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 1.21 2006/01/14 11:44:24 swildner 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 (*ctlfunc)(code, (struct sockaddr *)&icmp6dst, &ip6cp); 1104 } 1105 } 1106 return(0); 1107 1108 freeit: 1109 m_freem(m); 1110 return(-1); 1111 } 1112 1113 void 1114 icmp6_mtudisc_update(struct ip6ctlparam *ip6cp, int validated) 1115 { 1116 struct in6_addr *dst = ip6cp->ip6c_finaldst; 1117 struct icmp6_hdr *icmp6 = ip6cp->ip6c_icmp6; 1118 struct mbuf *m = ip6cp->ip6c_m; /* will be necessary for scope issue */ 1119 u_int mtu = ntohl(icmp6->icmp6_mtu); 1120 struct rtentry *rt = NULL; 1121 struct sockaddr_in6 sin6; 1122 1123 if (!validated) 1124 return; 1125 1126 bzero(&sin6, sizeof(sin6)); 1127 sin6.sin6_family = PF_INET6; 1128 sin6.sin6_len = sizeof(struct sockaddr_in6); 1129 sin6.sin6_addr = *dst; 1130 /* XXX normally, this won't happen */ 1131 if (IN6_IS_ADDR_LINKLOCAL(dst)) { 1132 sin6.sin6_addr.s6_addr16[1] = 1133 htons(m->m_pkthdr.rcvif->if_index); 1134 } 1135 /* sin6.sin6_scope_id = XXX: should be set if DST is a scoped addr */ 1136 rt = rtpurelookup((struct sockaddr *)&sin6); 1137 if (rt != NULL && (rt->rt_flags & RTF_HOST) && 1138 !(rt->rt_rmx.rmx_locks & RTV_MTU)) { 1139 if (mtu < IPV6_MMTU) { /* XXX */ 1140 rt->rt_rmx.rmx_locks |= RTV_MTU; 1141 } else if (mtu < rt->rt_ifp->if_mtu && 1142 rt->rt_rmx.rmx_mtu > mtu) { 1143 icmp6stat.icp6s_pmtuchg++; 1144 rt->rt_rmx.rmx_mtu = mtu; 1145 } 1146 } 1147 if (rt) 1148 --rt->rt_refcnt; 1149 } 1150 1151 /* 1152 * Process a Node Information Query packet, based on 1153 * draft-ietf-ipngwg-icmp-name-lookups-07. 1154 * 1155 * Spec incompatibilities: 1156 * - IPv6 Subject address handling 1157 * - IPv4 Subject address handling support missing 1158 * - Proxy reply (answer even if it's not for me) 1159 * - joins NI group address at in6_ifattach() time only, does not cope 1160 * with hostname changes by sethostname(3) 1161 */ 1162 #define hostnamelen strlen(hostname) 1163 static struct mbuf * 1164 ni6_input(struct mbuf *m, int off) 1165 { 1166 struct icmp6_nodeinfo *ni6, *nni6; 1167 struct mbuf *n = NULL; 1168 u_int16_t qtype; 1169 int subjlen; 1170 int replylen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo); 1171 struct ni_reply_fqdn *fqdn; 1172 int addrs; /* for NI_QTYPE_NODEADDR */ 1173 struct ifnet *ifp = NULL; /* for NI_QTYPE_NODEADDR */ 1174 struct sockaddr_in6 sin6; /* double meaning; ip6_dst and subjectaddr */ 1175 struct sockaddr_in6 sin6_d; /* XXX: we should retrieve this from m_aux */ 1176 struct ip6_hdr *ip6; 1177 int oldfqdn = 0; /* if 1, return pascal string (03 draft) */ 1178 char *subj = NULL; 1179 struct in6_ifaddr *ia6 = NULL; 1180 1181 ip6 = mtod(m, struct ip6_hdr *); 1182 #ifndef PULLDOWN_TEST 1183 ni6 = (struct icmp6_nodeinfo *)(mtod(m, caddr_t) + off); 1184 #else 1185 IP6_EXTHDR_GET(ni6, struct icmp6_nodeinfo *, m, off, sizeof(*ni6)); 1186 if (ni6 == NULL) { 1187 /* m is already reclaimed */ 1188 return NULL; 1189 } 1190 #endif 1191 1192 /* 1193 * Validate IPv6 destination address. 1194 * 1195 * The Responder must discard the Query without further processing 1196 * unless it is one of the Responder's unicast or anycast addresses, or 1197 * a link-local scope multicast address which the Responder has joined. 1198 * [icmp-name-lookups-07, Section 4.] 1199 */ 1200 bzero(&sin6, sizeof(sin6)); 1201 sin6.sin6_family = AF_INET6; 1202 sin6.sin6_len = sizeof(struct sockaddr_in6); 1203 bcopy(&ip6->ip6_dst, &sin6.sin6_addr, sizeof(sin6.sin6_addr)); 1204 /* XXX scopeid */ 1205 if ((ia6 = (struct in6_ifaddr *)ifa_ifwithaddr((struct sockaddr *)&sin6)) != NULL) { 1206 /* unicast/anycast, fine */ 1207 if ((ia6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 1208 (icmp6_nodeinfo & 4) == 0) { 1209 nd6log((LOG_DEBUG, "ni6_input: ignore node info to " 1210 "a temporary address in %s:%d", 1211 __FILE__, __LINE__)); 1212 goto bad; 1213 } 1214 } else if (IN6_IS_ADDR_MC_LINKLOCAL(&sin6.sin6_addr)) 1215 ; /* link-local multicast, fine */ 1216 else 1217 goto bad; 1218 1219 /* validate query Subject field. */ 1220 qtype = ntohs(ni6->ni_qtype); 1221 subjlen = m->m_pkthdr.len - off - sizeof(struct icmp6_nodeinfo); 1222 switch (qtype) { 1223 case NI_QTYPE_NOOP: 1224 case NI_QTYPE_SUPTYPES: 1225 /* 07 draft */ 1226 if (ni6->ni_code == ICMP6_NI_SUBJ_FQDN && subjlen == 0) 1227 break; 1228 /* FALLTHROUGH */ 1229 case NI_QTYPE_FQDN: 1230 case NI_QTYPE_NODEADDR: 1231 switch (ni6->ni_code) { 1232 case ICMP6_NI_SUBJ_IPV6: 1233 #if ICMP6_NI_SUBJ_IPV6 != 0 1234 case 0: 1235 #endif 1236 /* 1237 * backward compatibility - try to accept 03 draft 1238 * format, where no Subject is present. 1239 */ 1240 if (qtype == NI_QTYPE_FQDN && ni6->ni_code == 0 && 1241 subjlen == 0) { 1242 oldfqdn++; 1243 break; 1244 } 1245 #if ICMP6_NI_SUBJ_IPV6 != 0 1246 if (ni6->ni_code != ICMP6_NI_SUBJ_IPV6) 1247 goto bad; 1248 #endif 1249 1250 if (subjlen != sizeof(sin6.sin6_addr)) 1251 goto bad; 1252 1253 /* 1254 * Validate Subject address. 1255 * 1256 * Not sure what exactly "address belongs to the node" 1257 * means in the spec, is it just unicast, or what? 1258 * 1259 * At this moment we consider Subject address as 1260 * "belong to the node" if the Subject address equals 1261 * to the IPv6 destination address; validation for 1262 * IPv6 destination address should have done enough 1263 * check for us. 1264 * 1265 * We do not do proxy at this moment. 1266 */ 1267 /* m_pulldown instead of copy? */ 1268 m_copydata(m, off + sizeof(struct icmp6_nodeinfo), 1269 subjlen, (caddr_t)&sin6.sin6_addr); 1270 sin6.sin6_scope_id = in6_addr2scopeid(m->m_pkthdr.rcvif, 1271 &sin6.sin6_addr); 1272 in6_embedscope(&sin6.sin6_addr, &sin6, NULL, NULL); 1273 bzero(&sin6_d, sizeof(sin6_d)); 1274 sin6_d.sin6_family = AF_INET6; /* not used, actually */ 1275 sin6_d.sin6_len = sizeof(sin6_d); /* ditto */ 1276 sin6_d.sin6_addr = ip6->ip6_dst; 1277 sin6_d.sin6_scope_id = in6_addr2scopeid(m->m_pkthdr.rcvif, 1278 &ip6->ip6_dst); 1279 in6_embedscope(&sin6_d.sin6_addr, &sin6_d, NULL, NULL); 1280 subj = (char *)&sin6; 1281 if (SA6_ARE_ADDR_EQUAL(&sin6, &sin6_d)) 1282 break; 1283 1284 /* 1285 * XXX if we are to allow other cases, we should really 1286 * be careful about scope here. 1287 * basically, we should disallow queries toward IPv6 1288 * destination X with subject Y, if scope(X) > scope(Y). 