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 1.2 2003/06/17 04:28:51 dillon 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 <netkey/key.h> 105 #endif 106 107 #ifdef FAST_IPSEC 108 #include <netipsec/ipsec.h> 109 #include <netipsec/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 extern struct domain inet6domain; 145 extern struct ip6protosw inet6sw[]; 146 extern u_char ip6_protox[]; 147 148 struct icmp6stat icmp6stat; 149 150 extern struct inpcbhead ripcb; 151 extern int icmp6errppslim; 152 static int icmp6errpps_count = 0; 153 static struct timeval icmp6errppslim_last; 154 extern int icmp6_nodeinfo; 155 156 static void icmp6_errcount __P((struct icmp6errstat *, int, int)); 157 static int icmp6_rip6_input __P((struct mbuf **, int)); 158 static int icmp6_ratelimit __P((const struct in6_addr *, const int, const int)); 159 static const char *icmp6_redirect_diag __P((struct in6_addr *, 160 struct in6_addr *, struct in6_addr *)); 161 #ifndef HAVE_PPSRATECHECK 162 static int ppsratecheck __P((struct timeval *, int *, int)); 163 #endif 164 static struct mbuf *ni6_input __P((struct mbuf *, int)); 165 static struct mbuf *ni6_nametodns __P((const char *, int, int)); 166 static int ni6_dnsmatch __P((const char *, int, const char *, int)); 167 static int ni6_addrs __P((struct icmp6_nodeinfo *, struct mbuf *, 168 struct ifnet **, char *)); 169 static int ni6_store_addrs __P((struct icmp6_nodeinfo *, struct icmp6_nodeinfo *, 170 struct ifnet *, int)); 171 static int icmp6_notify_error __P((struct mbuf *, int, int, int)); 172 173 #ifdef COMPAT_RFC1885 174 static struct route_in6 icmp6_reflect_rt; 175 #endif 176 177 178 void 179 icmp6_init() 180 { 181 mld6_init(); 182 } 183 184 static void 185 icmp6_errcount(stat, type, code) 186 struct icmp6errstat *stat; 187 int type, code; 188 { 189 switch (type) { 190 case ICMP6_DST_UNREACH: 191 switch (code) { 192 case ICMP6_DST_UNREACH_NOROUTE: 193 stat->icp6errs_dst_unreach_noroute++; 194 return; 195 case ICMP6_DST_UNREACH_ADMIN: 196 stat->icp6errs_dst_unreach_admin++; 197 return; 198 case ICMP6_DST_UNREACH_BEYONDSCOPE: 199 stat->icp6errs_dst_unreach_beyondscope++; 200 return; 201 case ICMP6_DST_UNREACH_ADDR: 202 stat->icp6errs_dst_unreach_addr++; 203 return; 204 case ICMP6_DST_UNREACH_NOPORT: 205 stat->icp6errs_dst_unreach_noport++; 206 return; 207 } 208 break; 209 case ICMP6_PACKET_TOO_BIG: 210 stat->icp6errs_packet_too_big++; 211 return; 212 case ICMP6_TIME_EXCEEDED: 213 switch (code) { 214 case ICMP6_TIME_EXCEED_TRANSIT: 215 stat->icp6errs_time_exceed_transit++; 216 return; 217 case ICMP6_TIME_EXCEED_REASSEMBLY: 218 stat->icp6errs_time_exceed_reassembly++; 219 return; 220 } 221 break; 222 case ICMP6_PARAM_PROB: 223 switch (code) { 224 case ICMP6_PARAMPROB_HEADER: 225 stat->icp6errs_paramprob_header++; 226 return; 227 case ICMP6_PARAMPROB_NEXTHEADER: 228 stat->icp6errs_paramprob_nextheader++; 229 return; 230 case ICMP6_PARAMPROB_OPTION: 231 stat->icp6errs_paramprob_option++; 232 return; 233 } 234 break; 235 case ND_REDIRECT: 236 stat->icp6errs_redirect++; 237 return; 238 } 239 stat->icp6errs_unknown++; 240 } 241 242 /* 243 * Generate an error packet of type error in response to bad IP6 packet. 244 */ 245 void 246 icmp6_error(m, type, code, param) 247 struct mbuf *m; 248 int type, code, param; 249 { 250 struct ip6_hdr *oip6, *nip6; 251 struct icmp6_hdr *icmp6; 252 u_int preplen; 253 int off; 254 int nxt; 255 256 icmp6stat.icp6s_error++; 257 258 /* count per-type-code statistics */ 259 icmp6_errcount(&icmp6stat.icp6s_outerrhist, type, code); 260 261 #ifdef M_DECRYPTED /*not openbsd*/ 262 if (m->m_flags & M_DECRYPTED) { 263 icmp6stat.icp6s_canterror++; 264 goto freeit; 265 } 266 #endif 267 268 #ifndef PULLDOWN_TEST 269 IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), ); 270 #else 271 if (m->m_len < sizeof(struct ip6_hdr)) { 272 m = m_pullup(m, sizeof(struct ip6_hdr)); 273 if (m == NULL) 274 return; 275 } 276 #endif 277 oip6 = mtod(m, struct ip6_hdr *); 278 279 /* 280 * Multicast destination check. For unrecognized option errors, 281 * this check has already done in ip6_unknown_opt(), so we can 282 * check only for other errors. 283 */ 284 if ((m->m_flags & (M_BCAST|M_MCAST) || 285 IN6_IS_ADDR_MULTICAST(&oip6->ip6_dst)) && 286 (type != ICMP6_PACKET_TOO_BIG && 287 (type != ICMP6_PARAM_PROB || 288 code != ICMP6_PARAMPROB_OPTION))) 289 goto freeit; 290 291 /* Source address check. XXX: the case of anycast source? */ 292 if (IN6_IS_ADDR_UNSPECIFIED(&oip6->ip6_src) || 293 IN6_IS_ADDR_MULTICAST(&oip6->ip6_src)) 294 goto freeit; 295 296 /* 297 * If we are about to send ICMPv6 against ICMPv6 error/redirect, 298 * don't do it. 299 */ 300 nxt = -1; 301 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); 302 if (off >= 0 && nxt == IPPROTO_ICMPV6) { 303 struct icmp6_hdr *icp; 304 305 #ifndef PULLDOWN_TEST 306 IP6_EXTHDR_CHECK(m, 0, off + sizeof(struct icmp6_hdr), ); 307 icp = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 308 #else 309 IP6_EXTHDR_GET(icp, struct icmp6_hdr *, m, off, 310 sizeof(*icp)); 311 if (icp == NULL) { 312 icmp6stat.icp6s_tooshort++; 313 return; 314 } 315 #endif 316 if (icp->icmp6_type < ICMP6_ECHO_REQUEST || 317 icp->icmp6_type == ND_REDIRECT) { 318 /* 319 * ICMPv6 error 320 * Special case: for redirect (which is 321 * informational) we must not send icmp6 error. 322 */ 323 icmp6stat.icp6s_canterror++; 324 goto freeit; 325 } else { 326 /* ICMPv6 informational - send the error */ 327 } 328 } else { 329 /* non-ICMPv6 - send the error */ 330 } 331 332 oip6 = mtod(m, struct ip6_hdr *); /* adjust pointer */ 333 334 /* Finally, do rate limitation check. */ 335 if (icmp6_ratelimit(&oip6->ip6_src, type, code)) { 336 icmp6stat.icp6s_toofreq++; 337 goto freeit; 338 } 339 340 /* 341 * OK, ICMP6 can be generated. 342 */ 343 344 if (m->m_pkthdr.len >= ICMPV6_PLD_MAXLEN) 345 m_adj(m, ICMPV6_PLD_MAXLEN - m->m_pkthdr.len); 346 347 preplen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 348 M_PREPEND(m, preplen, M_DONTWAIT); 349 if (m && m->m_len < preplen) 350 m = m_pullup(m, preplen); 351 if (m == NULL) { 352 nd6log((LOG_DEBUG, "ENOBUFS in icmp6_error %d\n", __LINE__)); 353 return; 354 } 355 356 nip6 = mtod(m, struct ip6_hdr *); 357 nip6->ip6_src = oip6->ip6_src; 358 nip6->ip6_dst = oip6->ip6_dst; 359 360 if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_src)) 361 oip6->ip6_src.s6_addr16[1] = 0; 362 if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_dst)) 363 oip6->ip6_dst.s6_addr16[1] = 0; 364 365 icmp6 = (struct icmp6_hdr *)(nip6 + 1); 366 icmp6->icmp6_type = type; 367 icmp6->icmp6_code = code; 368 icmp6->icmp6_pptr = htonl((u_int32_t)param); 369 370 /* 371 * icmp6_reflect() is designed to be in the input path. 372 * icmp6_error() can be called from both input and outut path, 373 * and if we are in output path rcvif could contain bogus value. 374 * clear m->m_pkthdr.rcvif for safety, we should have enough scope 375 * information in ip header (nip6). 376 */ 377 m->m_pkthdr.rcvif = NULL; 378 379 icmp6stat.icp6s_outhist[type]++; 380 icmp6_reflect(m, sizeof(struct ip6_hdr)); /* header order: IPv6 - ICMPv6 */ 381 382 return; 383 384 freeit: 385 /* 386 * If we can't tell wheter or not we can generate ICMP6, free it. 387 */ 388 m_freem(m); 389 } 390 391 /* 392 * Process a received ICMP6 message. 393 */ 394 int 395 icmp6_input(mp, offp, proto) 396 struct mbuf **mp; 397 int *offp, proto; 398 { 399 struct mbuf *m = *mp, *n; 400 struct ip6_hdr *ip6, *nip6; 401 struct icmp6_hdr *icmp6, *nicmp6; 402 int off = *offp; 403 int icmp6len = m->m_pkthdr.len - *offp; 404 int code, sum, noff; 405 406 #ifndef PULLDOWN_TEST 407 IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_hdr), IPPROTO_DONE); 408 /* m might change if M_LOOP. So, call mtod after this */ 409 #endif 410 411 /* 412 * Locate icmp6 structure in mbuf, and check 413 * that not corrupted and of at least minimum length 414 */ 415 416 ip6 = mtod(m, struct ip6_hdr *); 417 if (icmp6len < sizeof(struct icmp6_hdr)) { 418 icmp6stat.icp6s_tooshort++; 419 goto freeit; 420 } 421 422 /* 423 * calculate the checksum 424 */ 425 #ifndef PULLDOWN_TEST 426 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off); 427 #else 428 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 429 if (icmp6 == NULL) { 430 icmp6stat.icp6s_tooshort++; 431 return IPPROTO_DONE; 432 } 433 #endif 434 code = icmp6->icmp6_code; 435 436 if ((sum = in6_cksum(m, IPPROTO_ICMPV6, off, icmp6len)) != 0) { 437 nd6log((LOG_ERR, 438 "ICMP6 checksum error(%d|%x) %s\n", 439 icmp6->icmp6_type, sum, ip6_sprintf(&ip6->ip6_src))); 440 icmp6stat.icp6s_checksum++; 441 goto freeit; 442 } 443 444 if (faithprefix_p != NULL && (*faithprefix_p)(&ip6->ip6_dst)) { 445 /* 446 * Deliver very specific ICMP6 type only. 447 * This is important to deilver TOOBIG. Otherwise PMTUD 448 * will not work. 449 */ 450 switch (icmp6->icmp6_type) { 451 case ICMP6_DST_UNREACH: 452 case ICMP6_PACKET_TOO_BIG: 453 case ICMP6_TIME_EXCEEDED: 454 break; 455 default: 456 goto freeit; 457 } 458 } 459 460 icmp6stat.icp6s_inhist[icmp6->icmp6_type]++; 461 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_msg); 462 if (icmp6->icmp6_type < ICMP6_INFOMSG_MASK) 463 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_error); 464 465 switch (icmp6->icmp6_type) { 466 case ICMP6_DST_UNREACH: 467 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_dstunreach); 468 switch (code) { 469 case ICMP6_DST_UNREACH_NOROUTE: 470 code = PRC_UNREACH_NET; 471 break; 472 case ICMP6_DST_UNREACH_ADMIN: 473 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_adminprohib); 474 code = PRC_UNREACH_PROTOCOL; /* is this a good code? */ 475 break; 476 case ICMP6_DST_UNREACH_ADDR: 477 code = PRC_HOSTDEAD; 478 break; 479 #ifdef COMPAT_RFC1885 480 case ICMP6_DST_UNREACH_NOTNEIGHBOR: 481 code = PRC_UNREACH_SRCFAIL; 482 break; 483 #else 484 case ICMP6_DST_UNREACH_BEYONDSCOPE: 485 /* I mean "source address was incorrect." */ 486 code = PRC_PARAMPROB; 487 break; 488 #endif 489 case ICMP6_DST_UNREACH_NOPORT: 490 code = PRC_UNREACH_PORT; 491 break; 492 default: 493 goto badcode; 494 } 495 goto deliver; 496 break; 497 498 case ICMP6_PACKET_TOO_BIG: 499 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_pkttoobig); 500 if (code != 0) 501 goto badcode; 502 503 code = PRC_MSGSIZE; 504 505 /* 506 * Updating the path MTU will be done after examining 507 * intermediate extension headers. 