1 /* $FreeBSD: src/sys/netinet6/icmp6.c,v 1.6.2.13 2003/05/06 06:46:58 suz Exp $ */ 2 /* $DragonFly: src/sys/netinet6/icmp6.c,v 1.16 2005/01/06 17:59:32 hsu Exp $ */ 3 /* $KAME: icmp6.c,v 1.211 2001/04/04 05:56:20 itojun Exp $ */ 4 5 /* 6 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 7 * All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. Neither the name of the project nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 /* 35 * Copyright (c) 1982, 1986, 1988, 1993 36 * The Regents of the University of California. All rights reserved. 37 * 38 * Redistribution and use in source and binary forms, with or without 39 * modification, are permitted provided that the following conditions 40 * are met: 41 * 1. Redistributions of source code must retain the above copyright 42 * notice, this list of conditions and the following disclaimer. 43 * 2. Redistributions in binary form must reproduce the above copyright 44 * notice, this list of conditions and the following disclaimer in the 45 * documentation and/or other materials provided with the distribution. 46 * 3. All advertising materials mentioning features or use of this software 47 * must display the following acknowledgement: 48 * This product includes software developed by the University of 49 * California, Berkeley and its contributors. 50 * 4. Neither the name of the University nor the names of its contributors 51 * may be used to endorse or promote products derived from this software 52 * without specific prior written permission. 53 * 54 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 55 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 56 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 57 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 58 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 59 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 60 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 61 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 62 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 63 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 64 * SUCH DAMAGE. 65 * 66 * @(#)ip_icmp.c 8.2 (Berkeley) 1/4/94 67 */ 68 69 #include "opt_inet.h" 70 #include "opt_inet6.h" 71 #include "opt_ipsec.h" 72 73 #include <sys/param.h> 74 #include <sys/systm.h> 75 #include <sys/malloc.h> 76 #include <sys/mbuf.h> 77 #include <sys/protosw.h> 78 #include <sys/socket.h> 79 #include <sys/socketvar.h> 80 #include <sys/time.h> 81 #include <sys/kernel.h> 82 #include <sys/syslog.h> 83 #include <sys/domain.h> 84 85 #include <net/if.h> 86 #include <net/route.h> 87 #include <net/if_dl.h> 88 #include <net/if_types.h> 89 90 #include <netinet/in.h> 91 #include <netinet/in_var.h> 92 #include <netinet/ip6.h> 93 #include <netinet6/ip6_var.h> 94 #include <netinet/icmp6.h> 95 #include <netinet6/mld6_var.h> 96 #include <netinet/in_pcb.h> 97 #include <netinet6/in6_pcb.h> 98 #include <netinet6/nd6.h> 99 #include <netinet6/in6_ifattach.h> 100 #include <netinet6/ip6protosw.h> 101 102 #ifdef IPSEC 103 #include <netinet6/ipsec.h> 104 #include <netproto/key/key.h> 105 #endif 106 107 #ifdef FAST_IPSEC 108 #include <netproto/ipsec/ipsec.h> 109 #include <netproto/ipsec/key.h> 110 #define IPSEC 111 #endif 112 113 #include <net/net_osdep.h> 114 115 #ifdef HAVE_NRL_INPCB 116 /* inpcb members */ 117 #define in6pcb inpcb 118 #define in6p_laddr inp_laddr6 119 #define in6p_faddr inp_faddr6 120 #define in6p_icmp6filt inp_icmp6filt 121 #define in6p_route inp_route 122 #define in6p_socket inp_socket 123 #define in6p_flags inp_flags 124 #define in6p_moptions inp_moptions6 125 #define in6p_outputopts inp_outputopts6 126 #define in6p_ip6 inp_ipv6 127 #define in6p_flowinfo inp_flowinfo 128 #define in6p_sp inp_sp 129 #define in6p_next inp_next 130 #define in6p_prev inp_prev 131 /* macro names */ 132 #define sotoin6pcb sotoinpcb 133 /* function names */ 134 #define in6_pcbdetach in_pcbdetach 135 #define in6_rtchange in_rtchange 136 137 /* 138 * for KAME src sync over BSD*'s. XXX: FreeBSD (>=3) are VERY different from 139 * others... 140 */ 141 #define in6p_ip6_nxt inp_ipv6.ip6_nxt 142 #endif 143 144 /* 145 * ppratecheck() is available, so define it here. 146 */ 147 #define HAVE_PPSRATECHECK 148 149 extern struct domain inet6domain; 150 extern struct ip6protosw inet6sw[]; 151 extern u_char ip6_protox[]; 152 153 struct icmp6stat icmp6stat; 154 155 extern struct inpcbinfo ripcbinfo; 156 extern int icmp6errppslim; 157 static int icmp6errpps_count = 0; 158 static struct timeval icmp6errppslim_last; 159 extern int icmp6_nodeinfo; 160 161 static void icmp6_errcount (struct icmp6errstat *, int, int); 162 static int icmp6_rip6_input (struct mbuf **, int); 163 static int icmp6_ratelimit (const struct in6_addr *, const int, const int); 164 static const char *icmp6_redirect_diag (struct in6_addr *, 165 struct in6_addr *, struct in6_addr *); 166 #ifndef HAVE_PPSRATECHECK 167 static int ppsratecheck (struct timeval *, int *, int); 168 #endif 169 static struct mbuf *ni6_input (struct mbuf *, int); 170 static struct mbuf *ni6_nametodns (const char *, int, int); 171 static int ni6_dnsmatch (const char *, int, const char *, int); 172 static int ni6_addrs (struct icmp6_nodeinfo *, struct mbuf *, 173 struct ifnet **, char *); 174 static int ni6_store_addrs (struct icmp6_nodeinfo *, struct icmp6_nodeinfo *, 175 struct ifnet *, int); 176 static int icmp6_notify_error (struct mbuf *, int, int, int); 177 178 #ifdef COMPAT_RFC1885 179 static struct route_in6 icmp6_reflect_rt; 180 #endif 181 182 183 void 184 icmp6_init(void) 185 { 186 mld6_init(); 187 } 188 189 static void 190 icmp6_errcount(struct icmp6errstat *stat, int type, int code) 191 { 192 switch (type) { 193 case ICMP6_DST_UNREACH: 194 switch (code) { 195 case ICMP6_DST_UNREACH_NOROUTE: 196 stat->icp6errs_dst_unreach_noroute++; 197 return; 198 case ICMP6_DST_UNREACH_ADMIN: 199 stat->icp6errs_dst_unreach_admin++; 200 return; 201 case ICMP6_DST_UNREACH_BEYONDSCOPE: 202 stat->icp6errs_dst_unreach_beyondscope++; 203 return; 204 case ICMP6_DST_UNREACH_ADDR: 205 stat->icp6errs_dst_unreach_addr++; 206 return; 207 case ICMP6_DST_UNREACH_NOPORT: 208 stat->icp6errs_dst_unreach_noport++; 209 return; 210 } 211 break; 212 case ICMP6_PACKET_TOO_BIG: 213 stat->icp6errs_packet_too_big++; 214 return; 215 case ICMP6_TIME_EXCEEDED: 216 switch (code) { 217 case ICMP6_TIME_EXCEED_TRANSIT: 218 stat->icp6errs_time_exceed_transit++; 219 return; 220 case ICMP6_TIME_EXCEED_REASSEMBLY: 221 stat->icp6errs_time_exceed_reassembly++; 222 return; 223 } 224 break; 225 case ICMP6_PARAM_PROB: 226 switch (code) { 227 case ICMP6_PARAMPROB_HEADER: 228 stat->icp6errs_paramprob_header++; 229 return; 230 case ICMP6_PARAMPROB_NEXTHEADER: 231 stat->icp6errs_paramprob_nextheader++; 232 return; 233 case ICMP6_PARAMPROB_OPTION: 234 stat->icp6errs_paramprob_option++; 235 return; 236 } 237 break; 238 case ND_REDIRECT: 239 stat->icp6errs_redirect++; 240 return; 241 } 242 stat->icp6errs_unknown++; 243 } 244 245 /* 246 * Generate an error packet of type error in response to bad IP6 packet. 247 */ 248 void 249 icmp6_error(struct mbuf *m, int type, int code, int param) 250 { 251 struct ip6_hdr *oip6, *nip6; 252 struct icmp6_hdr *icmp6; 253 u_int preplen; 254 int off; 255 int nxt; 256 257 icmp6stat.icp6s_error++; 258 259 /* count per-type-code statistics */ 260 icmp6_errcount(&icmp6stat.icp6s_outerrhist, type, code); 261 262 #ifdef M_DECRYPTED /*not openbsd*/ 263 if (m->m_flags & M_DECRYPTED) { 264 icmp6stat.icp6s_canterror++; 265 goto freeit; 266 } 267 #endif 268 269 #ifndef PULLDOWN_TEST 270 IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), ); 271 #else 272 if (m->m_len < sizeof(struct ip6_hdr)) { 273 m = m_pullup(m, sizeof(struct ip6_hdr)); 274 if (m == NULL) 275 return; 276 } 277 #endif 278 oip6 = mtod(m, struct ip6_hdr *); 279 280 /* 281 * Multicast destination check. For unrecognized option errors, 282 * this check has already done in ip6_unknown_opt(), so we can 283 * check only for other errors. 284 */ 285 if ((m->m_flags & (M_BCAST|M_MCAST) || 286 IN6_IS_ADDR_MULTICAST(&oip6->ip6_dst)) && 287 (type != ICMP6_PACKET_TOO_BIG && 288 (type != ICMP6_PARAM_PROB || 289 code != ICMP6_PARAMPROB_OPTION))) 290 goto freeit; 291 292 /* Source address check. XXX: the case of anycast source? */ 293 if (IN6_IS_ADDR_UNSPECIFIED(&oip6->ip6_src) || 294 IN6_IS_ADDR_MULTICAST(&oip6->ip6_src)) 295 goto freeit; 296 297 /* 298 * If we are about to send ICMPv6 against ICMPv6 error/redirect, 299 * don't do it. 300 */ 301 nxt = -1; 302 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); 303 if (off >= 0 && nxt == IPPROTO_ICMPV6) { 304 struct icmp6_hdr *icp; 305 306 #ifndef PULLDOWN_TEST 307 IP6_EXTHDR_CHECK(m, 0, off + sizeof(struct icmp6_hdr), ); 308 icp = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 309 #else 310 IP6_EXTHDR_GET(icp, struct icmp6_hdr *, m, off, 311 sizeof(*icp)); 312 if (icp == NULL) { 313 icmp6stat.icp6s_tooshort++; 314 return; 315 } 316 #endif 317 if (icp->icmp6_type < ICMP6_ECHO_REQUEST || 318 icp->icmp6_type == ND_REDIRECT) { 319 /* 320 * ICMPv6 error 321 * Special case: for redirect (which is 322 * informational) we must not send icmp6 error. 323 */ 324 icmp6stat.icp6s_canterror++; 325 goto freeit; 326 } else { 327 /* ICMPv6 informational - send the error */ 328 } 329 } else { 330 /* non-ICMPv6 - send the error */ 331 } 332 333 oip6 = mtod(m, struct ip6_hdr *); /* adjust pointer */ 334 335 /* Finally, do rate limitation check. */ 336 if (icmp6_ratelimit(&oip6->ip6_src, type, code)) { 337 icmp6stat.icp6s_toofreq++; 338 goto freeit; 339 } 340 341 /* 342 * OK, ICMP6 can be generated. 