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 1.27 2008/03/07 11:34:21 sephe Exp $ */ 3 /* $KAME: icmp6.c,v 1.211 2001/04/04 05:56:20 itojun Exp $ */ 4 5 /* 6 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 7 * All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. Neither the name of the project nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 /* 35 * Copyright (c) 1982, 1986, 1988, 1993 36 * The Regents of the University of California. All rights reserved. 37 * 38 * Redistribution and use in source and binary forms, with or without 39 * modification, are permitted provided that the following conditions 40 * are met: 41 * 1. Redistributions of source code must retain the above copyright 42 * notice, this list of conditions and the following disclaimer. 43 * 2. Redistributions in binary form must reproduce the above copyright 44 * notice, this list of conditions and the following disclaimer in the 45 * documentation and/or other materials provided with the distribution. 46 * 3. All advertising materials mentioning features or use of this software 47 * must display the following acknowledgement: 48 * This product includes software developed by the University of 49 * California, Berkeley and its contributors. 50 * 4. Neither the name of the University nor the names of its contributors 51 * may be used to endorse or promote products derived from this software 52 * without specific prior written permission. 53 * 54 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 55 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 56 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 57 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 58 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 59 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 60 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 61 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 62 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 63 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 64 * SUCH DAMAGE. 65 * 66 * @(#)ip_icmp.c 8.2 (Berkeley) 1/4/94 67 */ 68 69 #include "opt_inet.h" 70 #include "opt_inet6.h" 71 #include "opt_ipsec.h" 72 73 #include <sys/param.h> 74 #include <sys/systm.h> 75 #include <sys/malloc.h> 76 #include <sys/mbuf.h> 77 #include <sys/protosw.h> 78 #include <sys/socket.h> 79 #include <sys/socketvar.h> 80 #include <sys/time.h> 81 #include <sys/kernel.h> 82 #include <sys/syslog.h> 83 #include <sys/domain.h> 84 85 #include <net/if.h> 86 #include <net/route.h> 87 #include <net/if_dl.h> 88 #include <net/if_types.h> 89 90 #include <netinet/in.h> 91 #include <netinet/in_var.h> 92 #include <netinet/ip6.h> 93 #include <netinet6/ip6_var.h> 94 #include <netinet/icmp6.h> 95 #include <netinet6/mld6_var.h> 96 #include <netinet/in_pcb.h> 97 #include <netinet6/in6_pcb.h> 98 #include <netinet6/nd6.h> 99 #include <netinet6/in6_ifattach.h> 100 #include <netinet6/ip6protosw.h> 101 102 #ifdef IPSEC 103 #include <netinet6/ipsec.h> 104 #include <netproto/key/key.h> 105 #endif 106 107 #ifdef FAST_IPSEC 108 #include <netproto/ipsec/ipsec.h> 109 #include <netproto/ipsec/key.h> 110 #define IPSEC 111 #endif 112 113 #include <net/net_osdep.h> 114 115 #ifdef HAVE_NRL_INPCB 116 /* inpcb members */ 117 #define in6pcb inpcb 118 #define in6p_laddr inp_laddr6 119 #define in6p_faddr inp_faddr6 120 #define in6p_icmp6filt inp_icmp6filt 121 #define in6p_route inp_route 122 #define in6p_socket inp_socket 123 #define in6p_flags inp_flags 124 #define in6p_moptions inp_moptions6 125 #define in6p_outputopts inp_outputopts6 126 #define in6p_ip6 inp_ipv6 127 #define in6p_flowinfo inp_flowinfo 128 #define in6p_sp inp_sp 129 #define in6p_next inp_next 130 #define in6p_prev inp_prev 131 /* function names */ 132 #define in6_pcbdetach in_pcbdetach 133 #define in6_rtchange in_rtchange 134 135 /* 136 * for KAME src sync over BSD*'s. XXX: FreeBSD (>=3) are VERY different from 137 * others... 138 */ 139 #define in6p_ip6_nxt inp_ipv6.ip6_nxt 140 #endif 141 142 /* 143 * ppratecheck() is available, so define it here. 144 */ 145 #define HAVE_PPSRATECHECK 146 147 extern struct domain inet6domain; 148 extern struct ip6protosw inet6sw[]; 149 extern u_char ip6_protox[]; 150 151 struct icmp6stat icmp6stat; 152 153 extern struct inpcbinfo ripcbinfo; 154 extern int icmp6errppslim; 155 static int icmp6errpps_count = 0; 156 static struct timeval icmp6errppslim_last; 157 extern int icmp6_nodeinfo; 158 159 static void icmp6_errcount (struct icmp6errstat *, int, int); 160 static int icmp6_rip6_input (struct mbuf **, int); 161 static int icmp6_ratelimit (const struct in6_addr *, const int, const int); 162 static const char *icmp6_redirect_diag (struct in6_addr *, 163 struct in6_addr *, struct in6_addr *); 164 #ifndef HAVE_PPSRATECHECK 165 static int ppsratecheck (struct timeval *, int *, int); 166 #endif 167 static struct mbuf *ni6_input (struct mbuf *, int); 168 static struct mbuf *ni6_nametodns (const char *, int, int); 169 static int ni6_dnsmatch (const char *, int, const char *, int); 170 static int ni6_addrs (struct icmp6_nodeinfo *, struct mbuf *, 171 struct ifnet **, char *); 172 static int ni6_store_addrs (struct icmp6_nodeinfo *, struct icmp6_nodeinfo *, 173 struct ifnet *, int); 174 static int icmp6_notify_error (struct mbuf *, int, int, int); 175 176 #ifdef COMPAT_RFC1885 177 static struct route_in6 icmp6_reflect_rt; 178 #endif 179 180 181 void 182 icmp6_init(void) 183 { 184 mld6_init(); 185 } 186 187 static void 188 icmp6_errcount(struct icmp6errstat *stat, int type, int code) 189 { 190 switch (type) { 191 case ICMP6_DST_UNREACH: 192 switch (code) { 193 case ICMP6_DST_UNREACH_NOROUTE: 194 stat->icp6errs_dst_unreach_noroute++; 195 return; 196 case ICMP6_DST_UNREACH_ADMIN: 197 stat->icp6errs_dst_unreach_admin++; 198 return; 199 case ICMP6_DST_UNREACH_BEYONDSCOPE: 200 stat->icp6errs_dst_unreach_beyondscope++; 201 return; 202 case ICMP6_DST_UNREACH_ADDR: 203 stat->icp6errs_dst_unreach_addr++; 204 return; 205 case ICMP6_DST_UNREACH_NOPORT: 206 stat->icp6errs_dst_unreach_noport++; 207 return; 208 } 209 break; 210 case ICMP6_PACKET_TOO_BIG: 211 stat->icp6errs_packet_too_big++; 212 return; 213 case ICMP6_TIME_EXCEEDED: 214 switch (code) { 215 case ICMP6_TIME_EXCEED_TRANSIT: 216 stat->icp6errs_time_exceed_transit++; 217 return; 218 case ICMP6_TIME_EXCEED_REASSEMBLY: 219 stat->icp6errs_time_exceed_reassembly++; 220 return; 221 } 222 break; 223 case ICMP6_PARAM_PROB: 224 switch (code) { 225 case ICMP6_PARAMPROB_HEADER: 226 stat->icp6errs_paramprob_header++; 227 return; 228 case ICMP6_PARAMPROB_NEXTHEADER: 229 stat->icp6errs_paramprob_nextheader++; 230 return; 231 case ICMP6_PARAMPROB_OPTION: 232 stat->icp6errs_paramprob_option++; 233 return; 234 } 235 break; 236 case ND_REDIRECT: 237 stat->icp6errs_redirect++; 238 return; 239 } 240 stat->icp6errs_unknown++; 241 } 242 243 /* 244 * Generate an error packet of type error in response to bad IP6 packet. 245 */ 246 void 247 icmp6_error(struct mbuf *m, int type, int code, int param) 248 { 249 struct ip6_hdr *oip6, *nip6; 250 struct icmp6_hdr *icmp6; 251 u_int preplen; 252 int off; 253 int nxt; 254 255 icmp6stat.icp6s_error++; 256 257 /* count per-type-code statistics */ 258 icmp6_errcount(&icmp6stat.icp6s_outerrhist, type, code); 259 260 #ifdef M_DECRYPTED /*not openbsd*/ 261 if (m->m_flags & M_DECRYPTED) { 262 icmp6stat.icp6s_canterror++; 263 goto freeit; 264 } 265 #endif 266 267 #ifndef PULLDOWN_TEST 268 IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), ); 269 #else 270 if (m->m_len < sizeof(struct ip6_hdr)) { 271 m = m_pullup(m, sizeof(struct ip6_hdr)); 272 if (m == NULL) 273 return; 274 } 275 #endif 276 oip6 = mtod(m, struct ip6_hdr *); 277 278 /* 279 * Multicast destination check. For unrecognized option errors, 280 * this check has already done in ip6_unknown_opt(), so we can 281 * check only for other errors. 282 */ 283 if ((m->m_flags & (M_BCAST|M_MCAST) || 284 IN6_IS_ADDR_MULTICAST(&oip6->ip6_dst)) && 285 (type != ICMP6_PACKET_TOO_BIG && 286 (type != ICMP6_PARAM_PROB || 287 code != ICMP6_PARAMPROB_OPTION))) 288 goto freeit; 289 290 /* Source address check. XXX: the case of anycast source? */ 291 if (IN6_IS_ADDR_UNSPECIFIED(&oip6->ip6_src) || 292 IN6_IS_ADDR_MULTICAST(&oip6->ip6_src)) 293 goto freeit; 294 295 /* 296 * If we are about to send ICMPv6 against ICMPv6 error/redirect, 297 * don't do it. 298 */ 299 nxt = -1; 300 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); 301 if (off >= 0 && nxt == IPPROTO_ICMPV6) { 302 struct icmp6_hdr *icp; 303 304 #ifndef PULLDOWN_TEST 305 IP6_EXTHDR_CHECK(m, 0, off + sizeof(struct icmp6_hdr), ); 306 icp = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 307 #else 308 IP6_EXTHDR_GET(icp, struct icmp6_hdr *, m, off, 309 sizeof(*icp)); 310 if (icp == NULL) { 311 icmp6stat.icp6s_tooshort++; 312 return; 313 } 314 #endif 315 if (icp->icmp6_type < ICMP6_ECHO_REQUEST || 316 icp->icmp6_type == ND_REDIRECT) { 317 /* 318 * ICMPv6 error 319 * Special case: for redirect (which is 320 * informational) we must not send icmp6 error. 321 */ 322 icmp6stat.icp6s_canterror++; 323 goto freeit; 324 } else { 325 /* ICMPv6 informational - send the error */ 326 } 327 } else { 328 /* non-ICMPv6 - send the error */ 329 } 330 331 oip6 = mtod(m, struct ip6_hdr *); /* adjust pointer */ 332 333 /* Finally, do rate limitation check. */ 334 if (icmp6_ratelimit(&oip6->ip6_src, type, code)) { 335 icmp6stat.icp6s_toofreq++; 336 goto freeit; 337 } 338 339 /* 340 * OK, ICMP6 can be generated. 