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 1.18 2005/02/08 22:56:19 hsu Exp $ */ 3 /* $KAME: icmp6.c,v 1.211 2001/04/04 05:56:20 itojun Exp $ */ 4 5 /* 6 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 7 * All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. Neither the name of the project nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 /* 35 * Copyright (c) 1982, 1986, 1988, 1993 36 * The Regents of the University of California. All rights reserved. 37 * 38 * Redistribution and use in source and binary forms, with or without 39 * modification, are permitted provided that the following conditions 40 * are met: 41 * 1. Redistributions of source code must retain the above copyright 42 * notice, this list of conditions and the following disclaimer. 43 * 2. Redistributions in binary form must reproduce the above copyright 44 * notice, this list of conditions and the following disclaimer in the 45 * documentation and/or other materials provided with the distribution. 46 * 3. All advertising materials mentioning features or use of this software 47 * must display the following acknowledgement: 48 * This product includes software developed by the University of 49 * California, Berkeley and its contributors. 50 * 4. Neither the name of the University nor the names of its contributors 51 * may be used to endorse or promote products derived from this software 52 * without specific prior written permission. 53 * 54 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 55 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 56 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 57 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 58 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 59 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 60 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 61 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 62 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 63 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 64 * SUCH DAMAGE. 65 * 66 * @(#)ip_icmp.c 8.2 (Berkeley) 1/4/94 67 */ 68 69 #include "opt_inet.h" 70 #include "opt_inet6.h" 71 #include "opt_ipsec.h" 72 73 #include <sys/param.h> 74 #include <sys/systm.h> 75 #include <sys/malloc.h> 76 #include <sys/mbuf.h> 77 #include <sys/protosw.h> 78 #include <sys/socket.h> 79 #include <sys/socketvar.h> 80 #include <sys/time.h> 81 #include <sys/kernel.h> 82 #include <sys/syslog.h> 83 #include <sys/domain.h> 84 85 #include <net/if.h> 86 #include <net/route.h> 87 #include <net/if_dl.h> 88 #include <net/if_types.h> 89 90 #include <netinet/in.h> 91 #include <netinet/in_var.h> 92 #include <netinet/ip6.h> 93 #include <netinet6/ip6_var.h> 94 #include <netinet/icmp6.h> 95 #include <netinet6/mld6_var.h> 96 #include <netinet/in_pcb.h> 97 #include <netinet6/in6_pcb.h> 98 #include <netinet6/nd6.h> 99 #include <netinet6/in6_ifattach.h> 100 #include <netinet6/ip6protosw.h> 101 102 #ifdef IPSEC 103 #include <netinet6/ipsec.h> 104 #include <netproto/key/key.h> 105 #endif 106 107 #ifdef FAST_IPSEC 108 #include <netproto/ipsec/ipsec.h> 109 #include <netproto/ipsec/key.h> 110 #define IPSEC 111 #endif 112 113 #include <net/net_osdep.h> 114 115 #ifdef HAVE_NRL_INPCB 116 /* inpcb members */ 117 #define in6pcb inpcb 118 #define in6p_laddr inp_laddr6 119 #define in6p_faddr inp_faddr6 120 #define in6p_icmp6filt inp_icmp6filt 121 #define in6p_route inp_route 122 #define in6p_socket inp_socket 123 #define in6p_flags inp_flags 124 #define in6p_moptions inp_moptions6 125 #define in6p_outputopts inp_outputopts6 126 #define in6p_ip6 inp_ipv6 127 #define in6p_flowinfo inp_flowinfo 128 #define in6p_sp inp_sp 129 #define in6p_next inp_next 130 #define in6p_prev inp_prev 131 /* 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) != 0 547 || 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 MGETHDR(n, MB_DONTWAIT, n0->m_type); 562 n0len = n0->m_pkthdr.len; /* save for use below */ 563 if (n) 564 M_MOVE_PKTHDR(n, n0); 565 if (n && maxlen >= MHLEN) { 566 MCLGET(n, MB_DONTWAIT); 567 if ((n->m_flags & M_EXT) == 0) { 568 m_free(n); 569 n = NULL; 570 } 571 } 572 if (n == NULL) { 573 /* Give up remote */ 574 m_freem(n0); 575 break; 576 } 577 /* 578 * Copy IPv6 and ICMPv6 only. 579 */ 580 nip6 = mtod(n, struct ip6_hdr *); 581 bcopy(ip6, nip6, sizeof(struct ip6_hdr)); 582 nicmp6 = (struct icmp6_hdr *)(nip6 + 1); 583 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr)); 584 noff = sizeof(struct ip6_hdr); 585 /* new mbuf contains only ipv6+icmpv6 headers */ 586 n->m_len = noff + sizeof(struct icmp6_hdr); 587 /* 588 * Adjust mbuf. ip6_plen will be adjusted in 589 * ip6_output(). 590 */ 591 m_adj(n0, off + sizeof(struct icmp6_hdr)); 592 /* recalculate complete packet size */ 593 n->m_pkthdr.len = n0len + (noff - off); 594 n->m_next = n0; 595 } else { 596 nip6 = mtod(n, struct ip6_hdr *); 597 nicmp6 = (struct icmp6_hdr *)((caddr_t)nip6 + off); 598 noff = off; 599 } 600 nicmp6->icmp6_type = ICMP6_ECHO_REPLY; 601 nicmp6->icmp6_code = 0; 602 if (n) { 603 icmp6stat.icp6s_reflect++; 604 icmp6stat.icp6s_outhist[ICMP6_ECHO_REPLY]++; 605 icmp6_reflect(n, noff); 606 } 607 break; 608 609 case ICMP6_ECHO_REPLY: 610 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echoreply); 611 if (code != 0) 612 goto badcode; 613 break; 614 615 case MLD_LISTENER_QUERY: 616 case MLD_LISTENER_REPORT: 617 if (icmp6len < sizeof(struct mld_hdr)) 618 goto badlen; 619 if (icmp6->icmp6_type == MLD_LISTENER_QUERY) /* XXX: ugly... */ 620 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldquery); 621 else 622 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldreport); 623 if ((n = m_copym(m, 0, M_COPYALL, MB_DONTWAIT)) == NULL) { 624 /* give up local */ 625 mld6_input(m, off); 626 m = NULL; 627 goto freeit; 628 } 629 mld6_input(n, off); 630 /* m stays. */ 631 break; 632 633 case MLD_LISTENER_DONE: 634 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mlddone); 635 if (icmp6len < sizeof(struct mld_hdr)) /* necessary? */ 636 goto badlen; 637 break; /* nothing to be done in kernel */ 638 639 case MLD_MTRACE_RESP: 640 case MLD_MTRACE: 641 /* XXX: these two are experimental. not officially defind. */ 642 /* XXX: per-interface statistics? */ 643 break; /* just pass it to applications */ 644 645 case ICMP6_WRUREQUEST: /* ICMP6_FQDN_QUERY */ 646 { 647 enum { WRU, FQDN } mode; 648 649 if (!icmp6_nodeinfo) 650 break; 651 652 if (icmp6len == sizeof(struct icmp6_hdr) + 4) 653 mode = WRU; 654 else if (icmp6len >= sizeof(struct icmp6_nodeinfo)) 655 mode = FQDN; 656 else 657 goto badlen; 658 659 #define hostnamelen strlen(hostname) 660 if (mode == FQDN) { 661 #ifndef PULLDOWN_TEST 662 IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_nodeinfo), 663 IPPROTO_DONE); 664 #endif 665 n = m_copy(m, 0, M_COPYALL); 666 if (n) 667 n = ni6_input(n, off); 668 /* XXX meaningless if n == NULL */ 669 noff = sizeof(struct ip6_hdr); 670 } else { 671 u_char *p; 672 int maxlen, maxhlen; 673 674 if ((icmp6_nodeinfo & 5) != 5) 675 break; 676 677 if (code != 0) 678 goto badcode; 679 maxlen = sizeof(*nip6) + sizeof(*nicmp6) + 4; 680 if (maxlen >= MCLBYTES) { 681 /* Give up remote */ 682 break; 683 } 684 MGETHDR(n, MB_DONTWAIT, m->m_type); 685 if (n && maxlen > MHLEN) { 686 MCLGET(n, MB_DONTWAIT); 687 if ((n->m_flags & M_EXT) == 0) { 688 m_free(n); 689 n = NULL; 690 } 691 } 692 if (!m_dup_pkthdr(n, m, MB_DONTWAIT)) { 693 /* 694 * Previous code did a blind M_COPY_PKTHDR 695 * and said "just for rcvif". If true, then 696 * we could tolerate the dup failing (due to 697 * the deep copy of the tag chain). For now 698 * be conservative and just fail. 699 */ 700 m_free(n); 701 n = NULL; 702 } 703 if (n == NULL) { 704 /* Give up remote */ 705 break; 706 } 707 n->m_pkthdr.rcvif = NULL; 708 n->m_len = 0; 709 maxhlen = M_TRAILINGSPACE(n) - maxlen; 710 if (maxhlen > hostnamelen) 711 maxhlen = hostnamelen; 712 /* 713 * Copy IPv6 and ICMPv6 only. 714 */ 715 nip6 = mtod(n, struct ip6_hdr *); 716 bcopy(ip6, nip6, sizeof(struct ip6_hdr)); 717 nicmp6 = (struct icmp6_hdr *)(nip6 + 1); 718 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr)); 719 p = (u_char *)(nicmp6 + 1); 720 bzero(p, 4); 721 bcopy(hostname, p + 4, maxhlen); /* meaningless TTL */ 722 noff = sizeof(struct ip6_hdr); 723 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) + 724 sizeof(struct icmp6_hdr) + 4 + maxhlen; 725 nicmp6->icmp6_type = ICMP6_WRUREPLY; 726 nicmp6->icmp6_code = 0; 727 } 728 #undef hostnamelen 729 if (n) { 730 icmp6stat.icp6s_reflect++; 731 icmp6stat.icp6s_outhist[ICMP6_WRUREPLY]++; 732 icmp6_reflect(n, noff); 733 } 734 break; 735 } 736 737 case