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 1.31 2008/10/27 02:56:30 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/socketops.h> 81 #include <sys/time.h> 82 #include <sys/kernel.h> 83 #include <sys/syslog.h> 84 #include <sys/domain.h> 85 86 #include <net/if.h> 87 #include <net/route.h> 88 #include <net/if_dl.h> 89 #include <net/if_types.h> 90 91 #include <netinet/in.h> 92 #include <netinet/in_var.h> 93 #include <netinet/ip6.h> 94 #include <netinet6/ip6_var.h> 95 #include <netinet/icmp6.h> 96 #include <netinet6/mld6_var.h> 97 #include <netinet/in_pcb.h> 98 #include <netinet6/in6_pcb.h> 99 #include <netinet6/nd6.h> 100 #include <netinet6/in6_ifattach.h> 101 #include <netinet6/ip6protosw.h> 102 103 #ifdef IPSEC 104 #include <netinet6/ipsec.h> 105 #include <netproto/key/key.h> 106 #endif 107 108 #ifdef FAST_IPSEC 109 #include <netproto/ipsec/ipsec.h> 110 #include <netproto/ipsec/key.h> 111 #define IPSEC 112 #endif 113 114 #include <net/net_osdep.h> 115 116 #ifdef HAVE_NRL_INPCB 117 /* inpcb members */ 118 #define in6pcb inpcb 119 #define in6p_laddr inp_laddr6 120 #define in6p_faddr inp_faddr6 121 #define in6p_icmp6filt inp_icmp6filt 122 #define in6p_route inp_route 123 #define in6p_socket inp_socket 124 #define in6p_flags inp_flags 125 #define in6p_moptions inp_moptions6 126 #define in6p_outputopts inp_outputopts6 127 #define in6p_ip6 inp_ipv6 128 #define in6p_flowinfo inp_flowinfo 129 #define in6p_sp inp_sp 130 #define in6p_next inp_next 131 #define in6p_prev inp_prev 132 /* function names */ 133 #define in6_pcbdetach in_pcbdetach 134 #define in6_rtchange in_rtchange 135 136 /* 137 * for KAME src sync over BSD*'s. XXX: FreeBSD (>=3) are VERY different from 138 * others... 139 */ 140 #define in6p_ip6_nxt inp_ipv6.ip6_nxt 141 #endif 142 143 /* 144 * ppratecheck() is available, so define it here. 145 */ 146 #define HAVE_PPSRATECHECK 147 148 extern struct domain inet6domain; 149 extern struct ip6protosw inet6sw[]; 150 extern u_char ip6_protox[]; 151 152 struct icmp6stat icmp6stat; 153 154 extern struct inpcbinfo ripcbinfo; 155 extern int icmp6errppslim; 156 static int icmp6errpps_count = 0; 157 static struct timeval icmp6errppslim_last; 158 extern int icmp6_nodeinfo; 159 160 static void icmp6_errcount (struct icmp6errstat *, int, int); 161 static int icmp6_rip6_input (struct mbuf **, int); 162 static int icmp6_ratelimit (const struct in6_addr *, const int, const int); 163 static const char *icmp6_redirect_diag (struct in6_addr *, 164 struct in6_addr *, struct in6_addr *); 165 #ifndef HAVE_PPSRATECHECK 166 static int ppsratecheck (struct timeval *, int *, int); 167 #endif 168 static struct mbuf *ni6_input (struct mbuf *, int); 169 static struct mbuf *ni6_nametodns (const char *, int, int); 170 static int ni6_dnsmatch (const char *, int, const char *, int); 171 static int ni6_addrs (struct icmp6_nodeinfo *, struct mbuf *, 172 struct ifnet **, char *); 173 static int ni6_store_addrs (struct icmp6_nodeinfo *, struct icmp6_nodeinfo *, 174 struct ifnet *, int); 175 static int icmp6_notify_error (struct mbuf *, int, int, int); 176 177 #ifdef COMPAT_RFC1885 178 static struct route_in6 icmp6_reflect_rt; 179 #endif 180 181 182 void 183 icmp6_init(void) 184 { 185 mld6_init(); 186 } 187 188 static void 189 icmp6_errcount(struct icmp6errstat *stat, int type, int code) 190 { 191 switch (type) { 192 case ICMP6_DST_UNREACH: 193 switch (code) { 194 case ICMP6_DST_UNREACH_NOROUTE: 195 stat->icp6errs_dst_unreach_noroute++; 196 return; 197 case ICMP6_DST_UNREACH_ADMIN: 198 stat->icp6errs_dst_unreach_admin++; 199 return; 200 case ICMP6_DST_UNREACH_BEYONDSCOPE: 201 stat->icp6errs_dst_unreach_beyondscope++; 202 return; 203 case ICMP6_DST_UNREACH_ADDR: 204 stat->icp6errs_dst_unreach_addr++; 205 return; 206 case ICMP6_DST_UNREACH_NOPORT: 207 stat->icp6errs_dst_unreach_noport++; 208 return; 209 } 210 break; 211 case ICMP6_PACKET_TOO_BIG: 212 stat->icp6errs_packet_too_big++; 213 return; 214 case ICMP6_TIME_EXCEEDED: 215 switch (code) { 216 case ICMP6_TIME_EXCEED_TRANSIT: 217 stat->icp6errs_time_exceed_transit++; 218 return; 219 case ICMP6_TIME_EXCEED_REASSEMBLY: 220 stat->icp6errs_time_exceed_reassembly++; 221 return; 222 } 223 break; 224 case ICMP6_PARAM_PROB: 225 switch (code) { 226 case ICMP6_PARAMPROB_HEADER: 227 stat->icp6errs_paramprob_header++; 228 return; 229 case ICMP6_PARAMPROB_NEXTHEADER: 230 stat->icp6errs_paramprob_nextheader++; 231 return; 232 case ICMP6_PARAMPROB_OPTION: 233 stat->icp6errs_paramprob_option++; 234 return; 235 } 236 break; 237 case ND_REDIRECT: 238 stat->icp6errs_redirect++; 239 return; 240 } 241 stat->icp6errs_unknown++; 242 } 243 244 /* 245 * Generate an error packet of type error in response to bad IP6 packet. 246 */ 247 void 248 icmp6_error(struct mbuf *m, int type, int code, int 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, MB_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(struct mbuf **mp, int *offp, int proto) 396 { 397 struct mbuf *m = *mp, *n; 398 struct ip6_hdr *ip6, *nip6; 399 struct icmp6_hdr *icmp6, *nicmp6; 400 int off = *offp; 401 int icmp6len = m->m_pkthdr.len - *offp; 402 int code, sum, noff; 403 404 #ifndef PULLDOWN_TEST 405 IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_hdr), IPPROTO_DONE); 406 /* m might change if M_LOOP. So, call mtod after this */ 407 #endif 408 409 /* 410 * Locate icmp6 structure in mbuf, and check 411 * that not corrupted and of at least minimum length 412 */ 413 414 ip6 = mtod(m, struct ip6_hdr *); 415 if (icmp6len < sizeof(struct icmp6_hdr)) { 416 icmp6stat.icp6s_tooshort++; 417 goto freeit; 418 } 419 420 /* 421 * calculate the checksum 422 */ 423 #ifndef PULLDOWN_TEST 424 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off); 425 #else 426 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 427 if (icmp6 == NULL) { 428 icmp6stat.icp6s_tooshort++; 429 return IPPROTO_DONE; 430 } 431 #endif 432 code = icmp6->icmp6_code; 433 434 if ((sum = in6_cksum(m, IPPROTO_ICMPV6, off, icmp6len)) != 0) { 435 nd6log((LOG_ERR, 436 "ICMP6 checksum error(%d|%x) %s\n", 437 icmp6->icmp6_type, sum, ip6_sprintf(&ip6->ip6_src))); 438 icmp6stat.icp6s_checksum++; 439 goto freeit; 440 } 441 442 if (faithprefix_p != NULL && (*faithprefix_p)(&ip6->ip6_dst)) { 443 /* 444 * Deliver very specific ICMP6 type only. 445 * This is important to deilver TOOBIG. Otherwise PMTUD 446 * will not work. 447 */ 448 switch (icmp6->icmp6_type) { 449 case ICMP6_DST_UNREACH: 450 case ICMP6_PACKET_TOO_BIG: 451 case ICMP6_TIME_EXCEEDED: 452 break; 453 default: 454 goto freeit; 455 } 456 } 457 458 icmp6stat.icp6s_inhist[icmp6->icmp6_type]++; 459 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_msg); 460 if (icmp6->icmp6_type < ICMP6_INFOMSG_MASK) 461 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_error); 462 463 switch (icmp6->icmp6_type) { 464 case ICMP6_DST_UNREACH: 465 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_dstunreach); 466 switch (code) { 467 case ICMP6_DST_UNREACH_NOROUTE: 468 code = PRC_UNREACH_NET; 469 break; 470 case ICMP6_DST_UNREACH_ADMIN: 471 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_adminprohib); 472 code = PRC_UNREACH_PROTOCOL; /* is this a good code? */ 473 break; 474 case ICMP6_DST_UNREACH_ADDR: 475 code = PRC_HOSTDEAD; 476 break; 477 #ifdef COMPAT_RFC1885 478 case ICMP6_DST_UNREACH_NOTNEIGHBOR: 479 code = PRC_UNREACH_SRCFAIL; 480 break; 481 #else 482 case ICMP6_DST_UNREACH_BEYONDSCOPE: 483 /* I mean "source address was incorrect." */ 484 code = PRC_PARAMPROB; 485 break; 486 #endif 487 case ICMP6_DST_UNREACH_NOPORT: 488 code = PRC_UNREACH_PORT; 489 break; 490 default: 491 goto badcode; 492 } 493 goto deliver; 494 break; 495 496 case ICMP6_PACKET_TOO_BIG: 497 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_pkttoobig); 498 if (code != 0) 499 goto badcode; 500 501 code = PRC_MSGSIZE; 502 503 /* 504 * Updating the path MTU will be done after examining 505 * intermediate extension headers. 506 */ 507 goto deliver; 508 break; 509 510 case ICMP6_TIME_EXCEEDED: 511 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_timeexceed); 512 switch (code) { 513 case ICMP6_TIME_EXCEED_TRANSIT: 514 case ICMP6_TIME_EXCEED_REASSEMBLY: 515 code += PRC_TIMXCEED_INTRANS; 516 break; 517 default: 518 goto badcode; 519 } 520 goto deliver; 521 break; 522 523 case ICMP6_PARAM_PROB: 524 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_paramprob); 525 switch (code) { 526 case ICMP6_PARAMPROB_NEXTHEADER: 527 code = PRC_UNREACH_PROTOCOL; 528 break; 529 case ICMP6_PARAMPROB_HEADER: 530 case ICMP6_PARAMPROB_OPTION: 531 code = PRC_PARAMPROB; 532 break; 533 default: 534 goto badcode; 535 } 536 goto deliver; 537 break; 538 539 case ICMP6_ECHO_REQUEST: 540 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echo); 541 if (code != 0) 542 goto badcode; 543 if ((n = m_copy(m, 0, M_COPYALL)) == NULL) { 544 /* Give up remote */ 545 break; 546 } 547 if ((n->m_flags & M_EXT) || 548 n->m_len < off + sizeof(struct icmp6_hdr)) { 549 struct mbuf *n0 = n; 550 const int maxlen = sizeof(*nip6) + sizeof(*nicmp6); 551 int n0len; 552 553 /* 554 * Prepare an internal mbuf. m_pullup() doesn't 555 * always copy the length we specified. 