1 /* $FreeBSD$ */ 2 /* $KAME: icmp6.c,v 1.211 2001/04/04 05:56:20 itojun Exp $ */ 3 4 /* 5 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the project nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33 /* 34 * Copyright (c) 1982, 1986, 1988, 1993 35 * The Regents of the University of California. All rights reserved. 36 * 37 * Redistribution and use in source and binary forms, with or without 38 * modification, are permitted provided that the following conditions 39 * are met: 40 * 1. Redistributions of source code must retain the above copyright 41 * notice, this list of conditions and the following disclaimer. 42 * 2. Redistributions in binary form must reproduce the above copyright 43 * notice, this list of conditions and the following disclaimer in the 44 * documentation and/or other materials provided with the distribution. 45 * 3. All advertising materials mentioning features or use of this software 46 * must display the following acknowledgement: 47 * This product includes software developed by the University of 48 * California, Berkeley and its contributors. 49 * 4. Neither the name of the University nor the names of its contributors 50 * may be used to endorse or promote products derived from this software 51 * without specific prior written permission. 52 * 53 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 54 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 55 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 56 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 57 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 58 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 59 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 60 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 61 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 62 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 63 * SUCH DAMAGE. 64 * 65 * @(#)ip_icmp.c 8.2 (Berkeley) 1/4/94 66 */ 67 68 #include "opt_inet.h" 69 #include "opt_inet6.h" 70 #include "opt_ipsec.h" 71 72 #include <sys/param.h> 73 #include <sys/domain.h> 74 #include <sys/kernel.h> 75 #include <sys/lock.h> 76 #include <sys/malloc.h> 77 #include <sys/mbuf.h> 78 #include <sys/protosw.h> 79 #include <sys/signalvar.h> 80 #include <sys/socket.h> 81 #include <sys/socketvar.h> 82 #include <sys/sx.h> 83 #include <sys/syslog.h> 84 #include <sys/systm.h> 85 #include <sys/time.h> 86 87 #include <net/if.h> 88 #include <net/if_dl.h> 89 #include <net/if_types.h> 90 #include <net/route.h> 91 92 #include <netinet/in.h> 93 #include <netinet/in_pcb.h> 94 #include <netinet/in_var.h> 95 #include <netinet/ip6.h> 96 #include <netinet/icmp6.h> 97 #include <netinet6/in6_ifattach.h> 98 #include <netinet6/in6_pcb.h> 99 #include <netinet6/ip6protosw.h> 100 #include <netinet6/ip6_var.h> 101 #include <netinet6/mld6_var.h> 102 #include <netinet6/nd6.h> 103 104 #ifdef IPSEC 105 #include <netinet6/ipsec.h> 106 #include <netkey/key.h> 107 #endif 108 109 #include <net/net_osdep.h> 110 111 #ifdef HAVE_NRL_INPCB 112 /* inpcb members */ 113 #define in6pcb inpcb 114 #define in6p_laddr inp_laddr6 115 #define in6p_faddr inp_faddr6 116 #define in6p_icmp6filt inp_icmp6filt 117 #define in6p_route inp_route 118 #define in6p_socket inp_socket 119 #define in6p_flags inp_flags 120 #define in6p_moptions inp_moptions6 121 #define in6p_outputopts inp_outputopts6 122 #define in6p_ip6 inp_ipv6 123 #define in6p_flowinfo inp_flowinfo 124 #define in6p_sp inp_sp 125 #define in6p_next inp_next 126 #define in6p_prev inp_prev 127 /* macro names */ 128 #define sotoin6pcb sotoinpcb 129 /* function names */ 130 #define in6_pcbdetach in_pcbdetach 131 #define in6_rtchange in_rtchange 132 133 /* 134 * for KAME src sync over BSD*'s. XXX: FreeBSD (>=3) are VERY different from 135 * others... 136 */ 137 #define in6p_ip6_nxt inp_ipv6.ip6_nxt 138 #endif 139 140 extern struct domain inet6domain; 141 142 struct icmp6stat icmp6stat; 143 144 extern struct inpcbhead ripcb; 145 extern int icmp6errppslim; 146 static int icmp6errpps_count = 0; 147 static struct timeval icmp6errppslim_last; 148 extern int icmp6_nodeinfo; 149 150 static void icmp6_errcount __P((struct icmp6errstat *, int, int)); 151 static int icmp6_rip6_input __P((struct mbuf **, int)); 152 static int icmp6_ratelimit __P((const struct in6_addr *, const int, const int)); 153 static const char *icmp6_redirect_diag __P((struct in6_addr *, 154 struct in6_addr *, struct in6_addr *)); 155 #ifndef HAVE_PPSRATECHECK 156 static int ppsratecheck __P((struct timeval *, int *, int)); 157 #endif 158 static struct mbuf *ni6_input __P((struct mbuf *, int)); 159 static struct mbuf *ni6_nametodns __P((const char *, int, int)); 160 static int ni6_dnsmatch __P((const char *, int, const char *, int)); 161 static int ni6_addrs __P((struct icmp6_nodeinfo *, struct mbuf *, 162 struct ifnet **, char *)); 163 static int ni6_store_addrs __P((struct icmp6_nodeinfo *, struct icmp6_nodeinfo *, 164 struct ifnet *, int)); 165 static int icmp6_notify_error __P((struct mbuf *, int, int, int)); 166 167 #ifdef COMPAT_RFC1885 168 static struct route_in6 icmp6_reflect_rt; 169 #endif 170 171 172 void 173 icmp6_init() 174 { 175 mld6_init(); 176 } 177 178 static void 179 icmp6_errcount(stat, type, code) 180 struct icmp6errstat *stat; 181 int type, code; 182 { 183 switch (type) { 184 case ICMP6_DST_UNREACH: 185 switch (code) { 186 case ICMP6_DST_UNREACH_NOROUTE: 187 stat->icp6errs_dst_unreach_noroute++; 188 return; 189 case ICMP6_DST_UNREACH_ADMIN: 190 stat->icp6errs_dst_unreach_admin++; 191 return; 192 case ICMP6_DST_UNREACH_BEYONDSCOPE: 193 stat->icp6errs_dst_unreach_beyondscope++; 194 return; 195 case ICMP6_DST_UNREACH_ADDR: 196 stat->icp6errs_dst_unreach_addr++; 197 return; 198 case ICMP6_DST_UNREACH_NOPORT: 199 stat->icp6errs_dst_unreach_noport++; 200 return; 201 } 202 break; 203 case ICMP6_PACKET_TOO_BIG: 204 stat->icp6errs_packet_too_big++; 205 return; 206 case ICMP6_TIME_EXCEEDED: 207 switch (code) { 208 case ICMP6_TIME_EXCEED_TRANSIT: 209 stat->icp6errs_time_exceed_transit++; 210 return; 211 case ICMP6_TIME_EXCEED_REASSEMBLY: 212 stat->icp6errs_time_exceed_reassembly++; 213 return; 214 } 215 break; 216 case ICMP6_PARAM_PROB: 217 switch (code) { 218 case ICMP6_PARAMPROB_HEADER: 219 stat->icp6errs_paramprob_header++; 220 return; 221 case ICMP6_PARAMPROB_NEXTHEADER: 222 stat->icp6errs_paramprob_nextheader++; 223 return; 224 case ICMP6_PARAMPROB_OPTION: 225 stat->icp6errs_paramprob_option++; 226 return; 227 } 228 break; 229 case ND_REDIRECT: 230 stat->icp6errs_redirect++; 231 return; 232 } 233 stat->icp6errs_unknown++; 234 } 235 236 /* 237 * Generate an error packet of type error in response to bad IP6 packet. 238 */ 239 void 240 icmp6_error(m, type, code, param) 241 struct mbuf *m; 242 int type, code, param; 243 { 244 struct ip6_hdr *oip6, *nip6; 245 struct icmp6_hdr *icmp6; 246 u_int preplen; 247 int off; 248 int nxt; 249 250 icmp6stat.icp6s_error++; 251 252 /* count per-type-code statistics */ 253 icmp6_errcount(&icmp6stat.icp6s_outerrhist, type, code); 254 255 #ifdef M_DECRYPTED /*not openbsd*/ 256 if (m->m_flags & M_DECRYPTED) { 257 icmp6stat.icp6s_canterror++; 258 goto freeit; 259 } 260 #endif 261 262 #ifndef PULLDOWN_TEST 263 IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), ); 264 #else 265 if (m->m_len < sizeof(struct ip6_hdr)) { 266 m = m_pullup(m, sizeof(struct ip6_hdr)); 267 if (m == NULL) 268 return; 269 } 270 #endif 271 oip6 = mtod(m, struct ip6_hdr *); 272 273 /* 274 * Multicast destination check. For unrecognized option errors, 275 * this check has already done in ip6_unknown_opt(), so we can 276 * check only for other errors. 277 */ 278 if ((m->m_flags & (M_BCAST|M_MCAST) || 279 IN6_IS_ADDR_MULTICAST(&oip6->ip6_dst)) && 280 (type != ICMP6_PACKET_TOO_BIG && 281 (type != ICMP6_PARAM_PROB || 282 code != ICMP6_PARAMPROB_OPTION))) 283 goto freeit; 284 285 /* Source address check. XXX: the case of anycast source? */ 286 if (IN6_IS_ADDR_UNSPECIFIED(&oip6->ip6_src) || 287 IN6_IS_ADDR_MULTICAST(&oip6->ip6_src)) 288 goto freeit; 289 290 /* 291 * If we are about to send ICMPv6 against ICMPv6 error/redirect, 292 * don't do it. 293 */ 294 nxt = -1; 295 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); 296 if (off >= 0 && nxt == IPPROTO_ICMPV6) { 297 struct icmp6_hdr *icp; 298 299 #ifndef PULLDOWN_TEST 300 IP6_EXTHDR_CHECK(m, 0, off + sizeof(struct icmp6_hdr), ); 301 icp = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 302 #else 303 IP6_EXTHDR_GET(icp, struct icmp6_hdr *, m, off, 304 sizeof(*icp)); 305 if (icp == NULL) { 306 icmp6stat.icp6s_tooshort++; 307 return; 308 } 309 #endif 310 if (icp->icmp6_type < ICMP6_ECHO_REQUEST || 311 icp->icmp6_type == ND_REDIRECT) { 312 /* 313 * ICMPv6 error 314 * Special case: for redirect (which is 315 * informational) we must not send icmp6 error. 316 */ 317 icmp6stat.icp6s_canterror++; 318 goto freeit; 319 } else { 320 /* ICMPv6 informational - send the error */ 321 } 322 } else { 323 /* non-ICMPv6 - send the error */ 324 } 325 326 oip6 = mtod(m, struct ip6_hdr *); /* adjust pointer */ 327 328 /* Finally, do rate limitation check. */ 329 if (icmp6_ratelimit(&oip6->ip6_src, type, code)) { 330 icmp6stat.icp6s_toofreq++; 331 goto freeit; 332 } 333 334 /* 335 * OK, ICMP6 can be generated. 