ICMP6_WRUREPLY: 738 if (code != 0) 739 goto badcode; 740 break; 741 742 case ND_ROUTER_SOLICIT: 743 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routersolicit); 744 if (code != 0) 745 goto badcode; 746 if (icmp6len < sizeof(struct nd_router_solicit)) 747 goto badlen; 748 if ((n = m_copym(m, 0, M_COPYALL, MB_DONTWAIT)) == NULL) { 749 /* give up local */ 750 nd6_rs_input(m, off, icmp6len); 751 m = NULL; 752 goto freeit; 753 } 754 nd6_rs_input(n, off, icmp6len); 755 /* m stays. */ 756 break; 757 758 case ND_ROUTER_ADVERT: 759 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routeradvert); 760 if (code != 0) 761 goto badcode; 762 if (icmp6len < sizeof(struct nd_router_advert)) 763 goto badlen; 764 if ((n = m_copym(m, 0, M_COPYALL, MB_DONTWAIT)) == NULL) { 765 /* give up local */ 766 nd6_ra_input(m, off, icmp6len); 767 m = NULL; 768 goto freeit; 769 } 770 nd6_ra_input(n, off, icmp6len); 771 /* m stays. */ 772 break; 773 774 case ND_NEIGHBOR_SOLICIT: 775 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighborsolicit); 776 if (code != 0) 777 goto badcode; 778 if (icmp6len < sizeof(struct nd_neighbor_solicit)) 779 goto badlen; 780 if ((n = m_copym(m, 0, M_COPYALL, MB_DONTWAIT)) == NULL) { 781 /* give up local */ 782 nd6_ns_input(m, off, icmp6len); 783 m = NULL; 784 goto freeit; 785 } 786 nd6_ns_input(n, off, icmp6len); 787 /* m stays. */ 788 break; 789 790 case ND_NEIGHBOR_ADVERT: 791 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighboradvert); 792 if (code != 0) 793 goto badcode; 794 if (icmp6len < sizeof(struct nd_neighbor_advert)) 795 goto badlen; 796 if ((n = m_copym(m, 0, M_COPYALL, MB_DONTWAIT)) == NULL) { 797 /* give up local */ 798 nd6_na_input(m, off, icmp6len); 799 m = NULL; 800 goto freeit; 801 } 802 nd6_na_input(n, off, icmp6len); 803 /* m stays. */ 804 break; 805 806 case ND_REDIRECT: 807 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_redirect); 808 if (code != 0) 809 goto badcode; 810 if (icmp6len < sizeof(struct nd_redirect)) 811 goto badlen; 812 if ((n = m_copym(m, 0, M_COPYALL, MB_DONTWAIT)) == NULL) { 813 /* give up local */ 814 icmp6_redirect_input(m, off); 815 m = NULL; 816 goto freeit; 817 } 818 icmp6_redirect_input(n, off); 819 /* m stays. */ 820 break; 821 822 case ICMP6_ROUTER_RENUMBERING: 823 if (code != ICMP6_ROUTER_RENUMBERING_COMMAND && 824 code != ICMP6_ROUTER_RENUMBERING_RESULT) 825 goto badcode; 826 if (icmp6len < sizeof(struct icmp6_router_renum)) 827 goto badlen; 828 break; 829 830 default: 831 nd6log((LOG_DEBUG, 832 "icmp6_input: unknown type %d(src=%s, dst=%s, ifid=%d)\n", 833 icmp6->icmp6_type, ip6_sprintf(&ip6->ip6_src), 834 ip6_sprintf(&ip6->ip6_dst), 835 m->m_pkthdr.rcvif ? m->m_pkthdr.rcvif->if_index : 0)); 836 if (icmp6->icmp6_type < ICMP6_ECHO_REQUEST) { 837 /* ICMPv6 error: MUST deliver it by spec... */ 838 code = PRC_NCMDS; 839 /* deliver */ 840 } else { 841 /* ICMPv6 informational: MUST not deliver */ 842 break; 843 } 844 deliver: 845 if (icmp6_notify_error(m, off, icmp6len, code)) { 846 /* In this case, m should've been freed. */ 847 return(IPPROTO_DONE); 848 } 849 break; 850 851 badcode: 852 icmp6stat.icp6s_badcode++; 853 break; 854 855 badlen: 856 icmp6stat.icp6s_badlen++; 857 break; 858 } 859 860 /* deliver the packet to appropriate sockets */ 861 icmp6_rip6_input(&m, *offp); 862 863 return IPPROTO_DONE; 864 865 freeit: 866 m_freem(m); 867 return IPPROTO_DONE; 868 } 869 870 static int 871 icmp6_notify_error(struct mbuf *m, int off, int icmp6len, int code) 872 { 873 struct icmp6_hdr *icmp6; 874 struct ip6_hdr *eip6; 875 u_int32_t notifymtu; 876 struct sockaddr_in6 icmp6src, icmp6dst; 877 878 if (icmp6len < sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr)) { 879 icmp6stat.icp6s_tooshort++; 880 goto freeit; 881 } 882 #ifndef PULLDOWN_TEST 883 IP6_EXTHDR_CHECK(m, off, 884 sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr), 885 -1); 886 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 887 #else 888 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, 889 sizeof(*icmp6) + sizeof(struct ip6_hdr)); 890 if (icmp6 == NULL) { 891 icmp6stat.icp6s_tooshort++; 892 return(-1); 893 } 894 #endif 895 eip6 = (struct ip6_hdr *)(icmp6 + 1); 896 897 /* Detect the upper level protocol */ 898 { 899 void (*ctlfunc) (int, struct sockaddr *, void *); 900 u_int8_t nxt = eip6->ip6_nxt; 901 int eoff = off + sizeof(struct icmp6_hdr) + 902 sizeof(struct ip6_hdr); 903 struct ip6ctlparam ip6cp; 904 struct in6_addr *finaldst = NULL; 905 int icmp6type = icmp6->icmp6_type; 906 struct ip6_frag *fh; 907 struct ip6_rthdr *rth; 908 struct ip6_rthdr0 *rth0; 909 int rthlen; 910 911 while (1) { /* XXX: should avoid infinite loop explicitly? */ 912 struct ip6_ext *eh; 913 914 switch (nxt) { 915 case IPPROTO_HOPOPTS: 916 case IPPROTO_DSTOPTS: 917 case IPPROTO_AH: 918 #ifndef PULLDOWN_TEST 919 IP6_EXTHDR_CHECK(m, 0, eoff + 920 sizeof(struct ip6_ext), 921 -1); 922 eh = (struct ip6_ext *)(mtod(m, caddr_t) 923 + eoff); 924 #else 925 IP6_EXTHDR_GET(eh, struct ip6_ext *, m, 926 eoff, sizeof(*eh)); 927 if (eh == NULL) { 928 icmp6stat.icp6s_tooshort++; 929 return(-1); 930 } 931 #endif 932 933 if (nxt == IPPROTO_AH) 934 eoff += (eh->ip6e_len + 2) << 2; 935 else 936 eoff += (eh->ip6e_len + 1) << 3; 937 nxt = eh->ip6e_nxt; 938 break; 939 case IPPROTO_ROUTING: 940 /* 941 * When the erroneous packet contains a 942 * routing header, we should examine the 943 * header to determine the final destination. 944 * Otherwise, we can't properly update 945 * information that depends on the final 946 * destination (e.g. path MTU). 947 */ 948 #ifndef PULLDOWN_TEST 949 IP6_EXTHDR_CHECK(m, 0, eoff + sizeof(*rth), 950 -1); 951 rth = (struct ip6_rthdr *)(mtod(m, caddr_t) 952 + eoff); 953 #else 954 IP6_EXTHDR_GET(rth, struct ip6_rthdr *, m, 955 eoff, sizeof(*rth)); 956 if (rth == NULL) { 957 icmp6stat.icp6s_tooshort++; 958 return(-1); 959 } 960 #endif 961 rthlen = (rth->ip6r_len + 1) << 3; 962 /* 963 * XXX: currently there is no 964 * officially defined type other 965 * than type-0. 966 * Note that if the segment left field 967 * is 0, all intermediate hops must 968 * have been passed. 969 */ 970 if (rth->ip6r_segleft && 971 rth->ip6r_type == IPV6_RTHDR_TYPE_0) { 972 int hops; 973 974 #ifndef PULLDOWN_TEST 975 IP6_EXTHDR_CHECK(m, 0, eoff + rthlen, 976 -1); 977 rth0 = (struct ip6_rthdr0 *)(mtod(m, caddr_t) + eoff); 978 #else 979 IP6_EXTHDR_GET(rth0, 980 struct ip6_rthdr0 *, m, 981 eoff, rthlen); 982 if (rth0 == NULL) { 983 icmp6stat.icp6s_tooshort++; 984 return(-1); 985 } 986 #endif 987 /* just ignore a bogus header */ 988 if ((rth0->ip6r0_len % 2) == 0 && 989 (hops = rth0->ip6r0_len/2)) 990 finaldst = (struct in6_addr *)(rth0 + 1) + (hops - 1); 991 } 992 eoff += rthlen; 993 nxt = rth->ip6r_nxt; 994 break; 995 case IPPROTO_FRAGMENT: 996 #ifndef PULLDOWN_TEST 997 IP6_EXTHDR_CHECK(m, 0, eoff + 998 sizeof(struct ip6_frag), 999 -1); 1000 fh = (struct ip6_frag *)(mtod(m, caddr_t) 1001 + eoff); 1002 #else 1003 IP6_EXTHDR_GET(fh, struct ip6_frag *, m, 1004 eoff, sizeof(*fh)); 1005 if (fh == NULL) { 1006 icmp6stat.icp6s_tooshort++; 1007 return(-1); 1008 } 1009 #endif 1010 /* 1011 * Data after a fragment header is meaningless 1012 * unless it is the first fragment, but 1013 * we'll go to the notify label for path MTU 1014 * discovery. 1015 */ 1016 if (fh->ip6f_offlg & IP6F_OFF_MASK) 1017 goto notify; 1018 1019 eoff += sizeof(struct ip6_frag); 1020 nxt = fh->ip6f_nxt; 1021 break; 1022 default: 1023 /* 1024 * This case includes ESP and the No Next 1025 * Header. In such cases going to the notify 1026 * label does not have any meaning 1027 * (i.e. ctlfunc will be NULL), but we go 1028 * anyway since we might have to update 1029 * path MTU information. 1030 */ 1031 goto notify; 1032 } 1033 } 1034 notify: 1035 #ifndef PULLDOWN_TEST 1036 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 1037 #else 1038 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, 1039 sizeof(*icmp6) + sizeof(struct ip6_hdr)); 1040 if (icmp6 == NULL) { 1041 icmp6stat.icp6s_tooshort++; 1042 return(-1); 1043 } 1044 #endif 1045 1046 eip6 = (struct ip6_hdr *)(icmp6 + 1); 1047 bzero(&icmp6dst, sizeof(icmp6dst)); 1048 icmp6dst.sin6_len = sizeof(struct sockaddr_in6); 1049 icmp6dst.sin6_family = AF_INET6; 1050 if (finaldst == NULL) 1051 icmp6dst.sin6_addr = eip6->ip6_dst; 1052 else 1053 icmp6dst.sin6_addr = *finaldst; 1054 icmp6dst.sin6_scope_id = in6_addr2scopeid(m->m_pkthdr.rcvif, 1055 &icmp6dst.sin6_addr); 1056 if (in6_embedscope(&icmp6dst.sin6_addr, &icmp6dst, 1057 NULL, NULL)) { 1058 /* should be impossbile */ 1059 nd6log((LOG_DEBUG, 1060 "icmp6_notify_error: in6_embedscope failed\n")); 1061 goto freeit; 1062 } 1063 1064 /* 1065 * retrieve parameters from the inner IPv6 header, and convert 1066 * them into sockaddr structures. 