556 */ 557 if (maxlen >= MCLBYTES) { 558 /* Give up remote */ 559 m_freem(n0); 560 break; 561 } 562 n = m_getb(maxlen, MB_DONTWAIT, n0->m_type, M_PKTHDR); 563 if (n == NULL) { 564 /* Give up remote */ 565 m_freem(n0); 566 break; 567 } 568 n0len = n0->m_pkthdr.len; /* save for use below */ 569 M_MOVE_PKTHDR(n, n0); 570 /* 571 * Copy IPv6 and ICMPv6 only. 572 */ 573 nip6 = mtod(n, struct ip6_hdr *); 574 bcopy(ip6, nip6, sizeof(struct ip6_hdr)); 575 nicmp6 = (struct icmp6_hdr *)(nip6 + 1); 576 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr)); 577 noff = sizeof(struct ip6_hdr); 578 /* new mbuf contains only ipv6+icmpv6 headers */ 579 n->m_len = noff + sizeof(struct icmp6_hdr); 580 /* 581 * Adjust mbuf. ip6_plen will be adjusted in 582 * ip6_output(). 583 */ 584 m_adj(n0, off + sizeof(struct icmp6_hdr)); 585 /* recalculate complete packet size */ 586 n->m_pkthdr.len = n0len + (noff - off); 587 n->m_next = n0; 588 } else { 589 nip6 = mtod(n, struct ip6_hdr *); 590 nicmp6 = (struct icmp6_hdr *)((caddr_t)nip6 + off); 591 noff = off; 592 } 593 nicmp6->icmp6_type = ICMP6_ECHO_REPLY; 594 nicmp6->icmp6_code = 0; 595 if (n) { 596 icmp6stat.icp6s_reflect++; 597 icmp6stat.icp6s_outhist[ICMP6_ECHO_REPLY]++; 598 icmp6_reflect(n, noff); 599 } 600 break; 601 602 case ICMP6_ECHO_REPLY: 603 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echoreply); 604 if (code != 0) 605 goto badcode; 606 break; 607 608 case MLD_LISTENER_QUERY: 609 case MLD_LISTENER_REPORT: 610 if (icmp6len < sizeof(struct mld_hdr)) 611 goto badlen; 612 if (icmp6->icmp6_type == MLD_LISTENER_QUERY) /* XXX: ugly... */ 613 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldquery); 614 else 615 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldreport); 616 if ((n = m_copym(m, 0, M_COPYALL, MB_DONTWAIT)) == NULL) { 617 /* give up local */ 618 mld6_input(m, off); 619 m = NULL; 620 goto freeit; 621 } 622 mld6_input(n, off); 623 /* m stays. */ 624 break; 625 626 case MLD_LISTENER_DONE: 627 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mlddone); 628 if (icmp6len < sizeof(struct mld_hdr)) /* necessary? */ 629 goto badlen; 630 break; /* nothing to be done in kernel */ 631 632 case MLD_MTRACE_RESP: 633 case MLD_MTRACE: 634 /* XXX: these two are experimental. not officially defind. */ 635 /* XXX: per-interface statistics? */ 636 break; /* just pass it to applications */ 637 638 case ICMP6_WRUREQUEST: /* ICMP6_FQDN_QUERY */ 639 { 640 enum { WRU, FQDN } mode; 641 642 if (!icmp6_nodeinfo) 643 break; 644 645 if (icmp6len == sizeof(struct icmp6_hdr) + 4) 646 mode = WRU; 647 else if (icmp6len >= sizeof(struct icmp6_nodeinfo)) 648 mode = FQDN; 649 else 650 goto badlen; 651 652 #define hostnamelen strlen(hostname) 653 if (mode == FQDN) { 654 #ifndef PULLDOWN_TEST 655 IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_nodeinfo), 656 IPPROTO_DONE); 657 #endif 658 n = m_copy(m, 0, M_COPYALL); 659 if (n) 660 n = ni6_input(n, off); 661 /* XXX meaningless if n == NULL */ 662 noff = sizeof(struct ip6_hdr); 663 } else { 664 u_char *p; 665 int maxlen, maxhlen; 666 667 if ((icmp6_nodeinfo & 5) != 5) 668 break; 669 670 if (code != 0) 671 goto badcode; 672 maxlen = sizeof(*nip6) + sizeof(*nicmp6) + 4; 673 if (maxlen >= MCLBYTES) { 674 /* Give up remote */ 675 break; 676 } 677 n = m_getb(maxlen, MB_DONTWAIT, m->m_type, M_PKTHDR); 678 if (n == NULL) { 679 /* Give up remote */ 680 break; 681 } 682 if (!m_dup_pkthdr(n, m, MB_DONTWAIT)) { 683 /* 684 * Previous code did a blind M_COPY_PKTHDR 685 * and said "just for rcvif". If true, then 686 * we could tolerate the dup failing (due to 687 * the deep copy of the tag chain). For now 688 * be conservative and just fail. 689 */ 690 m_free(n); 691 break; 692 } 693 n->m_len = 0; 694 maxhlen = M_TRAILINGSPACE(n) - maxlen; 695 if (maxhlen > hostnamelen) 696 maxhlen = hostnamelen; 697 /* 698 * Copy IPv6 and ICMPv6 only. 699 */ 700 nip6 = mtod(n, struct ip6_hdr *); 701 bcopy(ip6, nip6, sizeof(struct ip6_hdr)); 702 nicmp6 = (struct icmp6_hdr *)(nip6 + 1); 703 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr)); 704 p = (u_char *)(nicmp6 + 1); 705 bzero(p, 4); 706 bcopy(hostname, p + 4, maxhlen); /* meaningless TTL */ 707 noff = sizeof(struct ip6_hdr); 708 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) + 709 sizeof(struct icmp6_hdr) + 4 + maxhlen; 710 nicmp6->icmp6_type = ICMP6_WRUREPLY; 711 nicmp6->icmp6_code = 0; 712 } 713 #undef hostnamelen 714 if (n) { 715 icmp6stat.icp6s_reflect++; 716 icmp6stat.icp6s_outhist[ICMP6_WRUREPLY]++; 717 icmp6_reflect(n, noff); 718 } 719 break; 720 } 721 722 case ICMP6_WRUREPLY: 723 if (code != 0) 724 goto badcode; 725 break; 726 727 case ND_ROUTER_SOLICIT: 728 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routersolicit); 729 if (code != 0) 730 goto badcode; 731 if (icmp6len < sizeof(struct nd_router_solicit)) 732 goto badlen; 733 if ((n = m_copym(m, 0, M_COPYALL, MB_DONTWAIT)) == NULL) { 734 /* give up local */ 735 nd6_rs_input(m, off, icmp6len); 736 m = NULL; 737 goto freeit; 738 } 739 nd6_rs_input(n, off, icmp6len); 740 /* m stays. */ 741 break; 742 743 case ND_ROUTER_ADVERT: 744 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routeradvert); 745 if (code != 0) 746 goto badcode; 747 if (icmp6len < sizeof(struct nd_router_advert)) 748 goto badlen; 749 if ((n = m_copym(m, 0, M_COPYALL, MB_DONTWAIT)) == NULL) { 750 /* give up local */ 751 nd6_ra_input(m, off, icmp6len); 752 m = NULL; 753 goto freeit; 754 } 755 nd6_ra_input(n, off, icmp6len); 756 /* m stays. */ 757 break; 758 759 case ND_NEIGHBOR_SOLICIT: 760 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighborsolicit); 761 if (code != 0) 762 goto badcode; 763 if (icmp6len < sizeof(struct nd_neighbor_solicit)) 764 goto badlen; 765 if ((n = m_copym(m, 0, M_COPYALL, MB_DONTWAIT)) == NULL) { 766 /* give up local */ 767 nd6_ns_input(m, off, icmp6len); 768 m = NULL; 769 goto freeit; 770 } 771 nd6_ns_input(n, off, icmp6len); 772 /* m stays. */ 773 break; 774 775 case ND_NEIGHBOR_ADVERT: 776 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighboradvert); 777 if (code != 0) 778 goto badcode; 779 if (icmp6len < sizeof(struct nd_neighbor_advert)) 780 goto badlen; 781 if ((n = m_copym(m, 0, M_COPYALL, MB_DONTWAIT)) == NULL) { 782 /* give up local */ 783 nd6_na_input(m, off, icmp6len); 784 m = NULL; 785 goto freeit; 786 } 787 nd6_na_input(n, off, icmp6len); 788 /* m stays. */ 789 break; 790 791 case ND_REDIRECT: 792 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_redirect); 793 if (code != 0) 794 goto badcode; 795 if (icmp6len < sizeof(struct nd_redirect)) 796 goto badlen; 797 if ((n = m_copym(m, 0, M_COPYALL, MB_DONTWAIT)) == NULL) { 798 /* give up local */ 799 icmp6_redirect_input(m, off); 800 m = NULL; 801 goto freeit; 802 } 803 icmp6_redirect_input(n, off); 804 /* m stays. */ 805 break; 806 807 case ICMP6_ROUTER_RENUMBERING: 808 if (code != ICMP6_ROUTER_RENUMBERING_COMMAND && 809 code != ICMP6_ROUTER_RENUMBERING_RESULT) 810 goto badcode; 811 if (icmp6len < sizeof(struct icmp6_router_renum)) 812 goto badlen; 813 break; 814 815 default: 816 nd6log((LOG_DEBUG, 817 "icmp6_input: unknown type %d(src=%s, dst=%s, ifid=%d)\n", 818 icmp6->icmp6_type, ip6_sprintf(&ip6->ip6_src), 819 ip6_sprintf(&ip6->ip6_dst), 820 m->m_pkthdr.rcvif ? m->m_pkthdr.rcvif->if_index : 0)); 821 if (icmp6->icmp6_type < ICMP6_ECHO_REQUEST) { 822 /* ICMPv6 error: MUST deliver it by spec... */ 823 code = PRC_NCMDS; 824 /* deliver */ 825 } else { 826 /* ICMPv6 informational: MUST not deliver */ 827 break; 828 } 829 deliver: 830 if (icmp6_notify_error(m, off, icmp6len, code)) { 831 /* In this case, m should've been freed. */ 832 return (IPPROTO_DONE); 833 } 834 break; 835 836 badcode: 837 icmp6stat.icp6s_badcode++; 838 break; 839 840 badlen: 841 icmp6stat.icp6s_badlen++; 842 break; 843 } 844 845 /* deliver the packet to appropriate sockets */ 846 icmp6_rip6_input(&m, *offp); 847 848 return IPPROTO_DONE; 849 850 freeit: 851 m_freem(m); 852 return IPPROTO_DONE; 853 } 854 855 static int 856 icmp6_notify_error(struct mbuf *m, int off, int icmp6len, int code) 857 { 858 struct icmp6_hdr *icmp6; 859 struct ip6_hdr *eip6; 860 u_int32_t notifymtu; 861 struct sockaddr_in6 icmp6src, icmp6dst; 862 863 if (icmp6len < sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr)) { 864 icmp6stat.icp6s_tooshort++; 865 goto freeit; 866 } 867 #ifndef PULLDOWN_TEST 868 IP6_EXTHDR_CHECK(m, off, 869 sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr), 870 -1); 871 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 872 #else 873 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, 874 sizeof(*icmp6) + sizeof(struct ip6_hdr)); 875 if (icmp6 == NULL) { 876 icmp6stat.icp6s_tooshort++; 877 return (-1); 878 } 879 #endif 880 eip6 = (struct ip6_hdr *)(icmp6 + 1); 881 882 /* Detect the upper level protocol */ 883 { 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 int rthlen; 893 894 while (1) { /* XXX: should avoid infinite loop explicitly? */ 895 struct ip6_ext *eh; 896 897 switch (nxt) { 898 case IPPROTO_HOPOPTS: 899 case IPPROTO_DSTOPTS: 900 case IPPROTO_AH: 901 #ifndef PULLDOWN_TEST 902 IP6_EXTHDR_CHECK(m, 0, eoff + 903 sizeof(struct ip6_ext), 904 -1); 905 eh = (struct ip6_ext *)(mtod(m, caddr_t) 906 + eoff); 907 #else 908 IP6_EXTHDR_GET(eh, struct ip6_ext *, m, 909 eoff, sizeof(*eh)); 910 if (eh == NULL) { 911 icmp6stat.icp6s_tooshort++; 912 return (-1); 913 } 914 #endif 915 916 if (nxt == IPPROTO_AH) 917 eoff += (eh->ip6e_len + 2) << 2; 918 else 919 eoff += (eh->ip6e_len + 1) << 3; 920 nxt = eh->ip6e_nxt; 921 break; 922 case IPPROTO_ROUTING: 923 /* 924 * When the erroneous packet contains a 925 * routing header, we should examine the 926 * header to determine the final destination. 