343 */ 344 345 if (m->m_pkthdr.len >= ICMPV6_PLD_MAXLEN) 346 m_adj(m, ICMPV6_PLD_MAXLEN - m->m_pkthdr.len); 347 348 preplen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 349 M_PREPEND(m, preplen, MB_DONTWAIT); 350 if (m && m->m_len < preplen) 351 m = m_pullup(m, preplen); 352 if (m == NULL) { 353 nd6log((LOG_DEBUG, "ENOBUFS in icmp6_error %d\n", __LINE__)); 354 return; 355 } 356 357 nip6 = mtod(m, struct ip6_hdr *); 358 nip6->ip6_src = oip6->ip6_src; 359 nip6->ip6_dst = oip6->ip6_dst; 360 361 if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_src)) 362 oip6->ip6_src.s6_addr16[1] = 0; 363 if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_dst)) 364 oip6->ip6_dst.s6_addr16[1] = 0; 365 366 icmp6 = (struct icmp6_hdr *)(nip6 + 1); 367 icmp6->icmp6_type = type; 368 icmp6->icmp6_code = code; 369 icmp6->icmp6_pptr = htonl((u_int32_t)param); 370 371 /* 372 * icmp6_reflect() is designed to be in the input path. 373 * icmp6_error() can be called from both input and outut path, 374 * and if we are in output path rcvif could contain bogus value. 375 * clear m->m_pkthdr.rcvif for safety, we should have enough scope 376 * information in ip header (nip6). 377 */ 378 m->m_pkthdr.rcvif = NULL; 379 380 icmp6stat.icp6s_outhist[type]++; 381 icmp6_reflect(m, sizeof(struct ip6_hdr)); /* header order: IPv6 - ICMPv6 */ 382 383 return; 384 385 freeit: 386 /* 387 * If we can't tell wheter or not we can generate ICMP6, free it. 388 */ 389 m_freem(m); 390 } 391 392 /* 393 * Process a received ICMP6 message. 394 */ 395 int 396 icmp6_input(struct mbuf **mp, int *offp, int proto) 397 { 398 struct mbuf *m = *mp, *n; 399 struct ip6_hdr *ip6, *nip6; 400 struct icmp6_hdr *icmp6, *nicmp6; 401 int off = *offp; 402 int icmp6len = m->m_pkthdr.len - *offp; 403 int code, sum, noff; 404 405 #ifndef PULLDOWN_TEST 406 IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_hdr), IPPROTO_DONE); 407 /* m might change if M_LOOP. So, call mtod after this */ 408 #endif 409 410 /* 411 * Locate icmp6 structure in mbuf, and check 412 * that not corrupted and of at least minimum length 413 */ 414 415 ip6 = mtod(m, struct ip6_hdr *); 416 if (icmp6len < sizeof(struct icmp6_hdr)) { 417 icmp6stat.icp6s_tooshort++; 418 goto freeit; 419 } 420 421 /* 422 * calculate the checksum 423 */ 424 #ifndef PULLDOWN_TEST 425 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off); 426 #else 427 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 428 if (icmp6 == NULL) { 429 icmp6stat.icp6s_tooshort++; 430 return IPPROTO_DONE; 431 } 432 #endif 433 code = icmp6->icmp6_code; 434 435 if ((sum = in6_cksum(m, IPPROTO_ICMPV6, off, icmp6len)) != 0) { 436 nd6log((LOG_ERR, 437 "ICMP6 checksum error(%d|%x) %s\n", 438 icmp6->icmp6_type, sum, ip6_sprintf(&ip6->ip6_src))); 439 icmp6stat.icp6s_checksum++; 440 goto freeit; 441 } 442 443 if (faithprefix_p != NULL && (*faithprefix_p)(&ip6->ip6_dst)) { 444 /* 445 * Deliver very specific ICMP6 type only. 446 * This is important to deilver TOOBIG. Otherwise PMTUD 447 * will not work. 448 */ 449 switch (icmp6->icmp6_type) { 450 case ICMP6_DST_UNREACH: 451 case ICMP6_PACKET_TOO_BIG: 452 case ICMP6_TIME_EXCEEDED: 453 break; 454 default: 455 goto freeit; 456 } 457 } 458 459 icmp6stat.icp6s_inhist[icmp6->icmp6_type]++; 460 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_msg); 461 if (icmp6->icmp6_type < ICMP6_INFOMSG_MASK) 462 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_error); 463 464 switch (icmp6->icmp6_type) { 465 case ICMP6_DST_UNREACH: 466 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_dstunreach); 467 switch (code) { 468 case ICMP6_DST_UNREACH_NOROUTE: 469 code = PRC_UNREACH_NET; 470 break; 471 case ICMP6_DST_UNREACH_ADMIN: 472 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_adminprohib); 473 code = PRC_UNREACH_PROTOCOL; /* is this a good code? */ 474 break; 475 case ICMP6_DST_UNREACH_ADDR: 476 code = PRC_HOSTDEAD; 477 break; 478 #ifdef COMPAT_RFC1885 479 case ICMP6_DST_UNREACH_NOTNEIGHBOR: 480 code = PRC_UNREACH_SRCFAIL; 481 break; 482 #else 483 case ICMP6_DST_UNREACH_BEYONDSCOPE: 484 /* I mean "source address was incorrect." */ 485 code = PRC_PARAMPROB; 486 break; 487 #endif 488 case ICMP6_DST_UNREACH_NOPORT: 489 code = PRC_UNREACH_PORT; 490 break; 491 default: 492 goto badcode; 493 } 494 goto deliver; 495 break; 496 497 case ICMP6_PACKET_TOO_BIG: 498 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_pkttoobig); 499 if (code != 0) 500 goto badcode; 501 502 code = PRC_MSGSIZE; 503 504 /* 505 * Updating the path MTU will be done after examining 506 * intermediate extension headers. 507 */ 508 goto deliver; 509 break; 510 511 case ICMP6_TIME_EXCEEDED: 512 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_timeexceed); 513 switch (code) { 514 case ICMP6_TIME_EXCEED_TRANSIT: 515 case ICMP6_TIME_EXCEED_REASSEMBLY: 516 code += PRC_TIMXCEED_INTRANS; 517 break; 518 default: 519 goto badcode; 520 } 521 goto deliver; 522 break; 523 524 case ICMP6_PARAM_PROB: 525 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_paramprob); 526 switch (code) { 527 case ICMP6_PARAMPROB_NEXTHEADER: 528 code = PRC_UNREACH_PROTOCOL; 529 break; 530 case ICMP6_PARAMPROB_HEADER: 531 case ICMP6_PARAMPROB_OPTION: 532 code = PRC_PARAMPROB; 533 break; 534 default: 535 goto badcode; 536 } 537 goto deliver; 538 break; 539 540 case ICMP6_ECHO_REQUEST: 541 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echo); 542 if (code != 0) 543 goto badcode; 544 if ((n = m_copy(m, 0, M_COPYALL)) == NULL) { 545 /* Give up remote */ 546 break; 547 } 548 if ((n->m_flags & M_EXT) != 0 549 || n->m_len < off + sizeof(struct icmp6_hdr)) { 550 struct mbuf *n0 = n; 551 const int maxlen = sizeof(*nip6) + sizeof(*nicmp6); 552 int n0len; 553 554 /* 555 * Prepare an internal mbuf. m_pullup() doesn't 556 * always copy the length we specified. 557 */ 558 if (maxlen >= MCLBYTES) { 559 /* Give up remote */ 560 m_freem(n0); 561 break; 562 } 563 MGETHDR(n, MB_DONTWAIT, n0->m_type); 564 n0len = n0->m_pkthdr.len; /* save for use below */ 565 if (n) 566 M_MOVE_PKTHDR(n, n0); 567 if (n && maxlen >= MHLEN) { 568 MCLGET(n, MB_DONTWAIT); 569 if ((n->m_flags & M_EXT) == 0) { 570 m_free(n); 571 n = NULL; 572 } 573 } 574 if (n == NULL) { 575 /* Give up remote */ 576 m_freem(n0); 577 break; 578 } 579 /* 580 * Copy IPv6 and ICMPv6 only. 581 */ 582 nip6 = mtod(n, struct ip6_hdr *); 583 bcopy(ip6, nip6, sizeof(struct ip6_hdr)); 584 nicmp6 = (struct icmp6_hdr *)(nip6 + 1); 585 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr)); 586 noff = sizeof(struct ip6_hdr); 587 /* new mbuf contains only ipv6+icmpv6 headers */ 588 n->m_len = noff + sizeof(struct icmp6_hdr); 589 /* 590 * Adjust mbuf. ip6_plen will be adjusted in 591 * ip6_output(). 592 */ 593 m_adj(n0, off + sizeof(struct icmp6_hdr)); 594 /* recalculate complete packet size */ 595 n->m_pkthdr.len = n0len + (noff - off); 596 n->m_next = n0; 597 } else { 598 nip6 = mtod(n, struct ip6_hdr *); 599 nicmp6 = (struct icmp6_hdr *)((caddr_t)nip6 + off); 600 noff = off; 601 } 602 nicmp6->icmp6_type = ICMP6_ECHO_REPLY; 603 nicmp6->icmp6_code = 0; 604 if (n) { 605 icmp6stat.icp6s_reflect++; 606 icmp6stat.icp6s_outhist[ICMP6_ECHO_REPLY]++; 607 icmp6_reflect(n, noff); 608 } 609 break; 610 611 case ICMP6_ECHO_REPLY: 612 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echoreply); 613 if (code != 0) 614 goto badcode; 615 break; 616 617 case MLD_LISTENER_QUERY: 618 case MLD_LISTENER_REPORT: 619 if (icmp6len < sizeof(struct mld_hdr)) 620 goto badlen; 621 if (icmp6->icmp6_type == MLD_LISTENER_QUERY) /* XXX: ugly... */ 622 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldquery); 623 else 624 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldreport); 625 if ((n = m_copym(m, 0, M_COPYALL, MB_DONTWAIT)) == NULL) { 626 /* give up local */ 627 mld6_input(m, off); 628 m = NULL; 629 goto freeit; 630 } 631 mld6_input(n, off); 632 /* m stays. */ 633 break; 634 635 case MLD_LISTENER_DONE: 636 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mlddone); 637 if (icmp6len < sizeof(struct mld_hdr)) /* necessary? */ 638 goto badlen; 639 break; /* nothing to be done in kernel */ 640 641 case MLD_MTRACE_RESP: 642 case MLD_MTRACE: 643 /* XXX: these two are experimental. not officially defind. */ 644 /* XXX: per-interface statistics? */ 645 break; /* just pass it to applications */ 646 647 case ICMP6_WRUREQUEST: /* ICMP6_FQDN_QUERY */ 648 { 649 enum { WRU, FQDN } mode; 650 651 if (!icmp6_nodeinfo) 652 break; 653 654 if (icmp6len == sizeof(struct icmp6_hdr) + 4) 655 mode = WRU; 656 else if (icmp6len >= sizeof(struct icmp6_nodeinfo)) 657 mode = FQDN; 658 else 659 goto badlen; 660 661 #define hostnamelen strlen(hostname) 662 if (mode == FQDN) { 663 #ifndef PULLDOWN_TEST 664 IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_nodeinfo), 665 IPPROTO_DONE); 666 #endif 667 n = m_copy(m, 0, M_COPYALL); 668 if (n) 669 n = ni6_input(n, off); 670 /* XXX meaningless if n == NULL */ 671 noff = sizeof(struct ip6_hdr); 672 } else { 673 u_char *p; 674 int maxlen, maxhlen; 675 676 if ((icmp6_nodeinfo & 5) != 5) 677 break; 678 679 if (code != 0) 680 goto badcode; 681 maxlen = sizeof(*nip6) + sizeof(*nicmp6) + 4; 682 if (maxlen >= MCLBYTES) { 683 /* Give up remote */ 684 break; 685 } 686 MGETHDR(n, MB_DONTWAIT, m->m_type); 687 if (n && maxlen > MHLEN) { 688 MCLGET(n, MB_DONTWAIT); 689 if ((n->m_flags & M_EXT) == 0) { 690 m_free(n); 691 n = NULL; 692 } 693 } 694 if (!m_dup_pkthdr(n, m, MB_DONTWAIT)) { 695 /* 696 * Previous code did a blind M_COPY_PKTHDR 697 * and said "just for rcvif". If true, then 698 * we could tolerate the dup failing (due to 699 * the deep copy of the tag chain). For now 700 * be conservative and just fail. 701 */ 702 m_free(n); 703 n = NULL; 704 } 705 if (n == NULL) { 706 /* Give up remote */ 707 break; 708 } 709 n->m_pkthdr.rcvif = NULL; 710 n->m_len = 0; 711 maxhlen = M_TRAILINGSPACE(n) - maxlen; 712 if (maxhlen > hostnamelen) 713 maxhlen = hostnamelen; 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 bcopy(hostname, p + 4, maxhlen); /* meaningless TTL */ 724 noff = sizeof(struct ip6_hdr); 725 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) + 726 sizeof(struct icmp6_hdr) + 4 + maxhlen; 727 nicmp6->icmp6_type = ICMP6_WRUREPLY; 728 nicmp6->icmp6_code = 0; 729 } 730 #undef hostnamelen 731 if (n) { 732 icmp6stat.icp6s_reflect++; 733 icmp6stat.icp6s_outhist[ICMP6_WRUREPLY]++; 734 icmp6_reflect(n, noff); 735 } 736 break; 737 } 738 739 case ICMP6_WRUREPLY: 740 if (code != 0) 741 goto badcode; 742 break; 743 744 case ND_ROUTER_SOLICIT: 