1067 */ 1068 bzero(&icmp6src, sizeof(icmp6src)); 1069 icmp6src.sin6_len = sizeof(struct sockaddr_in6); 1070 icmp6src.sin6_family = AF_INET6; 1071 icmp6src.sin6_addr = eip6->ip6_src; 1072 icmp6src.sin6_scope_id = in6_addr2scopeid(m->m_pkthdr.rcvif, 1073 &icmp6src.sin6_addr); 1074 if (in6_embedscope(&icmp6src.sin6_addr, &icmp6src, 1075 NULL, NULL)) { 1076 /* should be impossbile */ 1077 nd6log((LOG_DEBUG, 1078 "icmp6_notify_error: in6_embedscope failed\n")); 1079 goto freeit; 1080 } 1081 icmp6src.sin6_flowinfo = 1082 (eip6->ip6_flow & IPV6_FLOWLABEL_MASK); 1083 1084 if (finaldst == NULL) 1085 finaldst = &eip6->ip6_dst; 1086 ip6cp.ip6c_m = m; 1087 ip6cp.ip6c_icmp6 = icmp6; 1088 ip6cp.ip6c_ip6 = (struct ip6_hdr *)(icmp6 + 1); 1089 ip6cp.ip6c_off = eoff; 1090 ip6cp.ip6c_finaldst = finaldst; 1091 ip6cp.ip6c_src = &icmp6src; 1092 ip6cp.ip6c_nxt = nxt; 1093 1094 if (icmp6type == ICMP6_PACKET_TOO_BIG) { 1095 notifymtu = ntohl(icmp6->icmp6_mtu); 1096 ip6cp.ip6c_cmdarg = (void *)¬ifymtu; 1097 icmp6_mtudisc_update(&ip6cp, 1); /*XXX*/ 1098 } 1099 1100 ctlfunc = (void (*) (int, struct sockaddr *, void *)) 1101 (inet6sw[ip6_protox[nxt]].pr_ctlinput); 1102 if (ctlfunc) { 1103 (void) (*ctlfunc)(code, (struct sockaddr *)&icmp6dst, 1104 &ip6cp); 1105 } 1106 } 1107 return(0); 1108 1109 freeit: 1110 m_freem(m); 1111 return(-1); 1112 } 1113 1114 void 1115 icmp6_mtudisc_update(struct ip6ctlparam *ip6cp, int validated) 1116 { 1117 struct in6_addr *dst = ip6cp->ip6c_finaldst; 1118 struct icmp6_hdr *icmp6 = ip6cp->ip6c_icmp6; 1119 struct mbuf *m = ip6cp->ip6c_m; /* will be necessary for scope issue */ 1120 u_int mtu = ntohl(icmp6->icmp6_mtu); 1121 struct rtentry *rt = NULL; 1122 struct sockaddr_in6 sin6; 1123 1124 if (!validated) 1125 return; 1126 1127 bzero(&sin6, sizeof(sin6)); 1128 sin6.sin6_family = PF_INET6; 1129 sin6.sin6_len = sizeof(struct sockaddr_in6); 1130 sin6.sin6_addr = *dst; 1131 /* XXX normally, this won't happen */ 1132 if (IN6_IS_ADDR_LINKLOCAL(dst)) { 1133 sin6.sin6_addr.s6_addr16[1] = 1134 htons(m->m_pkthdr.rcvif->if_index); 1135 } 1136 /* sin6.sin6_scope_id = XXX: should be set if DST is a scoped addr */ 1137 rt = rtpurelookup((struct sockaddr *)&sin6); 1138 1139 if (rt != NULL && (rt->rt_flags & RTF_HOST) && 1140 !(rt->rt_rmx.rmx_locks & RTV_MTU)) { 1141 if (mtu < IPV6_MMTU) { /* XXX */ 1142 rt->rt_rmx.rmx_locks |= RTV_MTU; 1143 } else if (mtu < rt->rt_ifp->if_mtu && 1144 rt->rt_rmx.rmx_mtu > mtu) { 1145 icmp6stat.icp6s_pmtuchg++; 1146 rt->rt_rmx.rmx_mtu = mtu; 1147 } 1148 } 1149 if (rt) 1150 --rt->rt_refcnt; 1151 } 1152 1153 /* 1154 * Process a Node Information Query packet, based on 1155 * draft-ietf-ipngwg-icmp-name-lookups-07. 1156 * 1157 * Spec incompatibilities: 1158 * - IPv6 Subject address handling 1159 * - IPv4 Subject address handling support missing 1160 * - Proxy reply (answer even if it's not for me) 1161 * - joins NI group address at in6_ifattach() time only, does not cope 1162 * with hostname changes by sethostname(3) 1163 */ 1164 #define hostnamelen strlen(hostname) 1165 static struct mbuf * 1166 ni6_input(struct mbuf *m, int off) 1167 { 1168 struct icmp6_nodeinfo *ni6, *nni6; 1169 struct mbuf *n = NULL; 1170 u_int16_t qtype; 1171 int subjlen; 1172 int replylen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo); 1173 struct ni_reply_fqdn *fqdn; 1174 int addrs; /* for NI_QTYPE_NODEADDR */ 1175 struct ifnet *ifp = NULL; /* for NI_QTYPE_NODEADDR */ 1176 struct sockaddr_in6 sin6; /* double meaning; ip6_dst and subjectaddr */ 1177 struct sockaddr_in6 sin6_d; /* XXX: we should retrieve this from m_aux */ 1178 struct ip6_hdr *ip6; 1179 int oldfqdn = 0; /* if 1, return pascal string (03 draft) */ 1180 char *subj = NULL; 1181 struct in6_ifaddr *ia6 = NULL; 1182 1183 ip6 = mtod(m, struct ip6_hdr *); 1184 #ifndef PULLDOWN_TEST 1185 ni6 = (struct icmp6_nodeinfo *)(mtod(m, caddr_t) + off); 1186 #else 1187 IP6_EXTHDR_GET(ni6, struct icmp6_nodeinfo *, m, off, sizeof(*ni6)); 1188 if (ni6 == NULL) { 1189 /* m is already reclaimed */ 1190 return NULL; 1191 } 1192 #endif 1193 1194 /* 1195 * Validate IPv6 destination address. 1196 * 1197 * The Responder must discard the Query without further processing 1198 * unless it is one of the Responder's unicast or anycast addresses, or 1199 * a link-local scope multicast address which the Responder has joined. 1200 * [icmp-name-lookups-07, Section 4.] 1201 */ 1202 bzero(&sin6, sizeof(sin6)); 1203 sin6.sin6_family = AF_INET6; 1204 sin6.sin6_len = sizeof(struct sockaddr_in6); 1205 bcopy(&ip6->ip6_dst, &sin6.sin6_addr, sizeof(sin6.sin6_addr)); 1206 /* XXX scopeid */ 1207 if ((ia6 = (struct in6_ifaddr *)ifa_ifwithaddr((struct sockaddr *)&sin6)) != NULL) { 1208 /* unicast/anycast, fine */ 1209 if ((ia6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 1210 (icmp6_nodeinfo & 4) == 0) { 1211 nd6log((LOG_DEBUG, "ni6_input: ignore node info to " 1212 "a temporary address in %s:%d", 1213 __FILE__, __LINE__)); 1214 goto bad; 1215 } 1216 } else if (IN6_IS_ADDR_MC_LINKLOCAL(&sin6.sin6_addr)) 1217 ; /* link-local multicast, fine */ 1218 else 1219 goto bad; 1220 1221 /* validate query Subject field. */ 1222 qtype = ntohs(ni6->ni_qtype); 1223 subjlen = m->m_pkthdr.len - off - sizeof(struct icmp6_nodeinfo); 1224 switch (qtype) { 1225 case NI_QTYPE_NOOP: 1226 case NI_QTYPE_SUPTYPES: 1227 /* 07 draft */ 1228 if (ni6->ni_code == ICMP6_NI_SUBJ_FQDN && subjlen == 0) 1229 break; 1230 /* FALLTHROUGH */ 1231 case NI_QTYPE_FQDN: 1232 case NI_QTYPE_NODEADDR: 1233 switch (ni6->ni_code) { 1234 case ICMP6_NI_SUBJ_IPV6: 1235 #if ICMP6_NI_SUBJ_IPV6 != 0 1236 case 0: 1237 #endif 1238 /* 1239 * backward compatibility - try to accept 03 draft 1240 * format, where no Subject is present. 1241 */ 1242 if (qtype == NI_QTYPE_FQDN && ni6->ni_code == 0 && 1243 subjlen == 0) { 1244 oldfqdn++; 1245 break; 1246 } 1247 #if ICMP6_NI_SUBJ_IPV6 != 0 1248 if (ni6->ni_code != ICMP6_NI_SUBJ_IPV6) 1249 goto bad; 1250 #endif 1251 1252 if (subjlen != sizeof(sin6.sin6_addr)) 1253 goto bad; 1254 1255 /* 1256 * Validate Subject address. 1257 * 1258 * Not sure what exactly "address belongs to the node" 1259 * means in the spec, is it just unicast, or what? 1260 * 1261 * At this moment we consider Subject address as 1262 * "belong to the node" if the Subject address equals 1263 * to the IPv6 destination address; validation for 1264 * IPv6 destination address should have done enough 1265 * check for us. 1266 * 1267 * We do not do proxy at this moment. 1268 */ 1269 /* m_pulldown instead of copy? */ 1270 m_copydata(m, off + sizeof(struct icmp6_nodeinfo), 1271 subjlen, (caddr_t)&sin6.sin6_addr); 1272 sin6.sin6_scope_id = in6_addr2scopeid(m->m_pkthdr.rcvif, 1273 &sin6.sin6_addr); 1274 in6_embedscope(&sin6.sin6_addr, &sin6, NULL, NULL); 1275 bzero(&sin6_d, sizeof(sin6_d)); 1276 sin6_d.sin6_family = AF_INET6; /* not used, actually */ 1277 sin6_d.sin6_len = sizeof(sin6_d); /* ditto */ 1278 sin6_d.sin6_addr = ip6->ip6_dst; 1279 sin6_d.sin6_scope_id = in6_addr2scopeid(m->m_pkthdr.rcvif, 1280 &ip6->ip6_dst); 1281 in6_embedscope(&sin6_d.sin6_addr, &sin6_d, NULL, NULL); 1282 subj = (char *)&sin6; 1283 if (SA6_ARE_ADDR_EQUAL(&sin6, &sin6_d)) 1284 break; 1285 1286 /* 1287 * XXX if we are to allow other cases, we should really 1288 * be careful about scope here. 1289 * basically, we should disallow queries toward IPv6 1290 * destination X with subject Y, if scope(X) > scope(Y). 1291 * if we allow scope(X) > scope(Y), it will result in 1292 * information leakage across scope boundary. 1293 */ 1294 goto bad; 1295 1296 case ICMP6_NI_SUBJ_FQDN: 1297 /* 1298 * Validate Subject name with gethostname(3). 1299 * 1300 * The behavior may need some debate, since: 1301 * - we are not sure if the node has FQDN as 1302 * hostname (returned by gethostname(3)). 1303 * - the code does wildcard match for truncated names. 1304 * however, we are not sure if we want to perform 1305 * wildcard match, if gethostname(3) side has 1306 * truncated hostname. 