927 * Otherwise, we can't properly update 928 * information that depends on the final 929 * destination (e.g. path MTU). 930 */ 931 #ifndef PULLDOWN_TEST 932 IP6_EXTHDR_CHECK(m, 0, eoff + sizeof(*rth), 933 -1); 934 rth = (struct ip6_rthdr *)(mtod(m, caddr_t) 935 + eoff); 936 #else 937 IP6_EXTHDR_GET(rth, struct ip6_rthdr *, m, 938 eoff, sizeof(*rth)); 939 if (rth == NULL) { 940 icmp6stat.icp6s_tooshort++; 941 return (-1); 942 } 943 #endif 944 rthlen = (rth->ip6r_len + 1) << 3; 945 eoff += rthlen; 946 nxt = rth->ip6r_nxt; 947 break; 948 case IPPROTO_FRAGMENT: 949 #ifndef PULLDOWN_TEST 950 IP6_EXTHDR_CHECK(m, 0, eoff + 951 sizeof(struct ip6_frag), 952 -1); 953 fh = (struct ip6_frag *)(mtod(m, caddr_t) 954 + eoff); 955 #else 956 IP6_EXTHDR_GET(fh, struct ip6_frag *, m, 957 eoff, sizeof(*fh)); 958 if (fh == NULL) { 959 icmp6stat.icp6s_tooshort++; 960 return (-1); 961 } 962 #endif 963 /* 964 * Data after a fragment header is meaningless 965 * unless it is the first fragment, but 966 * we'll go to the notify label for path MTU 967 * discovery. 968 */ 969 if (fh->ip6f_offlg & IP6F_OFF_MASK) 970 goto notify; 971 972 eoff += sizeof(struct ip6_frag); 973 nxt = fh->ip6f_nxt; 974 break; 975 default: 976 /* 977 * This case includes ESP and the No Next 978 * Header. In such cases going to the notify 979 * label does not have any meaning 980 * (i.e. pr_ctlinput will be NULL), but we go 981 * anyway since we might have to update 982 * path MTU information. 983 */ 984 goto notify; 985 } 986 } 987 notify: 988 #ifndef PULLDOWN_TEST 989 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 990 #else 991 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, 992 sizeof(*icmp6) + sizeof(struct ip6_hdr)); 993 if (icmp6 == NULL) { 994 icmp6stat.icp6s_tooshort++; 995 return (-1); 996 } 997 #endif 998 999 eip6 = (struct ip6_hdr *)(icmp6 + 1); 1000 bzero(&icmp6dst, sizeof(icmp6dst)); 1001 icmp6dst.sin6_len = sizeof(struct sockaddr_in6); 1002 icmp6dst.sin6_family = AF_INET6; 1003 if (finaldst == NULL) 1004 icmp6dst.sin6_addr = eip6->ip6_dst; 1005 else 1006 icmp6dst.sin6_addr = *finaldst; 1007 icmp6dst.sin6_scope_id = in6_addr2scopeid(m->m_pkthdr.rcvif, 1008 &icmp6dst.sin6_addr); 1009 if (in6_embedscope(&icmp6dst.sin6_addr, &icmp6dst, 1010 NULL, NULL)) { 1011 /* should be impossbile */ 1012 nd6log((LOG_DEBUG, 1013 "icmp6_notify_error: in6_embedscope failed\n")); 1014 goto freeit; 1015 } 1016 1017 /* 1018 * retrieve parameters from the inner IPv6 header, and convert 1019 * them into sockaddr structures. 1020 */ 1021 bzero(&icmp6src, sizeof(icmp6src)); 1022 icmp6src.sin6_len = sizeof(struct sockaddr_in6); 1023 icmp6src.sin6_family = AF_INET6; 1024 icmp6src.sin6_addr = eip6->ip6_src; 1025 icmp6src.sin6_scope_id = in6_addr2scopeid(m->m_pkthdr.rcvif, 1026 &icmp6src.sin6_addr); 1027 if (in6_embedscope(&icmp6src.sin6_addr, &icmp6src, 1028 NULL, NULL)) { 1029 /* should be impossbile */ 1030 nd6log((LOG_DEBUG, 1031 "icmp6_notify_error: in6_embedscope failed\n")); 1032 goto freeit; 1033 } 1034 icmp6src.sin6_flowinfo = 1035 (eip6->ip6_flow & IPV6_FLOWLABEL_MASK); 1036 1037 if (finaldst == NULL) 1038 finaldst = &eip6->ip6_dst; 1039 ip6cp.ip6c_m = m; 1040 ip6cp.ip6c_icmp6 = icmp6; 1041 ip6cp.ip6c_ip6 = (struct ip6_hdr *)(icmp6 + 1); 1042 ip6cp.ip6c_off = eoff; 1043 ip6cp.ip6c_finaldst = finaldst; 1044 ip6cp.ip6c_src = &icmp6src; 1045 ip6cp.ip6c_nxt = nxt; 1046 1047 if (icmp6type == ICMP6_PACKET_TOO_BIG) { 1048 notifymtu = ntohl(icmp6->icmp6_mtu); 1049 ip6cp.ip6c_cmdarg = (void *)¬ifymtu; 1050 icmp6_mtudisc_update(&ip6cp, 1); /*XXX*/ 1051 } 1052 1053 so_pru_ctlinput( 1054 (struct protosw *)&inet6sw[ip6_protox[nxt]], 1055 code, (struct sockaddr *)&icmp6dst, &ip6cp); 1056 } 1057 return (0); 1058 1059 freeit: 1060 m_freem(m); 1061 return (-1); 1062 } 1063 1064 void 1065 icmp6_mtudisc_update(struct ip6ctlparam *ip6cp, int validated) 1066 { 1067 struct in6_addr *dst = ip6cp->ip6c_finaldst; 1068 struct icmp6_hdr *icmp6 = ip6cp->ip6c_icmp6; 1069 struct mbuf *m = ip6cp->ip6c_m; /* will be necessary for scope issue */ 1070 u_int mtu = ntohl(icmp6->icmp6_mtu); 1071 struct rtentry *rt = NULL; 1072 struct sockaddr_in6 sin6; 1073 1074 if (!validated) 1075 return; 1076 1077 bzero(&sin6, sizeof(sin6)); 1078 sin6.sin6_family = PF_INET6; 1079 sin6.sin6_len = sizeof(struct sockaddr_in6); 1080 sin6.sin6_addr = *dst; 1081 /* XXX normally, this won't happen */ 1082 if (IN6_IS_ADDR_LINKLOCAL(dst)) { 1083 sin6.sin6_addr.s6_addr16[1] = 1084 htons(m->m_pkthdr.rcvif->if_index); 1085 } 1086 /* sin6.sin6_scope_id = XXX: should be set if DST is a scoped addr */ 1087 rt = rtpurelookup((struct sockaddr *)&sin6); 1088 if (rt != NULL && (rt->rt_flags & RTF_HOST) && 1089 !(rt->rt_rmx.rmx_locks & RTV_MTU)) { 1090 if (mtu < IPV6_MMTU) { /* XXX */ 1091 rt->rt_rmx.rmx_locks |= RTV_MTU; 1092 } else if (mtu < rt->rt_ifp->if_mtu && 1093 rt->rt_rmx.rmx_mtu > mtu) { 1094 icmp6stat.icp6s_pmtuchg++; 1095 rt->rt_rmx.rmx_mtu = mtu; 1096 } 1097 } 1098 if (rt) 1099 --rt->rt_refcnt; 1100 } 1101 1102 /* 1103 * Process a Node Information Query packet, based on 1104 * draft-ietf-ipngwg-icmp-name-lookups-07. 1105 * 1106 * Spec incompatibilities: 1107 * - IPv6 Subject address handling 1108 * - IPv4 Subject address handling support missing 1109 * - Proxy reply (answer even if it's not for me) 1110 * - joins NI group address at in6_ifattach() time only, does not cope 1111 * with hostname changes by sethostname(3) 1112 */ 1113 #define hostnamelen strlen(hostname) 1114 static struct mbuf * 1115 ni6_input(struct mbuf *m, int off) 1116 { 1117 struct icmp6_nodeinfo *ni6, *nni6; 1118 struct mbuf *n = NULL; 1119 u_int16_t qtype; 1120 int subjlen; 1121 int replylen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo); 1122 struct ni_reply_fqdn *fqdn; 1123 int addrs; /* for NI_QTYPE_NODEADDR */ 1124 struct ifnet *ifp = NULL; /* for NI_QTYPE_NODEADDR */ 1125 struct sockaddr_in6 sin6; /* double meaning; ip6_dst and subjectaddr */ 1126 struct sockaddr_in6 sin6_d; /* XXX: we should retrieve this from m_aux */ 1127 struct ip6_hdr *ip6; 1128 int oldfqdn = 0; /* if 1, return pascal string (03 draft) */ 1129 char *subj = NULL; 1130 struct in6_ifaddr *ia6 = NULL; 1131 1132 ip6 = mtod(m, struct ip6_hdr *); 1133 #ifndef PULLDOWN_TEST 1134 ni6 = (struct icmp6_nodeinfo *)(mtod(m, caddr_t) + off); 1135 #else 1136 IP6_EXTHDR_GET(ni6, struct icmp6_nodeinfo *, m, off, sizeof(*ni6)); 1137 if (ni6 == NULL) { 1138 /* m is already reclaimed */ 1139 return NULL; 1140 } 1141 #endif 1142 1143 /* 1144 * Validate IPv6 destination address. 1145 * 1146 * The Responder must discard the Query without further processing 1147 * unless it is one of the Responder's unicast or anycast addresses, or 1148 * a link-local scope multicast address which the Responder has joined. 1149 * [icmp-name-lookups-07, Section 4.] 1150 */ 1151 bzero(&sin6, sizeof(sin6)); 1152 sin6.sin6_family = AF_INET6; 1153 sin6.sin6_len = sizeof(struct sockaddr_in6); 1154 bcopy(&ip6->ip6_dst, &sin6.sin6_addr, sizeof(sin6.sin6_addr)); 1155 /* XXX scopeid */ 1156 if ((ia6 = (struct in6_ifaddr *)ifa_ifwithaddr((struct sockaddr *)&sin6)) != NULL) { 1157 /* unicast/anycast, fine */ 1158 if ((ia6->ia6_flags & IN6_IFF_TEMPORARY) && 1159 (icmp6_nodeinfo & 4) == 0) { 1160 nd6log((LOG_DEBUG, "ni6_input: ignore node info to " 1161 "a temporary address in %s:%d", 1162 __FILE__, __LINE__)); 1163 goto bad; 1164 } 1165 } else if (IN6_IS_ADDR_MC_LINKLOCAL(&sin6.sin6_addr)) 1166 ; /* link-local multicast, fine */ 1167 else 1168 goto bad; 1169 1170 /* validate query Subject field. */ 1171 qtype = ntohs(ni6->ni_qtype); 1172 subjlen = m->m_pkthdr.len - off - sizeof(struct icmp6_nodeinfo); 1173 switch (qtype) { 1174 case NI_QTYPE_NOOP: 1175 case NI_QTYPE_SUPTYPES: 1176 /* 07 draft */ 1177 if (ni6->ni_code == ICMP6_NI_SUBJ_FQDN && subjlen == 0) 1178 break; 1179 /* FALLTHROUGH */ 1180 case NI_QTYPE_FQDN: 1181 case NI_QTYPE_NODEADDR: 1182 switch (ni6->ni_code) { 1183 case ICMP6_NI_SUBJ_IPV6: 1184 #if ICMP6_NI_SUBJ_IPV6 != 0 1185 case 0: 1186 #endif 1187 /* 1188 * backward compatibility - try to accept 03 draft 1189 * format, where no Subject is present. 1190 */ 1191 if (qtype == NI_QTYPE_FQDN && ni6->ni_code == 0 && 1192 subjlen == 0) { 1193 oldfqdn++; 1194 break; 1195 } 1196 #if ICMP6_NI_SUBJ_IPV6 != 0 1197 if (ni6->ni_code != ICMP6_NI_SUBJ_IPV6) 1198 goto bad; 1199 #endif 1200 1201 if (subjlen != sizeof(sin6.sin6_addr)) 1202 goto bad; 1203 1204 /* 1205 * Validate Subject address. 