745 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routersolicit); 746 if (code != 0) 747 goto badcode; 748 if (icmp6len < sizeof(struct nd_router_solicit)) 749 goto badlen; 750 if ((n = m_copym(m, 0, M_COPYALL, MB_DONTWAIT)) == NULL) { 751 /* give up local */ 752 nd6_rs_input(m, off, icmp6len); 753 m = NULL; 754 goto freeit; 755 } 756 nd6_rs_input(n, off, icmp6len); 757 /* m stays. */ 758 break; 759 760 case ND_ROUTER_ADVERT: 761 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routeradvert); 762 if (code != 0) 763 goto badcode; 764 if (icmp6len < sizeof(struct nd_router_advert)) 765 goto badlen; 766 if ((n = m_copym(m, 0, M_COPYALL, MB_DONTWAIT)) == NULL) { 767 /* give up local */ 768 nd6_ra_input(m, off, icmp6len); 769 m = NULL; 770 goto freeit; 771 } 772 nd6_ra_input(n, off, icmp6len); 773 /* m stays. */ 774 break; 775 776 case ND_NEIGHBOR_SOLICIT: 777 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighborsolicit); 778 if (code != 0) 779 goto badcode; 780 if (icmp6len < sizeof(struct nd_neighbor_solicit)) 781 goto badlen; 782 if ((n = m_copym(m, 0, M_COPYALL, MB_DONTWAIT)) == NULL) { 783 /* give up local */ 784 nd6_ns_input(m, off, icmp6len); 785 m = NULL; 786 goto freeit; 787 } 788 nd6_ns_input(n, off, icmp6len); 789 /* m stays. */ 790 break; 791 792 case ND_NEIGHBOR_ADVERT: 793 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighboradvert); 794 if (code != 0) 795 goto badcode; 796 if (icmp6len < sizeof(struct nd_neighbor_advert)) 797 goto badlen; 798 if ((n = m_copym(m, 0, M_COPYALL, MB_DONTWAIT)) == NULL) { 799 /* give up local */ 800 nd6_na_input(m, off, icmp6len); 801 m = NULL; 802 goto freeit; 803 } 804 nd6_na_input(n, off, icmp6len); 805 /* m stays. */ 806 break; 807 808 case ND_REDIRECT: 809 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_redirect); 810 if (code != 0) 811 goto badcode; 812 if (icmp6len < sizeof(struct nd_redirect)) 813 goto badlen; 814 if ((n = m_copym(m, 0, M_COPYALL, MB_DONTWAIT)) == NULL) { 815 /* give up local */ 816 icmp6_redirect_input(m, off); 817 m = NULL; 818 goto freeit; 819 } 820 icmp6_redirect_input(n, off); 821 /* m stays. */ 822 break; 823 824 case ICMP6_ROUTER_RENUMBERING: 825 if (code != ICMP6_ROUTER_RENUMBERING_COMMAND && 826 code != ICMP6_ROUTER_RENUMBERING_RESULT) 827 goto badcode; 828 if (icmp6len < sizeof(struct icmp6_router_renum)) 829 goto badlen; 830 break; 831 832 default: 833 nd6log((LOG_DEBUG, 834 "icmp6_input: unknown type %d(src=%s, dst=%s, ifid=%d)\n", 835 icmp6->icmp6_type, ip6_sprintf(&ip6->ip6_src), 836 ip6_sprintf(&ip6->ip6_dst), 837 m->m_pkthdr.rcvif ? m->m_pkthdr.rcvif->if_index : 0)); 838 if (icmp6->icmp6_type < ICMP6_ECHO_REQUEST) { 839 /* ICMPv6 error: MUST deliver it by spec... */ 840 code = PRC_NCMDS; 841 /* deliver */ 842 } else { 843 /* ICMPv6 informational: MUST not deliver */ 844 break; 845 } 846 deliver: 847 if (icmp6_notify_error(m, off, icmp6len, code)) { 848 /* In this case, m should've been freed. */ 849 return(IPPROTO_DONE); 850 } 851 break; 852 853 badcode: 854 icmp6stat.icp6s_badcode++; 855 break; 856 857 badlen: 858 icmp6stat.icp6s_badlen++; 859 break; 860 } 861 862 /* deliver the packet to appropriate sockets */ 863 icmp6_rip6_input(&m, *offp); 864 865 return IPPROTO_DONE; 866 867 freeit: 868 m_freem(m); 869 return IPPROTO_DONE; 870 } 871 872 static int 873 icmp6_notify_error(struct mbuf *m, int off, int icmp6len, int code) 874 { 875 struct icmp6_hdr *icmp6; 876 struct ip6_hdr *eip6; 877 u_int32_t notifymtu; 878 struct sockaddr_in6 icmp6src, icmp6dst; 879 880 if (icmp6len < sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr)) { 881 icmp6stat.icp6s_tooshort++; 882 goto freeit; 883 } 884 #ifndef PULLDOWN_TEST 885 IP6_EXTHDR_CHECK(m, off, 886 sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr), 887 -1); 888 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 889 #else 890 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, 891 sizeof(*icmp6) + sizeof(struct ip6_hdr)); 892 if (icmp6 == NULL) { 893 icmp6stat.icp6s_tooshort++; 894 return(-1); 895 } 896 #endif 897 eip6 = (struct ip6_hdr *)(icmp6 + 1); 898 899 /* Detect the upper level protocol */ 900 { 901 void (*ctlfunc) (int, struct sockaddr *, void *); 902 u_int8_t nxt = eip6->ip6_nxt; 903 int eoff = off + sizeof(struct icmp6_hdr) + 904 sizeof(struct ip6_hdr); 905 struct ip6ctlparam ip6cp; 906 struct in6_addr *finaldst = NULL; 907 int icmp6type = icmp6->icmp6_type; 908 struct ip6_frag *fh; 909 struct ip6_rthdr *rth; 910 struct ip6_rthdr0 *rth0; 911 int rthlen; 912 913 while (1) { /* XXX: should avoid infinite loop explicitly? */ 914 struct ip6_ext *eh; 915 916 switch (nxt) { 917 case IPPROTO_HOPOPTS: 918 case IPPROTO_DSTOPTS: 919 case IPPROTO_AH: 920 #ifndef PULLDOWN_TEST 921 IP6_EXTHDR_CHECK(m, 0, eoff + 922 sizeof(struct ip6_ext), 923 -1); 924 eh = (struct ip6_ext *)(mtod(m, caddr_t) 925 + eoff); 926 #else 927 IP6_EXTHDR_GET(eh, struct ip6_ext *, m, 928 eoff, sizeof(*eh)); 929 if (eh == NULL) { 930 icmp6stat.icp6s_tooshort++; 931 return(-1); 932 } 933 #endif 934 935 if (nxt == IPPROTO_AH) 936 eoff += (eh->ip6e_len + 2) << 2; 937 else 938 eoff += (eh->ip6e_len + 1) << 3; 939 nxt = eh->ip6e_nxt; 940 break; 941 case IPPROTO_ROUTING: 942 /* 943 * When the erroneous packet contains a 944 * routing header, we should examine the 945 * header to determine the final destination. 946 * Otherwise, we can't properly update 947 * information that depends on the final 948 * destination (e.g. path MTU). 949 */ 950 #ifndef PULLDOWN_TEST 951 IP6_EXTHDR_CHECK(m, 0, eoff + sizeof(*rth), 952 -1); 953 rth = (struct ip6_rthdr *)(mtod(m, caddr_t) 954 + eoff); 955 #else 956 IP6_EXTHDR_GET(rth, struct ip6_rthdr *, m, 957 eoff, sizeof(*rth)); 958 if (rth == NULL) { 959 icmp6stat.icp6s_tooshort++; 960 return(-1); 961 } 962 #endif 963 rthlen = (rth->ip6r_len + 1) << 3; 964 /* 965 * XXX: currently there is no 966 * officially defined type other 967 * than type-0. 968 * Note that if the segment left field 969 * is 0, all intermediate hops must 970 * have been passed. 971 */ 972 if (rth->ip6r_segleft && 973 rth->ip6r_type == IPV6_RTHDR_TYPE_0) { 974 int hops; 975 976 #ifndef PULLDOWN_TEST 977 IP6_EXTHDR_CHECK(m, 0, eoff + rthlen, 978 -1); 979 rth0 = (struct ip6_rthdr0 *)(mtod(m, caddr_t) + eoff); 980 #else 981 IP6_EXTHDR_GET(rth0, 982 struct ip6_rthdr0 *, m, 983 eoff, rthlen); 984 if (rth0 == NULL) { 985 icmp6stat.icp6s_tooshort++; 986 return(-1); 987 } 988 #endif 989 /* just ignore a bogus header */ 990 if ((rth0->ip6r0_len % 2) == 0 && 991 (hops = rth0->ip6r0_len/2)) 992 finaldst = (struct in6_addr *)(rth0 + 1) + (hops - 1); 993 } 994 eoff += rthlen; 995 nxt = rth->ip6r_nxt; 996 break; 997 case IPPROTO_FRAGMENT: 998 #ifndef PULLDOWN_TEST 999 IP6_EXTHDR_CHECK(m, 0, eoff + 1000 sizeof(struct ip6_frag), 1001 -1); 1002 fh = (struct ip6_frag *)(mtod(m, caddr_t) 1003 + eoff); 1004 #else 1005 IP6_EXTHDR_GET(fh, struct ip6_frag *, m, 1006 eoff, sizeof(*fh)); 1007 if (fh == NULL) { 1008 icmp6stat.icp6s_tooshort++; 1009 return(-1); 1010 } 1011 #endif 1012 /* 1013 * Data after a fragment header is meaningless 1014 * unless it is the first fragment, but 1015 * we'll go to the notify label for path MTU 1016 * discovery. 1017 */ 1018 if (fh->ip6f_offlg & IP6F_OFF_MASK) 1019 goto notify; 1020 1021 eoff += sizeof(struct ip6_frag); 1022 nxt = fh->ip6f_nxt; 1023 break; 1024 default: 1025 /* 1026 * This case includes ESP and the No Next 1027 * Header. In such cases going to the notify 1028 * label does not have any meaning 1029 * (i.e. ctlfunc will be NULL), but we go 1030 * anyway since we might have to update 1031 * path MTU information. 1032 */ 1033 goto notify; 1034 } 1035 } 1036 notify: 1037 #ifndef PULLDOWN_TEST 1038 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 1039 #else 1040 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, 1041 sizeof(*icmp6) + sizeof(struct ip6_hdr)); 1042 if (icmp6 == NULL) { 1043 icmp6stat.icp6s_tooshort++; 1044 return(-1); 1045 } 1046 #endif 1047 1048 eip6 = (struct ip6_hdr *)(icmp6 + 1); 1049 bzero(&icmp6dst, sizeof(icmp6dst)); 1050 icmp6dst.sin6_len = sizeof(struct sockaddr_in6); 1051 icmp6dst.sin6_family = AF_INET6; 1052 if (finaldst == NULL) 1053 icmp6dst.sin6_addr = eip6->ip6_dst; 1054 else 1055 icmp6dst.sin6_addr = *finaldst; 1056 icmp6dst.sin6_scope_id = in6_addr2scopeid(m->m_pkthdr.rcvif, 1057 &icmp6dst.sin6_addr); 1058 #ifndef SCOPEDROUTING 1059 if (in6_embedscope(&icmp6dst.sin6_addr, &icmp6dst, 1060 NULL, NULL)) { 1061 /* should be impossbile */ 1062 nd6log((LOG_DEBUG, 1063 "icmp6_notify_error: in6_embedscope failed\n")); 1064 goto freeit; 1065 } 1066 #endif 1067 1068 /* 1069 * retrieve parameters from the inner IPv6 header, and convert 1070 * them into sockaddr structures. 1071 */ 1072 bzero(&icmp6src, sizeof(icmp6src)); 1073 icmp6src.sin6_len = sizeof(struct sockaddr_in6); 1074 icmp6src.sin6_family = AF_INET6; 1075 icmp6src.sin6_addr = eip6->ip6_src; 1076 icmp6src.sin6_scope_id = in6_addr2scopeid(m->m_pkthdr.rcvif, 1077 &icmp6src.sin6_addr); 1078 #ifndef SCOPEDROUTING 1079 if (in6_embedscope(&icmp6src.sin6_addr, &icmp6src, 1080 NULL, NULL)) { 1081 /* should be impossbile */ 1082 nd6log((LOG_DEBUG, 1083 "icmp6_notify_error: in6_embedscope failed\n")); 1084 goto freeit; 1085 } 1086 #endif 1087 icmp6src.sin6_flowinfo = 1088 (eip6->ip6_flow & IPV6_FLOWLABEL_MASK); 1089 1090 if (finaldst == NULL) 1091 finaldst = &eip6->ip6_dst; 1092 ip6cp.ip6c_m = m; 1093 ip6cp.ip6c_icmp6 = icmp6; 1094 ip6cp.ip6c_ip6 = (struct ip6_hdr *)(icmp6 + 1); 1095 ip6cp.ip6c_off = eoff; 1096 ip6cp.ip6c_finaldst = finaldst; 1097 ip6cp.ip6c_src = &icmp6src; 1098 ip6cp.ip6c_nxt = nxt; 1099 1100 if (icmp6type == ICMP6_PACKET_TOO_BIG) { 1101 notifymtu = ntohl(icmp6->icmp6_mtu); 1102 ip6cp.ip6c_cmdarg = (void *)¬ifymtu; 1103 icmp6_mtudisc_update(&ip6cp, 1); /*XXX*/ 1104 } 1105 1106 ctlfunc = (void (*) (int, struct sockaddr *, void *)) 1107 (inet6sw[ip6_protox[nxt]].pr_ctlinput); 1108 if (ctlfunc) { 1109 (void) (*ctlfunc)(code, (struct sockaddr *)&icmp6dst, 1110 &ip6cp); 1111 } 1112 } 1113 return(0); 1114 1115 freeit: 1116 m_freem(m); 1117 return(-1); 1118 } 1119 1120 void 1121 icmp6_mtudisc_update(struct ip6ctlparam *ip6cp, int validated) 1122 { 1123 struct in6_addr *dst = ip6cp->ip6c_finaldst; 1124 struct icmp6_hdr *icmp6 = ip6cp->ip6c_icmp6; 1125 struct mbuf *m = ip6cp->ip6c_m; /* will be necessary for scope issue */ 1126 u_int mtu = ntohl(icmp6->icmp6_mtu); 1127 struct rtentry *rt = NULL; 1128 struct sockaddr_in6 sin6; 1129 1130 if (!validated) 1131 return; 1132 1133 bzero(&sin6, sizeof(sin6)); 1134 sin6.sin6_family = PF_INET6; 1135 sin6.sin6_len = sizeof(struct sockaddr_in6); 1136 sin6.sin6_addr = *dst; 1137 /* XXX normally, this won't happen */ 1138 if (IN6_IS_ADDR_LINKLOCAL(dst)) { 1139 sin6.sin6_addr.s6_addr16[1] = 1140 htons(m->m_pkthdr.rcvif->if_index); 1141 } 1142 /* sin6.sin6_scope_id = XXX: should be set if DST is a scoped addr */ 1143 rt = rtpurelookup((struct sockaddr *)&sin6); 1144 1145 if (rt != NULL && (rt->rt_flags & RTF_HOST) && 1146 !