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 69#include <sys/param.h> 70#include <sys/domain.h> 71#include <sys/jail.h> 72#include <sys/kernel.h> 73#include <sys/lock.h> 74#include <sys/malloc.h> 75#include <sys/mbuf.h> 76#include <sys/proc.h> 77#include <sys/protosw.h> 78#include <sys/signalvar.h> 79#include <sys/socket.h> 80#include <sys/socketvar.h> 81#include <sys/sx.h> 82#include <sys/syslog.h> 83#include <sys/systm.h> 84#include <sys/time.h> 85 86#include <net/if.h> 87#include <net/if_dl.h> 88#include <net/if_llatbl.h> 89#include <net/if_types.h> 90#include <net/route.h> 91#include <net/vnet.h> 92 93#include <netinet/in.h> 94#include <netinet/in_pcb.h> 95#include <netinet/in_var.h> 96#include <netinet/ip6.h> 97#include <netinet/icmp6.h> 98#include <netinet/tcp_var.h> 99 100#include <netinet6/in6_ifattach.h> 101#include <netinet6/in6_pcb.h> 102#include <netinet6/ip6protosw.h> 103#include <netinet6/ip6_var.h> 104#include <netinet6/scope6_var.h> 105#include <netinet6/mld6_var.h> 106#include <netinet6/nd6.h> 107#include <netinet6/send.h> 108 109extern struct domain inet6domain; 110 111VNET_PCPUSTAT_DEFINE(struct icmp6stat, icmp6stat); 112VNET_PCPUSTAT_SYSINIT(icmp6stat); 113 114#ifdef VIMAGE 115VNET_PCPUSTAT_SYSUNINIT(icmp6stat); 116#endif /* VIMAGE */ 117 118VNET_DECLARE(struct inpcbinfo, ripcbinfo); 119VNET_DECLARE(struct inpcbhead, ripcb); 120VNET_DECLARE(int, icmp6errppslim); 121static VNET_DEFINE(int, icmp6errpps_count) = 0; 122static VNET_DEFINE(struct timeval, icmp6errppslim_last); 123VNET_DECLARE(int, icmp6_nodeinfo); 124 125#define V_ripcbinfo VNET(ripcbinfo) 126#define V_ripcb VNET(ripcb) 127#define V_icmp6errppslim VNET(icmp6errppslim) 128#define V_icmp6errpps_count VNET(icmp6errpps_count) 129#define V_icmp6errppslim_last VNET(icmp6errppslim_last) 130#define V_icmp6_nodeinfo VNET(icmp6_nodeinfo) 131 132static void icmp6_errcount(int, int); 133static int icmp6_rip6_input(struct mbuf **, int); 134static int icmp6_ratelimit(const struct in6_addr *, const int, const int); 135static const char *icmp6_redirect_diag(struct in6_addr *, 136 struct in6_addr *, struct in6_addr *); 137static struct mbuf *ni6_input(struct mbuf *, int); 138static struct mbuf *ni6_nametodns(const char *, int, int); 139static int ni6_dnsmatch(const char *, int, const char *, int); 140static int ni6_addrs(struct icmp6_nodeinfo *, struct mbuf *, 141 struct ifnet **, struct in6_addr *); 142static int ni6_store_addrs(struct icmp6_nodeinfo *, struct icmp6_nodeinfo *, 143 struct ifnet *, int); 144static int icmp6_notify_error(struct mbuf **, int, int, int); 145 146/* 147 * Kernel module interface for updating icmp6stat. The argument is an index 148 * into icmp6stat treated as an array of u_quad_t. While this encodes the 149 * general layout of icmp6stat into the caller, it doesn't encode its 150 * location, so that future changes to add, for example, per-CPU stats 151 * support won't cause binary compatibility problems for kernel modules. 152 */ 153void 154kmod_icmp6stat_inc(int statnum) 155{ 156 157 counter_u64_add(VNET(icmp6stat)[statnum], 1); 158} 159 160static void 161icmp6_errcount(int type, int code) 162{ 163 switch (type) { 164 case ICMP6_DST_UNREACH: 165 switch (code) { 166 case ICMP6_DST_UNREACH_NOROUTE: 167 ICMP6STAT_INC(icp6s_odst_unreach_noroute); 168 return; 169 case ICMP6_DST_UNREACH_ADMIN: 170 ICMP6STAT_INC(icp6s_odst_unreach_admin); 171 return; 172 case ICMP6_DST_UNREACH_BEYONDSCOPE: 173 ICMP6STAT_INC(icp6s_odst_unreach_beyondscope); 174 return; 175 case ICMP6_DST_UNREACH_ADDR: 176 ICMP6STAT_INC(icp6s_odst_unreach_addr); 177 return; 178 case ICMP6_DST_UNREACH_NOPORT: 179 ICMP6STAT_INC(icp6s_odst_unreach_noport); 180 return; 181 } 182 break; 183 case ICMP6_PACKET_TOO_BIG: 184 ICMP6STAT_INC(icp6s_opacket_too_big); 185 return; 186 case ICMP6_TIME_EXCEEDED: 187 switch (code) { 188 case ICMP6_TIME_EXCEED_TRANSIT: 189 ICMP6STAT_INC(icp6s_otime_exceed_transit); 190 return; 191 case ICMP6_TIME_EXCEED_REASSEMBLY: 192 ICMP6STAT_INC(icp6s_otime_exceed_reassembly); 193 return; 194 } 195 break; 196 case ICMP6_PARAM_PROB: 197 switch (code) { 198 case ICMP6_PARAMPROB_HEADER: 199 ICMP6STAT_INC(icp6s_oparamprob_header); 200 return; 201 case ICMP6_PARAMPROB_NEXTHEADER: 202 ICMP6STAT_INC(icp6s_oparamprob_nextheader); 203 return; 204 case ICMP6_PARAMPROB_OPTION: 205 ICMP6STAT_INC(icp6s_oparamprob_option); 206 return; 207 } 208 break; 209 case ND_REDIRECT: 210 ICMP6STAT_INC(icp6s_oredirect); 211 return; 212 } 213 ICMP6STAT_INC(icp6s_ounknown); 214} 215 216/* 217 * A wrapper function for icmp6_error() necessary when the erroneous packet 218 * may not contain enough scope zone information. 219 */ 220void 221icmp6_error2(struct mbuf *m, int type, int code, int param, 222 struct ifnet *ifp) 223{ 224 struct ip6_hdr *ip6; 225 226 if (ifp == NULL) 227 return; 228 229#ifndef PULLDOWN_TEST 230 IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), ); 231#else 232 if (m->m_len < sizeof(struct ip6_hdr)) { 233 m = m_pullup(m, sizeof(struct ip6_hdr)); 234 if (m == NULL) 235 return; 236 } 237#endif 238 239 ip6 = mtod(m, struct ip6_hdr *); 240 241 if (in6_setscope(&ip6->ip6_src, ifp, NULL) != 0) 242 return; 243 if (in6_setscope(&ip6->ip6_dst, ifp, NULL) != 0) 244 return; 245 246 icmp6_error(m, type, code, param); 247} 248 249/* 250 * Generate an error packet of type error in response to bad IP6 packet. 