1206 * 1207 * Not sure what exactly "address belongs to the node" 1208 * means in the spec, is it just unicast, or what? 1209 * 1210 * At this moment we consider Subject address as 1211 * "belong to the node" if the Subject address equals 1212 * to the IPv6 destination address; validation for 1213 * IPv6 destination address should have done enough 1214 * check for us. 1215 * 1216 * We do not do proxy at this moment. 1217 */ 1218 /* m_pulldown instead of copy? */ 1219 m_copydata(m, off + sizeof(struct icmp6_nodeinfo), 1220 subjlen, (caddr_t)&sin6.sin6_addr); 1221 sin6.sin6_scope_id = in6_addr2scopeid(m->m_pkthdr.rcvif, 1222 &sin6.sin6_addr); 1223 in6_embedscope(&sin6.sin6_addr, &sin6, NULL, NULL); 1224 bzero(&sin6_d, sizeof(sin6_d)); 1225 sin6_d.sin6_family = AF_INET6; /* not used, actually */ 1226 sin6_d.sin6_len = sizeof(sin6_d); /* ditto */ 1227 sin6_d.sin6_addr = ip6->ip6_dst; 1228 sin6_d.sin6_scope_id = in6_addr2scopeid(m->m_pkthdr.rcvif, 1229 &ip6->ip6_dst); 1230 in6_embedscope(&sin6_d.sin6_addr, &sin6_d, NULL, NULL); 1231 subj = (char *)&sin6; 1232 if (SA6_ARE_ADDR_EQUAL(&sin6, &sin6_d)) 1233 break; 1234 1235 /* 1236 * XXX if we are to allow other cases, we should really 1237 * be careful about scope here. 1238 * basically, we should disallow queries toward IPv6 1239 * destination X with subject Y, if scope(X) > scope(Y). 1240 * if we allow scope(X) > scope(Y), it will result in 1241 * information leakage across scope boundary. 1242 */ 1243 goto bad; 1244 1245 case ICMP6_NI_SUBJ_FQDN: 1246 /* 1247 * Validate Subject name with gethostname(3). 1248 * 1249 * The behavior may need some debate, since: 1250 * - we are not sure if the node has FQDN as 1251 * hostname (returned by gethostname(3)). 1252 * - the code does wildcard match for truncated names. 1253 * however, we are not sure if we want to perform 1254 * wildcard match, if gethostname(3) side has 1255 * truncated hostname. 1256 */ 1257 n = ni6_nametodns(hostname, hostnamelen, 0); 1258 if (!n || n->m_next || n->m_len == 0) 1259 goto bad; 1260 IP6_EXTHDR_GET(subj, char *, m, 1261 off + sizeof(struct icmp6_nodeinfo), subjlen); 1262 if (subj == NULL) 1263 goto bad; 1264 if (!ni6_dnsmatch(subj, subjlen, mtod(n, const char *), 1265 n->m_len)) { 1266 goto bad; 1267 } 1268 m_freem(n); 1269 n = NULL; 1270 break; 1271 1272 case ICMP6_NI_SUBJ_IPV4: /* XXX: to be implemented? */ 1273 default: 1274 goto bad; 1275 } 1276 break; 1277 } 1278 1279 /* refuse based on configuration. XXX ICMP6_NI_REFUSED? */ 1280 switch (qtype) { 1281 case NI_QTYPE_FQDN: 1282 if ((icmp6_nodeinfo & 1) == 0) 1283 goto bad; 1284 break; 1285 case NI_QTYPE_NODEADDR: 1286 if ((icmp6_nodeinfo & 2) == 0) 1287 goto bad; 1288 break; 1289 } 1290 1291 /* guess reply length */ 1292 switch (qtype) { 1293 case NI_QTYPE_NOOP: 1294 break; /* no reply data */ 1295 case NI_QTYPE_SUPTYPES: 1296 replylen += sizeof(u_int32_t); 1297 break; 1298 case NI_QTYPE_FQDN: 1299 /* XXX will append an mbuf */ 1300 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1301 break; 1302 case NI_QTYPE_NODEADDR: 1303 addrs = ni6_addrs(ni6, m, &ifp, subj); 1304 if ((replylen += addrs * (sizeof(struct in6_addr) + 1305 sizeof(u_int32_t))) > MCLBYTES) 1306 replylen = MCLBYTES; /* XXX: will truncate pkt later */ 1307 break; 1308 default: 1309 /* 1310 * XXX: We must return a reply with the ICMP6 code 1311 * `unknown Qtype' in this case. However we regard the case 1312 * as an FQDN query for backward compatibility. 1313 * Older versions set a random value to this field, 1314 * so it rarely varies in the defined qtypes. 1315 * But the mechanism is not reliable... 1316 * maybe we should obsolete older versions. 1317 */ 1318 qtype = NI_QTYPE_FQDN; 1319 /* XXX will append an mbuf */ 1320 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1321 oldfqdn++; 1322 break; 1323 } 1324 1325 /* allocate an mbuf to reply. */ 1326 if (replylen > MCLBYTES) { 1327 /* 1328 * XXX: should we try to allocate more? But MCLBYTES 1329 * is probably much larger than IPV6_MMTU... 1330 */ 1331 goto bad; 1332 } 1333 n = m_getb(replylen, MB_DONTWAIT, m->m_type, M_PKTHDR); 1334 if (n == NULL) { 1335 m_freem(m); 1336 return (NULL); 1337 } 1338 M_MOVE_PKTHDR(n, m); /* just for recvif */ 1339 n->m_pkthdr.len = n->m_len = replylen; 1340 1341 /* copy mbuf header and IPv6 + Node Information base headers */ 1342 bcopy(mtod(m, caddr_t), mtod(n, caddr_t), sizeof(struct ip6_hdr)); 1343 nni6 = (struct icmp6_nodeinfo *)(mtod(n, struct ip6_hdr *) + 1); 1344 bcopy((caddr_t)ni6, (caddr_t)nni6, sizeof(struct icmp6_nodeinfo)); 1345 1346 /* qtype dependent procedure */ 1347 switch (qtype) { 1348 case NI_QTYPE_NOOP: 1349 nni6->ni_code = ICMP6_NI_SUCCESS; 1350 nni6->ni_flags = 0; 1351 break; 1352 case NI_QTYPE_SUPTYPES: 1353 { 1354 u_int32_t v; 1355 nni6->ni_code = ICMP6_NI_SUCCESS; 1356 nni6->ni_flags = htons(0x0000); /* raw bitmap */ 1357 /* supports NOOP, SUPTYPES, FQDN, and NODEADDR */ 1358 v = (u_int32_t)htonl(0x0000000f); 1359 bcopy(&v, nni6 + 1, sizeof(u_int32_t)); 1360 break; 1361 } 1362 case NI_QTYPE_FQDN: 1363 nni6->ni_code = ICMP6_NI_SUCCESS; 1364 fqdn = (struct ni_reply_fqdn *)(mtod(n, caddr_t) + 1365 sizeof(struct ip6_hdr) + 1366 sizeof(struct icmp6_nodeinfo)); 1367 nni6->ni_flags = 0; /* XXX: meaningless TTL */ 1368 fqdn->ni_fqdn_ttl = 0; /* ditto. */ 1369 /* 1370 * XXX do we really have FQDN in variable "hostname"? 1371 */ 1372 n->m_next = ni6_nametodns(hostname, hostnamelen, oldfqdn); 1373 if (n->m_next == NULL) 1374 goto bad; 1375 /* XXX we assume that n->m_next is not a chain */ 1376 if (n->m_next->m_next != NULL) 1377 goto bad; 1378 n->m_pkthdr.len += n->m_next->m_len; 1379 break; 1380 case NI_QTYPE_NODEADDR: 1381 { 1382 int lenlim, copied; 1383 1384 nni6->ni_code = ICMP6_NI_SUCCESS; 1385 n->m_pkthdr.len = n->m_len = 1386 sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo); 1387 lenlim = M_TRAILINGSPACE(n); 1388 copied = ni6_store_addrs(ni6, nni6, ifp, lenlim); 1389 /* XXX: reset mbuf length */ 1390 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) + 1391 sizeof(struct icmp6_nodeinfo) + copied; 1392 break; 1393 } 1394 default: 1395 break; /* XXX impossible! */ 1396 } 1397 1398 nni6->ni_type = ICMP6_NI_REPLY; 1399 m_freem(m); 1400 return (n); 1401 1402 bad: 1403 m_freem(m); 1404 if (n) 1405 m_freem(n); 1406 return (NULL); 1407 } 1408 #undef hostnamelen 1409 1410 /* 1411 * make a mbuf with DNS-encoded string. no compression support. 1412 * 1413 * XXX names with less than 2 dots (like "foo" or "foo.section") will be 1414 * treated as truncated name (two \0 at the end). this is a wild guess. 1415 */ 1416 static struct mbuf * 1417 ni6_nametodns(const char *name, int namelen, 1418 int old) /* return pascal string if non-zero */ 1419 { 1420 struct mbuf *m; 1421 char *cp, *ep; 1422 const char *p, *q; 1423 int i, len, nterm; 1424 1425 if (old) 1426 len = namelen + 1; 1427 else 1428 len = MCLBYTES; 1429 1430 /* because MAXHOSTNAMELEN is usually 256, we use cluster mbuf */ 1431 m = m_getb(len, MB_DONTWAIT, MT_DATA, 0); 1432 if (!m) 1433 goto fail; 1434 1435 if (old) { 1436 m->m_len = len; 1437 *mtod(m, char *) = namelen; 1438 bcopy(name, mtod(m, char *) + 1, namelen); 1439 return m; 1440 } else { 1441 m->m_len = 0; 1442 cp = mtod(m, char *); 1443 ep = mtod(m, char *) + M_TRAILINGSPACE(m); 1444 1445 /* if not certain about my name, return empty buffer */ 1446 if (namelen == 0) 1447 return m; 1448 1449 /* 1450 * guess if it looks like shortened hostname, or FQDN. 1451 * shortened hostname needs two trailing "\0". 1452 */ 1453 i = 0; 1454 for (p = name; p < name + namelen; p++) { 1455 if (*p && *p == '.') 1456 i++; 1457 } 1458 if (i < 2) 1459 nterm = 2; 1460 else 1461 nterm = 1; 1462 1463 p = name; 1464 while (cp < ep && p < name + namelen) { 1465 i = 0; 1466 for (q = p; q < name + namelen && *q && *q != '.'; q++) 1467 i++; 1468 /* result does not fit into mbuf */ 1469 if (cp + i + 1 >= ep) 1470 goto fail; 1471 /* 1472 * DNS label length restriction, RFC1035 page 8. 1473 * "i == 0" case is included here to avoid returning 1474 * 0-length label on "foo..bar". 1475 */ 1476 if (i <= 0 || i >= 64) 1477 goto fail; 1478 *cp++ = i; 1479 bcopy(p, cp, i); 1480 cp += i; 1481 p = q; 1482 if (p < name + namelen && *p == '.') 1483 p++; 1484 } 1485 /* termination */ 1486 if (cp + nterm >= ep) 1487 goto fail; 1488 while (nterm-- > 0) 1489 *cp++ = '\0'; 1490 m->m_len = cp - mtod(m, char *); 1491 return m; 1492 } 1493 1494 panic("should not reach here"); 1495 /* NOTREACHED */ 1496 1497 fail: 1498 if (m) 1499 m_freem(m); 1500 return NULL; 1501 } 1502 1503 /* 1504 * check if two DNS-encoded string matches. takes care of truncated 1505 * form (with \0\0 at the end). no compression support. 