341 */ 342 343 if (m->m_pkthdr.len >= ICMPV6_PLD_MAXLEN) 344 m_adj(m, ICMPV6_PLD_MAXLEN - m->m_pkthdr.len); 345 346 preplen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 347 M_PREPEND(m, preplen, MB_DONTWAIT); 348 if (m && m->m_len < preplen) 349 m = m_pullup(m, preplen); 350 if (m == NULL) { 351 nd6log((LOG_DEBUG, "ENOBUFS in icmp6_error %d\n", __LINE__)); 352 return; 353 } 354 355 nip6 = mtod(m, struct ip6_hdr *); 356 nip6->ip6_src = oip6->ip6_src; 357 nip6->ip6_dst = oip6->ip6_dst; 358 359 if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_src)) 360 oip6->ip6_src.s6_addr16[1] = 0; 361 if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_dst)) 362 oip6->ip6_dst.s6_addr16[1] = 0; 363 364 icmp6 = (struct icmp6_hdr *)(nip6 + 1); 365 icmp6->icmp6_type = type; 366 icmp6->icmp6_code = code; 367 icmp6->icmp6_pptr = htonl((u_int32_t)param); 368 369 /* 370 * icmp6_reflect() is designed to be in the input path. 371 * icmp6_error() can be called from both input and outut path, 372 * and if we are in output path rcvif could contain bogus value. 373 * clear m->m_pkthdr.rcvif for safety, we should have enough scope 374 * information in ip header (nip6). 375 */ 376 m->m_pkthdr.rcvif = NULL; 377 378 icmp6stat.icp6s_outhist[type]++; 379 icmp6_reflect(m, sizeof(struct ip6_hdr)); /* header order: IPv6 - ICMPv6 */ 380 381 return; 382 383 freeit: 384 /* 385 * If we can't tell wheter or not we can generate ICMP6, free it. 386 */ 387 m_freem(m); 388 } 389 390 /* 391 * Process a received ICMP6 message. 392 */ 393 int 394 icmp6_input(struct mbuf **mp, int *offp, int proto) 395 { 396 struct mbuf *m = *mp, *n; 397 struct ip6_hdr *ip6, *nip6; 398 struct icmp6_hdr *icmp6, *nicmp6; 399 int off = *offp; 400 int icmp6len = m->m_pkthdr.len - *offp; 401 int code, sum, noff; 402 403 #ifndef PULLDOWN_TEST 404 IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_hdr), IPPROTO_DONE); 405 /* m might change if M_LOOP. So, call mtod after this */ 406 #endif 407 408 /* 409 * Locate icmp6 structure in mbuf, and check 410 * that not corrupted and of at least minimum length 411 */ 412 413 ip6 = mtod(m, struct ip6_hdr *); 414 if (icmp6len < sizeof(struct icmp6_hdr)) { 415 icmp6stat.icp6s_tooshort++; 416 goto freeit; 417 } 418 419 /* 420 * calculate the checksum 421 */ 422 #ifndef PULLDOWN_TEST 423 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off); 424 #else 425 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 426 if (icmp6 == NULL) { 427 icmp6stat.icp6s_tooshort++; 428 return IPPROTO_DONE; 429 } 430 #endif 431 code = icmp6->icmp6_code; 432 433 if ((sum = in6_cksum(m, IPPROTO_ICMPV6, off, icmp6len)) != 0) { 434 nd6log((LOG_ERR, 435 "ICMP6 checksum error(%d|%x) %s\n", 436 icmp6->icmp6_type, sum, ip6_sprintf(&ip6->ip6_src))); 437 icmp6stat.icp6s_checksum++; 438 goto freeit; 439 } 440 441 if (faithprefix_p != NULL && (*faithprefix_p)(&ip6->ip6_dst)) { 442 /* 443 * Deliver very specific ICMP6 type only. 444 * This is important to deilver TOOBIG. Otherwise PMTUD 445 * will not work. 446 */ 447 switch (icmp6->icmp6_type) { 448 case ICMP6_DST_UNREACH: 449 case ICMP6_PACKET_TOO_BIG: 450 case ICMP6_TIME_EXCEEDED: 451 break; 452 default: 453 goto freeit; 454 } 455 } 456 457 icmp6stat.icp6s_inhist[icmp6->icmp6_type]++; 458 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_msg); 459 if (icmp6->icmp6_type < ICMP6_INFOMSG_MASK) 460 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_error); 461 462 switch (icmp6->icmp6_type) { 463 case ICMP6_DST_UNREACH: 464 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_dstunreach); 465 switch (code) { 466 case ICMP6_DST_UNREACH_NOROUTE: 467 code = PRC_UNREACH_NET; 468 break; 469 case ICMP6_DST_UNREACH_ADMIN: 470 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_adminprohib); 471 code = PRC_UNREACH_PROTOCOL; /* is this a good code? */ 472 break; 473 case ICMP6_DST_UNREACH_ADDR: 474 code = PRC_HOSTDEAD; 475 break; 476 #ifdef COMPAT_RFC1885 477 case ICMP6_DST_UNREACH_NOTNEIGHBOR: 478 code = PRC_UNREACH_SRCFAIL; 479 break; 480 #else 481 case ICMP6_DST_UNREACH_BEYONDSCOPE: 482 /* I mean "source address was incorrect." */ 483 code = PRC_PARAMPROB; 484 break; 485 #endif 486 case ICMP6_DST_UNREACH_NOPORT: 487 code = PRC_UNREACH_PORT; 488 break; 489 default: 490 goto badcode; 491 } 492 goto deliver; 493 break; 494 495 case ICMP6_PACKET_TOO_BIG: 496 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_pkttoobig); 497 if (code != 0) 498 goto badcode; 499 500 code = PRC_MSGSIZE; 501 502 /* 503 * Updating the path MTU will be done after examining 504 * intermediate extension headers. 505 */ 506 goto deliver; 507 break; 508 509 case ICMP6_TIME_EXCEEDED: 510 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_timeexceed); 511 switch (code) { 512 case ICMP6_TIME_EXCEED_TRANSIT: 513 case ICMP6_TIME_EXCEED_REASSEMBLY: 514 code += PRC_TIMXCEED_INTRANS; 515 break; 516 default: 517 goto badcode; 518 } 519 goto deliver; 520 break; 521 522 case ICMP6_PARAM_PROB: 523 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_paramprob); 524 switch (code) { 525 case ICMP6_PARAMPROB_NEXTHEADER: 526 code = PRC_UNREACH_PROTOCOL; 527 break; 528 case ICMP6_PARAMPROB_HEADER: 529 case ICMP6_PARAMPROB_OPTION: 530 code = PRC_PARAMPROB; 531 break; 532 default: 533 goto badcode; 534 } 535 goto deliver; 536 break; 537 538 case ICMP6_ECHO_REQUEST: 539 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echo); 540 if (code != 0) 541 goto badcode; 542 if ((n = m_copy(m, 0, M_COPYALL)) == NULL) { 543 /* Give up remote */ 544 break; 545 } 546 if ((n->m_flags & M_EXT) || 547 n->m_len < off + sizeof(struct icmp6_hdr)) { 548 struct mbuf *n0 = n; 549 const int maxlen = sizeof(*nip6) + sizeof(*nicmp6); 550 int n0len; 551 552 /* 553 * Prepare an internal mbuf. m_pullup() doesn't 554 * always copy the length we specified. 555 */ 556 if (maxlen >= MCLBYTES) { 557 /* Give up remote */ 558 m_freem(n0); 559 break; 560 } 561 n = m_getb(maxlen, MB_DONTWAIT, n0->m_type, M_PKTHDR); 562 if (n == NULL) { 563 /* Give up remote */ 564 m_freem(n0); 565 break; 566 } 567 n0len = n0->m_pkthdr.len; /* save for use below */ 568 M_MOVE_PKTHDR(n, n0); 569 /* 570 * Copy IPv6 and ICMPv6 only. 571 */ 572 nip6 = mtod(n, struct ip6_hdr *); 573 bcopy(ip6, nip6, sizeof(struct ip6_hdr)); 574 nicmp6 = (struct icmp6_hdr *)(nip6 + 1); 575 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr)); 576 noff = sizeof(struct ip6_hdr); 577 /* new mbuf contains only ipv6+icmpv6 headers */ 578 n->m_len = noff + sizeof(struct icmp6_hdr); 579 /* 580 * Adjust mbuf. ip6_plen will be adjusted in 581 * ip6_output(). 582 */ 583 m_adj(n0, off + sizeof(struct icmp6_hdr)); 584 /* recalculate complete packet size */ 585 n->m_pkthdr.len = n0len + (noff - off); 586 n->m_next = n0; 587 } else { 588 nip6 = mtod(n, struct ip6_hdr *); 589 nicmp6 = (struct icmp6_hdr *)((caddr_t)nip6 + off); 590 noff = off; 591 } 592 nicmp6->icmp6_type = ICMP6_ECHO_REPLY; 593 nicmp6->icmp6_code = 0; 594 if (n) { 595 icmp6stat.icp6s_reflect++; 596 icmp6stat.icp6s_outhist[ICMP6_ECHO_REPLY]++; 597 icmp6_reflect(n, noff); 598 } 599 break; 600 601 case ICMP6_ECHO_REPLY: 602 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echoreply); 603 if (code != 0) 604 goto badcode; 605 break; 606 607 case MLD_LISTENER_QUERY: 608 case MLD_LISTENER_REPORT: 609 if (icmp6len < sizeof(struct mld_hdr)) 610 goto badlen; 611 if (icmp6->icmp6_type == MLD_LISTENER_QUERY) /* XXX: ugly... */ 612 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldquery); 613 else 614 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldreport); 615 if ((n = m_copym(m, 0, M_COPYALL, MB_DONTWAIT)) == NULL) { 616 /* give up local */ 617 mld6_input(m, off); 618 m = NULL; 619 goto freeit; 620 } 621 mld6_input(n, off); 622 /* m stays. */ 623 break; 624 625 case MLD_LISTENER_DONE: 626 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mlddone); 627 if (icmp6len < sizeof(struct mld_hdr)) /* necessary? */ 628 goto badlen; 629 break; /* nothing to be done in kernel */ 630 631 case MLD_MTRACE_RESP: 632 case MLD_MTRACE: 633 /* XXX: these two are experimental. not officially defind. */ 634 /* XXX: per-interface statistics? */ 635 break; /* just pass it to applications */ 636 637 case ICMP6_WRUREQUEST: /* ICMP6_FQDN_QUERY */ 638 { 639 enum { WRU, FQDN } mode; 640 641 if (!icmp6_nodeinfo) 642 break; 643 644 if (icmp6len == sizeof(struct icmp6_hdr) + 4) 645 mode = WRU; 646 else if (icmp6len >= sizeof(struct icmp6_nodeinfo)) 647 mode = FQDN; 648 else 649 goto badlen; 650 651 #define hostnamelen strlen(hostname) 652 if (mode == FQDN) { 653 #ifndef PULLDOWN_TEST 654 IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_nodeinfo), 655 IPPROTO_DONE); 656 #endif 657 n = m_copy(m, 0, M_COPYALL); 658 if (n) 659 n = ni6_input(n, off); 660 /* XXX meaningless if n == NULL */ 661 noff = sizeof(struct ip6_hdr); 662 } else { 663 u_char *p; 664 int maxlen, maxhlen; 665 666 if ((icmp6_nodeinfo & 5) != 5) 667 break; 668 669 if (code != 0) 670 goto badcode; 671 maxlen = sizeof(*nip6) + sizeof(*nicmp6) + 4; 672 if (maxlen >= MCLBYTES) { 673 /* Give up remote */ 674 break; 675 } 676 n = m_getb(maxlen, MB_DONTWAIT, m->m_type, M_PKTHDR); 677 if (n == NULL) { 678 /* Give up remote */ 679 break; 680 } 681 if (!m_dup_pkthdr(n, m, MB_DONTWAIT)) { 682 /* 683 * Previous code did a blind M_COPY_PKTHDR 684 * and said "just for rcvif". If true, then 685 * we could tolerate the dup failing (due to 686 * the deep copy of the tag chain). For now 687 * be conservative and just fail. 688 */ 689 m_free(n); 690 break; 691 } 692 n->m_len = 0; 693 maxhlen = M_TRAILINGSPACE(n) - maxlen; 694 if (maxhlen > hostnamelen) 695 