508 */ 509 goto deliver; 510 break; 511 512 case ICMP6_TIME_EXCEEDED: 513 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_timeexceed); 514 switch (code) { 515 case ICMP6_TIME_EXCEED_TRANSIT: 516 case ICMP6_TIME_EXCEED_REASSEMBLY: 517 code += PRC_TIMXCEED_INTRANS; 518 break; 519 default: 520 goto badcode; 521 } 522 goto deliver; 523 break; 524 525 case ICMP6_PARAM_PROB: 526 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_paramprob); 527 switch (code) { 528 case ICMP6_PARAMPROB_NEXTHEADER: 529 code = PRC_UNREACH_PROTOCOL; 530 break; 531 case ICMP6_PARAMPROB_HEADER: 532 case ICMP6_PARAMPROB_OPTION: 533 code = PRC_PARAMPROB; 534 break; 535 default: 536 goto badcode; 537 } 538 goto deliver; 539 break; 540 541 case ICMP6_ECHO_REQUEST: 542 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echo); 543 if (code != 0) 544 goto badcode; 545 if ((n = m_copy(m, 0, M_COPYALL)) == NULL) { 546 /* Give up remote */ 547 break; 548 } 549 if ((n->m_flags & M_EXT) != 0 550 || n->m_len < off + sizeof(struct icmp6_hdr)) { 551 struct mbuf *n0 = n; 552 const int maxlen = sizeof(*nip6) + sizeof(*nicmp6); 553 int n0len; 554 555 /* 556 * Prepare an internal mbuf. m_pullup() doesn't 557 * always copy the length we specified. 558 */ 559 if (maxlen >= MCLBYTES) { 560 /* Give up remote */ 561 m_freem(n0); 562 break; 563 } 564 MGETHDR(n, M_DONTWAIT, n0->m_type); 565 n0len = n0->m_pkthdr.len; /* save for use below */ 566 if (n) 567 M_MOVE_PKTHDR(n, n0); 568 if (n && maxlen >= MHLEN) { 569 MCLGET(n, M_DONTWAIT); 570 if ((n->m_flags & M_EXT) == 0) { 571 m_free(n); 572 n = NULL; 573 } 574 } 575 if (n == NULL) { 576 /* Give up remote */ 577 m_freem(n0); 578 break; 579 } 580 /* 581 * Copy IPv6 and ICMPv6 only. 582 */ 583 nip6 = mtod(n, struct ip6_hdr *); 584 bcopy(ip6, nip6, sizeof(struct ip6_hdr)); 585 nicmp6 = (struct icmp6_hdr *)(nip6 + 1); 586 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr)); 587 noff = sizeof(struct ip6_hdr); 588 /* new mbuf contains only ipv6+icmpv6 headers */ 589 n->m_len = noff + sizeof(struct icmp6_hdr); 590 /* 591 * Adjust mbuf. ip6_plen will be adjusted in 592 * ip6_output(). 593 */ 594 m_adj(n0, off + sizeof(struct icmp6_hdr)); 595 /* recalculate complete packet size */ 596 n->m_pkthdr.len = n0len + (noff - off); 597 n->m_next = n0; 598 } else { 599 nip6 = mtod(n, struct ip6_hdr *); 600 nicmp6 = (struct icmp6_hdr *)((caddr_t)nip6 + off); 601 noff = off; 602 } 603 nicmp6->icmp6_type = ICMP6_ECHO_REPLY; 604 nicmp6->icmp6_code = 0; 605 if (n) { 606 icmp6stat.icp6s_reflect++; 607 icmp6stat.icp6s_outhist[ICMP6_ECHO_REPLY]++; 608 icmp6_reflect(n, noff); 609 } 610 break; 611 612 case ICMP6_ECHO_REPLY: 613 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echoreply); 614 if (code != 0) 615 goto badcode; 616 break; 617 618 case MLD_LISTENER_QUERY: 619 case MLD_LISTENER_REPORT: 620 if (icmp6len < sizeof(struct mld_hdr)) 621 goto badlen; 622 if (icmp6->icmp6_type == MLD_LISTENER_QUERY) /* XXX: ugly... */ 623 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldquery); 624 else 625 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldreport); 626 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 627 /* give up local */ 628 mld6_input(m, off); 629 m = NULL; 630 goto freeit; 631 } 632 mld6_input(n, off); 633 /* m stays. */ 634 break; 635 636 case MLD_LISTENER_DONE: 637 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mlddone); 638 if (icmp6len < sizeof(struct mld_hdr)) /* necessary? */ 639 goto badlen; 640 break; /* nothing to be done in kernel */ 641 642 case MLD_MTRACE_RESP: 643 case MLD_MTRACE: 644 /* XXX: these two are experimental. not officially defind. */ 645 /* XXX: per-interface statistics? */ 646 break; /* just pass it to applications */ 647 648 case ICMP6_WRUREQUEST: /* ICMP6_FQDN_QUERY */ 649 { 650 enum { WRU, FQDN } mode; 651 652 if (!icmp6_nodeinfo) 653 break; 654 655 if (icmp6len == sizeof(struct icmp6_hdr) + 4) 656 mode = WRU; 657 else if (icmp6len >= sizeof(struct icmp6_nodeinfo)) 658 mode = FQDN; 659 else 660 goto badlen; 661 662 #define hostnamelen strlen(hostname) 663 if (mode == FQDN) { 664 #ifndef PULLDOWN_TEST 665 IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_nodeinfo), 666 IPPROTO_DONE); 667 #endif 668 n = m_copy(m, 0, M_COPYALL); 669 if (n) 670 n = ni6_input(n, off); 671 /* XXX meaningless if n == NULL */ 672 noff = sizeof(struct ip6_hdr); 673 } else { 674 u_char *p; 675 int maxlen, maxhlen; 676 677 if ((icmp6_nodeinfo & 5) != 5) 678 break; 679 680 if (code != 0) 681 goto badcode; 682 maxlen = sizeof(*nip6) + sizeof(*nicmp6) + 4; 683 if (maxlen >= MCLBYTES) { 684 /* Give up remote */ 685 break; 686 } 687 MGETHDR(n, M_DONTWAIT, m->m_type); 688 if (n && maxlen > MHLEN) { 689 MCLGET(n, M_DONTWAIT); 690 if ((n->m_flags & M_EXT) == 0) { 691 m_free(n); 692 n = NULL; 693 } 694 } 695 if (!m_dup_pkthdr(n, m, M_DONTWAIT)) { 696 /* 697 * Previous code did a blind M_COPY_PKTHDR 698 * and said "just for rcvif". If true, then 699 * we could tolerate the dup failing (due to 700 * the deep copy of the tag chain). For now 701 * be conservative and just fail. 702 */ 703 m_free(n); 704 n = NULL; 705 } 706 if (n == NULL) { 707 /* Give up remote */ 708 break; 709 } 710 n->m_pkthdr.rcvif = NULL; 711 n->m_len = 0; 712 maxhlen = M_TRAILINGSPACE(n) - maxlen; 713 if (maxhlen > hostnamelen) 714 maxhlen = hostnamelen; 715 /* 716 * Copy IPv6 and ICMPv6 only. 717 */ 718 nip6 = mtod(n, struct ip6_hdr *); 719 bcopy(ip6, nip6, sizeof(struct ip6_hdr)); 720 nicmp6 = (struct icmp6_hdr *)(nip6 + 1); 721 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr)); 722 p = (u_char *)(nicmp6 + 1); 723 bzero(p, 4); 724 bcopy(hostname, p + 4, maxhlen); /* meaningless TTL */ 725 noff = sizeof(struct ip6_hdr); 726 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) + 727 sizeof(struct icmp6_hdr) + 4 + maxhlen; 728 nicmp6->icmp6_type = ICMP6_WRUREPLY; 729 nicmp6->icmp6_code = 0; 730 } 731 #undef hostnamelen 732 if (n) { 733 icmp6stat.icp6s_reflect++; 734 icmp6stat.icp6s_outhist[ICMP6_WRUREPLY]++; 735 icmp6_reflect(n, noff); 736 } 737 break; 738 } 739 740 case ICMP6_WRUREPLY: 741 if (code != 0) 742 goto badcode; 743 break; 744 745 case ND_ROUTER_SOLICIT: 746 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routersolicit); 747 if (code != 0) 748 goto badcode; 749 if (icmp6len < sizeof(struct nd_router_solicit)) 750 goto badlen; 751 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 752 /* give up local */ 753 nd6_rs_input(m, off, icmp6len); 754 m = NULL; 755 goto freeit; 756 } 757 nd6_rs_input(n, off, icmp6len); 758 /* m stays. */ 759 break; 760 761 case ND_ROUTER_ADVERT: 762 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routeradvert); 763 if (code != 0) 764 goto badcode; 765 if (icmp6len < sizeof(struct nd_router_advert)) 766 goto badlen; 767 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 768 /* give up local */ 769 nd6_ra_input(m, off, icmp6len); 770 m = NULL; 771 goto freeit; 772 } 773 nd6_ra_input(n, off, icmp6len); 774 /* m stays. */ 775 break; 776 777 case ND_NEIGHBOR_SOLICIT: 778 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighborsolicit); 779 if (code != 0) 780 goto badcode; 781 if (icmp6len < sizeof(struct nd_neighbor_solicit)) 782 goto badlen; 783 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 784 /* give up local */ 785 nd6_ns_input(m, off, icmp6len); 786 m = NULL; 787 goto freeit; 788 } 789 nd6_ns_input(n, off, icmp6len); 790 /* m stays. */ 791 break; 792 793 case ND_NEIGHBOR_ADVERT: 794 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighboradvert); 795 if (code != 0) 796 goto badcode; 797 if (icmp6len < sizeof(struct nd_neighbor_advert)) 798 goto badlen; 799 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 800 /* give up local */ 801 nd6_na_input(m, off, icmp6len); 802 m = NULL; 803 goto freeit; 804 } 805 nd6_na_input(n, off, icmp6len); 806 /* m stays. */ 807 break; 808 809 case ND_REDIRECT: 810 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_redirect); 811 if (code != 0) 812 goto badcode; 813 if (icmp6len < sizeof(struct nd_redirect)) 814 goto badlen; 815 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 816 /* give up local */ 817 icmp6_redirect_input(m, off); 818 m = NULL; 819 goto freeit; 820 } 821 icmp6_redirect_input(n, off); 822 /* m stays. */ 823 break; 824 825 case ICMP6_ROUTER_RENUMBERING: 826 if (code != ICMP6_ROUTER_RENUMBERING_COMMAND && 827 code != ICMP6_ROUTER_RENUMBERING_RESULT) 828 goto badcode; 829 if (icmp6len < sizeof(struct icmp6_router_renum)) 830 goto badlen; 831 break; 832 833 default: 834 nd6log((LOG_DEBUG, 835 "icmp6_input: unknown type %d(src=%s, dst=%s, ifid=%d)\n", 836 icmp6->icmp6_type, ip6_sprintf(&ip6->ip6_src), 837 ip6_sprintf(&ip6->ip6_dst), 838 m->m_pkthdr.rcvif ? m->m_pkthdr.rcvif->if_index : 0)); 839 if (icmp6->icmp6_type < ICMP6_ECHO_REQUEST) { 840 /* ICMPv6 error: MUST deliver it by spec... */ 841 code = PRC_NCMDS; 842 /* deliver */ 843 } else { 844 /* ICMPv6 informational: MUST not deliver */ 845 break; 846 } 847 deliver: 848 if (icmp6_notify_error(m, off, icmp6len, code)) { 849 /* In this case, m should've been freed. */ 850 return(IPPROTO_DONE); 851 } 852 break; 853 854 badcode: 855 icmp6stat.icp6s_badcode++; 856 break; 857 858 badlen: 859 icmp6stat.icp6s_badlen++; 860 break; 861 } 862 863 /* deliver the packet to appropriate sockets */ 864 icmp6_rip6_input(&m, *offp); 865 866 return IPPROTO_DONE; 867 868 freeit: 869 m_freem(m); 870 return IPPROTO_DONE; 871 } 872 873 static int 874 icmp6_notify_error(m, off, icmp6len, code) 875 struct mbuf *m; 876 int off, icmp6len; 877 { 878 struct icmp6_hdr *icmp6; 879 struct ip6_hdr *eip6; 880 u_int32_t notifymtu; 881 struct sockaddr_in6 icmp6src, icmp6dst; 882 883 if (icmp6len < sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr)) { 884 icmp6stat.icp6s_tooshort++; 885 goto freeit; 886 } 887 #ifndef PULLDOWN_TEST 888 IP6_EXTHDR_CHECK(m, off, 889 sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr), 890 -1); 891 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 892 #else 893 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, 894 sizeof(*icmp6) + sizeof(struct ip6_hdr)); 895 if (icmp6 == NULL) { 896 icmp6stat.icp6s_tooshort++; 897 return(-1); 898 } 899 #endif 900 eip6 = (struct ip6_hdr *)(icmp6 + 1); 901 902 /* Detect the upper level protocol */ 903 { 904 void (*ctlfunc) __P((int, struct sockaddr *, void *)); 905 u_int8_t nxt = eip6->ip6_nxt; 906 int eoff = off + sizeof(struct icmp6_hdr) + 907 sizeof(struct ip6_hdr); 908 struct ip6ctlparam ip6cp; 909 struct in6_addr *finaldst = NULL; 910 int icmp6type = icmp6->icmp6_type; 911 struct ip6_frag *fh; 912 struct ip6_rthdr *rth; 913 struct ip6_rthdr0 *rth0; 914 int rthlen; 915 916 while (1) { /* XXX: should avoid infinite loop explicitly? */ 917 struct ip6_ext *eh; 918 919 switch (nxt) { 920 case IPPROTO_HOPOPTS: 921 case IPPROTO_DSTOPTS: 922 case IPPROTO_AH: 923 #ifndef PULLDOWN_TEST 924 IP6_EXTHDR_CHECK(m, 0, eoff + 925 sizeof(struct ip6_ext), 926 -1); 927 eh = (struct ip6_ext *)(mtod(m, caddr_t) 928 + eoff); 929 #else 930 IP6_EXTHDR_GET(eh, struct ip6_ext *, m, 931 eoff, sizeof(*eh)); 932 if (eh == NULL) { 933 icmp6stat.icp6s_tooshort++; 934 return(-1); 935 } 936 #endif 937 938 if (nxt == IPPROTO_AH) 939 eoff += (eh->ip6e_len + 2) << 2; 940 else 941 eoff += (eh->ip6e_len + 1) << 3; 942 nxt = eh->ip6e_nxt; 943 break; 944 case IPPROTO_ROUTING: 945 /* 946 * When the erroneous packet contains a 947 * routing header, we should examine the 948 * header to determine the final destination. 949 * Otherwise, we can't properly update 950 * information that depends on the final 951 * destination (e.g. path MTU). 952 */ 953 #ifndef PULLDOWN_TEST 954 IP6_EXTHDR_CHECK(m, 0, eoff + sizeof(*rth), 955 -1); 956 rth = (struct ip6_rthdr *)(mtod(m, caddr_t) 957 + eoff); 958 #else 959 IP6_EXTHDR_GET(rth, struct ip6_rthdr *, m, 960 eoff, sizeof(*rth)); 961 if (rth == NULL) { 962 icmp6stat.icp6s_tooshort++; 963 return(-1); 964 } 965 #endif 966 rthlen = (rth->ip6r_len + 1) << 3; 967 /* 968 * XXX: currently there is no 969 * officially defined type other 970 * than type-0. 971 * Note that if the segment left field 972 * is 0, all intermediate hops must 973 * have been passed. 974 */ 975 if (rth->ip6r_segleft && 976 rth->ip6r_type == IPV6_RTHDR_TYPE_0) { 977 int hops; 978 979 #ifndef PULLDOWN_TEST 980 IP6_EXTHDR_CHECK(m, 0, eoff + rthlen, 981 -1); 982 rth0 = (struct ip6_rthdr0 *)(mtod(m, caddr_t) + eoff); 983 #else 984 IP6_EXTHDR_GET(rth0, 985 struct ip6_rthdr0 *, m, 986 eoff, rthlen); 987 if (rth0 == NULL) { 988 icmp6stat.icp6s_tooshort++; 989 return(-1); 990 } 991 #endif 992 /* just ignore a bogus header */ 993 if ((rth0->ip6r0_len % 2) == 0 && 994 (hops = rth0->ip6r0_len/2)) 995 finaldst = (struct in6_addr *)(rth0 + 1) + (hops - 1); 996 } 997 eoff += rthlen; 998 nxt = rth->ip6r_nxt; 999 break; 1000 case IPPROTO_FRAGMENT: 1001 #ifndef PULLDOWN_TEST 1002 IP6_EXTHDR_CHECK(m, 0, eoff + 1003 sizeof(struct ip6_frag), 1004 -1); 1005 fh = (struct ip6_frag *)(mtod(m, caddr_t) 1006 + eoff); 1007 #else 1008 IP6_EXTHDR_GET(fh, struct ip6_frag *, m, 1009 eoff, sizeof(*fh)); 1010 if (fh == NULL) { 1011 icmp6stat.icp6s_tooshort++; 1012 return(-1); 1013 } 1014 #endif 1015 /* 1016 * Data after a fragment header is meaningless 1017 * unless it is the first fragment, but 1018 * we'll go to the notify label for path MTU 1019 * discovery. 1020 */ 1021 if (fh->ip6f_offlg & IP6F_OFF_MASK) 1022 goto notify; 1023 1024 eoff += sizeof(struct ip6_frag); 1025 nxt = fh->ip6f_nxt; 1026 break; 1027 default: 1028 /* 1029 * This case includes ESP and the No Next 1030 * Header. In such cases going to the notify 1031 * label does not have any meaning 1032 * (i.e. ctlfunc will be NULL), but we go 1033 * anyway since we might have to update 1034 * path MTU information. 1035 */ 1036 goto notify; 1037 } 1038 } 1039 notify: 1040 #ifndef PULLDOWN_TEST 1041 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 1042 #else 1043 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, 1044 sizeof(*icmp6) + sizeof(struct ip6_hdr)); 1045 if (icmp6 == NULL) { 1046 icmp6stat.icp6s_tooshort++; 1047 return(-1); 1048 } 1049 #endif 1050 1051 eip6 = (struct ip6_hdr *)(icmp6 + 1); 1052 bzero(&icmp6dst, sizeof(icmp6dst)); 1053 icmp6dst.sin6_len = sizeof(struct sockaddr_in6); 1054 icmp6dst.sin6_family = AF_INET6; 1055 if (finaldst == NULL) 1056 icmp6dst.sin6_addr = eip6->ip6_dst; 1057 else 1058 icmp6dst.sin6_addr = *finaldst; 1059 icmp6dst.sin6_scope_id = in6_addr2scopeid(m->m_pkthdr.rcvif, 1060 &icmp6dst.sin6_addr); 1061 #ifndef SCOPEDROUTING 1062 if (in6_embedscope(&icmp6dst.sin6_addr, &icmp6dst, 1063 NULL, NULL)) { 1064 /* should be impossbile */ 1065 nd6log((LOG_DEBUG, 1066 "icmp6_notify_error: in6_embedscope failed\n")); 1067 goto freeit; 1068 } 1069 #endif 1070 1071 /* 1072 * retrieve parameters from the inner IPv6 header, and convert 1073 * them into sockaddr structures. 1074 */ 1075 bzero(&icmp6src, sizeof(icmp6src)); 1076 icmp6src.sin6_len = sizeof(struct sockaddr_in6); 1077 icmp6src.sin6_family = AF_INET6; 1078 icmp6src.sin6_addr = eip6->ip6_src; 1079 icmp6src.sin6_scope_id = in6_addr2scopeid(m->m_pkthdr.rcvif, 1080 &icmp6src.sin6_addr); 1081 #ifndef SCOPEDROUTING 1082 if (in6_embedscope(&icmp6src.sin6_addr, &icmp6src, 1083 NULL, NULL)) { 1084 /* should be impossbile */ 1085 nd6log((LOG_DEBUG, 1086 "icmp6_notify_error: in6_embedscope failed\n")); 1087 goto freeit; 1088 } 1089 #endif 1090 icmp6src.sin6_flowinfo = 1091 (eip6->ip6_flow & IPV6_FLOWLABEL_MASK); 1092 1093 if (finaldst == NULL) 1094 finaldst = &eip6->ip6_dst; 1095 ip6cp.ip6c_m = m; 1096 ip6cp.ip6c_icmp6 = icmp6; 1097 ip6cp.ip6c_ip6 = (struct ip6_hdr *)(icmp6 + 1); 1098 ip6cp.ip6c_off = eoff; 1099 ip6cp.ip6c_finaldst = finaldst; 1100 ip6cp.ip6c_src = &icmp6src; 1101 ip6cp.ip6c_nxt = nxt; 1102 1103 if (icmp6type == ICMP6_PACKET_TOO_BIG) { 1104 notifymtu = ntohl(icmp6->icmp6_mtu); 1105 ip6cp.ip6c_cmdarg = (void *)¬ifymtu; 1106 icmp6_mtudisc_update(&ip6cp, 1); /*XXX*/ 1107 } 1108 1109 ctlfunc = (void (*) __P((int, struct sockaddr *, void *))) 1110 (inet6sw[ip6_protox[nxt]].pr_ctlinput); 1111 if (ctlfunc) { 1112 (void) (*ctlfunc)(code, (struct sockaddr *)&icmp6dst, 1113 &ip6cp); 1114 } 1115 } 1116 return(0); 1117 1118 freeit: 1119 m_freem(m); 1120 return(-1); 1121 } 1122 1123 void 1124 icmp6_mtudisc_update(ip6cp, validated) 1125 struct ip6ctlparam *ip6cp; 1126 int validated; 1127 { 1128 struct in6_addr *dst = ip6cp->ip6c_finaldst; 1129 struct icmp6_hdr *icmp6 = ip6cp->ip6c_icmp6; 1130 struct mbuf *m = ip6cp->ip6c_m; /* will be necessary for scope issue */ 1131 u_int mtu = ntohl(icmp6->icmp6_mtu); 1132 struct rtentry *rt = NULL; 1133 struct sockaddr_in6 sin6; 1134 1135 if (!validated) 1136 return; 1137 1138 bzero(&sin6, sizeof(sin6)); 1139 sin6.sin6_family = PF_INET6; 1140 sin6.sin6_len = sizeof(struct sockaddr_in6); 1141 sin6.sin6_addr = *dst; 1142 /* XXX normally, this won't happen */ 1143 if (IN6_IS_ADDR_LINKLOCAL(dst)) { 1144 sin6.sin6_addr.s6_addr16[1] = 1145 htons(m->m_pkthdr.rcvif->if_index); 1146 } 1147 /* sin6.sin6_scope_id = XXX: should be set if DST is a scoped addr */ 1148 rt = rtalloc1((struct sockaddr *)&sin6, 0, 1149 RTF_CLONING | RTF_PRCLONING); 1150 1151 if (rt && (rt->rt_flags & RTF_HOST) 1152 && !(rt->rt_rmx.rmx_locks & RTV_MTU)) { 1153 if (mtu < IPV6_MMTU) { 1154 /* xxx */ 1155 rt->rt_rmx.rmx_locks |= RTV_MTU; 1156 } else if (mtu < rt->rt_ifp->if_mtu && 1157 rt->rt_rmx.rmx_mtu > mtu) { 1158 icmp6stat.icp6s_pmtuchg++; 1159 rt->rt_rmx.rmx_mtu = mtu; 1160 } 1161 } 1162 if (rt) { /* XXX: need braces to avoid conflict with else in RTFREE. */ 1163 RTFREE(rt); 1164 } 1165 } 1166 1167 /* 1168 * Process a Node Information Query packet, based on 1169 * draft-ietf-ipngwg-icmp-name-lookups-07. 1170 * 1171 * Spec incompatibilities: 1172 * - IPv6 Subject address handling 1173 * - IPv4 Subject address handling support missing 1174 * - Proxy reply (answer even if it's not for me) 1175 * - joins NI group address at in6_ifattach() time only, does not cope 1176 * with hostname changes by sethostname(3) 1177 */ 1178 #define hostnamelen strlen(hostname) 1179 static struct mbuf * 1180 ni6_input(m, off) 1181 struct mbuf *m; 1182 int off; 1183 { 1184 struct icmp6_nodeinfo *ni6, *nni6; 1185 struct mbuf *n = NULL; 1186 u_int16_t qtype; 1187 int subjlen; 1188 int replylen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo); 1189 struct ni_reply_fqdn *fqdn; 1190 int addrs; /* for NI_QTYPE_NODEADDR */ 1191 struct ifnet *ifp = NULL; /* for NI_QTYPE_NODEADDR */ 1192 struct sockaddr_in6 sin6; /* double meaning; ip6_dst and subjectaddr */ 1193 struct sockaddr_in6 sin6_d; /* XXX: we should retrieve this from m_aux */ 1194 struct ip6_hdr *ip6; 1195 int oldfqdn = 0; /* if 1, return pascal string (03 draft) */ 1196 char *subj = NULL; 1197 struct in6_ifaddr *ia6 = NULL; 1198 1199 ip6 = mtod(m, struct ip6_hdr *); 1200 #ifndef PULLDOWN_TEST 1201 ni6 = (struct icmp6_nodeinfo *)(mtod(m, caddr_t) + off); 1202 #else 1203 IP6_EXTHDR_GET(ni6, struct icmp6_nodeinfo *, m, off, sizeof(*ni6)); 1204 if (ni6 == NULL) { 1205 /* m is already reclaimed */ 1206 return NULL; 1207 } 1208 #endif 1209 1210 /* 1211 * Validate IPv6 destination address. 