336 */ 337 338 if (m->m_pkthdr.len >= ICMPV6_PLD_MAXLEN) 339 m_adj(m, ICMPV6_PLD_MAXLEN - m->m_pkthdr.len); 340 341 preplen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 342 M_PREPEND(m, preplen, M_DONTWAIT); 343 if (m && m->m_len < preplen) 344 m = m_pullup(m, preplen); 345 if (m == NULL) { 346 nd6log((LOG_DEBUG, "ENOBUFS in icmp6_error %d\n", __LINE__)); 347 return; 348 } 349 350 nip6 = mtod(m, struct ip6_hdr *); 351 nip6->ip6_src = oip6->ip6_src; 352 nip6->ip6_dst = oip6->ip6_dst; 353 354 if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_src)) 355 oip6->ip6_src.s6_addr16[1] = 0; 356 if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_dst)) 357 oip6->ip6_dst.s6_addr16[1] = 0; 358 359 icmp6 = (struct icmp6_hdr *)(nip6 + 1); 360 icmp6->icmp6_type = type; 361 icmp6->icmp6_code = code; 362 icmp6->icmp6_pptr = htonl((u_int32_t)param); 363 364 /* 365 * icmp6_reflect() is designed to be in the input path. 366 * icmp6_error() can be called from both input and outut path, 367 * and if we are in output path rcvif could contain bogus value. 368 * clear m->m_pkthdr.rcvif for safety, we should have enough scope 369 * information in ip header (nip6). 370 */ 371 m->m_pkthdr.rcvif = NULL; 372 373 icmp6stat.icp6s_outhist[type]++; 374 icmp6_reflect(m, sizeof(struct ip6_hdr)); /* header order: IPv6 - ICMPv6 */ 375 376 return; 377 378 freeit: 379 /* 380 * If we can't tell wheter or not we can generate ICMP6, free it. 381 */ 382 m_freem(m); 383 } 384 385 /* 386 * Process a received ICMP6 message. 387 */ 388 int 389 icmp6_input(mp, offp, proto) 390 struct mbuf **mp; 391 int *offp, proto; 392 { 393 struct mbuf *m = *mp, *n; 394 struct ip6_hdr *ip6, *nip6; 395 struct icmp6_hdr *icmp6, *nicmp6; 396 int off = *offp; 397 int icmp6len = m->m_pkthdr.len - *offp; 398 int code, sum, noff; 399 400 #ifndef PULLDOWN_TEST 401 IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_hdr), IPPROTO_DONE); 402 /* m might change if M_LOOP. So, call mtod after this */ 403 #endif 404 405 /* 406 * Locate icmp6 structure in mbuf, and check 407 * that not corrupted and of at least minimum length 408 */ 409 410 ip6 = mtod(m, struct ip6_hdr *); 411 if (icmp6len < sizeof(struct icmp6_hdr)) { 412 icmp6stat.icp6s_tooshort++; 413 goto freeit; 414 } 415 416 /* 417 * calculate the checksum 418 */ 419 #ifndef PULLDOWN_TEST 420 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off); 421 #else 422 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 423 if (icmp6 == NULL) { 424 icmp6stat.icp6s_tooshort++; 425 return IPPROTO_DONE; 426 } 427 #endif 428 code = icmp6->icmp6_code; 429 430 if ((sum = in6_cksum(m, IPPROTO_ICMPV6, off, icmp6len)) != 0) { 431 nd6log((LOG_ERR, 432 "ICMP6 checksum error(%d|%x) %s\n", 433 icmp6->icmp6_type, sum, ip6_sprintf(&ip6->ip6_src))); 434 icmp6stat.icp6s_checksum++; 435 goto freeit; 436 } 437 438 if (faithprefix_p != NULL && (*faithprefix_p)(&ip6->ip6_dst)) { 439 /* 440 * Deliver very specific ICMP6 type only. 441 * This is important to deilver TOOBIG. Otherwise PMTUD 442 * will not work. 443 */ 444 switch (icmp6->icmp6_type) { 445 case ICMP6_DST_UNREACH: 446 case ICMP6_PACKET_TOO_BIG: 447 case ICMP6_TIME_EXCEEDED: 448 break; 449 default: 450 goto freeit; 451 } 452 } 453 454 icmp6stat.icp6s_inhist[icmp6->icmp6_type]++; 455 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_msg); 456 if (icmp6->icmp6_type < ICMP6_INFOMSG_MASK) 457 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_error); 458 459 switch (icmp6->icmp6_type) { 460 case ICMP6_DST_UNREACH: 461 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_dstunreach); 462 switch (code) { 463 case ICMP6_DST_UNREACH_NOROUTE: 464 code = PRC_UNREACH_NET; 465 break; 466 case ICMP6_DST_UNREACH_ADMIN: 467 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_adminprohib); 468 code = PRC_UNREACH_PROTOCOL; /* is this a good code? */ 469 break; 470 case ICMP6_DST_UNREACH_ADDR: 471 code = PRC_HOSTDEAD; 472 break; 473 #ifdef COMPAT_RFC1885 474 case ICMP6_DST_UNREACH_NOTNEIGHBOR: 475 code = PRC_UNREACH_SRCFAIL; 476 break; 477 #else 478 case ICMP6_DST_UNREACH_BEYONDSCOPE: 479 /* I mean "source address was incorrect." */ 480 code = PRC_PARAMPROB; 481 break; 482 #endif 483 case ICMP6_DST_UNREACH_NOPORT: 484 code = PRC_UNREACH_PORT; 485 break; 486 default: 487 goto badcode; 488 } 489 goto deliver; 490 break; 491 492 case ICMP6_PACKET_TOO_BIG: 493 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_pkttoobig); 494 if (code != 0) 495 goto badcode; 496 497 code = PRC_MSGSIZE; 498 499 /* 500 * Updating the path MTU will be done after examining 501 * intermediate extension headers. 502 */ 503 goto deliver; 504 break; 505 506 case ICMP6_TIME_EXCEEDED: 507 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_timeexceed); 508 switch (code) { 509 case ICMP6_TIME_EXCEED_TRANSIT: 510 case ICMP6_TIME_EXCEED_REASSEMBLY: 511 code += PRC_TIMXCEED_INTRANS; 512 break; 513 default: 514 goto badcode; 515 } 516 goto deliver; 517 break; 518 519 case ICMP6_PARAM_PROB: 520 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_paramprob); 521 switch (code) { 522 case ICMP6_PARAMPROB_NEXTHEADER: 523 code = PRC_UNREACH_PROTOCOL; 524 break; 525 case ICMP6_PARAMPROB_HEADER: 526 case ICMP6_PARAMPROB_OPTION: 527 code = PRC_PARAMPROB; 528 break; 529 default: 530 goto badcode; 531 } 532 goto deliver; 533 break; 534 535 case ICMP6_ECHO_REQUEST: 536 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echo); 537 if (code != 0) 538 goto badcode; 539 if ((n = m_copy(m, 0, M_COPYALL)) == NULL) { 540 /* Give up remote */ 541 break; 542 } 543 if ((n->m_flags & M_EXT) != 0 544 || n->m_len < off + sizeof(struct icmp6_hdr)) { 545 struct mbuf *n0 = n; 546 const int maxlen = sizeof(*nip6) + sizeof(*nicmp6); 547 548 /* 549 * Prepare an internal mbuf. m_pullup() doesn't 550 * always copy the length we specified. 551 */ 552 if (maxlen >= MCLBYTES) { 553 /* Give up remote */ 554 m_freem(n0); 555 break; 556 } 557 MGETHDR(n, M_DONTWAIT, n0->m_type); 558 if (n && maxlen >= MHLEN) { 559 MCLGET(n, M_DONTWAIT); 560 if ((n->m_flags & M_EXT) == 0) { 561 m_free(n); 562 n = NULL; 563 } 564 } 565 if (n == NULL) { 566 /* Give up remote */ 567 m_freem(n0); 568 break; 569 } 570 M_COPY_PKTHDR(n, n0); 571 /* 572 * Copy IPv6 and ICMPv6 only. 573 */ 574 nip6 = mtod(n, struct ip6_hdr *); 575 bcopy(ip6, nip6, sizeof(struct ip6_hdr)); 576 nicmp6 = (struct icmp6_hdr *)(nip6 + 1); 577 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr)); 578 noff = sizeof(struct ip6_hdr); 579 n->m_pkthdr.len = n->m_len = 580 noff + sizeof(struct icmp6_hdr); 581 /* 582 * Adjust mbuf. ip6_plen will be adjusted in 583 * ip6_output(). 584 */ 585 m_adj(n0, off + sizeof(struct icmp6_hdr)); 586 n->m_pkthdr.len += n0->m_pkthdr.len; 587 n->m_next = n0; 588 n0->m_flags &= ~M_PKTHDR; 589 } else { 590 nip6 = mtod(n, struct ip6_hdr *); 591 nicmp6 = (struct icmp6_hdr *)((caddr_t)nip6 + off); 592 noff = off; 593 } 594 nicmp6->icmp6_type = ICMP6_ECHO_REPLY; 595 nicmp6->icmp6_code = 0; 596 if (n) { 597 icmp6stat.icp6s_reflect++; 598 icmp6stat.icp6s_outhist[ICMP6_ECHO_REPLY]++; 599 icmp6_reflect(n, noff); 600 } 601 break; 602 603 case ICMP6_ECHO_REPLY: 604 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echoreply); 605 if (code != 0) 606 goto badcode; 607 break; 608 609 case MLD_LISTENER_QUERY: 610 case MLD_LISTENER_REPORT: 611 if (icmp6len < sizeof(struct mld_hdr)) 612 goto badlen; 613 if (icmp6->icmp6_type == MLD_LISTENER_QUERY) /* XXX: ugly... */ 614 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldquery); 615 else 616 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldreport); 617 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 618 /* give up local */ 619 mld6_input(m, off); 620 m = NULL; 621 goto freeit; 622 } 623 mld6_input(n, off); 624 /* m stays. */ 625 break; 626 627 case MLD_LISTENER_DONE: 628 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mlddone); 629 if (icmp6len < sizeof(struct mld_hdr)) /* necessary? */ 630 goto badlen; 631 break; /* nothing to be done in kernel */ 632 633 case MLD_MTRACE_RESP: 634 case MLD_MTRACE: 635 /* XXX: these two are experimental. not officially defind. */ 636 /* XXX: per-interface statistics? */ 637 break; /* just pass it to applications */ 638 639 case ICMP6_WRUREQUEST: /* ICMP6_FQDN_QUERY */ 640 { 641 enum { WRU, FQDN } mode; 642 643 if (!icmp6_nodeinfo) 644 break; 645 646 if (icmp6len == sizeof(struct icmp6_hdr) + 4) 647 mode = WRU; 648 else if (icmp6len >= sizeof(struct icmp6_nodeinfo)) 649 mode = FQDN; 650 else 651 goto badlen; 652 653 #define hostnamelen strlen(hostname) 654 if (mode == FQDN) { 655 #ifndef PULLDOWN_TEST 656 IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_nodeinfo), 657 IPPROTO_DONE); 658 #endif 659 n = m_copy(m, 0, M_COPYALL); 660 if (n) 661 n = ni6_input(n, off); 662 /* XXX meaningless if n == NULL */ 663 noff = sizeof(struct ip6_hdr); 664 } else { 665 u_char *p; 666 int maxlen, maxhlen; 667 668 if ((icmp6_nodeinfo & 5) != 5) 669 break; 670 671 if (code != 0) 672 goto badcode; 673 maxlen = sizeof(*nip6) + sizeof(*nicmp6) + 4; 674 if (maxlen >= MCLBYTES) { 675 /* Give up remote */ 676 break; 677 } 678 MGETHDR(n, M_DONTWAIT, m->m_type); 679 if (n && maxlen > MHLEN) { 680 MCLGET(n, M_DONTWAIT); 681 if ((n->m_flags & M_EXT) == 0) { 682 m_free(n); 683 n = NULL; 684 } 685 } 686 if (n == NULL) { 687 /* Give up remote */ 688 break; 689 } 690 n->m_pkthdr.rcvif = NULL; 691 n->m_len = 0; 692 maxhlen = M_TRAILINGSPACE(n) - maxlen; 693 if (maxhlen > hostnamelen) 694 maxhlen = hostnamelen; 695 /* 696 * Copy IPv6 and ICMPv6 only. 697 */ 698 nip6 = mtod(n, struct ip6_hdr *); 699 bcopy(ip6, nip6, sizeof(struct ip6_hdr)); 700 nicmp6 = (struct icmp6_hdr *)(nip6 + 1); 701 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr)); 702 p = (u_char *)(nicmp6 + 1); 703 bzero(p, 4); 704 bcopy(hostname, p + 4, maxhlen); /* meaningless TTL */ 705 noff = sizeof(struct ip6_hdr); 706 M_COPY_PKTHDR(n, m); /* just for rcvif */ 707 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) + 708 sizeof(struct icmp6_hdr) + 4 + maxhlen; 709 nicmp6->icmp6_type = ICMP6_WRUREPLY; 710 nicmp6->icmp6_code = 0; 711 } 712 #undef hostnamelen 713 if (n) { 714 icmp6stat.icp6s_reflect++; 715 icmp6stat.icp6s_outhist[ICMP6_WRUREPLY]++; 716 icmp6_reflect(n, noff); 717 } 718 break; 719 } 720 721 