1289 * if we allow scope(X) > scope(Y), it will result in 1290 * information leakage across scope boundary. 1291 */ 1292 goto bad; 1293 1294 case ICMP6_NI_SUBJ_FQDN: 1295 /* 1296 * Validate Subject name with gethostname(3). 1297 * 1298 * The behavior may need some debate, since: 1299 * - we are not sure if the node has FQDN as 1300 * hostname (returned by gethostname(3)). 1301 * - the code does wildcard match for truncated names. 1302 * however, we are not sure if we want to perform 1303 * wildcard match, if gethostname(3) side has 1304 * truncated hostname. 1305 */ 1306 n = ni6_nametodns(hostname, hostnamelen, 0); 1307 if (!n || n->m_next || n->m_len == 0) 1308 goto bad; 1309 IP6_EXTHDR_GET(subj, char *, m, 1310 off + sizeof(struct icmp6_nodeinfo), subjlen); 1311 if (subj == NULL) 1312 goto bad; 1313 if (!ni6_dnsmatch(subj, subjlen, mtod(n, const char *), 1314 n->m_len)) { 1315 goto bad; 1316 } 1317 m_freem(n); 1318 n = NULL; 1319 break; 1320 1321 case ICMP6_NI_SUBJ_IPV4: /* XXX: to be implemented? */ 1322 default: 1323 goto bad; 1324 } 1325 break; 1326 } 1327 1328 /* refuse based on configuration. XXX ICMP6_NI_REFUSED? */ 1329 switch (qtype) { 1330 case NI_QTYPE_FQDN: 1331 if ((icmp6_nodeinfo & 1) == 0) 1332 goto bad; 1333 break; 1334 case NI_QTYPE_NODEADDR: 1335 if ((icmp6_nodeinfo & 2) == 0) 1336 goto bad; 1337 break; 1338 } 1339 1340 /* guess reply length */ 1341 switch (qtype) { 1342 case NI_QTYPE_NOOP: 1343 break; /* no reply data */ 1344 case NI_QTYPE_SUPTYPES: 1345 replylen += sizeof(u_int32_t); 1346 break; 1347 case NI_QTYPE_FQDN: 1348 /* XXX will append an mbuf */ 1349 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1350 break; 1351 case NI_QTYPE_NODEADDR: 1352 addrs = ni6_addrs(ni6, m, &ifp, subj); 1353 if ((replylen += addrs * (sizeof(struct in6_addr) + 1354 sizeof(u_int32_t))) > MCLBYTES) 1355 replylen = MCLBYTES; /* XXX: will truncate pkt later */ 1356 break; 1357 default: 1358 /* 1359 * XXX: We must return a reply with the ICMP6 code 1360 * `unknown Qtype' in this case. However we regard the case 1361 * as an FQDN query for backward compatibility. 1362 * Older versions set a random value to this field, 1363 * so it rarely varies in the defined qtypes. 1364 * But the mechanism is not reliable... 1365 * maybe we should obsolete older versions. 1366 */ 1367 qtype = NI_QTYPE_FQDN; 1368 /* XXX will append an mbuf */ 1369 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1370 oldfqdn++; 1371 break; 1372 } 1373 1374 /* allocate an mbuf to reply. */ 1375 MGETHDR(n, MB_DONTWAIT, m->m_type); 1376 if (n == NULL) { 1377 m_freem(m); 1378 return(NULL); 1379 } 1380 M_MOVE_PKTHDR(n, m); /* just for recvif */ 1381 if (replylen > MHLEN) { 1382 if (replylen > MCLBYTES) { 1383 /* 1384 * XXX: should we try to allocate more? But MCLBYTES 1385 * is probably much larger than IPV6_MMTU... 1386 */ 1387 goto bad; 1388 } 1389 MCLGET(n, MB_DONTWAIT); 1390 if ((n->m_flags & M_EXT) == 0) { 1391 goto bad; 1392 } 1393 } 1394 n->m_pkthdr.len = n->m_len = replylen; 1395 1396 /* copy mbuf header and IPv6 + Node Information base headers */ 1397 bcopy(mtod(m, caddr_t), mtod(n, caddr_t), sizeof(struct ip6_hdr)); 1398 nni6 = (struct icmp6_nodeinfo *)(mtod(n, struct ip6_hdr *) + 1); 1399 bcopy((caddr_t)ni6, (caddr_t)nni6, sizeof(struct icmp6_nodeinfo)); 1400 1401 /* qtype dependent procedure */ 1402 switch (qtype) { 1403 case NI_QTYPE_NOOP: 1404 nni6->ni_code = ICMP6_NI_SUCCESS; 1405 nni6->ni_flags = 0; 1406 break; 1407 case NI_QTYPE_SUPTYPES: 1408 { 1409 u_int32_t v; 1410 nni6->ni_code = ICMP6_NI_SUCCESS; 1411 nni6->ni_flags = htons(0x0000); /* raw bitmap */ 1412 /* supports NOOP, SUPTYPES, FQDN, and NODEADDR */ 1413 v = (u_int32_t)htonl(0x0000000f); 1414 bcopy(&v, nni6 + 1, sizeof(u_int32_t)); 1415 break; 1416 } 1417 case NI_QTYPE_FQDN: 1418 nni6->ni_code = ICMP6_NI_SUCCESS; 1419 fqdn = (struct ni_reply_fqdn *)(mtod(n, caddr_t) + 1420 sizeof(struct ip6_hdr) + 1421 sizeof(struct icmp6_nodeinfo)); 1422 nni6->ni_flags = 0; /* XXX: meaningless TTL */ 1423 fqdn->ni_fqdn_ttl = 0; /* ditto. */ 1424 /* 1425 * XXX do we really have FQDN in variable "hostname"? 1426 */ 1427 n->m_next = ni6_nametodns(hostname, hostnamelen, oldfqdn); 1428 if (n->m_next == NULL) 1429 goto bad; 1430 /* XXX we assume that n->m_next is not a chain */ 1431 if (n->m_next->m_next != NULL) 1432 goto bad; 1433 n->m_pkthdr.len += n->m_next->m_len; 1434 break; 1435 case NI_QTYPE_NODEADDR: 1436 { 1437 int lenlim, copied; 1438 1439 nni6->ni_code = ICMP6_NI_SUCCESS; 1440 n->m_pkthdr.len = n->m_len = 1441 sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo); 1442 lenlim = M_TRAILINGSPACE(n); 1443 copied = ni6_store_addrs(ni6, nni6, ifp, lenlim); 1444 /* XXX: reset mbuf length */ 1445 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) + 1446 sizeof(struct icmp6_nodeinfo) + copied; 1447 break; 1448 } 1449 default: 1450 break; /* XXX impossible! */ 1451 } 1452 1453 nni6->ni_type = ICMP6_NI_REPLY; 1454 m_freem(m); 1455 return(n); 1456 1457 bad: 1458 m_freem(m); 1459 if (n) 1460 m_freem(n); 1461 return(NULL); 1462 } 1463 #undef hostnamelen 1464 1465 /* 1466 * make a mbuf with DNS-encoded string. no compression support. 1467 * 1468 * XXX names with less than 2 dots (like "foo" or "foo.section") will be 1469 * treated as truncated name (two \0 at the end). this is a wild guess. 1470 */ 1471 static struct mbuf * 1472 ni6_nametodns(const char *name, int namelen, 1473 int old) /* return pascal string if non-zero */ 1474 { 1475 struct mbuf *m; 1476 char *cp, *ep; 1477 const char *p, *q; 1478 int i, len, nterm; 1479 1480 if (old) 1481 len = namelen + 1; 1482 else 1483 len = MCLBYTES; 1484 1485 /* because MAXHOSTNAMELEN is usually 256, we use cluster mbuf */ 1486 MGET(m, MB_DONTWAIT, MT_DATA); 1487 if (m && len > MLEN) { 1488 MCLGET(m, MB_DONTWAIT); 1489 if ((m->m_flags & M_EXT) == 0) 1490 goto fail; 1491 } 1492 if (!m) 1493 goto fail; 1494 m->m_next = NULL; 1495 1496 if (old) { 1497 m->m_len = len; 1498 *mtod(m, char *) = namelen; 1499 bcopy(name, mtod(m, char *) + 1, namelen); 1500 return m; 1501 } else { 1502 m->m_len = 0; 1503 cp = mtod(m, char *); 1504 ep = mtod(m, char *) + M_TRAILINGSPACE(m); 1505 1506 /* if not certain about my name, return empty buffer */ 1507 if (namelen == 0) 1508 return m; 1509 1510 /* 1511 * guess if it looks like shortened hostname, or FQDN. 1512 * shortened hostname needs two trailing "\0". 