251 */ 252void 253icmp6_error(struct mbuf *m, int type, int code, int param) 254{ 255 struct ip6_hdr *oip6, *nip6; 256 struct icmp6_hdr *icmp6; 257 u_int preplen; 258 int off; 259 int nxt; 260 261 ICMP6STAT_INC(icp6s_error); 262 263 /* count per-type-code statistics */ 264 icmp6_errcount(type, code); 265 266#ifdef M_DECRYPTED /*not openbsd*/ 267 if (m->m_flags & M_DECRYPTED) { 268 ICMP6STAT_INC(icp6s_canterror); 269 goto freeit; 270 } 271#endif 272 273#ifndef PULLDOWN_TEST 274 IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), ); 275#else 276 if (m->m_len < sizeof(struct ip6_hdr)) { 277 m = m_pullup(m, sizeof(struct ip6_hdr)); 278 if (m == NULL) 279 return; 280 } 281#endif 282 oip6 = mtod(m, struct ip6_hdr *); 283 284 /* 285 * If the destination address of the erroneous packet is a multicast 286 * address, or the packet was sent using link-layer multicast, 287 * we should basically suppress sending an error (RFC 2463, Section 288 * 2.4). 289 * We have two exceptions (the item e.2 in that section): 290 * - the Packet Too Big message can be sent for path MTU discovery. 291 * - the Parameter Problem Message that can be allowed an icmp6 error 292 * in the option type field. This check has been done in 293 * ip6_unknown_opt(), so we can just check the type and code. 294 */ 295 if ((m->m_flags & (M_BCAST|M_MCAST) || 296 IN6_IS_ADDR_MULTICAST(&oip6->ip6_dst)) && 297 (type != ICMP6_PACKET_TOO_BIG && 298 (type != ICMP6_PARAM_PROB || 299 code != ICMP6_PARAMPROB_OPTION))) 300 goto freeit; 301 302 /* 303 * RFC 2463, 2.4 (e.5): source address check. 304 * XXX: the case of anycast source? 305 */ 306 if (IN6_IS_ADDR_UNSPECIFIED(&oip6->ip6_src) || 307 IN6_IS_ADDR_MULTICAST(&oip6->ip6_src)) 308 goto freeit; 309 310 /* 311 * If we are about to send ICMPv6 against ICMPv6 error/redirect, 312 * don't do it. 313 */ 314 nxt = -1; 315 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); 316 if (off >= 0 && nxt == IPPROTO_ICMPV6) { 317 struct icmp6_hdr *icp; 318 319#ifndef PULLDOWN_TEST 320 IP6_EXTHDR_CHECK(m, 0, off + sizeof(struct icmp6_hdr), ); 321 icp = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 322#else 323 IP6_EXTHDR_GET(icp, struct icmp6_hdr *, m, off, 324 sizeof(*icp)); 325 if (icp == NULL) { 326 ICMP6STAT_INC(icp6s_tooshort); 327 return; 328 } 329#endif 330 if (icp->icmp6_type < ICMP6_ECHO_REQUEST || 331 icp->icmp6_type == ND_REDIRECT) { 332 /* 333 * ICMPv6 error 334 * Special case: for redirect (which is 335 * informational) we must not send icmp6 error. 336 */ 337 ICMP6STAT_INC(icp6s_canterror); 338 goto freeit; 339 } else { 340 /* ICMPv6 informational - send the error */ 341 } 342 } else { 343 /* non-ICMPv6 - send the error */ 344 } 345 346 oip6 = mtod(m, struct ip6_hdr *); /* adjust pointer */ 347 348 /* Finally, do rate limitation check. */ 349 if (icmp6_ratelimit(&oip6->ip6_src, type, code)) { 350 ICMP6STAT_INC(icp6s_toofreq); 351 goto freeit; 352 } 353 354 /* 355 * OK, ICMP6 can be generated. 356 */ 357 358 if (m->m_pkthdr.len >= ICMPV6_PLD_MAXLEN) 359 m_adj(m, ICMPV6_PLD_MAXLEN - m->m_pkthdr.len); 360 361 preplen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 362 M_PREPEND(m, preplen, M_NOWAIT); /* FIB is also copied over. */ 363 if (m == NULL) { 364 nd6log((LOG_DEBUG, "ENOBUFS in icmp6_error %d\n", __LINE__)); 365 return; 366 } 367 368 nip6 = mtod(m, struct ip6_hdr *); 369 nip6->ip6_src = oip6->ip6_src; 370 nip6->ip6_dst = oip6->ip6_dst; 371 372 in6_clearscope(&oip6->ip6_src); 373 in6_clearscope(&oip6->ip6_dst); 374 375 icmp6 = (struct icmp6_hdr *)(nip6 + 1); 376 icmp6->icmp6_type = type; 377 icmp6->icmp6_code = code; 378 icmp6->icmp6_pptr = htonl((u_int32_t)param); 379 380 /* 381 * icmp6_reflect() is designed to be in the input path. 382 * icmp6_error() can be called from both input and output path, 383 * and if we are in output path rcvif could contain bogus value. 384 * clear m->m_pkthdr.rcvif for safety, we should have enough scope 385 * information in ip header (nip6). 386 */ 387 m->m_pkthdr.rcvif = NULL; 388 389 ICMP6STAT_INC(icp6s_outhist[type]); 390 icmp6_reflect(m, sizeof(struct ip6_hdr)); /* header order: IPv6 - ICMPv6 */ 391 392 return; 393 394 freeit: 395 /* 396 * If we can't tell whether or not we can generate ICMP6, free it. 397 */ 398 m_freem(m); 399} 400 401/* 402 * Process a received ICMP6 message. 403 */ 404int 405icmp6_input(struct mbuf **mp, int *offp, int proto) 406{ 407 struct mbuf *m = *mp, *n; 408 struct ifnet *ifp; 409 struct ip6_hdr *ip6, *nip6; 410 struct icmp6_hdr *icmp6, *nicmp6; 411 int off = *offp; 412 int icmp6len = m->m_pkthdr.len - *offp; 413 int code, sum, noff; 414 char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN]; 415 int ip6len, error; 416 417 ifp = m->m_pkthdr.rcvif; 418 419#ifndef PULLDOWN_TEST 420 IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_hdr), IPPROTO_DONE); 421 /* m might change if M_LOOP. So, call mtod after this */ 422#endif 423 424 /* 425 * Locate icmp6 structure in mbuf, and check 426 * that not corrupted and of at least minimum length 427 */ 428 429 ip6 = mtod(m, struct ip6_hdr *); 430 ip6len = sizeof(struct ip6_hdr) + ntohs(ip6->ip6_plen); 431 if (icmp6len < sizeof(struct icmp6_hdr)) { 432 ICMP6STAT_INC(icp6s_tooshort); 433 goto freeit; 434 } 435 436 /* 437 * Check multicast group membership. 438 * Note: SSM filters are not applied for ICMPv6 traffic. 