1307 */ 1308 n = ni6_nametodns(hostname, hostnamelen, 0); 1309 if (!n || n->m_next || n->m_len == 0) 1310 goto bad; 1311 IP6_EXTHDR_GET(subj, char *, m, 1312 off + sizeof(struct icmp6_nodeinfo), subjlen); 1313 if (subj == NULL) 1314 goto bad; 1315 if (!ni6_dnsmatch(subj, subjlen, mtod(n, const char *), 1316 n->m_len)) { 1317 goto bad; 1318 } 1319 m_freem(n); 1320 n = NULL; 1321 break; 1322 1323 case ICMP6_NI_SUBJ_IPV4: /* XXX: to be implemented? */ 1324 default: 1325 goto bad; 1326 } 1327 break; 1328 } 1329 1330 /* refuse based on configuration. XXX ICMP6_NI_REFUSED? */ 1331 switch (qtype) { 1332 case NI_QTYPE_FQDN: 1333 if ((icmp6_nodeinfo & 1) == 0) 1334 goto bad; 1335 break; 1336 case NI_QTYPE_NODEADDR: 1337 if ((icmp6_nodeinfo & 2) == 0) 1338 goto bad; 1339 break; 1340 } 1341 1342 /* guess reply length */ 1343 switch (qtype) { 1344 case NI_QTYPE_NOOP: 1345 break; /* no reply data */ 1346 case NI_QTYPE_SUPTYPES: 1347 replylen += sizeof(u_int32_t); 1348 break; 1349 case NI_QTYPE_FQDN: 1350 /* XXX will append an mbuf */ 1351 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1352 break; 1353 case NI_QTYPE_NODEADDR: 1354 addrs = ni6_addrs(ni6, m, &ifp, subj); 1355 if ((replylen += addrs * (sizeof(struct in6_addr) + 1356 sizeof(u_int32_t))) > MCLBYTES) 1357 replylen = MCLBYTES; /* XXX: will truncate pkt later */ 1358 break; 1359 default: 1360 /* 1361 * XXX: We must return a reply with the ICMP6 code 1362 * `unknown Qtype' in this case. However we regard the case 1363 * as an FQDN query for backward compatibility. 1364 * Older versions set a random value to this field, 1365 * so it rarely varies in the defined qtypes. 1366 * But the mechanism is not reliable... 1367 * maybe we should obsolete older versions. 1368 */ 1369 qtype = NI_QTYPE_FQDN; 1370 /* XXX will append an mbuf */ 1371 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1372 oldfqdn++; 1373 break; 1374 } 1375 1376 /* allocate an mbuf to reply. */ 1377 MGETHDR(n, MB_DONTWAIT, m->m_type); 1378 if (n == NULL) { 1379 m_freem(m); 1380 return(NULL); 1381 } 1382 M_MOVE_PKTHDR(n, m); /* just for recvif */ 1383 if (replylen > MHLEN) { 1384 if (replylen > MCLBYTES) { 1385 /* 1386 * XXX: should we try to allocate more? But MCLBYTES 1387 * is probably much larger than IPV6_MMTU... 1388 */ 1389 goto bad; 1390 } 1391 MCLGET(n, MB_DONTWAIT); 1392 if ((n->m_flags & M_EXT) == 0) { 1393 goto bad; 1394 } 1395 } 1396 n->m_pkthdr.len = n->m_len = replylen; 1397 1398 /* copy mbuf header and IPv6 + Node Information base headers */ 1399 bcopy(mtod(m, caddr_t), mtod(n, caddr_t), sizeof(struct ip6_hdr)); 1400 nni6 = (struct icmp6_nodeinfo *)(mtod(n, struct ip6_hdr *) + 1); 1401 bcopy((caddr_t)ni6, (caddr_t)nni6, sizeof(struct icmp6_nodeinfo)); 1402 1403 /* qtype dependent procedure */ 1404 switch (qtype) { 1405 case NI_QTYPE_NOOP: 1406 nni6->ni_code = ICMP6_NI_SUCCESS; 1407 nni6->ni_flags = 0; 1408 break; 1409 case NI_QTYPE_SUPTYPES: 1410 { 1411 u_int32_t v; 1412 nni6->ni_code = ICMP6_NI_SUCCESS; 1413 nni6->ni_flags = htons(0x0000); /* raw bitmap */ 1414 /* supports NOOP, SUPTYPES, FQDN, and NODEADDR */ 1415 v = (u_int32_t)htonl(0x0000000f); 1416 bcopy(&v, nni6 + 1, sizeof(u_int32_t)); 1417 break; 1418 } 1419 case NI_QTYPE_FQDN: 1420 nni6->ni_code = ICMP6_NI_SUCCESS; 1421 fqdn = (struct ni_reply_fqdn *)(mtod(n, caddr_t) + 1422 sizeof(struct ip6_hdr) + 1423 sizeof(struct icmp6_nodeinfo)); 1424 nni6->ni_flags = 0; /* XXX: meaningless TTL */ 1425 fqdn->ni_fqdn_ttl = 0; /* ditto. */ 1426 /* 1427 * XXX do we really have FQDN in variable "hostname"? 1428 */ 1429 n->m_next = ni6_nametodns(hostname, hostnamelen, oldfqdn); 1430 if (n->m_next == NULL) 1431 goto bad; 1432 /* XXX we assume that n->m_next is not a chain */ 1433 if (n->m_next->m_next != NULL) 1434 goto bad; 1435 n->m_pkthdr.len += n->m_next->m_len; 1436 break; 1437 case NI_QTYPE_NODEADDR: 1438 { 1439 int lenlim, copied; 1440 1441 nni6->ni_code = ICMP6_NI_SUCCESS; 1442 n->m_pkthdr.len = n->m_len = 1443 sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo); 1444 lenlim = M_TRAILINGSPACE(n); 1445 copied = ni6_store_addrs(ni6, nni6, ifp, lenlim); 1446 /* XXX: reset mbuf length */ 1447 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) + 1448 sizeof(struct icmp6_nodeinfo) + copied; 1449 break; 1450 } 1451 default: 1452 break; /* XXX impossible! */ 1453 } 1454 1455 nni6->ni_type = ICMP6_NI_REPLY; 1456 m_freem(m); 1457 return(n); 1458 1459 bad: 1460 m_freem(m); 1461 if (n) 1462 m_freem(n); 1463 return(NULL); 1464 } 1465 #undef hostnamelen 1466 1467 /* 1468 * make a mbuf with DNS-encoded string. no compression support. 1469 * 1470 * XXX names with less than 2 dots (like "foo" or "foo.section") will be 1471 * treated as truncated name (two \0 at the end). this is a wild guess. 1472 */ 1473 static struct mbuf * 1474 ni6_nametodns(const char *name, int namelen, 1475 int old) /* return pascal string if non-zero */ 1476 { 1477 struct mbuf *m; 1478 char *cp, *ep; 1479 const char *p, *q; 1480 int i, len, nterm; 1481 1482 if (old) 1483 len = namelen + 1; 1484 else 1485 len = MCLBYTES; 1486 1487 /* because MAXHOSTNAMELEN is usually 256, we use cluster mbuf */ 1488 MGET(m, MB_DONTWAIT, MT_DATA); 1489 if (m && len > MLEN) { 1490 MCLGET(m, MB_DONTWAIT); 1491 if ((m->m_flags & M_EXT) == 0) 1492 goto fail; 1493 } 1494 if (!m) 1495 goto fail; 1496 m->m_next = NULL; 1497 1498 if (old) { 1499 m->m_len = len; 1500 *mtod(m, char *) = namelen; 1501 bcopy(name, mtod(m, char *) + 1, namelen); 1502 return m; 1503 } else { 1504 m->m_len = 0; 1505 cp = mtod(m, char *); 1506 ep = mtod(m, char *) + M_TRAILINGSPACE(m); 1507 1508 /* if not certain about my name, return empty buffer */ 1509 if (namelen == 0) 1510 return m; 1511 1512 /* 1513 * guess if it looks like shortened hostname, or FQDN. 1514 * shortened hostname needs two trailing "\0". 1515 */ 1516 i = 0; 1517 for (p = name; p < name + namelen; p++) { 1518 if (*p && *p == '.') 1519 i++; 1520 } 1521 if (i < 2) 1522 nterm = 2; 1523 else 1524 nterm = 1; 1525 1526 p = name; 1527 while (cp < ep && p < name + namelen) { 1528 i = 0; 1529 for (q = p; q < name + namelen && *q && *q != '.'; q++) 1530 i++; 1531 /* result does not fit into mbuf */ 1532 if (cp + i + 1 >= ep) 1533 goto fail; 1534 /* 1535 * DNS label length restriction, RFC1035 page 8. 1536 * "i == 0" case is included here to avoid returning 1537 * 0-length label on "foo..bar". 1538 */ 1539 if (i <= 0 || i >= 64) 1540 goto fail; 1541 *cp++ = i; 1542 bcopy(p, cp, i); 1543 cp += i; 1544 p = q; 1545 if (p < name + namelen && *p == '.') 1546 p++; 1547 } 1548 /* termination */ 1549 if (cp + nterm >= ep) 1550 goto fail; 1551 while (nterm-- > 0) 1552 *cp++ = '\0'; 1553 m->m_len = cp - mtod(m, char *); 1554 return m; 1555 } 1556 1557 panic("should not reach here"); 1558 /* NOTREACHED */ 1559 1560 fail: 1561 if (m) 1562 m_freem(m); 1563 return NULL; 1564 } 1565 1566 /* 1567 * check if two DNS-encoded string matches. takes care of truncated 1568 * form (with \0\0 at the end). no compression support. 1569 * XXX upper/lowercase match (see RFC2065) 1570 */ 1571 static int 1572 ni6_dnsmatch(const char *a, int alen, const char *b, int blen) 1573 { 1574 const char *a0, *b0; 1575 int l; 1576 1577 /* simplest case - need validation? */ 1578 if (alen == blen && bcmp(a, b, alen) == 0) 1579 return 1; 1580 1581 a0 = a; 1582 b0 = b; 1583 1584 /* termination is mandatory */ 1585 if (alen < 2 || blen < 2) 1586 return 0; 1587 if (a0[alen - 1] != '\0' || b0[blen - 1] != '\0') 1588 return 0; 1589 alen--; 1590 blen--; 1591 1592 while (a - a0 < alen && b - b0 < blen) { 1593 if (a - a0 + 1 > alen || b - b0 + 1 > blen) 1594 return 0; 1595 1596 if ((signed char)a[0] < 0 || (signed char)b[0] < 0) 1597 return 0; 1598 /* we don't support compression yet */ 1599 if (a[0] >= 64 || b[0] >= 64) 1600 return 0; 1601 1602 /* truncated case */ 1603 if (a[0] == 0 && a - a0 == alen - 1) 1604 return 1; 1605 if (b[0] == 0 && b - b0 == blen - 1) 1606 return 1; 1607 if (a[0] == 0 || b[0] == 0) 1608 return 0; 1609 1610 if (a[0] != b[0]) 1611 return 0; 1612 l = a[0]; 1613 if (a - a0 + 1 + l > alen || b - b0 + 1 + l > blen) 1614 return 0; 1615 if (bcmp(a + 1, b + 1, l) != 0) 1616 return 0; 1617 1618 a += 1 + l; 1619 b += 1 + l; 1620 } 1621 1622 if (a - a0 == alen && b - b0 == blen) 1623 return 1; 1624 else 1625 return 0; 1626 } 1627 1628 /* 1629 * calculate the number of addresses to be returned in the node info reply. 1630 */ 1631 static int 1632 ni6_addrs(struct icmp6_nodeinfo *ni6, struct mbuf *m, struct ifnet **ifpp, 1633 char *subj) 1634 { 1635 struct ifnet *ifp; 1636 struct in6_ifaddr *ifa6; 1637 struct ifaddr *ifa; 1638 struct sockaddr_in6 *subj_ip6 = NULL; /* XXX pedant */ 1639 int addrs = 0, addrsofif, iffound = 0; 1640 int niflags = ni6->ni_flags; 1641 1642 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0) { 1643 switch (ni6->ni_code) { 1644 case ICMP6_NI_SUBJ_IPV6: 1645 if (subj == NULL) /* must be impossible... */ 1646 return(0); 1647 subj_ip6 = (struct sockaddr_in6 *)subj; 1648 break; 1649 default: 1650 /* 1651 * XXX: we only support IPv6 subject address for 1652 * this Qtype. 