1 /* $FreeBSD$ */ 2 /* $KAME: icmp6.c,v 1.211 2001/04/04 05:56:20 itojun Exp $ */ 3 4 /* 5 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the project nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33 /* 34 * Copyright (c) 1982, 1986, 1988, 1993 35 * The Regents of the University of California. All rights reserved. 36 * 37 * Redistribution and use in source and binary forms, with or without 38 * modification, are permitted provided that the following conditions 39 * are met: 40 * 1. Redistributions of source code must retain the above copyright 41 * notice, this list of conditions and the following disclaimer. 42 * 2. Redistributions in binary form must reproduce the above copyright 43 * notice, this list of conditions and the following disclaimer in the 44 * documentation and/or other materials provided with the distribution. 45 * 3. All advertising materials mentioning features or use of this software 46 * must display the following acknowledgement: 47 * This product includes software developed by the University of 48 * California, Berkeley and its contributors. 49 * 4. Neither the name of the University nor the names of its contributors 50 * may be used to endorse or promote products derived from this software 51 * without specific prior written permission. 52 * 53 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 54 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 55 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 56 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 57 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 58 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 59 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 60 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 61 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 62 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 63 * SUCH DAMAGE. 64 * 65 * @(#)ip_icmp.c 8.2 (Berkeley) 1/4/94 66 */ 67 68 #include "opt_inet.h" 69 #include "opt_inet6.h" 70 #include "opt_ipsec.h" 71 72 #include <sys/param.h> 73 #include <sys/systm.h> 74 #include <sys/malloc.h> 75 #include <sys/mbuf.h> 76 #include <sys/protosw.h> 77 #include <sys/socket.h> 78 #include <sys/socketvar.h> 79 #include <sys/time.h> 80 #include <sys/kernel.h> 81 #include <sys/syslog.h> 82 #include <sys/domain.h> 83 84 #include <net/if.h> 85 #include <net/route.h> 86 #include <net/if_dl.h> 87 #include <net/if_types.h> 88 89 #include <netinet/in.h> 90 #include <netinet/in_var.h> 91 #include <netinet/ip6.h> 92 #include <netinet6/ip6_var.h> 93 #include <netinet/icmp6.h> 94 #include <netinet6/mld6_var.h> 95 #include <netinet/in_pcb.h> 96 #include <netinet6/in6_pcb.h> 97 #include <netinet6/nd6.h> 98 #include <netinet6/in6_ifattach.h> 99 #include <netinet6/ip6protosw.h> 100 101 #ifdef IPSEC 102 #include <netinet6/ipsec.h> 103 #include <netkey/key.h> 104 #endif 105 106 #include <net/net_osdep.h> 107 108 #ifdef HAVE_NRL_INPCB 109 /* inpcb members */ 110 #define in6pcb inpcb 111 #define in6p_laddr inp_laddr6 112 #define in6p_faddr inp_faddr6 113 #define in6p_icmp6filt inp_icmp6filt 114 #define in6p_route inp_route 115 #define in6p_socket inp_socket 116 #define in6p_flags inp_flags 117 #define in6p_moptions inp_moptions6 118 #define in6p_outputopts inp_outputopts6 119 #define in6p_ip6 inp_ipv6 120 #define in6p_flowinfo inp_flowinfo 121 #define in6p_sp inp_sp 122 #define in6p_next inp_next 123 #define in6p_prev inp_prev 124 /* macro names */ 125 #define sotoin6pcb sotoinpcb 126 /* function names */ 127 #define in6_pcbdetach in_pcbdetach 128 #define in6_rtchange in_rtchange 129 130 /* 131 * for KAME src sync over BSD*'s. XXX: FreeBSD (>=3) are VERY different from 132 * others... 