(rt->rt_rmx.rmx_locks & RTV_MTU)) { 1147 if (mtu < IPV6_MMTU) { /* XXX */ 1148 rt->rt_rmx.rmx_locks |= RTV_MTU; 1149 } else if (mtu < rt->rt_ifp->if_mtu && 1150 rt->rt_rmx.rmx_mtu > mtu) { 1151 icmp6stat.icp6s_pmtuchg++; 1152 rt->rt_rmx.rmx_mtu = mtu; 1153 } 1154 } 1155 if (rt) 1156 --rt->rt_refcnt; 1157 } 1158 1159 /* 1160 * Process a Node Information Query packet, based on 1161 * draft-ietf-ipngwg-icmp-name-lookups-07. 1162 * 1163 * Spec incompatibilities: 1164 * - IPv6 Subject address handling 1165 * - IPv4 Subject address handling support missing 1166 * - Proxy reply (answer even if it's not for me) 1167 * - joins NI group address at in6_ifattach() time only, does not cope 1168 * with hostname changes by sethostname(3) 1169 */ 1170 #define hostnamelen strlen(hostname) 1171 static struct mbuf * 1172 ni6_input(struct mbuf *m, int off) 1173 { 1174 struct icmp6_nodeinfo *ni6, *nni6; 1175 struct mbuf *n = NULL; 1176 u_int16_t qtype; 1177 int subjlen; 1178 int replylen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo); 1179 struct ni_reply_fqdn *fqdn; 1180 int addrs; /* for NI_QTYPE_NODEADDR */ 1181 struct ifnet *ifp = NULL; /* for NI_QTYPE_NODEADDR */ 1182 struct sockaddr_in6 sin6; /* double meaning; ip6_dst and subjectaddr */ 1183 struct sockaddr_in6 sin6_d; /* XXX: we should retrieve this from m_aux */ 1184 struct ip6_hdr *ip6; 1185 int oldfqdn = 0; /* if 1, return pascal string (03 draft) */ 1186 char *subj = NULL; 1187 struct in6_ifaddr *ia6 = NULL; 1188 1189 ip6 = mtod(m, struct ip6_hdr *); 1190 #ifndef PULLDOWN_TEST 1191 ni6 = (struct icmp6_nodeinfo *)(mtod(m, caddr_t) + off); 1192 #else 1193 IP6_EXTHDR_GET(ni6, struct icmp6_nodeinfo *, m, off, sizeof(*ni6)); 1194 if (ni6 == NULL) { 1195 /* m is already reclaimed */ 1196 return NULL; 1197 } 1198 #endif 1199 1200 /* 1201 * Validate IPv6 destination address. 1202 * 1203 * The Responder must discard the Query without further processing 1204 * unless it is one of the Responder's unicast or anycast addresses, or 1205 * a link-local scope multicast address which the Responder has joined. 1206 * [icmp-name-lookups-07, Section 4.] 1207 */ 1208 bzero(&sin6, sizeof(sin6)); 1209 sin6.sin6_family = AF_INET6; 1210 sin6.sin6_len = sizeof(struct sockaddr_in6); 1211 bcopy(&ip6->ip6_dst, &sin6.sin6_addr, sizeof(sin6.sin6_addr)); 1212 /* XXX scopeid */ 1213 if ((ia6 = (struct in6_ifaddr *)ifa_ifwithaddr((struct sockaddr *)&sin6)) != NULL) { 1214 /* unicast/anycast, fine */ 1215 if ((ia6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 1216 (icmp6_nodeinfo & 4) == 0) { 1217 nd6log((LOG_DEBUG, "ni6_input: ignore node info to " 1218 "a temporary address in %s:%d", 1219 __FILE__, __LINE__)); 1220 goto bad; 1221 } 1222 } else if (IN6_IS_ADDR_MC_LINKLOCAL(&sin6.sin6_addr)) 1223 ; /* link-local multicast, fine */ 1224 else 1225 goto bad; 1226 1227 /* validate query Subject field. */ 1228 qtype = ntohs(ni6->ni_qtype); 1229 subjlen = m->m_pkthdr.len - off - sizeof(struct icmp6_nodeinfo); 1230 switch (qtype) { 1231 case NI_QTYPE_NOOP: 1232 case NI_QTYPE_SUPTYPES: 1233 /* 07 draft */ 1234 if (ni6->ni_code == ICMP6_NI_SUBJ_FQDN && subjlen == 0) 1235 break; 1236 /* FALLTHROUGH */ 1237 case NI_QTYPE_FQDN: 1238 case NI_QTYPE_NODEADDR: 1239 switch (ni6->ni_code) { 1240 case ICMP6_NI_SUBJ_IPV6: 1241 #if ICMP6_NI_SUBJ_IPV6 != 0 1242 case 0: 1243 #endif 1244 /* 1245 * backward compatibility - try to accept 03 draft 1246 * format, where no Subject is present. 1247 */ 1248 if (qtype == NI_QTYPE_FQDN && ni6->ni_code == 0 && 1249 subjlen == 0) { 1250 oldfqdn++; 1251 break; 1252 } 1253 #if ICMP6_NI_SUBJ_IPV6 != 0 1254 if (ni6->ni_code != ICMP6_NI_SUBJ_IPV6) 1255 goto bad; 1256 #endif 1257 1258 if (subjlen != sizeof(sin6.sin6_addr)) 1259 goto bad; 1260 1261 /* 1262 * Validate Subject address. 1263 * 1264 * Not sure what exactly "address belongs to the node" 1265 * means in the spec, is it just unicast, or what? 1266 * 1267 * At this moment we consider Subject address as 1268 * "belong to the node" if the Subject address equals 1269 * to the IPv6 destination address; validation for 1270 * IPv6 destination address should have done enough 1271 * check for us. 1272 * 1273 * We do not do proxy at this moment. 1274 */ 1275 /* m_pulldown instead of copy? */ 1276 m_copydata(m, off + sizeof(struct icmp6_nodeinfo), 1277 subjlen, (caddr_t)&sin6.sin6_addr); 1278 sin6.sin6_scope_id = in6_addr2scopeid(m->m_pkthdr.rcvif, 1279 &sin6.sin6_addr); 1280 #ifndef SCOPEDROUTING 1281 in6_embedscope(&sin6.sin6_addr, &sin6, NULL, NULL); 1282 #endif 1283 bzero(&sin6_d, sizeof(sin6_d)); 1284 sin6_d.sin6_family = AF_INET6; /* not used, actually */ 1285 sin6_d.sin6_len = sizeof(sin6_d); /* ditto */ 1286 sin6_d.sin6_addr = ip6->ip6_dst; 1287 sin6_d.sin6_scope_id = in6_addr2scopeid(m->m_pkthdr.rcvif, 1288 &ip6->ip6_dst); 1289 #ifndef SCOPEDROUTING 1290 in6_embedscope(&sin6_d.sin6_addr, &sin6_d, NULL, NULL); 1291 #endif 1292 subj = (char *)&sin6; 1293 if (SA6_ARE_ADDR_EQUAL(&sin6, &sin6_d)) 1294 break; 1295 1296 /* 1297 * XXX if we are to allow other cases, we should really 1298 * be careful about scope here. 1299 * basically, we should disallow queries toward IPv6 1300 * destination X with subject Y, if scope(X) > scope(Y). 1301 * if we allow scope(X) > scope(Y), it will result in 1302 * information leakage across scope boundary. 1303 */ 1304 goto bad; 1305 1306 case ICMP6_NI_SUBJ_FQDN: 1307 /* 1308 * Validate Subject name with gethostname(3). 1309 * 1310 * The behavior may need some debate, since: 1311 * - we are not sure if the node has FQDN as 1312 * hostname (returned by gethostname(3)). 1313 * - the code does wildcard match for truncated names. 1314 * however, we are not sure if we want to perform 1315 * wildcard match, if gethostname(3) side has 1316 * truncated hostname. 1317 */ 1318 n = ni6_nametodns(hostname, hostnamelen, 0); 1319 if (!n || n->m_next || n->m_len == 0) 1320 goto bad; 1321 IP6_EXTHDR_GET(subj, char *, m, 1322 off + sizeof(struct icmp6_nodeinfo), subjlen); 1323 if (subj == NULL) 1324 goto bad; 1325 if (!ni6_dnsmatch(subj, subjlen, mtod(n, const char *), 1326 n->m_len)) { 1327 goto bad; 1328 } 1329 m_freem(n); 1330 n = NULL; 1331 break; 1332 1333 case ICMP6_NI_SUBJ_IPV4: /* XXX: to be implemented? */ 1334 default: 1335 goto bad; 1336 } 1337 break; 1338 } 1339 1340 /* refuse based on configuration. XXX ICMP6_NI_REFUSED? */ 1341 switch (qtype) { 1342 case NI_QTYPE_FQDN: 1343 if ((icmp6_nodeinfo & 1) == 0) 1344 goto bad; 1345 break; 1346 case NI_QTYPE_NODEADDR: 1347 if ((icmp6_nodeinfo & 2) == 0) 1348 goto bad; 1349 break; 1350 } 1351 1352 /* guess reply length */ 1353 switch (qtype) { 1354 case NI_QTYPE_NOOP: 1355 break; /* no reply data */ 1356 case NI_QTYPE_SUPTYPES: 1357 replylen += sizeof(u_int32_t); 1358 break; 1359 case NI_QTYPE_FQDN: 1360 /* XXX will append an mbuf */ 1361 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1362 break; 1363 case NI_QTYPE_NODEADDR: 1364 addrs = ni6_addrs(ni6, m, &ifp, subj); 1365 if ((replylen += addrs * (sizeof(struct in6_addr) + 1366 sizeof(u_int32_t))) > MCLBYTES) 1367 replylen = MCLBYTES; /* XXX: will truncate pkt later */ 1368 break; 1369 default: 1370 /* 1371 * XXX: We must return a reply with the ICMP6 code 1372 * `unknown Qtype' in this case. However we regard the case 1373 * as an FQDN query for backward compatibility. 1374 * Older versions set a random value to this field, 1375 * so it rarely varies in the defined qtypes. 1376 * But the mechanism is not reliable... 1377 * maybe we should obsolete older versions. 1378 */ 1379 qtype = NI_QTYPE_FQDN; 1380 /* XXX will append an mbuf */ 1381 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1382 oldfqdn++; 1383 break; 1384 } 1385 1386 /* allocate an mbuf to reply. */ 1387 MGETHDR(n, MB_DONTWAIT, m->m_type); 1388 if (n == NULL) { 1389 m_freem(m); 1390 return(NULL); 1391 } 1392 M_MOVE_PKTHDR(n, m); /* just for recvif */ 1393 if (replylen > MHLEN) { 1394 if (replylen > MCLBYTES) { 1395 /* 1396 * XXX: should we try to allocate more? But MCLBYTES 1397 * is probably much larger than IPV6_MMTU... 1398 */ 1399 goto bad; 1400 } 1401 MCLGET(n, MB_DONTWAIT); 1402 if ((n->m_flags & M_EXT) == 0) { 1403 goto bad; 1404 } 1405 } 1406 n->m_pkthdr.len = n->m_len = replylen; 1407 1408 /* copy mbuf header and IPv6 + Node Information base headers */ 1409 bcopy(mtod(m, caddr_t), mtod(n, caddr_t), sizeof(struct ip6_hdr)); 1410 nni6 = (struct icmp6_nodeinfo *)(mtod(n, struct ip6_hdr *) + 1); 1411 bcopy((caddr_t)ni6, (caddr_t)nni6, sizeof(struct icmp6_nodeinfo)); 1412 1413 /* qtype dependent procedure */ 1414 switch (qtype) { 1415 case NI_QTYPE_NOOP: 1416 nni6->ni_code = ICMP6_NI_SUCCESS; 1417 nni6->ni_flags = 0; 1418 break; 1419 case NI_QTYPE_SUPTYPES: 1420 { 1421 u_int32_t v; 1422 nni6->ni_code = ICMP6_NI_SUCCESS; 1423 nni6->ni_flags = htons(0x0000); /* raw bitmap */ 1424 /* supports NOOP, SUPTYPES, FQDN, and NODEADDR */ 1425 v = (u_int32_t)htonl(0x0000000f); 1426 bcopy(&v, nni6 + 1, sizeof(u_int32_t)); 1427 break; 1428 } 1429 case NI_QTYPE_FQDN: 1430 nni6->ni_code = ICMP6_NI_SUCCESS; 1431 fqdn = (struct ni_reply_fqdn *)(mtod(n, caddr_t) + 1432 sizeof(struct ip6_hdr) + 1433 sizeof(struct icmp6_nodeinfo)); 1434 nni6->ni_flags = 0; /* XXX: meaningless TTL */ 1435 fqdn->ni_fqdn_ttl = 0; /* ditto. */ 1436 /* 1437 * XXX do we really have FQDN in variable "hostname"? 