1513 */ 1514 i = 0; 1515 for (p = name; p < name + namelen; p++) { 1516 if (*p && *p == '.') 1517 i++; 1518 } 1519 if (i < 2) 1520 nterm = 2; 1521 else 1522 nterm = 1; 1523 1524 p = name; 1525 while (cp < ep && p < name + namelen) { 1526 i = 0; 1527 for (q = p; q < name + namelen && *q && *q != '.'; q++) 1528 i++; 1529 /* result does not fit into mbuf */ 1530 if (cp + i + 1 >= ep) 1531 goto fail; 1532 /* 1533 * DNS label length restriction, RFC1035 page 8. 1534 * "i == 0" case is included here to avoid returning 1535 * 0-length label on "foo..bar". 1536 */ 1537 if (i <= 0 || i >= 64) 1538 goto fail; 1539 *cp++ = i; 1540 bcopy(p, cp, i); 1541 cp += i; 1542 p = q; 1543 if (p < name + namelen && *p == '.') 1544 p++; 1545 } 1546 /* termination */ 1547 if (cp + nterm >= ep) 1548 goto fail; 1549 while (nterm-- > 0) 1550 *cp++ = '\0'; 1551 m->m_len = cp - mtod(m, char *); 1552 return m; 1553 } 1554 1555 panic("should not reach here"); 1556 /* NOTREACHED */ 1557 1558 fail: 1559 if (m) 1560 m_freem(m); 1561 return NULL; 1562 } 1563 1564 /* 1565 * check if two DNS-encoded string matches. takes care of truncated 1566 * form (with \0\0 at the end). no compression support. 1567 * XXX upper/lowercase match (see RFC2065) 1568 */ 1569 static int 1570 ni6_dnsmatch(const char *a, int alen, const char *b, int blen) 1571 { 1572 const char *a0, *b0; 1573 int l; 1574 1575 /* simplest case - need validation? */ 1576 if (alen == blen && bcmp(a, b, alen) == 0) 1577 return 1; 1578 1579 a0 = a; 1580 b0 = b; 1581 1582 /* termination is mandatory */ 1583 if (alen < 2 || blen < 2) 1584 return 0; 1585 if (a0[alen - 1] != '\0' || b0[blen - 1] != '\0') 1586 return 0; 1587 alen--; 1588 blen--; 1589 1590 while (a - a0 < alen && b - b0 < blen) { 1591 if (a - a0 + 1 > alen || b - b0 + 1 > blen) 1592 return 0; 1593 1594 if ((signed char)a[0] < 0 || (signed char)b[0] < 0) 1595 return 0; 1596 /* we don't support compression yet */ 1597 if (a[0] >= 64 || b[0] >= 64) 1598 return 0; 1599 1600 /* truncated case */ 1601 if (a[0] == 0 && a - a0 == alen - 1) 1602 return 1; 1603 if (b[0] == 0 && b - b0 == blen - 1) 1604 return 1; 1605 if (a[0] == 0 || b[0] == 0) 1606 return 0; 1607 1608 if (a[0] != b[0]) 1609 return 0; 1610 l = a[0]; 1611 if (a - a0 + 1 + l > alen || b - b0 + 1 + l > blen) 1612 return 0; 1613 if (bcmp(a + 1, b + 1, l) != 0) 1614 return 0; 1615 1616 a += 1 + l; 1617 b += 1 + l; 1618 } 1619 1620 if (a - a0 == alen && b - b0 == blen) 1621 return 1; 1622 else 1623 return 0; 1624 } 1625 1626 /* 1627 * calculate the number of addresses to be returned in the node info reply. 1628 */ 1629 static int 1630 ni6_addrs(struct icmp6_nodeinfo *ni6, struct mbuf *m, struct ifnet **ifpp, 1631 char *subj) 1632 { 1633 struct ifnet *ifp; 1634 struct in6_ifaddr *ifa6; 1635 struct ifaddr *ifa; 1636 struct sockaddr_in6 *subj_ip6 = NULL; /* XXX pedant */ 1637 int addrs = 0, addrsofif, iffound = 0; 1638 int niflags = ni6->ni_flags; 1639 1640 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0) { 1641 switch (ni6->ni_code) { 1642 case ICMP6_NI_SUBJ_IPV6: 1643 if (subj == NULL) /* must be impossible... */ 1644 return(0); 1645 subj_ip6 = (struct sockaddr_in6 *)subj; 1646 break; 1647 default: 1648 /* 1649 * XXX: we only support IPv6 subject address for 1650 * this Qtype. 1651 */ 1652 return(0); 1653 } 1654 } 1655 1656 for (ifp = TAILQ_FIRST(&ifnet); ifp; ifp = TAILQ_NEXT(ifp, if_list)) 1657 { 1658 addrsofif = 0; 1659 TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list) 1660 { 1661 if (ifa->ifa_addr->sa_family != AF_INET6) 1662 continue; 1663 ifa6 = (struct in6_ifaddr *)ifa; 1664 1665 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0 && 1666 IN6_ARE_ADDR_EQUAL(&subj_ip6->sin6_addr, 1667 &ifa6->ia_addr.sin6_addr)) 1668 iffound = 1; 1669 1670 /* 1671 * IPv4-mapped addresses can only be returned by a 1672 * Node Information proxy, since they represent 1673 * addresses of IPv4-only nodes, which perforce do 1674 * not implement this protocol. 1675 * [icmp-name-lookups-07, Section 5.4] 1676 * So we don't support NI_NODEADDR_FLAG_COMPAT in 1677 * this function at this moment. 1678 */ 1679 1680 /* What do we have to do about ::1? */ 1681 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1682 case IPV6_ADDR_SCOPE_LINKLOCAL: 1683 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0) 1684 continue; 1685 break; 1686 case IPV6_ADDR_SCOPE_SITELOCAL: 1687 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0) 1688 continue; 1689 break; 1690 case IPV6_ADDR_SCOPE_GLOBAL: 1691 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0) 1692 continue; 1693 break; 1694 default: 1695 continue; 1696 } 1697 1698 /* 1699 * check if anycast is okay. 1700 * XXX: just experimental. not in the spec. 1701 */ 1702 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 && 1703 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0) 1704 continue; /* we need only unicast addresses */ 1705 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 1706 (icmp6_nodeinfo & 4) == 0) { 1707 continue; 1708 } 1709 addrsofif++; /* count the address */ 1710 } 1711 if (iffound) { 1712 *ifpp = ifp; 1713 return(addrsofif); 1714 } 1715 1716 addrs += addrsofif; 1717 } 1718 1719 return(addrs); 1720 } 1721 1722 static int 1723 ni6_store_addrs(struct icmp6_nodeinfo *ni6, struct icmp6_nodeinfo *nni6, 1724 struct ifnet *ifp0, int resid) 1725 { 1726 struct ifnet *ifp = ifp0 ? ifp0 : TAILQ_FIRST(&ifnet); 1727 struct in6_ifaddr *ifa6; 1728 struct ifaddr *ifa; 1729 struct ifnet *ifp_dep = NULL; 1730 int copied = 0, allow_deprecated = 0; 1731 u_char *cp = (u_char *)(nni6 + 1); 1732 int niflags = ni6->ni_flags; 1733 u_int32_t ltime; 1734 1735 if (ifp0 == NULL && !(niflags & NI_NODEADDR_FLAG_ALL)) 1736 return(0); /* needless to copy */ 1737 1738 again: 1739 1740 for (; ifp; ifp = TAILQ_NEXT(ifp, if_list)) 1741 { 1742 TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list) { 1743 if (ifa->ifa_addr->sa_family != AF_INET6) 1744 continue; 1745 ifa6 = (struct in6_ifaddr *)ifa; 1746 1747 if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) != 0 && 1748 allow_deprecated == 0) { 1749 /* 1750 * prefererred address should be put before 1751 * deprecated addresses. 