133 */ 134 #define in6p_ip6_nxt inp_ipv6.ip6_nxt 135 #endif 136 137 extern struct domain inet6domain; 138 extern struct ip6protosw inet6sw[]; 139 extern u_char ip6_protox[]; 140 141 struct icmp6stat icmp6stat; 142 143 extern struct inpcbhead ripcb; 144 extern int icmp6errppslim; 145 static int icmp6errpps_count = 0; 146 static struct timeval icmp6errppslim_last; 147 extern int icmp6_nodeinfo; 148 149 static void icmp6_errcount __P((struct icmp6errstat *, int, int)); 150 static int icmp6_rip6_input __P((struct mbuf **, int)); 151 static int icmp6_ratelimit __P((const struct in6_addr *, const int, const int)); 152 static const char *icmp6_redirect_diag __P((struct in6_addr *, 153 struct in6_addr *, struct in6_addr *)); 154 #ifndef HAVE_PPSRATECHECK 155 static int ppsratecheck __P((struct timeval *, int *, int)); 156 #endif 157 static struct mbuf *ni6_input __P((struct mbuf *, int)); 158 static struct mbuf *ni6_nametodns __P((const char *, int, int)); 159 static int ni6_dnsmatch __P((const char *, int, const char *, int)); 160 static int ni6_addrs __P((struct icmp6_nodeinfo *, struct mbuf *, 161 struct ifnet **, char *)); 162 static int ni6_store_addrs __P((struct icmp6_nodeinfo *, struct icmp6_nodeinfo *, 163 struct ifnet *, int)); 164 static int icmp6_notify_error __P((struct mbuf *, int, int, int)); 165 166 #ifdef COMPAT_RFC1885 167 static struct route_in6 icmp6_reflect_rt; 168 #endif 169 170 171 void 172 icmp6_init() 173 { 174 mld6_init(); 175 } 176 177 static void 178 icmp6_errcount(stat, type, code) 179 struct icmp6errstat *stat; 180 int type, code; 181 { 182 switch (type) { 183 case ICMP6_DST_UNREACH: 184 switch (code) { 185 case ICMP6_DST_UNREACH_NOROUTE: 186 stat->icp6errs_dst_unreach_noroute++; 187 return; 188 case ICMP6_DST_UNREACH_ADMIN: 189 stat->icp6errs_dst_unreach_admin++; 190 return; 191 case ICMP6_DST_UNREACH_BEYONDSCOPE: 192 stat->icp6errs_dst_unreach_beyondscope++; 193 return; 194 case ICMP6_DST_UNREACH_ADDR: 195 stat->icp6errs_dst_unreach_addr++; 196 return; 197 case ICMP6_DST_UNREACH_NOPORT: 198 stat->icp6errs_dst_unreach_noport++; 199 return; 200 } 201 break; 202 case ICMP6_PACKET_TOO_BIG: 203 stat->icp6errs_packet_too_big++; 204 return; 205 case ICMP6_TIME_EXCEEDED: 206 switch (code) { 207 case ICMP6_TIME_EXCEED_TRANSIT: 208 stat->icp6errs_time_exceed_transit++; 209 return; 210 case ICMP6_TIME_EXCEED_REASSEMBLY: 211 stat->icp6errs_time_exceed_reassembly++; 212 return; 213 } 214 break; 215 case ICMP6_PARAM_PROB: 216 switch (code) { 217 case ICMP6_PARAMPROB_HEADER: 218 stat->icp6errs_paramprob_header++; 219 return; 220 case ICMP6_PARAMPROB_NEXTHEADER: 221 stat->icp6errs_paramprob_nextheader++; 222 return; 223 case ICMP6_PARAMPROB_OPTION: 224 stat->icp6errs_paramprob_option++; 225 return; 226 } 227 break; 228 case ND_REDIRECT: 229 stat->icp6errs_redirect++; 230 return; 231 } 232 stat->icp6errs_unknown++; 233 } 234 235 /* 236 * Generate an error packet of type error in response to bad IP6 packet. 