1212 * 1213 * The Responder must discard the Query without further processing 1214 * unless it is one of the Responder's unicast or anycast addresses, or 1215 * a link-local scope multicast address which the Responder has joined. 1216 * [icmp-name-lookups-07, Section 4.] 1217 */ 1218 bzero(&sin6, sizeof(sin6)); 1219 sin6.sin6_family = AF_INET6; 1220 sin6.sin6_len = sizeof(struct sockaddr_in6); 1221 bcopy(&ip6->ip6_dst, &sin6.sin6_addr, sizeof(sin6.sin6_addr)); 1222 /* XXX scopeid */ 1223 if ((ia6 = (struct in6_ifaddr *)ifa_ifwithaddr((struct sockaddr *)&sin6)) != NULL) { 1224 /* unicast/anycast, fine */ 1225 if ((ia6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 1226 (icmp6_nodeinfo & 4) == 0) { 1227 nd6log((LOG_DEBUG, "ni6_input: ignore node info to " 1228 "a temporary address in %s:%d", 1229 __FILE__, __LINE__)); 1230 goto bad; 1231 } 1232 } else if (IN6_IS_ADDR_MC_LINKLOCAL(&sin6.sin6_addr)) 1233 ; /* link-local multicast, fine */ 1234 else 1235 goto bad; 1236 1237 /* validate query Subject field. */ 1238 qtype = ntohs(ni6->ni_qtype); 1239 subjlen = m->m_pkthdr.len - off - sizeof(struct icmp6_nodeinfo); 1240 switch (qtype) { 1241 case NI_QTYPE_NOOP: 1242 case NI_QTYPE_SUPTYPES: 1243 /* 07 draft */ 1244 if (ni6->ni_code == ICMP6_NI_SUBJ_FQDN && subjlen == 0) 1245 break; 1246 /* FALLTHROUGH */ 1247 case NI_QTYPE_FQDN: 1248 case NI_QTYPE_NODEADDR: 1249 switch (ni6->ni_code) { 1250 case ICMP6_NI_SUBJ_IPV6: 1251 #if ICMP6_NI_SUBJ_IPV6 != 0 1252 case 0: 1253 #endif 1254 /* 1255 * backward compatibility - try to accept 03 draft 1256 * format, where no Subject is present. 1257 */ 1258 if (qtype == NI_QTYPE_FQDN && ni6->ni_code == 0 && 1259 subjlen == 0) { 1260 oldfqdn++; 1261 break; 1262 } 1263 #if ICMP6_NI_SUBJ_IPV6 != 0 1264 if (ni6->ni_code != ICMP6_NI_SUBJ_IPV6) 1265 goto bad; 1266 #endif 1267 1268 if (subjlen != sizeof(sin6.sin6_addr)) 1269 goto bad; 1270 1271 /* 1272 * Validate Subject address. 1273 * 1274 * Not sure what exactly "address belongs to the node" 1275 * means in the spec, is it just unicast, or what? 1276 * 1277 * At this moment we consider Subject address as 1278 * "belong to the node" if the Subject address equals 1279 * to the IPv6 destination address; validation for 1280 * IPv6 destination address should have done enough 1281 * check for us. 1282 * 1283 * We do not do proxy at this moment. 1284 */ 1285 /* m_pulldown instead of copy? */ 1286 m_copydata(m, off + sizeof(struct icmp6_nodeinfo), 1287 subjlen, (caddr_t)&sin6.sin6_addr); 1288 sin6.sin6_scope_id = in6_addr2scopeid(m->m_pkthdr.rcvif, 1289 &sin6.sin6_addr); 1290 #ifndef SCOPEDROUTING 1291 in6_embedscope(&sin6.sin6_addr, &sin6, NULL, NULL); 1292 #endif 1293 bzero(&sin6_d, sizeof(sin6_d)); 1294 sin6_d.sin6_family = AF_INET6; /* not used, actually */ 1295 sin6_d.sin6_len = sizeof(sin6_d); /* ditto */ 1296 sin6_d.sin6_addr = ip6->ip6_dst; 1297 sin6_d.sin6_scope_id = in6_addr2scopeid(m->m_pkthdr.rcvif, 1298 &ip6->ip6_dst); 1299 #ifndef SCOPEDROUTING 1300 in6_embedscope(&sin6_d.sin6_addr, &sin6_d, NULL, NULL); 1301 #endif 1302 subj = (char *)&sin6; 1303 if (SA6_ARE_ADDR_EQUAL(&sin6, &sin6_d)) 1304 break; 1305 1306 /* 1307 * XXX if we are to allow other cases, we should really 1308 * be careful about scope here. 1309 * basically, we should disallow queries toward IPv6 1310 * destination X with subject Y, if scope(X) > scope(Y). 1311 * if we allow scope(X) > scope(Y), it will result in 1312 * information leakage across scope boundary. 1313 */ 1314 goto bad; 1315 1316 case ICMP6_NI_SUBJ_FQDN: 1317 /* 1318 * Validate Subject name with gethostname(3). 1319 * 1320 * The behavior may need some debate, since: 1321 * - we are not sure if the node has FQDN as 1322 * hostname (returned by gethostname(3)). 1323 * - the code does wildcard match for truncated names. 1324 * however, we are not sure if we want to perform 1325 * wildcard match, if gethostname(3) side has 1326 * truncated hostname. 1327 */ 1328 n = ni6_nametodns(hostname, hostnamelen, 0); 1329 if (!n || n->m_next || n->m_len == 0) 1330 goto bad; 1331 IP6_EXTHDR_GET(subj, char *, m, 1332 off + sizeof(struct icmp6_nodeinfo), subjlen); 1333 if (subj == NULL) 1334 goto bad; 1335 if (!ni6_dnsmatch(subj, subjlen, mtod(n, const char *), 1336 n->m_len)) { 1337 goto bad; 1338 } 1339 m_freem(n); 1340 n = NULL; 1341 break; 1342 1343 case ICMP6_NI_SUBJ_IPV4: /* XXX: to be implemented? */ 1344 default: 1345 goto bad; 1346 } 1347 break; 1348 } 1349 1350 /* refuse based on configuration. XXX ICMP6_NI_REFUSED? */ 1351 switch (qtype) { 1352 case NI_QTYPE_FQDN: 1353 if ((icmp6_nodeinfo & 1) == 0) 1354 goto bad; 1355 break; 1356 case NI_QTYPE_NODEADDR: 1357 if ((icmp6_nodeinfo & 2) == 0) 1358 goto bad; 1359 break; 1360 } 1361 1362 /* guess reply length */ 1363 switch (qtype) { 1364 case NI_QTYPE_NOOP: 1365 break; /* no reply data */ 1366 case NI_QTYPE_SUPTYPES: 1367 replylen += sizeof(u_int32_t); 1368 break; 1369 case NI_QTYPE_FQDN: 1370 /* XXX will append an mbuf */ 1371 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1372 break; 1373 case NI_QTYPE_NODEADDR: 1374 addrs = ni6_addrs(ni6, m, &ifp, subj); 1375 if ((replylen += addrs * (sizeof(struct in6_addr) + 1376 sizeof(u_int32_t))) > MCLBYTES) 1377 replylen = MCLBYTES; /* XXX: will truncate pkt later */ 1378 break; 1379 default: 1380 /* 1381 * XXX: We must return a reply with the ICMP6 code 1382 * `unknown Qtype' in this case. However we regard the case 1383 * as an FQDN query for backward compatibility. 1384 * Older versions set a random value to this field, 1385 * so it rarely varies in the defined qtypes. 1386 * But the mechanism is not reliable... 1387 * maybe we should obsolete older versions. 1388 */ 1389 qtype = NI_QTYPE_FQDN; 1390 /* XXX will append an mbuf */ 1391 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1392 oldfqdn++; 1393 break; 1394 } 1395 1396 /* allocate an mbuf to reply. */ 1397 MGETHDR(n, M_DONTWAIT, m->m_type); 1398 if (n == NULL) { 1399 m_freem(m); 1400 return(NULL); 1401 } 1402 M_MOVE_PKTHDR(n, m); /* just for recvif */ 1403 if (replylen > MHLEN) { 1404 if (replylen > MCLBYTES) { 1405 /* 1406 * XXX: should we try to allocate more? But MCLBYTES 1407 * is probably much larger than IPV6_MMTU... 1408 */ 1409 goto bad; 1410 } 1411 MCLGET(n, M_DONTWAIT); 1412 if ((n->m_flags & M_EXT) == 0) { 1413 goto bad; 1414 } 1415 } 1416 n->m_pkthdr.len = n->m_len = replylen; 1417 1418 /* copy mbuf header and IPv6 + Node Information base headers */ 1419 bcopy(mtod(m, caddr_t), mtod(n, caddr_t), sizeof(struct ip6_hdr)); 1420 nni6 = (struct icmp6_nodeinfo *)(mtod(n, struct ip6_hdr *) + 1); 1421 bcopy((caddr_t)ni6, (caddr_t)nni6, sizeof(struct icmp6_nodeinfo)); 1422 1423 /* qtype dependent procedure */ 1424 switch (qtype) { 1425 case NI_QTYPE_NOOP: 1426 nni6->ni_code = ICMP6_NI_SUCCESS; 1427 nni6->ni_flags = 0; 1428 break; 1429 case NI_QTYPE_SUPTYPES: 1430 { 1431 u_int32_t v; 1432 nni6->ni_code = ICMP6_NI_SUCCESS; 1433 nni6->ni_flags = htons(0x0000); /* raw bitmap */ 1434 /* supports NOOP, SUPTYPES, FQDN, and NODEADDR */ 1435 v = (u_int32_t)htonl(0x0000000f); 1436 bcopy(&v, nni6 + 1, sizeof(u_int32_t)); 1437 break; 1438 } 1439 case NI_QTYPE_FQDN: 1440 nni6->ni_code = ICMP6_NI_SUCCESS; 1441 fqdn = (struct ni_reply_fqdn *)(mtod(n, caddr_t) + 1442 sizeof(struct ip6_hdr) + 1443 sizeof(struct icmp6_nodeinfo)); 1444 nni6->ni_flags = 0; /* XXX: meaningless TTL */ 1445 fqdn->ni_fqdn_ttl = 0; /* ditto. */ 1446 /* 1447 * XXX do we really have FQDN in variable "hostname"? 1448 */ 1449 n->m_next = ni6_nametodns(hostname, hostnamelen, oldfqdn); 1450 if (n->m_next == NULL) 1451 goto bad; 1452 /* XXX we assume that n->m_next is not a chain */ 1453 if (n->m_next->m_next != NULL) 1454 goto bad; 1455 n->m_pkthdr.len += n->m_next->m_len; 1456 break; 1457 case NI_QTYPE_NODEADDR: 1458 { 1459 int lenlim, copied; 1460 1461 nni6->ni_code = ICMP6_NI_SUCCESS; 1462 n->m_pkthdr.len = n->m_len = 1463 sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo); 1464 lenlim = M_TRAILINGSPACE(n); 1465 copied = ni6_store_addrs(ni6, nni6, ifp, lenlim); 1466 /* XXX: reset mbuf length */ 1467 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) + 1468 sizeof(struct icmp6_nodeinfo) + copied; 1469 break; 1470 } 1471 default: 1472 break; /* XXX impossible! */ 1473 } 1474 1475 nni6->ni_type = ICMP6_NI_REPLY; 1476 m_freem(m); 1477 return(n); 1478 1479 bad: 1480 m_freem(m); 1481 if (n) 1482 m_freem(n); 1483 return(NULL); 1484 } 1485 #undef hostnamelen 1486 1487 /* 1488 * make a mbuf with DNS-encoded string. no compression support. 1489 * 1490 * XXX names with less than 2 dots (like "foo" or "foo.section") will be 1491 * treated as truncated name (two \0 at the end). this is a wild guess. 