1653 */ 1654 return(0); 1655 } 1656 } 1657 1658 for (ifp = TAILQ_FIRST(&ifnet); ifp; ifp = TAILQ_NEXT(ifp, if_list)) 1659 { 1660 addrsofif = 0; 1661 TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list) 1662 { 1663 if (ifa->ifa_addr->sa_family != AF_INET6) 1664 continue; 1665 ifa6 = (struct in6_ifaddr *)ifa; 1666 1667 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0 && 1668 IN6_ARE_ADDR_EQUAL(&subj_ip6->sin6_addr, 1669 &ifa6->ia_addr.sin6_addr)) 1670 iffound = 1; 1671 1672 /* 1673 * IPv4-mapped addresses can only be returned by a 1674 * Node Information proxy, since they represent 1675 * addresses of IPv4-only nodes, which perforce do 1676 * not implement this protocol. 1677 * [icmp-name-lookups-07, Section 5.4] 1678 * So we don't support NI_NODEADDR_FLAG_COMPAT in 1679 * this function at this moment. 1680 */ 1681 1682 /* What do we have to do about ::1? */ 1683 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1684 case IPV6_ADDR_SCOPE_LINKLOCAL: 1685 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0) 1686 continue; 1687 break; 1688 case IPV6_ADDR_SCOPE_SITELOCAL: 1689 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0) 1690 continue; 1691 break; 1692 case IPV6_ADDR_SCOPE_GLOBAL: 1693 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0) 1694 continue; 1695 break; 1696 default: 1697 continue; 1698 } 1699 1700 /* 1701 * check if anycast is okay. 1702 * XXX: just experimental. not in the spec. 1703 */ 1704 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 && 1705 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0) 1706 continue; /* we need only unicast addresses */ 1707 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 1708 (icmp6_nodeinfo & 4) == 0) { 1709 continue; 1710 } 1711 addrsofif++; /* count the address */ 1712 } 1713 if (iffound) { 1714 *ifpp = ifp; 1715 return(addrsofif); 1716 } 1717 1718 addrs += addrsofif; 1719 } 1720 1721 return(addrs); 1722 } 1723 1724 static int 1725 ni6_store_addrs(struct icmp6_nodeinfo *ni6, struct icmp6_nodeinfo *nni6, 1726 struct ifnet *ifp0, int resid) 1727 { 1728 struct ifnet *ifp = ifp0 ? ifp0 : TAILQ_FIRST(&ifnet); 1729 struct in6_ifaddr *ifa6; 1730 struct ifaddr *ifa; 1731 struct ifnet *ifp_dep = NULL; 1732 int copied = 0, allow_deprecated = 0; 1733 u_char *cp = (u_char *)(nni6 + 1); 1734 int niflags = ni6->ni_flags; 1735 u_int32_t ltime; 1736 1737 if (ifp0 == NULL && !(niflags & NI_NODEADDR_FLAG_ALL)) 1738 return(0); /* needless to copy */ 1739 1740 again: 1741 1742 for (; ifp; ifp = TAILQ_NEXT(ifp, if_list)) 1743 { 1744 TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list) { 1745 if (ifa->ifa_addr->sa_family != AF_INET6) 1746 continue; 1747 ifa6 = (struct in6_ifaddr *)ifa; 1748 1749 if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) != 0 && 1750 allow_deprecated == 0) { 1751 /* 1752 * prefererred address should be put before 1753 * deprecated addresses. 1754 */ 1755 1756 /* record the interface for later search */ 1757 if (ifp_dep == NULL) 1758 ifp_dep = ifp; 1759 1760 continue; 1761 } 1762 else if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) == 0 && 1763 allow_deprecated != 0) 1764 continue; /* we now collect deprecated addrs */ 1765 1766 /* What do we have to do about ::1? */ 1767 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1768 case IPV6_ADDR_SCOPE_LINKLOCAL: 1769 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0) 1770 continue; 1771 break; 1772 case IPV6_ADDR_SCOPE_SITELOCAL: 1773 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0) 1774 continue; 1775 break; 1776 case IPV6_ADDR_SCOPE_GLOBAL: 1777 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0) 1778 continue; 1779 break; 1780 default: 1781 continue; 1782 } 1783 1784 /* 1785 * check if anycast is okay. 1786 * XXX: just experimental. not in the spec. 1787 */ 1788 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 && 1789 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0) 1790 continue; 1791 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 1792 (icmp6_nodeinfo & 4) == 0) { 1793 continue; 1794 } 1795 1796 /* now we can copy the address */ 1797 if (resid < sizeof(struct in6_addr) + 1798 sizeof(u_int32_t)) { 1799 /* 1800 * We give up much more copy. 1801 * Set the truncate flag and return. 1802 */ 1803 nni6->ni_flags |= 1804 NI_NODEADDR_FLAG_TRUNCATE; 1805 return(copied); 1806 } 1807 1808 /* 1809 * Set the TTL of the address. 1810 * The TTL value should be one of the following 1811 * according to the specification: 1812 * 1813 * 1. The remaining lifetime of a DHCP lease on the 1814 * address, or 1815 * 2. The remaining Valid Lifetime of a prefix from 1816 * which the address was derived through Stateless 1817 * Autoconfiguration. 1818 * 1819 * Note that we currently do not support stateful 1820 * address configuration by DHCPv6, so the former 1821 * case can't happen. 1822 */ 1823 if (ifa6->ia6_lifetime.ia6t_expire == 0) 1824 ltime = ND6_INFINITE_LIFETIME; 1825 else { 1826 if (ifa6->ia6_lifetime.ia6t_expire > 1827 time_second) 1828 ltime = htonl(ifa6->ia6_lifetime.ia6t_expire - time_second); 1829 else 1830 ltime = 0; 1831 } 1832 1833 bcopy(<ime, cp, sizeof(u_int32_t)); 1834 cp += sizeof(u_int32_t); 1835 1836 /* copy the address itself */ 1837 bcopy(&ifa6->ia_addr.sin6_addr, cp, 1838 sizeof(struct in6_addr)); 1839 /* XXX: KAME link-local hack; remove ifindex */ 1840 if (IN6_IS_ADDR_LINKLOCAL(&ifa6->ia_addr.sin6_addr)) 1841 ((struct in6_addr *)cp)->s6_addr16[1] = 0; 1842 cp += sizeof(struct in6_addr); 1843 1844 resid -= (sizeof(struct in6_addr) + sizeof(u_int32_t)); 1845 copied += (sizeof(struct in6_addr) + 1846 sizeof(u_int32_t)); 1847 } 1848 if (ifp0) /* we need search only on the specified IF */ 1849 break; 1850 } 1851 1852 if (allow_deprecated == 0 && ifp_dep != NULL) { 1853 ifp = ifp_dep; 1854 allow_deprecated = 1; 1855 1856 goto again; 1857 } 1858 1859 return(copied); 1860 } 1861 1862 /* 1863 * XXX almost dup'ed code with rip6_input. 1864 */ 1865 static int 1866 icmp6_rip6_input(struct mbuf **mp, int off) 1867 { 1868 struct mbuf *m = *mp; 1869 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1870 struct in6pcb *in6p; 1871 struct in6pcb *last = NULL; 1872 struct sockaddr_in6 rip6src; 1873 struct icmp6_hdr *icmp6; 1874 struct mbuf *opts = NULL; 1875 1876 #ifndef PULLDOWN_TEST 1877 /* this is assumed to be safe. */ 1878 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off); 1879 #else 1880 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 1881 if (icmp6 == NULL) { 1882 /* m is already reclaimed */ 1883 return IPPROTO_DONE; 1884 } 1885 #endif 1886 1887 bzero(&rip6src, sizeof(rip6src)); 1888 rip6src.sin6_len = sizeof(struct sockaddr_in6); 1889 rip6src.sin6_family = AF_INET6; 1890 /* KAME hack: recover scopeid */ 1891 (void)in6_recoverscope(&rip6src, &ip6->ip6_src, m->m_pkthdr.rcvif); 1892 1893 LIST_FOREACH(in6p, &ripcbinfo.pcblisthead, inp_list) 1894 { 1895 if (in6p->inp_flags & INP_PLACEMARKER) 1896 continue; 1897 if ((in6p->inp_vflag & INP_IPV6) == 0) 1898 continue; 1899 #ifdef HAVE_NRL_INPCB 1900 if (!(in6p->in6p_flags & INP_IPV6)) 1901 continue; 1902 #endif 1903 if (in6p->in6p_ip6_nxt != IPPROTO_ICMPV6) 1904 continue; 1905 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr) && 1906 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr, &ip6->ip6_dst)) 1907 continue; 1908 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr) && 1909 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr, &ip6->ip6_src)) 1910 continue; 1911 if (in6p->in6p_icmp6filt 1912 && ICMP6_FILTER_WILLBLOCK(icmp6->icmp6_type, 1913 in6p->in6p_icmp6filt)) 1914 continue; 1915 if (last) { 1916 struct mbuf *n; 1917 if ((n = m_copy(m, 0, (int)M_COPYALL)) != NULL) { 1918 if (last->in6p_flags & IN6P_CONTROLOPTS) 1919 ip6_savecontrol(last, &opts, ip6, n); 1920 /* strip intermediate headers */ 1921 m_adj(n, off); 1922 if (sbappendaddr(&last->in6p_socket->so_rcv, 1923 (struct sockaddr *)&rip6src, 1924 n, opts) == 0) { 1925 /* should notify about lost packet */ 1926 m_freem(n); 1927 if (opts) { 1928 m_freem(opts); 1929 } 1930 } else 1931 sorwakeup(last->in6p_socket); 1932 opts = NULL; 1933 } 1934 } 1935 last = in6p; 1936 } 1937 if (last) { 1938 if (last->in6p_flags & IN6P_CONTROLOPTS) 1939 ip6_savecontrol(last, &opts, ip6, m); 1940 /* strip intermediate headers */ 1941 m_adj(m, off); 1942 if (sbappendaddr(&last->in6p_socket->so_rcv, 1943 (struct sockaddr *)&rip6src, m, opts) == 0) { 1944 m_freem(m); 1945 if (opts) 1946 m_freem(opts); 1947 } else 1948 sorwakeup(last->in6p_socket); 1949 } else { 1950 m_freem(m); 1951 ip6stat.ip6s_delivered--; 1952 } 1953 return IPPROTO_DONE; 1954 } 1955 1956 /* 1957 * Reflect the ip6 packet back to the source. 