237 */ 238 void 239 icmp6_error(m, type, code, param) 240 struct mbuf *m; 241 int type, code, param; 242 { 243 struct ip6_hdr *oip6, *nip6; 244 struct icmp6_hdr *icmp6; 245 u_int preplen; 246 int off; 247 int nxt; 248 249 icmp6stat.icp6s_error++; 250 251 /* count per-type-code statistics */ 252 icmp6_errcount(&icmp6stat.icp6s_outerrhist, type, code); 253 254 #ifdef M_DECRYPTED /*not openbsd*/ 255 if (m->m_flags & M_DECRYPTED) { 256 icmp6stat.icp6s_canterror++; 257 goto freeit; 258 } 259 #endif 260 261 #ifndef PULLDOWN_TEST 262 IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), ); 263 #else 264 if (m->m_len < sizeof(struct ip6_hdr)) { 265 m = m_pullup(m, sizeof(struct ip6_hdr)); 266 if (m == NULL) 267 return; 268 } 269 #endif 270 oip6 = mtod(m, struct ip6_hdr *); 271 272 /* 273 * Multicast destination check. For unrecognized option errors, 274 * this check has already done in ip6_unknown_opt(), so we can 275 * check only for other errors. 276 */ 277 if ((m->m_flags & (M_BCAST|M_MCAST) || 278 IN6_IS_ADDR_MULTICAST(&oip6->ip6_dst)) && 279 (type != ICMP6_PACKET_TOO_BIG && 280 (type != ICMP6_PARAM_PROB || 281 code != ICMP6_PARAMPROB_OPTION))) 282 goto freeit; 283 284 /* Source address check. XXX: the case of anycast source? */ 285 if (IN6_IS_ADDR_UNSPECIFIED(&oip6->ip6_src) || 286 IN6_IS_ADDR_MULTICAST(&oip6->ip6_src)) 287 goto freeit; 288 289 /* 290 * If we are about to send ICMPv6 against ICMPv6 error/redirect, 291 * don't do it. 292 */ 293 nxt = -1; 294 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); 295 if (off >= 0 && nxt == IPPROTO_ICMPV6) { 296 struct icmp6_hdr *icp; 297 298 #ifndef PULLDOWN_TEST 299 IP6_EXTHDR_CHECK(m, 0, off + sizeof(struct icmp6_hdr), ); 300 icp = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 301 #else 302 IP6_EXTHDR_GET(icp, struct icmp6_hdr *, m, off, 303 sizeof(*icp)); 304 if (icp == NULL) { 305 icmp6stat.icp6s_tooshort++; 306 return; 307 } 308 #endif 309 if (icp->icmp6_type < ICMP6_ECHO_REQUEST || 310 icp->icmp6_type == ND_REDIRECT) { 311 /* 312 * ICMPv6 error 313 * Special case: for redirect (which is 314 * informational) we must not send icmp6 error. 315 */ 316 icmp6stat.icp6s_canterror++; 317 goto freeit; 318 } else { 319 /* ICMPv6 informational - send the error */ 320 } 321 } else { 322 /* non-ICMPv6 - send the error */ 323 } 324 325 oip6 = mtod(m, struct ip6_hdr *); /* adjust pointer */ 326 327 /* Finally, do rate limitation check. */ 328 if (icmp6_ratelimit(&oip6->ip6_src, type, code)) { 329 icmp6stat.icp6s_toofreq++; 330 goto freeit; 331 } 332 333 /* 334 * OK, ICMP6 can be generated. 