1752 */ 1753 1754 /* record the interface for later search */ 1755 if (ifp_dep == NULL) 1756 ifp_dep = ifp; 1757 1758 continue; 1759 } 1760 else if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) == 0 && 1761 allow_deprecated != 0) 1762 continue; /* we now collect deprecated addrs */ 1763 1764 /* What do we have to do about ::1? */ 1765 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1766 case IPV6_ADDR_SCOPE_LINKLOCAL: 1767 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0) 1768 continue; 1769 break; 1770 case IPV6_ADDR_SCOPE_SITELOCAL: 1771 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0) 1772 continue; 1773 break; 1774 case IPV6_ADDR_SCOPE_GLOBAL: 1775 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0) 1776 continue; 1777 break; 1778 default: 1779 continue; 1780 } 1781 1782 /* 1783 * check if anycast is okay. 1784 * XXX: just experimental. not in the spec. 1785 */ 1786 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 && 1787 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0) 1788 continue; 1789 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 1790 (icmp6_nodeinfo & 4) == 0) { 1791 continue; 1792 } 1793 1794 /* now we can copy the address */ 1795 if (resid < sizeof(struct in6_addr) + 1796 sizeof(u_int32_t)) { 1797 /* 1798 * We give up much more copy. 1799 * Set the truncate flag and return. 1800 */ 1801 nni6->ni_flags |= 1802 NI_NODEADDR_FLAG_TRUNCATE; 1803 return(copied); 1804 } 1805 1806 /* 1807 * Set the TTL of the address. 1808 * The TTL value should be one of the following 1809 * according to the specification: 1810 * 1811 * 1. The remaining lifetime of a DHCP lease on the 1812 * address, or 1813 * 2. The remaining Valid Lifetime of a prefix from 1814 * which the address was derived through Stateless 1815 * Autoconfiguration. 1816 * 1817 * Note that we currently do not support stateful 1818 * address configuration by DHCPv6, so the former 1819 * case can't happen. 1820 */ 1821 if (ifa6->ia6_lifetime.ia6t_expire == 0) 1822 ltime = ND6_INFINITE_LIFETIME; 1823 else { 1824 if (ifa6->ia6_lifetime.ia6t_expire > 1825 time_second) 1826 ltime = htonl(ifa6->ia6_lifetime.ia6t_expire - time_second); 1827 else 1828 ltime = 0; 1829 } 1830 1831 bcopy(<ime, cp, sizeof(u_int32_t)); 1832 cp += sizeof(u_int32_t); 1833 1834 /* copy the address itself */ 1835 bcopy(&ifa6->ia_addr.sin6_addr, cp, 1836 sizeof(struct in6_addr)); 1837 /* XXX: KAME link-local hack; remove ifindex */ 1838 if (IN6_IS_ADDR_LINKLOCAL(&ifa6->ia_addr.sin6_addr)) 1839 ((struct in6_addr *)cp)->s6_addr16[1] = 0; 1840 cp += sizeof(struct in6_addr); 1841 1842 resid -= (sizeof(struct in6_addr) + sizeof(u_int32_t)); 1843 copied += (sizeof(struct in6_addr) + 1844 sizeof(u_int32_t)); 1845 } 1846 if (ifp0) /* we need search only on the specified IF */ 1847 break; 1848 } 1849 1850 if (allow_deprecated == 0 && ifp_dep != NULL) { 1851 ifp = ifp_dep; 1852 allow_deprecated = 1; 1853 1854 goto again; 1855 } 1856 1857 return(copied); 1858 } 1859 1860 /* 1861 * XXX almost dup'ed code with rip6_input. 1862 */ 1863 static int 1864 icmp6_rip6_input(struct mbuf **mp, int off) 1865 { 1866 struct mbuf *m = *mp; 1867 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1868 struct in6pcb *in6p; 1869 struct in6pcb *last = NULL; 1870 struct sockaddr_in6 rip6src; 1871 struct icmp6_hdr *icmp6; 1872 struct mbuf *opts = NULL; 1873 1874 #ifndef PULLDOWN_TEST 1875 /* this is assumed to be safe. */ 1876 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off); 1877 #else 1878 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 1879 if (icmp6 == NULL) { 1880 /* m is already reclaimed */ 1881 return IPPROTO_DONE; 1882 } 1883 #endif 1884 1885 bzero(&rip6src, sizeof(rip6src)); 1886 rip6src.sin6_len = sizeof(struct sockaddr_in6); 1887 rip6src.sin6_family = AF_INET6; 1888 /* KAME hack: recover scopeid */ 1889 in6_recoverscope(&rip6src, &ip6->ip6_src, m->m_pkthdr.rcvif); 1890 1891 LIST_FOREACH(in6p, &ripcbinfo.pcblisthead, inp_list) 1892 { 1893 if (in6p->inp_flags & INP_PLACEMARKER) 1894 continue; 1895 if ((in6p->inp_vflag & INP_IPV6) == 0) 1896 continue; 1897 #ifdef HAVE_NRL_INPCB 1898 if (!(in6p->in6p_flags & INP_IPV6)) 1899 continue; 1900 #endif 1901 if (in6p->in6p_ip6_nxt != IPPROTO_ICMPV6) 1902 continue; 1903 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr) && 1904 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr, &ip6->ip6_dst)) 1905 continue; 1906 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr) && 1907 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr, &ip6->ip6_src)) 1908 continue; 1909 if (in6p->in6p_icmp6filt 1910 && ICMP6_FILTER_WILLBLOCK(icmp6->icmp6_type, 1911 in6p->in6p_icmp6filt)) 1912 continue; 1913 if (last) { 1914 struct mbuf *n; 1915 if ((n = m_copy(m, 0, (int)M_COPYALL)) != NULL) { 1916 if (last->in6p_flags & IN6P_CONTROLOPTS) 1917 ip6_savecontrol(last, &opts, ip6, n); 1918 /* strip intermediate headers */ 1919 m_adj(n, off); 1920 if (sbappendaddr(&last->in6p_socket->so_rcv, 1921 (struct sockaddr *)&rip6src, 1922 n, opts) == 0) { 1923 /* should notify about lost packet */ 1924 m_freem(n); 1925 if (opts) { 1926 m_freem(opts); 1927 } 1928 } else 1929 sorwakeup(last->in6p_socket); 1930 opts = NULL; 1931 } 1932 } 1933 last = in6p; 1934 } 1935 if (last) { 1936 if (last->in6p_flags & IN6P_CONTROLOPTS) 1937 ip6_savecontrol(last, &opts, ip6, m); 1938 /* strip intermediate headers */ 1939 m_adj(m, off); 1940 if (sbappendaddr(&last->in6p_socket->so_rcv, 1941 (struct sockaddr *)&rip6src, m, opts) == 0) { 1942 m_freem(m); 1943 if (opts) 1944 m_freem(opts); 1945 } else 1946 sorwakeup(last->in6p_socket); 1947 } else { 1948 m_freem(m); 1949 ip6stat.ip6s_delivered--; 1950 } 1951 return IPPROTO_DONE; 1952 } 1953 1954 /* 1955 * Reflect the ip6 packet back to the source. 1956 * OFF points to the icmp6 header, counted from the top of the mbuf. 1957 */ 1958 void 1959 icmp6_reflect(struct mbuf *m, size_t off) 1960 { 1961 struct ip6_hdr *ip6; 1962 struct icmp6_hdr *icmp6; 1963 struct in6_ifaddr *ia; 1964 struct in6_addr t, *src = 0; 1965 int plen; 1966 int type, code; 1967 struct ifnet *outif = NULL; 1968 struct sockaddr_in6 sa6_src, sa6_dst; 1969 #ifdef COMPAT_RFC1885 1970 int mtu = IPV6_MMTU; 1971 struct sockaddr_in6 *sin6 = &icmp6_reflect_rt.ro_dst; 1972 #endif 1973 1974 /* too short to reflect */ 1975 if (off < sizeof(struct ip6_hdr)) { 1976 nd6log((LOG_DEBUG, 1977 "sanity fail: off=%lx, sizeof(ip6)=%lx in %s:%d\n", 1978 (u_long)off, (u_long)sizeof(struct ip6_hdr), 1979 __FILE__, __LINE__)); 1980 goto bad; 1981 } 1982 1983 /* 1984 * If there are extra headers between IPv6 and ICMPv6, strip 1985 * off that header first. 