/type check necessary? 2890 * 2891 * dst - not used at this moment 2892 * type - not used at this moment 2893 * code - not used at this moment 2894 */ 2895static int 2896icmp6_ratelimit(const struct in6_addr *dst, const int type, 2897 const int code) 2898{ 2899 int ret; 2900 2901 ret = 0; /* okay to send */ 2902 2903 /* PPS limit */ 2904 if (!ppsratecheck(&V_icmp6errppslim_last, &V_icmp6errpps_count, 2905 V_icmp6errppslim)) { 2906 /* The packet is subject to rate limit */ 2907 ret++; 2908 } 2909 2910 return ret; 2911} 2912