439 */ 440 if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) { 441 struct in6_multi *inm; 442 443 inm = in6m_lookup(ifp, &ip6->ip6_dst); 444 if (inm == NULL) { 445 IP6STAT_INC(ip6s_notmember); 446 in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_discard); 447 goto freeit; 448 } 449 } 450 451 /* 452 * calculate the checksum 453 */ 454#ifndef PULLDOWN_TEST 455 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off); 456#else 457 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 458 if (icmp6 == NULL) { 459 ICMP6STAT_INC(icp6s_tooshort); 460 return IPPROTO_DONE; 461 } 462#endif 463 code = icmp6->icmp6_code; 464 465 if ((sum = in6_cksum(m, IPPROTO_ICMPV6, off, icmp6len)) != 0) { 466 nd6log((LOG_ERR, 467 "ICMP6 checksum error(%d|%x) %s\n", 468 icmp6->icmp6_type, sum, 469 ip6_sprintf(ip6bufs, &ip6->ip6_src))); 470 ICMP6STAT_INC(icp6s_checksum); 471 goto freeit; 472 } 473 474 if (faithprefix_p != NULL && (*faithprefix_p)(&ip6->ip6_dst)) { 475 /* 476 * Deliver very specific ICMP6 type only. 477 * This is important to deliver TOOBIG. Otherwise PMTUD 478 * will not work. 479 */ 480 switch (icmp6->icmp6_type) { 481 case ICMP6_DST_UNREACH: 482 case ICMP6_PACKET_TOO_BIG: 483 case ICMP6_TIME_EXCEEDED: 484 break; 485 default: 486 goto freeit; 487 } 488 } 489 490 ICMP6STAT_INC(icp6s_inhist[icmp6->icmp6_type]); 491 icmp6_ifstat_inc(ifp, ifs6_in_msg); 492 if (icmp6->icmp6_type < ICMP6_INFOMSG_MASK) 493 icmp6_ifstat_inc(ifp, ifs6_in_error); 494 495 switch (icmp6->icmp6_type) { 496 case ICMP6_DST_UNREACH: 497 icmp6_ifstat_inc(ifp, ifs6_in_dstunreach); 498 switch (code) { 499 case ICMP6_DST_UNREACH_NOROUTE: 500 code = PRC_UNREACH_NET; 501 break; 502 case ICMP6_DST_UNREACH_ADMIN: 503 icmp6_ifstat_inc(ifp, ifs6_in_adminprohib); 504 code = PRC_UNREACH_PROTOCOL; /* is this a good code? */ 505 break; 506 case ICMP6_DST_UNREACH_ADDR: 507 code = PRC_HOSTDEAD; 508 break; 509 case ICMP6_DST_UNREACH_BEYONDSCOPE: 510 /* I mean "source address was incorrect." */ 511 code = PRC_PARAMPROB; 512 break; 513 case ICMP6_DST_UNREACH_NOPORT: 514 code = PRC_UNREACH_PORT; 515 break; 516 default: 517 goto badcode; 518 } 519 goto deliver; 520 break; 521 522 case ICMP6_PACKET_TOO_BIG: 523 icmp6_ifstat_inc(ifp, ifs6_in_pkttoobig); 524 525 /* validation is made in icmp6_mtudisc_update */ 526 527 code = PRC_MSGSIZE; 528 529 /* 530 * Updating the path MTU will be done after examining 531 * intermediate extension headers. 532 */ 533 goto deliver; 534 break; 535 536 case ICMP6_TIME_EXCEEDED: 537 icmp6_ifstat_inc(ifp, ifs6_in_timeexceed); 538 switch (code) { 539 case ICMP6_TIME_EXCEED_TRANSIT: 540 code = PRC_TIMXCEED_INTRANS; 541 break; 542 case ICMP6_TIME_EXCEED_REASSEMBLY: 543 code = PRC_TIMXCEED_REASS; 544 break; 545 default: 546 goto badcode; 547 } 548 goto deliver; 549 break; 550 551 case ICMP6_PARAM_PROB: 552 icmp6_ifstat_inc(ifp, ifs6_in_paramprob); 553 switch (code) { 554 case ICMP6_PARAMPROB_NEXTHEADER: 555 code = PRC_UNREACH_PROTOCOL; 556 break; 557 case ICMP6_PARAMPROB_HEADER: 558 case ICMP6_PARAMPROB_OPTION: 559 code = PRC_PARAMPROB; 560 break; 561 default: 562 goto badcode; 563 } 564 goto deliver; 565 break; 566 567 case ICMP6_ECHO_REQUEST: 568 icmp6_ifstat_inc(ifp, ifs6_in_echo); 569 if (code != 0) 570 goto badcode; 571 if ((n = m_copy(m, 0, M_COPYALL)) == NULL) { 572 /* Give up remote */ 573 break; 574 } 575 if ((n->m_flags & M_EXT) != 0 576 || n->m_len < off + sizeof(struct icmp6_hdr)) { 577 struct mbuf *n0 = n; 578 int n0len; 579 580 CTASSERT(sizeof(*nip6) + sizeof(*nicmp6) <= MHLEN); 581 n = m_gethdr(M_NOWAIT, n0->m_type); 582 if (n == NULL) { 583 /* Give up remote */ 584 m_freem(n0); 585 break; 586 } 587 588 m_move_pkthdr(n, n0); /* FIB copied. */ 589 n0len = n0->m_pkthdr.len; /* save for use below */ 590 /* 591 * Copy IPv6 and ICMPv6 only. 592 */ 593 nip6 = mtod(n, struct ip6_hdr *); 594 bcopy(ip6, nip6, sizeof(struct ip6_hdr)); 595 nicmp6 = (struct icmp6_hdr *)(nip6 + 1); 596 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr)); 597 noff = sizeof(struct ip6_hdr); 598 /* new mbuf contains only ipv6+icmpv6 headers */ 599 n->m_len = noff + sizeof(struct icmp6_hdr); 600 /* 601 * Adjust mbuf. ip6_plen will be adjusted in 602 * ip6_output(). 603 */ 604 m_adj(n0, off + sizeof(struct icmp6_hdr)); 605 /* recalculate complete packet size */ 606 n->m_pkthdr.len = n0len + (noff - off); 607 n->m_next = n0; 608 } else { 609 nip6 = mtod(n, struct ip6_hdr *); 610 IP6_EXTHDR_GET(nicmp6, struct icmp6_hdr *, n, off, 611 sizeof(*nicmp6)); 612 noff = off; 613 } 614 nicmp6->icmp6_type = ICMP6_ECHO_REPLY; 615 nicmp6->icmp6_code = 0; 616 if (n) { 617 ICMP6STAT_INC(icp6s_reflect); 618 ICMP6STAT_INC(icp6s_outhist[ICMP6_ECHO_REPLY]); 619 icmp6_reflect(n, noff); 620 } 621 break; 622 623 case ICMP6_ECHO_REPLY: 624 icmp6_ifstat_inc(ifp, ifs6_in_echoreply); 625 if (code != 0) 626 goto badcode; 627 break; 628 629 case MLD_LISTENER_QUERY: 630 case MLD_LISTENER_REPORT: 631 case MLD_LISTENER_DONE: 632 case MLDV2_LISTENER_REPORT: 633 /* 634 * Drop MLD traffic which is not link-local, has a hop limit 635 * of greater than 1 hop, or which does not have the 636 * IPv6 HBH Router Alert option. 637 * As IPv6 HBH options are stripped in ip6_input() we must 638 * check an mbuf header flag. 639 * XXX Should we also sanity check that these messages 640 * were directed to a link-local multicast prefix? 641 */ 642 if ((ip6->ip6_hlim != 1) || (m->m_flags & M_RTALERT_MLD) == 0) 643 goto freeit; 644 if (mld_input(m, off, icmp6len) != 0) 645 return (IPPROTO_DONE); 646 /* m stays. */ 647 break; 648 649 case ICMP6_WRUREQUEST: /* ICMP6_FQDN_QUERY */ 650 { 651 enum { WRU, FQDN } mode; 652 653 if (!V_icmp6_nodeinfo) 654 break; 655 656 if (icmp6len == sizeof(struct icmp6_hdr) + 4) 657 mode = WRU; 658 else if (icmp6len >= sizeof(struct icmp6_nodeinfo)) 659 mode = FQDN; 660 else 661 goto badlen; 662 663 if (mode == FQDN) { 664#ifndef PULLDOWN_TEST 665 IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_nodeinfo), 666 IPPROTO_DONE); 667#endif 668 n = m_copy(m, 0, M_COPYALL); 669 if (n) 670 n = ni6_input(n, off); 671 /* XXX meaningless if n == NULL */ 672 noff = sizeof(struct ip6_hdr); 673 } else { 674 struct prison *pr; 675 u_char *p; 676 int maxhlen, hlen; 677 678 /* 679 * XXX: this combination of flags is pointless, 680 * but should we keep this for compatibility? 