case ICMP6_WRUREPLY: 722 if (code != 0) 723 goto badcode; 724 break; 725 726 case ND_ROUTER_SOLICIT: 727 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routersolicit); 728 if (code != 0) 729 goto badcode; 730 if (icmp6len < sizeof(struct nd_router_solicit)) 731 goto badlen; 732 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 733 /* give up local */ 734 nd6_rs_input(m, off, icmp6len); 735 m = NULL; 736 goto freeit; 737 } 738 nd6_rs_input(n, off, icmp6len); 739 /* m stays. */ 740 break; 741 742 case ND_ROUTER_ADVERT: 743 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routeradvert); 744 if (code != 0) 745 goto badcode; 746 if (icmp6len < sizeof(struct nd_router_advert)) 747 goto badlen; 748 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 749 /* give up local */ 750 nd6_ra_input(m, off, icmp6len); 751 m = NULL; 752 goto freeit; 753 } 754 nd6_ra_input(n, off, icmp6len); 755 /* m stays. */ 756 break; 757 758 case ND_NEIGHBOR_SOLICIT: 759 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighborsolicit); 760 if (code != 0) 761 goto badcode; 762 if (icmp6len < sizeof(struct nd_neighbor_solicit)) 763 goto badlen; 764 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 765 /* give up local */ 766 nd6_ns_input(m, off, icmp6len); 767 m = NULL; 768 goto freeit; 769 } 770 nd6_ns_input(n, off, icmp6len); 771 /* m stays. */ 772 break; 773 774 case ND_NEIGHBOR_ADVERT: 775 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighboradvert); 776 if (code != 0) 777 goto badcode; 778 if (icmp6len < sizeof(struct nd_neighbor_advert)) 779 goto badlen; 780 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 781 /* give up local */ 782 nd6_na_input(m, off, icmp6len); 783 m = NULL; 784 goto freeit; 785 } 786 nd6_na_input(n, off, icmp6len); 787 /* m stays. */ 788 break; 789 790 case ND_REDIRECT: 791 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_redirect); 792 if (code != 0) 793 goto badcode; 794 if (icmp6len < sizeof(struct nd_redirect)) 795 goto badlen; 796 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 797 /* give up local */ 798 icmp6_redirect_input(m, off); 799 m = NULL; 800 goto freeit; 801 } 802 icmp6_redirect_input(n, off); 803 /* m stays. */ 804 break; 805 806 case ICMP6_ROUTER_RENUMBERING: 807 if (code != ICMP6_ROUTER_RENUMBERING_COMMAND && 808 code != ICMP6_ROUTER_RENUMBERING_RESULT) 809 goto badcode; 810 if (icmp6len < sizeof(struct icmp6_router_renum)) 811 goto badlen; 812 break; 813 814 default: 815 nd6log((LOG_DEBUG, 816 "icmp6_input: unknown type %d(src=%s, dst=%s, ifid=%d)\n", 817 icmp6->icmp6_type, ip6_sprintf(&ip6->ip6_src), 818 ip6_sprintf(&ip6->ip6_dst), 819 m->m_pkthdr.rcvif ? m->m_pkthdr.rcvif->if_index : 0)); 820 if (icmp6->icmp6_type < ICMP6_ECHO_REQUEST) { 821 /* ICMPv6 error: MUST deliver it by spec... */ 822 code = PRC_NCMDS; 823 /* deliver */ 824 } else { 825 /* ICMPv6 informational: MUST not deliver */ 826 break; 827 } 828 deliver: 829 if (icmp6_notify_error(m, off, icmp6len, code)) { 830 /* In this case, m should've been freed. */ 831 return(IPPROTO_DONE); 832 } 833 break; 834 835 badcode: 836 icmp6stat.icp6s_badcode++; 837 break; 838 839 badlen: 840 icmp6stat.icp6s_badlen++; 841 break; 842 } 843 844 /* deliver the packet to appropriate sockets */ 845 icmp6_rip6_input(&m, *offp); 846 847 return IPPROTO_DONE; 848 849 freeit: 850 m_freem(m); 851 return IPPROTO_DONE; 852 } 853 854 static int 855 icmp6_notify_error(m, off, icmp6len, code) 856 struct mbuf *m; 857 int off, icmp6len; 858 { 859 struct icmp6_hdr *icmp6; 860 struct ip6_hdr *eip6; 861 u_int32_t notifymtu; 862 struct sockaddr_in6 icmp6src, icmp6dst; 863 864 if (icmp6len < sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr)) { 865 icmp6stat.icp6s_tooshort++; 866 goto freeit; 867 } 868 #ifndef PULLDOWN_TEST 869 IP6_EXTHDR_CHECK(m, off, 870 sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr), 871 -1); 872 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 873 #else 874 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, 875 sizeof(*icmp6) + sizeof(struct ip6_hdr)); 876 if (icmp6 == NULL) { 877 icmp6stat.icp6s_tooshort++; 878 return(-1); 879 } 880 #endif 881 eip6 = (struct ip6_hdr *)(icmp6 + 1); 882 883 /* Detect the upper level protocol */ 884 { 885 void (*ctlfunc) __P((int, struct sockaddr *, void *)); 886 u_int8_t nxt = eip6->ip6_nxt; 887 int eoff = off + sizeof(struct icmp6_hdr) + 888 sizeof(struct ip6_hdr); 889 struct ip6ctlparam ip6cp; 890 struct in6_addr *finaldst = NULL; 891 int icmp6type = icmp6->icmp6_type; 892 struct ip6_frag *fh; 893 struct ip6_rthdr *rth; 894 struct ip6_rthdr0 *rth0; 895 int rthlen; 896 897 while (1) { /* XXX: should avoid infinite loop explicitly? */ 898 struct ip6_ext *eh; 899 900 switch (nxt) { 901 case IPPROTO_HOPOPTS: 902 case IPPROTO_DSTOPTS: 903 case IPPROTO_AH: 904 #ifndef PULLDOWN_TEST 905 IP6_EXTHDR_CHECK(m, 0, eoff + 906 sizeof(struct ip6_ext), 907 -1); 908 eh = (struct ip6_ext *)(mtod(m, caddr_t) 909 + eoff); 910 #else 911 IP6_EXTHDR_GET(eh, struct ip6_ext *, m, 912 eoff, sizeof(*eh)); 913 if (eh == NULL) { 914 icmp6stat.icp6s_tooshort++; 915 return(-1); 916 } 917 #endif 918 919 if (nxt == IPPROTO_AH) 920 eoff += (eh->ip6e_len + 2) << 2; 921 else 922 eoff += (eh->ip6e_len + 1) << 3; 923 nxt = eh->ip6e_nxt; 924 break; 925 case IPPROTO_ROUTING: 926 /* 927 * When the erroneous packet contains a 928 * routing header, we should examine the 929 * header to determine the final destination. 930 * Otherwise, we can't properly update 931 * information that depends on the final 932 * destination (e.g. path MTU). 933 */ 934 #ifndef PULLDOWN_TEST 935 IP6_EXTHDR_CHECK(m, 0, eoff + sizeof(*rth), 936 -1); 937 rth = (struct ip6_rthdr *)(mtod(m, caddr_t) 938 + eoff); 939 #else 940 IP6_EXTHDR_GET(rth, struct ip6_rthdr *, m, 941 eoff, sizeof(*rth)); 942 if (rth == NULL) { 943 icmp6stat.icp6s_tooshort++; 944 return(-1); 945 } 946 #endif 947 rthlen = (rth->ip6r_len + 1) << 3; 948 /* 949 * XXX: currently there is no 950 * officially defined type other 951 * than type-0. 952 * Note that if the segment left field 953 * is 0, all intermediate hops must 954 * have been passed. 955 */ 956 if (rth->ip6r_segleft && 957 rth->ip6r_type == IPV6_RTHDR_TYPE_0) { 958 int hops; 959 960 #ifndef PULLDOWN_TEST 961 IP6_EXTHDR_CHECK(m, 0, eoff + rthlen, 962 -1); 963 rth0 = (struct ip6_rthdr0 *)(mtod(m, caddr_t) + eoff); 964 #else 965 IP6_EXTHDR_GET(rth0, 966 struct ip6_rthdr0 *, m, 967 eoff, rthlen); 968 if (rth0 == NULL) { 969 icmp6stat.icp6s_tooshort++; 970 return(-1); 971 } 972 #endif 973 /* just ignore a bogus header */ 974 if ((rth0->ip6r0_len % 2) == 0 && 975 (hops = rth0->ip6r0_len/2)) 976 finaldst = (struct in6_addr *)(rth0 + 1) + (hops - 1); 977 } 978 eoff += rthlen; 979 nxt = rth->ip6r_nxt; 980 break; 981 case IPPROTO_FRAGMENT: 982 #ifndef PULLDOWN_TEST 983 IP6_EXTHDR_CHECK(m, 0, eoff + 984 sizeof(struct ip6_frag), 985 -1); 986 fh = (struct ip6_frag *)(mtod(m, caddr_t) 987 + eoff); 988 #else 989 IP6_EXTHDR_GET(fh, struct ip6_frag *, m, 990 eoff, sizeof(*fh)); 991 if (fh == NULL) { 992 icmp6stat.icp6s_tooshort++; 993 return(-1); 994 } 995 #endif 996 /* 997 * Data after a fragment header is meaningless 998 * unless it is the first fragment, but 999 * we'll go to the notify label for path MTU 1000 * discovery. 1001 */ 1002 if (fh->ip6f_offlg & IP6F_OFF_MASK) 1003 goto notify; 1004 1005 eoff += sizeof(struct ip6_frag); 1006 nxt = fh->ip6f_nxt; 1007 break; 1008 default: 1009 /* 1010 * This case includes ESP and the No Next 1011 * Header. In such cases going to the notify 1012 * label does not have any meaning 1013 * (i.e. ctlfunc will be NULL), but we go 1014 * anyway since we might have to update 1015 * path MTU information. 1016 */ 1017 goto notify; 1018 } 1019 } 1020 notify: 1021 #ifndef PULLDOWN_TEST 1022 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 1023 #else 1024 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, 1025 sizeof(*icmp6) + sizeof(struct ip6_hdr)); 1026 if (icmp6 == NULL) { 1027 icmp6stat.icp6s_tooshort++; 1028 return(-1); 1029 } 1030 #endif 1031 1032 eip6 = (struct ip6_hdr *)(icmp6 + 1); 1033 bzero(&icmp6dst, sizeof(icmp6dst)); 1034 icmp6dst.sin6_len = sizeof(struct sockaddr_in6); 1035 icmp6dst.sin6_family = AF_INET6; 1036 if (finaldst == NULL) 1037 icmp6dst.sin6_addr = eip6->ip6_dst; 1038 else 1039 icmp6dst.sin6_addr = *finaldst; 1040 icmp6dst.sin6_scope_id = in6_addr2scopeid(m->m_pkthdr.rcvif, 1041 &icmp6dst.sin6_addr); 1042 #ifndef SCOPEDROUTING 1043 if (in6_embedscope(&icmp6dst.sin6_addr, &icmp6dst, 1044 NULL, NULL)) { 1045 /* should be impossbile */ 1046 nd6log((LOG_DEBUG, 1047 "icmp6_notify_error: in6_embedscope failed\n")); 1048 goto freeit; 1049 } 1050 #endif 1051 1052 /* 1053 * retrieve parameters from the inner IPv6 header, and convert 1054 * them into sockaddr structures. 