1438 */ 1439 n->m_next = ni6_nametodns(hostname, hostnamelen, oldfqdn); 1440 if (n->m_next == NULL) 1441 goto bad; 1442 /* XXX we assume that n->m_next is not a chain */ 1443 if (n->m_next->m_next != NULL) 1444 goto bad; 1445 n->m_pkthdr.len += n->m_next->m_len; 1446 break; 1447 case NI_QTYPE_NODEADDR: 1448 { 1449 int lenlim, copied; 1450 1451 nni6->ni_code = ICMP6_NI_SUCCESS; 1452 n->m_pkthdr.len = n->m_len = 1453 sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo); 1454 lenlim = M_TRAILINGSPACE(n); 1455 copied = ni6_store_addrs(ni6, nni6, ifp, lenlim); 1456 /* XXX: reset mbuf length */ 1457 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) + 1458 sizeof(struct icmp6_nodeinfo) + copied; 1459 break; 1460 } 1461 default: 1462 break; /* XXX impossible! */ 1463 } 1464 1465 nni6->ni_type = ICMP6_NI_REPLY; 1466 m_freem(m); 1467 return(n); 1468 1469 bad: 1470 m_freem(m); 1471 if (n) 1472 m_freem(n); 1473 return(NULL); 1474 } 1475 #undef hostnamelen 1476 1477 /* 1478 * make a mbuf with DNS-encoded string. no compression support. 1479 * 1480 * XXX names with less than 2 dots (like "foo" or "foo.section") will be 1481 * treated as truncated name (two \0 at the end). this is a wild guess. 1482 */ 1483 static struct mbuf * 1484 ni6_nametodns(const char *name, int namelen, 1485 int old) /* return pascal string if non-zero */ 1486 { 1487 struct mbuf *m; 1488 char *cp, *ep; 1489 const char *p, *q; 1490 int i, len, nterm; 1491 1492 if (old) 1493 len = namelen + 1; 1494 else 1495 len = MCLBYTES; 1496 1497 /* because MAXHOSTNAMELEN is usually 256, we use cluster mbuf */ 1498 MGET(m, MB_DONTWAIT, MT_DATA); 1499 if (m && len > MLEN) { 1500 MCLGET(m, MB_DONTWAIT); 1501 if ((m->m_flags & M_EXT) == 0) 1502 goto fail; 1503 } 1504 if (!m) 1505 goto fail; 1506 m->m_next = NULL; 1507 1508 if (old) { 1509 m->m_len = len; 1510 *mtod(m, char *) = namelen; 1511 bcopy(name, mtod(m, char *) + 1, namelen); 1512 return m; 1513 } else { 1514 m->m_len = 0; 1515 cp = mtod(m, char *); 1516 ep = mtod(m, char *) + M_TRAILINGSPACE(m); 1517 1518 /* if not certain about my name, return empty buffer */ 1519 if (namelen == 0) 1520 return m; 1521 1522 /* 1523 * guess if it looks like shortened hostname, or FQDN. 1524 * shortened hostname needs two trailing "\0". 1525 */ 1526 i = 0; 1527 for (p = name; p < name + namelen; p++) { 1528 if (*p && *p == '.') 1529 i++; 1530 } 1531 if (i < 2) 1532 nterm = 2; 1533 else 1534 nterm = 1; 1535 1536 p = name; 1537 while (cp < ep && p < name + namelen) { 1538 i = 0; 1539 for (q = p; q < name + namelen && *q && *q != '.'; q++) 1540 i++; 1541 /* result does not fit into mbuf */ 1542 if (cp + i + 1 >= ep) 1543 goto fail; 1544 /* 1545 * DNS label length restriction, RFC1035 page 8. 1546 * "i == 0" case is included here to avoid returning 1547 * 0-length label on "foo..bar". 1548 */ 1549 if (i <= 0 || i >= 64) 1550 goto fail; 1551 *cp++ = i; 1552 bcopy(p, cp, i); 1553 cp += i; 1554 p = q; 1555 if (p < name + namelen && *p == '.') 1556 p++; 1557 } 1558 /* termination */ 1559 if (cp + nterm >= ep) 1560 goto fail; 1561 while (nterm-- > 0) 1562 *cp++ = '\0'; 1563 m->m_len = cp - mtod(m, char *); 1564 return m; 1565 } 1566 1567 panic("should not reach here"); 1568 /* NOTREACHED */ 1569 1570 fail: 1571 if (m) 1572 m_freem(m); 1573 return NULL; 1574 } 1575 1576 /* 1577 * check if two DNS-encoded string matches. takes care of truncated 1578 * form (with \0\0 at the end). no compression support. 1579 * XXX upper/lowercase match (see RFC2065) 1580 */ 1581 static int 1582 ni6_dnsmatch(const char *a, int alen, const char *b, int blen) 1583 { 1584 const char *a0, *b0; 1585 int l; 1586 1587 /* simplest case - need validation? */ 1588 if (alen == blen && bcmp(a, b, alen) == 0) 1589 return 1; 1590 1591 a0 = a; 1592 b0 = b; 1593 1594 /* termination is mandatory */ 1595 if (alen < 2 || blen < 2) 1596 return 0; 1597 if (a0[alen - 1] != '\0' || b0[blen - 1] != '\0') 1598 return 0; 1599 alen--; 1600 blen--; 1601 1602 while (a - a0 < alen && b - b0 < blen) { 1603 if (a - a0 + 1 > alen || b - b0 + 1 > blen) 1604 return 0; 1605 1606 if ((signed char)a[0] < 0 || (signed char)b[0] < 0) 1607 return 0; 1608 /* we don't support compression yet */ 1609 if (a[0] >= 64 || b[0] >= 64) 1610 return 0; 1611 1612 /* truncated case */ 1613 if (a[0] == 0 && a - a0 == alen - 1) 1614 return 1; 1615 if (b[0] == 0 && b - b0 == blen - 1) 1616 return 1; 1617 if (a[0] == 0 || b[0] == 0) 1618 return 0; 1619 1620 if (a[0] != b[0]) 1621 return 0; 1622 l = a[0]; 1623 if (a - a0 + 1 + l > alen || b - b0 + 1 + l > blen) 1624 return 0; 1625 if (bcmp(a + 1, b + 1, l) != 0) 1626 return 0; 1627 1628 a += 1 + l; 1629 b += 1 + l; 1630 } 1631 1632 if (a - a0 == alen && b - b0 == blen) 1633 return 1; 1634 else 1635 return 0; 1636 } 1637 1638 /* 1639 * calculate the number of addresses to be returned in the node info reply. 1640 */ 1641 static int 1642 ni6_addrs(struct icmp6_nodeinfo *ni6, struct mbuf *m, struct ifnet **ifpp, 1643 char *subj) 1644 { 1645 struct ifnet *ifp; 1646 struct in6_ifaddr *ifa6; 1647 struct ifaddr *ifa; 1648 struct sockaddr_in6 *subj_ip6 = NULL; /* XXX pedant */ 1649 int addrs = 0, addrsofif, iffound = 0; 1650 int niflags = ni6->ni_flags; 1651 1652 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0) { 1653 switch (ni6->ni_code) { 1654 case ICMP6_NI_SUBJ_IPV6: 1655 if (subj == NULL) /* must be impossible... */ 1656 return(0); 1657 subj_ip6 = (struct sockaddr_in6 *)subj; 1658 break; 1659 default: 1660 /* 1661 * XXX: we only support IPv6 subject address for 1662 * this Qtype. 1663 */ 1664 return(0); 1665 } 1666 } 1667 1668 for (ifp = TAILQ_FIRST(&ifnet); ifp; ifp = TAILQ_NEXT(ifp, if_list)) 1669 { 1670 addrsofif = 0; 1671 TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list) 1672 { 1673 if (ifa->ifa_addr->sa_family != AF_INET6) 1674 continue; 1675 ifa6 = (struct in6_ifaddr *)ifa; 1676 1677 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0 && 1678 IN6_ARE_ADDR_EQUAL(&subj_ip6->sin6_addr, 1679 &ifa6->ia_addr.sin6_addr)) 1680 iffound = 1; 1681 1682 /* 1683 * IPv4-mapped addresses can only be returned by a 1684 * Node Information proxy, since they represent 1685 * addresses of IPv4-only nodes, which perforce do 1686 * not implement this protocol. 1687 * [icmp-name-lookups-07, Section 5.4] 1688 * So we don't support NI_NODEADDR_FLAG_COMPAT in 1689 * this function at this moment. 1690 */ 1691 1692 /* What do we have to do about ::1? */ 1693 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1694 case IPV6_ADDR_SCOPE_LINKLOCAL: 1695 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0) 1696 continue; 1697 break; 1698 case IPV6_ADDR_SCOPE_SITELOCAL: 1699 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0) 1700 continue; 1701 break; 1702 case IPV6_ADDR_SCOPE_GLOBAL: 1703 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0) 1704 continue; 1705 break; 1706 default: 1707 continue; 1708 } 1709 1710 /* 1711 * check if anycast is okay. 1712 * XXX: just experimental. not in the spec. 1713 */ 1714 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 && 1715 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0) 1716 continue; /* we need only unicast addresses */ 1717 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 1718 (icmp6_nodeinfo & 4) == 0) { 1719 continue; 1720 } 1721 addrsofif++; /* count the address */ 1722 } 1723 if (iffound) { 1724 *ifpp = ifp; 1725 return(addrsofif); 1726 } 1727 1728 addrs += addrsofif; 1729 } 1730 1731 return(addrs); 1732 } 1733 1734 static int 1735 ni6_store_addrs(struct icmp6_nodeinfo *ni6, struct icmp6_nodeinfo *nni6, 1736 struct ifnet *ifp0, int resid) 1737 { 1738 struct ifnet *ifp = ifp0 ? ifp0 : TAILQ_FIRST(&ifnet); 1739 struct in6_ifaddr *ifa6; 1740 struct ifaddr *ifa; 1741 struct ifnet *ifp_dep = NULL; 1742 int copied = 0, allow_deprecated = 0; 1743 u_char *cp = (u_char *)(nni6 + 1); 1744 int niflags = ni6->ni_flags; 1745 u_int32_t ltime; 1746 1747 if (ifp0 == NULL && !(niflags & NI_NODEADDR_FLAG_ALL)) 1748 return(0); /* needless to copy */ 1749 1750 again: 1751 1752 for (; ifp; ifp = TAILQ_NEXT(ifp, if_list)) 1753 { 1754 TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list) { 1755 if (ifa->ifa_addr->sa_family != AF_INET6) 1756 continue; 1757 ifa6 = (struct in6_ifaddr *)ifa; 1758 1759 if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) != 0 && 1760 allow_deprecated == 0) { 1761 /* 1762 * prefererred address should be put before 1763 * deprecated addresses. 1764 */ 1765 1766 /* record the interface for later search */ 1767 if (ifp_dep == NULL) 1768 ifp_dep = ifp; 1769 1770 continue; 1771 } 1772 else if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) == 0 && 1773 allow_deprecated != 0) 1774 continue; /* we now collect deprecated addrs */ 1775 1776 /* What do we have to do about ::1? */ 1777 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1778 case IPV6_ADDR_SCOPE_LINKLOCAL: 1779 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0) 1780 continue; 1781 break; 1782 case IPV6_ADDR_SCOPE_SITELOCAL: 1783 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0) 1784 continue; 1785 break; 1786 case IPV6_ADDR_SCOPE_GLOBAL: 1787 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0) 1788 continue; 1789 break; 1790 default: 1791 continue; 1792 } 1793 1794 /* 1795 * check if anycast is okay. 1796 * XXX: just experimental. not in the spec. 1797 */ 1798 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 && 1799 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0) 1800 continue; 1801 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 1802 (icmp6_nodeinfo & 4) == 0) { 1803 continue; 1804 } 1805 1806 /* now we can copy the address */ 1807 if (resid < sizeof(struct in6_addr) + 1808 sizeof(u_int32_t)) { 1809 /* 1810 * We give up much more copy. 1811 * Set the truncate flag and return. 1812 */ 1813 nni6->ni_flags |= 1814 NI_NODEADDR_FLAG_TRUNCATE; 1815 return(copied); 1816 } 1817 1818 /* 1819 * Set the TTL of the address. 