1506 * XXX upper/lowercase match (see RFC2065) 1507 */ 1508 static int 1509 ni6_dnsmatch(const char *a, int alen, const char *b, int blen) 1510 { 1511 const char *a0, *b0; 1512 int l; 1513 1514 /* simplest case - need validation? */ 1515 if (alen == blen && bcmp(a, b, alen) == 0) 1516 return 1; 1517 1518 a0 = a; 1519 b0 = b; 1520 1521 /* termination is mandatory */ 1522 if (alen < 2 || blen < 2) 1523 return 0; 1524 if (a0[alen - 1] != '\0' || b0[blen - 1] != '\0') 1525 return 0; 1526 alen--; 1527 blen--; 1528 1529 while (a - a0 < alen && b - b0 < blen) { 1530 if (a - a0 + 1 > alen || b - b0 + 1 > blen) 1531 return 0; 1532 1533 if ((signed char)a[0] < 0 || (signed char)b[0] < 0) 1534 return 0; 1535 /* we don't support compression yet */ 1536 if (a[0] >= 64 || b[0] >= 64) 1537 return 0; 1538 1539 /* truncated case */ 1540 if (a[0] == 0 && a - a0 == alen - 1) 1541 return 1; 1542 if (b[0] == 0 && b - b0 == blen - 1) 1543 return 1; 1544 if (a[0] == 0 || b[0] == 0) 1545 return 0; 1546 1547 if (a[0] != b[0]) 1548 return 0; 1549 l = a[0]; 1550 if (a - a0 + 1 + l > alen || b - b0 + 1 + l > blen) 1551 return 0; 1552 if (bcmp(a + 1, b + 1, l) != 0) 1553 return 0; 1554 1555 a += 1 + l; 1556 b += 1 + l; 1557 } 1558 1559 if (a - a0 == alen && b - b0 == blen) 1560 return 1; 1561 else 1562 return 0; 1563 } 1564 1565 /* 1566 * calculate the number of addresses to be returned in the node info reply. 1567 */ 1568 static int 1569 ni6_addrs(struct icmp6_nodeinfo *ni6, struct mbuf *m, struct ifnet **ifpp, 1570 char *subj) 1571 { 1572 struct ifnet *ifp; 1573 struct in6_ifaddr *ifa6; 1574 struct sockaddr_in6 *subj_ip6 = NULL; /* XXX pedant */ 1575 int addrs = 0, addrsofif, iffound = 0; 1576 int niflags = ni6->ni_flags; 1577 1578 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0) { 1579 switch (ni6->ni_code) { 1580 case ICMP6_NI_SUBJ_IPV6: 1581 if (subj == NULL) /* must be impossible... */ 1582 return (0); 1583 subj_ip6 = (struct sockaddr_in6 *)subj; 1584 break; 1585 default: 1586 /* 1587 * XXX: we only support IPv6 subject address for 1588 * this Qtype. 1589 */ 1590 return (0); 1591 } 1592 } 1593 1594 for (ifp = TAILQ_FIRST(&ifnet); ifp; ifp = TAILQ_NEXT(ifp, if_list)) 1595 { 1596 struct ifaddr_container *ifac; 1597 1598 addrsofif = 0; 1599 TAILQ_FOREACH(ifac, &ifp->if_addrheads[mycpuid], ifa_link) 1600 { 1601 struct ifaddr *ifa = ifac->ifa; 1602 1603 if (ifa->ifa_addr->sa_family != AF_INET6) 1604 continue; 1605 ifa6 = (struct in6_ifaddr *)ifa; 1606 1607 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0 && 1608 IN6_ARE_ADDR_EQUAL(&subj_ip6->sin6_addr, 1609 &ifa6->ia_addr.sin6_addr)) 1610 iffound = 1; 1611 1612 /* 1613 * IPv4-mapped addresses can only be returned by a 1614 * Node Information proxy, since they represent 1615 * addresses of IPv4-only nodes, which perforce do 1616 * not implement this protocol. 1617 * [icmp-name-lookups-07, Section 5.4] 1618 * So we don't support NI_NODEADDR_FLAG_COMPAT in 1619 * this function at this moment. 1620 */ 1621 1622 /* What do we have to do about ::1? */ 1623 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1624 case IPV6_ADDR_SCOPE_LINKLOCAL: 1625 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0) 1626 continue; 1627 break; 1628 case IPV6_ADDR_SCOPE_SITELOCAL: 1629 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0) 1630 continue; 1631 break; 1632 case IPV6_ADDR_SCOPE_GLOBAL: 1633 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0) 1634 continue; 1635 break; 1636 default: 1637 continue; 1638 } 1639 1640 /* 1641 * check if anycast is okay. 1642 * XXX: just experimental. not in the spec. 1643 */ 1644 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) && 1645 !(niflags & NI_NODEADDR_FLAG_ANYCAST)) 1646 continue; /* we need only unicast addresses */ 1647 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) && 1648 (icmp6_nodeinfo & 4) == 0) { 1649 continue; 1650 } 1651 addrsofif++; /* count the address */ 1652 } 1653 if (iffound) { 1654 *ifpp = ifp; 1655 return (addrsofif); 1656 } 1657 1658 addrs += addrsofif; 1659 } 1660 1661 return (addrs); 1662 } 1663 1664 static int 1665 ni6_store_addrs(struct icmp6_nodeinfo *ni6, struct icmp6_nodeinfo *nni6, 1666 struct ifnet *ifp0, int resid) 1667 { 1668 struct ifnet *ifp = ifp0 ? ifp0 : TAILQ_FIRST(&ifnet); 1669 struct in6_ifaddr *ifa6; 1670 struct ifnet *ifp_dep = NULL; 1671 int copied = 0, allow_deprecated = 0; 1672 u_char *cp = (u_char *)(nni6 + 1); 1673 int niflags = ni6->ni_flags; 1674 u_int32_t ltime; 1675 1676 if (ifp0 == NULL && !(niflags & NI_NODEADDR_FLAG_ALL)) 1677 return (0); /* needless to copy */ 1678 1679 again: 1680 1681 for (; ifp; ifp = TAILQ_NEXT(ifp, if_list)) 1682 { 1683 struct ifaddr_container *ifac; 1684 1685 TAILQ_FOREACH(ifac, &ifp->if_addrheads[mycpuid], ifa_link) { 1686 struct ifaddr *ifa = ifac->ifa; 1687 1688 if (ifa->ifa_addr->sa_family != AF_INET6) 1689 continue; 1690 ifa6 = (struct in6_ifaddr *)ifa; 1691 1692 if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) && 1693 allow_deprecated == 0) { 1694 /* 1695 * prefererred address should be put before 1696 * deprecated addresses. 1697 */ 1698 1699 /* record the interface for later search */ 1700 if (ifp_dep == NULL) 1701 ifp_dep = ifp; 1702 1703 continue; 1704 } 1705 else if (!(ifa6->ia6_flags & IN6_IFF_DEPRECATED) && 1706 allow_deprecated != 0) 1707 continue; /* we now collect deprecated addrs */ 1708 1709 /* What do we have to do about ::1? */ 1710 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1711 case IPV6_ADDR_SCOPE_LINKLOCAL: 1712 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0) 1713 continue; 1714 break; 1715 case IPV6_ADDR_SCOPE_SITELOCAL: 1716 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0) 1717 continue; 1718 break; 1719 case IPV6_ADDR_SCOPE_GLOBAL: 1720 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0) 1721 continue; 1722 break; 1723 default: 1724 continue; 1725 } 1726 1727 /* 1728 * check if anycast is okay. 1729 * XXX: just experimental. not in the spec. 1730 */ 1731 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) && 1732 !(niflags & NI_NODEADDR_FLAG_ANYCAST)) 1733 continue; 1734 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) && 1735 (icmp6_nodeinfo & 4) == 0) { 1736 continue; 1737 } 1738 1739 /* now we can copy the address */ 1740 if (resid < sizeof(struct in6_addr) + 1741 sizeof(u_int32_t)) { 1742 /* 1743 * We give up much more copy. 1744 * Set the truncate flag and return. 1745 */ 1746 nni6->ni_flags |= 1747 NI_NODEADDR_FLAG_TRUNCATE; 1748 return (copied); 1749 } 1750 1751 /* 1752 * Set the TTL of the address. 1753 * The TTL value should be one of the following 1754 * according to the specification: 1755 * 1756 * 1. The remaining lifetime of a DHCP lease on the 1757 * address, or 1758 * 2. The remaining Valid Lifetime of a prefix from 1759 * which the address was derived through Stateless 1760 * Autoconfiguration. 1761 * 1762 * Note that we currently do not support stateful 1763 * address configuration by DHCPv6, so the former 1764 * case can't happen. 1765 */ 1766 if (ifa6->ia6_lifetime.ia6t_expire == 0) 1767 ltime = ND6_INFINITE_LIFETIME; 1768 else { 1769 if (ifa6->ia6_lifetime.ia6t_expire > 1770 time_second) 1771 ltime = htonl(ifa6->ia6_lifetime.ia6t_expire - time_second); 1772 else 1773 ltime = 0; 1774 } 1775 1776 bcopy(<ime, cp, sizeof(u_int32_t)); 1777 cp += sizeof(u_int32_t); 1778 1779 /* copy the address itself */ 1780 bcopy(&ifa6->ia_addr.sin6_addr, cp, 1781 sizeof(struct in6_addr)); 1782 /* XXX: KAME link-local hack; remove ifindex */ 1783 if (IN6_IS_ADDR_LINKLOCAL(&ifa6->ia_addr.sin6_addr)) 1784 ((struct in6_addr *)cp)->s6_addr16[1] = 0; 1785 cp += sizeof(struct in6_addr); 1786 1787 resid -= (sizeof(struct in6_addr) + sizeof(u_int32_t)); 1788 copied += (sizeof(struct in6_addr) + 1789 sizeof(u_int32_t)); 1790 } 1791 if (ifp0) /* we need search only on the specified IF */ 1792 break; 1793 } 1794 1795 if (allow_deprecated == 0 && ifp_dep != NULL) { 1796 ifp = ifp_dep; 1797 allow_deprecated = 1; 1798 1799 goto again; 1800 } 1801 1802 return (copied); 1803 } 1804 1805 /* 1806 * XXX almost dup'ed code with rip6_input. 1807 */ 1808 static int 1809 icmp6_rip6_input(struct mbuf **mp, int off) 1810 { 1811 struct mbuf *m = *mp; 1812 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1813 struct in6pcb *in6p; 1814 struct in6pcb *last = NULL; 1815 struct sockaddr_in6 rip6src; 1816 struct icmp6_hdr *icmp6; 1817 struct mbuf *opts = NULL; 1818 1819 #ifndef PULLDOWN_TEST 1820 /* this is assumed to be safe. */ 1821 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off); 1822 #else 1823 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 1824 if (icmp6 == NULL) { 1825 /* m is already reclaimed */ 1826 return IPPROTO_DONE; 1827 } 1828 #endif 1829 1830 bzero(&rip6src, sizeof(rip6src)); 1831 rip6src.sin6_len = sizeof(struct sockaddr_in6); 1832 rip6src.sin6_family = AF_INET6; 1833 /* KAME hack: recover scopeid */ 1834 in6_recoverscope(&rip6src, &ip6->ip6_src, m->m_pkthdr.rcvif); 1835 1836 LIST_FOREACH(in6p, &ripcbinfo.pcblisthead, inp_list) 1837 { 1838 if (in6p->inp_flags & INP_PLACEMARKER) 1839 continue; 1840 if ((in6p->inp_vflag & INP_IPV6) == 0) 1841 continue; 1842 #ifdef HAVE_NRL_INPCB 1843 if (!