1492 */ 1493 static struct mbuf * 1494 ni6_nametodns(name, namelen, old) 1495 const char *name; 1496 int namelen; 1497 int old; /* return pascal string if non-zero */ 1498 { 1499 struct mbuf *m; 1500 char *cp, *ep; 1501 const char *p, *q; 1502 int i, len, nterm; 1503 1504 if (old) 1505 len = namelen + 1; 1506 else 1507 len = MCLBYTES; 1508 1509 /* because MAXHOSTNAMELEN is usually 256, we use cluster mbuf */ 1510 MGET(m, M_DONTWAIT, MT_DATA); 1511 if (m && len > MLEN) { 1512 MCLGET(m, M_DONTWAIT); 1513 if ((m->m_flags & M_EXT) == 0) 1514 goto fail; 1515 } 1516 if (!m) 1517 goto fail; 1518 m->m_next = NULL; 1519 1520 if (old) { 1521 m->m_len = len; 1522 *mtod(m, char *) = namelen; 1523 bcopy(name, mtod(m, char *) + 1, namelen); 1524 return m; 1525 } else { 1526 m->m_len = 0; 1527 cp = mtod(m, char *); 1528 ep = mtod(m, char *) + M_TRAILINGSPACE(m); 1529 1530 /* if not certain about my name, return empty buffer */ 1531 if (namelen == 0) 1532 return m; 1533 1534 /* 1535 * guess if it looks like shortened hostname, or FQDN. 1536 * shortened hostname needs two trailing "\0". 1537 */ 1538 i = 0; 1539 for (p = name; p < name + namelen; p++) { 1540 if (*p && *p == '.') 1541 i++; 1542 } 1543 if (i < 2) 1544 nterm = 2; 1545 else 1546 nterm = 1; 1547 1548 p = name; 1549 while (cp < ep && p < name + namelen) { 1550 i = 0; 1551 for (q = p; q < name + namelen && *q && *q != '.'; q++) 1552 i++; 1553 /* result does not fit into mbuf */ 1554 if (cp + i + 1 >= ep) 1555 goto fail; 1556 /* 1557 * DNS label length restriction, RFC1035 page 8. 1558 * "i == 0" case is included here to avoid returning 1559 * 0-length label on "foo..bar". 1560 */ 1561 if (i <= 0 || i >= 64) 1562 goto fail; 1563 *cp++ = i; 1564 bcopy(p, cp, i); 1565 cp += i; 1566 p = q; 1567 if (p < name + namelen && *p == '.') 1568 p++; 1569 } 1570 /* termination */ 1571 if (cp + nterm >= ep) 1572 goto fail; 1573 while (nterm-- > 0) 1574 *cp++ = '\0'; 1575 m->m_len = cp - mtod(m, char *); 1576 return m; 1577 } 1578 1579 panic("should not reach here"); 1580 /* NOTREACHED */ 1581 1582 fail: 1583 if (m) 1584 m_freem(m); 1585 return NULL; 1586 } 1587 1588 /* 1589 * check if two DNS-encoded string matches. takes care of truncated 1590 * form (with \0\0 at the end). no compression support. 1591 * XXX upper/lowercase match (see RFC2065) 1592 */ 1593 static int 1594 ni6_dnsmatch(a, alen, b, blen) 1595 const char *a; 1596 int alen; 1597 const char *b; 1598 int blen; 1599 { 1600 const char *a0, *b0; 1601 int l; 1602 1603 /* simplest case - need validation? */ 1604 if (alen == blen && bcmp(a, b, alen) == 0) 1605 return 1; 1606 1607 a0 = a; 1608 b0 = b; 1609 1610 /* termination is mandatory */ 1611 if (alen < 2 || blen < 2) 1612 return 0; 1613 if (a0[alen - 1] != '\0' || b0[blen - 1] != '\0') 1614 return 0; 1615 alen--; 1616 blen--; 1617 1618 while (a - a0 < alen && b - b0 < blen) { 1619 if (a - a0 + 1 > alen || b - b0 + 1 > blen) 1620 return 0; 1621 1622 if ((signed char)a[0] < 0 || (signed char)b[0] < 0) 1623 return 0; 1624 /* we don't support compression yet */ 1625 if (a[0] >= 64 || b[0] >= 64) 1626 return 0; 1627 1628 /* truncated case */ 1629 if (a[0] == 0 && a - a0 == alen - 1) 1630 return 1; 1631 if (b[0] == 0 && b - b0 == blen - 1) 1632 return 1; 1633 if (a[0] == 0 || b[0] == 0) 1634 return 0; 1635 1636 if (a[0] != b[0]) 1637 return 0; 1638 l = a[0]; 1639 if (a - a0 + 1 + l > alen || b - b0 + 1 + l > blen) 1640 return 0; 1641 if (bcmp(a + 1, b + 1, l) != 0) 1642 return 0; 1643 1644 a += 1 + l; 1645 b += 1 + l; 1646 } 1647 1648 if (a - a0 == alen && b - b0 == blen) 1649 return 1; 1650 else 1651 return 0; 1652 } 1653 1654 /* 1655 * calculate the number of addresses to be returned in the node info reply. 1656 */ 1657 static int 1658 ni6_addrs(ni6, m, ifpp, subj) 1659 struct icmp6_nodeinfo *ni6; 1660 struct mbuf *m; 1661 struct ifnet **ifpp; 1662 char *subj; 1663 { 1664 struct ifnet *ifp; 1665 struct in6_ifaddr *ifa6; 1666 struct ifaddr *ifa; 1667 struct sockaddr_in6 *subj_ip6 = NULL; /* XXX pedant */ 1668 int addrs = 0, addrsofif, iffound = 0; 1669 int niflags = ni6->ni_flags; 1670 1671 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0) { 1672 switch (ni6->ni_code) { 1673 case ICMP6_NI_SUBJ_IPV6: 1674 if (subj == NULL) /* must be impossible... */ 1675 return(0); 1676 subj_ip6 = (struct sockaddr_in6 *)subj; 1677 break; 1678 default: 1679 /* 1680 * XXX: we only support IPv6 subject address for 1681 * this Qtype. 1682 */ 1683 return(0); 1684 } 1685 } 1686 1687 for (ifp = TAILQ_FIRST(&ifnet); ifp; ifp = TAILQ_NEXT(ifp, if_list)) 1688 { 1689 addrsofif = 0; 1690 TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list) 1691 { 1692 if (ifa->ifa_addr->sa_family != AF_INET6) 1693 continue; 1694 ifa6 = (struct in6_ifaddr *)ifa; 1695 1696 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0 && 1697 IN6_ARE_ADDR_EQUAL(&subj_ip6->sin6_addr, 1698 &ifa6->ia_addr.sin6_addr)) 1699 iffound = 1; 1700 1701 /* 1702 * IPv4-mapped addresses can only be returned by a 1703 * Node Information proxy, since they represent 1704 * addresses of IPv4-only nodes, which perforce do 1705 * not implement this protocol. 1706 * [icmp-name-lookups-07, Section 5.4] 1707 * So we don't support NI_NODEADDR_FLAG_COMPAT in 1708 * this function at this moment. 1709 */ 1710 1711 /* What do we have to do about ::1? */ 1712 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1713 case IPV6_ADDR_SCOPE_LINKLOCAL: 1714 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0) 1715 continue; 1716 break; 1717 case IPV6_ADDR_SCOPE_SITELOCAL: 1718 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0) 1719 continue; 1720 break; 1721 case IPV6_ADDR_SCOPE_GLOBAL: 1722 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0) 1723 continue; 1724 break; 1725 default: 1726 continue; 1727 } 1728 1729 /* 1730 * check if anycast is okay. 1731 * XXX: just experimental. not in the spec. 1732 */ 1733 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 && 1734 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0) 1735 continue; /* we need only unicast addresses */ 1736 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 1737 (icmp6_nodeinfo & 4) == 0) { 1738 continue; 1739 } 1740 addrsofif++; /* count the address */ 1741 } 1742 if (iffound) { 1743 *ifpp = ifp; 1744 return(addrsofif); 1745 } 1746 1747 addrs += addrsofif; 1748 } 1749 1750 return(addrs); 1751 } 1752 1753 static int 1754 ni6_store_addrs(ni6, nni6, ifp0, resid) 1755 struct icmp6_nodeinfo *ni6, *nni6; 1756 struct ifnet *ifp0; 1757 int resid; 1758 { 1759 struct ifnet *ifp = ifp0 ? ifp0 : TAILQ_FIRST(&ifnet); 1760 struct in6_ifaddr *ifa6; 1761 struct ifaddr *ifa; 1762 struct ifnet *ifp_dep = NULL; 1763 int copied = 0, allow_deprecated = 0; 1764 u_char *cp = (u_char *)(nni6 + 1); 1765 int niflags = ni6->ni_flags; 1766 u_int32_t ltime; 1767 1768 if (ifp0 == NULL && !(niflags & NI_NODEADDR_FLAG_ALL)) 1769 return(0); /* needless to copy */ 1770 1771 again: 1772 1773 for (; ifp; ifp = TAILQ_NEXT(ifp, if_list)) 1774 { 1775 for (ifa = ifp->if_addrlist.tqh_first; ifa; 1776 ifa = ifa->ifa_list.tqe_next) 1777 { 1778 if (ifa->ifa_addr->sa_family != AF_INET6) 1779 continue; 1780 ifa6 = (struct in6_ifaddr *)ifa; 1781 1782 if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) != 0 && 1783 allow_deprecated == 0) { 1784 /* 1785 * prefererred address should be put before 1786 * deprecated addresses. 1787 */ 1788 1789 /* record the interface for later search */ 1790 if (ifp_dep == NULL) 1791 ifp_dep = ifp; 1792 1793 continue; 1794 } 1795 else if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) == 0 && 1796 allow_deprecated != 0) 1797 continue; /* we now collect deprecated addrs */ 1798 1799 /* What do we have to do about ::1? */ 1800 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1801 case IPV6_ADDR_SCOPE_LINKLOCAL: 1802 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0) 1803 continue; 1804 break; 1805 case IPV6_ADDR_SCOPE_SITELOCAL: 1806 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0) 1807 continue; 1808 break; 1809 case IPV6_ADDR_SCOPE_GLOBAL: 1810 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0) 1811 continue; 1812 break; 1813 default: 1814 continue; 1815 } 1816 1817 /* 1818 * check if anycast is okay. 1819 * XXX: just experimental. not in the spec. 1820 */ 1821 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 && 1822 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0) 1823 continue; 1824 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 1825 (icmp6_nodeinfo & 4) == 0) { 1826 continue; 1827 } 1828 1829 /* now we can copy the address */ 1830 if (resid < sizeof(struct in6_addr) + 1831 sizeof(u_int32_t)) { 1832 /* 1833 * We give up much more copy. 1834 * Set the truncate flag and return. 1835 */ 1836 nni6->ni_flags |= 1837 NI_NODEADDR_FLAG_TRUNCATE; 1838 return(copied); 1839 } 1840 1841 /* 1842 * Set the TTL of the address. 1843 * The TTL value should be one of the following 1844 * according to the specification: 1845 * 1846 * 1. The remaining lifetime of a DHCP lease on the 1847 * address, or 1848 * 2. The remaining Valid Lifetime of a prefix from 1849 * which the address was derived through Stateless 1850 * Autoconfiguration. 1851 * 1852 * Note that we currently do not support stateful 1853 * address configuration by DHCPv6, so the former 1854 * case can't happen. 1855 */ 1856 if (ifa6->ia6_lifetime.ia6t_expire == 0) 1857 ltime = ND6_INFINITE_LIFETIME; 1858 else { 1859 if (ifa6->ia6_lifetime.ia6t_expire > 1860 time_second) 1861 ltime = htonl(ifa6->ia6_lifetime.ia6t_expire - time_second); 1862 else 1863 ltime = 0; 1864 } 1865 1866 bcopy(<ime, cp, sizeof(u_int32_t)); 1867 cp += sizeof(u_int32_t); 1868 1869 /* copy the address itself */ 1870 bcopy(&ifa6->ia_addr.sin6_addr, cp, 1871 sizeof(struct in6_addr)); 1872 /* XXX: KAME link-local hack; remove ifindex */ 1873 if (IN6_IS_ADDR_LINKLOCAL(&ifa6->ia_addr.sin6_addr)) 1874 ((struct in6_addr *)cp)->s6_addr16[1] = 0; 1875 cp += sizeof(struct in6_addr); 1876 1877 resid -= (sizeof(struct in6_addr) + sizeof(u_int32_t)); 1878 copied += (sizeof(struct in6_addr) + 1879 sizeof(u_int32_t)); 1880 } 1881 if (ifp0) /* we need search only on the specified IF */ 1882 break; 1883 } 1884 1885 if (allow_deprecated == 0 && ifp_dep != NULL) { 1886 ifp = ifp_dep; 1887 allow_deprecated = 1; 1888 1889 goto again; 1890 } 1891 1892 return(copied); 1893 } 1894 1895 /* 1896 * XXX almost dup'ed code with rip6_input. 