1820 * The TTL value should be one of the following 1821 * according to the specification: 1822 * 1823 * 1. The remaining lifetime of a DHCP lease on the 1824 * address, or 1825 * 2. The remaining Valid Lifetime of a prefix from 1826 * which the address was derived through Stateless 1827 * Autoconfiguration. 1828 * 1829 * Note that we currently do not support stateful 1830 * address configuration by DHCPv6, so the former 1831 * case can't happen. 1832 */ 1833 if (ifa6->ia6_lifetime.ia6t_expire == 0) 1834 ltime = ND6_INFINITE_LIFETIME; 1835 else { 1836 if (ifa6->ia6_lifetime.ia6t_expire > 1837 time_second) 1838 ltime = htonl(ifa6->ia6_lifetime.ia6t_expire - time_second); 1839 else 1840 ltime = 0; 1841 } 1842 1843 bcopy(<ime, cp, sizeof(u_int32_t)); 1844 cp += sizeof(u_int32_t); 1845 1846 /* copy the address itself */ 1847 bcopy(&ifa6->ia_addr.sin6_addr, cp, 1848 sizeof(struct in6_addr)); 1849 /* XXX: KAME link-local hack; remove ifindex */ 1850 if (IN6_IS_ADDR_LINKLOCAL(&ifa6->ia_addr.sin6_addr)) 1851 ((struct in6_addr *)cp)->s6_addr16[1] = 0; 1852 cp += sizeof(struct in6_addr); 1853 1854 resid -= (sizeof(struct in6_addr) + sizeof(u_int32_t)); 1855 copied += (sizeof(struct in6_addr) + 1856 sizeof(u_int32_t)); 1857 } 1858 if (ifp0) /* we need search only on the specified IF */ 1859 break; 1860 } 1861 1862 if (allow_deprecated == 0 && ifp_dep != NULL) { 1863 ifp = ifp_dep; 1864 allow_deprecated = 1; 1865 1866 goto again; 1867 } 1868 1869 return(copied); 1870 } 1871 1872 /* 1873 * XXX almost dup'ed code with rip6_input. 1874 */ 1875 static int 1876 icmp6_rip6_input(struct mbuf **mp, int off) 1877 { 1878 struct mbuf *m = *mp; 1879 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1880 struct in6pcb *in6p; 1881 struct in6pcb *last = NULL; 1882 struct sockaddr_in6 rip6src; 1883 struct icmp6_hdr *icmp6; 1884 struct mbuf *opts = NULL; 1885 1886 #ifndef PULLDOWN_TEST 1887 /* this is assumed to be safe. */ 1888 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off); 1889 #else 1890 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 1891 if (icmp6 == NULL) { 1892 /* m is already reclaimed */ 1893 return IPPROTO_DONE; 1894 } 1895 #endif 1896 1897 bzero(&rip6src, sizeof(rip6src)); 1898 rip6src.sin6_len = sizeof(struct sockaddr_in6); 1899 rip6src.sin6_family = AF_INET6; 1900 /* KAME hack: recover scopeid */ 1901 (void)in6_recoverscope(&rip6src, &ip6->ip6_src, m->m_pkthdr.rcvif); 1902 1903 LIST_FOREACH(in6p, &ripcbinfo.pcblisthead, inp_list) 1904 { 1905 if (in6p->inp_flags & INP_PLACEMARKER) 1906 continue; 1907 if ((in6p->inp_vflag & INP_IPV6) == 0) 1908 continue; 1909 #ifdef HAVE_NRL_INPCB 1910 if (!(in6p->in6p_flags & INP_IPV6)) 1911 continue; 1912 #endif 1913 if (in6p->in6p_ip6_nxt != IPPROTO_ICMPV6) 1914 continue; 1915 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr) && 1916 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr, &ip6->ip6_dst)) 1917 continue; 1918 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr) && 1919 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr, &ip6->ip6_src)) 1920 continue; 1921 if (in6p->in6p_icmp6filt 1922 && ICMP6_FILTER_WILLBLOCK(icmp6->icmp6_type, 1923 in6p->in6p_icmp6filt)) 1924 continue; 1925 if (last) { 1926 struct mbuf *n; 1927 if ((n = m_copy(m, 0, (int)M_COPYALL)) != NULL) { 1928 if (last->in6p_flags & IN6P_CONTROLOPTS) 1929 ip6_savecontrol(last, &opts, ip6, n); 1930 /* strip intermediate headers */ 1931 m_adj(n, off); 1932 if (sbappendaddr(&last->in6p_socket->so_rcv, 1933 (struct sockaddr *)&rip6src, 1934 n, opts) == 0) { 1935 /* should notify about lost packet */ 1936 m_freem(n); 1937 if (opts) { 1938 m_freem(opts); 1939 } 1940 } else 1941 sorwakeup(last->in6p_socket); 1942 opts = NULL; 1943 } 1944 } 1945 last = in6p; 1946 } 1947 if (last) { 1948 if (last->in6p_flags & IN6P_CONTROLOPTS) 1949 ip6_savecontrol(last, &opts, ip6, m); 1950 /* strip intermediate headers */ 1951 m_adj(m, off); 1952 if (sbappendaddr(&last->in6p_socket->so_rcv, 1953 (struct sockaddr *)&rip6src, m, opts) == 0) { 1954 m_freem(m); 1955 if (opts) 1956 m_freem(opts); 1957 } else 1958 sorwakeup(last->in6p_socket); 1959 } else { 1960 m_freem(m); 1961 ip6stat.ip6s_delivered--; 1962 } 1963 return IPPROTO_DONE; 1964 } 1965 1966 /* 1967 * Reflect the ip6 packet back to the source. 1968 * OFF points to the icmp6 header, counted from the top of the mbuf. 1969 */ 1970 void 1971 icmp6_reflect(struct mbuf *m, size_t off) 1972 { 1973 struct ip6_hdr *ip6; 1974 struct icmp6_hdr *icmp6; 1975 struct in6_ifaddr *ia; 1976 struct in6_addr t, *src = 0; 1977 int plen; 1978 int type, code; 1979 struct ifnet *outif = NULL; 1980 struct sockaddr_in6 sa6_src, sa6_dst; 1981 #ifdef COMPAT_RFC1885 1982 int mtu = IPV6_MMTU; 1983 struct sockaddr_in6 *sin6 = &icmp6_reflect_rt.ro_dst; 1984 #endif 1985 1986 /* too short to reflect */ 1987 if (off < sizeof(struct ip6_hdr)) { 1988 nd6log((LOG_DEBUG, 1989 "sanity fail: off=%lx, sizeof(ip6)=%lx in %s:%d\n", 1990 (u_long)off, (u_long)sizeof(struct ip6_hdr), 1991 __FILE__, __LINE__)); 1992 goto bad; 1993 } 1994 1995 /* 1996 * If there are extra headers between IPv6 and ICMPv6, strip 1997 * off that header first. 1998 */ 1999 #ifdef DIAGNOSTIC 2000 if (sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) > MHLEN) 2001 panic("assumption failed in icmp6_reflect"); 2002 #endif 2003 if (off > sizeof(struct ip6_hdr)) { 2004 size_t l; 2005 struct ip6_hdr nip6; 2006 2007 l = off - sizeof(struct ip6_hdr); 2008 m_copydata(m, 0, sizeof(nip6), (caddr_t)&nip6); 2009 m_adj(m, l); 2010 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 2011 if (m->m_len < l) { 2012 if ((m = m_pullup(m, l)) == NULL) 2013 return; 2014 } 2015 bcopy((caddr_t)&nip6, mtod(m, caddr_t), sizeof(nip6)); 2016 } else /* off == sizeof(struct ip6_hdr) */ { 2017 size_t l; 2018 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 2019 if (m->m_len < l) { 2020 if ((m = m_pullup(m, l)) == NULL) 2021 return; 2022 } 2023 } 2024 plen = m->m_pkthdr.len - sizeof(struct ip6_hdr); 2025 ip6 = mtod(m, struct ip6_hdr *); 2026 ip6->ip6_nxt = IPPROTO_ICMPV6; 2027 icmp6 = (struct icmp6_hdr *)(ip6 + 1); 2028 type = icmp6->icmp6_type; /* keep type for statistics */ 2029 code = icmp6->icmp6_code; /* ditto. */ 2030 2031 t = ip6->ip6_dst; 2032 /* 2033 * ip6_input() drops a packet if its src is multicast. 2034 * So, the src is never multicast. 2035 */ 2036 ip6->ip6_dst = ip6->ip6_src; 2037 2038 /* 2039 * XXX: make sure to embed scope zone information, using 2040 * already embedded IDs or the received interface (if any). 2041 * Note that rcvif may be NULL. 2042 * TODO: scoped routing case (XXX). 2043 */ 2044 bzero(&sa6_src, sizeof(sa6_src)); 2045 sa6_src.sin6_family = AF_INET6; 2046 sa6_src.sin6_len = sizeof(sa6_src); 2047 sa6_src.sin6_addr = ip6->ip6_dst; 2048 in6_recoverscope(&sa6_src, &ip6->ip6_dst, m->m_pkthdr.rcvif); 2049 in6_embedscope(&ip6->ip6_dst, &sa6_src, NULL, NULL); 2050 bzero(&sa6_dst, sizeof(sa6_dst)); 2051 sa6_dst.sin6_family = AF_INET6; 2052 sa6_dst.sin6_len = sizeof(sa6_dst); 2053 sa6_dst.sin6_addr = t; 2054 in6_recoverscope(&sa6_dst, &t, m->m_pkthdr.rcvif); 2055 in6_embedscope(&t, &sa6_dst, NULL, NULL); 2056 2057 #ifdef COMPAT_RFC1885 2058 /* 2059 * xxx guess MTU 2060 * RFC 1885 requires that echo reply should be truncated if it 2061 * does not fit in with (return) path MTU, but the description was 2062 * removed in the new spec. 2063 */ 2064 if (icmp6_reflect_rt.ro_rt == 0 || 2065 ! (IN6_ARE_ADDR_EQUAL(&sin6->sin6_addr, &ip6->ip6_dst))) { 2066 if (icmp6_reflect_rt.ro_rt) { 2067 RTFREE(icmp6_reflect_rt.ro_rt); 2068 icmp6_reflect_rt.ro_rt = 0; 2069 } 2070 bzero(sin6, sizeof(*sin6)); 2071 sin6->sin6_family = PF_INET6; 2072 sin6->sin6_len = sizeof(struct sockaddr_in6); 2073 sin6->sin6_addr = ip6->ip6_dst; 2074 2075 rtalloc_ign((struct route *)&icmp6_reflect_rt.ro_rt, 2076 RTF_PRCLONING); 2077 } 2078 2079 if (icmp6_reflect_rt.ro_rt == 0) 2080 goto bad; 2081 2082 if ((icmp6_reflect_rt.ro_rt->rt_flags & RTF_HOST) 2083 && mtu < icmp6_reflect_rt.ro_rt->rt_ifp->if_mtu) 2084 mtu = icmp6_reflect_rt.ro_rt->rt_rmx.rmx_mtu; 2085 2086 if (mtu < m->m_pkthdr.len) { 2087 plen -= (m->m_pkthdr.len - mtu); 2088 m_adj(m, mtu - m->m_pkthdr.len); 2089 } 2090 #endif 2091 /* 2092 * If the incoming packet was addressed directly to us(i.e. unicast), 2093 * use dst as the src for the reply. 2094 * The IN6_IFF_NOTREADY case would be VERY rare, but is possible 2095 * (for example) when we encounter an error while forwarding procedure 2096 * destined to a duplicated address of ours. 2097 */ 2098 for (ia = in6_ifaddr; ia; ia = ia->ia_next) 2099 if (IN6_ARE_ADDR_EQUAL(&t, &ia->ia_addr.sin6_addr) && 2100 (ia->ia6_flags & (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY)) == 0) { 2101 src = &t; 2102 break; 2103 } 2104 if (ia == NULL && IN6_IS_ADDR_LINKLOCAL(&t) && (m->m_flags & M_LOOP)) { 2105 /* 2106 * This is the case if the dst is our link-local address 2107 * and the sender is also ourselves. 2108 */ 2109 src = &t; 2110 } 2111 2112 if (src == 0) { 2113 int e; 2114 struct route_in6 ro; 2115 2116 /* 2117 * This case matches to multicasts, our anycast, or unicasts 2118 * that we do not own. Select a source address based on the 2119 * source address of the erroneous packet. 