1055 */ 1056 bzero(&icmp6src, sizeof(icmp6src)); 1057 icmp6src.sin6_len = sizeof(struct sockaddr_in6); 1058 icmp6src.sin6_family = AF_INET6; 1059 icmp6src.sin6_addr = eip6->ip6_src; 1060 icmp6src.sin6_scope_id = in6_addr2scopeid(m->m_pkthdr.rcvif, 1061 &icmp6src.sin6_addr); 1062 #ifndef SCOPEDROUTING 1063 if (in6_embedscope(&icmp6src.sin6_addr, &icmp6src, 1064 NULL, NULL)) { 1065 /* should be impossbile */ 1066 nd6log((LOG_DEBUG, 1067 "icmp6_notify_error: in6_embedscope failed\n")); 1068 goto freeit; 1069 } 1070 #endif 1071 icmp6src.sin6_flowinfo = 1072 (eip6->ip6_flow & IPV6_FLOWLABEL_MASK); 1073 1074 if (finaldst == NULL) 1075 finaldst = &eip6->ip6_dst; 1076 ip6cp.ip6c_m = m; 1077 ip6cp.ip6c_icmp6 = icmp6; 1078 ip6cp.ip6c_ip6 = (struct ip6_hdr *)(icmp6 + 1); 1079 ip6cp.ip6c_off = eoff; 1080 ip6cp.ip6c_finaldst = finaldst; 1081 ip6cp.ip6c_src = &icmp6src; 1082 ip6cp.ip6c_nxt = nxt; 1083 1084 if (icmp6type == ICMP6_PACKET_TOO_BIG) { 1085 notifymtu = ntohl(icmp6->icmp6_mtu); 1086 ip6cp.ip6c_cmdarg = (void *)¬ifymtu; 1087 icmp6_mtudisc_update(&ip6cp, 1); /*XXX*/ 1088 } 1089 1090 ctlfunc = (void (*) __P((int, struct sockaddr *, void *))) 1091 (inet6sw[ip6_protox[nxt]].pr_ctlinput); 1092 if (ctlfunc) { 1093 (void) (*ctlfunc)(code, (struct sockaddr *)&icmp6dst, 1094 &ip6cp); 1095 } 1096 } 1097 return(0); 1098 1099 freeit: 1100 m_freem(m); 1101 return(-1); 1102 } 1103 1104 void 1105 icmp6_mtudisc_update(ip6cp, validated) 1106 struct ip6ctlparam *ip6cp; 1107 int validated; 1108 { 1109 struct in6_addr *dst = ip6cp->ip6c_finaldst; 1110 struct icmp6_hdr *icmp6 = ip6cp->ip6c_icmp6; 1111 struct mbuf *m = ip6cp->ip6c_m; /* will be necessary for scope issue */ 1112 u_int mtu = ntohl(icmp6->icmp6_mtu); 1113 struct rtentry *rt = NULL; 1114 struct sockaddr_in6 sin6; 1115 1116 if (!validated) 1117 return; 1118 1119 bzero(&sin6, sizeof(sin6)); 1120 sin6.sin6_family = PF_INET6; 1121 sin6.sin6_len = sizeof(struct sockaddr_in6); 1122 sin6.sin6_addr = *dst; 1123 /* XXX normally, this won't happen */ 1124 if (IN6_IS_ADDR_LINKLOCAL(dst)) { 1125 sin6.sin6_addr.s6_addr16[1] = 1126 htons(m->m_pkthdr.rcvif->if_index); 1127 } 1128 /* sin6.sin6_scope_id = XXX: should be set if DST is a scoped addr */ 1129 rt = rtalloc1((struct sockaddr *)&sin6, 0, 1130 RTF_CLONING | RTF_PRCLONING); 1131 1132 if (rt && (rt->rt_flags & RTF_HOST) 1133 && !(rt->rt_rmx.rmx_locks & RTV_MTU)) { 1134 if (mtu < IPV6_MMTU) { 1135 /* xxx */ 1136 rt->rt_rmx.rmx_locks |= RTV_MTU; 1137 } else if (mtu < rt->rt_ifp->if_mtu && 1138 rt->rt_rmx.rmx_mtu > mtu) { 1139 icmp6stat.icp6s_pmtuchg++; 1140 rt->rt_rmx.rmx_mtu = mtu; 1141 } 1142 } 1143 if (rt) { /* XXX: need braces to avoid conflict with else in RTFREE. */ 1144 RTFREE(rt); 1145 } 1146 } 1147 1148 /* 1149 * Process a Node Information Query packet, based on 1150 * draft-ietf-ipngwg-icmp-name-lookups-07. 1151 * 1152 * Spec incompatibilities: 1153 * - IPv6 Subject address handling 1154 * - IPv4 Subject address handling support missing 1155 * - Proxy reply (answer even if it's not for me) 1156 * - joins NI group address at in6_ifattach() time only, does not cope 1157 * with hostname changes by sethostname(3) 1158 */ 1159 #define hostnamelen strlen(hostname) 1160 static struct mbuf * 1161 ni6_input(m, off) 1162 struct mbuf *m; 1163 int off; 1164 { 1165 struct icmp6_nodeinfo *ni6, *nni6; 1166 struct mbuf *n = NULL; 1167 u_int16_t qtype; 1168 int subjlen; 1169 int replylen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo); 1170 struct ni_reply_fqdn *fqdn; 1171 int addrs; /* for NI_QTYPE_NODEADDR */ 1172 struct ifnet *ifp = NULL; /* for NI_QTYPE_NODEADDR */ 1173 struct sockaddr_in6 sin6; /* double meaning; ip6_dst and subjectaddr */ 1174 struct sockaddr_in6 sin6_d; /* XXX: we should retrieve this from m_aux */ 1175 struct ip6_hdr *ip6; 1176 int oldfqdn = 0; /* if 1, return pascal string (03 draft) */ 1177 char *subj = NULL; 1178 struct in6_ifaddr *ia6 = NULL; 1179 1180 ip6 = mtod(m, struct ip6_hdr *); 1181 #ifndef PULLDOWN_TEST 1182 ni6 = (struct icmp6_nodeinfo *)(mtod(m, caddr_t) + off); 1183 #else 1184 IP6_EXTHDR_GET(ni6, struct icmp6_nodeinfo *, m, off, sizeof(*ni6)); 1185 if (ni6 == NULL) { 1186 /* m is already reclaimed */ 1187 return NULL; 1188 } 1189 #endif 1190 1191 /* 1192 * Validate IPv6 destination address. 1193 * 1194 * The Responder must discard the Query without further processing 1195 * unless it is one of the Responder's unicast or anycast addresses, or 1196 * a link-local scope multicast address which the Responder has joined. 1197 * [icmp-name-lookups-07, Section 4.] 1198 */ 1199 bzero(&sin6, sizeof(sin6)); 1200 sin6.sin6_family = AF_INET6; 1201 sin6.sin6_len = sizeof(struct sockaddr_in6); 1202 bcopy(&ip6->ip6_dst, &sin6.sin6_addr, sizeof(sin6.sin6_addr)); 1203 /* XXX scopeid */ 1204 if ((ia6 = (struct in6_ifaddr *)ifa_ifwithaddr((struct sockaddr *)&sin6)) != NULL) { 1205 /* unicast/anycast, fine */ 1206 if ((ia6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 1207 (icmp6_nodeinfo & 4) == 0) { 1208 nd6log((LOG_DEBUG, "ni6_input: ignore node info to " 1209 "a temporary address in %s:%d", 1210 __FILE__, __LINE__)); 1211 goto bad; 1212 } 1213 } else if (IN6_IS_ADDR_MC_LINKLOCAL(&sin6.sin6_addr)) 1214 ; /* link-local multicast, fine */ 1215 else 1216 goto bad; 1217 1218 /* validate query Subject field. */ 1219 qtype = ntohs(ni6->ni_qtype); 1220 subjlen = m->m_pkthdr.len - off - sizeof(struct icmp6_nodeinfo); 1221 switch (qtype) { 1222 case NI_QTYPE_NOOP: 1223 case NI_QTYPE_SUPTYPES: 1224 /* 07 draft */ 1225 if (ni6->ni_code == ICMP6_NI_SUBJ_FQDN && subjlen == 0) 1226 break; 1227 /* FALLTHROUGH */ 1228 case NI_QTYPE_FQDN: 1229 case NI_QTYPE_NODEADDR: 1230 switch (ni6->ni_code) { 1231 case ICMP6_NI_SUBJ_IPV6: 1232 #if ICMP6_NI_SUBJ_IPV6 != 0 1233 case 0: 1234 #endif 1235 /* 1236 * backward compatibility - try to accept 03 draft 1237 * format, where no Subject is present. 1238 */ 1239 if (qtype == NI_QTYPE_FQDN && ni6->ni_code == 0 && 1240 subjlen == 0) { 1241 oldfqdn++; 1242 break; 1243 } 1244 #if ICMP6_NI_SUBJ_IPV6 != 0 1245 if (ni6->ni_code != ICMP6_NI_SUBJ_IPV6) 1246 goto bad; 1247 #endif 1248 1249 if (subjlen != sizeof(sin6.sin6_addr)) 1250 goto bad; 1251 1252 /* 1253 * Validate Subject address. 1254 * 1255 * Not sure what exactly "address belongs to the node" 1256 * means in the spec, is it just unicast, or what? 1257 * 1258 * At this moment we consider Subject address as 1259 * "belong to the node" if the Subject address equals 1260 * to the IPv6 destination address; validation for 1261 * IPv6 destination address should have done enough 1262 * check for us. 1263 * 1264 * We do not do proxy at this moment. 1265 */ 1266 /* m_pulldown instead of copy? */ 1267 m_copydata(m, off + sizeof(struct icmp6_nodeinfo), 1268 subjlen, (caddr_t)&sin6.sin6_addr); 1269 sin6.sin6_scope_id = in6_addr2scopeid(m->m_pkthdr.rcvif, 1270 &sin6.sin6_addr); 1271 #ifndef SCOPEDROUTING 1272 in6_embedscope(&sin6.sin6_addr, &sin6, NULL, NULL); 1273 #endif 1274 bzero(&sin6_d, sizeof(sin6_d)); 1275 sin6_d.sin6_family = AF_INET6; /* not used, actually */ 1276 sin6_d.sin6_len = sizeof(sin6_d); /* ditto */ 1277 sin6_d.sin6_addr = ip6->ip6_dst; 1278 sin6_d.sin6_scope_id = in6_addr2scopeid(m->m_pkthdr.rcvif, 1279 &ip6->ip6_dst); 1280 #ifndef SCOPEDROUTING 1281 in6_embedscope(&sin6_d.sin6_addr, &sin6_d, NULL, NULL); 1282 #endif 1283 subj = (char *)&sin6; 1284 if (SA6_ARE_ADDR_EQUAL(&sin6, &sin6_d)) 1285 break; 1286 1287 /* 1288 * XXX if we are to allow other cases, we should really 1289 * be careful about scope here. 1290 * basically, we should disallow queries toward IPv6 1291 * destination X with subject Y, if scope(X) > scope(Y). 1292 * if we allow scope(X) > scope(Y), it will result in 1293 * information leakage across scope boundary. 1294 */ 1295 goto bad; 1296 1297 case ICMP6_NI_SUBJ_FQDN: 1298 /* 1299 * Validate Subject name with gethostname(3). 1300 * 1301 * The behavior may need some debate, since: 1302 * - we are not sure if the node has FQDN as 1303 * hostname (returned by gethostname(3)). 1304 * - the code does wildcard match for truncated names. 1305 * however, we are not sure if we want to perform 1306 * wildcard match, if gethostname(3) side has 1307 * truncated hostname. 1308 */ 1309 n = ni6_nametodns(hostname, hostnamelen, 0); 1310 if (!n || n->m_next || n->m_len == 0) 1311 goto bad; 1312 IP6_EXTHDR_GET(subj, char *, m, 1313 off + sizeof(struct icmp6_nodeinfo), subjlen); 1314 if (subj == NULL) 1315 goto bad; 1316 if (!ni6_dnsmatch(subj, subjlen, mtod(n, const char *), 1317 n->m_len)) { 1318 goto bad; 1319 } 1320 m_freem(n); 1321 n = NULL; 1322 break; 1323 1324 case ICMP6_NI_SUBJ_IPV4: /* XXX: to be implemented? */ 1325 default: 1326 goto bad; 1327 } 1328 break; 1329 } 1330 1331 /* refuse based on configuration. XXX ICMP6_NI_REFUSED? */ 1332 switch (qtype) { 1333 case NI_QTYPE_FQDN: 1334 if ((icmp6_nodeinfo & 1) == 0) 1335 goto bad; 1336 break; 1337 case NI_QTYPE_NODEADDR: 1338 if ((icmp6_nodeinfo & 2) == 0) 1339 goto bad; 1340 break; 1341 } 1342 1343 /* guess reply length */ 1344 switch (qtype) { 1345 case NI_QTYPE_NOOP: 1346 break; /* no reply data */ 1347 case NI_QTYPE_SUPTYPES: 1348 replylen += sizeof(u_int32_t); 1349 break; 1350 case NI_QTYPE_FQDN: 1351 /* XXX will append an mbuf */ 1352 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1353 break; 1354 case NI_QTYPE_NODEADDR: 1355 addrs = ni6_addrs(ni6, m, &ifp, subj); 1356 if ((replylen += addrs * (sizeof(struct in6_addr) + 1357 sizeof(u_int32_t))) > MCLBYTES) 1358 replylen = MCLBYTES; /* XXX: will truncate pkt later */ 1359 break; 1360 default: 1361 /* 1362 * XXX: We must return a reply with the ICMP6 code 1363 * `unknown Qtype' in this case. However we regard the case 1364 * as an FQDN query for backward compatibility. 1365 * Older versions set a random value to this field, 1366 * so it rarely varies in the defined qtypes. 1367 * But the mechanism is not reliable... 1368 * maybe we should obsolete older versions. 