1897 */ 1898 static int 1899 icmp6_rip6_input(mp, off) 1900 struct mbuf **mp; 1901 int off; 1902 { 1903 struct mbuf *m = *mp; 1904 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1905 struct in6pcb *in6p; 1906 struct in6pcb *last = NULL; 1907 struct sockaddr_in6 rip6src; 1908 struct icmp6_hdr *icmp6; 1909 struct mbuf *opts = NULL; 1910 1911 #ifndef PULLDOWN_TEST 1912 /* this is assumed to be safe. */ 1913 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off); 1914 #else 1915 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 1916 if (icmp6 == NULL) { 1917 /* m is already reclaimed */ 1918 return IPPROTO_DONE; 1919 } 1920 #endif 1921 1922 bzero(&rip6src, sizeof(rip6src)); 1923 rip6src.sin6_len = sizeof(struct sockaddr_in6); 1924 rip6src.sin6_family = AF_INET6; 1925 /* KAME hack: recover scopeid */ 1926 (void)in6_recoverscope(&rip6src, &ip6->ip6_src, m->m_pkthdr.rcvif); 1927 1928 LIST_FOREACH(in6p, &ripcb, inp_list) 1929 { 1930 if ((in6p->inp_vflag & INP_IPV6) == 0) 1931 continue; 1932 #ifdef HAVE_NRL_INPCB 1933 if (!(in6p->in6p_flags & INP_IPV6)) 1934 continue; 1935 #endif 1936 if (in6p->in6p_ip6_nxt != IPPROTO_ICMPV6) 1937 continue; 1938 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr) && 1939 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr, &ip6->ip6_dst)) 1940 continue; 1941 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr) && 1942 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr, &ip6->ip6_src)) 1943 continue; 1944 if (in6p->in6p_icmp6filt 1945 && ICMP6_FILTER_WILLBLOCK(icmp6->icmp6_type, 1946 in6p->in6p_icmp6filt)) 1947 continue; 1948 if (last) { 1949 struct mbuf *n; 1950 if ((n = m_copy(m, 0, (int)M_COPYALL)) != NULL) { 1951 if (last->in6p_flags & IN6P_CONTROLOPTS) 1952 ip6_savecontrol(last, &opts, ip6, n); 1953 /* strip intermediate headers */ 1954 m_adj(n, off); 1955 if (sbappendaddr(&last->in6p_socket->so_rcv, 1956 (struct sockaddr *)&rip6src, 1957 n, opts) == 0) { 1958 /* should notify about lost packet */ 1959 m_freem(n); 1960 if (opts) { 1961 m_freem(opts); 1962 } 1963 } else 1964 sorwakeup(last->in6p_socket); 1965 opts = NULL; 1966 } 1967 } 1968 last = in6p; 1969 } 1970 if (last) { 1971 if (last->in6p_flags & IN6P_CONTROLOPTS) 1972 ip6_savecontrol(last, &opts, ip6, m); 1973 /* strip intermediate headers */ 1974 m_adj(m, off); 1975 if (sbappendaddr(&last->in6p_socket->so_rcv, 1976 (struct sockaddr *)&rip6src, m, opts) == 0) { 1977 m_freem(m); 1978 if (opts) 1979 m_freem(opts); 1980 } else 1981 sorwakeup(last->in6p_socket); 1982 } else { 1983 m_freem(m); 1984 ip6stat.ip6s_delivered--; 1985 } 1986 return IPPROTO_DONE; 1987 } 1988 1989 /* 1990 * Reflect the ip6 packet back to the source. 1991 * OFF points to the icmp6 header, counted from the top of the mbuf. 1992 */ 1993 void 1994 icmp6_reflect(m, off) 1995 struct mbuf *m; 1996 size_t off; 1997 { 1998 struct ip6_hdr *ip6; 1999 struct icmp6_hdr *icmp6; 2000 struct in6_ifaddr *ia; 2001 struct in6_addr t, *src = 0; 2002 int plen; 2003 int type, code; 2004 struct ifnet *outif = NULL; 2005 struct sockaddr_in6 sa6_src, sa6_dst; 2006 #ifdef COMPAT_RFC1885 2007 int mtu = IPV6_MMTU; 2008 struct sockaddr_in6 *sin6 = &icmp6_reflect_rt.ro_dst; 2009 #endif 2010 2011 /* too short to reflect */ 2012 if (off < sizeof(struct ip6_hdr)) { 2013 nd6log((LOG_DEBUG, 2014 "sanity fail: off=%lx, sizeof(ip6)=%lx in %s:%d\n", 2015 (u_long)off, (u_long)sizeof(struct ip6_hdr), 2016 __FILE__, __LINE__)); 2017 goto bad; 2018 } 2019 2020 /* 2021 * If there are extra headers between IPv6 and ICMPv6, strip 2022 * off that header first. 2023 */ 2024 #ifdef DIAGNOSTIC 2025 if (sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) > MHLEN) 2026 panic("assumption failed in icmp6_reflect"); 2027 #endif 2028 if (off > sizeof(struct ip6_hdr)) { 2029 size_t l; 2030 struct ip6_hdr nip6; 2031 2032 l = off - sizeof(struct ip6_hdr); 2033 m_copydata(m, 0, sizeof(nip6), (caddr_t)&nip6); 2034 m_adj(m, l); 2035 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 2036 if (m->m_len < l) { 2037 if ((m = m_pullup(m, l)) == NULL) 2038 return; 2039 } 2040 bcopy((caddr_t)&nip6, mtod(m, caddr_t), sizeof(nip6)); 2041 } else /* off == sizeof(struct ip6_hdr) */ { 2042 size_t l; 2043 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 2044 if (m->m_len < l) { 2045 if ((m = m_pullup(m, l)) == NULL) 2046 return; 2047 } 2048 } 2049 plen = m->m_pkthdr.len - sizeof(struct ip6_hdr); 2050 ip6 = mtod(m, struct ip6_hdr *); 2051 ip6->ip6_nxt = IPPROTO_ICMPV6; 2052 icmp6 = (struct icmp6_hdr *)(ip6 + 1); 2053 type = icmp6->icmp6_type; /* keep type for statistics */ 2054 code = icmp6->icmp6_code; /* ditto. */ 2055 2056 t = ip6->ip6_dst; 2057 /* 2058 * ip6_input() drops a packet if its src is multicast. 2059 * So, the src is never multicast. 2060 */ 2061 ip6->ip6_dst = ip6->ip6_src; 2062 2063 /* 2064 * XXX: make sure to embed scope zone information, using 2065 * already embedded IDs or the received interface (if any). 2066 * Note that rcvif may be NULL. 2067 * TODO: scoped routing case (XXX). 2068 */ 2069 bzero(&sa6_src, sizeof(sa6_src)); 2070 sa6_src.sin6_family = AF_INET6; 2071 sa6_src.sin6_len = sizeof(sa6_src); 2072 sa6_src.sin6_addr = ip6->ip6_dst; 2073 in6_recoverscope(&sa6_src, &ip6->ip6_dst, m->m_pkthdr.rcvif); 2074 in6_embedscope(&ip6->ip6_dst, &sa6_src, NULL, NULL); 2075 bzero(&sa6_dst, sizeof(sa6_dst)); 2076 sa6_dst.sin6_family = AF_INET6; 2077 sa6_dst.sin6_len = sizeof(sa6_dst); 2078 sa6_dst.sin6_addr = t; 2079 in6_recoverscope(&sa6_dst, &t, m->m_pkthdr.rcvif); 2080 in6_embedscope(&t, &sa6_dst, NULL, NULL); 2081 2082 #ifdef COMPAT_RFC1885 2083 /* 2084 * xxx guess MTU 2085 * RFC 1885 requires that echo reply should be truncated if it 2086 * does not fit in with (return) path MTU, but the description was 2087 * removed in the new spec. 2088 */ 2089 if (icmp6_reflect_rt.ro_rt == 0 || 2090 ! (IN6_ARE_ADDR_EQUAL(&sin6->sin6_addr, &ip6->ip6_dst))) { 2091 if (icmp6_reflect_rt.ro_rt) { 2092 RTFREE(icmp6_reflect_rt.ro_rt); 2093 icmp6_reflect_rt.ro_rt = 0; 2094 } 2095 bzero(sin6, sizeof(*sin6)); 2096 sin6->sin6_family = PF_INET6; 2097 sin6->sin6_len = sizeof(struct sockaddr_in6); 2098 sin6->sin6_addr = ip6->ip6_dst; 2099 2100 rtalloc_ign((struct route *)&icmp6_reflect_rt.ro_rt, 2101 RTF_PRCLONING); 2102 } 2103 2104 if (icmp6_reflect_rt.ro_rt == 0) 2105 goto bad; 2106 2107 if ((icmp6_reflect_rt.ro_rt->rt_flags & RTF_HOST) 2108 && mtu < icmp6_reflect_rt.ro_rt->rt_ifp->if_mtu) 2109 mtu = icmp6_reflect_rt.ro_rt->rt_rmx.rmx_mtu; 2110 2111 if (mtu < m->m_pkthdr.len) { 2112 plen -= (m->m_pkthdr.len - mtu); 2113 m_adj(m, mtu - m->m_pkthdr.len); 2114 } 2115 #endif 2116 /* 2117 * If the incoming packet was addressed directly to us(i.e. unicast), 2118 * use dst as the src for the reply. 2119 * The IN6_IFF_NOTREADY case would be VERY rare, but is possible 2120 * (for example) when we encounter an error while forwarding procedure 2121 * destined to a duplicated address of ours. 2122 */ 2123 for (ia = in6_ifaddr; ia; ia = ia->ia_next) 2124 if (IN6_ARE_ADDR_EQUAL(&t, &ia->ia_addr.sin6_addr) && 2125 (ia->ia6_flags & (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY)) == 0) { 2126 src = &t; 2127 break; 2128 } 2129 if (ia == NULL && IN6_IS_ADDR_LINKLOCAL(&t) && (m->m_flags & M_LOOP)) { 2130 /* 2131 * This is the case if the dst is our link-local address 2132 * and the sender is also ourselves. 2133 */ 2134 src = &t; 2135 } 2136 2137 if (src == 0) { 2138 int e; 2139 struct route_in6 ro; 2140 2141 /* 2142 * This case matches to multicasts, our anycast, or unicasts 2143 * that we do not own. Select a source address based on the 2144 * source address of the erroneous packet. 2145 */ 2146 bzero(&ro, sizeof(ro)); 2147 src = in6_selectsrc(&sa6_src, NULL, NULL, &ro, NULL, &e); 2148 if (ro.ro_rt) 2149 RTFREE(ro.ro_rt); /* XXX: we could use this */ 2150 if (src == NULL) { 2151 nd6log((LOG_DEBUG, 2152 "icmp6_reflect: source can't be determined: " 2153 "dst=%s, error=%d\n", 2154 ip6_sprintf(&sa6_src.sin6_addr), e)); 2155 goto bad; 2156 } 2157 } 2158 2159 ip6->ip6_src = *src; 2160 2161 ip6->ip6_flow = 0; 2162 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2163 ip6->ip6_vfc |= IPV6_VERSION; 2164 ip6->ip6_nxt = IPPROTO_ICMPV6; 2165 if (m->m_pkthdr.rcvif) { 2166 /* XXX: This may not be the outgoing interface */ 2167 ip6->ip6_hlim = nd_ifinfo[m->m_pkthdr.rcvif->if_index].chlim; 2168 } else 2169 ip6->ip6_hlim = ip6_defhlim; 2170 2171 icmp6->icmp6_cksum = 0; 2172 icmp6->icmp6_cksum = in6_cksum(m, IPPROTO_ICMPV6, 2173 sizeof(struct ip6_hdr), plen); 2174 2175 /* 2176 * XXX option handling 2177 */ 2178 2179 m->m_flags &= ~(M_BCAST|M_MCAST); 2180 2181 #ifdef COMPAT_RFC1885 2182 ip6_output(m, NULL, &icmp6_reflect_rt, 0, NULL, &outif, NULL); 2183 #else 2184 ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL); 2185 #endif 2186 if (outif) 2187 icmp6_ifoutstat_inc(outif, type, code); 2188 2189 return; 2190 2191 bad: 2192 m_freem(m); 2193 return; 2194 } 2195 2196 void 2197 icmp6_fasttimo() 2198 { 2199 2200 mld6_fasttimeo(); 2201 } 2202 2203 static const char * 2204 icmp6_redirect_diag(src6, dst6, tgt6) 2205 struct in6_addr *src6; 2206 struct in6_addr *dst6; 2207 struct in6_addr *tgt6; 2208 { 2209 static char buf[1024]; 2210 snprintf(buf, sizeof(buf), "(src=%s dst=%s tgt=%s)", 2211 ip6_sprintf(src6), ip6_sprintf(dst6), ip6_sprintf(tgt6)); 2212 return buf; 2213 } 2214 2215 void 2216 icmp6_redirect_input(m, off) 2217 struct mbuf *m; 