2120 */ 2121 bzero(&ro, sizeof(ro)); 2122 src = in6_selectsrc(&sa6_src, NULL, NULL, &ro, NULL, &e); 2123 if (ro.ro_rt) 2124 RTFREE(ro.ro_rt); /* XXX: we could use this */ 2125 if (src == NULL) { 2126 nd6log((LOG_DEBUG, 2127 "icmp6_reflect: source can't be determined: " 2128 "dst=%s, error=%d\n", 2129 ip6_sprintf(&sa6_src.sin6_addr), e)); 2130 goto bad; 2131 } 2132 } 2133 2134 ip6->ip6_src = *src; 2135 2136 ip6->ip6_flow = 0; 2137 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2138 ip6->ip6_vfc |= IPV6_VERSION; 2139 ip6->ip6_nxt = IPPROTO_ICMPV6; 2140 if (m->m_pkthdr.rcvif) { 2141 /* XXX: This may not be the outgoing interface */ 2142 ip6->ip6_hlim = nd_ifinfo[m->m_pkthdr.rcvif->if_index].chlim; 2143 } else 2144 ip6->ip6_hlim = ip6_defhlim; 2145 2146 icmp6->icmp6_cksum = 0; 2147 icmp6->icmp6_cksum = in6_cksum(m, IPPROTO_ICMPV6, 2148 sizeof(struct ip6_hdr), plen); 2149 2150 /* 2151 * XXX option handling 2152 */ 2153 2154 m->m_flags &= ~(M_BCAST|M_MCAST); 2155 2156 #ifdef COMPAT_RFC1885 2157 ip6_output(m, NULL, &icmp6_reflect_rt, 0, NULL, &outif, NULL); 2158 #else 2159 ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL); 2160 #endif 2161 if (outif) 2162 icmp6_ifoutstat_inc(outif, type, code); 2163 2164 return; 2165 2166 bad: 2167 m_freem(m); 2168 return; 2169 } 2170 2171 void 2172 icmp6_fasttimo(void) 2173 { 2174 2175 mld6_fasttimeo(); 2176 } 2177 2178 static const char * 2179 icmp6_redirect_diag(struct in6_addr *src6, struct in6_addr *dst6, 2180 struct in6_addr *tgt6) 2181 { 2182 static char buf[1024]; 2183 snprintf(buf, sizeof(buf), "(src=%s dst=%s tgt=%s)", 2184 ip6_sprintf(src6), ip6_sprintf(dst6), ip6_sprintf(tgt6)); 2185 return buf; 2186 } 2187 2188 void 2189 icmp6_redirect_input(struct mbuf *m, int off) 2190 { 2191 struct ifnet *ifp = m->m_pkthdr.rcvif; 2192 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 2193 struct nd_redirect *nd_rd; 2194 int icmp6len = ntohs(ip6->ip6_plen); 2195 char *lladdr = NULL; 2196 int lladdrlen = 0; 2197 u_char *redirhdr = NULL; 2198 int redirhdrlen = 0; 2199 struct rtentry *rt = NULL; 2200 int is_router; 2201 int is_onlink; 2202 struct in6_addr src6 = ip6->ip6_src; 2203 struct in6_addr redtgt6; 2204 struct in6_addr reddst6; 2205 union nd_opts ndopts; 2206 2207 if (!m || !ifp) 2208 return; 2209 2210 /* XXX if we are router, we don't update route by icmp6 redirect */ 2211 if (ip6_forwarding) 2212 goto freeit; 2213 if (!icmp6_rediraccept) 2214 goto freeit; 2215 2216 #ifndef PULLDOWN_TEST 2217 IP6_EXTHDR_CHECK(m, off, icmp6len,); 2218 nd_rd = (struct nd_redirect *)((caddr_t)ip6 + off); 2219 #else 2220 IP6_EXTHDR_GET(nd_rd, struct nd_redirect *, m, off, icmp6len); 2221 if (nd_rd == NULL) { 2222 icmp6stat.icp6s_tooshort++; 2223 return; 2224 } 2225 #endif 2226 redtgt6 = nd_rd->nd_rd_target; 2227 reddst6 = nd_rd->nd_rd_dst; 2228 2229 if (IN6_IS_ADDR_LINKLOCAL(&redtgt6)) 2230 redtgt6.s6_addr16[1] = htons(ifp->if_index); 2231 if (IN6_IS_ADDR_LINKLOCAL(&reddst6)) 2232 reddst6.s6_addr16[1] = htons(ifp->if_index); 2233 2234 /* validation */ 2235 if (!IN6_IS_ADDR_LINKLOCAL(&src6)) { 2236 nd6log((LOG_ERR, 2237 "ICMP6 redirect sent from %s rejected; " 2238 "must be from linklocal\n", ip6_sprintf(&src6))); 2239 goto bad; 2240 } 2241 if (ip6->ip6_hlim != 255) { 2242 nd6log((LOG_ERR, 2243 "ICMP6 redirect sent from %s rejected; " 2244 "hlim=%d (must be 255)\n", 2245 ip6_sprintf(&src6), ip6->ip6_hlim)); 2246 goto bad; 2247 } 2248 { 2249 /* ip6->ip6_src must be equal to gw for icmp6->icmp6_reddst */ 2250 struct sockaddr_in6 sin6; 2251 struct in6_addr *gw6; 2252 2253 bzero(&sin6, sizeof(sin6)); 2254 sin6.sin6_family = AF_INET6; 2255 sin6.sin6_len = sizeof(struct sockaddr_in6); 2256 bcopy(&reddst6, &sin6.sin6_addr, sizeof reddst6); 2257 rt = rtpurelookup((struct sockaddr *)&sin6); 2258 if (rt != NULL) { 2259 if (rt->rt_gateway == NULL || 2260 rt->rt_gateway->sa_family != AF_INET6) { 2261 nd6log((LOG_ERR, 2262 "ICMP6 redirect rejected; no route " 2263 "with inet6 gateway found for redirect dst: %s\n", 2264 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2265 --rt->rt_refcnt; 2266 goto bad; 2267 } 2268 2269 gw6 = &(((struct sockaddr_in6 *)rt->rt_gateway)->sin6_addr); 2270 if (bcmp(&src6, gw6, sizeof(struct in6_addr)) != 0) { 2271 nd6log((LOG_ERR, 2272 "ICMP6 redirect rejected; " 2273 "not equal to gw-for-src=%s (must be same): " 2274 "%s\n", 2275 ip6_sprintf(gw6), 2276 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2277 --rt->rt_refcnt; 2278 goto bad; 2279 } 2280 } else { 2281 nd6log((LOG_ERR, 2282 "ICMP6 redirect rejected; " 2283 "no route found for redirect dst: %s\n", 2284 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2285 goto bad; 2286 } 2287 --rt->rt_refcnt; 2288 rt = NULL; 2289 } 2290 if (IN6_IS_ADDR_MULTICAST(&reddst6)) { 2291 nd6log((LOG_ERR, 2292 "ICMP6 redirect rejected; " 2293 "redirect dst must be unicast: %s\n", 2294 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2295 goto bad; 2296 } 2297 2298 is_router = is_onlink = 0; 2299 if (IN6_IS_ADDR_LINKLOCAL(&redtgt6)) 2300 is_router = 1; /* router case */ 2301 if (bcmp(&redtgt6, &reddst6, sizeof(redtgt6)) == 0) 2302 is_onlink = 1; /* on-link destination case */ 2303 if (!is_router && !is_onlink) { 2304 nd6log((LOG_ERR, 2305 "ICMP6 redirect rejected; " 2306 "neither router case nor onlink case: %s\n", 2307 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2308 goto bad; 2309 } 2310 /* validation passed */ 2311 2312 icmp6len -= sizeof(*nd_rd); 2313 nd6_option_init(nd_rd + 1, icmp6len, &ndopts); 2314 if (nd6_options(&ndopts) < 0) { 2315 nd6log((LOG_INFO, "icmp6_redirect_input: " 2316 "invalid ND option, rejected: %s\n", 2317 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2318 /* nd6_options have incremented stats */ 2319 goto freeit; 2320 } 2321 2322 if (ndopts.nd_opts_tgt_lladdr) { 2323 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 2324 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 2325 } 2326 2327 if (ndopts.nd_opts_rh) { 2328 redirhdrlen = ndopts.nd_opts_rh->nd_opt_rh_len; 2329 redirhdr = (u_char *)(ndopts.nd_opts_rh + 1); /* xxx */ 2330 } 2331 2332 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 2333 nd6log((LOG_INFO, 2334 "icmp6_redirect_input: lladdrlen mismatch for %s " 2335 "(if %d, icmp6 packet %d): %s\n", 2336 ip6_sprintf(&redtgt6), ifp->if_addrlen, lladdrlen - 2, 2337 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2338 goto bad; 2339 } 2340 2341 /* RFC 2461 8.3 */ 2342 nd6_cache_lladdr(ifp, &redtgt6, lladdr, lladdrlen, ND_REDIRECT, 2343 is_onlink ? ND_REDIRECT_ONLINK : ND_REDIRECT_ROUTER); 2344 2345 if (!is_onlink) { /* better router case. perform rtredirect. */ 2346 /* perform rtredirect */ 2347 struct sockaddr_in6 sdst; 2348 struct sockaddr_in6 sgw; 2349 struct sockaddr_in6 ssrc; 2350 2351 bzero(&sdst, sizeof(sdst)); 2352 bzero(&sgw, sizeof(sgw)); 2353 bzero(&ssrc, sizeof(ssrc)); 2354 sdst.sin6_family = sgw.sin6_family = ssrc.sin6_family = AF_INET6; 2355 sdst.sin6_len = sgw.sin6_len = ssrc.sin6_len = 2356 sizeof(struct sockaddr_in6); 2357 bcopy(&redtgt6, &sgw.sin6_addr, sizeof(struct in6_addr)); 2358 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2359 bcopy(&src6, &ssrc.sin6_addr, sizeof(struct in6_addr)); 2360 rtredirect((struct sockaddr *)&sdst, (struct sockaddr *)&sgw, 2361 (struct sockaddr *)NULL, RTF_GATEWAY | RTF_HOST, 2362 (struct sockaddr *)&ssrc, 2363 (struct rtentry **)NULL); 2364 } 2365 /* finally update cached route in each socket via pfctlinput */ 2366 { 2367 struct sockaddr_in6 sdst; 2368 2369 bzero(&sdst, sizeof(sdst)); 2370 sdst.sin6_family = AF_INET6; 2371 sdst.sin6_len = sizeof(struct sockaddr_in6); 2372 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2373 pfctlinput(PRC_REDIRECT_HOST, (struct sockaddr *)&sdst); 2374 #ifdef IPSEC 2375 key_sa_routechange((struct sockaddr *)&sdst); 2376 #endif 2377 } 2378 2379 freeit: 2380 m_freem(m); 2381 return; 2382 2383 bad: 2384 icmp6stat.icp6s_badredirect++; 2385 m_freem(m); 2386 } 2387 2388 void 2389 icmp6_redirect_output(struct mbuf *m0, struct rtentry *rt) 2390 { 2391 struct ifnet *ifp; /* my outgoing interface */ 2392 struct in6_addr *ifp_ll6; 2393 struct in6_addr *router_ll6; 2394 struct ip6_hdr *sip6; /* m0 as struct ip6_hdr */ 2395 struct mbuf *m = NULL; /* newly allocated one */ 2396 struct ip6_hdr *ip6; /* m as struct ip6_hdr */ 2397 struct nd_redirect *nd_rd; 2398 size_t maxlen; 2399 u_char *p; 2400 struct ifnet *outif = NULL; 2401 struct sockaddr_in6 src_sa; 2402 2403 icmp6_errcount(&icmp6stat.icp6s_outerrhist, ND_REDIRECT, 0); 2404 2405 /* if we are not router, we don't send icmp6 redirect */ 2406 if (!ip6_forwarding || ip6_accept_rtadv) 2407 goto fail; 2408 2409 /* sanity check */ 2410 if (!m0 || !rt || !(rt->rt_flags & RTF_UP) || !(ifp = rt->rt_ifp)) 2411 goto fail; 2412 2413 /* 2414 * Address check: 2415 * the source address must identify a neighbor, and 2416 * the destination address must not be a multicast address 2417 * [RFC 2461, sec 8.2] 2418 */ 2419 sip6 = mtod(m0, struct ip6_hdr *); 2420 bzero(&src_sa, sizeof(src_sa)); 2421 src_sa.sin6_family = AF_INET6; 2422 src_sa.sin6_len = sizeof(src_sa); 2423 src_sa.sin6_addr = sip6->ip6_src; 2424 /* we don't currently use sin6_scope_id, but eventually use it */ 2425 src_sa.sin6_scope_id = in6_addr2scopeid(ifp, &sip6->ip6_src); 2426 if (nd6_is_addr_neighbor(&src_sa, ifp) == 0) 2427 goto fail; 2428 if (IN6_IS_ADDR_MULTICAST(&sip6->ip6_dst)) 2429 goto fail; /* what should we do here? */ 2430 2431 /* rate limit */ 2432 if (icmp6_ratelimit(&sip6->ip6_src, ND_REDIRECT, 0)) 2433 goto fail; 2434 2435 /* 2436 * Since we are going to append up to 1280 bytes (= IPV6_MMTU), 2437 * we almost always ask for an mbuf cluster for simplicity. 2438 * (MHLEN < IPV6_MMTU is almost always true) 2439 */ 2440 #if IPV6_MMTU >= MCLBYTES 2441 # error assumption failed about IPV6_MMTU and MCLBYTES 2442 #endif 2443 MGETHDR(m, MB_DONTWAIT, MT_HEADER); 2444 if (m && IPV6_MMTU >= MHLEN) 2445 MCLGET(m, MB_DONTWAIT); 2446 if (!m) 2447 goto fail; 2448 m->m_pkthdr.rcvif = NULL; 2449 m->m_len = 0; 2450 maxlen = M_TRAILINGSPACE(m); 2451 maxlen = min(IPV6_MMTU, maxlen); 2452 /* just for safety */ 2453 if (maxlen < sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) + 2454 ((sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7)) { 2455 goto fail; 2456 } 2457 2458 { 2459 /* get ip6 linklocal address for ifp(my outgoing interface). */ 2460 struct in6_ifaddr *ia; 2461 if ((ia = in6ifa_ifpforlinklocal(ifp, 2462 IN6_IFF_NOTREADY| 2463 IN6_IFF_ANYCAST)) == NULL) 2464 goto fail; 2465 ifp_ll6 = &ia->ia_addr.sin6_addr; 2466 } 2467 2468 /* get ip6 linklocal address for the router. */ 2469 if (rt->rt_gateway && (rt->rt_flags & RTF_GATEWAY)) { 2470 struct sockaddr_in6 *sin6; 2471 sin6 = (struct sockaddr_in6 *)rt->rt_gateway; 2472 router_ll6 = &sin6->sin6_addr; 2473 if (!IN6_IS_ADDR_LINKLOCAL(router_ll6)) 2474 router_ll6 = (struct in6_addr *)NULL; 2475 } else 2476 router_ll6 = (struct in6_addr *)NULL; 2477 2478 /* ip6 */ 2479 ip6 = mtod(m, struct ip6_hdr *); 2480 ip6->ip6_flow = 0; 2481 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2482 ip6->ip6_vfc |= IPV6_VERSION; 2483 /* ip6->ip6_plen will be set later */ 2484 ip6->ip6_nxt = IPPROTO_ICMPV6; 2485 ip6->ip6_hlim = 255; 2486 /* ip6->ip6_src must be linklocal addr for my outgoing if. */ 2487 bcopy(ifp_ll6, &ip6->ip6_src, sizeof(struct in6_addr)); 2488 bcopy(&sip6->ip6_src, &ip6->ip6_dst, sizeof(struct in6_addr)); 2489 2490 /* ND Redirect */ 2491 nd_rd = (struct nd_redirect *)(ip6 + 1); 2492 nd_rd->nd_rd_type = ND_REDIRECT; 2493 nd_rd->nd_rd_code = 0; 2494 nd_rd->nd_rd_reserved = 0; 2495 if (rt->rt_flags & RTF_GATEWAY) { 2496 /* 2497 * nd_rd->nd_rd_target must be a link-local address in 2498 * better router cases. 