681 */ 682 if ((V_icmp6_nodeinfo & (ICMP6_NODEINFO_FQDNOK | 683 ICMP6_NODEINFO_TMPADDROK)) != 684 (ICMP6_NODEINFO_FQDNOK | ICMP6_NODEINFO_TMPADDROK)) 685 break; 686 687 if (code != 0) 688 goto badcode; 689 690 CTASSERT(sizeof(*nip6) + sizeof(*nicmp6) + 4 <= MHLEN); 691 n = m_gethdr(M_NOWAIT, m->m_type); 692 if (n == NULL) { 693 /* Give up remote */ 694 break; 695 } 696 if (!m_dup_pkthdr(n, m, M_NOWAIT)) { 697 /* 698 * Previous code did a blind M_COPY_PKTHDR 699 * and said "just for rcvif". If true, then 700 * we could tolerate the dup failing (due to 701 * the deep copy of the tag chain). For now 702 * be conservative and just fail. 703 */ 704 m_free(n); 705 n = NULL; 706 } 707 maxhlen = M_TRAILINGSPACE(n) - 708 (sizeof(*nip6) + sizeof(*nicmp6) + 4); 709 pr = curthread->td_ucred->cr_prison; 710 mtx_lock(&pr->pr_mtx); 711 hlen = strlen(pr->pr_hostname); 712 if (maxhlen > hlen) 713 maxhlen = hlen; 714 /* 715 * Copy IPv6 and ICMPv6 only. 716 */ 717 nip6 = mtod(n, struct ip6_hdr *); 718 bcopy(ip6, nip6, sizeof(struct ip6_hdr)); 719 nicmp6 = (struct icmp6_hdr *)(nip6 + 1); 720 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr)); 721 p = (u_char *)(nicmp6 + 1); 722 bzero(p, 4); 723 /* meaningless TTL */ 724 bcopy(pr->pr_hostname, p + 4, maxhlen); 725 mtx_unlock(&pr->pr_mtx); 726 noff = sizeof(struct ip6_hdr); 727 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) + 728 sizeof(struct icmp6_hdr) + 4 + maxhlen; 729 nicmp6->icmp6_type = ICMP6_WRUREPLY; 730 nicmp6->icmp6_code = 0; 731 } 732 if (n) { 733 ICMP6STAT_INC(icp6s_reflect); 734 ICMP6STAT_INC(icp6s_outhist[ICMP6_WRUREPLY]); 735 icmp6_reflect(n, noff); 736 } 737 break; 738 } 739 740 case ICMP6_WRUREPLY: 741 if (code != 0) 742 goto badcode; 743 break; 744 745 case ND_ROUTER_SOLICIT: 746 icmp6_ifstat_inc(ifp, ifs6_in_routersolicit); 747 if (code != 0) 748 goto badcode; 749 if (icmp6len < sizeof(struct nd_router_solicit)) 750 goto badlen; 751 if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) == NULL) { 752 /* give up local */ 753 754 /* Send incoming SeND packet to user space. */ 755 if (send_sendso_input_hook != NULL) { 756 IP6_EXTHDR_CHECK(m, off, 757 icmp6len, IPPROTO_DONE); 758 error = send_sendso_input_hook(m, ifp, 759 SND_IN, ip6len); 760 /* -1 == no app on SEND socket */ 761 if (error == 0) 762 return (IPPROTO_DONE); 763 nd6_rs_input(m, off, icmp6len); 764 } else 765 nd6_rs_input(m, off, icmp6len); 766 m = NULL; 767 goto freeit; 768 } 769 if (send_sendso_input_hook != NULL) { 770 IP6_EXTHDR_CHECK(n, off, 771 icmp6len, IPPROTO_DONE); 772 error = send_sendso_input_hook(n, ifp, 773 SND_IN, ip6len); 774 if (error == 0) 775 goto freeit; 776 /* -1 == no app on SEND socket */ 777 nd6_rs_input(n, off, icmp6len); 778 } else 779 nd6_rs_input(n, off, icmp6len); 780 /* m stays. */ 781 break; 782 783 case ND_ROUTER_ADVERT: 784 icmp6_ifstat_inc(ifp, ifs6_in_routeradvert); 785 if (code != 0) 786 goto badcode; 787 if (icmp6len < sizeof(struct nd_router_advert)) 788 goto badlen; 789 if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) == NULL) { 790 791 /* Send incoming SeND-protected/ND packet to user space. */ 792 if (send_sendso_input_hook != NULL) { 793 error = send_sendso_input_hook(m, ifp, 794 SND_IN, ip6len); 795 if (error == 0) 796 return (IPPROTO_DONE); 797 nd6_ra_input(m, off, icmp6len); 798 } else 799 nd6_ra_input(m, off, icmp6len); 800 m = NULL; 801 goto freeit; 802 } 803 if (send_sendso_input_hook != NULL) { 804 error = send_sendso_input_hook(n, ifp, 805 SND_IN, ip6len); 806 if (error == 0) 807 goto freeit; 808 nd6_ra_input(n, off, icmp6len); 809 } else 810 nd6_ra_input(n, off, icmp6len); 811 /* m stays. */ 812 break; 813 814 case ND_NEIGHBOR_SOLICIT: 815 icmp6_ifstat_inc(ifp, ifs6_in_neighborsolicit); 816 if (code != 0) 817 goto badcode; 818 if (icmp6len < sizeof(struct nd_neighbor_solicit)) 819 goto badlen; 820 if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) == NULL) { 821 if (send_sendso_input_hook != NULL) { 822 error = send_sendso_input_hook(m, ifp, 823 SND_IN, ip6len); 824 if (error == 0) 825 return (IPPROTO_DONE); 826 nd6_ns_input(m, off, icmp6len); 827 } else 828 nd6_ns_input(m, off, icmp6len); 829 m = NULL; 830 goto freeit; 831 } 832 if (send_sendso_input_hook != NULL) { 833 error = send_sendso_input_hook(n, ifp, 834 SND_IN, ip6len); 835 if (error == 0) 836 goto freeit; 837 nd6_ns_input(n, off, icmp6len); 838 } else 839 nd6_ns_input(n, off, icmp6len); 840 /* m stays. */ 841 break; 842 843 case ND_NEIGHBOR_ADVERT: 844 icmp6_ifstat_inc(ifp, ifs6_in_neighboradvert); 845 if (code != 0) 846 goto badcode; 847 if (icmp6len < sizeof(struct nd_neighbor_advert)) 848 goto badlen; 849 if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) == NULL) { 850 851 /* Send incoming SeND-protected/ND packet to user space. */ 852 if (send_sendso_input_hook != NULL) { 853 error = send_sendso_input_hook(m, ifp, 854 SND_IN, ip6len); 855 if (error == 0) 856 return (IPPROTO_DONE); 857 nd6_na_input(m, off, icmp6len); 858 } else 859 nd6_na_input(m, off, icmp6len); 860 m = NULL; 861 goto freeit; 862 } 863 if (send_sendso_input_hook != NULL) { 864 error = send_sendso_input_hook(n, ifp, 865 SND_IN, ip6len); 866 if (error == 0) 867 goto freeit; 868 nd6_na_input(n, off, icmp6len); 869 } else 870 nd6_na_input(n, off, icmp6len); 871 /* m stays. */ 872 break; 873 874 case ND_REDIRECT: 875 icmp6_ifstat_inc(ifp, ifs6_in_redirect); 876 if (code != 0) 877 goto badcode; 878 if (icmp6len < sizeof(struct nd_redirect)) 879 goto badlen; 880 if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) == NULL) { 881 if (send_sendso_input_hook != NULL) { 882 error = send_sendso_input_hook(m, ifp, 883 SND_IN, ip6len); 884 if (error == 0) 885 return (IPPROTO_DONE); 886 icmp6_redirect_input(m, off); 887 } else 888 icmp6_redirect_input(m, off); 889 m = NULL; 890 goto freeit; 891 } 892 if (send_sendso_input_hook != NULL) { 893 error = send_sendso_input_hook(n, ifp, 894 SND_IN, ip6len); 895 if (error == 0) 896 goto freeit; 897 icmp6_redirect_input(n, off); 898 } else 899 icmp6_redirect_input(n, off); 900 /* m stays. */ 901 break; 902 903 case ICMP6_ROUTER_RENUMBERING: 904 if (code != ICMP6_ROUTER_RENUMBERING_COMMAND && 905 code != ICMP6_ROUTER_RENUMBERING_RESULT) 906 goto badcode; 907 if (icmp6len < sizeof(struct icmp6_router_renum)) 908 goto badlen; 909 break; 910 911 default: 912 nd6log((LOG_DEBUG, 913 "icmp6_input: unknown type %d(src=%s, dst=%s, ifid=%d)\n", 914 icmp6->icmp6_type, ip6_sprintf(ip6bufs, &ip6->ip6_src), 915 ip6_sprintf(ip6bufd, &ip6->ip6_dst), 916 ifp ? ifp->if_index : 0)); 917 if (icmp6->icmp6_type < ICMP6_ECHO_REQUEST) { 918 /* ICMPv6 error: MUST deliver it by spec... */ 919 code = PRC_NCMDS; 920 /* deliver */ 921 } else { 922 /* ICMPv6 informational: MUST not deliver */ 923 break; 924 } 925 deliver: 926 if (icmp6_notify_error(&m, off, icmp6len, code) != 0) { 927 /* In this case, m should've been freed. */ 928 return (IPPROTO_DONE); 929 } 930 break; 931 932 badcode: 933 ICMP6STAT_INC(icp6s_badcode); 934 break; 935 936 badlen: 937 ICMP6STAT_INC(icp6s_badlen); 938 break; 939 } 940 941 /* deliver the packet to appropriate sockets */ 942 icmp6_rip6_input(&m, *offp); 943 944 return IPPROTO_DONE; 945 946 freeit: 947 m_freem(m); 948 return IPPROTO_DONE; 949} 950 951static int 952icmp6_notify_error(struct mbuf **mp, int off, int icmp6len, int code) 953{ 954 struct mbuf *m = *mp; 955 struct icmp6_hdr *icmp6; 956 struct ip6_hdr *eip6; 957 u_int32_t notifymtu; 958 struct sockaddr_in6 icmp6src, icmp6dst; 959 960 if (icmp6len < sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr)) { 961 ICMP6STAT_INC(icp6s_tooshort); 962 goto freeit; 963 } 964#ifndef PULLDOWN_TEST 965 IP6_EXTHDR_CHECK(m, off, 966 sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr), -1); 967 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 968#else 969 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, 970 sizeof(*icmp6) + sizeof(struct ip6_hdr)); 971 if (icmp6 == NULL) { 972 ICMP6STAT_INC(icp6s_tooshort); 973 return (-1); 974 } 975#endif 976 eip6 = (struct ip6_hdr *)(icmp6 + 1); 977 978 /* Detect the upper level protocol */ 979 { 980 void (*ctlfunc)(int, struct sockaddr *, void *); 981 u_int8_t nxt = eip6->ip6_nxt; 982 int eoff = off + sizeof(struct icmp6_hdr) + 983 sizeof(struct ip6_hdr); 984 struct ip6ctlparam ip6cp; 985 struct in6_addr *finaldst = NULL; 986 int icmp6type = icmp6->icmp6_type; 987 struct ip6_frag *fh; 988 struct ip6_rthdr *rth; 989 struct ip6_rthdr0 *rth0; 990 int rthlen; 991 992 while (1) { /* XXX: should avoid infinite loop explicitly? */ 993 struct ip6_ext *eh; 994 995 switch (nxt) { 996 case IPPROTO_HOPOPTS: 997 case IPPROTO_DSTOPTS: 998 case IPPROTO_AH: 999#ifndef PULLDOWN_TEST 1000 IP6_EXTHDR_CHECK(m, 0, 1001 eoff + sizeof(struct ip6_ext), -1); 1002 eh = (struct ip6_ext *)(mtod(m, caddr_t) + eoff); 1003#else 1004 IP6_EXTHDR_GET(eh, struct ip6_ext *, m, 1005 eoff, sizeof(*eh)); 1006 if (eh == NULL) { 1007 ICMP6STAT_INC(icp6s_tooshort); 1008 return (-1); 1009 } 1010#endif 1011 1012 if (nxt == IPPROTO_AH) 1013 eoff += (eh->ip6e_len + 2) << 2; 1014 else 1015 eoff += (eh->ip6e_len + 1) << 3; 1016 nxt = eh->ip6e_nxt; 1017 break; 1018 case IPPROTO_ROUTING: 1019 /* 1020 * When the erroneous packet contains a 1021 * routing header, we should examine the 1022 * header to determine the final destination. 1023 * Otherwise, we can't properly update 1024 * information that depends on the final 1025 * destination (e.g. path MTU). 1026 */ 1027#ifndef PULLDOWN_TEST 1028 IP6_EXTHDR_CHECK(m, 0, eoff + sizeof(*rth), -1); 1029 rth = (struct ip6_rthdr *) 1030 (mtod(m, caddr_t) + eoff); 1031#else 1032 IP6_EXTHDR_GET(rth, struct ip6_rthdr *, m, 1033 eoff, sizeof(*rth)); 1034 if (rth == NULL) { 1035 ICMP6STAT_INC(icp6s_tooshort); 1036 return (-1); 1037 } 1038#endif 1039 rthlen = (rth->ip6r_len + 1) << 3; 1040 /* 1041 * XXX: currently there is no 1042 * officially defined type other 1043 * than type-0. 1044 * Note that if the segment left field 1045 * is 0, all intermediate hops must 1046 * have been passed. 