1958 * OFF points to the icmp6 header, counted from the top of the mbuf. 1959 */ 1960 void 1961 icmp6_reflect(struct mbuf *m, size_t off) 1962 { 1963 struct ip6_hdr *ip6; 1964 struct icmp6_hdr *icmp6; 1965 struct in6_ifaddr *ia; 1966 struct in6_addr t, *src = 0; 1967 int plen; 1968 int type, code; 1969 struct ifnet *outif = NULL; 1970 struct sockaddr_in6 sa6_src, sa6_dst; 1971 #ifdef COMPAT_RFC1885 1972 int mtu = IPV6_MMTU; 1973 struct sockaddr_in6 *sin6 = &icmp6_reflect_rt.ro_dst; 1974 #endif 1975 1976 /* too short to reflect */ 1977 if (off < sizeof(struct ip6_hdr)) { 1978 nd6log((LOG_DEBUG, 1979 "sanity fail: off=%lx, sizeof(ip6)=%lx in %s:%d\n", 1980 (u_long)off, (u_long)sizeof(struct ip6_hdr), 1981 __FILE__, __LINE__)); 1982 goto bad; 1983 } 1984 1985 /* 1986 * If there are extra headers between IPv6 and ICMPv6, strip 1987 * off that header first. 1988 */ 1989 #ifdef DIAGNOSTIC 1990 if (sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) > MHLEN) 1991 panic("assumption failed in icmp6_reflect"); 1992 #endif 1993 if (off > sizeof(struct ip6_hdr)) { 1994 size_t l; 1995 struct ip6_hdr nip6; 1996 1997 l = off - sizeof(struct ip6_hdr); 1998 m_copydata(m, 0, sizeof(nip6), (caddr_t)&nip6); 1999 m_adj(m, l); 2000 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 2001 if (m->m_len < l) { 2002 if ((m = m_pullup(m, l)) == NULL) 2003 return; 2004 } 2005 bcopy((caddr_t)&nip6, mtod(m, caddr_t), sizeof(nip6)); 2006 } else /* off == sizeof(struct ip6_hdr) */ { 2007 size_t l; 2008 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 2009 if (m->m_len < l) { 2010 if ((m = m_pullup(m, l)) == NULL) 2011 return; 2012 } 2013 } 2014 plen = m->m_pkthdr.len - sizeof(struct ip6_hdr); 2015 ip6 = mtod(m, struct ip6_hdr *); 2016 ip6->ip6_nxt = IPPROTO_ICMPV6; 2017 icmp6 = (struct icmp6_hdr *)(ip6 + 1); 2018 type = icmp6->icmp6_type; /* keep type for statistics */ 2019 code = icmp6->icmp6_code; /* ditto. */ 2020 2021 t = ip6->ip6_dst; 2022 /* 2023 * ip6_input() drops a packet if its src is multicast. 2024 * So, the src is never multicast. 2025 */ 2026 ip6->ip6_dst = ip6->ip6_src; 2027 2028 /* 2029 * XXX: make sure to embed scope zone information, using 2030 * already embedded IDs or the received interface (if any). 2031 * Note that rcvif may be NULL. 2032 * TODO: scoped routing case (XXX). 2033 */ 2034 bzero(&sa6_src, sizeof(sa6_src)); 2035 sa6_src.sin6_family = AF_INET6; 2036 sa6_src.sin6_len = sizeof(sa6_src); 2037 sa6_src.sin6_addr = ip6->ip6_dst; 2038 in6_recoverscope(&sa6_src, &ip6->ip6_dst, m->m_pkthdr.rcvif); 2039 in6_embedscope(&ip6->ip6_dst, &sa6_src, NULL, NULL); 2040 bzero(&sa6_dst, sizeof(sa6_dst)); 2041 sa6_dst.sin6_family = AF_INET6; 2042 sa6_dst.sin6_len = sizeof(sa6_dst); 2043 sa6_dst.sin6_addr = t; 2044 in6_recoverscope(&sa6_dst, &t, m->m_pkthdr.rcvif); 2045 in6_embedscope(&t, &sa6_dst, NULL, NULL); 2046 2047 #ifdef COMPAT_RFC1885 2048 /* 2049 * xxx guess MTU 2050 * RFC 1885 requires that echo reply should be truncated if it 2051 * does not fit in with (return) path MTU, but the description was 2052 * removed in the new spec. 2053 */ 2054 if (icmp6_reflect_rt.ro_rt == 0 || 2055 ! (IN6_ARE_ADDR_EQUAL(&sin6->sin6_addr, &ip6->ip6_dst))) { 2056 if (icmp6_reflect_rt.ro_rt) { 2057 RTFREE(icmp6_reflect_rt.ro_rt); 2058 icmp6_reflect_rt.ro_rt = 0; 2059 } 2060 bzero(sin6, sizeof(*sin6)); 2061 sin6->sin6_family = PF_INET6; 2062 sin6->sin6_len = sizeof(struct sockaddr_in6); 2063 sin6->sin6_addr = ip6->ip6_dst; 2064 2065 rtalloc_ign((struct route *)&icmp6_reflect_rt.ro_rt, 2066 RTF_PRCLONING); 2067 } 2068 2069 if (icmp6_reflect_rt.ro_rt == 0) 2070 goto bad; 2071 2072 if ((icmp6_reflect_rt.ro_rt->rt_flags & RTF_HOST) 2073 && mtu < icmp6_reflect_rt.ro_rt->rt_ifp->if_mtu) 2074 mtu = icmp6_reflect_rt.ro_rt->rt_rmx.rmx_mtu; 2075 2076 if (mtu < m->m_pkthdr.len) { 2077 plen -= (m->m_pkthdr.len - mtu); 2078 m_adj(m, mtu - m->m_pkthdr.len); 2079 } 2080 #endif 2081 /* 2082 * If the incoming packet was addressed directly to us(i.e. unicast), 2083 * use dst as the src for the reply. 2084 * The IN6_IFF_NOTREADY case would be VERY rare, but is possible 2085 * (for example) when we encounter an error while forwarding procedure 2086 * destined to a duplicated address of ours. 2087 */ 2088 for (ia = in6_ifaddr; ia; ia = ia->ia_next) 2089 if (IN6_ARE_ADDR_EQUAL(&t, &ia->ia_addr.sin6_addr) && 2090 (ia->ia6_flags & (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY)) == 0) { 2091 src = &t; 2092 break; 2093 } 2094 if (ia == NULL && IN6_IS_ADDR_LINKLOCAL(&t) && (m->m_flags & M_LOOP)) { 2095 /* 2096 * This is the case if the dst is our link-local address 2097 * and the sender is also ourselves. 2098 */ 2099 src = &t; 2100 } 2101 2102 if (src == 0) { 2103 int e; 2104 struct route_in6 ro; 2105 2106 /* 2107 * This case matches to multicasts, our anycast, or unicasts 2108 * that we do not own. Select a source address based on the 2109 * source address of the erroneous packet. 2110 */ 2111 bzero(&ro, sizeof(ro)); 2112 src = in6_selectsrc(&sa6_src, NULL, NULL, &ro, NULL, &e); 2113 if (ro.ro_rt) 2114 RTFREE(ro.ro_rt); /* XXX: we could use this */ 2115 if (src == NULL) { 2116 nd6log((LOG_DEBUG, 2117 "icmp6_reflect: source can't be determined: " 2118 "dst=%s, error=%d\n", 2119 ip6_sprintf(&sa6_src.sin6_addr), e)); 2120 goto bad; 2121 } 2122 } 2123 2124 ip6->ip6_src = *src; 2125 2126 ip6->ip6_flow = 0; 2127 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2128 ip6->ip6_vfc |= IPV6_VERSION; 2129 ip6->ip6_nxt = IPPROTO_ICMPV6; 2130 if (m->m_pkthdr.rcvif) { 2131 /* XXX: This may not be the outgoing interface */ 2132 ip6->ip6_hlim = ND_IFINFO(m->m_pkthdr.rcvif)->chlim; 2133 } else 2134 ip6->ip6_hlim = ip6_defhlim; 2135 2136 icmp6->icmp6_cksum = 0; 2137 icmp6->icmp6_cksum = in6_cksum(m, IPPROTO_ICMPV6, 2138 sizeof(struct ip6_hdr), plen); 2139 2140 /* 2141 * XXX option handling 2142 */ 2143 2144 m->m_flags &= ~(M_BCAST|M_MCAST); 2145 2146 #ifdef COMPAT_RFC1885 2147 ip6_output(m, NULL, &icmp6_reflect_rt, 0, NULL, &outif, NULL); 2148 #else 2149 ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL); 2150 #endif 2151 if (outif) 2152 icmp6_ifoutstat_inc(outif, type, code); 2153 2154 return; 2155 2156 bad: 2157 m_freem(m); 2158 return; 2159 } 2160 2161 void 2162 icmp6_fasttimo(void) 2163 { 2164 2165 mld6_fasttimeo(); 2166 } 2167 2168 static const char * 2169 icmp6_redirect_diag(struct in6_addr *src6, struct in6_addr *dst6, 2170 struct in6_addr *tgt6) 2171 { 2172 static char buf[1024]; 2173 snprintf(buf, sizeof(buf), "(src=%s dst=%s tgt=%s)", 2174 ip6_sprintf(src6), ip6_sprintf(dst6), ip6_sprintf(tgt6)); 2175 return buf; 2176 } 2177 2178 void 2179 icmp6_redirect_input(struct mbuf *m, int off) 2180 { 2181 struct ifnet *ifp = m->m_pkthdr.rcvif; 2182 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 2183 struct nd_redirect *nd_rd; 2184 int icmp6len = ntohs(ip6->ip6_plen); 2185 char *lladdr = NULL; 2186 int lladdrlen = 0; 2187 u_char *redirhdr = NULL; 2188 int redirhdrlen = 0; 2189 struct rtentry *rt = NULL; 2190 int is_router; 2191 int is_onlink; 2192 struct in6_addr src6 = ip6->ip6_src; 2193 struct in6_addr redtgt6; 2194 struct in6_addr reddst6; 2195 union nd_opts ndopts; 2196 2197 if (!m || !ifp) 2198 return; 2199 2200 /* XXX if we are router, we don't update route by icmp6 redirect */ 2201 if (ip6_forwarding) 2202 goto freeit; 2203 if (!icmp6_rediraccept) 2204 goto freeit; 2205 2206 #ifndef PULLDOWN_TEST 2207 IP6_EXTHDR_CHECK(m, off, icmp6len,); 2208 nd_rd = (struct nd_redirect *)((caddr_t)ip6 + off); 2209 #else 2210 IP6_EXTHDR_GET(nd_rd, struct nd_redirect *, m, off, icmp6len); 2211 if (nd_rd == NULL) { 2212 icmp6stat.icp6s_tooshort++; 2213 return; 2214 } 2215 #endif 2216 redtgt6 = nd_rd->nd_rd_target; 2217 reddst6 = nd_rd->nd_rd_dst; 2218 2219 if (IN6_IS_ADDR_LINKLOCAL(&redtgt6)) 2220 redtgt6.s6_addr16[1] = htons(ifp->if_index); 2221 if (IN6_IS_ADDR_LINKLOCAL(&reddst6)) 2222 reddst6.s6_addr16[1] = htons(ifp->if_index); 2223 2224 /* validation */ 2225 if (!IN6_IS_ADDR_LINKLOCAL(&src6)) { 2226 nd6log((LOG_ERR, 2227 "ICMP6 redirect sent from %s rejected; " 2228 "must be from linklocal\n", ip6_sprintf(&src6))); 2229 goto bad; 2230 } 2231 if (ip6->ip6_hlim != 255) { 2232 nd6log((LOG_ERR, 2233 "ICMP6 redirect sent from %s rejected; " 2234 "hlim=%d (must be 255)\n", 2235 ip6_sprintf(&src6), ip6->ip6_hlim)); 2236 goto bad; 2237 } 2238 { 2239 /* ip6->ip6_src must be equal to gw for icmp6->icmp6_reddst */ 2240 struct sockaddr_in6 sin6; 2241 struct in6_addr *gw6; 2242 2243 bzero(&sin6, sizeof(sin6)); 2244 sin6.sin6_family = AF_INET6; 2245 sin6.sin6_len = sizeof(struct sockaddr_in6); 2246 