2499 */ 2500 if (!router_ll6) 2501 goto fail; 2502 bcopy(router_ll6, &nd_rd->nd_rd_target, 2503 sizeof(nd_rd->nd_rd_target)); 2504 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2505 sizeof(nd_rd->nd_rd_dst)); 2506 } else { 2507 /* make sure redtgt == reddst */ 2508 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_target, 2509 sizeof(nd_rd->nd_rd_target)); 2510 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2511 sizeof(nd_rd->nd_rd_dst)); 2512 } 2513 2514 p = (u_char *)(nd_rd + 1); 2515 2516 if (!router_ll6) 2517 goto nolladdropt; 2518 2519 { 2520 /* target lladdr option */ 2521 struct rtentry *rt_router = NULL; 2522 int len; 2523 struct sockaddr_dl *sdl; 2524 struct nd_opt_hdr *nd_opt; 2525 char *lladdr; 2526 2527 rt_router = nd6_lookup(router_ll6, 0, ifp); 2528 if (!rt_router) 2529 goto nolladdropt; 2530 len = sizeof(*nd_opt) + ifp->if_addrlen; 2531 len = (len + 7) & ~7; /* round by 8 */ 2532 /* safety check */ 2533 if (len + (p - (u_char *)ip6) > maxlen) 2534 goto nolladdropt; 2535 if (!(rt_router->rt_flags & RTF_GATEWAY) && 2536 (rt_router->rt_flags & RTF_LLINFO) && 2537 (rt_router->rt_gateway->sa_family == AF_LINK) && 2538 (sdl = (struct sockaddr_dl *)rt_router->rt_gateway) && 2539 sdl->sdl_alen) { 2540 nd_opt = (struct nd_opt_hdr *)p; 2541 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 2542 nd_opt->nd_opt_len = len >> 3; 2543 lladdr = (char *)(nd_opt + 1); 2544 bcopy(LLADDR(sdl), lladdr, ifp->if_addrlen); 2545 p += len; 2546 } 2547 } 2548 nolladdropt:; 2549 2550 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2551 2552 /* just to be safe */ 2553 #ifdef M_DECRYPTED /*not openbsd*/ 2554 if (m0->m_flags & M_DECRYPTED) 2555 goto noredhdropt; 2556 #endif 2557 if (p - (u_char *)ip6 > maxlen) 2558 goto noredhdropt; 2559 2560 { 2561 /* redirected header option */ 2562 int len; 2563 struct nd_opt_rd_hdr *nd_opt_rh; 2564 2565 /* 2566 * compute the maximum size for icmp6 redirect header option. 2567 * XXX room for auth header? 2568 */ 2569 len = maxlen - (p - (u_char *)ip6); 2570 len &= ~7; 2571 2572 /* This is just for simplicity. */ 2573 if (m0->m_pkthdr.len != m0->m_len) { 2574 if (m0->m_next) { 2575 m_freem(m0->m_next); 2576 m0->m_next = NULL; 2577 } 2578 m0->m_pkthdr.len = m0->m_len; 2579 } 2580 2581 /* 2582 * Redirected header option spec (RFC2461 4.6.3) talks nothing 2583 * about padding/truncate rule for the original IP packet. 2584 * From the discussion on IPv6imp in Feb 1999, the consensus was: 2585 * - "attach as much as possible" is the goal 2586 * - pad if not aligned (original size can be guessed by original 2587 * ip6 header) 2588 * Following code adds the padding if it is simple enough, 2589 * and truncates if not. 2590 */ 2591 if (m0->m_next || m0->m_pkthdr.len != m0->m_len) 2592 panic("assumption failed in %s:%d", __FILE__, __LINE__); 2593 2594 if (len - sizeof(*nd_opt_rh) < m0->m_pkthdr.len) { 2595 /* not enough room, truncate */ 2596 m0->m_pkthdr.len = m0->m_len = len - sizeof(*nd_opt_rh); 2597 } else { 2598 /* enough room, pad or truncate */ 2599 size_t extra; 2600 2601 extra = m0->m_pkthdr.len % 8; 2602 if (extra) { 2603 /* pad if easy enough, truncate if not */ 2604 if (8 - extra <= M_TRAILINGSPACE(m0)) { 2605 /* pad */ 2606 m0->m_len += (8 - extra); 2607 m0->m_pkthdr.len += (8 - extra); 2608 } else { 2609 /* truncate */ 2610 m0->m_pkthdr.len -= extra; 2611 m0->m_len -= extra; 2612 } 2613 } 2614 len = m0->m_pkthdr.len + sizeof(*nd_opt_rh); 2615 m0->m_pkthdr.len = m0->m_len = len - sizeof(*nd_opt_rh); 2616 } 2617 2618 nd_opt_rh = (struct nd_opt_rd_hdr *)p; 2619 bzero(nd_opt_rh, sizeof(*nd_opt_rh)); 2620 nd_opt_rh->nd_opt_rh_type = ND_OPT_REDIRECTED_HEADER; 2621 nd_opt_rh->nd_opt_rh_len = len >> 3; 2622 p += sizeof(*nd_opt_rh); 2623 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2624 2625 /* connect m0 to m */ 2626 m->m_next = m0; 2627 m->m_pkthdr.len = m->m_len + m0->m_len; 2628 } 2629 noredhdropt:; 2630 2631 if (IN6_IS_ADDR_LINKLOCAL(&sip6->ip6_src)) 2632 sip6->ip6_src.s6_addr16[1] = 0; 2633 if (IN6_IS_ADDR_LINKLOCAL(&sip6->ip6_dst)) 2634 sip6->ip6_dst.s6_addr16[1] = 0; 2635 #if 0 2636 if (IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_src)) 2637 ip6->ip6_src.s6_addr16[1] = 0; 2638 if (IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_dst)) 2639 ip6->ip6_dst.s6_addr16[1] = 0; 2640 #endif 2641 if (IN6_IS_ADDR_LINKLOCAL(&nd_rd->nd_rd_target)) 2642 nd_rd->nd_rd_target.s6_addr16[1] = 0; 2643 if (IN6_IS_ADDR_LINKLOCAL(&nd_rd->nd_rd_dst)) 2644 nd_rd->nd_rd_dst.s6_addr16[1] = 0; 2645 2646 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr)); 2647 2648 nd_rd->nd_rd_cksum = 0; 2649 nd_rd->nd_rd_cksum 2650 = in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), ntohs(ip6->ip6_plen)); 2651 2652 /* send the packet to outside... */ 2653 ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL); 2654 if (outif) { 2655 icmp6_ifstat_inc(outif, ifs6_out_msg); 2656 icmp6_ifstat_inc(outif, ifs6_out_redirect); 2657 } 2658 icmp6stat.icp6s_outhist[ND_REDIRECT]++; 2659 2660 return; 2661 2662 fail: 2663 if (m) 2664 m_freem(m); 2665 if (m0) 2666 m_freem(m0); 2667 } 2668 2669 #ifdef HAVE_NRL_INPCB 2670 #define sotoin6pcb sotoinpcb 2671 #define in6pcb inpcb 2672 #define in6p_icmp6filt inp_icmp6filt 2673 #endif 2674 /* 2675 * ICMPv6 socket option processing. 2676 */ 2677 int 2678 icmp6_ctloutput(struct socket *so, struct sockopt *sopt) 2679 { 2680 int error = 0; 2681 int optlen; 2682 struct inpcb *inp = sotoinpcb(so); 2683 int level, op, optname; 2684 2685 if (sopt) { 2686 level = sopt->sopt_level; 2687 op = sopt->sopt_dir; 2688 optname = sopt->sopt_name; 2689 optlen = sopt->sopt_valsize; 2690 } else 2691 level = op = optname = optlen = 0; 2692 2693 if (level != IPPROTO_ICMPV6) { 2694 return EINVAL; 2695 } 2696 2697 switch (op) { 2698 case PRCO_SETOPT: 2699 switch (optname) { 2700 case ICMP6_FILTER: 2701 { 2702 struct icmp6_filter *p; 2703 2704 if (optlen != sizeof(*p)) { 2705 error = EMSGSIZE; 2706 break; 2707 } 2708 if (inp->in6p_icmp6filt == NULL) { 2709 error = EINVAL; 2710 break; 2711 } 2712 error = sooptcopyin(sopt, inp->in6p_icmp6filt, optlen, 2713 optlen); 2714 break; 2715 } 2716 2717 default: 2718 error = ENOPROTOOPT; 2719 break; 2720 } 2721 break; 2722 2723 case PRCO_GETOPT: 2724 switch (optname) { 2725 case ICMP6_FILTER: 2726 { 2727 if (inp->in6p_icmp6filt == NULL) { 2728 error = EINVAL; 2729 break; 2730 } 2731 error = sooptcopyout(sopt, inp->in6p_icmp6filt, 2732 sizeof(struct icmp6_filter)); 2733 break; 2734 } 2735 2736 default: 2737 error = ENOPROTOOPT; 2738 break; 2739 } 2740 break; 2741 } 2742 2743 return(error); 2744 } 2745 #ifdef HAVE_NRL_INPCB 2746 #undef sotoin6pcb 2747 #undef in6pcb 2748 #undef in6p_icmp6filt 2749 #endif 2750 2751 #ifndef HAVE_PPSRATECHECK 2752 #ifndef timersub 2753 #define timersub(tvp, uvp, vvp) \ 2754 do { \ 2755 (vvp)->tv_sec = (tvp)->tv_sec - (uvp)->tv_sec; \ 2756 (vvp)->tv_usec = (tvp)->tv_usec - (uvp)->tv_usec; \ 2757 if ((vvp)->tv_usec < 0) { \ 2758 (vvp)->tv_sec--; \ 2759 (vvp)->tv_usec += 1000000; \ 2760 } \ 2761 } while (0) 2762 #endif 2763 2764 /* 2765 * ppsratecheck(): packets (or events) per second limitation. 2766 */ 2767 static int 2768 ppsratecheck(struct timeval *lasttime, int *curpps, 2769 int maxpps) /* maximum pps allowed */ 2770 { 2771 struct timeval tv, delta; 2772 int rv; 2773 2774 microtime(&tv); 2775 2776 timersub(&tv, lasttime, &delta); 2777 2778 /* 2779 * Check for 0,0 so that the message will be seen at least once. 2780 * If more than one second has passed since the last update of 2781 * lasttime, reset the counter. 2782 * 2783 * We do increment *curpps even in *curpps < maxpps case, as some may 2784 * try to use *curpps for stat purposes as well. 2785 */ 2786 if ((lasttime->tv_sec == 0 && lasttime->tv_usec == 0) || 2787 delta.tv_sec >= 1) { 2788 *lasttime = tv; 2789 *curpps = 0; 2790 rv = 1; 2791 } else if (maxpps < 0) 2792 rv = 1; 2793 else if (*curpps < maxpps) 2794 rv = 1; 2795 else 2796 rv = 0; 2797 2798 #if 1 /* DIAGNOSTIC? */ 2799 /* be careful about wrap-around */ 2800 if (*curpps + 1 > *curpps) 2801 *curpps = *curpps + 1; 2802 #else 2803 /* 2804 * assume that there's not too many calls to this function. 2805 * not sure if the assumption holds, as it depends on *caller's* 2806 * behavior, not the behavior of this function. 2807 * IMHO it is wrong to make assumption on the caller's behavior, 2808 * so the above #if is #if 1, not #ifdef DIAGNOSTIC. 2809 */ 2810 *curpps = *curpps + 1; 2811 #endif 2812 2813 return (rv); 2814 } 2815 #endif 2816 2817 /* 2818 * Perform rate limit check. 2819 * Returns 0 if it is okay to send the icmp6 packet. 2820 * Returns 1 if the router SHOULD NOT send this icmp6 packet due to rate 2821 * limitation. 2822 * 2823 * XXX per-destination/type check necessary? 2824 */ 2825 static int 2826 icmp6_ratelimit(const struct in6_addr *dst, /* not used at this moment */ 2827 const int type, /* not used at this moment */ 2828 const int code) /* not used at this moment */ 2829 { 2830 int ret; 2831 2832 ret = 0; /* okay to send */ 2833 2834 /* PPS limit */ 2835 if (!ppsratecheck(&icmp6errppslim_last, &icmp6errpps_count, 2836 icmp6errppslim)) { 2837 /* The packet is subject to rate limit */ 2838 ret++; 2839 } 2840 2841 return ret; 2842 } 2843