2218 int off; 2219 { 2220 struct ifnet *ifp = m->m_pkthdr.rcvif; 2221 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 2222 struct nd_redirect *nd_rd; 2223 int icmp6len = ntohs(ip6->ip6_plen); 2224 char *lladdr = NULL; 2225 int lladdrlen = 0; 2226 u_char *redirhdr = NULL; 2227 int redirhdrlen = 0; 2228 struct rtentry *rt = NULL; 2229 int is_router; 2230 int is_onlink; 2231 struct in6_addr src6 = ip6->ip6_src; 2232 struct in6_addr redtgt6; 2233 struct in6_addr reddst6; 2234 union nd_opts ndopts; 2235 2236 if (!m || !ifp) 2237 return; 2238 2239 /* XXX if we are router, we don't update route by icmp6 redirect */ 2240 if (ip6_forwarding) 2241 goto freeit; 2242 if (!icmp6_rediraccept) 2243 goto freeit; 2244 2245 #ifndef PULLDOWN_TEST 2246 IP6_EXTHDR_CHECK(m, off, icmp6len,); 2247 nd_rd = (struct nd_redirect *)((caddr_t)ip6 + off); 2248 #else 2249 IP6_EXTHDR_GET(nd_rd, struct nd_redirect *, m, off, icmp6len); 2250 if (nd_rd == NULL) { 2251 icmp6stat.icp6s_tooshort++; 2252 return; 2253 } 2254 #endif 2255 redtgt6 = nd_rd->nd_rd_target; 2256 reddst6 = nd_rd->nd_rd_dst; 2257 2258 if (IN6_IS_ADDR_LINKLOCAL(&redtgt6)) 2259 redtgt6.s6_addr16[1] = htons(ifp->if_index); 2260 if (IN6_IS_ADDR_LINKLOCAL(&reddst6)) 2261 reddst6.s6_addr16[1] = htons(ifp->if_index); 2262 2263 /* validation */ 2264 if (!IN6_IS_ADDR_LINKLOCAL(&src6)) { 2265 nd6log((LOG_ERR, 2266 "ICMP6 redirect sent from %s rejected; " 2267 "must be from linklocal\n", ip6_sprintf(&src6))); 2268 goto bad; 2269 } 2270 if (ip6->ip6_hlim != 255) { 2271 nd6log((LOG_ERR, 2272 "ICMP6 redirect sent from %s rejected; " 2273 "hlim=%d (must be 255)\n", 2274 ip6_sprintf(&src6), ip6->ip6_hlim)); 2275 goto bad; 2276 } 2277 { 2278 /* ip6->ip6_src must be equal to gw for icmp6->icmp6_reddst */ 2279 struct sockaddr_in6 sin6; 2280 struct in6_addr *gw6; 2281 2282 bzero(&sin6, sizeof(sin6)); 2283 sin6.sin6_family = AF_INET6; 2284 sin6.sin6_len = sizeof(struct sockaddr_in6); 2285 bcopy(&reddst6, &sin6.sin6_addr, sizeof(reddst6)); 2286 rt = rtalloc1((struct sockaddr *)&sin6, 0, 0UL); 2287 if (rt) { 2288 if (rt->rt_gateway == NULL || 2289 rt->rt_gateway->sa_family != AF_INET6) { 2290 nd6log((LOG_ERR, 2291 "ICMP6 redirect rejected; no route " 2292 "with inet6 gateway found for redirect dst: %s\n", 2293 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2294 RTFREE(rt); 2295 goto bad; 2296 } 2297 2298 gw6 = &(((struct sockaddr_in6 *)rt->rt_gateway)->sin6_addr); 2299 if (bcmp(&src6, gw6, sizeof(struct in6_addr)) != 0) { 2300 nd6log((LOG_ERR, 2301 "ICMP6 redirect rejected; " 2302 "not equal to gw-for-src=%s (must be same): " 2303 "%s\n", 2304 ip6_sprintf(gw6), 2305 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2306 RTFREE(rt); 2307 goto bad; 2308 } 2309 } else { 2310 nd6log((LOG_ERR, 2311 "ICMP6 redirect rejected; " 2312 "no route found for redirect dst: %s\n", 2313 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2314 goto bad; 2315 } 2316 RTFREE(rt); 2317 rt = NULL; 2318 } 2319 if (IN6_IS_ADDR_MULTICAST(&reddst6)) { 2320 nd6log((LOG_ERR, 2321 "ICMP6 redirect rejected; " 2322 "redirect dst must be unicast: %s\n", 2323 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2324 goto bad; 2325 } 2326 2327 is_router = is_onlink = 0; 2328 if (IN6_IS_ADDR_LINKLOCAL(&redtgt6)) 2329 is_router = 1; /* router case */ 2330 if (bcmp(&redtgt6, &reddst6, sizeof(redtgt6)) == 0) 2331 is_onlink = 1; /* on-link destination case */ 2332 if (!is_router && !is_onlink) { 2333 nd6log((LOG_ERR, 2334 "ICMP6 redirect rejected; " 2335 "neither router case nor onlink case: %s\n", 2336 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2337 goto bad; 2338 } 2339 /* validation passed */ 2340 2341 icmp6len -= sizeof(*nd_rd); 2342 nd6_option_init(nd_rd + 1, icmp6len, &ndopts); 2343 if (nd6_options(&ndopts) < 0) { 2344 nd6log((LOG_INFO, "icmp6_redirect_input: " 2345 "invalid ND option, rejected: %s\n", 2346 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2347 /* nd6_options have incremented stats */ 2348 goto freeit; 2349 } 2350 2351 if (ndopts.nd_opts_tgt_lladdr) { 2352 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 2353 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 2354 } 2355 2356 if (ndopts.nd_opts_rh) { 2357 redirhdrlen = ndopts.nd_opts_rh->nd_opt_rh_len; 2358 redirhdr = (u_char *)(ndopts.nd_opts_rh + 1); /* xxx */ 2359 } 2360 2361 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 2362 nd6log((LOG_INFO, 2363 "icmp6_redirect_input: lladdrlen mismatch for %s " 2364 "(if %d, icmp6 packet %d): %s\n", 2365 ip6_sprintf(&redtgt6), ifp->if_addrlen, lladdrlen - 2, 2366 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2367 goto bad; 2368 } 2369 2370 /* RFC 2461 8.3 */ 2371 nd6_cache_lladdr(ifp, &redtgt6, lladdr, lladdrlen, ND_REDIRECT, 2372 is_onlink ? ND_REDIRECT_ONLINK : ND_REDIRECT_ROUTER); 2373 2374 if (!is_onlink) { /* better router case. perform rtredirect. */ 2375 /* perform rtredirect */ 2376 struct sockaddr_in6 sdst; 2377 struct sockaddr_in6 sgw; 2378 struct sockaddr_in6 ssrc; 2379 2380 bzero(&sdst, sizeof(sdst)); 2381 bzero(&sgw, sizeof(sgw)); 2382 bzero(&ssrc, sizeof(ssrc)); 2383 sdst.sin6_family = sgw.sin6_family = ssrc.sin6_family = AF_INET6; 2384 sdst.sin6_len = sgw.sin6_len = ssrc.sin6_len = 2385 sizeof(struct sockaddr_in6); 2386 bcopy(&redtgt6, &sgw.sin6_addr, sizeof(struct in6_addr)); 2387 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2388 bcopy(&src6, &ssrc.sin6_addr, sizeof(struct in6_addr)); 2389 rtredirect((struct sockaddr *)&sdst, (struct sockaddr *)&sgw, 2390 (struct sockaddr *)NULL, RTF_GATEWAY | RTF_HOST, 2391 (struct sockaddr *)&ssrc, 2392 (struct rtentry **)NULL); 2393 } 2394 /* finally update cached route in each socket via pfctlinput */ 2395 { 2396 struct sockaddr_in6 sdst; 2397 2398 bzero(&sdst, sizeof(sdst)); 2399 sdst.sin6_family = AF_INET6; 2400 sdst.sin6_len = sizeof(struct sockaddr_in6); 2401 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2402 pfctlinput(PRC_REDIRECT_HOST, (struct sockaddr *)&sdst); 2403 #ifdef IPSEC 2404 key_sa_routechange((struct sockaddr *)&sdst); 2405 #endif 2406 } 2407 2408 freeit: 2409 m_freem(m); 2410 return; 2411 2412 bad: 2413 icmp6stat.icp6s_badredirect++; 2414 m_freem(m); 2415 } 2416 2417 void 2418 icmp6_redirect_output(m0, rt) 2419 struct mbuf *m0; 2420 struct rtentry *rt; 2421 { 2422 struct ifnet *ifp; /* my outgoing interface */ 2423 struct in6_addr *ifp_ll6; 2424 struct in6_addr *router_ll6; 2425 struct ip6_hdr *sip6; /* m0 as struct ip6_hdr */ 2426 struct mbuf *m = NULL; /* newly allocated one */ 2427 struct ip6_hdr *ip6; /* m as struct ip6_hdr */ 2428 struct nd_redirect *nd_rd; 2429 size_t maxlen; 2430 u_char *p; 2431 struct ifnet *outif = NULL; 2432 struct sockaddr_in6 src_sa; 2433 2434 icmp6_errcount(&icmp6stat.icp6s_outerrhist, ND_REDIRECT, 0); 2435 2436 /* if we are not router, we don't send icmp6 redirect */ 2437 if (!ip6_forwarding || ip6_accept_rtadv) 2438 goto fail; 2439 2440 /* sanity check */ 2441 if (!m0 || !rt || !(rt->rt_flags & RTF_UP) || !(ifp = rt->rt_ifp)) 2442 goto fail; 2443 2444 /* 2445 * Address check: 2446 * the source address must identify a neighbor, and 2447 * the destination address must not be a multicast address 2448 * [RFC 2461, sec 8.2] 2449 */ 2450 sip6 = mtod(m0, struct ip6_hdr *); 2451 bzero(&src_sa, sizeof(src_sa)); 2452 src_sa.sin6_family = AF_INET6; 2453 src_sa.sin6_len = sizeof(src_sa); 2454 src_sa.sin6_addr = sip6->ip6_src; 2455 /* we don't currently use sin6_scope_id, but eventually use it */ 2456 src_sa.sin6_scope_id = in6_addr2scopeid(ifp, &sip6->ip6_src); 2457 if (nd6_is_addr_neighbor(&src_sa, ifp) == 0) 2458 goto fail; 2459 if (IN6_IS_ADDR_MULTICAST(&sip6->ip6_dst)) 2460 goto fail; /* what should we do here? */ 2461 2462 /* rate limit */ 2463 if (icmp6_ratelimit(&sip6->ip6_src, ND_REDIRECT, 0)) 2464 goto fail; 2465 2466 /* 2467 * Since we are going to append up to 1280 bytes (= IPV6_MMTU), 2468 * we almost always ask for an mbuf cluster for simplicity. 2469 * (MHLEN < IPV6_MMTU is almost always true) 2470 */ 2471 #if IPV6_MMTU >= MCLBYTES 2472 # error assumption failed about IPV6_MMTU and MCLBYTES 2473 #endif 2474 MGETHDR(m, M_DONTWAIT, MT_HEADER); 2475 if (m && IPV6_MMTU >= MHLEN) 2476 MCLGET(m, M_DONTWAIT); 2477 if (!m) 2478 goto fail; 2479 m->m_pkthdr.rcvif = NULL; 2480 m->m_len = 0; 2481 maxlen = M_TRAILINGSPACE(m); 2482 maxlen = min(IPV6_MMTU, maxlen); 2483 /* just for safety */ 2484 if (maxlen < sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) + 2485 ((sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7)) { 2486 goto fail; 2487 } 2488 2489 { 2490 /* get ip6 linklocal address for ifp(my outgoing interface). */ 2491 struct in6_ifaddr *ia; 2492 if ((ia = in6ifa_ifpforlinklocal(ifp, 2493 IN6_IFF_NOTREADY| 2494 IN6_IFF_ANYCAST)) == NULL) 2495 goto fail; 2496 ifp_ll6 = &ia->ia_addr.sin6_addr; 2497 } 2498 2499 /* get ip6 linklocal address for the router. */ 2500 if (rt->rt_gateway && (rt->rt_flags & RTF_GATEWAY)) { 2501 struct sockaddr_in6 *sin6; 2502 sin6 = (struct sockaddr_in6 *)rt->rt_gateway; 2503 router_ll6 = &sin6->sin6_addr; 2504 if (!IN6_IS_ADDR_LINKLOCAL(router_ll6)) 2505 router_ll6 = (struct in6_addr *)NULL; 2506 } else 2507 router_ll6 = (struct in6_addr *)NULL; 2508 2509 /* ip6 */ 2510 ip6 = mtod(m, struct ip6_hdr *); 2511 ip6->ip6_flow = 0; 2512 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2513 ip6->ip6_vfc |= IPV6_VERSION; 2514 /* ip6->ip6_plen will be set later */ 2515 ip6->ip6_nxt = IPPROTO_ICMPV6; 2516 ip6->ip6_hlim = 255; 2517 /* ip6->ip6_src must be linklocal addr for my outgoing if. */ 2518 bcopy(ifp_ll6, &ip6->ip6_src, sizeof(struct in6_addr)); 2519 bcopy(&sip6->ip6_src, &ip6->ip6_dst, sizeof(struct in6_addr)); 2520 2521 /* ND Redirect */ 2522 nd_rd = (struct nd_redirect *)(ip6 + 1); 2523 nd_rd->nd_rd_type = ND_REDIRECT; 2524 nd_rd->nd_rd_code = 0; 2525 nd_rd->nd_rd_reserved = 0; 2526 if (rt->rt_flags & RTF_GATEWAY) { 2527 /* 2528 * nd_rd->nd_rd_target must be a link-local address in 2529 * better router cases. 