335 */ 336 337 if (m->m_pkthdr.len >= ICMPV6_PLD_MAXLEN) 338 m_adj(m, ICMPV6_PLD_MAXLEN - m->m_pkthdr.len); 339 340 preplen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 341 M_PREPEND(m, preplen, M_DONTWAIT); 342 if (m && m->m_len < preplen) 343 m = m_pullup(m, preplen); 344 if (m == NULL) { 345 nd6log((LOG_DEBUG, "ENOBUFS in icmp6_error %d\n", __LINE__)); 346 return; 347 } 348 349 nip6 = mtod(m, struct ip6_hdr *); 350 nip6->ip6_src = oip6->ip6_src; 351 nip6->ip6_dst = oip6->ip6_dst; 352 353 if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_src)) 354 oip6->ip6_src.s6_addr16[1] = 0; 355 if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_dst)) 356 oip6->ip6_dst.s6_addr16[1] = 0; 357 358 icmp6 = (struct icmp6_hdr *)(nip6 + 1); 359 icmp6->icmp6_type = type; 360 icmp6->icmp6_code = code; 361 icmp6->icmp6_pptr = htonl((u_int32_t)param); 362 363 /* 364 * icmp6_reflect() is designed to be in the input path. 365 * icmp6_error() can be called from both input and outut path, 366 * and if we are in output path rcvif could contain bogus value. 367 * clear m->m_pkthdr.rcvif for safety, we should have enough scope 368 * information in ip header (nip6). 369 */ 370 m->m_pkthdr.rcvif = NULL; 371 372 icmp6stat.icp6s_outhist[type]++; 373 icmp6_reflect(m, sizeof(struct ip6_hdr)); /*header order: IPv6 - ICMPv6*/ 374 375 return; 376 377 freeit: 378 /* 379 * If we can't tell wheter or not we can generate ICMP6, free it. 380 */ 381 m_freem(m); 382 } 383 384 /* 385 * Process a received ICMP6 message. 386 */ 387 int 388 icmp6_input(mp, offp, proto) 389 struct mbuf **mp; 390 int *offp, proto; 391 { 392 struct mbuf *m = *mp, *n; 393 struct ip6_hdr *ip6, *nip6; 394 struct icmp6_hdr *icmp6, *nicmp6; 395 int off = *offp; 396 int icmp6len = m->m_pkthdr.len - *offp; 397 int code, sum, noff; 398 399 #ifndef PULLDOWN_TEST 400 IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_hdr), IPPROTO_DONE); 401 /* m might change if M_LOOP. So, call mtod after this */ 402 #endif 403 404 /* 405 * Locate icmp6 structure in mbuf, and check 406 * that not corrupted and of at least minimum length 407 */ 408 409 ip6 = mtod(m, struct ip6_hdr *); 410 if (icmp6len < sizeof(struct icmp6_hdr)) { 411 icmp6stat.icp6s_tooshort++; 412 goto freeit; 413 } 414 415 /* 416 * calculate the checksum 417 */ 418 #ifndef PULLDOWN_TEST 419 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off); 420 #else 421 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 422 if (icmp6 == NULL) { 423 icmp6stat.icp6s_tooshort++; 424 return IPPROTO_DONE; 425 } 426 #endif 427 code = icmp6->icmp6_code; 428 429 if ((sum = in6_cksum(m, IPPROTO_ICMPV6, off, icmp6len)) != 0) { 430 nd6log((LOG_ERR, 431 "ICMP6 checksum error(%d|%x) %s\n", 432 icmp6->icmp6_type, sum, ip6_sprintf(&ip6->ip6_src))); 433 icmp6stat.icp6s_checksum++; 434 goto freeit; 435 } 436 437 if (faithprefix_p != NULL && (*faithprefix_p)(&ip6->ip6_dst)) { 438 /* 439 * Deliver very specific ICMP6 type only. 440 * This is important to deilver TOOBIG. Otherwise PMTUD 441 * will not work. 442 */ 443 switch (icmp6->icmp6_type) { 444 case ICMP6_DST_UNREACH: 445 case ICMP6_PACKET_TOO_BIG: 446 case ICMP6_TIME_EXCEEDED: 447 break; 448 default: 449 goto freeit; 450 } 451 } 452 453 icmp6stat.icp6s_inhist[icmp6->icmp6_type]++; 454 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_msg); 455 if (icmp6->icmp6_type < ICMP6_INFOMSG_MASK) 456 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_error); 457 458 switch (icmp6->icmp6_type) { 459 case ICMP6_DST_UNREACH: 460 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_dstunreach); 461 switch (code) { 462 case ICMP6_DST_UNREACH_NOROUTE: 463 code = PRC_UNREACH_NET; 464 break; 465 case ICMP6_DST_UNREACH_ADMIN: 466 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_adminprohib); 467 code = PRC_UNREACH_PROTOCOL; /* is this a good code? */ 468 break; 469 case ICMP6_DST_UNREACH_ADDR: 470 code = PRC_HOSTDEAD; 471 break; 472 #ifdef COMPAT_RFC1885 473 case ICMP6_DST_UNREACH_NOTNEIGHBOR: 474 code = PRC_UNREACH_SRCFAIL; 475 break; 476 #else 477 case ICMP6_DST_UNREACH_BEYONDSCOPE: 478 /* I mean "source address was incorrect." */ 479 code = PRC_PARAMPROB; 480 break; 481 #endif 482 case ICMP6_DST_UNREACH_NOPORT: 483 code = PRC_UNREACH_PORT; 484 break; 485 default: 486 goto badcode; 487 } 488 goto deliver; 489 break; 490 491 case ICMP6_PACKET_TOO_BIG: 492 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_pkttoobig); 493 if (code != 0) 494 goto badcode; 495 496 code = PRC_MSGSIZE; 497 498 /* 499 * Updating the path MTU will be done after examining 500 * intermediate extension headers. 501 */ 502 goto deliver; 503 break; 504 505 case ICMP6_TIME_EXCEEDED: 506 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_timeexceed); 507 switch (code) { 508 case ICMP6_TIME_EXCEED_TRANSIT: 509 case ICMP6_TIME_EXCEED_REASSEMBLY: 510 code += PRC_TIMXCEED_INTRANS; 511 break; 512 default: 513 goto badcode; 514 } 515 goto deliver; 516 break; 517 518 case ICMP6_PARAM_PROB: 519 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_paramprob); 520 switch (code) { 521 case ICMP6_PARAMPROB_NEXTHEADER: 522 code = PRC_UNREACH_PROTOCOL; 523 break; 524 case ICMP6_PARAMPROB_HEADER: 525 case ICMP6_PARAMPROB_OPTION: 526 code = PRC_PARAMPROB; 527 break; 528 default: 529 goto badcode; 530 } 531 goto deliver; 532 break; 533 534 case ICMP6_ECHO_REQUEST: 535 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echo); 536 if (code != 0) 537 goto badcode; 538 if ((n = m_copy(m, 0, M_COPYALL)) == NULL) { 539 /* Give up remote */ 540 break; 541 } 542 if ((n->m_flags & M_EXT) != 0 543 || n->m_len < off + sizeof(struct icmp6_hdr)) { 544 struct mbuf *n0 = n; 545 const int maxlen = sizeof(*nip6) + sizeof(*nicmp6); 546 547 /* 548 * Prepare an internal mbuf. m_pullup() doesn't 549 * always copy the length we specified. 550 */ 551 if (maxlen >= MCLBYTES) { 552 /* Give up remote */ 553 m_freem(n0); 554 break; 555 } 556 MGETHDR(n, M_DONTWAIT, n0->m_type); 557 if (n && maxlen >= MHLEN) { 558 MCLGET(n, M_DONTWAIT); 559 if ((n->m_flags & M_EXT) == 0) { 560 m_free(n); 561 n = NULL; 562 } 563 } 564 if (n == NULL) { 565 /* Give up remote */ 566 m_freem(n0); 567 break; 568 } 569 M_COPY_PKTHDR(n, n0); 570 /* 571 * Copy IPv6 and ICMPv6 only. 572 */ 573 nip6 = mtod(n, struct ip6_hdr *); 574 bcopy(ip6, nip6, sizeof(struct ip6_hdr)); 575 nicmp6 = (struct icmp6_hdr *)(nip6 + 1); 576 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr)); 577 noff = sizeof(struct ip6_hdr); 578 n->m_pkthdr.len = n->m_len = 579 noff + sizeof(struct icmp6_hdr); 580 /* 581 * Adjust mbuf. ip6_plen will be adjusted in 582 * ip6_output(). 