1369 */ 1370 qtype = NI_QTYPE_FQDN; 1371 /* XXX will append an mbuf */ 1372 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1373 oldfqdn++; 1374 break; 1375 } 1376 1377 /* allocate an mbuf to reply. */ 1378 MGETHDR(n, M_DONTWAIT, m->m_type); 1379 if (n == NULL) { 1380 m_freem(m); 1381 return(NULL); 1382 } 1383 M_COPY_PKTHDR(n, m); /* just for recvif */ 1384 if (replylen > MHLEN) { 1385 if (replylen > MCLBYTES) { 1386 /* 1387 * XXX: should we try to allocate more? But MCLBYTES 1388 * is probably much larger than IPV6_MMTU... 1389 */ 1390 goto bad; 1391 } 1392 MCLGET(n, M_DONTWAIT); 1393 if ((n->m_flags & M_EXT) == 0) { 1394 goto bad; 1395 } 1396 } 1397 n->m_pkthdr.len = n->m_len = replylen; 1398 1399 /* copy mbuf header and IPv6 + Node Information base headers */ 1400 bcopy(mtod(m, caddr_t), mtod(n, caddr_t), sizeof(struct ip6_hdr)); 1401 nni6 = (struct icmp6_nodeinfo *)(mtod(n, struct ip6_hdr *) + 1); 1402 bcopy((caddr_t)ni6, (caddr_t)nni6, sizeof(struct icmp6_nodeinfo)); 1403 1404 /* qtype dependent procedure */ 1405 switch (qtype) { 1406 case NI_QTYPE_NOOP: 1407 nni6->ni_code = ICMP6_NI_SUCCESS; 1408 nni6->ni_flags = 0; 1409 break; 1410 case NI_QTYPE_SUPTYPES: 1411 { 1412 u_int32_t v; 1413 nni6->ni_code = ICMP6_NI_SUCCESS; 1414 nni6->ni_flags = htons(0x0000); /* raw bitmap */ 1415 /* supports NOOP, SUPTYPES, FQDN, and NODEADDR */ 1416 v = (u_int32_t)htonl(0x0000000f); 1417 bcopy(&v, nni6 + 1, sizeof(u_int32_t)); 1418 break; 1419 } 1420 case NI_QTYPE_FQDN: 1421 nni6->ni_code = ICMP6_NI_SUCCESS; 1422 fqdn = (struct ni_reply_fqdn *)(mtod(n, caddr_t) + 1423 sizeof(struct ip6_hdr) + 1424 sizeof(struct icmp6_nodeinfo)); 1425 nni6->ni_flags = 0; /* XXX: meaningless TTL */ 1426 fqdn->ni_fqdn_ttl = 0; /* ditto. */ 1427 /* 1428 * XXX do we really have FQDN in variable "hostname"? 1429 */ 1430 n->m_next = ni6_nametodns(hostname, hostnamelen, oldfqdn); 1431 if (n->m_next == NULL) 1432 goto bad; 1433 /* XXX we assume that n->m_next is not a chain */ 1434 if (n->m_next->m_next != NULL) 1435 goto bad; 1436 n->m_pkthdr.len += n->m_next->m_len; 1437 break; 1438 case NI_QTYPE_NODEADDR: 1439 { 1440 int lenlim, copied; 1441 1442 nni6->ni_code = ICMP6_NI_SUCCESS; 1443 n->m_pkthdr.len = n->m_len = 1444 sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo); 1445 lenlim = M_TRAILINGSPACE(n); 1446 copied = ni6_store_addrs(ni6, nni6, ifp, lenlim); 1447 /* XXX: reset mbuf length */ 1448 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) + 1449 sizeof(struct icmp6_nodeinfo) + copied; 1450 break; 1451 } 1452 default: 1453 break; /* XXX impossible! */ 1454 } 1455 1456 nni6->ni_type = ICMP6_NI_REPLY; 1457 m_freem(m); 1458 return(n); 1459 1460 bad: 1461 m_freem(m); 1462 if (n) 1463 m_freem(n); 1464 return(NULL); 1465 } 1466 #undef hostnamelen 1467 1468 /* 1469 * make a mbuf with DNS-encoded string. no compression support. 1470 * 1471 * XXX names with less than 2 dots (like "foo" or "foo.section") will be 1472 * treated as truncated name (two \0 at the end). this is a wild guess. 1473 */ 1474 static struct mbuf * 1475 ni6_nametodns(name, namelen, old) 1476 const char *name; 1477 int namelen; 1478 int old; /* return pascal string if non-zero */ 1479 { 1480 struct mbuf *m; 1481 char *cp, *ep; 1482 const char *p, *q; 1483 int i, len, nterm; 1484 1485 if (old) 1486 len = namelen + 1; 1487 else 1488 len = MCLBYTES; 1489 1490 /* because MAXHOSTNAMELEN is usually 256, we use cluster mbuf */ 1491 MGET(m, M_DONTWAIT, MT_DATA); 1492 if (m && len > MLEN) { 1493 MCLGET(m, M_DONTWAIT); 1494 if ((m->m_flags & M_EXT) == 0) 1495 goto fail; 1496 } 1497 if (!m) 1498 goto fail; 1499 m->m_next = NULL; 1500 1501 if (old) { 1502 m->m_len = len; 1503 *mtod(m, char *) = namelen; 1504 bcopy(name, mtod(m, char *) + 1, namelen); 1505 return m; 1506 } else { 1507 m->m_len = 0; 1508 cp = mtod(m, char *); 1509 ep = mtod(m, char *) + M_TRAILINGSPACE(m); 1510 1511 /* if not certain about my name, return empty buffer */ 1512 if (namelen == 0) 1513 return m; 1514 1515 /* 1516 * guess if it looks like shortened hostname, or FQDN. 1517 * shortened hostname needs two trailing "\0". 1518 */ 1519 i = 0; 1520 for (p = name; p < name + namelen; p++) { 1521 if (*p && *p == '.') 1522 i++; 1523 } 1524 if (i < 2) 1525 nterm = 2; 1526 else 1527 nterm = 1; 1528 1529 p = name; 1530 while (cp < ep && p < name + namelen) { 1531 i = 0; 1532 for (q = p; q < name + namelen && *q && *q != '.'; q++) 1533 i++; 1534 /* result does not fit into mbuf */ 1535 if (cp + i + 1 >= ep) 1536 goto fail; 1537 /* 1538 * DNS label length restriction, RFC1035 page 8. 1539 * "i == 0" case is included here to avoid returning 1540 * 0-length label on "foo..bar". 1541 */ 1542 if (i <= 0 || i >= 64) 1543 goto fail; 1544 *cp++ = i; 1545 bcopy(p, cp, i); 1546 cp += i; 1547 p = q; 1548 if (p < name + namelen && *p == '.') 1549 p++; 1550 } 1551 /* termination */ 1552 if (cp + nterm >= ep) 1553 goto fail; 1554 while (nterm-- > 0) 1555 *cp++ = '\0'; 1556 m->m_len = cp - mtod(m, char *); 1557 return m; 1558 } 1559 1560 panic("should not reach here"); 1561 /* NOTREACHED */ 1562 1563 fail: 1564 if (m) 1565 m_freem(m); 1566 return NULL; 1567 } 1568 1569 /* 1570 * check if two DNS-encoded string matches. takes care of truncated 1571 * form (with \0\0 at the end). no compression support. 1572 * XXX upper/lowercase match (see RFC2065) 1573 */ 1574 static int 1575 ni6_dnsmatch(a, alen, b, blen) 1576 const char *a; 1577 int alen; 1578 const char *b; 1579 int blen; 1580 { 1581 const char *a0, *b0; 1582 int l; 1583 1584 /* simplest case - need validation? */ 1585 if (alen == blen && bcmp(a, b, alen) == 0) 1586 return 1; 1587 1588 a0 = a; 1589 b0 = b; 1590 1591 /* termination is mandatory */ 1592 if (alen < 2 || blen < 2) 1593 return 0; 1594 if (a0[alen - 1] != '\0' || b0[blen - 1] != '\0') 1595 return 0; 1596 alen--; 1597 blen--; 1598 1599 while (a - a0 < alen && b - b0 < blen) { 1600 if (a - a0 + 1 > alen || b - b0 + 1 > blen) 1601 return 0; 1602 1603 if ((signed char)a[0] < 0 || (signed char)b[0] < 0) 1604 return 0; 1605 /* we don't support compression yet */ 1606 if (a[0] >= 64 || b[0] >= 64) 1607 return 0; 1608 1609 /* truncated case */ 1610 if (a[0] == 0 && a - a0 == alen - 1) 1611 return 1; 1612 if (b[0] == 0 && b - b0 == blen - 1) 1613 return 1; 1614 if (a[0] == 0 || b[0] == 0) 1615 return 0; 1616 1617 if (a[0] != b[0]) 1618 return 0; 1619 l = a[0]; 1620 if (a - a0 + 1 + l > alen || b - b0 + 1 + l > blen) 1621 return 0; 1622 if (bcmp(a + 1, b + 1, l) != 0) 1623 return 0; 1624 1625 a += 1 + l; 1626 b += 1 + l; 1627 } 1628 1629 if (a - a0 == alen && b - b0 == blen) 1630 return 1; 1631 else 1632 return 0; 1633 } 1634 1635 /* 1636 * calculate the number of addresses to be returned in the node info reply. 1637 */ 1638 static int 1639 ni6_addrs(ni6, m, ifpp, subj) 1640 struct icmp6_nodeinfo *ni6; 1641 struct mbuf *m; 1642 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(ni6, nni6, ifp0, resid) 1736 struct icmp6_nodeinfo *ni6, *nni6; 1737 struct ifnet *ifp0; 1738 int resid; 1739 { 1740 struct ifnet *ifp = ifp0 ? ifp0 : TAILQ_FIRST(&ifnet); 1741 struct in6_ifaddr *ifa6; 1742 struct ifaddr *ifa; 1743 struct ifnet *ifp_dep = NULL; 1744 int copied = 0, allow_deprecated = 0; 1745 u_char *cp = (u_char *)(nni6 + 1); 1746 int niflags = ni6->ni_flags; 1747 u_int32_t ltime; 1748 1749 if (ifp0 == NULL && !(niflags & NI_NODEADDR_FLAG_ALL)) 1750 return(0); /* needless to copy */ 1751 1752 again: 1753 1754 for (; ifp; ifp = TAILQ_NEXT(ifp, if_list)) 1755 { 1756 for (ifa = ifp->if_addrlist.tqh_first; ifa; 1757 ifa = ifa->ifa_list.tqe_next) 1758 { 1759 if (ifa->ifa_addr->sa_family != AF_INET6) 1760 continue; 1761 ifa6 = (struct in6_ifaddr *)ifa; 1762 1763 if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) != 0 && 1764 allow_deprecated == 0) { 1765 /* 1766 * prefererred address should be put before 1767 * deprecated addresses. 1768 */ 1769 1770 /* record the interface for later search */ 1771 if (ifp_dep == NULL) 1772 ifp_dep = ifp; 1773 1774 continue; 1775 } 1776 else if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) == 0 && 1777 allow_deprecated != 0) 1778 continue; /* we now collect deprecated addrs */ 1779 1780 /* What do we have to do about ::1? */ 1781 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1782 case IPV6_ADDR_SCOPE_LINKLOCAL: 1783 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0) 1784 continue; 1785 break; 1786 case IPV6_ADDR_SCOPE_SITELOCAL: 1787 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0) 1788 continue; 1789 break; 1790 case IPV6_ADDR_SCOPE_GLOBAL: 1791 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0) 1792 continue; 1793 break; 1794 default: 1795 continue; 1796 } 1797 1798 /* 1799 * check if anycast is okay. 1800 * XXX: just experimental. not in the spec. 1801 */ 1802 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 && 1803 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0) 1804 continue; 1805 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 1806 (icmp6_nodeinfo & 4) == 0) { 1807 continue; 1808 } 1809 1810 /* now we can copy the address */ 1811 if (resid < sizeof(struct in6_addr) + 1812 sizeof(u_int32_t)) { 1813 /* 1814 * We give up much more copy. 1815 * Set the truncate flag and return. 1816 */ 1817 nni6->ni_flags |= 1818 NI_NODEADDR_FLAG_TRUNCATE; 1819 return(copied); 1820 } 1821 1822 /* 1823 * Set the TTL of the address. 1824 * The TTL value should be one of the following 1825 * according to the specification: 1826 * 1827 * 1. The remaining lifetime of a DHCP lease on the 1828 * address, or 1829 * 2. The remaining Valid Lifetime of a prefix from 1830 * which the address was derived through Stateless 1831 * Autoconfiguration. 1832 * 1833 * Note that we currently do not support stateful 1834 * address configuration by DHCPv6, so the former 1835 * case can't happen. 1836 */ 1837 if (ifa6->ia6_lifetime.ia6t_expire == 0) 1838 ltime = ND6_INFINITE_LIFETIME; 1839 else { 1840 if (ifa6->ia6_lifetime.ia6t_expire > 1841 time_second) 1842 ltime = htonl(ifa6->ia6_lifetime.ia6t_expire - time_second); 1843 else 1844 ltime = 0; 1845 } 1846 1847 bcopy(<ime, cp, sizeof(u_int32_t)); 1848 cp += sizeof(u_int32_t); 1849 1850 /* copy the address itself */ 1851 bcopy(&ifa6->ia_addr.sin6_addr, cp, 1852 sizeof(struct in6_addr)); 1853 /* XXX: KAME link-local hack; remove ifindex */ 1854 if (IN6_IS_ADDR_LINKLOCAL(&ifa6->ia_addr.sin6_addr)) 1855 ((struct in6_addr *)cp)->s6_addr16[1] = 0; 1856 cp += sizeof(struct in6_addr); 1857 1858 resid -= (sizeof(struct in6_addr) + sizeof(u_int32_t)); 1859 copied += (sizeof(struct in6_addr) + 1860 sizeof(u_int32_t)); 1861 } 1862 if (ifp0) /* we need search only on the specified IF */ 1863 break; 1864 } 1865 1866 if (allow_deprecated == 0 && ifp_dep != NULL) { 1867 ifp = ifp_dep; 1868 allow_deprecated = 1; 1869 1870 goto again; 1871 } 1872 1873 return(copied); 1874 } 1875 1876 /* 1877 * XXX almost dup'ed code with rip6_input. 