maxhlen = hostnamelen; 696 /* 697 * Copy IPv6 and ICMPv6 only. 698 */ 699 nip6 = mtod(n, struct ip6_hdr *); 700 bcopy(ip6, nip6, sizeof(struct ip6_hdr)); 701 nicmp6 = (struct icmp6_hdr *)(nip6 + 1); 702 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr)); 703 p = (u_char *)(nicmp6 + 1); 704 bzero(p, 4); 705 bcopy(hostname, p + 4, maxhlen); /* meaningless TTL */ 706 noff = sizeof(struct ip6_hdr); 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, MB_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, MB_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, MB_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, MB_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, MB_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(struct mbuf *m, int off, int icmp6len, int code) 856 { 857 struct icmp6_hdr *icmp6; 858 struct ip6_hdr *eip6; 859 u_int32_t notifymtu; 860 struct sockaddr_in6 icmp6src, icmp6dst; 861 862 if (icmp6len < sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr)) { 863 icmp6stat.icp6s_tooshort++; 864 goto freeit; 865 } 866 #ifndef PULLDOWN_TEST 867 IP6_EXTHDR_CHECK(m, off, 868 sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr), 869 -1); 870 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 871 #else 872 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, 873 sizeof(*icmp6) + sizeof(struct ip6_hdr)); 874 if (icmp6 == NULL) { 875 icmp6stat.icp6s_tooshort++; 876 return (-1); 877 } 878 #endif 879 eip6 = (struct ip6_hdr *)(icmp6 + 1); 880 881 /* Detect the upper level protocol */ 882 { 883 void (*ctlfunc) (int, struct sockaddr *, void *); 884 u_int8_t nxt = eip6->ip6_nxt; 885 int eoff = off + sizeof(struct icmp6_hdr) + 886 sizeof(struct ip6_hdr); 887 struct ip6ctlparam ip6cp; 888 struct in6_addr *finaldst = NULL; 889 int icmp6type = icmp6->icmp6_type; 890 struct ip6_frag *fh; 891 struct ip6_rthdr *rth; 892 struct ip6_rthdr0 *rth0; 893 int rthlen; 894 895 while (1) { /* XXX: should avoid infinite loop explicitly? */ 896 struct ip6_ext *eh; 897 898 switch (nxt) { 899 case IPPROTO_HOPOPTS: 900 case IPPROTO_DSTOPTS: 901 case IPPROTO_AH: 902 #ifndef PULLDOWN_TEST 903 IP6_EXTHDR_CHECK(m, 0, eoff + 904 sizeof(struct ip6_ext), 905 -1); 906 eh = (struct ip6_ext *)(mtod(m, caddr_t) 907 + eoff); 908 #else 909 IP6_EXTHDR_GET(eh, struct ip6_ext *, m, 910 eoff, sizeof(*eh)); 911 if (eh == NULL) { 912 icmp6stat.icp6s_tooshort++; 913 return (-1); 914 } 915 #endif 916 917 if (nxt == IPPROTO_AH) 918 eoff += (eh->ip6e_len + 2) << 2; 919 else 920 eoff += (eh->ip6e_len + 1) << 3; 921 nxt = eh->ip6e_nxt; 922 break; 923 case IPPROTO_ROUTING: 924 /* 925 * When the erroneous packet contains a 926 * routing header, we should examine the 927 * header to determine the final destination. 928 * Otherwise, we can't properly update 929 * information that depends on the final 930 * destination (e.g. path MTU). 931 */ 932 #ifndef PULLDOWN_TEST 933 IP6_EXTHDR_CHECK(m, 0, eoff + sizeof(*rth), 934 -1); 935 rth = (struct ip6_rthdr *)(mtod(m, caddr_t) 936 + eoff); 937 #else 938 IP6_EXTHDR_GET(rth, struct ip6_rthdr *, m, 939 eoff, sizeof(*rth)); 940 if (rth == NULL) { 941 icmp6stat.icp6s_tooshort++; 942 return (-1); 943 } 944 #endif 945 rthlen = (rth->ip6r_len + 1) << 3; 946 /* 947 * XXX: currently there is no 948 * officially defined type other 949 * than type-0. 950 * Note that if the segment left field 951 * is 0, all intermediate hops must 952 * have been passed. 953 */ 954 if (rth->ip6r_segleft && 955 rth->ip6r_type == IPV6_RTHDR_TYPE_0) { 956 int hops; 957 958 #ifndef PULLDOWN_TEST 959 IP6_EXTHDR_CHECK(m, 0, eoff + rthlen, 960 -1); 961 rth0 = (struct ip6_rthdr0 *)(mtod(m, caddr_t) + eoff); 962 #else 963 IP6_EXTHDR_GET(rth0, 964 struct ip6_rthdr0 *, m, 965 eoff, rthlen); 966 if (rth0 == NULL) { 967 icmp6stat.icp6s_tooshort++; 968 return (-1); 969 } 970 #endif 971 /* just ignore a bogus header */ 972 if ((rth0->ip6r0_len % 2) == 0 && 973 (hops = rth0->ip6r0_len/2)) 974 finaldst = (struct in6_addr *)(rth0 + 1) + (hops - 1); 975 } 976 eoff += rthlen; 977 nxt = rth->ip6r_nxt; 978 break; 979 case IPPROTO_FRAGMENT: 980 #ifndef PULLDOWN_TEST 981 IP6_EXTHDR_CHECK(m, 0, eoff + 982 sizeof(struct ip6_frag), 983 -1); 984 fh = (struct ip6_frag *)(mtod(m, caddr_t) 985 + eoff); 986 #else 987 IP6_EXTHDR_GET(fh, struct ip6_frag *, m, 988 eoff, sizeof(*fh)); 989 if (fh == NULL) { 990 icmp6stat.icp6s_tooshort++; 991 return (-1); 992 } 993 #endif 994 /* 995 * Data after a fragment header is meaningless 996 * unless it is the first fragment, but 997 * we'll go to the notify label for path MTU 998 * discovery. 999 */ 1000 if (fh->ip6f_offlg & IP6F_OFF_MASK) 1001 goto notify; 1002 1003 eoff += sizeof(struct ip6_frag); 1004 nxt = fh->ip6f_nxt; 1005 break; 1006 default: 1007 /* 1008 * This case includes ESP and the No Next 1009 * Header. In such cases going to the notify 1010 * label does not have any meaning 1011 * (i.e. ctlfunc will be NULL), but we go 1012 * anyway since we might have to update 1013 * path MTU information. 1014 */ 1015 goto notify; 1016 } 1017 } 1018 notify: 1019 #ifndef PULLDOWN_TEST 1020 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 1021 #else 1022 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, 1023 sizeof(*icmp6) + sizeof(struct ip6_hdr)); 1024 if (icmp6 == NULL) { 1025 icmp6stat.icp6s_tooshort++; 1026 return (-1); 1027 } 1028 #endif 1029 1030 eip6 = (struct ip6_hdr *)(icmp6 + 1); 1031 bzero(&icmp6dst, sizeof(icmp6dst)); 1032 icmp6dst.sin6_len = sizeof(struct sockaddr_in6); 1033 icmp6dst.sin6_family = AF_INET6; 1034 if (finaldst == NULL) 1035 icmp6dst.sin6_addr = eip6->ip6_dst; 1036 else 1037 icmp6dst.sin6_addr = *finaldst; 1038 icmp6dst.sin6_scope_id = in6_addr2scopeid(m->m_pkthdr.rcvif, 1039 &icmp6dst.sin6_addr); 1040 if (in6_embedscope(&icmp6dst.sin6_addr, &icmp6dst, 1041 NULL, NULL)) { 1042 /* should be impossbile */ 1043 nd6log((LOG_DEBUG, 1044 "icmp6_notify_error: in6_embedscope failed\n")); 1045 goto freeit; 1046 } 1047 1048 /* 1049 * retrieve parameters from the inner IPv6 header, and convert 1050 * them into sockaddr structures. 1051 */ 1052 bzero(&icmp6src, sizeof(icmp6src)); 1053 icmp6src.sin6_len = sizeof(struct sockaddr_in6); 1054 icmp6src.sin6_family = AF_INET6; 1055 icmp6src.sin6_addr = eip6->ip6_src; 1056 icmp6src.sin6_scope_id = in6_addr2scopeid(m->m_pkthdr.rcvif, 1057 &icmp6src.sin6_addr); 1058 if (in6_embedscope(&icmp6src.sin6_addr, &icmp6src, 1059 NULL, NULL)) { 1060 /* should be impossbile */ 1061 nd6log((LOG_DEBUG, 1062 "icmp6_notify_error: in6_embedscope failed\n")); 1063 goto freeit; 1064 } 1065 icmp6src.sin6_flowinfo = 1066 (eip6->ip6_flow & IPV6_FLOWLABEL_MASK); 1067 1068 if (finaldst == NULL) 1069 finaldst = &eip6->ip6_dst; 1070 ip6cp.ip6c_m = m; 1071 ip6cp.ip6c_icmp6 = icmp6; 1072 ip6cp.ip6c_ip6 = (struct ip6_hdr *)(icmp6 + 1); 1073 ip6cp.ip6c_off = eoff; 1074 ip6cp.ip6c_finaldst = finaldst; 1075 ip6cp.ip6c_src = &icmp6src; 1076 ip6cp.ip6c_nxt = nxt; 1077 1078 if (icmp6type == ICMP6_PACKET_TOO_BIG) { 1079 notifymtu = ntohl(icmp6->icmp6_mtu); 1080 ip6cp.ip6c_cmdarg = (void *)¬ifymtu; 1081 icmp6_mtudisc_update(&ip6cp, 1); /*XXX*/ 1082 } 1083 1084 ctlfunc = (void (*) (int, struct sockaddr *, void *)) 1085 (inet6sw[ip6_protox[nxt]].pr_ctlinput); 1086 if (ctlfunc) { 1087 (*ctlfunc)(code, (struct sockaddr *)&icmp6dst, &ip6cp); 1088 } 1089 } 1090 return (0); 1091 1092 freeit: 1093 m_freem(m); 1094 return (-1); 1095 } 1096 1097 void 1098 icmp6_mtudisc_update(struct ip6ctlparam *ip6cp, int validated) 1099 { 1100 struct in6_addr *dst = ip6cp->ip6c_finaldst; 1101 struct icmp6_hdr *icmp6 = ip6cp->ip6c_icmp6; 1102 struct mbuf *m = ip6cp->ip6c_m; /* will be necessary for scope issue */ 1103 u_int mtu = ntohl(icmp6->icmp6_mtu); 1104 struct rtentry *rt = NULL; 1105 struct sockaddr_in6 sin6; 1106 1107 if (!validated) 1108 return; 1109 1110 bzero(&sin6, sizeof(sin6)); 1111 sin6.sin6_family = PF_INET6; 1112 sin6.sin6_len = sizeof(struct sockaddr_in6); 1113 sin6.sin6_addr = *dst; 1114 /* XXX normally, this won't happen */ 1115 if (IN6_IS_ADDR_LINKLOCAL(dst)) { 1116 sin6.sin6_addr.s6_addr16[1] = 1117 htons(m->m_pkthdr.rcvif->if_index); 1118 } 1119 /* sin6.sin6_scope_id = XXX: should be set if DST is a scoped addr */ 1120 rt = rtpurelookup((struct sockaddr *)&sin6); 1121 if (rt != NULL && (rt->rt_flags & RTF_HOST) && 1122 !(rt->rt_rmx.rmx_locks & RTV_MTU)) { 1123 if (mtu < IPV6_MMTU) { /* XXX */ 1124 rt->rt_rmx.rmx_locks |= RTV_MTU; 1125 } else if (mtu < rt->rt_ifp->if_mtu && 1126 rt->rt_rmx.rmx_mtu > mtu) { 1127 icmp6stat.icp6s_pmtuchg++; 1128 rt->rt_rmx.rmx_mtu = mtu; 1129 } 1130 } 1131 if (rt) 1132 --rt->rt_refcnt; 1133 } 1134 1135 /* 1136 * Process a Node Information Query packet, based on 1137 * draft-ietf-ipngwg-icmp-name-lookups-07. 1138 * 1139 * Spec incompatibilities: 1140 * - IPv6 Subject address handling 1141 * - IPv4 Subject address handling support missing 1142 * - Proxy reply (answer even if it's not for me) 1143 * - joins NI group address at in6_ifattach() time only, does not cope 1144 * with hostname changes by sethostname(3) 1145 */ 1146 #define hostnamelen strlen(hostname) 1147 static struct mbuf * 1148 ni6_input(struct mbuf *m, int off) 1149 { 1150 struct icmp6_nodeinfo *ni6, *nni6; 1151 struct mbuf *n = NULL; 1152 u_int16_t qtype; 1153 int subjlen; 1154 int replylen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo); 1155 struct ni_reply_fqdn *fqdn; 1156 int addrs; /* for NI_QTYPE_NODEADDR */ 1157 struct ifnet *ifp = NULL; /* for NI_QTYPE_NODEADDR */ 1158 struct sockaddr_in6 sin6; /* double meaning; ip6_dst and subjectaddr */ 1159 struct sockaddr_in6 sin6_d; /* XXX: we should retrieve this from m_aux */ 1160 struct ip6_hdr *ip6; 1161 int oldfqdn = 0; /* if 1, return pascal string (03 draft) */ 1162 char *subj = NULL; 1163 struct in6_ifaddr *ia6 = NULL; 1164 1165 ip6 = mtod(m, struct ip6_hdr *); 1166 #ifndef PULLDOWN_TEST 1167 ni6 = (struct icmp6_nodeinfo *)(mtod(m, caddr_t) + off); 1168 #else 1169 IP6_EXTHDR_GET(ni6, struct icmp6_nodeinfo *, m, off, sizeof(*ni6)); 1170 if (ni6 == NULL) { 1171 /* m is already reclaimed */ 1172 return NULL; 1173 } 1174 #endif 1175 1176 /* 1177 * Validate IPv6 destination address. 