(in6p->in6p_flags & INP_IPV6)) 1844 continue; 1845 #endif 1846 if (in6p->in6p_ip6_nxt != IPPROTO_ICMPV6) 1847 continue; 1848 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr) && 1849 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr, &ip6->ip6_dst)) 1850 continue; 1851 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr) && 1852 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr, &ip6->ip6_src)) 1853 continue; 1854 if (in6p->in6p_icmp6filt 1855 && ICMP6_FILTER_WILLBLOCK(icmp6->icmp6_type, 1856 in6p->in6p_icmp6filt)) 1857 continue; 1858 if (last) { 1859 struct mbuf *n; 1860 if ((n = m_copy(m, 0, (int)M_COPYALL)) != NULL) { 1861 if (last->in6p_flags & IN6P_CONTROLOPTS) 1862 ip6_savecontrol(last, &opts, ip6, n); 1863 /* strip intermediate headers */ 1864 m_adj(n, off); 1865 if (ssb_appendaddr(&last->in6p_socket->so_rcv, 1866 (struct sockaddr *)&rip6src, 1867 n, opts) == 0) { 1868 /* should notify about lost packet */ 1869 m_freem(n); 1870 if (opts) { 1871 m_freem(opts); 1872 } 1873 } else 1874 sorwakeup(last->in6p_socket); 1875 opts = NULL; 1876 } 1877 } 1878 last = in6p; 1879 } 1880 if (last) { 1881 if (last->in6p_flags & IN6P_CONTROLOPTS) 1882 ip6_savecontrol(last, &opts, ip6, m); 1883 /* strip intermediate headers */ 1884 m_adj(m, off); 1885 if (ssb_appendaddr(&last->in6p_socket->so_rcv, 1886 (struct sockaddr *)&rip6src, m, opts) == 0) { 1887 m_freem(m); 1888 if (opts) 1889 m_freem(opts); 1890 } else 1891 sorwakeup(last->in6p_socket); 1892 } else { 1893 m_freem(m); 1894 ip6stat.ip6s_delivered--; 1895 } 1896 return IPPROTO_DONE; 1897 } 1898 1899 /* 1900 * Reflect the ip6 packet back to the source. 1901 * OFF points to the icmp6 header, counted from the top of the mbuf. 1902 */ 1903 void 1904 icmp6_reflect(struct mbuf *m, size_t off) 1905 { 1906 struct ip6_hdr *ip6; 1907 struct icmp6_hdr *icmp6; 1908 struct in6_ifaddr *ia; 1909 struct in6_addr t, *src = 0; 1910 int plen; 1911 int type, code; 1912 struct ifnet *outif = NULL; 1913 struct sockaddr_in6 sa6_src, sa6_dst; 1914 #ifdef COMPAT_RFC1885 1915 int mtu = IPV6_MMTU; 1916 struct sockaddr_in6 *sin6 = &icmp6_reflect_rt.ro_dst; 1917 #endif 1918 1919 /* too short to reflect */ 1920 if (off < sizeof(struct ip6_hdr)) { 1921 nd6log((LOG_DEBUG, 1922 "sanity fail: off=%lx, sizeof(ip6)=%lx in %s:%d\n", 1923 (u_long)off, (u_long)sizeof(struct ip6_hdr), 1924 __FILE__, __LINE__)); 1925 goto bad; 1926 } 1927 1928 /* 1929 * If there are extra headers between IPv6 and ICMPv6, strip 1930 * off that header first. 1931 */ 1932 #ifdef DIAGNOSTIC 1933 if (sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) > MHLEN) 1934 panic("assumption failed in icmp6_reflect"); 1935 #endif 1936 if (off > sizeof(struct ip6_hdr)) { 1937 size_t l; 1938 struct ip6_hdr nip6; 1939 1940 l = off - sizeof(struct ip6_hdr); 1941 m_copydata(m, 0, sizeof(nip6), (caddr_t)&nip6); 1942 m_adj(m, l); 1943 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 1944 if (m->m_len < l) { 1945 if ((m = m_pullup(m, l)) == NULL) 1946 return; 1947 } 1948 bcopy((caddr_t)&nip6, mtod(m, caddr_t), sizeof(nip6)); 1949 } else /* off == sizeof(struct ip6_hdr) */ { 1950 size_t l; 1951 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 1952 if (m->m_len < l) { 1953 if ((m = m_pullup(m, l)) == NULL) 1954 return; 1955 } 1956 } 1957 plen = m->m_pkthdr.len - sizeof(struct ip6_hdr); 1958 ip6 = mtod(m, struct ip6_hdr *); 1959 ip6->ip6_nxt = IPPROTO_ICMPV6; 1960 icmp6 = (struct icmp6_hdr *)(ip6 + 1); 1961 type = icmp6->icmp6_type; /* keep type for statistics */ 1962 code = icmp6->icmp6_code; /* ditto. */ 1963 1964 t = ip6->ip6_dst; 1965 /* 1966 * ip6_input() drops a packet if its src is multicast. 1967 * So, the src is never multicast. 1968 */ 1969 ip6->ip6_dst = ip6->ip6_src; 1970 1971 /* 1972 * XXX: make sure to embed scope zone information, using 1973 * already embedded IDs or the received interface (if any). 1974 * Note that rcvif may be NULL. 1975 * TODO: scoped routing case (XXX). 1976 */ 1977 bzero(&sa6_src, sizeof(sa6_src)); 1978 sa6_src.sin6_family = AF_INET6; 1979 sa6_src.sin6_len = sizeof(sa6_src); 1980 sa6_src.sin6_addr = ip6->ip6_dst; 1981 in6_recoverscope(&sa6_src, &ip6->ip6_dst, m->m_pkthdr.rcvif); 1982 in6_embedscope(&ip6->ip6_dst, &sa6_src, NULL, NULL); 1983 bzero(&sa6_dst, sizeof(sa6_dst)); 1984 sa6_dst.sin6_family = AF_INET6; 1985 sa6_dst.sin6_len = sizeof(sa6_dst); 1986 sa6_dst.sin6_addr = t; 1987 in6_recoverscope(&sa6_dst, &t, m->m_pkthdr.rcvif); 1988 in6_embedscope(&t, &sa6_dst, NULL, NULL); 1989 1990 #ifdef COMPAT_RFC1885 1991 /* 1992 * xxx guess MTU 1993 * RFC 1885 requires that echo reply should be truncated if it 1994 * does not fit in with (return) path MTU, but the description was 1995 * removed in the new spec. 1996 */ 1997 if (icmp6_reflect_rt.ro_rt == 0 || 1998 ! (IN6_ARE_ADDR_EQUAL(&sin6->sin6_addr, &ip6->ip6_dst))) { 1999 if (icmp6_reflect_rt.ro_rt) { 2000 RTFREE(icmp6_reflect_rt.ro_rt); 2001 icmp6_reflect_rt.ro_rt = 0; 2002 } 2003 bzero(sin6, sizeof(*sin6)); 2004 sin6->sin6_family = PF_INET6; 2005 sin6->sin6_len = sizeof(struct sockaddr_in6); 2006 sin6->sin6_addr = ip6->ip6_dst; 2007 2008 rtalloc_ign((struct route *)&icmp6_reflect_rt.ro_rt, 2009 RTF_PRCLONING); 2010 } 2011 2012 if (icmp6_reflect_rt.ro_rt == 0) 2013 goto bad; 2014 2015 if ((icmp6_reflect_rt.ro_rt->rt_flags & RTF_HOST) 2016 && mtu < icmp6_reflect_rt.ro_rt->rt_ifp->if_mtu) 2017 mtu = icmp6_reflect_rt.ro_rt->rt_rmx.rmx_mtu; 2018 2019 if (mtu < m->m_pkthdr.len) { 2020 plen -= (m->m_pkthdr.len - mtu); 2021 m_adj(m, mtu - m->m_pkthdr.len); 2022 } 2023 #endif 2024 /* 2025 * If the incoming packet was addressed directly to us(i.e. unicast), 2026 * use dst as the src for the reply. 2027 * The IN6_IFF_NOTREADY case would be VERY rare, but is possible 2028 * (for example) when we encounter an error while forwarding procedure 2029 * destined to a duplicated address of ours. 2030 */ 2031 for (ia = in6_ifaddr; ia; ia = ia->ia_next) 2032 if (IN6_ARE_ADDR_EQUAL(&t, &ia->ia_addr.sin6_addr) && 2033 (ia->ia6_flags & (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY)) == 0) { 2034 src = &t; 2035 break; 2036 } 2037 if (ia == NULL && IN6_IS_ADDR_LINKLOCAL(&t) && (m->m_flags & M_LOOP)) { 2038 /* 2039 * This is the case if the dst is our link-local address 2040 * and the sender is also ourselves. 2041 */ 2042 src = &t; 2043 } 2044 2045 if (src == 0) { 2046 int e; 2047 struct route_in6 ro; 2048 2049 /* 2050 * This case matches to multicasts, our anycast, or unicasts 2051 * that we do not own. Select a source address based on the 2052 * source address of the erroneous packet. 2053 */ 2054 bzero(&ro, sizeof(ro)); 2055 src = in6_selectsrc(&sa6_src, NULL, NULL, &ro, NULL, &e, NULL); 2056 if (ro.ro_rt) 2057 RTFREE(ro.ro_rt); /* XXX: we could use this */ 2058 if (src == NULL) { 2059 nd6log((LOG_DEBUG, 2060 "icmp6_reflect: source can't be determined: " 2061 "dst=%s, error=%d\n", 2062 ip6_sprintf(&sa6_src.sin6_addr), e)); 2063 goto bad; 2064 } 2065 } 2066 2067 ip6->ip6_src = *src; 2068 2069 ip6->ip6_flow = 0; 2070 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2071 ip6->ip6_vfc |= IPV6_VERSION; 2072 ip6->ip6_nxt = IPPROTO_ICMPV6; 2073 if (m->m_pkthdr.rcvif) { 2074 /* XXX: This may not be the outgoing interface */ 2075 ip6->ip6_hlim = ND_IFINFO(m->m_pkthdr.rcvif)->chlim; 2076 } else 2077 ip6->ip6_hlim = ip6_defhlim; 2078 2079 icmp6->icmp6_cksum = 0; 2080 icmp6->icmp6_cksum = in6_cksum(m, IPPROTO_ICMPV6, 2081 sizeof(struct ip6_hdr), plen); 2082 2083 /* 2084 * XXX option handling 2085 */ 2086 2087 m->m_flags &= ~(M_BCAST|M_MCAST); 2088 2089 #ifdef COMPAT_RFC1885 2090 ip6_output(m, NULL, &icmp6_reflect_rt, 0, NULL, &outif, NULL); 2091 #else 2092 ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL); 2093 #endif 2094 if (outif) 2095 icmp6_ifoutstat_inc(outif, type, code); 2096 2097 return; 2098 2099 bad: 2100 m_freem(m); 2101 return; 2102 } 2103 2104 void 2105 icmp6_fasttimo(void) 2106 { 2107 2108 mld6_fasttimeo(); 2109 } 2110 2111 static const char * 2112 icmp6_redirect_diag(struct in6_addr *src6, struct in6_addr *dst6, 2113 struct in6_addr *tgt6) 2114 { 2115 static char buf[1024]; 2116 ksnprintf(buf, sizeof(buf), "(src=%s dst=%s tgt=%s)", 2117 ip6_sprintf(src6), ip6_sprintf(dst6), ip6_sprintf(tgt6)); 2118 return buf; 2119 } 2120 2121 void 2122 icmp6_redirect_input(struct mbuf *m, int off) 2123 { 2124 struct ifnet *ifp = m->m_pkthdr.rcvif; 2125 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 2126 struct nd_redirect *nd_rd; 2127 int icmp6len = ntohs(ip6->ip6_plen); 2128 char *lladdr = NULL; 2129 int lladdrlen = 0; 2130 u_char *redirhdr = NULL; 2131 int redirhdrlen = 0; 2132 struct rtentry *rt = NULL; 2133 int is_router; 2134 int is_onlink; 2135 struct in6_addr src6 = ip6->ip6_src; 2136 struct in6_addr redtgt6; 2137 struct in6_addr reddst6; 2138 union nd_opts ndopts; 2139 2140 if (!m || !ifp) 2141 return; 2142 2143 /* XXX if we are router, we don't update route by icmp6 redirect */ 2144 if (ip6_forwarding) 2145 goto freeit; 2146 if (!icmp6_rediraccept) 2147 goto freeit; 2148 2149 #ifndef PULLDOWN_TEST 2150 IP6_EXTHDR_CHECK(m, off, icmp6len,); 2151 nd_rd = (struct nd_redirect *)((caddr_t)ip6 + off); 2152 #else 2153 IP6_EXTHDR_GET(nd_rd, struct