1878 */ 1879 static int 1880 icmp6_rip6_input(mp, off) 1881 struct mbuf **mp; 1882 int off; 1883 { 1884 struct mbuf *m = *mp; 1885 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1886 struct in6pcb *in6p; 1887 struct in6pcb *last = NULL; 1888 struct sockaddr_in6 rip6src; 1889 struct icmp6_hdr *icmp6; 1890 struct mbuf *opts = NULL; 1891 1892 #ifndef PULLDOWN_TEST 1893 /* this is assumed to be safe. */ 1894 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off); 1895 #else 1896 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 1897 if (icmp6 == NULL) { 1898 /* m is already reclaimed */ 1899 return IPPROTO_DONE; 1900 } 1901 #endif 1902 1903 bzero(&rip6src, sizeof(rip6src)); 1904 rip6src.sin6_len = sizeof(struct sockaddr_in6); 1905 rip6src.sin6_family = AF_INET6; 1906 /* KAME hack: recover scopeid */ 1907 (void)in6_recoverscope(&rip6src, &ip6->ip6_src, m->m_pkthdr.rcvif); 1908 1909 LIST_FOREACH(in6p, &ripcb, inp_list) 1910 { 1911 if ((in6p->inp_vflag & INP_IPV6) == 0) 1912 continue; 1913 #ifdef HAVE_NRL_INPCB 1914 if (!(in6p->in6p_flags & INP_IPV6)) 1915 continue; 1916 #endif 1917 if (in6p->in6p_ip6_nxt != IPPROTO_ICMPV6) 1918 continue; 1919 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr) && 1920 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr, &ip6->ip6_dst)) 1921 continue; 1922 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr) && 1923 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr, &ip6->ip6_src)) 1924 continue; 1925 if (in6p->in6p_icmp6filt 1926 && ICMP6_FILTER_WILLBLOCK(icmp6->icmp6_type, 1927 in6p->in6p_icmp6filt)) 1928 continue; 1929 if (last) { 1930 struct mbuf *n; 1931 if ((n = m_copy(m, 0, (int)M_COPYALL)) != NULL) { 1932 if (last->in6p_flags & IN6P_CONTROLOPTS) 1933 ip6_savecontrol(last, &opts, ip6, n); 1934 /* strip intermediate headers */ 1935 m_adj(n, off); 1936 if (sbappendaddr(&last->in6p_socket->so_rcv, 1937 (struct sockaddr *)&rip6src, 1938 n, opts) == 0) { 1939 /* should notify about lost packet */ 1940 m_freem(n); 1941 if (opts) { 1942 m_freem(opts); 1943 } 1944 } else 1945 sorwakeup(last->in6p_socket); 1946 opts = NULL; 1947 } 1948 } 1949 last = in6p; 1950 } 1951 if (last) { 1952 if (last->in6p_flags & IN6P_CONTROLOPTS) 1953 ip6_savecontrol(last, &opts, ip6, m); 1954 /* strip intermediate headers */ 1955 m_adj(m, off); 1956 if (sbappendaddr(&last->in6p_socket->so_rcv, 1957 (struct sockaddr *)&rip6src, m, opts) == 0) { 1958 m_freem(m); 1959 if (opts) 1960 m_freem(opts); 1961 } else 1962 sorwakeup(last->in6p_socket); 1963 } else { 1964 m_freem(m); 1965 ip6stat.ip6s_delivered--; 1966 } 1967 return IPPROTO_DONE; 1968 } 1969 1970 /* 1971 * Reflect the ip6 packet back to the source. 1972 * OFF points to the icmp6 header, counted from the top of the mbuf. 1973 */ 1974 void 1975 icmp6_reflect(m, off) 1976 struct mbuf *m; 1977 size_t off; 1978 { 1979 struct ip6_hdr *ip6; 1980 struct icmp6_hdr *icmp6; 1981 struct in6_ifaddr *ia; 1982 struct in6_addr t, *src = 0; 1983 int plen; 1984 int type, code; 1985 struct ifnet *outif = NULL; 1986 struct sockaddr_in6 sa6_src, sa6_dst; 1987 #ifdef COMPAT_RFC1885 1988 int mtu = IPV6_MMTU; 1989 struct sockaddr_in6 *sin6 = &icmp6_reflect_rt.ro_dst; 1990 #endif 1991 1992 /* too short to reflect */ 1993 if (off < sizeof(struct ip6_hdr)) { 1994 nd6log((LOG_DEBUG, 1995 "sanity fail: off=%lx, sizeof(ip6)=%lx in %s:%d\n", 1996 (u_long)off, (u_long)sizeof(struct ip6_hdr), 1997 __FILE__, __LINE__)); 1998 goto bad; 1999 } 2000 2001 /* 2002 * If there are extra headers between IPv6 and ICMPv6, strip 2003 * off that header first. 2004 */ 2005 #ifdef DIAGNOSTIC 2006 if (sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) > MHLEN) 2007 panic("assumption failed in icmp6_reflect"); 2008 #endif 2009 if (off > sizeof(struct ip6_hdr)) { 2010 size_t l; 2011 struct ip6_hdr nip6; 2012 2013 l = off - sizeof(struct ip6_hdr); 2014 m_copydata(m, 0, sizeof(nip6), (caddr_t)&nip6); 2015 m_adj(m, l); 2016 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 2017 if (m->m_len < l) { 2018 if ((m = m_pullup(m, l)) == NULL) 2019 return; 2020 } 2021 bcopy((caddr_t)&nip6, mtod(m, caddr_t), sizeof(nip6)); 2022 } else /* off == sizeof(struct ip6_hdr) */ { 2023 size_t l; 2024 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 2025 if (m->m_len < l) { 2026 if ((m = m_pullup(m, l)) == NULL) 2027 return; 2028 } 2029 } 2030 plen = m->m_pkthdr.len - sizeof(struct ip6_hdr); 2031 ip6 = mtod(m, struct ip6_hdr *); 2032 ip6->ip6_nxt = IPPROTO_ICMPV6; 2033 icmp6 = (struct icmp6_hdr *)(ip6 + 1); 2034 type = icmp6->icmp6_type; /* keep type for statistics */ 2035 code = icmp6->icmp6_code; /* ditto. */ 2036 2037 t = ip6->ip6_dst; 2038 /* 2039 * ip6_input() drops a packet if its src is multicast. 2040 * So, the src is never multicast. 2041 */ 2042 ip6->ip6_dst = ip6->ip6_src; 2043 2044 /* 2045 * XXX: make sure to embed scope zone information, using 2046 * already embedded IDs or the received interface (if any). 2047 * Note that rcvif may be NULL. 2048 * TODO: scoped routing case (XXX). 2049 */ 2050 bzero(&sa6_src, sizeof(sa6_src)); 2051 sa6_src.sin6_family = AF_INET6; 2052 sa6_src.sin6_len = sizeof(sa6_src); 2053 sa6_src.sin6_addr = ip6->ip6_dst; 2054 in6_recoverscope(&sa6_src, &ip6->ip6_dst, m->m_pkthdr.rcvif); 2055 in6_embedscope(&ip6->ip6_dst, &sa6_src, NULL, NULL); 2056 bzero(&sa6_dst, sizeof(sa6_dst)); 2057 sa6_dst.sin6_family = AF_INET6; 2058 sa6_dst.sin6_len = sizeof(sa6_dst); 2059 sa6_dst.sin6_addr = t; 2060 in6_recoverscope(&sa6_dst, &t, m->m_pkthdr.rcvif); 2061 in6_embedscope(&t, &sa6_dst, NULL, NULL); 2062 2063 #ifdef COMPAT_RFC1885 2064 /* 2065 * xxx guess MTU 2066 * RFC 1885 requires that echo reply should be truncated if it 2067 * does not fit in with (return) path MTU, but the description was 2068 * removed in the new spec. 2069 */ 2070 if (icmp6_reflect_rt.ro_rt == 0 || 2071 ! (IN6_ARE_ADDR_EQUAL(&sin6->sin6_addr, &ip6->ip6_dst))) { 2072 if (icmp6_reflect_rt.ro_rt) { 2073 RTFREE(icmp6_reflect_rt.ro_rt); 2074 icmp6_reflect_rt.ro_rt = 0; 2075 } 2076 bzero(sin6, sizeof(*sin6)); 2077 sin6->sin6_family = PF_INET6; 2078 sin6->sin6_len = sizeof(struct sockaddr_in6); 2079 sin6->sin6_addr = ip6->ip6_dst; 2080 2081 rtalloc_ign((struct route *)&icmp6_reflect_rt.ro_rt, 2082 RTF_PRCLONING); 2083 } 2084 2085 if (icmp6_reflect_rt.ro_rt == 0) 2086 goto bad; 2087 2088 if ((icmp6_reflect_rt.ro_rt->rt_flags & RTF_HOST) 2089 && mtu < icmp6_reflect_rt.ro_rt->rt_ifp->if_mtu) 2090 mtu = icmp6_reflect_rt.ro_rt->rt_rmx.rmx_mtu; 2091 2092 if (mtu < m->m_pkthdr.len) { 2093 plen -= (m->m_pkthdr.len - mtu); 2094 m_adj(m, mtu - m->m_pkthdr.len); 2095 } 2096 #endif 2097 /* 2098 * If the incoming packet was addressed directly to us(i.e. unicast), 2099 * use dst as the src for the reply. 2100 * The IN6_IFF_NOTREADY case would be VERY rare, but is possible 2101 * (for example) when we encounter an error while forwarding procedure 2102 * destined to a duplicated address of ours. 2103 */ 2104 for (ia = in6_ifaddr; ia; ia = ia->ia_next) 2105 if (IN6_ARE_ADDR_EQUAL(&t, &ia->ia_addr.sin6_addr) && 2106 (ia->ia6_flags & (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY)) == 0) { 2107 src = &t; 2108 break; 2109 } 2110 if (ia == NULL && IN6_IS_ADDR_LINKLOCAL(&t) && (m->m_flags & M_LOOP)) { 2111 /* 2112 * This is the case if the dst is our link-local address 2113 * and the sender is also ourselves. 2114 */ 2115 src = &t; 2116 } 2117 2118 if (src == 0) { 2119 int e; 2120 struct route_in6 ro; 2121 2122 /* 2123 * This case matches to multicasts, our anycast, or unicasts 2124 * that we do not own. Select a source address based on the 2125 * source address of the erroneous packet. 2126 */ 2127 bzero(&ro, sizeof(ro)); 2128 src = in6_selectsrc(&sa6_src, NULL, NULL, &ro, NULL, &e); 2129 if (ro.ro_rt) 2130 RTFREE(ro.ro_rt); /* XXX: we could use this */ 2131 if (src == NULL) { 2132 nd6log((LOG_DEBUG, 2133 "icmp6_reflect: source can't be determined: " 2134 "dst=%s, error=%d\n", 2135 ip6_sprintf(&sa6_src.sin6_addr), e)); 2136 goto bad; 2137 } 2138 } 2139 2140 ip6->ip6_src = *src; 2141 2142 ip6->ip6_flow = 0; 2143 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2144 ip6->ip6_vfc |= IPV6_VERSION; 2145 ip6->ip6_nxt = IPPROTO_ICMPV6; 2146 if (m->m_pkthdr.rcvif) { 2147 /* XXX: This may not be the outgoing interface */ 2148 ip6->ip6_hlim = nd_ifinfo[m->m_pkthdr.rcvif->if_index].chlim; 2149 } else 2150 ip6->ip6_hlim = ip6_defhlim; 2151 2152 icmp6->icmp6_cksum = 0; 2153 icmp6->icmp6_cksum = in6_cksum(m, IPPROTO_ICMPV6, 2154 sizeof(struct ip6_hdr), plen); 2155 2156 /* 2157 * XXX option handling 2158 */ 2159 2160 m->m_flags &= ~(M_BCAST|M_MCAST); 2161 #ifdef IPSEC 2162 /* Don't lookup socket */ 2163 (void)ipsec_setsocket(m, NULL); 2164 #endif /*IPSEC*/ 2165 2166 #ifdef COMPAT_RFC1885 2167 ip6_output(m, NULL, &icmp6_reflect_rt, 0, NULL, &outif); 2168 #else 2169 ip6_output(m, NULL, NULL, 0, NULL, &outif); 2170 #endif 2171 if (outif) 2172 icmp6_ifoutstat_inc(outif, type, code); 2173 2174 return; 2175 2176 bad: 2177 m_freem(m); 2178 return; 2179 } 2180 2181 void 2182 icmp6_fasttimo() 2183 { 2184 2185 mld6_fasttimeo(); 2186 } 2187 2188 static const char * 2189 icmp6_redirect_diag(src6, dst6, tgt6) 2190 struct in6_addr *src6; 2191 struct in6_addr *dst6; 2192 struct in6_addr *tgt6; 2193 { 2194 static char buf[1024]; 2195 snprintf(buf, sizeof(buf), "(src=%s dst=%s tgt=%s)", 2196 ip6_sprintf(src6), ip6_sprintf(dst6), ip6_sprintf(tgt6)); 2197 return