1986 */ 1987 #ifdef DIAGNOSTIC 1988 if (sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) > MHLEN) 1989 panic("assumption failed in icmp6_reflect"); 1990 #endif 1991 if (off > sizeof(struct ip6_hdr)) { 1992 size_t l; 1993 struct ip6_hdr nip6; 1994 1995 l = off - sizeof(struct ip6_hdr); 1996 m_copydata(m, 0, sizeof(nip6), (caddr_t)&nip6); 1997 m_adj(m, l); 1998 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 1999 if (m->m_len < l) { 2000 if ((m = m_pullup(m, l)) == NULL) 2001 return; 2002 } 2003 bcopy((caddr_t)&nip6, mtod(m, caddr_t), sizeof(nip6)); 2004 } else /* off == sizeof(struct ip6_hdr) */ { 2005 size_t l; 2006 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 2007 if (m->m_len < l) { 2008 if ((m = m_pullup(m, l)) == NULL) 2009 return; 2010 } 2011 } 2012 plen = m->m_pkthdr.len - sizeof(struct ip6_hdr); 2013 ip6 = mtod(m, struct ip6_hdr *); 2014 ip6->ip6_nxt = IPPROTO_ICMPV6; 2015 icmp6 = (struct icmp6_hdr *)(ip6 + 1); 2016 type = icmp6->icmp6_type; /* keep type for statistics */ 2017 code = icmp6->icmp6_code; /* ditto. */ 2018 2019 t = ip6->ip6_dst; 2020 /* 2021 * ip6_input() drops a packet if its src is multicast. 2022 * So, the src is never multicast. 2023 */ 2024 ip6->ip6_dst = ip6->ip6_src; 2025 2026 /* 2027 * XXX: make sure to embed scope zone information, using 2028 * already embedded IDs or the received interface (if any). 2029 * Note that rcvif may be NULL. 2030 * TODO: scoped routing case (XXX). 2031 */ 2032 bzero(&sa6_src, sizeof(sa6_src)); 2033 sa6_src.sin6_family = AF_INET6; 2034 sa6_src.sin6_len = sizeof(sa6_src); 2035 sa6_src.sin6_addr = ip6->ip6_dst; 2036 in6_recoverscope(&sa6_src, &ip6->ip6_dst, m->m_pkthdr.rcvif); 2037 in6_embedscope(&ip6->ip6_dst, &sa6_src, NULL, NULL); 2038 bzero(&sa6_dst, sizeof(sa6_dst)); 2039 sa6_dst.sin6_family = AF_INET6; 2040 sa6_dst.sin6_len = sizeof(sa6_dst); 2041 sa6_dst.sin6_addr = t; 2042 in6_recoverscope(&sa6_dst, &t, m->m_pkthdr.rcvif); 2043 in6_embedscope(&t, &sa6_dst, NULL, NULL); 2044 2045 #ifdef COMPAT_RFC1885 2046 /* 2047 * xxx guess MTU 2048 * RFC 1885 requires that echo reply should be truncated if it 2049 * does not fit in with (return) path MTU, but the description was 2050 * removed in the new spec. 2051 */ 2052 if (icmp6_reflect_rt.ro_rt == 0 || 2053 ! (IN6_ARE_ADDR_EQUAL(&sin6->sin6_addr, &ip6->ip6_dst))) { 2054 if (icmp6_reflect_rt.ro_rt) { 2055 RTFREE(icmp6_reflect_rt.ro_rt); 2056 icmp6_reflect_rt.ro_rt = 0; 2057 } 2058 bzero(sin6, sizeof(*sin6)); 2059 sin6->sin6_family = PF_INET6; 2060 sin6->sin6_len = sizeof(struct sockaddr_in6); 2061 sin6->sin6_addr = ip6->ip6_dst; 2062 2063 rtalloc_ign((struct route *)&icmp6_reflect_rt.ro_rt, 2064 RTF_PRCLONING); 2065 } 2066 2067 if (icmp6_reflect_rt.ro_rt == 0) 2068 goto bad; 2069 2070 if ((icmp6_reflect_rt.ro_rt->rt_flags & RTF_HOST) 2071 && mtu < icmp6_reflect_rt.ro_rt->rt_ifp->if_mtu) 2072 mtu = icmp6_reflect_rt.ro_rt->rt_rmx.rmx_mtu; 2073 2074 if (mtu < m->m_pkthdr.len) { 2075 plen -= (m->m_pkthdr.len - mtu); 2076 m_adj(m, mtu - m->m_pkthdr.len); 2077 } 2078 #endif 2079 /* 2080 * If the incoming packet was addressed directly to us(i.e. unicast), 2081 * use dst as the src for the reply. 2082 * The IN6_IFF_NOTREADY case would be VERY rare, but is possible 2083 * (for example) when we encounter an error while forwarding procedure 2084 * destined to a duplicated address of ours. 2085 */ 2086 for (ia = in6_ifaddr; ia; ia = ia->ia_next) 2087 if (IN6_ARE_ADDR_EQUAL(&t, &ia->ia_addr.sin6_addr) && 2088 (ia->ia6_flags & (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY)) == 0) { 2089 src = &t; 2090 break; 2091 } 2092 if (ia == NULL && IN6_IS_ADDR_LINKLOCAL(&t) && (m->m_flags & M_LOOP)) { 2093 /* 2094 * This is the case if the dst is our link-local address 2095 * and the sender is also ourselves. 2096 */ 2097 src = &t; 2098 } 2099 2100 if (src == 0) { 2101 int e; 2102 struct route_in6 ro; 2103 2104 /* 2105 * This case matches to multicasts, our anycast, or unicasts 2106 * that we do not own. Select a source address based on the 2107 * source address of the erroneous packet. 2108 */ 2109 bzero(&ro, sizeof(ro)); 2110 src = in6_selectsrc(&sa6_src, NULL, NULL, &ro, NULL, &e); 2111 if (ro.ro_rt) 2112 RTFREE(ro.ro_rt); /* XXX: we could use this */ 2113 if (src == NULL) { 2114 nd6log((LOG_DEBUG, 2115 "icmp6_reflect: source can't be determined: " 2116 "dst=%s, error=%d\n", 2117 ip6_sprintf(&sa6_src.sin6_addr), e)); 2118 goto bad; 2119 } 2120 } 2121 2122 ip6->ip6_src = *src; 2123 2124 ip6->ip6_flow = 0; 2125 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2126 ip6->ip6_vfc |= IPV6_VERSION; 2127 ip6->ip6_nxt = IPPROTO_ICMPV6; 2128 if (m->m_pkthdr.rcvif) { 2129 /* XXX: This may not be the outgoing interface */ 2130 ip6->ip6_hlim = ND_IFINFO(m->m_pkthdr.rcvif)->chlim; 2131 } else 2132 ip6->ip6_hlim = ip6_defhlim; 2133 2134 icmp6->icmp6_cksum = 0; 2135 icmp6->icmp6_cksum = in6_cksum(m, IPPROTO_ICMPV6, 2136 sizeof(struct ip6_hdr), plen); 2137 2138 /* 2139 * XXX option handling 2140 */ 2141 2142 m->m_flags &= ~(M_BCAST|M_MCAST); 2143 2144 #ifdef COMPAT_RFC1885 2145 ip6_output(m, NULL, &icmp6_reflect_rt, 0, NULL, &outif, NULL); 2146 #else 2147 ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL); 2148 #endif 2149 if (outif) 2150 icmp6_ifoutstat_inc(outif, type, code); 2151 2152 return; 2153 2154 bad: 2155 m_freem(m); 2156 return; 2157 } 2158 2159 void 2160 icmp6_fasttimo(void) 2161 { 2162 2163 mld6_fasttimeo(); 2164 } 2165 2166 static const char * 2167 icmp6_redirect_diag(struct in6_addr *src6, struct in6_addr *dst6, 2168 struct in6_addr *tgt6) 2169 { 2170 static char buf[1024]; 2171 snprintf(buf, sizeof(buf), "(src=%s dst=%s tgt=%s)", 2172 ip6_sprintf(src6), ip6_sprintf(dst6), ip6_sprintf(tgt6)); 2173 return buf; 2174 } 2175 2176 void 2177 icmp6_redirect_input(struct mbuf *m, int off) 2178 { 2179 struct ifnet *ifp = m->m_pkthdr.rcvif; 2180 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 2181 struct nd_redirect *nd_rd; 2182 int icmp6len = ntohs(ip6->ip6_plen); 2183 char *lladdr = NULL; 