1178 * 1179 * The Responder must discard the Query without further processing 1180 * unless it is one of the Responder's unicast or anycast addresses, or 1181 * a link-local scope multicast address which the Responder has joined. 1182 * [icmp-name-lookups-07, Section 4.] 1183 */ 1184 bzero(&sin6, sizeof(sin6)); 1185 sin6.sin6_family = AF_INET6; 1186 sin6.sin6_len = sizeof(struct sockaddr_in6); 1187 bcopy(&ip6->ip6_dst, &sin6.sin6_addr, sizeof(sin6.sin6_addr)); 1188 /* XXX scopeid */ 1189 if ((ia6 = (struct in6_ifaddr *)ifa_ifwithaddr((struct sockaddr *)&sin6)) != NULL) { 1190 /* unicast/anycast, fine */ 1191 if ((ia6->ia6_flags & IN6_IFF_TEMPORARY) && 1192 (icmp6_nodeinfo & 4) == 0) { 1193 nd6log((LOG_DEBUG, "ni6_input: ignore node info to " 1194 "a temporary address in %s:%d", 1195 __FILE__, __LINE__)); 1196 goto bad; 1197 } 1198 } else if (IN6_IS_ADDR_MC_LINKLOCAL(&sin6.sin6_addr)) 1199 ; /* link-local multicast, fine */ 1200 else 1201 goto bad; 1202 1203 /* validate query Subject field. */ 1204 qtype = ntohs(ni6->ni_qtype); 1205 subjlen = m->m_pkthdr.len - off - sizeof(struct icmp6_nodeinfo); 1206 switch (qtype) { 1207 case NI_QTYPE_NOOP: 1208 case NI_QTYPE_SUPTYPES: 1209 /* 07 draft */ 1210 if (ni6->ni_code == ICMP6_NI_SUBJ_FQDN && subjlen == 0) 1211 break; 1212 /* FALLTHROUGH */ 1213 case NI_QTYPE_FQDN: 1214 case NI_QTYPE_NODEADDR: 1215 switch (ni6->ni_code) { 1216 case ICMP6_NI_SUBJ_IPV6: 1217 #if ICMP6_NI_SUBJ_IPV6 != 0 1218 case 0: 1219 #endif 1220 /* 1221 * backward compatibility - try to accept 03 draft 1222 * format, where no Subject is present. 1223 */ 1224 if (qtype == NI_QTYPE_FQDN && ni6->ni_code == 0 && 1225 subjlen == 0) { 1226 oldfqdn++; 1227 break; 1228 } 1229 #if ICMP6_NI_SUBJ_IPV6 != 0 1230 if (ni6->ni_code != ICMP6_NI_SUBJ_IPV6) 1231 goto bad; 1232 #endif 1233 1234 if (subjlen != sizeof(sin6.sin6_addr)) 1235 goto bad; 1236 1237 /* 1238 * Validate Subject address. 1239 * 1240 * Not sure what exactly "address belongs to the node" 1241 * means in the spec, is it just unicast, or what? 1242 * 1243 * At this moment we consider Subject address as 1244 * "belong to the node" if the Subject address equals 1245 * to the IPv6 destination address; validation for 1246 * IPv6 destination address should have done enough 1247 * check for us. 1248 * 1249 * We do not do proxy at this moment. 1250 */ 1251 /* m_pulldown instead of copy? */ 1252 m_copydata(m, off + sizeof(struct icmp6_nodeinfo), 1253 subjlen, (caddr_t)&sin6.sin6_addr); 1254 sin6.sin6_scope_id = in6_addr2scopeid(m->m_pkthdr.rcvif, 1255 &sin6.sin6_addr); 1256 in6_embedscope(&sin6.sin6_addr, &sin6, NULL, NULL); 1257 bzero(&sin6_d, sizeof(sin6_d)); 1258 sin6_d.sin6_family = AF_INET6; /* not used, actually */ 1259 sin6_d.sin6_len = sizeof(sin6_d); /* ditto */ 1260 sin6_d.sin6_addr = ip6->ip6_dst; 1261 sin6_d.sin6_scope_id = in6_addr2scopeid(m->m_pkthdr.rcvif, 1262 &ip6->ip6_dst); 1263 in6_embedscope(&sin6_d.sin6_addr, &sin6_d, NULL, NULL); 1264 subj = (char *)&sin6; 1265 if (SA6_ARE_ADDR_EQUAL(&sin6, &sin6_d)) 1266 break; 1267 1268 /* 1269 * XXX if we are to allow other cases, we should really 1270 * be careful about scope here. 1271 * basically, we should disallow queries toward IPv6 1272 * destination X with subject Y, if scope(X) > scope(Y). 1273 * if we allow scope(X) > scope(Y), it will result in 1274 * information leakage across scope boundary. 1275 */ 1276 goto bad; 1277 1278 case ICMP6_NI_SUBJ_FQDN: 1279 /* 1280 * Validate Subject name with gethostname(3). 1281 * 1282 * The behavior may need some debate, since: 1283 * - we are not sure if the node has FQDN as 1284 * hostname (returned by gethostname(3)). 1285 * - the code does wildcard match for truncated names. 1286 * however, we are not sure if we want to perform 1287 * wildcard match, if gethostname(3) side has 1288 * truncated hostname. 1289 */ 1290 n = ni6_nametodns(hostname, hostnamelen, 0); 1291 if (!n || n->m_next || n->m_len == 0) 1292 goto bad; 1293 IP6_EXTHDR_GET(subj, char *, m, 1294 off + sizeof(struct icmp6_nodeinfo), subjlen); 1295 if (subj == NULL) 1296 goto bad; 1297 if (!ni6_dnsmatch(subj, subjlen, mtod(n, const char *), 1298 n->m_len)) { 1299 goto bad; 1300 } 1301 m_freem(n); 1302 n = NULL; 1303 break; 1304 1305 case ICMP6_NI_SUBJ_IPV4: /* XXX: to be implemented? */ 1306 default: 1307 goto bad; 1308 } 1309 break; 1310 } 1311 1312 /* refuse based on configuration. XXX ICMP6_NI_REFUSED? */ 1313 switch (qtype) { 1314 case NI_QTYPE_FQDN: 1315 if ((icmp6_nodeinfo & 1) == 0) 1316 goto bad; 1317 break; 1318 case NI_QTYPE_NODEADDR: 1319 if ((icmp6_nodeinfo & 2) == 0) 1320 goto bad; 1321 break; 1322 } 1323 1324 /* guess reply length */ 1325 switch (qtype) { 1326 case NI_QTYPE_NOOP: 1327 break; /* no reply data */ 1328 case NI_QTYPE_SUPTYPES: 1329 replylen += sizeof(u_int32_t); 1330 break; 1331 case NI_QTYPE_FQDN: 1332 /* XXX will append an mbuf */ 1333 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1334 break; 1335 case NI_QTYPE_NODEADDR: 1336 addrs = ni6_addrs(ni6, m, &ifp, subj); 1337 if ((replylen += addrs * (sizeof(struct in6_addr) + 1338 sizeof(u_int32_t))) > MCLBYTES) 1339 replylen = MCLBYTES; /* XXX: will truncate pkt later */ 1340 break; 1341 default: 1342 /* 1343 * XXX: We must return a reply with the ICMP6 code 1344 * `unknown Qtype' in this case. However we regard the case 1345 * as an FQDN query for backward compatibility. 1346 * Older versions set a random value to this field, 1347 * so it rarely varies in the defined qtypes. 1348 * But the mechanism is not reliable... 1349 * maybe we should obsolete older versions. 1350 */ 1351 qtype = NI_QTYPE_FQDN; 1352 /* XXX will append an mbuf */ 1353 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1354 oldfqdn++; 1355 break; 1356 } 1357 1358 /* allocate an mbuf to reply. */ 1359 if (replylen > MCLBYTES) { 1360 /* 1361 * XXX: should we try to allocate more? But MCLBYTES 1362 * is probably much larger than IPV6_MMTU... 1363 */ 1364 goto bad; 1365 } 1366 n = m_getb(replylen, MB_DONTWAIT, m->m_type, M_PKTHDR); 1367 if (n == NULL) { 1368 m_freem(m); 1369 return (NULL); 1370 } 1371 M_MOVE_PKTHDR(n, m); /* just for recvif */ 1372 n->m_pkthdr.len = n->m_len = replylen; 1373 1374 /* copy mbuf header and IPv6 + Node Information base headers */ 1375 bcopy(mtod(m, caddr_t), mtod(n, caddr_t), sizeof(struct ip6_hdr)); 1376 nni6 = (struct icmp6_nodeinfo *)(mtod(n, struct ip6_hdr *) + 1); 1377 bcopy((caddr_t)ni6, (caddr_t)nni6, sizeof(struct icmp6_nodeinfo)); 1378 1379 /* qtype dependent procedure */ 1380 switch (qtype) { 1381 case NI_QTYPE_NOOP: 1382 nni6->ni_code = ICMP6_NI_SUCCESS; 1383 nni6->ni_flags = 0; 1384 break; 1385 case NI_QTYPE_SUPTYPES: 1386 { 1387 u_int32_t v; 1388 nni6->ni_code = ICMP6_NI_SUCCESS; 1389 nni6->ni_flags = htons(0x0000); /* raw bitmap */ 1390 /* supports NOOP, SUPTYPES, FQDN, and NODEADDR */ 1391 v = (u_int32_t)htonl(0x0000000f); 1392 bcopy(&v, nni6 + 1, sizeof(u_int32_t)); 1393 break; 1394 } 1395 case NI_QTYPE_FQDN: 1396 nni6->ni_code = ICMP6_NI_SUCCESS; 1397 fqdn = (struct ni_reply_fqdn *)(mtod(n, caddr_t) + 1398 sizeof(struct ip6_hdr) + 1399 sizeof(struct icmp6_nodeinfo)); 1400 nni6->ni_flags = 0; /* XXX: meaningless TTL */ 1401 fqdn->ni_fqdn_ttl = 0; /* ditto. */ 1402 /* 1403 * XXX do we really have FQDN in variable "hostname"? 1404 */ 1405 n->m_next = ni6_nametodns(hostname, hostnamelen, oldfqdn); 1406 if (n->m_next == NULL) 1407 goto bad; 1408 /* XXX we assume that n->m_next is not a chain */ 1409 if (n->m_next->m_next != NULL) 1410 goto bad; 1411 n->m_pkthdr.len += n->m_next->m_len; 1412 break; 1413 case NI_QTYPE_NODEADDR: 1414 { 1415 int lenlim, copied; 1416 1417 nni6->ni_code = ICMP6_NI_SUCCESS; 1418 n->m_pkthdr.len = n->m_len = 1419 sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo); 1420 lenlim = M_TRAILINGSPACE(n); 1421 copied = ni6_store_addrs(ni6, nni6, ifp, lenlim); 1422 /* XXX: reset mbuf length */ 1423 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) + 1424 sizeof(struct icmp6_nodeinfo) + copied; 1425 break; 1426 } 1427 default: 1428 break; /* XXX impossible! */ 1429 } 1430 1431 nni6->ni_type = ICMP6_NI_REPLY; 1432 m_freem(m); 1433 return (n); 1434 1435 bad: 1436 m_freem(m); 1437 if (n) 1438 m_freem(n); 1439 return (NULL); 1440 } 1441 #undef hostnamelen 1442 1443 /* 1444 * make a mbuf with DNS-encoded string. no compression support. 1445 * 1446 * XXX names with less than 2 dots (like "foo" or "foo.section") will be 1447 * treated as truncated name (two \0 at the end). this is a wild guess. 1448 */ 1449 static struct mbuf * 1450 ni6_nametodns(const char *name, int namelen, 1451 int old) /* return pascal string if non-zero */ 1452 { 1453 struct mbuf *m; 1454 char *cp, *ep; 1455 const char *p, *q; 1456 int i, len, nterm; 1457 1458 if (old) 1459 len = namelen + 1; 1460 else 1461 len = MCLBYTES; 1462 1463 /* because MAXHOSTNAMELEN is usually 256, we use cluster mbuf */ 1464 m = m_getb(len, MB_DONTWAIT, MT_DATA, 0); 1465 if (!m) 1466 goto fail; 1467 1468 if (old) { 1469 m->m_len = len; 1470 *mtod(m, char *) = namelen; 1471 bcopy(name, mtod(m, char *) + 1, namelen); 1472 return m; 1473 } else { 1474 m->m_len = 0; 1475 cp = mtod(m, char *); 1476 ep = mtod(m, char *) + M_TRAILINGSPACE(m); 1477 1478 /* if not certain about my name, return empty buffer */ 1479 if (namelen == 0) 1480 return m; 1481 1482 /* 1483 * guess if it looks like shortened hostname, or FQDN. 1484 * shortened hostname needs two trailing "\0". 