bcopy(&reddst6, &sin6.sin6_addr, sizeof reddst6); 2247 rt = rtpurelookup((struct sockaddr *)&sin6); 2248 if (rt != NULL) { 2249 if (rt->rt_gateway == NULL || 2250 rt->rt_gateway->sa_family != AF_INET6) { 2251 nd6log((LOG_ERR, 2252 "ICMP6 redirect rejected; no route " 2253 "with inet6 gateway found for redirect dst: %s\n", 2254 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2255 --rt->rt_refcnt; 2256 goto bad; 2257 } 2258 2259 gw6 = &(((struct sockaddr_in6 *)rt->rt_gateway)->sin6_addr); 2260 if (bcmp(&src6, gw6, sizeof(struct in6_addr)) != 0) { 2261 nd6log((LOG_ERR, 2262 "ICMP6 redirect rejected; " 2263 "not equal to gw-for-src=%s (must be same): " 2264 "%s\n", 2265 ip6_sprintf(gw6), 2266 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2267 --rt->rt_refcnt; 2268 goto bad; 2269 } 2270 } else { 2271 nd6log((LOG_ERR, 2272 "ICMP6 redirect rejected; " 2273 "no route found for redirect dst: %s\n", 2274 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2275 goto bad; 2276 } 2277 --rt->rt_refcnt; 2278 rt = NULL; 2279 } 2280 if (IN6_IS_ADDR_MULTICAST(&reddst6)) { 2281 nd6log((LOG_ERR, 2282 "ICMP6 redirect rejected; " 2283 "redirect dst must be unicast: %s\n", 2284 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2285 goto bad; 2286 } 2287 2288 is_router = is_onlink = 0; 2289 if (IN6_IS_ADDR_LINKLOCAL(&redtgt6)) 2290 is_router = 1; /* router case */ 2291 if (bcmp(&redtgt6, &reddst6, sizeof(redtgt6)) == 0) 2292 is_onlink = 1; /* on-link destination case */ 2293 if (!is_router && !is_onlink) { 2294 nd6log((LOG_ERR, 2295 "ICMP6 redirect rejected; " 2296 "neither router case nor onlink case: %s\n", 2297 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2298 goto bad; 2299 } 2300 /* validation passed */ 2301 2302 icmp6len -= sizeof(*nd_rd); 2303 nd6_option_init(nd_rd + 1, icmp6len, &ndopts); 2304 if (nd6_options(&ndopts) < 0) { 2305 nd6log((LOG_INFO, "icmp6_redirect_input: " 2306 "invalid ND option, rejected: %s\n", 2307 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2308 /* nd6_options have incremented stats */ 2309 goto freeit; 2310 } 2311 2312 if (ndopts.nd_opts_tgt_lladdr) { 2313 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 2314 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 2315 } 2316 2317 if (ndopts.nd_opts_rh) { 2318 redirhdrlen = ndopts.nd_opts_rh->nd_opt_rh_len; 2319 redirhdr = (u_char *)(ndopts.nd_opts_rh + 1); /* xxx */ 2320 } 2321 2322 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 2323 nd6log((LOG_INFO, 2324 "icmp6_redirect_input: lladdrlen mismatch for %s " 2325 "(if %d, icmp6 packet %d): %s\n", 2326 ip6_sprintf(&redtgt6), ifp->if_addrlen, lladdrlen - 2, 2327 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2328 goto bad; 2329 } 2330 2331 /* RFC 2461 8.3 */ 2332 nd6_cache_lladdr(ifp, &redtgt6, lladdr, lladdrlen, ND_REDIRECT, 2333 is_onlink ? ND_REDIRECT_ONLINK : ND_REDIRECT_ROUTER); 2334 2335 if (!is_onlink) { /* better router case. perform rtredirect. */ 2336 /* perform rtredirect */ 2337 struct sockaddr_in6 sdst; 2338 struct sockaddr_in6 sgw; 2339 struct sockaddr_in6 ssrc; 2340 2341 bzero(&sdst, sizeof(sdst)); 2342 bzero(&sgw, sizeof(sgw)); 2343 bzero(&ssrc, sizeof(ssrc)); 2344 sdst.sin6_family = sgw.sin6_family = ssrc.sin6_family = AF_INET6; 2345 sdst.sin6_len = sgw.sin6_len = ssrc.sin6_len = 2346 sizeof(struct sockaddr_in6); 2347 bcopy(&redtgt6, &sgw.sin6_addr, sizeof(struct in6_addr)); 2348 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2349 bcopy(&src6, &ssrc.sin6_addr, sizeof(struct in6_addr)); 2350 rtredirect((struct sockaddr *)&sdst, (struct sockaddr *)&sgw, 2351 (struct sockaddr *)NULL, RTF_GATEWAY | RTF_HOST, 2352 (struct sockaddr *)&ssrc, 2353 (struct rtentry **)NULL); 2354 } 2355 /* finally update cached route in each socket via pfctlinput */ 2356 { 2357 struct sockaddr_in6 sdst; 2358 2359 bzero(&sdst, sizeof(sdst)); 2360 sdst.sin6_family = AF_INET6; 2361 sdst.sin6_len = sizeof(struct sockaddr_in6); 2362 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2363 pfctlinput(PRC_REDIRECT_HOST, (struct sockaddr *)&sdst); 2364 #ifdef IPSEC 2365 key_sa_routechange((struct sockaddr *)&sdst); 2366 #endif 2367 } 2368 2369 freeit: 2370 m_freem(m); 2371 return; 2372 2373 bad: 2374 icmp6stat.icp6s_badredirect++; 2375 m_freem(m); 2376 } 2377 2378 void 2379 icmp6_redirect_output(struct mbuf *m0, struct rtentry *rt) 2380 { 2381 struct ifnet *ifp; /* my outgoing interface */ 2382 struct in6_addr *ifp_ll6; 2383 struct in6_addr *router_ll6; 2384 struct ip6_hdr *sip6; /* m0 as struct ip6_hdr */ 2385 struct mbuf *m = NULL; /* newly allocated one */ 2386 struct ip6_hdr *ip6; /* m as struct ip6_hdr */ 2387 struct nd_redirect *nd_rd; 2388 size_t maxlen; 2389 u_char *p; 2390 struct ifnet *outif = NULL; 2391 struct sockaddr_in6 src_sa; 2392 2393 icmp6_errcount(&icmp6stat.icp6s_outerrhist, ND_REDIRECT, 0); 2394 2395 /* if we are not router, we don't send icmp6 redirect */ 2396 if (!ip6_forwarding || ip6_accept_rtadv) 2397 goto fail; 2398 2399 /* sanity check */ 2400 if (!m0 || !rt || !(rt->rt_flags & RTF_UP) || !(ifp = rt->rt_ifp)) 2401 goto fail; 2402 2403 /* 2404 * Address check: 2405 * the source address must identify a neighbor, and 2406 * the destination address must not be a multicast address 2407 * [RFC 2461, sec 8.2] 2408 */ 2409 sip6 = mtod(m0, struct ip6_hdr *); 2410 bzero(&src_sa, sizeof(src_sa)); 2411 src_sa.sin6_family = AF_INET6; 2412 src_sa.sin6_len = sizeof(src_sa); 2413 src_sa.sin6_addr = sip6->ip6_src; 2414 /* we don't currently use sin6_scope_id, but eventually use it */ 2415 src_sa.sin6_scope_id = in6_addr2scopeid(ifp, &sip6->ip6_src); 2416 if (nd6_is_addr_neighbor(&src_sa, ifp) == 0) 2417 goto fail; 2418 if (IN6_IS_ADDR_MULTICAST(&sip6->ip6_dst)) 2419 goto fail; /* what should we do here? */ 2420 2421 /* rate limit */ 2422 if (icmp6_ratelimit(&sip6->ip6_src, ND_REDIRECT, 0)) 2423 goto fail; 2424 2425 /* 2426 * Since we are going to append up to 1280 bytes (= IPV6_MMTU), 2427 * we almost always ask for an mbuf cluster for simplicity. 2428 * (MHLEN < IPV6_MMTU is almost always true) 2429 */ 2430 #if IPV6_MMTU >= MCLBYTES 2431 # error assumption failed about IPV6_MMTU and MCLBYTES 2432 #endif 2433 MGETHDR(m, MB_DONTWAIT, MT_HEADER); 2434 if (m && IPV6_MMTU >= MHLEN) 2435 MCLGET(m, MB_DONTWAIT); 2436 if (!m) 2437 goto fail; 2438 m->m_pkthdr.rcvif = NULL; 2439 m->m_len = 0; 2440 maxlen = M_TRAILINGSPACE(m); 2441 maxlen = min(IPV6_MMTU, maxlen); 2442 /* just for safety */ 2443 if (maxlen < sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) + 2444 ((sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7)) { 2445 goto fail; 2446 } 2447 2448 { 2449 /* get ip6 linklocal address for ifp(my outgoing interface). */ 2450 struct in6_ifaddr *ia; 2451 if ((ia = in6ifa_ifpforlinklocal(ifp, 2452 IN6_IFF_NOTREADY| 2453 IN6_IFF_ANYCAST)) == NULL) 2454 goto fail; 2455 ifp_ll6 = &ia->ia_addr.sin6_addr; 2456 } 2457 2458 /* get ip6 linklocal address for the router. */ 2459 if (rt->rt_gateway && (rt->rt_flags & RTF_GATEWAY)) { 2460 struct sockaddr_in6 *sin6; 2461 sin6 = (struct sockaddr_in6 *)rt->rt_gateway; 2462 router_ll6 = &sin6->sin6_addr; 2463 if (!IN6_IS_ADDR_LINKLOCAL(router_ll6)) 2464 router_ll6 = (struct in6_addr *)NULL; 2465 } else 2466 router_ll6 = (struct in6_addr *)NULL; 2467 2468 /* ip6 */ 2469 ip6 = mtod(m, struct ip6_hdr *); 2470 ip6->ip6_flow = 0; 2471 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2472 ip6->ip6_vfc |= IPV6_VERSION; 2473 /* ip6->ip6_plen will be set later */ 2474 ip6->ip6_nxt = IPPROTO_ICMPV6; 2475 ip6->ip6_hlim = 255; 2476 /* ip6->ip6_src must be linklocal addr for my outgoing if. */ 2477 bcopy(ifp_ll6, &ip6->ip6_src, sizeof(struct in6_addr)); 2478 bcopy(&sip6->ip6_src, &ip6->ip6_dst, sizeof(struct in6_addr)); 2479 2480 /* ND Redirect */ 2481 nd_rd = (struct nd_redirect *)(ip6 + 1); 2482 nd_rd->nd_rd_type = ND_REDIRECT; 2483 nd_rd->nd_rd_code = 0; 2484 nd_rd->nd_rd_reserved = 0; 2485 if (rt->rt_flags & RTF_GATEWAY) { 2486 /* 2487 * nd_rd->nd_rd_target must be a link-local address in 2488 * better router cases. 2489 */ 2490 if (!router_ll6) 2491 goto fail; 2492 bcopy(router_ll6, &nd_rd->nd_rd_target, 2493 sizeof(nd_rd->nd_rd_target)); 2494 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2495 sizeof(nd_rd->nd_rd_dst)); 2496 } else { 2497 /* make sure redtgt == reddst */ 2498 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_target, 2499 sizeof(nd_rd->nd_rd_target)); 2500 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2501 sizeof(nd_rd->nd_rd_dst)); 2502 } 2503 2504 p = (u_char *)(nd_rd + 1); 2505 2506 if (!router_ll6) 2507 goto nolladdropt; 2508 2509 { 2510 /* target lladdr option */ 2511 struct rtentry *rt_router = NULL; 2512 int len; 2513 struct sockaddr_dl *sdl; 2514 struct nd_opt_hdr *nd_opt; 2515 char *lladdr; 2516 2517 rt_router = nd6_lookup(router_ll6, 0, ifp); 2518 if (!rt_router) 2519 goto nolladdropt; 2520 len = sizeof(*nd_opt) + ifp->if_addrlen; 2521 len = (len + 7) & ~7; /* round by 8 */ 2522 /* safety check */ 2523 if (len + (p - (u_char *)ip6) > maxlen) 2524 goto nolladdropt; 2525 if (!