buf; 2198 } 2199 2200 void 2201 icmp6_redirect_input(m, off) 2202 struct mbuf *m; 2203 int off; 2204 { 2205 struct ifnet *ifp = m->m_pkthdr.rcvif; 2206 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 2207 struct nd_redirect *nd_rd; 2208 int icmp6len = ntohs(ip6->ip6_plen); 2209 char *lladdr = NULL; 2210 int lladdrlen = 0; 2211 u_char *redirhdr = NULL; 2212 int redirhdrlen = 0; 2213 struct rtentry *rt = NULL; 2214 int is_router; 2215 int is_onlink; 2216 struct in6_addr src6 = ip6->ip6_src; 2217 struct in6_addr redtgt6; 2218 struct in6_addr reddst6; 2219 union nd_opts ndopts; 2220 2221 if (!m || !ifp) 2222 return; 2223 2224 /* XXX if we are router, we don't update route by icmp6 redirect */ 2225 if (ip6_forwarding) 2226 goto freeit; 2227 if (!icmp6_rediraccept) 2228 goto freeit; 2229 2230 #ifndef PULLDOWN_TEST 2231 IP6_EXTHDR_CHECK(m, off, icmp6len,); 2232 nd_rd = (struct nd_redirect *)((caddr_t)ip6 + off); 2233 #else 2234 IP6_EXTHDR_GET(nd_rd, struct nd_redirect *, m, off, icmp6len); 2235 if (nd_rd == NULL) { 2236 icmp6stat.icp6s_tooshort++; 2237 return; 2238 } 2239 #endif 2240 redtgt6 = nd_rd->nd_rd_target; 2241 reddst6 = nd_rd->nd_rd_dst; 2242 2243 if (IN6_IS_ADDR_LINKLOCAL(&redtgt6)) 2244 redtgt6.s6_addr16[1] = htons(ifp->if_index); 2245 if (IN6_IS_ADDR_LINKLOCAL(&reddst6)) 2246 reddst6.s6_addr16[1] = htons(ifp->if_index); 2247 2248 /* validation */ 2249 if (!IN6_IS_ADDR_LINKLOCAL(&src6)) { 2250 nd6log((LOG_ERR, 2251 "ICMP6 redirect sent from %s rejected; " 2252 "must be from linklocal\n", ip6_sprintf(&src6))); 2253 goto bad; 2254 } 2255 if (ip6->ip6_hlim != 255) { 2256 nd6log((LOG_ERR, 2257 "ICMP6 redirect sent from %s rejected; " 2258 "hlim=%d (must be 255)\n", 2259 ip6_sprintf(&src6), ip6->ip6_hlim)); 2260 goto bad; 2261 } 2262 { 2263 /* ip6->ip6_src must be equal to gw for icmp6->icmp6_reddst */ 2264 struct sockaddr_in6 sin6; 2265 struct in6_addr *gw6; 2266 2267 bzero(&sin6, sizeof(sin6)); 2268 sin6.sin6_family = AF_INET6; 2269 sin6.sin6_len = sizeof(struct sockaddr_in6); 2270 bcopy(&reddst6, &sin6.sin6_addr, sizeof(reddst6)); 2271 rt = rtalloc1((struct sockaddr *)&sin6, 0, 0UL); 2272 if (rt) { 2273 if (rt->rt_gateway == NULL || 2274 rt->rt_gateway->sa_family != AF_INET6) { 2275 nd6log((LOG_ERR, 2276 "ICMP6 redirect rejected; no route " 2277 "with inet6 gateway found for redirect dst: %s\n", 2278 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2279 RTFREE(rt); 2280 goto bad; 2281 } 2282 2283 gw6 = &(((struct sockaddr_in6 *)rt->rt_gateway)->sin6_addr); 2284 if (bcmp(&src6, gw6, sizeof(struct in6_addr)) != 0) { 2285 nd6log((LOG_ERR, 2286 "ICMP6 redirect rejected; " 2287 "not equal to gw-for-src=%s (must be same): " 2288 "%s\n", 2289 ip6_sprintf(gw6), 2290 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2291 RTFREE(rt); 2292 goto bad; 2293 } 2294 } else { 2295 nd6log((LOG_ERR, 2296 "ICMP6 redirect rejected; " 2297 "no route found for redirect dst: %s\n", 2298 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2299 goto bad; 2300 } 2301 RTFREE(rt); 2302 rt = NULL; 2303 } 2304 if (IN6_IS_ADDR_MULTICAST(&reddst6)) { 2305 nd6log((LOG_ERR, 2306 "ICMP6 redirect rejected; " 2307 "redirect dst must be unicast: %s\n", 2308 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2309 goto bad; 2310 } 2311 2312 is_router = is_onlink = 0; 2313 if (IN6_IS_ADDR_LINKLOCAL(&redtgt6)) 2314 is_router = 1; /* router case */ 2315 if (bcmp(&redtgt6, &reddst6, sizeof(redtgt6)) == 0) 2316 is_onlink = 1; /* on-link destination case */ 2317 if (!is_router && !is_onlink) { 2318 nd6log((LOG_ERR, 2319 "ICMP6 redirect rejected; " 2320 "neither router case nor onlink case: %s\n", 2321 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2322 goto bad; 2323 } 2324 /* validation passed */ 2325 2326 icmp6len -= sizeof(*nd_rd); 2327 nd6_option_init(nd_rd + 1, icmp6len, &ndopts); 2328 if (nd6_options(&ndopts) < 0) { 2329 nd6log((LOG_INFO, "icmp6_redirect_input: " 2330 "invalid ND option, rejected: %s\n", 2331 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2332 /* nd6_options have incremented stats */ 2333 goto freeit; 2334 } 2335 2336 if (ndopts.nd_opts_tgt_lladdr) { 2337 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 2338 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 2339 } 2340 2341 if (ndopts.nd_opts_rh) { 2342 redirhdrlen = ndopts.nd_opts_rh->nd_opt_rh_len; 2343 redirhdr = (u_char *)(ndopts.nd_opts_rh + 1); /* xxx */ 2344 } 2345 2346 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 2347 nd6log((LOG_INFO, 2348 "icmp6_redirect_input: lladdrlen mismatch for %s " 2349 "(if %d, icmp6 packet %d): %s\n", 2350 ip6_sprintf(&redtgt6), ifp->if_addrlen, lladdrlen - 2, 2351 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2352 goto bad; 2353 } 2354 2355 /* RFC 2461 8.3 */ 2356 nd6_cache_lladdr(ifp, &redtgt6, lladdr, lladdrlen, ND_REDIRECT, 2357 is_onlink ? ND_REDIRECT_ONLINK : ND_REDIRECT_ROUTER); 2358 2359 if (!is_onlink) { /* better router case. perform rtredirect. */ 2360 /* perform rtredirect */ 2361 struct sockaddr_in6 sdst; 2362 struct sockaddr_in6 sgw; 2363 struct sockaddr_in6 ssrc; 2364 2365 bzero(&sdst, sizeof(sdst)); 2366 bzero(&sgw, sizeof(sgw)); 2367 bzero(&ssrc, sizeof(ssrc)); 2368 sdst.sin6_family = sgw.sin6_family = ssrc.sin6_family = AF_INET6; 2369 sdst.sin6_len = sgw.sin6_len = ssrc.sin6_len = 2370 sizeof(struct sockaddr_in6); 2371 bcopy(&redtgt6, &sgw.sin6_addr, sizeof(struct in6_addr)); 2372 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2373 bcopy(&src6, &ssrc.sin6_addr, sizeof(struct in6_addr)); 2374 rtredirect((struct sockaddr *)&sdst, (struct sockaddr *)&sgw, 2375 (struct sockaddr *)NULL, RTF_GATEWAY | RTF_HOST, 2376 (struct sockaddr *)&ssrc, 2377 (struct rtentry **)NULL); 2378 } 2379 /* finally update cached route in each socket via pfctlinput */ 2380 { 2381 struct sockaddr_in6 sdst; 2382 2383 bzero(&sdst, sizeof(sdst)); 2384 sdst.sin6_family = AF_INET6; 2385 sdst.sin6_len = sizeof(struct sockaddr_in6); 2386 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2387 pfctlinput(PRC_REDIRECT_HOST, (struct sockaddr *)&sdst); 2388 #ifdef IPSEC 2389 key_sa_routechange((struct sockaddr *)&sdst); 2390 #endif 2391 } 2392 2393 freeit: 2394 m_freem(m); 2395 return; 2396 2397 bad: 2398 icmp6stat.icp6s_badredirect++; 2399 m_freem(m); 2400 } 2401 2402 void 2403 icmp6_redirect_output(m0, rt) 2404 struct mbuf *m0; 2405 struct rtentry *rt; 2406 { 2407 struct ifnet *ifp; /* my outgoing interface */ 2408 struct in6_addr *ifp_ll6; 2409 struct in6_addr *router_ll6; 2410 struct ip6_hdr *sip6; /* m0 as struct ip6_hdr */ 2411 struct mbuf *m = NULL; /* newly allocated one */ 2412 struct ip6_hdr *ip6; /* m as struct ip6_hdr */ 2413 struct nd_redirect *nd_rd; 2414 size_t maxlen; 2415 u_char *p; 2416 struct ifnet *outif = NULL; 2417 struct sockaddr_in6 src_sa; 2418 2419 icmp6_errcount(&icmp6stat.icp6s_outerrhist, ND_REDIRECT, 0); 2420 2421 /* if we are not router, we don't send icmp6 redirect */ 2422 if (!ip6_forwarding || ip6_accept_rtadv) 2423 goto fail; 2424 2425 /* sanity check */ 2426 if (!m0 || !rt || !(rt->rt_flags & RTF_UP) || !(ifp = rt->rt_ifp)) 2427 goto fail; 2428 2429 /* 2430 * Address check: 2431 * the source address must identify a neighbor, and 2432 * the destination address must not be a multicast address 2433 * [RFC 2461, sec 8.2] 2434 */ 2435 sip6 = mtod(m0, struct ip6_hdr *); 2436 bzero(&src_sa, sizeof(src_sa)); 2437 src_sa.sin6_family = AF_INET6; 2438 src_sa.sin6_len = sizeof(src_sa); 2439 src_sa.sin6_addr = sip6->ip6_src; 2440 /* we don't currently use sin6_scope_id, but eventually use it */ 2441 src_sa.sin6_scope_id = in6_addr2scopeid(ifp, &sip6->ip6_src); 2442 if (nd6_is_addr_neighbor(&src_sa, ifp) == 0) 2443 goto fail; 2444 if (IN6_IS_ADDR_MULTICAST(&sip6->ip6_dst)) 2445 goto fail; /* what should we do here? */ 2446 2447 /* rate limit */ 2448 if (icmp6_ratelimit(&sip6->ip6_src, ND_REDIRECT, 0)) 2449 goto fail; 2450 2451 /* 2452 * Since we are going to append up to 1280 bytes (= IPV6_MMTU), 2453 * we almost always ask for an mbuf cluster for simplicity. 2454 * (MHLEN < IPV6_MMTU is almost always true) 2455 */ 2456 #if IPV6_MMTU >= MCLBYTES 2457 # error assumption failed about IPV6_MMTU and MCLBYTES 2458 #endif 2459 MGETHDR(m, M_DONTWAIT, MT_HEADER); 2460 if (m && IPV6_MMTU >= MHLEN) 2461 MCLGET(m, M_DONTWAIT); 2462 if (!m) 2463 goto fail; 2464 m->m_pkthdr.rcvif = NULL; 2465 m->m_len = 0; 2466 maxlen = M_TRAILINGSPACE(m); 2467 maxlen = min(IPV6_MMTU, maxlen); 2468 /* just for safety */ 2469 if (maxlen < sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) + 2470 ((sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7)) { 2471 goto fail; 2472 } 2473 2474 { 2475 /* get ip6 linklocal address for ifp(my outgoing interface). */ 2476 struct in6_ifaddr *ia; 2477 if ((ia = in6ifa_ifpforlinklocal(ifp, 2478 IN6_IFF_NOTREADY| 2479 IN6_IFF_ANYCAST)) == NULL) 2480 goto fail; 2481 ifp_ll6 = &ia->ia_addr.sin6_addr; 2482 } 2483 2484 /* get ip6 linklocal address for the router. */ 2485 if (rt->rt_gateway && (rt->rt_flags & RTF_GATEWAY)) { 2486 struct sockaddr_in6 *sin6; 2487 sin6 = (struct sockaddr_in6 *)rt->rt_gateway; 2488 router_ll6 = &sin6->sin6_addr; 2489 if (!IN6_IS_ADDR_LINKLOCAL(router_ll6)) 2490 router_ll6 = (struct in6_addr *)NULL; 2491 } else 2492 router_ll6 = (struct in6_addr *)NULL; 2493 2494 /* ip6 */ 2495 ip6 = mtod(m, struct ip6_hdr *); 2496 ip6->ip6_flow = 0; 2497 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2498 ip6->ip6_vfc |= IPV6_VERSION; 2499 /* ip6->ip6_plen will be set later */ 2500 ip6->ip6_nxt = IPPROTO_ICMPV6; 2501 ip6->ip6_hlim = 255; 2502 /* ip6->ip6_src must be linklocal addr for my outgoing if. */ 2503 bcopy(ifp_ll6, &ip6->ip6_src, sizeof(struct in6_addr)); 2504 bcopy(&sip6->ip6_src, &ip6->ip6_dst, sizeof(struct in6_addr)); 2505 2506 /* ND Redirect */ 2507 nd_rd = (struct nd_redirect *)(ip6 + 1); 2508 nd_rd->nd_rd_type = ND_REDIRECT; 2509 nd_rd->nd_rd_code = 0; 2510 nd_rd->nd_rd_reserved = 0; 2511 if (rt->rt_flags & RTF_GATEWAY) { 2512 /* 2513 * nd_rd->nd_rd_target must be a link-local address in 2514 * better router cases. 