1485 */ 1486 i = 0; 1487 for (p = name; p < name + namelen; p++) { 1488 if (*p && *p == '.') 1489 i++; 1490 } 1491 if (i < 2) 1492 nterm = 2; 1493 else 1494 nterm = 1; 1495 1496 p = name; 1497 while (cp < ep && p < name + namelen) { 1498 i = 0; 1499 for (q = p; q < name + namelen && *q && *q != '.'; q++) 1500 i++; 1501 /* result does not fit into mbuf */ 1502 if (cp + i + 1 >= ep) 1503 goto fail; 1504 /* 1505 * DNS label length restriction, RFC1035 page 8. 1506 * "i == 0" case is included here to avoid returning 1507 * 0-length label on "foo..bar". 1508 */ 1509 if (i <= 0 || i >= 64) 1510 goto fail; 1511 *cp++ = i; 1512 bcopy(p, cp, i); 1513 cp += i; 1514 p = q; 1515 if (p < name + namelen && *p == '.') 1516 p++; 1517 } 1518 /* termination */ 1519 if (cp + nterm >= ep) 1520 goto fail; 1521 while (nterm-- > 0) 1522 *cp++ = '\0'; 1523 m->m_len = cp - mtod(m, char *); 1524 return m; 1525 } 1526 1527 panic("should not reach here"); 1528 /* NOTREACHED */ 1529 1530 fail: 1531 if (m) 1532 m_freem(m); 1533 return NULL; 1534 } 1535 1536 /* 1537 * check if two DNS-encoded string matches. takes care of truncated 1538 * form (with \0\0 at the end). no compression support. 1539 * XXX upper/lowercase match (see RFC2065) 1540 */ 1541 static int 1542 ni6_dnsmatch(const char *a, int alen, const char *b, int blen) 1543 { 1544 const char *a0, *b0; 1545 int l; 1546 1547 /* simplest case - need validation? */ 1548 if (alen == blen && bcmp(a, b, alen) == 0) 1549 return 1; 1550 1551 a0 = a; 1552 b0 = b; 1553 1554 /* termination is mandatory */ 1555 if (alen < 2 || blen < 2) 1556 return 0; 1557 if (a0[alen - 1] != '\0' || b0[blen - 1] != '\0') 1558 return 0; 1559 alen--; 1560 blen--; 1561 1562 while (a - a0 < alen && b - b0 < blen) { 1563 if (a - a0 + 1 > alen || b - b0 + 1 > blen) 1564 return 0; 1565 1566 if ((signed char)a[0] < 0 || (signed char)b[0] < 0) 1567 return 0; 1568 /* we don't support compression yet */ 1569 if (a[0] >= 64 || b[0] >= 64) 1570 return 0; 1571 1572 /* truncated case */ 1573 if (a[0] == 0 && a - a0 == alen - 1) 1574 return 1; 1575 if (b[0] == 0 && b - b0 == blen - 1) 1576 return 1; 1577 if (a[0] == 0 || b[0] == 0) 1578 return 0; 1579 1580 if (a[0] != b[0]) 1581 return 0; 1582 l = a[0]; 1583 if (a - a0 + 1 + l > alen || b - b0 + 1 + l > blen) 1584 return 0; 1585 if (bcmp(a + 1, b + 1, l) != 0) 1586 return 0; 1587 1588 a += 1 + l; 1589 b += 1 + l; 1590 } 1591 1592 if (a - a0 == alen && b - b0 == blen) 1593 return 1; 1594 else 1595 return 0; 1596 } 1597 1598 /* 1599 * calculate the number of addresses to be returned in the node info reply. 1600 */ 1601 static int 1602 ni6_addrs(struct icmp6_nodeinfo *ni6, struct mbuf *m, struct ifnet **ifpp, 1603 char *subj) 1604 { 1605 struct ifnet *ifp; 1606 struct in6_ifaddr *ifa6; 1607 struct sockaddr_in6 *subj_ip6 = NULL; /* XXX pedant */ 1608 int addrs = 0, addrsofif, iffound = 0; 1609 int niflags = ni6->ni_flags; 1610 1611 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0) { 1612 switch (ni6->ni_code) { 1613 case ICMP6_NI_SUBJ_IPV6: 1614 if (subj == NULL) /* must be impossible... */ 1615 return (0); 1616 subj_ip6 = (struct sockaddr_in6 *)subj; 1617 break; 1618 default: 1619 /* 1620 * XXX: we only support IPv6 subject address for 1621 * this Qtype. 1622 */ 1623 return (0); 1624 } 1625 } 1626 1627 for (ifp = TAILQ_FIRST(&ifnet); ifp; ifp = TAILQ_NEXT(ifp, if_list)) 1628 { 1629 struct ifaddr_container *ifac; 1630 1631 addrsofif = 0; 1632 TAILQ_FOREACH(ifac, &ifp->if_addrheads[mycpuid], ifa_link) 1633 { 1634 struct ifaddr *ifa = ifac->ifa; 1635 1636 if (ifa->ifa_addr->sa_family != AF_INET6) 1637 continue; 1638 ifa6 = (struct in6_ifaddr *)ifa; 1639 1640 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0 && 1641 IN6_ARE_ADDR_EQUAL(&subj_ip6->sin6_addr, 1642 &ifa6->ia_addr.sin6_addr)) 1643 iffound = 1; 1644 1645 /* 1646 * IPv4-mapped addresses can only be returned by a 1647 * Node Information proxy, since they represent 1648 * addresses of IPv4-only nodes, which perforce do 1649 * not implement this protocol. 1650 * [icmp-name-lookups-07, Section 5.4] 1651 * So we don't support NI_NODEADDR_FLAG_COMPAT in 1652 * this function at this moment. 1653 */ 1654 1655 /* What do we have to do about ::1? */ 1656 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1657 case IPV6_ADDR_SCOPE_LINKLOCAL: 1658 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0) 1659 continue; 1660 break; 1661 case IPV6_ADDR_SCOPE_SITELOCAL: 1662 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0) 1663 continue; 1664 break; 1665 case IPV6_ADDR_SCOPE_GLOBAL: 1666 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0) 1667 continue; 1668 break; 1669 default: 1670 continue; 1671 } 1672 1673 /* 1674 * check if anycast is okay. 1675 * XXX: just experimental. not in the spec. 1676 */ 1677 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) && 1678 !(niflags & NI_NODEADDR_FLAG_ANYCAST)) 1679 continue; /* we need only unicast addresses */ 1680 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) && 1681 (icmp6_nodeinfo & 4) == 0) { 1682 continue; 1683 } 1684 addrsofif++; /* count the address */ 1685 } 1686 if (iffound) { 1687 *ifpp = ifp; 1688 return (addrsofif); 1689 } 1690 1691 addrs += addrsofif; 1692 } 1693 1694 return (addrs); 1695 } 1696 1697 static int 1698 ni6_store_addrs(struct icmp6_nodeinfo *ni6, struct icmp6_nodeinfo *nni6, 1699 struct ifnet *ifp0, int resid) 1700 { 1701 struct ifnet *ifp = ifp0 ? ifp0 : TAILQ_FIRST(&ifnet); 1702 struct in6_ifaddr *ifa6; 1703 struct ifnet *ifp_dep = NULL; 1704 int copied = 0, allow_deprecated = 0; 1705 u_char *cp = (u_char *)(nni6 + 1); 1706 int niflags = ni6->ni_flags; 1707 u_int32_t ltime; 1708 1709 if (ifp0 == NULL && !(niflags & NI_NODEADDR_FLAG_ALL)) 1710 return (0); /* needless to copy */ 1711 1712 again: 1713 1714 for (; ifp; ifp = TAILQ_NEXT(ifp, if_list)) 1715 { 1716 struct ifaddr_container *ifac; 1717 1718 TAILQ_FOREACH(ifac, &ifp->if_addrheads[mycpuid], ifa_link) { 1719 struct ifaddr *ifa = ifac->ifa; 1720 1721 if (ifa->ifa_addr->sa_family != AF_INET6) 1722 continue; 1723 ifa6 = (struct in6_ifaddr *)ifa; 1724 1725 if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) && 1726 allow_deprecated == 0) { 1727 /* 1728 * prefererred address should be put before 1729 * deprecated addresses. 1730 */ 1731 1732 /* record the interface for later search */ 1733 if (ifp_dep == NULL) 1734 ifp_dep = ifp; 1735 1736 continue; 1737 } 1738 else if (!(ifa6->ia6_flags & IN6_IFF_DEPRECATED) && 1739 allow_deprecated != 0) 1740 continue; /* we now collect deprecated addrs */ 1741 1742 /* What do we have to do about ::1? */ 1743 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1744 case IPV6_ADDR_SCOPE_LINKLOCAL: 1745 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0) 1746 continue; 1747 break; 1748 case IPV6_ADDR_SCOPE_SITELOCAL: 1749 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0) 1750 continue; 1751 break; 1752 case IPV6_ADDR_SCOPE_GLOBAL: 1753 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0) 1754 continue; 1755 break; 1756 default: 1757 continue; 1758 } 1759 1760 /* 1761 * check if anycast is okay. 1762 * XXX: just experimental. not in the spec. 1763 */ 1764 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) && 1765 !(niflags & NI_NODEADDR_FLAG_ANYCAST)) 1766 continue; 1767 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) && 1768 (icmp6_nodeinfo & 4) == 0) { 1769 continue; 1770 } 1771 1772 /* now we can copy the address */ 1773 if (resid < sizeof(struct in6_addr) + 1774 sizeof(u_int32_t)) { 1775 /* 1776 * We give up much more copy. 1777 * Set the truncate flag and return. 1778 */ 1779 nni6->ni_flags |= 1780 NI_NODEADDR_FLAG_TRUNCATE; 1781 return (copied); 1782 } 1783 1784 /* 1785 * Set the TTL of the address. 1786 * The TTL value should be one of the following 1787 * according to the specification: 1788 * 1789 * 1. The remaining lifetime of a DHCP lease on the 1790 * address, or 1791 * 2. The remaining Valid Lifetime of a prefix from 1792 * which the address was derived through Stateless 1793 * Autoconfiguration. 1794 * 1795 * Note that we currently do not support stateful 1796 * address configuration by DHCPv6, so the former 1797 * case can't happen. 1798 */ 1799 if (ifa6->ia6_lifetime.ia6t_expire == 0) 1800 ltime = ND6_INFINITE_LIFETIME; 1801 else { 1802 if (ifa6->ia6_lifetime.ia6t_expire > 1803 time_second) 1804 ltime = htonl(ifa6->ia6_lifetime.ia6t_expire - time_second); 1805 else 1806 ltime = 0; 1807 } 1808 1809 bcopy(<ime, cp, sizeof(u_int32_t)); 1810 cp += sizeof(u_int32_t); 1811 1812 /* copy the address itself */ 1813 bcopy(&ifa6->ia_addr.sin6_addr, cp, 1814 sizeof(struct in6_addr)); 1815 /* XXX: KAME link-local hack; remove ifindex */ 1816 if (IN6_IS_ADDR_LINKLOCAL(&ifa6->ia_addr.sin6_addr)) 1817 ((struct in6_addr *)cp)->s6_addr16[1] = 0; 1818 cp += sizeof(struct in6_addr); 1819 1820 resid -= (sizeof(struct in6_addr) + sizeof(u_int32_t)); 1821 copied += (sizeof(struct in6_addr) + 1822 sizeof(u_int32_t)); 1823 } 1824 if (ifp0) /* we need search only on the specified IF */ 1825 break; 1826 } 1827 1828 if (allow_deprecated == 0 && ifp_dep != NULL) { 1829 ifp = ifp_dep; 1830 allow_deprecated = 1; 1831 1832 goto again; 1833 } 1834 1835 return (copied); 1836 } 1837 1838 /* 1839 * XXX almost dup'ed code with rip6_input. 