1047 */ 1048 if (rth->ip6r_segleft && 1049 rth->ip6r_type == IPV6_RTHDR_TYPE_0) { 1050 int hops; 1051 1052#ifndef PULLDOWN_TEST 1053 IP6_EXTHDR_CHECK(m, 0, eoff + rthlen, -1); 1054 rth0 = (struct ip6_rthdr0 *) 1055 (mtod(m, caddr_t) + eoff); 1056#else 1057 IP6_EXTHDR_GET(rth0, 1058 struct ip6_rthdr0 *, m, 1059 eoff, rthlen); 1060 if (rth0 == NULL) { 1061 ICMP6STAT_INC(icp6s_tooshort); 1062 return (-1); 1063 } 1064#endif 1065 /* just ignore a bogus header */ 1066 if ((rth0->ip6r0_len % 2) == 0 && 1067 (hops = rth0->ip6r0_len/2)) 1068 finaldst = (struct in6_addr *)(rth0 + 1) + (hops - 1); 1069 } 1070 eoff += rthlen; 1071 nxt = rth->ip6r_nxt; 1072 break; 1073 case IPPROTO_FRAGMENT: 1074#ifndef PULLDOWN_TEST 1075 IP6_EXTHDR_CHECK(m, 0, eoff + 1076 sizeof(struct ip6_frag), -1); 1077 fh = (struct ip6_frag *)(mtod(m, caddr_t) + 1078 eoff); 1079#else 1080 IP6_EXTHDR_GET(fh, struct ip6_frag *, m, 1081 eoff, sizeof(*fh)); 1082 if (fh == NULL) { 1083 ICMP6STAT_INC(icp6s_tooshort); 1084 return (-1); 1085 } 1086#endif 1087 /* 1088 * Data after a fragment header is meaningless 1089 * unless it is the first fragment, but 1090 * we'll go to the notify label for path MTU 1091 * discovery. 1092 */ 1093 if (fh->ip6f_offlg & IP6F_OFF_MASK) 1094 goto notify; 1095 1096 eoff += sizeof(struct ip6_frag); 1097 nxt = fh->ip6f_nxt; 1098 break; 1099 default: 1100 /* 1101 * This case includes ESP and the No Next 1102 * Header. In such cases going to the notify 1103 * label does not have any meaning 1104 * (i.e. ctlfunc will be NULL), but we go 1105 * anyway since we might have to update 1106 * path MTU information. 1107 */ 1108 goto notify; 1109 } 1110 } 1111 notify: 1112#ifndef PULLDOWN_TEST 1113 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 1114#else 1115 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, 1116 sizeof(*icmp6) + sizeof(struct ip6_hdr)); 1117 if (icmp6 == NULL) { 1118 ICMP6STAT_INC(icp6s_tooshort); 1119 return (-1); 1120 } 1121#endif 1122 1123 /* 1124 * retrieve parameters from the inner IPv6 header, and convert 1125 * them into sockaddr structures. 1126 * XXX: there is no guarantee that the source or destination 1127 * addresses of the inner packet are in the same scope as 1128 * the addresses of the icmp packet. But there is no other 1129 * way to determine the zone. 1130 */ 1131 eip6 = (struct ip6_hdr *)(icmp6 + 1); 1132 1133 bzero(&icmp6dst, sizeof(icmp6dst)); 1134 icmp6dst.sin6_len = sizeof(struct sockaddr_in6); 1135 icmp6dst.sin6_family = AF_INET6; 1136 if (finaldst == NULL) 1137 icmp6dst.sin6_addr = eip6->ip6_dst; 1138 else 1139 icmp6dst.sin6_addr = *finaldst; 1140 if (in6_setscope(&icmp6dst.sin6_addr, m->m_pkthdr.rcvif, NULL)) 1141 goto freeit; 1142 bzero(&icmp6src, sizeof(icmp6src)); 1143 icmp6src.sin6_len = sizeof(struct sockaddr_in6); 1144 icmp6src.sin6_family = AF_INET6; 1145 icmp6src.sin6_addr = eip6->ip6_src; 1146 if (in6_setscope(&icmp6src.sin6_addr, m->m_pkthdr.rcvif, NULL)) 1147 goto freeit; 1148 icmp6src.sin6_flowinfo = 1149 (eip6->ip6_flow & IPV6_FLOWLABEL_MASK); 1150 1151 if (finaldst == NULL) 1152 finaldst = &eip6->ip6_dst; 1153 ip6cp.ip6c_m = m; 1154 ip6cp.ip6c_icmp6 = icmp6; 1155 ip6cp.ip6c_ip6 = (struct ip6_hdr *)(icmp6 + 1); 1156 ip6cp.ip6c_off = eoff; 1157 ip6cp.ip6c_finaldst = finaldst; 1158 ip6cp.ip6c_src = &icmp6src; 1159 ip6cp.ip6c_nxt = nxt; 1160 1161 if (icmp6type == ICMP6_PACKET_TOO_BIG) { 1162 notifymtu = ntohl(icmp6->icmp6_mtu); 1163 ip6cp.ip6c_cmdarg = (void *)¬ifymtu; 1164 icmp6_mtudisc_update(&ip6cp, 1); /*XXX*/ 1165 } 1166 1167 ctlfunc = (void (*)(int, struct sockaddr *, void *)) 1168 (inet6sw[ip6_protox[nxt]].pr_ctlinput); 1169 if (ctlfunc) { 1170 (void) (*ctlfunc)(code, (struct sockaddr *)&icmp6dst, 1171 &ip6cp); 1172 } 1173 } 1174 *mp = m; 1175 return (0); 1176 1177 freeit: 1178 m_freem(m); 1179 return (-1); 1180} 1181 1182void 1183icmp6_mtudisc_update(struct ip6ctlparam *ip6cp, int validated) 1184{ 1185 struct in6_addr *dst = ip6cp->ip6c_finaldst; 1186 struct icmp6_hdr *icmp6 = ip6cp->ip6c_icmp6; 1187 struct mbuf *m = ip6cp->ip6c_m; /* will be necessary for scope issue */ 1188 u_int mtu = ntohl(icmp6->icmp6_mtu); 1189 struct in_conninfo inc; 1190 1191#if 0 1192 /* 1193 * RFC2460 section 5, last paragraph. 1194 * even though minimum link MTU for IPv6 is IPV6_MMTU, 1195 * we may see ICMPv6 too big with mtu < IPV6_MMTU 1196 * due to packet translator in the middle. 1197 * see ip6_output() and ip6_getpmtu() "alwaysfrag" case for 1198 * special handling. 1199 */ 1200 if (mtu < IPV6_MMTU) 1201 return; 1202#endif 1203 1204 /* 1205 * we reject ICMPv6 too big with abnormally small value. 1206 * XXX what is the good definition of "abnormally small"? 1207 */ 1208 if (mtu < sizeof(struct ip6_hdr) + sizeof(struct ip6_frag) + 8) 1209 return; 1210 1211 if (!validated) 1212 return; 1213 1214 /* 1215 * In case the suggested mtu is less than IPV6_MMTU, we 1216 * only need to remember that it was for above mentioned 1217 * "alwaysfrag" case. 1218 * Try to be as close to the spec as possible. 1219 */ 1220 if (mtu < IPV6_MMTU) 1221 mtu = IPV6_MMTU - 8; 1222 1223 bzero(&inc, sizeof(inc)); 1224 inc.inc_fibnum = M_GETFIB(m); 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 */ 1247static struct mbuf * 1248ni6_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 */ 1577static struct mbuf * 1578ni6_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 */ 1671static int 1672ni6_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 */ 1731static int 1732ni6_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 1824static int 1825ni6_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_uptime) 1930 ltime = htonl(ifa6->ia6_lifetime.ia6t_expire - time_uptime); 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 */ 1967static int 1968icmp6_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 */ 2127void 2128icmp6_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 2290void 2291icmp6_fasttimo(void) 2292{ 2293 2294 mld_fasttimo(); 2295} 2296 2297void 2298icmp6_slowtimo(void) 2299{ 2300 2301 mld_slowtimo(); 2302} 2303 2304static const char * 2305icmp6_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 2318void 2319icmp6_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 } 2503 2504 freeit: 2505 m_freem(m); 2506 return; 2507 2508 bad: 2509 ICMP6STAT_INC(icp6s_badredirect); 2510 m_freem(m); 2511} 2512 2513void 2514icmp6_redirect_output(struct mbuf *m0, struct rtentry *rt) 2515{ 2516 struct ifnet *ifp; /* my outgoing interface */ 2517 struct in6_addr *ifp_ll6; 2518 struct in6_addr *router_ll6; 2519 struct ip6_hdr *sip6; /* m0 as struct ip6_hdr */ 2520 struct mbuf *m = NULL; /* newly allocated one */ 2521 struct m_tag *mtag; 2522 struct ip6_hdr *ip6; /* m as struct ip6_hdr */ 2523 struct nd_redirect *nd_rd; 2524 struct llentry *ln = NULL; 2525 size_t maxlen; 2526 u_char *p; 2527 struct ifnet *outif = NULL; 2528 struct sockaddr_in6 src_sa; 2529 2530 icmp6_errcount(ND_REDIRECT, 0); 2531 2532 /* if we are not router, we don't send icmp6 redirect */ 2533 if (!V_ip6_forwarding) 2534 goto fail; 2535 2536 /* sanity check */ 2537 if (!m0 || !rt || !(rt->rt_flags & RTF_UP) || !(ifp = rt->rt_ifp)) 2538 goto fail; 2539 2540 /* 2541 * Address check: 2542 * the source address must identify a neighbor, and 2543 * the destination address must not be a multicast address 2544 * [RFC 2461, sec 8.2] 2545 */ 2546 sip6 = mtod(m0, struct ip6_hdr *); 2547 bzero(&src_sa, sizeof(src_sa)); 2548 src_sa.sin6_family = AF_INET6; 2549 src_sa.sin6_len = sizeof(src_sa); 2550 src_sa.sin6_addr = sip6->ip6_src; 2551 if (nd6_is_addr_neighbor(&src_sa, ifp) == 0) 2552 goto fail; 2553 if (IN6_IS_ADDR_MULTICAST(&sip6->ip6_dst)) 2554 goto fail; /* what should we do here? */ 2555 2556 /* rate limit */ 2557 if (icmp6_ratelimit(&sip6->ip6_src, ND_REDIRECT, 0)) 2558 goto fail; 2559 2560 /* 2561 * Since we are going to append up to 1280 bytes (= IPV6_MMTU), 2562 * we almost always ask for an mbuf cluster for simplicity. 2563 * (MHLEN < IPV6_MMTU is almost always true) 2564 */ 2565#if IPV6_MMTU >= MCLBYTES 2566# error assumption failed about IPV6_MMTU and MCLBYTES 2567#endif 2568 m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR); 2569 if (m == NULL) 2570 goto fail; 2571 M_SETFIB(m, rt->rt_fibnum); 2572 maxlen = M_TRAILINGSPACE(m); 2573 maxlen = min(IPV6_MMTU, maxlen); 2574 /* just for safety */ 2575 if (maxlen < sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) + 2576 ((sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7)) { 2577 goto fail; 2578 } 2579 2580 { 2581 /* get ip6 linklocal address for ifp(my outgoing interface). */ 2582 struct in6_ifaddr *ia; 2583 if ((ia = in6ifa_ifpforlinklocal(ifp, 2584 IN6_IFF_NOTREADY| 2585 IN6_IFF_ANYCAST)) == NULL) 2586 goto fail; 2587 ifp_ll6 = &ia->ia_addr.sin6_addr; 2588 /* XXXRW: reference released prematurely. */ 2589 ifa_free(&ia->ia_ifa); 2590 } 2591 2592 /* get ip6 linklocal address for the router. */ 2593 if (rt->rt_gateway && (rt->rt_flags & RTF_GATEWAY)) { 2594 struct sockaddr_in6 *sin6; 2595 sin6 = (struct sockaddr_in6 *)rt->rt_gateway; 2596 router_ll6 = &sin6->sin6_addr; 2597 if (!IN6_IS_ADDR_LINKLOCAL(router_ll6)) 2598 router_ll6 = (struct in6_addr *)NULL; 2599 } else 2600 router_ll6 = (struct in6_addr *)NULL; 2601 2602 /* ip6 */ 2603 ip6 = mtod(m, struct ip6_hdr *); 2604 ip6->ip6_flow = 0; 2605 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2606 ip6->ip6_vfc |= IPV6_VERSION; 2607 /* ip6->ip6_plen will be set later */ 2608 ip6->ip6_nxt = IPPROTO_ICMPV6; 2609 ip6->ip6_hlim = 255; 2610 /* ip6->ip6_src must be linklocal addr for my outgoing if. */ 2611 bcopy(ifp_ll6, &ip6->ip6_src, sizeof(struct in6_addr)); 2612 bcopy(&sip6->ip6_src, &ip6->ip6_dst, sizeof(struct in6_addr)); 2613 2614 /* ND Redirect */ 2615 nd_rd = (struct nd_redirect *)(ip6 + 1); 2616 nd_rd->nd_rd_type = ND_REDIRECT; 2617 nd_rd->nd_rd_code = 0; 2618 nd_rd->nd_rd_reserved = 0; 2619 if (rt->rt_flags & RTF_GATEWAY) { 2620 /* 2621 * nd_rd->nd_rd_target must be a link-local address in 2622 * better router cases. 2623 */ 2624 if (!router_ll6) 2625 goto fail; 2626 bcopy(router_ll6, &nd_rd->nd_rd_target, 2627 sizeof(nd_rd->nd_rd_target)); 2628 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2629 sizeof(nd_rd->nd_rd_dst)); 2630 } else { 2631 /* make sure redtgt == reddst */ 2632 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_target, 2633 sizeof(nd_rd->nd_rd_target)); 2634 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2635 sizeof(nd_rd->nd_rd_dst)); 2636 } 2637 2638 p = (u_char *)(nd_rd + 1); 2639 2640 if (!router_ll6) 2641 goto nolladdropt; 2642 2643 { 2644 /* target lladdr option */ 2645 int len; 2646 struct nd_opt_hdr *nd_opt; 2647 char *lladdr; 2648 2649 IF_AFDATA_RLOCK(ifp); 2650 ln = nd6_lookup(router_ll6, 0, ifp); 2651 IF_AFDATA_RUNLOCK(ifp); 2652 if (ln == NULL) 2653 goto nolladdropt; 2654 2655 len = sizeof(*nd_opt) + ifp->if_addrlen; 2656 len = (len + 7) & ~7; /* round by 8 */ 2657 /* safety check */ 2658 if (len + (p - (u_char *)ip6) > maxlen) 2659 goto nolladdropt; 2660 2661 if (ln->la_flags & LLE_VALID) { 2662 nd_opt = (struct nd_opt_hdr *)p; 2663 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 2664 nd_opt->nd_opt_len = len >> 3; 2665 lladdr = (char *)(nd_opt + 1); 2666 bcopy(&ln->ll_addr, lladdr, ifp->if_addrlen); 2667 p += len; 2668 } 2669 } 2670nolladdropt: 2671 if (ln != NULL) 2672 LLE_RUNLOCK(ln); 2673 2674 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2675 2676 /* just to be safe */ 2677#ifdef M_DECRYPTED /*not openbsd*/ 2678 if (m0->m_flags & M_DECRYPTED) 2679 goto noredhdropt; 2680#endif 2681 if (p - (u_char *)ip6 > maxlen) 2682 goto noredhdropt; 2683 2684 { 2685 /* redirected header option */ 2686 int len; 2687 struct nd_opt_rd_hdr *nd_opt_rh; 2688 2689 /* 2690 * compute the maximum size for icmp6 redirect header option. 