2515 */ 2516 if (!router_ll6) 2517 goto fail; 2518 bcopy(router_ll6, &nd_rd->nd_rd_target, 2519 sizeof(nd_rd->nd_rd_target)); 2520 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2521 sizeof(nd_rd->nd_rd_dst)); 2522 } else { 2523 /* make sure redtgt == reddst */ 2524 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_target, 2525 sizeof(nd_rd->nd_rd_target)); 2526 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2527 sizeof(nd_rd->nd_rd_dst)); 2528 } 2529 2530 p = (u_char *)(nd_rd + 1); 2531 2532 if (!router_ll6) 2533 goto nolladdropt; 2534 2535 { 2536 /* target lladdr option */ 2537 struct rtentry *rt_router = NULL; 2538 int len; 2539 struct sockaddr_dl *sdl; 2540 struct nd_opt_hdr *nd_opt; 2541 char *lladdr; 2542 2543 rt_router = nd6_lookup(router_ll6, 0, ifp); 2544 if (!rt_router) 2545 goto nolladdropt; 2546 len = sizeof(*nd_opt) + ifp->if_addrlen; 2547 len = (len + 7) & ~7; /* round by 8 */ 2548 /* safety check */ 2549 if (len + (p - (u_char *)ip6) > maxlen) 2550 goto nolladdropt; 2551 if (!(rt_router->rt_flags & RTF_GATEWAY) && 2552 (rt_router->rt_flags & RTF_LLINFO) && 2553 (rt_router->rt_gateway->sa_family == AF_LINK) && 2554 (sdl = (struct sockaddr_dl *)rt_router->rt_gateway) && 2555 sdl->sdl_alen) { 2556 nd_opt = (struct nd_opt_hdr *)p; 2557 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 2558 nd_opt->nd_opt_len = len >> 3; 2559 lladdr = (char *)(nd_opt + 1); 2560 bcopy(LLADDR(sdl), lladdr, ifp->if_addrlen); 2561 p += len; 2562 } 2563 } 2564 nolladdropt:; 2565 2566 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2567 2568 /* just to be safe */ 2569 #ifdef M_DECRYPTED /*not openbsd*/ 2570 if (m0->m_flags & M_DECRYPTED) 2571 goto noredhdropt; 2572 #endif 2573 if (p - (u_char *)ip6 > maxlen) 2574 goto noredhdropt; 2575 2576 { 2577 /* redirected header option */ 2578 int len; 2579 struct nd_opt_rd_hdr *nd_opt_rh; 2580 2581 /* 2582 * compute the maximum size for icmp6 redirect header option. 2583 * XXX room for auth header? 2584 */ 2585 len = maxlen - (p - (u_char *)ip6); 2586 len &= ~7; 2587 2588 /* This is just for simplicity. */ 2589 if (m0->m_pkthdr.len != m0->m_len) { 2590 if (m0->m_next) { 2591 m_freem(m0->m_next); 2592 m0->m_next = NULL; 2593 } 2594 m0->m_pkthdr.len = m0->m_len; 2595 } 2596 2597 /* 2598 * Redirected header option spec (RFC2461 4.6.3) talks nothing 2599 * about padding/truncate rule for the original IP packet. 2600 * From the discussion on IPv6imp in Feb 1999, the consensus was: 2601 * - "attach as much as possible" is the goal 2602 * - pad if not aligned (original size can be guessed by original 2603 * ip6 header) 2604 * Following code adds the padding if it is simple enough, 2605 * and truncates if not. 2606 */ 2607 if (m0->m_next || m0->m_pkthdr.len != m0->m_len) 2608 panic("assumption failed in %s:%d\n", __FILE__, __LINE__); 2609 2610 if (len - sizeof(*nd_opt_rh) < m0->m_pkthdr.len) { 2611 /* not enough room, truncate */ 2612 m0->m_pkthdr.len = m0->m_len = len - sizeof(*nd_opt_rh); 2613 } else { 2614 /* enough room, pad or truncate */ 2615 size_t extra; 2616 2617 extra = m0->m_pkthdr.len % 8; 2618 if (extra) { 2619 /* pad if easy enough, truncate if not */ 2620 if (8 - extra <= M_TRAILINGSPACE(m0)) { 2621 /* pad */ 2622 m0->m_len += (8 - extra); 2623 m0->m_pkthdr.len += (8 - extra); 2624 } else { 2625 /* truncate */ 2626 m0->m_pkthdr.len -= extra; 2627 m0->m_len -= extra; 2628 } 2629 } 2630 len = m0->m_pkthdr.len + sizeof(*nd_opt_rh); 2631 m0->m_pkthdr.len = m0->m_len = len - sizeof(*nd_opt_rh); 2632 } 2633 2634 nd_opt_rh = (struct nd_opt_rd_hdr *)p; 2635 bzero(nd_opt_rh, sizeof(*nd_opt_rh)); 2636 nd_opt_rh->nd_opt_rh_type = ND_OPT_REDIRECTED_HEADER; 2637 nd_opt_rh->nd_opt_rh_len = len >> 3; 2638 p += sizeof(*nd_opt_rh); 2639 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2640 2641 /* connect m0 to m */ 2642 m->m_next = m0; 2643 m->m_pkthdr.len = m->m_len + m0->m_len; 2644 } 2645 noredhdropt:; 2646 2647 if (IN6_IS_ADDR_LINKLOCAL(&sip6->ip6_src)) 2648 sip6->ip6_src.s6_addr16[1] = 0; 2649 if (IN6_IS_ADDR_LINKLOCAL(&sip6->ip6_dst)) 2650 sip6->ip6_dst.s6_addr16[1] = 0; 2651 #if 0 2652 if (IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_src)) 2653 ip6->ip6_src.s6_addr16[1] = 0; 2654 if (IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_dst)) 2655 ip6->ip6_dst.s6_addr16[1] = 0; 2656 #endif 2657 if (IN6_IS_ADDR_LINKLOCAL(&nd_rd->nd_rd_target)) 2658 nd_rd->nd_rd_target.s6_addr16[1] = 0; 2659 if (IN6_IS_ADDR_LINKLOCAL(&nd_rd->nd_rd_dst)) 2660 nd_rd->nd_rd_dst.s6_addr16[1] = 0; 2661 2662 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr)); 2663 2664 nd_rd->nd_rd_cksum = 0; 2665 nd_rd->nd_rd_cksum 2666 = in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), ntohs(ip6->ip6_plen)); 2667 2668 /* send the packet to outside... */ 2669 #ifdef IPSEC 2670 /* Don't lookup socket */ 2671 (void)ipsec_setsocket(m, NULL); 2672 #endif /*IPSEC*/ 2673 ip6_output(m, NULL, NULL, 0, NULL, &outif); 2674 if (outif) { 2675 icmp6_ifstat_inc(outif, ifs6_out_msg); 2676 icmp6_ifstat_inc(outif, ifs6_out_redirect); 2677 } 2678 icmp6stat.icp6s_outhist[ND_REDIRECT]++; 2679 2680 return; 2681 2682 fail: 2683 if (m) 2684 m_freem(m); 2685 if (m0) 2686 m_freem(m0); 2687 } 2688 2689 #ifdef HAVE_NRL_INPCB 2690 #define sotoin6pcb sotoinpcb 2691 #define in6pcb inpcb 2692 #define in6p_icmp6filt inp_icmp6filt 2693 #endif 2694 /* 2695 * ICMPv6 socket option processing. 2696 */ 2697 int 2698 icmp6_ctloutput(so, sopt) 2699 struct socket *so; 2700 struct sockopt *sopt; 2701 { 2702 int error = 0; 2703 int optlen; 2704 struct inpcb *inp = sotoinpcb(so); 2705 int level, op, optname; 2706 2707 if (sopt) { 2708 level = sopt->sopt_level; 2709 op = sopt->sopt_dir; 2710 optname = sopt->sopt_name; 2711 optlen = sopt->sopt_valsize; 2712 } else 2713 level = op = optname = optlen = 0; 2714 2715 if (level != IPPROTO_ICMPV6) { 2716 return EINVAL; 2717 } 2718 2719 switch (op) { 2720 case PRCO_SETOPT: 2721 switch (optname) { 2722 case ICMP6_FILTER: 2723 { 2724 struct icmp6_filter *p; 2725 2726 if (optlen != sizeof(*p)) { 2727 error = EMSGSIZE; 2728 break; 2729 } 2730 if (inp->in6p_icmp6filt == NULL) { 2731 error = EINVAL; 2732 break; 2733 } 2734 error = sooptcopyin(sopt, inp->in6p_icmp6filt, optlen, 2735 optlen); 2736 break; 2737 } 2738 2739 default: 2740 error = ENOPROTOOPT; 2741 break; 2742 } 2743 break; 2744 2745 case PRCO_GETOPT: 2746 switch (optname) { 2747 case ICMP6_FILTER: 2748 { 2749 if (inp->in6p_icmp6filt == NULL) { 2750 error = EINVAL; 2751 break; 2752 } 2753 error = sooptcopyout(sopt, inp->in6p_icmp6filt, 2754 sizeof(struct icmp6_filter)); 2755 break; 2756 } 2757 2758 default: 2759 error = ENOPROTOOPT; 2760 break; 2761 } 2762 break; 2763 } 2764 2765 return(error); 2766 } 2767 #ifdef HAVE_NRL_INPCB 2768 #undef sotoin6pcb 2769 #undef in6pcb 2770 #undef in6p_icmp6filt 2771 #endif 2772 2773 #ifndef HAVE_PPSRATECHECK 2774 #ifndef timersub 2775 #define timersub(tvp, uvp, vvp) \ 2776 do { \ 2777 (vvp)->tv_sec = (tvp)->tv_sec - (uvp)->tv_sec; \ 2778 (vvp)->tv_usec = (tvp)->tv_usec - (uvp)->tv_usec; \ 2779 if ((vvp)->tv_usec < 0) { \ 2780 (vvp)->tv_sec--; \ 2781 (vvp)->tv_usec += 1000000; \ 2782 } \ 2783 } while (0) 2784 #endif 2785 2786 /* 2787 * ppsratecheck(): packets (or events) per second limitation. 2788 */ 2789 static int 2790 ppsratecheck(lasttime, curpps, maxpps) 2791 struct timeval *lasttime; 2792 int *curpps; 2793 int maxpps; /* maximum pps allowed */ 2794 { 2795 struct timeval tv, delta; 2796 int s, rv; 2797 2798 s = splclock(); 2799 microtime(&tv); 2800 splx(s); 2801 2802 timersub(&tv, lasttime, &delta); 2803 2804 /* 2805 * Check for 0,0 so that the message will be seen at least once. 2806 * If more than one second has passed since the last update of 2807 * lasttime, reset the counter. 2808 * 2809 * We do increment *curpps even in *curpps < maxpps case, as some may 2810 * try to use *curpps for stat purposes as well. 2811 */ 2812 if ((lasttime->tv_sec == 0 && lasttime->tv_usec == 0) || 2813 delta.tv_sec >= 1) { 2814 *lasttime = tv; 2815 *curpps = 0; 2816 rv = 1; 2817 } else if (maxpps < 0) 2818 rv = 1; 2819 else if (*curpps < maxpps) 2820 rv = 1; 2821 else 2822 rv = 0; 2823 2824 #if 1 /* DIAGNOSTIC? */ 2825 /* be careful about wrap-around */ 2826 if (*curpps + 1 > *curpps) 2827 *curpps = *curpps + 1; 2828 #else 2829 /* 2830 * assume that there's not too many calls to this function. 2831 * not sure if the assumption holds, as it depends on *caller's* 2832 * behavior, not the behavior of this function. 2833 * IMHO it is wrong to make assumption on the caller's behavior, 2834 * so the above #if is #if 1, not #ifdef DIAGNOSTIC. 2835 */ 2836 *curpps = *curpps + 1; 2837 #endif 2838 2839 return (rv); 2840 } 2841 #endif 2842 2843 /* 2844 * Perform rate limit check. 2845 * Returns 0 if it is okay to send the icmp6 packet. 2846 * Returns 1 if the router SHOULD NOT send this icmp6 packet due to rate 2847 * limitation. 2848 * 2849 * XXX per-destination/type check necessary? 2850 */ 2851 static int 2852 icmp6_ratelimit(dst, type, code) 2853 const struct in6_addr *dst; /* not used at this moment */ 2854 const int type; /* not used at this moment */ 2855 const int code; /* not used at this moment */ 2856 { 2857 int ret; 2858 2859 ret = 0; /* okay to send */ 2860 2861 /* PPS limit */ 2862 if (!ppsratecheck(&icmp6errppslim_last, &icmp6errpps_count, 2863 icmp6errppslim)) { 2864 /* The packet is subject to rate limit */ 2865 ret++; 2866 } 2867 2868 return ret; 2869 } 2870