1840 */ 1841 static int 1842 icmp6_rip6_input(struct mbuf **mp, int off) 1843 { 1844 struct mbuf *m = *mp; 1845 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1846 struct in6pcb *in6p; 1847 struct in6pcb *last = NULL; 1848 struct sockaddr_in6 rip6src; 1849 struct icmp6_hdr *icmp6; 1850 struct mbuf *opts = NULL; 1851 1852 #ifndef PULLDOWN_TEST 1853 /* this is assumed to be safe. */ 1854 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off); 1855 #else 1856 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 1857 if (icmp6 == NULL) { 1858 /* m is already reclaimed */ 1859 return IPPROTO_DONE; 1860 } 1861 #endif 1862 1863 bzero(&rip6src, sizeof(rip6src)); 1864 rip6src.sin6_len = sizeof(struct sockaddr_in6); 1865 rip6src.sin6_family = AF_INET6; 1866 /* KAME hack: recover scopeid */ 1867 in6_recoverscope(&rip6src, &ip6->ip6_src, m->m_pkthdr.rcvif); 1868 1869 LIST_FOREACH(in6p, &ripcbinfo.pcblisthead, inp_list) 1870 { 1871 if (in6p->inp_flags & INP_PLACEMARKER) 1872 continue; 1873 if ((in6p->inp_vflag & INP_IPV6) == 0) 1874 continue; 1875 #ifdef HAVE_NRL_INPCB 1876 if (!(in6p->in6p_flags & INP_IPV6)) 1877 continue; 1878 #endif 1879 if (in6p->in6p_ip6_nxt != IPPROTO_ICMPV6) 1880 continue; 1881 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr) && 1882 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr, &ip6->ip6_dst)) 1883 continue; 1884 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr) && 1885 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr, &ip6->ip6_src)) 1886 continue; 1887 if (in6p->in6p_icmp6filt 1888 && ICMP6_FILTER_WILLBLOCK(icmp6->icmp6_type, 1889 in6p->in6p_icmp6filt)) 1890 continue; 1891 if (last) { 1892 struct mbuf *n; 1893 if ((n = m_copy(m, 0, (int)M_COPYALL)) != NULL) { 1894 if (last->in6p_flags & IN6P_CONTROLOPTS) 1895 ip6_savecontrol(last, &opts, ip6, n); 1896 /* strip intermediate headers */ 1897 m_adj(n, off); 1898 if (ssb_appendaddr(&last->in6p_socket->so_rcv, 1899 (struct sockaddr *)&rip6src, 1900 n, opts) == 0) { 1901 /* should notify about lost packet */ 1902 m_freem(n); 1903 if (opts) { 1904 m_freem(opts); 1905 } 1906 } else 1907 sorwakeup(last->in6p_socket); 1908 opts = NULL; 1909 } 1910 } 1911 last = in6p; 1912 } 1913 if (last) { 1914 if (last->in6p_flags & IN6P_CONTROLOPTS) 1915 ip6_savecontrol(last, &opts, ip6, m); 1916 /* strip intermediate headers */ 1917 m_adj(m, off); 1918 if (ssb_appendaddr(&last->in6p_socket->so_rcv, 1919 (struct sockaddr *)&rip6src, m, opts) == 0) { 1920 m_freem(m); 1921 if (opts) 1922 m_freem(opts); 1923 } else 1924 sorwakeup(last->in6p_socket); 1925 } else { 1926 m_freem(m); 1927 ip6stat.ip6s_delivered--; 1928 } 1929 return IPPROTO_DONE; 1930 } 1931 1932 /* 1933 * Reflect the ip6 packet back to the source. 1934 * OFF points to the icmp6 header, counted from the top of the mbuf. 1935 */ 1936 void 1937 icmp6_reflect(struct mbuf *m, size_t off) 1938 { 1939 struct ip6_hdr *ip6; 1940 struct icmp6_hdr *icmp6; 1941 struct in6_ifaddr *ia; 1942 struct in6_addr t, *src = 0; 1943 int plen; 1944 int type, code; 1945 struct ifnet *outif = NULL; 1946 struct sockaddr_in6 sa6_src, sa6_dst; 1947 #ifdef COMPAT_RFC1885 1948 int mtu = IPV6_MMTU; 1949 struct sockaddr_in6 *sin6 = &icmp6_reflect_rt.ro_dst; 1950 #endif 1951 1952 /* too short to reflect */ 1953 if (off < sizeof(struct ip6_hdr)) { 1954 nd6log((LOG_DEBUG, 1955 "sanity fail: off=%lx, sizeof(ip6)=%lx in %s:%d\n", 1956 (u_long)off, (u_long)sizeof(struct ip6_hdr), 1957 __FILE__, __LINE__)); 1958 goto bad; 1959 } 1960 1961 /* 1962 * If there are extra headers between IPv6 and ICMPv6, strip 1963 * off that header first. 1964 */ 1965 #ifdef DIAGNOSTIC 1966 if (sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) > MHLEN) 1967 panic("assumption failed in icmp6_reflect"); 1968 #endif 1969 if (off > sizeof(struct ip6_hdr)) { 1970 size_t l; 1971 struct ip6_hdr nip6; 1972 1973 l = off - sizeof(struct ip6_hdr); 1974 m_copydata(m, 0, sizeof(nip6), (caddr_t)&nip6); 1975 m_adj(m, l); 1976 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 1977 if (m->m_len < l) { 1978 if ((m = m_pullup(m, l)) == NULL) 1979 return; 1980 } 1981 bcopy((caddr_t)&nip6, mtod(m, caddr_t), sizeof(nip6)); 1982 } else /* off == sizeof(struct ip6_hdr) */ { 1983 size_t l; 1984 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 1985 if (m->m_len < l) { 1986 if ((m = m_pullup(m, l)) == NULL) 1987 return; 1988 } 1989 } 1990 plen = m->m_pkthdr.len - sizeof(struct ip6_hdr); 1991 ip6 = mtod(m, struct ip6_hdr *); 1992 ip6->ip6_nxt = IPPROTO_ICMPV6; 1993 icmp6 = (struct icmp6_hdr *)(ip6 + 1); 1994 type = icmp6->icmp6_type; /* keep type for statistics */ 1995 code = icmp6->icmp6_code; /* ditto. */ 1996 1997 t = ip6->ip6_dst; 1998 /* 1999 * ip6_input() drops a packet if its src is multicast. 2000 * So, the src is never multicast. 2001 */ 2002 ip6->ip6_dst = ip6->ip6_src; 2003 2004 /* 2005 * XXX: make sure to embed scope zone information, using 2006 * already embedded IDs or the received interface (if any). 2007 * Note that rcvif may be NULL. 2008 * TODO: scoped routing case (XXX). 2009 */ 2010 bzero(&sa6_src, sizeof(sa6_src)); 2011 sa6_src.sin6_family = AF_INET6; 2012 sa6_src.sin6_len = sizeof(sa6_src); 2013 sa6_src.sin6_addr = ip6->ip6_dst; 2014 in6_recoverscope(&sa6_src, &ip6->ip6_dst, m->m_pkthdr.rcvif); 2015 in6_embedscope(&ip6->ip6_dst, &sa6_src, NULL, NULL); 2016 bzero(&sa6_dst, sizeof(sa6_dst)); 2017 sa6_dst.sin6_family = AF_INET6; 2018 sa6_dst.sin6_len = sizeof(sa6_dst); 2019 sa6_dst.sin6_addr = t; 2020 in6_recoverscope(&sa6_dst, &t, m->m_pkthdr.rcvif); 2021 in6_embedscope(&t, &sa6_dst, NULL, NULL); 2022 2023 #ifdef COMPAT_RFC1885 2024 /* 2025 * xxx guess MTU 2026 * RFC 1885 requires that echo reply should be truncated if it 2027 * does not fit in with (return) path MTU, but the description was 2028 * removed in the new spec. 2029 */ 2030 if (icmp6_reflect_rt.ro_rt == 0 || 2031 ! (IN6_ARE_ADDR_EQUAL(&sin6->sin6_addr, &ip6->ip6_dst))) { 2032 if (icmp6_reflect_rt.ro_rt) { 2033 RTFREE(icmp6_reflect_rt.ro_rt); 2034 icmp6_reflect_rt.ro_rt = 0; 2035 } 2036 bzero(sin6, sizeof(*sin6)); 2037 sin6->sin6_family = PF_INET6; 2038 sin6->sin6_len = sizeof(struct sockaddr_in6); 2039 sin6->sin6_addr = ip6->ip6_dst; 2040 2041 rtalloc_ign((struct route *)&icmp6_reflect_rt.ro_rt, 2042 RTF_PRCLONING); 2043 } 2044 2045 if (icmp6_reflect_rt.ro_rt == 0) 2046 goto bad; 2047 2048 if ((icmp6_reflect_rt.ro_rt->rt_flags & RTF_HOST) 2049 && mtu < icmp6_reflect_rt.ro_rt->rt_ifp->if_mtu) 2050 mtu = icmp6_reflect_rt.ro_rt->rt_rmx.rmx_mtu; 2051 2052 if (mtu < m->m_pkthdr.len) { 2053 plen -= (m->m_pkthdr.len - mtu); 2054 m_adj(m, mtu - m->m_pkthdr.len); 2055 } 2056 #endif 2057 /* 2058 * If the incoming packet was addressed directly to us(i.e. unicast), 2059 * use dst as the src for the reply. 2060 * The IN6_IFF_NOTREADY case would be VERY rare, but is possible 2061 * (for example) when we encounter an error while forwarding procedure 2062 * destined to a duplicated address of ours. 2063 */ 2064 for (ia = in6_ifaddr; ia; ia = ia->ia_next) 2065 if (IN6_ARE_ADDR_EQUAL(&t, &ia->ia_addr.sin6_addr) && 2066 (ia->ia6_flags & (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY)) == 0) { 2067 src = &t; 2068 break; 2069 } 2070 if (ia == NULL && IN6_IS_ADDR_LINKLOCAL(&t) && (m->m_flags & M_LOOP)) { 2071 /* 2072 * This is the case if the dst is our link-local address 2073 * and the sender is also ourselves. 2074 */ 2075 src = &t; 2076 } 2077 2078 if (src == 0) { 2079 int e; 2080 struct route_in6 ro; 2081 2082 /* 2083 * This case matches to multicasts, our anycast, or unicasts 2084 * that we do not own. Select a source address based on the 2085 * source address of the erroneous packet. 2086 */ 2087 bzero(&ro, sizeof(ro)); 2088 src = in6_selectsrc(&sa6_src, NULL, NULL, &ro, NULL, &e, NULL); 2089 if (ro.ro_rt) 2090 RTFREE(ro.ro_rt); /* XXX: we could use this */ 2091 if (src == NULL) { 2092 nd6log((LOG_DEBUG, 2093 "icmp6_reflect: source can't be determined: " 2094 "dst=%s, error=%d\n", 2095 ip6_sprintf(&sa6_src.sin6_addr), e)); 2096 goto bad; 2097 } 2098 } 2099 2100 ip6->ip6_src = *src; 2101 2102 ip6->ip6_flow = 0; 2103 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2104 ip6->ip6_vfc |= IPV6_VERSION; 2105 ip6->ip6_nxt = IPPROTO_ICMPV6; 2106 if (m->m_pkthdr.rcvif) { 2107 /* XXX: This may not be the outgoing interface */ 2108 ip6->ip6_hlim = ND_IFINFO(m->m_pkthdr.rcvif)->chlim; 2109 } else 2110 ip6->ip6_hlim = ip6_defhlim; 2111 2112 icmp6->icmp6_cksum = 0; 2113 icmp6->icmp6_cksum = in6_cksum(m, IPPROTO_ICMPV6, 2114 sizeof(struct ip6_hdr), plen); 2115 2116 /* 2117 * XXX option handling 2118 */ 2119 2120 m->m_flags &= ~(M_BCAST|M_MCAST); 2121 2122 #ifdef COMPAT_RFC1885 2123 ip6_output(m, NULL, &icmp6_reflect_rt, 0, NULL, &outif, NULL); 2124 #else 2125 ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL); 2126 #endif 2127 if (outif) 2128 icmp6_ifoutstat_inc(outif, type, code); 2129 2130 return; 2131 2132 bad: 2133 m_freem(m); 2134 return; 2135 } 2136 2137 void 2138 icmp6_fasttimo(void) 2139 { 2140 2141 mld6_fasttimeo(); 2142 } 2143 2144 static const char * 2145 icmp6_redirect_diag(struct in6_addr *src6, struct in6_addr *dst6, 2146 struct in6_addr *tgt6) 2147 { 2148 static char buf[1024]; 2149 ksnprintf(buf, sizeof(buf), "(src=%s dst=%s tgt=%s)", 2150 ip6_sprintf(src6), ip6_sprintf(dst6), ip6_sprintf(tgt6)); 2151 return buf; 2152 } 2153 2154 void 