2691 * XXX room for auth header? 2692 */ 2693 len = maxlen - (p - (u_char *)ip6); 2694 len &= ~7; 2695 2696 /* This is just for simplicity. */ 2697 if (m0->m_pkthdr.len != m0->m_len) { 2698 if (m0->m_next) { 2699 m_freem(m0->m_next); 2700 m0->m_next = NULL; 2701 } 2702 m0->m_pkthdr.len = m0->m_len; 2703 } 2704 2705 /* 2706 * Redirected header option spec (RFC2461 4.6.3) talks nothing 2707 * about padding/truncate rule for the original IP packet. 2708 * From the discussion on IPv6imp in Feb 1999, 2709 * the consensus was: 2710 * - "attach as much as possible" is the goal 2711 * - pad if not aligned (original size can be guessed by 2712 * original ip6 header) 2713 * Following code adds the padding if it is simple enough, 2714 * and truncates if not. 2715 */ 2716 if (m0->m_next || m0->m_pkthdr.len != m0->m_len) 2717 panic("assumption failed in %s:%d", __FILE__, 2718 __LINE__); 2719 2720 if (len - sizeof(*nd_opt_rh) < m0->m_pkthdr.len) { 2721 /* not enough room, truncate */ 2722 m0->m_pkthdr.len = m0->m_len = len - 2723 sizeof(*nd_opt_rh); 2724 } else { 2725 /* enough room, pad or truncate */ 2726 size_t extra; 2727 2728 extra = m0->m_pkthdr.len % 8; 2729 if (extra) { 2730 /* pad if easy enough, truncate if not */ 2731 if (8 - extra <= M_TRAILINGSPACE(m0)) { 2732 /* pad */ 2733 m0->m_len += (8 - extra); 2734 m0->m_pkthdr.len += (8 - extra); 2735 } else { 2736 /* truncate */ 2737 m0->m_pkthdr.len -= extra; 2738 m0->m_len -= extra; 2739 } 2740 } 2741 len = m0->m_pkthdr.len + sizeof(*nd_opt_rh); 2742 m0->m_pkthdr.len = m0->m_len = len - 2743 sizeof(*nd_opt_rh); 2744 } 2745 2746 nd_opt_rh = (struct nd_opt_rd_hdr *)p; 2747 bzero(nd_opt_rh, sizeof(*nd_opt_rh)); 2748 nd_opt_rh->nd_opt_rh_type = ND_OPT_REDIRECTED_HEADER; 2749 nd_opt_rh->nd_opt_rh_len = len >> 3; 2750 p += sizeof(*nd_opt_rh); 2751 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2752 2753 /* connect m0 to m */ 2754 m_tag_delete_chain(m0, NULL); 2755 m0->m_flags &= ~M_PKTHDR; 2756 m->m_next = m0; 2757 m->m_pkthdr.len = m->m_len + m0->m_len; 2758 m0 = NULL; 2759 } 2760noredhdropt:; 2761 if (m0) { 2762 m_freem(m0); 2763 m0 = NULL; 2764 } 2765 2766 /* XXX: clear embedded link IDs in the inner header */ 2767 in6_clearscope(&sip6->ip6_src); 2768 in6_clearscope(&sip6->ip6_dst); 2769 in6_clearscope(&nd_rd->nd_rd_target); 2770 in6_clearscope(&nd_rd->nd_rd_dst); 2771 2772 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr)); 2773 2774 nd_rd->nd_rd_cksum = 0; 2775 nd_rd->nd_rd_cksum = in6_cksum(m, IPPROTO_ICMPV6, 2776 sizeof(*ip6), ntohs(ip6->ip6_plen)); 2777 2778 if (send_sendso_input_hook != NULL) { 2779 mtag = m_tag_get(PACKET_TAG_ND_OUTGOING, sizeof(unsigned short), 2780 M_NOWAIT); 2781 if (mtag == NULL) 2782 goto fail; 2783 *(unsigned short *)(mtag + 1) = nd_rd->nd_rd_type; 2784 m_tag_prepend(m, mtag); 2785 } 2786 2787 /* send the packet to outside... */ 2788 ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL); 2789 if (outif) { 2790 icmp6_ifstat_inc(outif, ifs6_out_msg); 2791 icmp6_ifstat_inc(outif, ifs6_out_redirect); 2792 } 2793 ICMP6STAT_INC(icp6s_outhist[ND_REDIRECT]); 2794 2795 return; 2796 2797fail: 2798 if (m) 2799 m_freem(m); 2800 if (m0) 2801 m_freem(m0); 2802} 2803 2804/* 2805 * ICMPv6 socket option processing. 2806 */ 2807int 2808icmp6_ctloutput(struct socket *so, struct sockopt *sopt) 2809{ 2810 int error = 0; 2811 int optlen; 2812 struct inpcb *inp = sotoinpcb(so); 2813 int level, op, optname; 2814 2815 if (sopt) { 2816 level = sopt->sopt_level; 2817 op = sopt->sopt_dir; 2818 optname = sopt->sopt_name; 2819 optlen = sopt->sopt_valsize; 2820 } else 2821 level = op = optname = optlen = 0; 2822 2823 if (level != IPPROTO_ICMPV6) { 2824 return EINVAL; 2825 } 2826 2827 switch (op) { 2828 case PRCO_SETOPT: 2829 switch (optname) { 2830 case ICMP6_FILTER: 2831 { 2832 struct icmp6_filter ic6f; 2833 2834 if (optlen != sizeof(ic6f)) { 2835 error = EMSGSIZE; 2836 break; 2837 } 2838 error = sooptcopyin(sopt, &ic6f, optlen, optlen); 2839 if (error == 0) { 2840 INP_WLOCK(inp); 2841 *inp->in6p_icmp6filt = ic6f; 2842 INP_WUNLOCK(inp); 2843 } 2844 break; 2845 } 2846 2847 default: 2848 error = ENOPROTOOPT; 2849 break; 2850 } 2851 break; 2852 2853 case PRCO_GETOPT: 2854 switch (optname) { 2855 case ICMP6_FILTER: 2856 { 2857 struct icmp6_filter ic6f; 2858 2859 INP_RLOCK(inp); 2860 ic6f = *inp->in6p_icmp6filt; 2861 INP_RUNLOCK(inp); 2862 error = sooptcopyout(sopt, &ic6f, sizeof(ic6f)); 2863 break; 2864 } 2865 2866 default: 2867 error = ENOPROTOOPT; 2868 break; 2869 } 2870 break; 2871 } 2872 2873 return (error); 2874} 2875 2876/* 2877 * Perform rate limit check. 2878 * Returns 0 if it is okay to send the icmp6 packet. 2879 * Returns 1 if the router SHOULD NOT send this icmp6 packet due to rate 2880 * limitation. 2881 * 2882 * XXX per-destination/type check necessary? 2883 * 2884 * dst - not used at this moment 2885 * type - not used at this moment 2886 * code - not used at this moment 2887 */ 2888static int 2889icmp6_ratelimit(const struct in6_addr *dst, const int type, 2890 const int code) 2891{ 2892 int ret; 2893 2894 ret = 0; /* okay to send */ 2895 2896 /* PPS limit */ 2897 if (!ppsratecheck(&V_icmp6errppslim_last, &V_icmp6errpps_count, 2898 V_icmp6errppslim)) { 2899 /* The packet is subject to rate limit */ 2900 ret++; 2901 } 2902 2903 return ret; 2904} 2905