2184 int lladdrlen = 0; 2185 u_char *redirhdr = NULL; 2186 int redirhdrlen = 0; 2187 struct rtentry *rt = NULL; 2188 int is_router; 2189 int is_onlink; 2190 struct in6_addr src6 = ip6->ip6_src; 2191 struct in6_addr redtgt6; 2192 struct in6_addr reddst6; 2193 union nd_opts ndopts; 2194 2195 if (!m || !ifp) 2196 return; 2197 2198 /* XXX if we are router, we don't update route by icmp6 redirect */ 2199 if (ip6_forwarding) 2200 goto freeit; 2201 if (!icmp6_rediraccept) 2202 goto freeit; 2203 2204 #ifndef PULLDOWN_TEST 2205 IP6_EXTHDR_CHECK(m, off, icmp6len,); 2206 nd_rd = (struct nd_redirect *)((caddr_t)ip6 + off); 2207 #else 2208 IP6_EXTHDR_GET(nd_rd, struct nd_redirect *, m, off, icmp6len); 2209 if (nd_rd == NULL) { 2210 icmp6stat.icp6s_tooshort++; 2211 return; 2212 } 2213 #endif 2214 redtgt6 = nd_rd->nd_rd_target; 2215 reddst6 = nd_rd->nd_rd_dst; 2216 2217 if (IN6_IS_ADDR_LINKLOCAL(&redtgt6)) 2218 redtgt6.s6_addr16[1] = htons(ifp->if_index); 2219 if (IN6_IS_ADDR_LINKLOCAL(&reddst6)) 2220 reddst6.s6_addr16[1] = htons(ifp->if_index); 2221 2222 /* validation */ 2223 if (!IN6_IS_ADDR_LINKLOCAL(&src6)) { 2224 nd6log((LOG_ERR, 2225 "ICMP6 redirect sent from %s rejected; " 2226 "must be from linklocal\n", ip6_sprintf(&src6))); 2227 goto bad; 2228 } 2229 if (ip6->ip6_hlim != 255) { 2230 nd6log((LOG_ERR, 2231 "ICMP6 redirect sent from %s rejected; " 2232 "hlim=%d (must be 255)\n", 2233 ip6_sprintf(&src6), ip6->ip6_hlim)); 2234 goto bad; 2235 } 2236 { 2237 /* ip6->ip6_src must be equal to gw for icmp6->icmp6_reddst */ 2238 struct sockaddr_in6 sin6; 2239 struct in6_addr *gw6; 2240 2241 bzero(&sin6, sizeof(sin6)); 2242 sin6.sin6_family = AF_INET6; 2243 sin6.sin6_len = sizeof(struct sockaddr_in6); 2244 bcopy(&reddst6, &sin6.sin6_addr, sizeof reddst6); 2245 rt = rtpurelookup((struct sockaddr *)&sin6); 2246 if (rt != NULL) { 2247 if (rt->rt_gateway == NULL || 2248 rt->rt_gateway->sa_family != AF_INET6) { 2249 nd6log((LOG_ERR, 2250 "ICMP6 redirect rejected; no route " 2251 "with inet6 gateway found for redirect dst: %s\n", 2252 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2253 --rt->rt_refcnt; 2254 goto bad; 2255 } 2256 2257 gw6 = &(((struct sockaddr_in6 *)rt->rt_gateway)->sin6_addr); 2258 if (bcmp(&src6, gw6, sizeof(struct in6_addr)) != 0) { 2259 nd6log((LOG_ERR, 2260 "ICMP6 redirect rejected; " 2261 "not equal to gw-for-src=%s (must be same): " 2262 "%s\n", 2263 ip6_sprintf(gw6), 2264 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2265 --rt->rt_refcnt; 2266 goto bad; 2267 } 2268 } else { 2269 nd6log((LOG_ERR, 2270 "ICMP6 redirect rejected; " 2271 "no route found for redirect dst: %s\n", 2272 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2273 goto bad; 2274 } 2275 --rt->rt_refcnt; 2276 rt = NULL; 2277 } 2278 if (IN6_IS_ADDR_MULTICAST(&reddst6)) { 2279 nd6log((LOG_ERR, 2280 "ICMP6 redirect rejected; " 2281 "redirect dst must be unicast: %s\n", 2282 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2283 goto bad; 2284 } 2285 2286 is_router = is_onlink = 0; 2287 if (IN6_IS_ADDR_LINKLOCAL(&redtgt6)) 2288 is_router = 1; /* router case */ 2289 if (bcmp(&redtgt6, &reddst6, sizeof(redtgt6)) == 0) 2290 is_onlink = 1; /* on-link destination case */ 2291 if (!is_router && !is_onlink) { 2292 nd6log((LOG_ERR, 2293 "ICMP6 redirect rejected; " 2294 "neither router case nor onlink case: %s\n", 2295 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2296 goto bad; 2297 } 2298 /* validation passed */ 2299 2300 icmp6len -= sizeof(*nd_rd); 2301 nd6_option_init(nd_rd + 1, icmp6len, &ndopts); 2302 if (nd6_options(&ndopts) < 0) { 2303 nd6log((LOG_INFO, "icmp6_redirect_input: " 2304 "invalid ND option, rejected: %s\n", 2305 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2306 /* nd6_options have incremented stats */ 2307 goto freeit; 2308 } 2309 2310 if (ndopts.nd_opts_tgt_lladdr) { 2311 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 2312 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 2313 } 2314 2315 if (ndopts.nd_opts_rh) { 2316 redirhdrlen = ndopts.nd_opts_rh->nd_opt_rh_len; 2317 redirhdr = (u_char *)(ndopts.nd_opts_rh + 1); /* xxx */ 2318 } 2319 2320 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 2321 nd6log((LOG_INFO, 2322 "icmp6_redirect_input: lladdrlen mismatch for %s " 2323 "(if %d, icmp6 packet %d): %s\n", 2324 ip6_sprintf(&redtgt6), ifp->if_addrlen, lladdrlen - 2, 2325 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2326 goto bad; 2327 } 2328 2329 /* RFC 2461 8.3 */ 2330 nd6_cache_lladdr(ifp, &redtgt6, lladdr, lladdrlen, ND_REDIRECT, 2331 is_onlink ? ND_REDIRECT_ONLINK : ND_REDIRECT_ROUTER); 2332 2333 if (!is_onlink) { /* better router case. perform rtredirect. */ 2334 /* perform rtredirect */ 2335 struct sockaddr_in6 sdst; 2336 struct sockaddr_in6 sgw; 2337 struct sockaddr_in6 ssrc; 2338 2339 bzero(&sdst, sizeof(sdst)); 2340 bzero(&sgw, sizeof(sgw)); 2341 bzero(&ssrc, sizeof(ssrc)); 2342 sdst.sin6_family = sgw.sin6_family = ssrc.sin6_family = AF_INET6; 2343 sdst.sin6_len = sgw.sin6_len = ssrc.sin6_len = 2344 sizeof(struct sockaddr_in6); 2345 bcopy(&redtgt6, &sgw.sin6_addr, sizeof(struct in6_addr)); 2346 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2347 bcopy(&src6, &ssrc.sin6_addr, sizeof(struct in6_addr)); 2348 rtredirect((struct sockaddr *)&sdst, (struct sockaddr *)&sgw, 2349 (struct sockaddr *)NULL, RTF_GATEWAY | RTF_HOST, 2350 (struct sockaddr *)&ssrc); 2351 } 2352 /* finally update cached route in each socket via pfctlinput */ 2353 { 2354 struct sockaddr_in6 sdst; 2355 2356 bzero(&sdst, sizeof(sdst)); 2357 sdst.sin6_family = AF_INET6; 2358 sdst.sin6_len = sizeof(struct sockaddr_in6); 2359 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2360 pfctlinput(PRC_REDIRECT_HOST, (struct sockaddr *)&sdst); 2361 #ifdef IPSEC 2362 key_sa_routechange((struct sockaddr *)&sdst); 2363 #endif 2364 } 2365 2366 freeit: 2367 m_freem(m); 2368 return; 2369 2370 bad: 2371 icmp6stat.icp6s_badredirect++; 2372 m_freem(m); 2373 } 2374 2375 void 2376 icmp6_redirect_output(struct mbuf *m0, struct rtentry *rt) 2377 { 2378 struct ifnet *ifp; /* my outgoing interface */ 2379 struct in6_addr *ifp_ll6; 2380 struct in6_addr *router_ll6; 2381 struct ip6_hdr *sip6; /* m0 as struct ip6_hdr */ 2382 struct mbuf *m = NULL; /* newly allocated one */ 2383 struct ip6_hdr *ip6; /* m as struct ip6_hdr */ 2384 struct nd_redirect *nd_rd; 2385 size_t maxlen; 2386 u_char *p; 2387 struct ifnet *outif = NULL; 2388 struct sockaddr_in6 src_sa; 2389 2390 icmp6_errcount(&icmp6stat.icp6s_outerrhist, ND_REDIRECT, 0); 2391 2392 /* if we are not router, we don't send icmp6 redirect */ 2393 if (!ip6_forwarding || ip6_accept_rtadv) 2394 goto fail; 2395 2396 /* sanity check */ 2397 if (!m0 || !rt || !