2155 icmp6_redirect_input(struct mbuf *m, int off) 2156 { 2157 struct ifnet *ifp = m->m_pkthdr.rcvif; 2158 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 2159 struct nd_redirect *nd_rd; 2160 int icmp6len = ntohs(ip6->ip6_plen); 2161 char *lladdr = NULL; 2162 int lladdrlen = 0; 2163 u_char *redirhdr = NULL; 2164 int redirhdrlen = 0; 2165 struct rtentry *rt = NULL; 2166 int is_router; 2167 int is_onlink; 2168 struct in6_addr src6 = ip6->ip6_src; 2169 struct in6_addr redtgt6; 2170 struct in6_addr reddst6; 2171 union nd_opts ndopts; 2172 2173 if (!m || !ifp) 2174 return; 2175 2176 /* XXX if we are router, we don't update route by icmp6 redirect */ 2177 if (ip6_forwarding) 2178 goto freeit; 2179 if (!icmp6_rediraccept) 2180 goto freeit; 2181 2182 #ifndef PULLDOWN_TEST 2183 IP6_EXTHDR_CHECK(m, off, icmp6len,); 2184 nd_rd = (struct nd_redirect *)((caddr_t)ip6 + off); 2185 #else 2186 IP6_EXTHDR_GET(nd_rd, struct nd_redirect *, m, off, icmp6len); 2187 if (nd_rd == NULL) { 2188 icmp6stat.icp6s_tooshort++; 2189 return; 2190 } 2191 #endif 2192 redtgt6 = nd_rd->nd_rd_target; 2193 reddst6 = nd_rd->nd_rd_dst; 2194 2195 if (IN6_IS_ADDR_LINKLOCAL(&redtgt6)) 2196 redtgt6.s6_addr16[1] = htons(ifp->if_index); 2197 if (IN6_IS_ADDR_LINKLOCAL(&reddst6)) 2198 reddst6.s6_addr16[1] = htons(ifp->if_index); 2199 2200 /* validation */ 2201 if (!IN6_IS_ADDR_LINKLOCAL(&src6)) { 2202 nd6log((LOG_ERR, 2203 "ICMP6 redirect sent from %s rejected; " 2204 "must be from linklocal\n", ip6_sprintf(&src6))); 2205 goto bad; 2206 } 2207 if (ip6->ip6_hlim != 255) { 2208 nd6log((LOG_ERR, 2209 "ICMP6 redirect sent from %s rejected; " 2210 "hlim=%d (must be 255)\n", 2211 ip6_sprintf(&src6), ip6->ip6_hlim)); 2212 goto bad; 2213 } 2214 { 2215 /* ip6->ip6_src must be equal to gw for icmp6->icmp6_reddst */ 2216 struct sockaddr_in6 sin6; 2217 struct in6_addr *gw6; 2218 2219 bzero(&sin6, sizeof(sin6)); 2220 sin6.sin6_family = AF_INET6; 2221 sin6.sin6_len = sizeof(struct sockaddr_in6); 2222 bcopy(&reddst6, &sin6.sin6_addr, sizeof reddst6); 2223 rt = rtpurelookup((struct sockaddr *)&sin6); 2224 if (rt != NULL) { 2225 if (rt->rt_gateway == NULL || 2226 rt->rt_gateway->sa_family != AF_INET6) { 2227 nd6log((LOG_ERR, 2228 "ICMP6 redirect rejected; no route " 2229 "with inet6 gateway found for redirect dst: %s\n", 2230 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2231 --rt->rt_refcnt; 2232 goto bad; 2233 } 2234 2235 gw6 = &(((struct sockaddr_in6 *)rt->rt_gateway)->sin6_addr); 2236 if (bcmp(&src6, gw6, sizeof(struct in6_addr)) != 0) { 2237 nd6log((LOG_ERR, 2238 "ICMP6 redirect rejected; " 2239 "not equal to gw-for-src=%s (must be same): " 2240 "%s\n", 2241 ip6_sprintf(gw6), 2242 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2243 --rt->rt_refcnt; 2244 goto bad; 2245 } 2246 } else { 2247 nd6log((LOG_ERR, 2248 "ICMP6 redirect rejected; " 2249 "no route found for redirect dst: %s\n", 2250 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2251 goto bad; 2252 } 2253 --rt->rt_refcnt; 2254 rt = NULL; 2255 } 2256 if (IN6_IS_ADDR_MULTICAST(&reddst6)) { 2257 nd6log((LOG_ERR, 2258 "ICMP6 redirect rejected; " 2259 "redirect dst must be unicast: %s\n", 2260 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2261 goto bad; 2262 } 2263 2264 is_router = is_onlink = 0; 2265 if (IN6_IS_ADDR_LINKLOCAL(&redtgt6)) 2266 is_router = 1; /* router case */ 2267 if (bcmp(&redtgt6, &reddst6, sizeof(redtgt6)) == 0) 2268 is_onlink = 1; /* on-link destination case */ 2269 if (!is_router && !is_onlink) { 2270 nd6log((LOG_ERR, 2271 "ICMP6 redirect rejected; " 2272 "neither router case nor onlink case: %s\n", 2273 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2274 goto bad; 2275 } 2276 /* validation passed */ 2277 2278 icmp6len -= sizeof(*nd_rd); 2279 nd6_option_init(nd_rd + 1, icmp6len, &ndopts); 2280 if (nd6_options(&ndopts) < 0) { 2281 nd6log((LOG_INFO, "icmp6_redirect_input: " 2282 "invalid ND option, rejected: %s\n", 2283 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2284 /* nd6_options have incremented stats */ 2285 goto freeit; 2286 } 2287 2288 if (ndopts.nd_opts_tgt_lladdr) { 2289 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 2290 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 2291 } 2292 2293 if (ndopts.nd_opts_rh) { 2294 redirhdrlen = ndopts.nd_opts_rh->nd_opt_rh_len; 2295 redirhdr = (u_char *)(ndopts.nd_opts_rh + 1); /* xxx */ 2296 } 2297 2298 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 2299 nd6log((LOG_INFO, 2300 "icmp6_redirect_input: lladdrlen mismatch for %s " 2301 "(if %d, icmp6 packet %d): %s\n", 2302 ip6_sprintf(&redtgt6), ifp->if_addrlen, lladdrlen - 2, 2303 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2304 goto bad; 2305 } 2306 2307 /* RFC 2461 8.3 */ 2308 nd6_cache_lladdr(ifp, &redtgt6, lladdr, lladdrlen, ND_REDIRECT, 2309 is_onlink ? ND_REDIRECT_ONLINK : ND_REDIRECT_ROUTER); 2310 2311 if (!is_onlink) { /* better router case. perform rtredirect. */ 2312 /* perform rtredirect */ 2313 struct sockaddr_in6 sdst; 2314 struct sockaddr_in6 sgw; 2315 struct sockaddr_in6 ssrc; 2316 2317 bzero(&sdst, sizeof(sdst)); 2318 bzero(&sgw, sizeof(sgw)); 2319 bzero(&ssrc, sizeof(ssrc)); 2320 sdst.sin6_family = sgw.sin6_family = ssrc.sin6_family = AF_INET6; 2321 sdst.sin6_len = sgw.sin6_len = ssrc.sin6_len = 2322 sizeof(struct sockaddr_in6); 2323 bcopy(&redtgt6, &sgw.sin6_addr, sizeof(struct in6_addr)); 2324 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2325 bcopy(&src6, &ssrc.sin6_addr, sizeof(struct in6_addr)); 2326 rtredirect((struct sockaddr *)&sdst, (struct sockaddr *)&sgw, 2327 (struct sockaddr *)NULL, RTF_GATEWAY | RTF_HOST, 2328 (struct sockaddr *)&ssrc); 2329 } 2330 /* finally update cached route in each socket via pfctlinput */ 2331 { 2332 struct sockaddr_in6 sdst; 2333 2334 bzero(&sdst, sizeof(sdst)); 2335 sdst.sin6_family = AF_INET6; 2336 sdst.sin6_len = sizeof(struct sockaddr_in6); 2337 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2338 pfctlinput(PRC_REDIRECT_HOST, (struct sockaddr *)&sdst); 2339 #ifdef IPSEC 2340 key_sa_routechange((struct sockaddr *)&sdst); 2341 #endif 2342 } 2343 2344 freeit: 2345 m_freem(m); 2346 return; 2347 2348 bad: 2349 icmp6stat.icp6s_badredirect++; 2350 m_freem(m); 2351 } 2352 2353 void 2354 icmp6_redirect_output(struct mbuf *m0, struct rtentry *rt) 2355 { 2356 struct ifnet *ifp; /* my outgoing interface */ 2357 struct in6_addr *ifp_ll6; 2358 struct in6_addr *router_ll6; 2359 struct ip6_hdr *sip6; /* m0 as struct ip6_hdr */ 2360 struct mbuf *m = NULL; /* newly allocated one */ 2361 struct ip6_hdr *ip6; /* m as struct ip6_hdr */ 2362 struct nd_redirect *nd_rd; 2363 size_t maxlen; 2364 u_char *p; 2365 struct ifnet *outif = NULL; 2366 struct sockaddr_in6 src_sa; 2367 2368 icmp6_errcount(&icmp6stat.icp6s_outerrhist, ND_REDIRECT, 0); 2369 2370 /* if we are not router, we don't send icmp6 redirect */ 2371 if (!ip6_forwarding || ip6_accept_rtadv) 2372 goto fail; 2373 2374 /* sanity check */ 2375 if (!m0 || !rt || !(rt->rt_flags & RTF_UP) || !(ifp = rt->rt_ifp)) 2376 goto fail; 2377 2378 /* 2379 * Address check: 2380 * the source address must identify a neighbor, and 2381 * the destination address must not be a multicast address 2382 * [RFC 2461, sec 8.2] 2383 */ 2384 sip6 = mtod(m0, struct ip6_hdr *); 2385 bzero(&src_sa, sizeof(src_sa)); 2386 src_sa.sin6_family = AF_INET6; 2387 src_sa.sin6_len = sizeof(src_sa); 2388 src_sa.sin6_addr = sip6->ip6_src; 2389 /* we don't currently use sin6_scope_id, but eventually use it */ 2390 src_sa.sin6_scope_id = in6_addr2scopeid(ifp, &sip6->ip6_src); 2391 if (nd6_is_addr_neighbor(&src_sa, ifp) == 0) 2392 goto fail; 2393 if (IN6_IS_ADDR_MULTICAST(&sip6->ip6_dst)) 2394 goto fail; /* what should we do here? */ 2395 2396 /* rate limit */ 2397 if (icmp6_ratelimit(&sip6->ip6_src, ND_REDIRECT, 0)) 2398 goto fail; 2399 2400 /* 2401 * Since we are going to append up to 1280 bytes (= IPV6_MMTU), 2402 * we almost always ask for an mbuf cluster for simplicity. 2403 * (MHLEN < IPV6_MMTU is almost always true) 2404 */ 2405 #if IPV6_MMTU >= MCLBYTES 2406 # error assumption failed about IPV6_MMTU and MCLBYTES 2407 #endif 2408 m = m_getb(IPV6_MMTU, MB_DONTWAIT, MT_HEADER, M_PKTHDR); 2409 if (!m) 2410 goto fail; 2411 m->m_len = 0; 2412 maxlen = M_TRAILINGSPACE(m); 2413 maxlen = min(IPV6_MMTU, maxlen); 2414 /* just for safety */ 2415 if (maxlen < sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) + 2416 ((sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7)) { 2417 goto fail; 2418 } 2419 2420 { 2421 /* get ip6 linklocal address for ifp(my outgoing interface). */ 2422 struct in6_ifaddr *ia; 2423 if ((ia = in6ifa_ifpforlinklocal(ifp, 2424 IN6_IFF_NOTREADY| 2425 IN6_IFF_ANYCAST)) == NULL) 2426 goto fail; 2427 ifp_ll6 = &ia->ia_addr.sin6_addr; 2428 } 2429 2430 /* get ip6 linklocal address for the router. */ 2431 if (rt->rt_gateway && (rt->rt_flags & RTF_GATEWAY)) { 2432 struct sockaddr_in6 *sin6; 2433 sin6 = (struct sockaddr_in6 *)rt->rt_gateway; 2434 router_ll6 = &sin6->sin6_addr; 2435 if (!IN6_IS_ADDR_LINKLOCAL(router_ll6)) 2436 router_ll6 = (struct in6_addr *)NULL; 2437 } else 2438 router_ll6 = (struct in6_addr *)NULL; 2439 2440 /* ip6 */ 2441 ip6 = mtod(m, struct ip6_hdr *); 2442 ip6->ip6_flow = 0; 2443 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2444 ip6->ip6_vfc |= IPV6_VERSION; 2445 /* ip6->ip6_plen will be set later */ 2446 ip6->ip6_nxt = IPPROTO_ICMPV6; 2447 ip6->ip6_hlim = 255; 2448 /* ip6->ip6_src must be linklocal addr for my outgoing if. */ 2449 bcopy(ifp_ll6, &ip6->ip6_src, sizeof(struct in6_addr)); 2450 bcopy(&sip6->ip6_src, &ip6->ip6_dst, sizeof(struct in6_addr)); 2451 2452 /* ND Redirect */ 2453 nd_rd = (struct nd_redirect *)(ip6 + 1); 2454 nd_rd->nd_rd_type = ND_REDIRECT; 2455 nd_rd->nd_rd_code = 0; 2456 nd_rd->nd_rd_reserved = 0; 2457 if (rt->rt_flags & RTF_GATEWAY) { 2458 /* 2459 * nd_rd->nd_rd_target must be a link-local address in 2460 * better router cases. 