nd_redirect *, m, off, icmp6len); 2154 if (nd_rd == NULL) { 2155 icmp6stat.icp6s_tooshort++; 2156 return; 2157 } 2158 #endif 2159 redtgt6 = nd_rd->nd_rd_target; 2160 reddst6 = nd_rd->nd_rd_dst; 2161 2162 if (IN6_IS_ADDR_LINKLOCAL(&redtgt6)) 2163 redtgt6.s6_addr16[1] = htons(ifp->if_index); 2164 if (IN6_IS_ADDR_LINKLOCAL(&reddst6)) 2165 reddst6.s6_addr16[1] = htons(ifp->if_index); 2166 2167 /* validation */ 2168 if (!IN6_IS_ADDR_LINKLOCAL(&src6)) { 2169 nd6log((LOG_ERR, 2170 "ICMP6 redirect sent from %s rejected; " 2171 "must be from linklocal\n", ip6_sprintf(&src6))); 2172 goto bad; 2173 } 2174 if (ip6->ip6_hlim != 255) { 2175 nd6log((LOG_ERR, 2176 "ICMP6 redirect sent from %s rejected; " 2177 "hlim=%d (must be 255)\n", 2178 ip6_sprintf(&src6), ip6->ip6_hlim)); 2179 goto bad; 2180 } 2181 { 2182 /* ip6->ip6_src must be equal to gw for icmp6->icmp6_reddst */ 2183 struct sockaddr_in6 sin6; 2184 struct in6_addr *gw6; 2185 2186 bzero(&sin6, sizeof(sin6)); 2187 sin6.sin6_family = AF_INET6; 2188 sin6.sin6_len = sizeof(struct sockaddr_in6); 2189 bcopy(&reddst6, &sin6.sin6_addr, sizeof reddst6); 2190 rt = rtpurelookup((struct sockaddr *)&sin6); 2191 if (rt != NULL) { 2192 if (rt->rt_gateway == NULL || 2193 rt->rt_gateway->sa_family != AF_INET6) { 2194 nd6log((LOG_ERR, 2195 "ICMP6 redirect rejected; no route " 2196 "with inet6 gateway found for redirect dst: %s\n", 2197 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2198 --rt->rt_refcnt; 2199 goto bad; 2200 } 2201 2202 gw6 = &(((struct sockaddr_in6 *)rt->rt_gateway)->sin6_addr); 2203 if (bcmp(&src6, gw6, sizeof(struct in6_addr)) != 0) { 2204 nd6log((LOG_ERR, 2205 "ICMP6 redirect rejected; " 2206 "not equal to gw-for-src=%s (must be same): " 2207 "%s\n", 2208 ip6_sprintf(gw6), 2209 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2210 --rt->rt_refcnt; 2211 goto bad; 2212 } 2213 } else { 2214 nd6log((LOG_ERR, 2215 "ICMP6 redirect rejected; " 2216 "no route found for redirect dst: %s\n", 2217 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2218 goto bad; 2219 } 2220 --rt->rt_refcnt; 2221 rt = NULL; 2222 } 2223 if (IN6_IS_ADDR_MULTICAST(&reddst6)) { 2224 nd6log((LOG_ERR, 2225 "ICMP6 redirect rejected; " 2226 "redirect dst must be unicast: %s\n", 2227 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2228 goto bad; 2229 } 2230 2231 is_router = is_onlink = 0; 2232 if (IN6_IS_ADDR_LINKLOCAL(&redtgt6)) 2233 is_router = 1; /* router case */ 2234 if (bcmp(&redtgt6, &reddst6, sizeof(redtgt6)) == 0) 2235 is_onlink = 1; /* on-link destination case */ 2236 if (!is_router && !is_onlink) { 2237 nd6log((LOG_ERR, 2238 "ICMP6 redirect rejected; " 2239 "neither router case nor onlink case: %s\n", 2240 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2241 goto bad; 2242 } 2243 /* validation passed */ 2244 2245 icmp6len -= sizeof(*nd_rd); 2246 nd6_option_init(nd_rd + 1, icmp6len, &ndopts); 2247 if (nd6_options(&ndopts) < 0) { 2248 nd6log((LOG_INFO, "icmp6_redirect_input: " 2249 "invalid ND option, rejected: %s\n", 2250 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2251 /* nd6_options have incremented stats */ 2252 goto freeit; 2253 } 2254 2255 if (ndopts.nd_opts_tgt_lladdr) { 2256 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 2257 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 2258 } 2259 2260 if (ndopts.nd_opts_rh) { 2261 redirhdrlen = ndopts.nd_opts_rh->nd_opt_rh_len; 2262 redirhdr = (u_char *)(ndopts.nd_opts_rh + 1); /* xxx */ 2263 } 2264 2265 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 2266 nd6log((LOG_INFO, 2267 "icmp6_redirect_input: lladdrlen mismatch for %s " 2268 "(if %d, icmp6 packet %d): %s\n", 2269 ip6_sprintf(&redtgt6), ifp->if_addrlen, lladdrlen - 2, 2270 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2271 goto bad; 2272 } 2273 2274 /* RFC 2461 8.3 */ 2275 nd6_cache_lladdr(ifp, &redtgt6, lladdr, lladdrlen, ND_REDIRECT, 2276 is_onlink ? ND_REDIRECT_ONLINK : ND_REDIRECT_ROUTER); 2277 2278 if (!is_onlink) { /* better router case. perform rtredirect. */ 2279 /* perform rtredirect */ 2280 struct sockaddr_in6 sdst; 2281 struct sockaddr_in6 sgw; 2282 struct sockaddr_in6 ssrc; 2283 2284 bzero(&sdst, sizeof(sdst)); 2285 bzero(&sgw, sizeof(sgw)); 2286 bzero(&ssrc, sizeof(ssrc)); 2287 sdst.sin6_family = sgw.sin6_family = ssrc.sin6_family = AF_INET6; 2288 sdst.sin6_len = sgw.sin6_len = ssrc.sin6_len = 2289 sizeof(struct sockaddr_in6); 2290 bcopy(&redtgt6, &sgw.sin6_addr, sizeof(struct in6_addr)); 2291 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2292 bcopy(&src6, &ssrc.sin6_addr, sizeof(struct in6_addr)); 2293 rtredirect((struct sockaddr *)&sdst, (struct sockaddr *)&sgw, 2294 NULL, RTF_GATEWAY | RTF_HOST, 2295 (struct sockaddr *)&ssrc); 2296 } 2297 /* finally update cached route in each socket via kpfctlinput */ 2298 { 2299 struct sockaddr_in6 sdst; 2300 2301 bzero(&sdst, sizeof(sdst)); 2302 sdst.sin6_family = AF_INET6; 2303 sdst.sin6_len = sizeof(struct sockaddr_in6); 2304 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2305 kpfctlinput(PRC_REDIRECT_HOST, (struct sockaddr *)&sdst); 2306 #ifdef IPSEC 2307 key_sa_routechange((struct sockaddr *)&sdst); 2308 #endif 2309 } 2310 2311 freeit: 2312 m_freem(m); 2313 return; 2314 2315 bad: 2316 icmp6stat.icp6s_badredirect++; 2317 m_freem(m); 2318 } 2319 2320 void 2321 icmp6_redirect_output(struct mbuf *m0, struct rtentry *rt) 2322 { 2323 struct ifnet *ifp; /* my outgoing interface */ 2324 struct in6_addr *ifp_ll6; 2325 struct in6_addr *router_ll6; 2326 struct ip6_hdr *sip6; /* m0 as struct ip6_hdr */ 2327 struct mbuf *m = NULL; /* newly allocated one */ 2328 struct ip6_hdr *ip6; /* m as struct ip6_hdr */ 2329 struct nd_redirect *nd_rd; 2330 size_t maxlen; 2331 u_char *p; 2332 struct ifnet *outif = NULL; 2333 struct sockaddr_in6 src_sa; 2334 2335 icmp6_errcount(&icmp6stat.icp6s_outerrhist, ND_REDIRECT, 0); 2336 2337 /* if we are not router, we don't send icmp6 redirect */ 2338 if (!ip6_forwarding || ip6_accept_rtadv) 2339 goto fail; 2340 2341 /* sanity check */ 2342 if (!m0 || !rt || !(rt->rt_flags & RTF_UP) || !(ifp = rt->rt_ifp)) 2343 goto fail; 2344 2345 /* 2346 * Address check: 2347 * the source address must identify a neighbor, and 2348 * the destination address must not be a multicast address 2349 * [RFC 2461, sec 8.2] 2350 */ 2351 sip6 = mtod(m0, struct ip6_hdr *); 2352 bzero(&src_sa, sizeof(src_sa)); 2353 src_sa.sin6_family = AF_INET6; 2354 src_sa.sin6_len = sizeof(src_sa); 2355 src_sa.sin6_addr = sip6->ip6_src; 2356 /* we don't currently use sin6_scope_id, but eventually use it */ 2357 src_sa.sin6_scope_id = in6_addr2scopeid(ifp, &sip6->ip6_src); 2358 if (nd6_is_addr_neighbor(&src_sa, ifp) == 0) 2359 goto fail; 2360 if (IN6_IS_ADDR_MULTICAST(&sip6->ip6_dst)) 2361 goto fail; /* what should we do here? */ 2362 2363 /* rate limit */ 2364 if (icmp6_ratelimit(&sip6->ip6_src, ND_REDIRECT, 0)) 2365 goto fail; 2366 2367 /* 2368 * Since we are going to append up to 1280 bytes (= IPV6_MMTU), 2369 * we almost always ask for an mbuf cluster for simplicity. 2370 * (MHLEN < IPV6_MMTU is almost always true) 2371 */ 2372 #if IPV6_MMTU >= MCLBYTES 2373 # error assumption failed about IPV6_MMTU and MCLBYTES 2374 #endif 2375 m = m_getb(IPV6_MMTU, MB_DONTWAIT, MT_HEADER, M_PKTHDR); 2376 if (!m) 2377 goto fail; 2378 m->m_len = 0; 2379 maxlen = M_TRAILINGSPACE(m); 2380 maxlen = min(IPV6_MMTU, maxlen); 2381 /* just for safety */ 2382 if (maxlen < sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) + 2383 ((sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7)) { 2384 goto fail; 2385 } 2386 2387 { 2388 /* get ip6 linklocal address for ifp(my outgoing interface). */ 2389 struct in6_ifaddr *ia; 2390 if ((ia = in6ifa_ifpforlinklocal(ifp, 2391 IN6_IFF_NOTREADY| 2392 IN6_IFF_ANYCAST)) == NULL) 2393 goto fail; 2394 ifp_ll6 = &ia->ia_addr.sin6_addr; 2395 } 2396 2397 /* get ip6 linklocal address for the router. */ 2398 if (rt->rt_gateway && (rt->rt_flags & RTF_GATEWAY)) { 2399 struct sockaddr_in6 *sin6; 2400 sin6 = (struct sockaddr_in6 *)rt->rt_gateway; 2401 router_ll6 = &sin6->sin6_addr; 2402 if (!IN6_IS_ADDR_LINKLOCAL(router_ll6)) 2403 router_ll6 = NULL; 2404 } else 2405 router_ll6 = NULL; 2406 2407 /* ip6 */ 2408 ip6 = mtod(m, struct ip6_hdr *); 2409 ip6->ip6_flow = 0; 2410 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2411 ip6->ip6_vfc |= IPV6_VERSION; 2412 /* ip6->ip6_plen will be set later */ 2413 ip6->ip6_nxt = IPPROTO_ICMPV6; 2414 ip6->ip6_hlim = 255; 2415 /* ip6->ip6_src must be linklocal addr for my outgoing if. */ 2416 bcopy(ifp_ll6, &ip6->ip6_src, sizeof(struct in6_addr)); 2417 bcopy(&sip6->ip6_src, &ip6->ip6_dst, sizeof(struct in6_addr)); 2418 2419 /* ND Redirect */ 2420 nd_rd = (struct nd_redirect *)(ip6 + 1); 2421 nd_rd->nd_rd_type = ND_REDIRECT; 2422 nd_rd->nd_rd_code = 0; 2423 nd_rd->nd_rd_reserved = 0; 2424 if (rt->rt_flags & RTF_GATEWAY) { 2425 /* 2426 * nd_rd->nd_rd_target must be a link-local address in 2427 * better router cases. 