(rt->rt_flags & RTF_UP) || !(ifp = rt->rt_ifp)) 2398 goto fail; 2399 2400 /* 2401 * Address check: 2402 * the source address must identify a neighbor, and 2403 * the destination address must not be a multicast address 2404 * [RFC 2461, sec 8.2] 2405 */ 2406 sip6 = mtod(m0, struct ip6_hdr *); 2407 bzero(&src_sa, sizeof(src_sa)); 2408 src_sa.sin6_family = AF_INET6; 2409 src_sa.sin6_len = sizeof(src_sa); 2410 src_sa.sin6_addr = sip6->ip6_src; 2411 /* we don't currently use sin6_scope_id, but eventually use it */ 2412 src_sa.sin6_scope_id = in6_addr2scopeid(ifp, &sip6->ip6_src); 2413 if (nd6_is_addr_neighbor(&src_sa, ifp) == 0) 2414 goto fail; 2415 if (IN6_IS_ADDR_MULTICAST(&sip6->ip6_dst)) 2416 goto fail; /* what should we do here? */ 2417 2418 /* rate limit */ 2419 if (icmp6_ratelimit(&sip6->ip6_src, ND_REDIRECT, 0)) 2420 goto fail; 2421 2422 /* 2423 * Since we are going to append up to 1280 bytes (= IPV6_MMTU), 2424 * we almost always ask for an mbuf cluster for simplicity. 2425 * (MHLEN < IPV6_MMTU is almost always true) 2426 */ 2427 #if IPV6_MMTU >= MCLBYTES 2428 # error assumption failed about IPV6_MMTU and MCLBYTES 2429 #endif 2430 MGETHDR(m, MB_DONTWAIT, MT_HEADER); 2431 if (m && IPV6_MMTU >= MHLEN) 2432 MCLGET(m, MB_DONTWAIT); 2433 if (!m) 2434 goto fail; 2435 m->m_pkthdr.rcvif = NULL; 2436 m->m_len = 0; 2437 maxlen = M_TRAILINGSPACE(m); 2438 maxlen = min(IPV6_MMTU, maxlen); 2439 /* just for safety */ 2440 if (maxlen < sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) + 2441 ((sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7)) { 2442 goto fail; 2443 } 2444 2445 { 2446 /* get ip6 linklocal address for ifp(my outgoing interface). */ 2447 struct in6_ifaddr *ia; 2448 if ((ia = in6ifa_ifpforlinklocal(ifp, 2449 IN6_IFF_NOTREADY| 2450 IN6_IFF_ANYCAST)) == NULL) 2451 goto fail; 2452 ifp_ll6 = &ia->ia_addr.sin6_addr; 2453 } 2454 2455 /* get ip6 linklocal address for the router. */ 2456 if (rt->rt_gateway && (rt->rt_flags & RTF_GATEWAY)) { 2457 struct sockaddr_in6 *sin6; 2458 sin6 = (struct sockaddr_in6 *)rt->rt_gateway; 2459 router_ll6 = &sin6->sin6_addr; 2460 if (!IN6_IS_ADDR_LINKLOCAL(router_ll6)) 2461 router_ll6 = (struct in6_addr *)NULL; 2462 } else 2463 router_ll6 = (struct in6_addr *)NULL; 2464 2465 /* ip6 */ 2466 ip6 = mtod(m, struct ip6_hdr *); 2467 ip6->ip6_flow = 0; 2468 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2469 ip6->ip6_vfc |= IPV6_VERSION; 2470 /* ip6->ip6_plen will be set later */ 2471 ip6->ip6_nxt = IPPROTO_ICMPV6; 2472 ip6->ip6_hlim = 255; 2473 /* ip6->ip6_src must be linklocal addr for my outgoing if. */ 2474 bcopy(ifp_ll6, &ip6->ip6_src, sizeof(struct in6_addr)); 2475 bcopy(&sip6->ip6_src, &ip6->ip6_dst, sizeof(struct in6_addr)); 2476 2477 /* ND Redirect */ 2478 nd_rd = (struct nd_redirect *)(ip6 + 1); 2479 nd_rd->nd_rd_type = ND_REDIRECT; 2480 nd_rd->nd_rd_code = 0; 2481 nd_rd->nd_rd_reserved = 0; 2482 if (rt->rt_flags & RTF_GATEWAY) { 2483 /* 2484 * nd_rd->nd_rd_target must be a link-local address in 2485 * better router cases. 2486 */ 2487 if (!router_ll6) 2488 goto fail; 2489 bcopy(router_ll6, &nd_rd->nd_rd_target, 2490 sizeof(nd_rd->nd_rd_target)); 2491 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2492 sizeof(nd_rd->nd_rd_dst)); 2493 } else { 2494 /* make sure redtgt == reddst */ 2495 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_target, 2496 sizeof(nd_rd->nd_rd_target)); 2497 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2498 sizeof(nd_rd->nd_rd_dst)); 2499 } 2500 2501 p = (u_char *)(nd_rd + 1); 2502 2503 if (!router_ll6) 2504 goto nolladdropt; 2505 2506 { 2507 /* target lladdr option */ 2508 struct rtentry *rt_router = NULL; 2509 int len; 2510 struct sockaddr_dl *sdl; 2511 struct nd_opt_hdr *nd_opt; 2512 char *lladdr; 2513 2514 rt_router = nd6_lookup(router_ll6, 0, ifp); 2515 if (!rt_router) 2516 goto nolladdropt; 2517 len = sizeof(*nd_opt) + ifp->if_addrlen; 2518 len = (len + 7) & ~7; /* round by 8 */ 2519 /* safety check */ 2520 if (len + (p - (u_char *)ip6) > maxlen) 2521 goto nolladdropt; 2522 if (!(rt_router->rt_flags & RTF_GATEWAY) && 2523 (rt_router->rt_flags & RTF_LLINFO) && 2524 (rt_router->rt_gateway->sa_family == AF_LINK) && 2525 (sdl = (struct sockaddr_dl *)rt_router->rt_gateway) && 2526 sdl->sdl_alen) { 2527 nd_opt = (struct nd_opt_hdr *)p; 2528 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 2529 nd_opt->nd_opt_len = len >> 3; 2530 lladdr = (char *)(nd_opt + 1); 2531 bcopy(LLADDR(sdl), lladdr, ifp->if_addrlen); 2532 p += len; 2533 } 2534 } 2535 nolladdropt:; 2536 2537 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2538 2539 /* just to be safe */ 2540 #ifdef M_DECRYPTED /*not openbsd*/ 2541 if (m0->m_flags & M_DECRYPTED) 2542 goto noredhdropt; 2543 #endif 2544 if (p - (u_char *)ip6 > maxlen) 2545 goto noredhdropt; 2546 2547 { 2548 /* redirected header option */ 2549 int len; 2550 struct nd_opt_rd_hdr *nd_opt_rh; 2551 2552 /* 2553 * compute the maximum size for icmp6 redirect header option. 2554 * XXX room for auth header? 2555 */ 2556 len = maxlen - (p - (u_char *)ip6); 2557 len &= ~7; 2558 2559 /* This is just for simplicity. */ 2560 if (m0->m_pkthdr.len != m0->m_len) { 2561 if (m0->m_next) { 2562 m_freem(m0->m_next); 2563 m0->m_next = NULL; 2564 } 2565 m0->m_pkthdr.len = m0->m_len; 2566 } 2567 2568 /* 2569 * Redirected header option spec (RFC2461 4.6.3) talks nothing 2570 * about padding/truncate rule for the original IP packet. 