(rt_router->rt_flags & RTF_GATEWAY) && 2526 (rt_router->rt_flags & RTF_LLINFO) && 2527 (rt_router->rt_gateway->sa_family == AF_LINK) && 2528 (sdl = (struct sockaddr_dl *)rt_router->rt_gateway) && 2529 sdl->sdl_alen) { 2530 nd_opt = (struct nd_opt_hdr *)p; 2531 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 2532 nd_opt->nd_opt_len = len >> 3; 2533 lladdr = (char *)(nd_opt + 1); 2534 bcopy(LLADDR(sdl), lladdr, ifp->if_addrlen); 2535 p += len; 2536 } 2537 } 2538 nolladdropt:; 2539 2540 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2541 2542 /* just to be safe */ 2543 #ifdef M_DECRYPTED /*not openbsd*/ 2544 if (m0->m_flags & M_DECRYPTED) 2545 goto noredhdropt; 2546 #endif 2547 if (p - (u_char *)ip6 > maxlen) 2548 goto noredhdropt; 2549 2550 { 2551 /* redirected header option */ 2552 int len; 2553 struct nd_opt_rd_hdr *nd_opt_rh; 2554 2555 /* 2556 * compute the maximum size for icmp6 redirect header option. 2557 * XXX room for auth header? 2558 */ 2559 len = maxlen - (p - (u_char *)ip6); 2560 len &= ~7; 2561 2562 /* This is just for simplicity. */ 2563 if (m0->m_pkthdr.len != m0->m_len) { 2564 if (m0->m_next) { 2565 m_freem(m0->m_next); 2566 m0->m_next = NULL; 2567 } 2568 m0->m_pkthdr.len = m0->m_len; 2569 } 2570 2571 /* 2572 * Redirected header option spec (RFC2461 4.6.3) talks nothing 2573 * about padding/truncate rule for the original IP packet. 2574 * From the discussion on IPv6imp in Feb 1999, the consensus was: 2575 * - "attach as much as possible" is the goal 2576 * - pad if not aligned (original size can be guessed by original 2577 * ip6 header) 2578 * Following code adds the padding if it is simple enough, 2579 * and truncates if not. 2580 */ 2581 if (m0->m_next || m0->m_pkthdr.len != m0->m_len) 2582 panic("assumption failed in %s:%d", __FILE__, __LINE__); 2583 2584 if (len - sizeof(*nd_opt_rh) < m0->m_pkthdr.len) { 2585 /* not enough room, truncate */ 2586 m0->m_pkthdr.len = m0->m_len = len - sizeof(*nd_opt_rh); 2587 } else { 2588 /* enough room, pad or truncate */ 2589 size_t extra; 2590 2591 extra = m0->m_pkthdr.len % 8; 2592 if (extra) { 2593 /* pad if easy enough, truncate if not */ 2594 if (8 - extra <= M_TRAILINGSPACE(m0)) { 2595 /* pad */ 2596 m0->m_len += (8 - extra); 2597 m0->m_pkthdr.len += (8 - extra); 2598 } else { 2599 /* truncate */ 2600 m0->m_pkthdr.len -= extra; 2601 m0->m_len -= extra; 2602 } 2603 } 2604 len = m0->m_pkthdr.len + sizeof(*nd_opt_rh); 2605 m0->m_pkthdr.len = m0->m_len = len - sizeof(*nd_opt_rh); 2606 } 2607 2608 nd_opt_rh = (struct nd_opt_rd_hdr *)p; 2609 bzero(nd_opt_rh, sizeof(*nd_opt_rh)); 2610 nd_opt_rh->nd_opt_rh_type = ND_OPT_REDIRECTED_HEADER; 2611 nd_opt_rh->nd_opt_rh_len = len >> 3; 2612 p += sizeof(*nd_opt_rh); 2613 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2614 2615 /* connect m0 to m */ 2616 m->m_next = m0; 2617 m->m_pkthdr.len = m->m_len + m0->m_len; 2618 } 2619 noredhdropt:; 2620 2621 if (IN6_IS_ADDR_LINKLOCAL(&sip6->ip6_src)) 2622 sip6->ip6_src.s6_addr16[1] = 0; 2623 if (IN6_IS_ADDR_LINKLOCAL(&sip6->ip6_dst)) 2624 sip6->ip6_dst.s6_addr16[1] = 0; 2625 #if 0 2626 if (IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_src)) 2627 ip6->ip6_src.s6_addr16[1] = 0; 2628 if (IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_dst)) 2629 ip6->ip6_dst.s6_addr16[1] = 0; 2630 #endif 2631 if (IN6_IS_ADDR_LINKLOCAL(&nd_rd->nd_rd_target)) 2632 nd_rd->nd_rd_target.s6_addr16[1] = 0; 2633 if (IN6_IS_ADDR_LINKLOCAL(&nd_rd->nd_rd_dst)) 2634 nd_rd->nd_rd_dst.s6_addr16[1] = 0; 2635 2636 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr)); 2637 2638 nd_rd->nd_rd_cksum = 0; 2639 nd_rd->nd_rd_cksum 2640 = in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), ntohs(ip6->ip6_plen)); 2641 2642 /* send the packet to outside... */ 2643 ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL); 2644 if (outif) { 2645 icmp6_ifstat_inc(outif, ifs6_out_msg); 2646 icmp6_ifstat_inc(outif, ifs6_out_redirect); 2647 } 2648 icmp6stat.icp6s_outhist[ND_REDIRECT]++; 2649 2650 return; 2651 2652 fail: 2653 if (m) 2654 m_freem(m); 2655 if (m0) 2656 m_freem(m0); 2657 } 2658 2659 #ifdef HAVE_NRL_INPCB 2660 #define in6pcb inpcb 2661 #define in6p_icmp6filt inp_icmp6filt 2662 #endif 2663 /* 2664 * ICMPv6 socket option processing. 2665 */ 2666 int 2667 icmp6_ctloutput(struct socket *so, struct sockopt *sopt) 2668 { 2669 int error = 0; 2670 int optlen; 2671 struct inpcb *inp = so->so_pcb; 2672 int level, op, optname; 2673 2674 if (sopt) { 2675 level = sopt->sopt_level; 2676 op = sopt->sopt_dir; 2677 optname = sopt->sopt_name; 2678 optlen = sopt->sopt_valsize; 2679 } else 2680 level = op = optname = optlen = 0; 2681 2682 if (level != IPPROTO_ICMPV6) { 2683 return EINVAL; 2684 } 2685 2686 switch (op) { 2687 case PRCO_SETOPT: 2688 switch (optname) { 2689 case ICMP6_FILTER: 2690 { 2691 struct icmp6_filter *p; 2692 2693 if (optlen != sizeof(*p)) { 2694 error = EMSGSIZE; 2695 break; 2696 } 2697 if (inp->in6p_icmp6filt == NULL) { 2698 error = EINVAL; 2699 break; 2700 } 2701 error = sooptcopyin(sopt, inp->in6p_icmp6filt, optlen, 2702 optlen); 2703 break; 2704 } 2705 2706 default: 2707 error = ENOPROTOOPT; 2708 break; 2709 } 2710 break; 2711 2712 case PRCO_GETOPT: 2713 switch (optname) { 2714 case ICMP6_FILTER: 2715 { 2716 if (inp->in6p_icmp6filt == NULL) { 2717 error = EINVAL; 2718 break; 2719 } 2720 error = sooptcopyout(sopt, inp->in6p_icmp6filt, 2721 sizeof(struct icmp6_filter)); 2722 break; 2723 } 2724 2725 default: 2726 error = ENOPROTOOPT; 2727 break; 2728 } 2729 break; 2730 } 2731 2732 return(error); 2733 } 2734 #ifdef HAVE_NRL_INPCB 2735 #undef in6pcb 2736 #undef in6p_icmp6filt 2737 #endif 2738 2739 #ifndef HAVE_PPSRATECHECK 2740 #ifndef timersub 2741 #define timersub(tvp, uvp, vvp) \ 2742 do { \ 2743 (vvp)->tv_sec = (tvp)->tv_sec - (uvp)->tv_sec; \ 2744 (vvp)->tv_usec = (tvp)->tv_usec - (uvp)->tv_usec; \ 2745 if ((vvp)->tv_usec < 0) { \ 2746 (vvp)->tv_sec--; \ 2747 (vvp)->tv_usec += 1000000; \ 2748 } \ 2749 } while (0) 2750 #endif 2751 2752 /* 2753 * ppsratecheck(): packets (or events) per second limitation. 2754 */ 2755 static int 2756 ppsratecheck(struct timeval *lasttime, int *curpps, 2757 int maxpps) /* maximum pps allowed */ 2758 { 2759 struct timeval tv, delta; 2760 int rv; 2761 2762 microtime(&tv); 2763 2764 timersub(&tv, lasttime, &delta); 2765 2766 /* 2767 * Check for 0,0 so that the message will be seen at least once. 2768 * If more than one second has passed since the last update of 2769 * lasttime, reset the counter. 2770 * 2771 * We do increment *curpps even in *curpps < maxpps case, as some may 2772 * try to use *curpps for stat purposes as well. 2773 */ 2774 if ((lasttime->tv_sec == 0 && lasttime->tv_usec == 0) || 2775 delta.tv_sec >= 1) { 2776 *lasttime = tv; 2777 *curpps = 0; 2778 rv = 1; 2779 } else if (maxpps < 0) 2780 rv = 1; 2781 else if (*curpps < maxpps) 2782 rv = 1; 2783 else 2784 rv = 0; 2785 2786 #if 1 /* DIAGNOSTIC? */ 2787 /* be careful about wrap-around */ 2788 if (*curpps + 1 > *curpps) 2789 *curpps = *curpps + 1; 2790 #else 2791 /* 2792 * assume that there's not too many calls to this function. 2793 * not sure if the assumption holds, as it depends on *caller's* 2794 * behavior, not the behavior of this function. 2795 * IMHO it is wrong to make assumption on the caller's behavior, 2796 * so the above #if is #if 1, not #ifdef DIAGNOSTIC. 2797 */ 2798 *curpps = *curpps + 1; 2799 #endif 2800 2801 return (rv); 2802 } 2803 #endif 2804 2805 /* 2806 * Perform rate limit check. 2807 * Returns 0 if it is okay to send the icmp6 packet. 2808 * Returns 1 if the router SHOULD NOT send this icmp6 packet due to rate 2809 * limitation. 2810 * 2811 * XXX per-destination/type check necessary? 2812 */ 2813 static int 2814 icmp6_ratelimit(const struct in6_addr *dst, /* not used at this moment */ 2815 const int type, /* not used at this moment */ 2816 const int code) /* not used at this moment */ 2817 { 2818 int ret; 2819 2820 ret = 0; /* okay to send */ 2821 2822 /* PPS limit */ 2823 if (!ppsratecheck(&icmp6errppslim_last, &icmp6errpps_count, 2824 icmp6errppslim)) { 2825 /* The packet is subject to rate limit */ 2826 ret++; 2827 } 2828 2829 return ret; 2830 } 2831