2428 */ 2429 if (!router_ll6) 2430 goto fail; 2431 bcopy(router_ll6, &nd_rd->nd_rd_target, 2432 sizeof(nd_rd->nd_rd_target)); 2433 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2434 sizeof(nd_rd->nd_rd_dst)); 2435 } else { 2436 /* make sure redtgt == reddst */ 2437 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_target, 2438 sizeof(nd_rd->nd_rd_target)); 2439 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2440 sizeof(nd_rd->nd_rd_dst)); 2441 } 2442 2443 p = (u_char *)(nd_rd + 1); 2444 2445 if (!router_ll6) 2446 goto nolladdropt; 2447 2448 { 2449 /* target lladdr option */ 2450 struct rtentry *rt_router = NULL; 2451 int len; 2452 struct sockaddr_dl *sdl; 2453 struct nd_opt_hdr *nd_opt; 2454 char *lladdr; 2455 2456 rt_router = nd6_lookup(router_ll6, 0, ifp); 2457 if (!rt_router) 2458 goto nolladdropt; 2459 len = sizeof(*nd_opt) + ifp->if_addrlen; 2460 len = (len + 7) & ~7; /* round by 8 */ 2461 /* safety check */ 2462 if (len + (p - (u_char *)ip6) > maxlen) 2463 goto nolladdropt; 2464 if (!(rt_router->rt_flags & RTF_GATEWAY) && 2465 (rt_router->rt_flags & RTF_LLINFO) && 2466 (rt_router->rt_gateway->sa_family == AF_LINK) && 2467 (sdl = (struct sockaddr_dl *)rt_router->rt_gateway) && 2468 sdl->sdl_alen) { 2469 nd_opt = (struct nd_opt_hdr *)p; 2470 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 2471 nd_opt->nd_opt_len = len >> 3; 2472 lladdr = (char *)(nd_opt + 1); 2473 bcopy(LLADDR(sdl), lladdr, ifp->if_addrlen); 2474 p += len; 2475 } 2476 } 2477 nolladdropt:; 2478 2479 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2480 2481 /* just to be safe */ 2482 #ifdef M_DECRYPTED /*not openbsd*/ 2483 if (m0->m_flags & M_DECRYPTED) 2484 goto noredhdropt; 2485 #endif 2486 if (p - (u_char *)ip6 > maxlen) 2487 goto noredhdropt; 2488 2489 { 2490 /* redirected header option */ 2491 int len; 2492 struct nd_opt_rd_hdr *nd_opt_rh; 2493 2494 /* 2495 * compute the maximum size for icmp6 redirect header option. 2496 * XXX room for auth header? 2497 */ 2498 len = maxlen - (p - (u_char *)ip6); 2499 len &= ~7; 2500 2501 /* This is just for simplicity. */ 2502 if (m0->m_pkthdr.len != m0->m_len) { 2503 if (m0->m_next) { 2504 m_freem(m0->m_next); 2505 m0->m_next = NULL; 2506 } 2507 m0->m_pkthdr.len = m0->m_len; 2508 } 2509 2510 /* 2511 * Redirected header option spec (RFC2461 4.6.3) talks nothing 2512 * about padding/truncate rule for the original IP packet. 2513 * From the discussion on IPv6imp in Feb 1999, the consensus was: 2514 * - "attach as much as possible" is the goal 2515 * - pad if not aligned (original size can be guessed by original 2516 * ip6 header) 2517 * Following code adds the padding if it is simple enough, 2518 * and truncates if not. 2519 */ 2520 if (m0->m_next || m0->m_pkthdr.len != m0->m_len) 2521 panic("assumption failed in %s:%d", __FILE__, __LINE__); 2522 2523 if (len - sizeof(*nd_opt_rh) < m0->m_pkthdr.len) { 2524 /* not enough room, truncate */ 2525 m0->m_pkthdr.len = m0->m_len = len - sizeof(*nd_opt_rh); 2526 } else { 2527 /* enough room, pad or truncate */ 2528 size_t extra; 2529 2530 extra = m0->m_pkthdr.len % 8; 2531 if (extra) { 2532 /* pad if easy enough, truncate if not */ 2533 if (8 - extra <= M_TRAILINGSPACE(m0)) { 2534 /* pad */ 2535 m0->m_len += (8 - extra); 2536 m0->m_pkthdr.len += (8 - extra); 2537 } else { 2538 /* truncate */ 2539 m0->m_pkthdr.len -= extra; 2540 m0->m_len -= extra; 2541 } 2542 } 2543 len = m0->m_pkthdr.len + sizeof(*nd_opt_rh); 2544 m0->m_pkthdr.len = m0->m_len = len - sizeof(*nd_opt_rh); 2545 } 2546 2547 nd_opt_rh = (struct nd_opt_rd_hdr *)p; 2548 bzero(nd_opt_rh, sizeof(*nd_opt_rh)); 2549 nd_opt_rh->nd_opt_rh_type = ND_OPT_REDIRECTED_HEADER; 2550 nd_opt_rh->nd_opt_rh_len = len >> 3; 2551 p += sizeof(*nd_opt_rh); 2552 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2553 2554 /* connect m0 to m */ 2555 m->m_next = m0; 2556 m->m_pkthdr.len = m->m_len + m0->m_len; 2557 } 2558 noredhdropt:; 2559 2560 if (IN6_IS_ADDR_LINKLOCAL(&sip6->ip6_src)) 2561 sip6->ip6_src.s6_addr16[1] = 0; 2562 if (IN6_IS_ADDR_LINKLOCAL(&sip6->ip6_dst)) 2563 sip6->ip6_dst.s6_addr16[1] = 0; 2564 #if 0 2565 if (IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_src)) 2566 ip6->ip6_src.s6_addr16[1] = 0; 2567 if (IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_dst)) 2568 ip6->ip6_dst.s6_addr16[1] = 0; 2569 #endif 2570 if (IN6_IS_ADDR_LINKLOCAL(&nd_rd->nd_rd_target)) 2571 nd_rd->nd_rd_target.s6_addr16[1] = 0; 2572 if (IN6_IS_ADDR_LINKLOCAL(&nd_rd->nd_rd_dst)) 2573 nd_rd->nd_rd_dst.s6_addr16[1] = 0; 2574 2575 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr)); 2576 2577 nd_rd->nd_rd_cksum = 0; 2578 nd_rd->nd_rd_cksum 2579 = in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), ntohs(ip6->ip6_plen)); 2580 2581 /* send the packet to outside... */ 2582 ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL); 2583 if (outif) { 2584 icmp6_ifstat_inc(outif, ifs6_out_msg); 2585 icmp6_ifstat_inc(outif, ifs6_out_redirect); 2586 } 2587 icmp6stat.icp6s_outhist[ND_REDIRECT]++; 2588 2589 return; 2590 2591 fail: 2592 if (m) 2593 m_freem(m); 2594 if (m0) 2595 m_freem(m0); 2596 } 2597 2598 #ifdef HAVE_NRL_INPCB 2599 #define in6pcb inpcb 2600 #define in6p_icmp6filt inp_icmp6filt 2601 #endif 2602 /* 2603 * ICMPv6 socket option processing. 2604 */ 2605 int 2606 icmp6_ctloutput(struct socket *so, struct sockopt *sopt) 2607 { 2608 int error = 0; 2609 int optlen; 2610 struct inpcb *inp = so->so_pcb; 2611 int level, op, optname; 2612 2613 if (sopt) { 2614 level = sopt->sopt_level; 2615 op = sopt->sopt_dir; 2616 optname = sopt->sopt_name; 2617 optlen = sopt->sopt_valsize; 2618 } else 2619 level = op = optname = optlen = 0; 2620 2621 if (level != IPPROTO_ICMPV6) { 2622 return EINVAL; 2623 } 2624 2625 switch (op) { 2626 case PRCO_SETOPT: 2627 switch (optname) { 2628 case ICMP6_FILTER: 2629 { 2630 struct icmp6_filter *p; 2631 2632 if (optlen != sizeof(*p)) { 2633 error = EMSGSIZE; 2634 break; 2635 } 2636 if (inp->in6p_icmp6filt == NULL) { 2637 error = EINVAL; 2638 break; 2639 } 2640 error = soopt_to_kbuf(sopt, inp->in6p_icmp6filt, optlen, 2641 optlen); 2642 break; 2643 } 2644 2645 default: 2646 error = ENOPROTOOPT; 2647 break; 2648 } 2649 break; 2650 2651 case PRCO_GETOPT: 2652 switch (optname) { 2653 case ICMP6_FILTER: 2654 { 2655 if (inp->in6p_icmp6filt == NULL) { 2656 error = EINVAL; 2657 break; 2658 } 2659 soopt_from_kbuf(sopt, inp->in6p_icmp6filt, 2660 sizeof(struct icmp6_filter)); 2661 break; 2662 } 2663 2664 default: 2665 error = ENOPROTOOPT; 2666 break; 2667 } 2668 break; 2669 } 2670 2671 return (error); 2672 } 2673 #ifdef HAVE_NRL_INPCB 2674 #undef in6pcb 2675 #undef in6p_icmp6filt 2676 #endif 2677 2678 #ifndef HAVE_PPSRATECHECK 2679 #ifndef timersub 2680 #define timersub(tvp, uvp, vvp) \ 2681 do { \ 2682 (vvp)->tv_sec = (tvp)->tv_sec - (uvp)->tv_sec; \ 2683 (vvp)->tv_usec = (tvp)->tv_usec - (uvp)->tv_usec; \ 2684 if ((vvp)->tv_usec < 0) { \ 2685 (vvp)->tv_sec--; \ 2686 (vvp)->tv_usec += 1000000; \ 2687 } \ 2688 } while (0) 2689 #endif 2690 2691 /* 2692 * ppsratecheck(): packets (or events) per second limitation. 2693 */ 2694 static int 2695 ppsratecheck(struct timeval *lasttime, int *curpps, 2696 int maxpps) /* maximum pps allowed */ 2697 { 2698 struct timeval tv, delta; 2699 int rv; 2700 2701 microtime(&tv); 2702 2703 timersub(&tv, lasttime, &delta); 2704 2705 /* 2706 * Check for 0,0 so that the message will be seen at least once. 2707 * If more than one second has passed since the last update of 2708 * lasttime, reset the counter. 2709 * 2710 * We do increment *curpps even in *curpps < maxpps case, as some may 2711 * try to use *curpps for stat purposes as well. 2712 */ 2713 if ((lasttime->tv_sec == 0 && lasttime->tv_usec == 0) || 2714 delta.tv_sec >= 1) { 2715 *lasttime = tv; 2716 *curpps = 0; 2717 rv = 1; 2718 } else if (maxpps < 0) 2719 rv = 1; 2720 else if (*curpps < maxpps) 2721 rv = 1; 2722 else 2723 rv = 0; 2724 2725 #if 1 /* DIAGNOSTIC? */ 2726 /* be careful about wrap-around */ 2727 if (*curpps + 1 > *curpps) 2728 *curpps = *curpps + 1; 2729 #else 2730 /* 2731 * assume that there's not too many calls to this function. 2732 * not sure if the assumption holds, as it depends on *caller's* 2733 * behavior, not the behavior of this function. 2734 * IMHO it is wrong to make assumption on the caller's behavior, 2735 * so the above #if is #if 1, not #ifdef DIAGNOSTIC. 2736 */ 2737 *curpps = *curpps + 1; 2738 #endif 2739 2740 return (rv); 2741 } 2742 #endif 2743 2744 /* 2745 * Perform rate limit check. 2746 * Returns 0 if it is okay to send the icmp6 packet. 2747 * Returns 1 if the router SHOULD NOT send this icmp6 packet due to rate 2748 * limitation. 2749 * 2750 * XXX per-destination/type check necessary? 2751 */ 2752 static int 2753 icmp6_ratelimit(const struct in6_addr *dst, /* not used at this moment */ 2754 const int type, /* not used at this moment */ 2755 const int code) /* not used at this moment */ 2756 { 2757 int ret; 2758 2759 ret = 0; /* okay to send */ 2760 2761 /* PPS limit */ 2762 if (!ppsratecheck(&icmp6errppslim_last, &icmp6errpps_count, 2763 icmp6errppslim)) { 2764 /* The packet is subject to rate limit */ 2765 ret++; 2766 } 2767 2768 return ret; 2769 } 2770