2461 */ 2462 if (!router_ll6) 2463 goto fail; 2464 bcopy(router_ll6, &nd_rd->nd_rd_target, 2465 sizeof(nd_rd->nd_rd_target)); 2466 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2467 sizeof(nd_rd->nd_rd_dst)); 2468 } else { 2469 /* make sure redtgt == reddst */ 2470 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_target, 2471 sizeof(nd_rd->nd_rd_target)); 2472 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2473 sizeof(nd_rd->nd_rd_dst)); 2474 } 2475 2476 p = (u_char *)(nd_rd + 1); 2477 2478 if (!router_ll6) 2479 goto nolladdropt; 2480 2481 { 2482 /* target lladdr option */ 2483 struct rtentry *rt_router = NULL; 2484 int len; 2485 struct sockaddr_dl *sdl; 2486 struct nd_opt_hdr *nd_opt; 2487 char *lladdr; 2488 2489 rt_router = nd6_lookup(router_ll6, 0, ifp); 2490 if (!rt_router) 2491 goto nolladdropt; 2492 len = sizeof(*nd_opt) + ifp->if_addrlen; 2493 len = (len + 7) & ~7; /* round by 8 */ 2494 /* safety check */ 2495 if (len + (p - (u_char *)ip6) > maxlen) 2496 goto nolladdropt; 2497 if (!(rt_router->rt_flags & RTF_GATEWAY) && 2498 (rt_router->rt_flags & RTF_LLINFO) && 2499 (rt_router->rt_gateway->sa_family == AF_LINK) && 2500 (sdl = (struct sockaddr_dl *)rt_router->rt_gateway) && 2501 sdl->sdl_alen) { 2502 nd_opt = (struct nd_opt_hdr *)p; 2503 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 2504 nd_opt->nd_opt_len = len >> 3; 2505 lladdr = (char *)(nd_opt + 1); 2506 bcopy(LLADDR(sdl), lladdr, ifp->if_addrlen); 2507 p += len; 2508 } 2509 } 2510 nolladdropt:; 2511 2512 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2513 2514 /* just to be safe */ 2515 #ifdef M_DECRYPTED /*not openbsd*/ 2516 if (m0->m_flags & M_DECRYPTED) 2517 goto noredhdropt; 2518 #endif 2519 if (p - (u_char *)ip6 > maxlen) 2520 goto noredhdropt; 2521 2522 { 2523 /* redirected header option */ 2524 int len; 2525 struct nd_opt_rd_hdr *nd_opt_rh; 2526 2527 /* 2528 * compute the maximum size for icmp6 redirect header option. 2529 * XXX room for auth header? 2530 */ 2531 len = maxlen - (p - (u_char *)ip6); 2532 len &= ~7; 2533 2534 /* This is just for simplicity. */ 2535 if (m0->m_pkthdr.len != m0->m_len) { 2536 if (m0->m_next) { 2537 m_freem(m0->m_next); 2538 m0->m_next = NULL; 2539 } 2540 m0->m_pkthdr.len = m0->m_len; 2541 } 2542 2543 /* 2544 * Redirected header option spec (RFC2461 4.6.3) talks nothing 2545 * about padding/truncate rule for the original IP packet. 2546 * From the discussion on IPv6imp in Feb 1999, the consensus was: 2547 * - "attach as much as possible" is the goal 2548 * - pad if not aligned (original size can be guessed by original 2549 * ip6 header) 2550 * Following code adds the padding if it is simple enough, 2551 * and truncates if not. 2552 */ 2553 if (m0->m_next || m0->m_pkthdr.len != m0->m_len) 2554 panic("assumption failed in %s:%d", __FILE__, __LINE__); 2555 2556 if (len - sizeof(*nd_opt_rh) < m0->m_pkthdr.len) { 2557 /* not enough room, truncate */ 2558 m0->m_pkthdr.len = m0->m_len = len - sizeof(*nd_opt_rh); 2559 } else { 2560 /* enough room, pad or truncate */ 2561 size_t extra; 2562 2563 extra = m0->m_pkthdr.len % 8; 2564 if (extra) { 2565 /* pad if easy enough, truncate if not */ 2566 if (8 - extra <= M_TRAILINGSPACE(m0)) { 2567 /* pad */ 2568 m0->m_len += (8 - extra); 2569 m0->m_pkthdr.len += (8 - extra); 2570 } else { 2571 /* truncate */ 2572 m0->m_pkthdr.len -= extra; 2573 m0->m_len -= extra; 2574 } 2575 } 2576 len = m0->m_pkthdr.len + sizeof(*nd_opt_rh); 2577 m0->m_pkthdr.len = m0->m_len = len - sizeof(*nd_opt_rh); 2578 } 2579 2580 nd_opt_rh = (struct nd_opt_rd_hdr *)p; 2581 bzero(nd_opt_rh, sizeof(*nd_opt_rh)); 2582 nd_opt_rh->nd_opt_rh_type = ND_OPT_REDIRECTED_HEADER; 2583 nd_opt_rh->nd_opt_rh_len = len >> 3; 2584 p += sizeof(*nd_opt_rh); 2585 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2586 2587 /* connect m0 to m */ 2588 m->m_next = m0; 2589 m->m_pkthdr.len = m->m_len + m0->m_len; 2590 } 2591 noredhdropt:; 2592 2593 if (IN6_IS_ADDR_LINKLOCAL(&sip6->ip6_src)) 2594 sip6->ip6_src.s6_addr16[1] = 0; 2595 if (IN6_IS_ADDR_LINKLOCAL(&sip6->ip6_dst)) 2596 sip6->ip6_dst.s6_addr16[1] = 0; 2597 #if 0 2598 if (IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_src)) 2599 ip6->ip6_src.s6_addr16[1] = 0; 2600 if (IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_dst)) 2601 ip6->ip6_dst.s6_addr16[1] = 0; 2602 #endif 2603 if (IN6_IS_ADDR_LINKLOCAL(&nd_rd->nd_rd_target)) 2604 nd_rd->nd_rd_target.s6_addr16[1] = 0; 2605 if (IN6_IS_ADDR_LINKLOCAL(&nd_rd->nd_rd_dst)) 2606 nd_rd->nd_rd_dst.s6_addr16[1] = 0; 2607 2608 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr)); 2609 2610 nd_rd->nd_rd_cksum = 0; 2611 nd_rd->nd_rd_cksum 2612 = in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), ntohs(ip6->ip6_plen)); 2613 2614 /* send the packet to outside... */ 2615 ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL); 2616 if (outif) { 2617 icmp6_ifstat_inc(outif, ifs6_out_msg); 2618 icmp6_ifstat_inc(outif, ifs6_out_redirect); 2619 } 2620 icmp6stat.icp6s_outhist[ND_REDIRECT]++; 2621 2622 return; 2623 2624 fail: 2625 if (m) 2626 m_freem(m); 2627 if (m0) 2628 m_freem(m0); 2629 } 2630 2631 #ifdef HAVE_NRL_INPCB 2632 #define in6pcb inpcb 2633 #define in6p_icmp6filt inp_icmp6filt 2634 #endif 2635 /* 2636 * ICMPv6 socket option processing. 2637 */ 2638 int 2639 icmp6_ctloutput(struct socket *so, struct sockopt *sopt) 2640 { 2641 int error = 0; 2642 int optlen; 2643 struct inpcb *inp = so->so_pcb; 2644 int level, op, optname; 2645 2646 if (sopt) { 2647 level = sopt->sopt_level; 2648 op = sopt->sopt_dir; 2649 optname = sopt->sopt_name; 2650 optlen = sopt->sopt_valsize; 2651 } else 2652 level = op = optname = optlen = 0; 2653 2654 if (level != IPPROTO_ICMPV6) { 2655 return EINVAL; 2656 } 2657 2658 switch (op) { 2659 case PRCO_SETOPT: 2660 switch (optname) { 2661 case ICMP6_FILTER: 2662 { 2663 struct icmp6_filter *p; 2664 2665 if (optlen != sizeof(*p)) { 2666 error = EMSGSIZE; 2667 break; 2668 } 2669 if (inp->in6p_icmp6filt == NULL) { 2670 error = EINVAL; 2671 break; 2672 } 2673 error = sooptcopyin(sopt, inp->in6p_icmp6filt, optlen, 2674 optlen); 2675 break; 2676 } 2677 2678 default: 2679 error = ENOPROTOOPT; 2680 break; 2681 } 2682 break; 2683 2684 case PRCO_GETOPT: 2685 switch (optname) { 2686 case ICMP6_FILTER: 2687 { 2688 if (inp->in6p_icmp6filt == NULL) { 2689 error = EINVAL; 2690 break; 2691 } 2692 error = sooptcopyout(sopt, inp->in6p_icmp6filt, 2693 sizeof(struct icmp6_filter)); 2694 break; 2695 } 2696 2697 default: 2698 error = ENOPROTOOPT; 2699 break; 2700 } 2701 break; 2702 } 2703 2704 return (error); 2705 } 2706 #ifdef HAVE_NRL_INPCB 2707 #undef in6pcb 2708 #undef in6p_icmp6filt 2709 #endif 2710 2711 #ifndef HAVE_PPSRATECHECK 2712 #ifndef timersub 2713 #define timersub(tvp, uvp, vvp) \ 2714 do { \ 2715 (vvp)->tv_sec = (tvp)->tv_sec - (uvp)->tv_sec; \ 2716 (vvp)->tv_usec = (tvp)->tv_usec - (uvp)->tv_usec; \ 2717 if ((vvp)->tv_usec < 0) { \ 2718 (vvp)->tv_sec--; \ 2719 (vvp)->tv_usec += 1000000; \ 2720 } \ 2721 } while (0) 2722 #endif 2723 2724 /* 2725 * ppsratecheck(): packets (or events) per second limitation. 2726 */ 2727 static int 2728 ppsratecheck(struct timeval *lasttime, int *curpps, 2729 int maxpps) /* maximum pps allowed */ 2730 { 2731 struct timeval tv, delta; 2732 int rv; 2733 2734 microtime(&tv); 2735 2736 timersub(&tv, lasttime, &delta); 2737 2738 /* 2739 * Check for 0,0 so that the message will be seen at least once. 2740 * If more than one second has passed since the last update of 2741 * lasttime, reset the counter. 2742 * 2743 * We do increment *curpps even in *curpps < maxpps case, as some may 2744 * try to use *curpps for stat purposes as well. 2745 */ 2746 if ((lasttime->tv_sec == 0 && lasttime->tv_usec == 0) || 2747 delta.tv_sec >= 1) { 2748 *lasttime = tv; 2749 *curpps = 0; 2750 rv = 1; 2751 } else if (maxpps < 0) 2752 rv = 1; 2753 else if (*curpps < maxpps) 2754 rv = 1; 2755 else 2756 rv = 0; 2757 2758 #if 1 /* DIAGNOSTIC? */ 2759 /* be careful about wrap-around */ 2760 if (*curpps + 1 > *curpps) 2761 *curpps = *curpps + 1; 2762 #else 2763 /* 2764 * assume that there's not too many calls to this function. 2765 * not sure if the assumption holds, as it depends on *caller's* 2766 * behavior, not the behavior of this function. 2767 * IMHO it is wrong to make assumption on the caller's behavior, 2768 * so the above #if is #if 1, not #ifdef DIAGNOSTIC. 2769 */ 2770 *curpps = *curpps + 1; 2771 #endif 2772 2773 return (rv); 2774 } 2775 #endif 2776 2777 /* 2778 * Perform rate limit check. 2779 * Returns 0 if it is okay to send the icmp6 packet. 2780 * Returns 1 if the router SHOULD NOT send this icmp6 packet due to rate 2781 * limitation. 2782 * 2783 * XXX per-destination/type check necessary? 2784 */ 2785 static int 2786 icmp6_ratelimit(const struct in6_addr *dst, /* not used at this moment */ 2787 const int type, /* not used at this moment */ 2788 const int code) /* not used at this moment */ 2789 { 2790 int ret; 2791 2792 ret = 0; /* okay to send */ 2793 2794 /* PPS limit */ 2795 if (!ppsratecheck(&icmp6errppslim_last, &icmp6errpps_count, 2796 icmp6errppslim)) { 2797 /* The packet is subject to rate limit */ 2798 ret++; 2799 } 2800 2801 return ret; 2802 } 2803