2530 */ 2531 if (!router_ll6) 2532 goto fail; 2533 bcopy(router_ll6, &nd_rd->nd_rd_target, 2534 sizeof(nd_rd->nd_rd_target)); 2535 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2536 sizeof(nd_rd->nd_rd_dst)); 2537 } else { 2538 /* make sure redtgt == reddst */ 2539 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_target, 2540 sizeof(nd_rd->nd_rd_target)); 2541 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2542 sizeof(nd_rd->nd_rd_dst)); 2543 } 2544 2545 p = (u_char *)(nd_rd + 1); 2546 2547 if (!router_ll6) 2548 goto nolladdropt; 2549 2550 { 2551 /* target lladdr option */ 2552 struct rtentry *rt_router = NULL; 2553 int len; 2554 struct sockaddr_dl *sdl; 2555 struct nd_opt_hdr *nd_opt; 2556 char *lladdr; 2557 2558 rt_router = nd6_lookup(router_ll6, 0, ifp); 2559 if (!rt_router) 2560 goto nolladdropt; 2561 len = sizeof(*nd_opt) + ifp->if_addrlen; 2562 len = (len + 7) & ~7; /* round by 8 */ 2563 /* safety check */ 2564 if (len + (p - (u_char *)ip6) > maxlen) 2565 goto nolladdropt; 2566 if (!(rt_router->rt_flags & RTF_GATEWAY) && 2567 (rt_router->rt_flags & RTF_LLINFO) && 2568 (rt_router->rt_gateway->sa_family == AF_LINK) && 2569 (sdl = (struct sockaddr_dl *)rt_router->rt_gateway) && 2570 sdl->sdl_alen) { 2571 nd_opt = (struct nd_opt_hdr *)p; 2572 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 2573 nd_opt->nd_opt_len = len >> 3; 2574 lladdr = (char *)(nd_opt + 1); 2575 bcopy(LLADDR(sdl), lladdr, ifp->if_addrlen); 2576 p += len; 2577 } 2578 } 2579 nolladdropt:; 2580 2581 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2582 2583 /* just to be safe */ 2584 #ifdef M_DECRYPTED /*not openbsd*/ 2585 if (m0->m_flags & M_DECRYPTED) 2586 goto noredhdropt; 2587 #endif 2588 if (p - (u_char *)ip6 > maxlen) 2589 goto noredhdropt; 2590 2591 { 2592 /* redirected header option */ 2593 int len; 2594 struct nd_opt_rd_hdr *nd_opt_rh; 2595 2596 /* 2597 * compute the maximum size for icmp6 redirect header option. 2598 * XXX room for auth header? 2599 */ 2600 len = maxlen - (p - (u_char *)ip6); 2601 len &= ~7; 2602 2603 /* This is just for simplicity. */ 2604 if (m0->m_pkthdr.len != m0->m_len) { 2605 if (m0->m_next) { 2606 m_freem(m0->m_next); 2607 m0->m_next = NULL; 2608 } 2609 m0->m_pkthdr.len = m0->m_len; 2610 } 2611 2612 /* 2613 * Redirected header option spec (RFC2461 4.6.3) talks nothing 2614 * about padding/truncate rule for the original IP packet. 2615 * From the discussion on IPv6imp in Feb 1999, the consensus was: 2616 * - "attach as much as possible" is the goal 2617 * - pad if not aligned (original size can be guessed by original 2618 * ip6 header) 2619 * Following code adds the padding if it is simple enough, 2620 * and truncates if not. 2621 */ 2622 if (m0->m_next || m0->m_pkthdr.len != m0->m_len) 2623 panic("assumption failed in %s:%d", __FILE__, __LINE__); 2624 2625 if (len - sizeof(*nd_opt_rh) < m0->m_pkthdr.len) { 2626 /* not enough room, truncate */ 2627 m0->m_pkthdr.len = m0->m_len = len - sizeof(*nd_opt_rh); 2628 } else { 2629 /* enough room, pad or truncate */ 2630 size_t extra; 2631 2632 extra = m0->m_pkthdr.len % 8; 2633 if (extra) { 2634 /* pad if easy enough, truncate if not */ 2635 if (8 - extra <= M_TRAILINGSPACE(m0)) { 2636 /* pad */ 2637 m0->m_len += (8 - extra); 2638 m0->m_pkthdr.len += (8 - extra); 2639 } else { 2640 /* truncate */ 2641 m0->m_pkthdr.len -= extra; 2642 m0->m_len -= extra; 2643 } 2644 } 2645 len = m0->m_pkthdr.len + sizeof(*nd_opt_rh); 2646 m0->m_pkthdr.len = m0->m_len = len - sizeof(*nd_opt_rh); 2647 } 2648 2649 nd_opt_rh = (struct nd_opt_rd_hdr *)p; 2650 bzero(nd_opt_rh, sizeof(*nd_opt_rh)); 2651 nd_opt_rh->nd_opt_rh_type = ND_OPT_REDIRECTED_HEADER; 2652 nd_opt_rh->nd_opt_rh_len = len >> 3; 2653 p += sizeof(*nd_opt_rh); 2654 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2655 2656 /* connect m0 to m */ 2657 m->m_next = m0; 2658 m->m_pkthdr.len = m->m_len + m0->m_len; 2659 } 2660 noredhdropt:; 2661 2662 if (IN6_IS_ADDR_LINKLOCAL(&sip6->ip6_src)) 2663 sip6->ip6_src.s6_addr16[1] = 0; 2664 if (IN6_IS_ADDR_LINKLOCAL(&sip6->ip6_dst)) 2665 sip6->ip6_dst.s6_addr16[1] = 0; 2666 #if 0 2667 if (IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_src)) 2668 ip6->ip6_src.s6_addr16[1] = 0; 2669 if (IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_dst)) 2670 ip6->ip6_dst.s6_addr16[1] = 0; 2671 #endif 2672 if (IN6_IS_ADDR_LINKLOCAL(&nd_rd->nd_rd_target)) 2673 nd_rd->nd_rd_target.s6_addr16[1] = 0; 2674 if (IN6_IS_ADDR_LINKLOCAL(&nd_rd->nd_rd_dst)) 2675 nd_rd->nd_rd_dst.s6_addr16[1] = 0; 2676 2677 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr)); 2678 2679 nd_rd->nd_rd_cksum = 0; 2680 nd_rd->nd_rd_cksum 2681 = in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), ntohs(ip6->ip6_plen)); 2682 2683 /* send the packet to outside... */ 2684 ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL); 2685 if (outif) { 2686 icmp6_ifstat_inc(outif, ifs6_out_msg); 2687 icmp6_ifstat_inc(outif, ifs6_out_redirect); 2688 } 2689 icmp6stat.icp6s_outhist[ND_REDIRECT]++; 2690 2691 return; 2692 2693 fail: 2694 if (m) 2695 m_freem(m); 2696 if (m0) 2697 m_freem(m0); 2698 } 2699 2700 #ifdef HAVE_NRL_INPCB 2701 #define sotoin6pcb sotoinpcb 2702 #define in6pcb inpcb 2703 #define in6p_icmp6filt inp_icmp6filt 2704 #endif 2705 /* 2706 * ICMPv6 socket option processing. 2707 */ 2708 int 2709 icmp6_ctloutput(so, sopt) 2710 struct socket *so; 2711 struct sockopt *sopt; 2712 { 2713 int error = 0; 2714 int optlen; 2715 struct inpcb *inp = sotoinpcb(so); 2716 int level, op, optname; 2717 2718 if (sopt) { 2719 level = sopt->sopt_level; 2720 op = sopt->sopt_dir; 2721 optname = sopt->sopt_name; 2722 optlen = sopt->sopt_valsize; 2723 } else 2724 level = op = optname = optlen = 0; 2725 2726 if (level != IPPROTO_ICMPV6) { 2727 return EINVAL; 2728 } 2729 2730 switch (op) { 2731 case PRCO_SETOPT: 2732 switch (optname) { 2733 case ICMP6_FILTER: 2734 { 2735 struct icmp6_filter *p; 2736 2737 if (optlen != sizeof(*p)) { 2738 error = EMSGSIZE; 2739 break; 2740 } 2741 if (inp->in6p_icmp6filt == NULL) { 2742 error = EINVAL; 2743 break; 2744 } 2745 error = sooptcopyin(sopt, inp->in6p_icmp6filt, optlen, 2746 optlen); 2747 break; 2748 } 2749 2750 default: 2751 error = ENOPROTOOPT; 2752 break; 2753 } 2754 break; 2755 2756 case PRCO_GETOPT: 2757 switch (optname) { 2758 case ICMP6_FILTER: 2759 { 2760 if (inp->in6p_icmp6filt == NULL) { 2761 error = EINVAL; 2762 break; 2763 } 2764 error = sooptcopyout(sopt, inp->in6p_icmp6filt, 2765 sizeof(struct icmp6_filter)); 2766 break; 2767 } 2768 2769 default: 2770 error = ENOPROTOOPT; 2771 break; 2772 } 2773 break; 2774 } 2775 2776 return(error); 2777 } 2778 #ifdef HAVE_NRL_INPCB 2779 #undef sotoin6pcb 2780 #undef in6pcb 2781 #undef in6p_icmp6filt 2782 #endif 2783 2784 #ifndef HAVE_PPSRATECHECK 2785 #ifndef timersub 2786 #define timersub(tvp, uvp, vvp) \ 2787 do { \ 2788 (vvp)->tv_sec = (tvp)->tv_sec - (uvp)->tv_sec; \ 2789 (vvp)->tv_usec = (tvp)->tv_usec - (uvp)->tv_usec; \ 2790 if ((vvp)->tv_usec < 0) { \ 2791 (vvp)->tv_sec--; \ 2792 (vvp)->tv_usec += 1000000; \ 2793 } \ 2794 } while (0) 2795 #endif 2796 2797 /* 2798 * ppsratecheck(): packets (or events) per second limitation. 2799 */ 2800 static int 2801 ppsratecheck(lasttime, curpps, maxpps) 2802 struct timeval *lasttime; 2803 int *curpps; 2804 int maxpps; /* maximum pps allowed */ 2805 { 2806 struct timeval tv, delta; 2807 int s, rv; 2808 2809 s = splclock(); 2810 microtime(&tv); 2811 splx(s); 2812 2813 timersub(&tv, lasttime, &delta); 2814 2815 /* 2816 * Check for 0,0 so that the message will be seen at least once. 2817 * If more than one second has passed since the last update of 2818 * lasttime, reset the counter. 2819 * 2820 * We do increment *curpps even in *curpps < maxpps case, as some may 2821 * try to use *curpps for stat purposes as well. 2822 */ 2823 if ((lasttime->tv_sec == 0 && lasttime->tv_usec == 0) || 2824 delta.tv_sec >= 1) { 2825 *lasttime = tv; 2826 *curpps = 0; 2827 rv = 1; 2828 } else if (maxpps < 0) 2829 rv = 1; 2830 else if (*curpps < maxpps) 2831 rv = 1; 2832 else 2833 rv = 0; 2834 2835 #if 1 /* DIAGNOSTIC? */ 2836 /* be careful about wrap-around */ 2837 if (*curpps + 1 > *curpps) 2838 *curpps = *curpps + 1; 2839 #else 2840 /* 2841 * assume that there's not too many calls to this function. 2842 * not sure if the assumption holds, as it depends on *caller's* 2843 * behavior, not the behavior of this function. 2844 * IMHO it is wrong to make assumption on the caller's behavior, 2845 * so the above #if is #if 1, not #ifdef DIAGNOSTIC. 2846 */ 2847 *curpps = *curpps + 1; 2848 #endif 2849 2850 return (rv); 2851 } 2852 #endif 2853 2854 /* 2855 * Perform rate limit check. 2856 * Returns 0 if it is okay to send the icmp6 packet. 2857 * Returns 1 if the router SHOULD NOT send this icmp6 packet due to rate 2858 * limitation. 2859 * 2860 * XXX per-destination/type check necessary? 2861 */ 2862 static int 2863 icmp6_ratelimit(dst, type, code) 2864 const struct in6_addr *dst; /* not used at this moment */ 2865 const int type; /* not used at this moment */ 2866 const int code; /* not used at this moment */ 2867 { 2868 int ret; 2869 2870 ret = 0; /* okay to send */ 2871 2872 /* PPS limit */ 2873 if (!ppsratecheck(&icmp6errppslim_last, &icmp6errpps_count, 2874 icmp6errppslim)) { 2875 /* The packet is subject to rate limit */ 2876 ret++; 2877 } 2878 2879 return ret; 2880 } 2881