2571 * From the discussion on IPv6imp in Feb 1999, the consensus was: 2572 * - "attach as much as possible" is the goal 2573 * - pad if not aligned (original size can be guessed by original 2574 * ip6 header) 2575 * Following code adds the padding if it is simple enough, 2576 * and truncates if not. 2577 */ 2578 if (m0->m_next || m0->m_pkthdr.len != m0->m_len) 2579 panic("assumption failed in %s:%d", __FILE__, __LINE__); 2580 2581 if (len - sizeof(*nd_opt_rh) < m0->m_pkthdr.len) { 2582 /* not enough room, truncate */ 2583 m0->m_pkthdr.len = m0->m_len = len - sizeof(*nd_opt_rh); 2584 } else { 2585 /* enough room, pad or truncate */ 2586 size_t extra; 2587 2588 extra = m0->m_pkthdr.len % 8; 2589 if (extra) { 2590 /* pad if easy enough, truncate if not */ 2591 if (8 - extra <= M_TRAILINGSPACE(m0)) { 2592 /* pad */ 2593 m0->m_len += (8 - extra); 2594 m0->m_pkthdr.len += (8 - extra); 2595 } else { 2596 /* truncate */ 2597 m0->m_pkthdr.len -= extra; 2598 m0->m_len -= extra; 2599 } 2600 } 2601 len = m0->m_pkthdr.len + sizeof(*nd_opt_rh); 2602 m0->m_pkthdr.len = m0->m_len = len - sizeof(*nd_opt_rh); 2603 } 2604 2605 nd_opt_rh = (struct nd_opt_rd_hdr *)p; 2606 bzero(nd_opt_rh, sizeof(*nd_opt_rh)); 2607 nd_opt_rh->nd_opt_rh_type = ND_OPT_REDIRECTED_HEADER; 2608 nd_opt_rh->nd_opt_rh_len = len >> 3; 2609 p += sizeof(*nd_opt_rh); 2610 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2611 2612 /* connect m0 to m */ 2613 m->m_next = m0; 2614 m->m_pkthdr.len = m->m_len + m0->m_len; 2615 } 2616 noredhdropt:; 2617 2618 if (IN6_IS_ADDR_LINKLOCAL(&sip6->ip6_src)) 2619 sip6->ip6_src.s6_addr16[1] = 0; 2620 if (IN6_IS_ADDR_LINKLOCAL(&sip6->ip6_dst)) 2621 sip6->ip6_dst.s6_addr16[1] = 0; 2622 #if 0 2623 if (IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_src)) 2624 ip6->ip6_src.s6_addr16[1] = 0; 2625 if (IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_dst)) 2626 ip6->ip6_dst.s6_addr16[1] = 0; 2627 #endif 2628 if (IN6_IS_ADDR_LINKLOCAL(&nd_rd->nd_rd_target)) 2629 nd_rd->nd_rd_target.s6_addr16[1] = 0; 2630 if (IN6_IS_ADDR_LINKLOCAL(&nd_rd->nd_rd_dst)) 2631 nd_rd->nd_rd_dst.s6_addr16[1] = 0; 2632 2633 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr)); 2634 2635 nd_rd->nd_rd_cksum = 0; 2636 nd_rd->nd_rd_cksum 2637 = in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), ntohs(ip6->ip6_plen)); 2638 2639 /* send the packet to outside... */ 2640 ip6_output(m, NULL, NULL, 0, NULL, &outif, NULL); 2641 if (outif) { 2642 icmp6_ifstat_inc(outif, ifs6_out_msg); 2643 icmp6_ifstat_inc(outif, ifs6_out_redirect); 2644 } 2645 icmp6stat.icp6s_outhist[ND_REDIRECT]++; 2646 2647 return; 2648 2649 fail: 2650 if (m) 2651 m_freem(m); 2652 if (m0) 2653 m_freem(m0); 2654 } 2655 2656 #ifdef HAVE_NRL_INPCB 2657 #define in6pcb inpcb 2658 #define in6p_icmp6filt inp_icmp6filt 2659 #endif 2660 /* 2661 * ICMPv6 socket option processing. 2662 */ 2663 int 2664 icmp6_ctloutput(struct socket *so, struct sockopt *sopt) 2665 { 2666 int error = 0; 2667 int optlen; 2668 struct inpcb *inp = so->so_pcb; 2669 int level, op, optname; 2670 2671 if (sopt) { 2672 level = sopt->sopt_level; 2673 op = sopt->sopt_dir; 2674 optname = sopt->sopt_name; 2675 optlen = sopt->sopt_valsize; 2676 } else 2677 level = op = optname = optlen = 0; 2678 2679 if (level != IPPROTO_ICMPV6) { 2680 return EINVAL; 2681 } 2682 2683 switch (op) { 2684 case PRCO_SETOPT: 2685 switch (optname) { 2686 case ICMP6_FILTER: 2687 { 2688 struct icmp6_filter *p; 2689 2690 if (optlen != sizeof(*p)) { 2691 error = EMSGSIZE; 2692 break; 2693 } 2694 if (inp->in6p_icmp6filt == NULL) { 2695 error = EINVAL; 2696 break; 2697 } 2698 error = sooptcopyin(sopt, inp->in6p_icmp6filt, optlen, 2699 optlen); 2700 break; 2701 } 2702 2703 default: 2704 error = ENOPROTOOPT; 2705 break; 2706 } 2707 break; 2708 2709 case PRCO_GETOPT: 2710 switch (optname) { 2711 case ICMP6_FILTER: 2712 { 2713 if (inp->in6p_icmp6filt == NULL) { 2714 error = EINVAL; 2715 break; 2716 } 2717 error = sooptcopyout(sopt, inp->in6p_icmp6filt, 2718 sizeof(struct icmp6_filter)); 2719 break; 2720 } 2721 2722 default: 2723 error = ENOPROTOOPT; 2724 break; 2725 } 2726 break; 2727 } 2728 2729 return(error); 2730 } 2731 #ifdef HAVE_NRL_INPCB 2732 #undef in6pcb 2733 #undef in6p_icmp6filt 2734 #endif 2735 2736 #ifndef HAVE_PPSRATECHECK 2737 #ifndef timersub 2738 #define timersub(tvp, uvp, vvp) \ 2739 do { \ 2740 (vvp)->tv_sec = (tvp)->tv_sec - (uvp)->tv_sec; \ 2741 (vvp)->tv_usec = (tvp)->tv_usec - (uvp)->tv_usec; \ 2742 if ((vvp)->tv_usec < 0) { \ 2743 (vvp)->tv_sec--; \ 2744 (vvp)->tv_usec += 1000000; \ 2745 } \ 2746 } while (0) 2747 #endif 2748 2749 /* 2750 * ppsratecheck(): packets (or events) per second limitation. 2751 */ 2752 static int 2753 ppsratecheck(struct timeval *lasttime, int *curpps, 2754 int maxpps) /* maximum pps allowed */ 2755 { 2756 struct timeval tv, delta; 2757 int rv; 2758 2759 microtime(&tv); 2760 2761 timersub(&tv, lasttime, &delta); 2762 2763 /* 2764 * Check for 0,0 so that the message will be seen at least once. 2765 * If more than one second has passed since the last update of 2766 * lasttime, reset the counter. 2767 * 2768 * We do increment *curpps even in *curpps < maxpps case, as some may 2769 * try to use *curpps for stat purposes as well. 2770 */ 2771 if ((lasttime->tv_sec == 0 && lasttime->tv_usec == 0) || 2772 delta.tv_sec >= 1) { 2773 *lasttime = tv; 2774 *curpps = 0; 2775 rv = 1; 2776 } else if (maxpps < 0) 2777 rv = 1; 2778 else if (*curpps < maxpps) 2779 rv = 1; 2780 else 2781 rv = 0; 2782 2783 #if 1 /* DIAGNOSTIC? */ 2784 /* be careful about wrap-around */ 2785 if (*curpps + 1 > *curpps) 2786 *curpps = *curpps + 1; 2787 #else 2788 /* 2789 * assume that there's not too many calls to this function. 2790 * not sure if the assumption holds, as it depends on *caller's* 2791 * behavior, not the behavior of this function. 2792 * IMHO it is wrong to make assumption on the caller's behavior, 2793 * so the above #if is #if 1, not #ifdef DIAGNOSTIC. 2794 */ 2795 *curpps = *curpps + 1; 2796 #endif 2797 2798 return (rv); 2799 } 2800 #endif 2801 2802 /* 2803 * Perform rate limit check. 2804 * Returns 0 if it is okay to send the icmp6 packet. 2805 * Returns 1 if the router SHOULD NOT send this icmp6 packet due to rate 2806 * limitation. 2807 * 2808 * XXX per-destination/type check necessary? 2809 */ 2810 static int 2811 icmp6_ratelimit(const struct in6_addr *dst, /* not used at this moment */ 2812 const int type, /* not used at this moment */ 2813 const int code) /* not used at this moment */ 2814 { 2815 int ret; 2816 2817 ret = 0; /* okay to send */ 2818 2819 /* PPS limit */ 2820 if (!ppsratecheck(&icmp6errppslim_last, &icmp6errpps_count, 2821 icmp6errppslim)) { 2822 /* The packet is subject to rate limit */ 2823 ret++; 2824 } 2825 2826 return ret; 2827 } 2828