583 */ 584 m_adj(n0, off + sizeof(struct icmp6_hdr)); 585 n->m_pkthdr.len += n0->m_pkthdr.len; 586 n->m_next = n0; 587 n0->m_flags &= ~M_PKTHDR; 588 } else { 589 nip6 = mtod(n, struct ip6_hdr *); 590 nicmp6 = (struct icmp6_hdr *)((caddr_t)nip6 + off); 591 noff = off; 592 } 593 nicmp6->icmp6_type = ICMP6_ECHO_REPLY; 594 nicmp6->icmp6_code = 0; 595 if (n) { 596 icmp6stat.icp6s_reflect++; 597 icmp6stat.icp6s_outhist[ICMP6_ECHO_REPLY]++; 598 icmp6_reflect(n, noff); 599 } 600 break; 601 602 case ICMP6_ECHO_REPLY: 603 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echoreply); 604 if (code != 0) 605 goto badcode; 606 break; 607 608 case MLD6_LISTENER_QUERY: 609 case MLD6_LISTENER_REPORT: 610 if (icmp6len < sizeof(struct mld6_hdr)) 611 goto badlen; 612 if (icmp6->icmp6_type == MLD6_LISTENER_QUERY) /* XXX: ugly... */ 613 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldquery); 614 else 615 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldreport); 616 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 617 /* give up local */ 618 mld6_input(m, off); 619 m = NULL; 620 goto freeit; 621 } 622 mld6_input(n, off); 623 /* m stays. */ 624 break; 625 626 case MLD6_LISTENER_DONE: 627 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mlddone); 628 if (icmp6len < sizeof(struct mld6_hdr)) /* necessary? */ 629 goto badlen; 630 break; /* nothing to be done in kernel */ 631 632 case MLD6_MTRACE_RESP: 633 case MLD6_MTRACE: 634 /* XXX: these two are experimental. not officially defind. */ 635 /* XXX: per-interface statistics? */ 636 break; /* just pass it to applications */ 637 638 case ICMP6_WRUREQUEST: /* ICMP6_FQDN_QUERY */ 639 { 640 enum { WRU, FQDN } mode; 641 642 if (!icmp6_nodeinfo) 643 break; 644 645 if (icmp6len == sizeof(struct icmp6_hdr) + 4) 646 mode = WRU; 647 else if (icmp6len >= sizeof(struct icmp6_nodeinfo)) 648 mode = FQDN; 649 else 650 goto badlen; 651 652 #define hostnamelen strlen(hostname) 653 if (mode == FQDN) { 654 #ifndef PULLDOWN_TEST 655 IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_nodeinfo), 656 IPPROTO_DONE); 657 #endif 658 n = m_copy(m, 0, M_COPYALL); 659 if (n) 660 n = ni6_input(n, off); 661 /* XXX meaningless if n == NULL */ 662 noff = sizeof(struct ip6_hdr); 663 } else { 664 u_char *p; 665 int maxlen, maxhlen; 666 667 if ((icmp6_nodeinfo & 5) != 5) 668 break; 669 670 if (code != 0) 671 goto badcode; 672 maxlen = sizeof(*nip6) + sizeof(*nicmp6) + 4; 673 if (maxlen >= MCLBYTES) { 674 /* Give up remote */ 675 break; 676 } 677 MGETHDR(n, M_DONTWAIT, m->m_type); 678 if (n && maxlen > MHLEN) { 679 MCLGET(n, M_DONTWAIT); 680 if ((n->m_flags & M_EXT) == 0) { 681 m_free(n); 682 n = NULL; 683 } 684 } 685 if (n == NULL) { 686 /* Give up remote */ 687 break; 688 } 689 n->m_pkthdr.rcvif = NULL; 690 n->m_len = 0; 691 maxhlen = M_TRAILINGSPACE(n) - maxlen; 692 if (maxhlen > hostnamelen) 693 maxhlen = hostnamelen; 694 /* 695 * Copy IPv6 and ICMPv6 only. 696 */ 697 nip6 = mtod(n, struct ip6_hdr *); 698 bcopy(ip6, nip6, sizeof(struct ip6_hdr)); 699 nicmp6 = (struct icmp6_hdr *)(nip6 + 1); 700 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr)); 701 p = (u_char *)(nicmp6 + 1); 702 bzero(p, 4); 703 bcopy(hostname, p + 4, maxhlen); /*meaningless TTL*/ 704 noff = sizeof(struct ip6_hdr); 705 M_COPY_PKTHDR(n, m); /* just for recvif */ 706 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) + 707 sizeof(struct icmp6_hdr) + 4 + maxhlen; 708 nicmp6->icmp6_type = ICMP6_WRUREPLY; 709 nicmp6->icmp6_code = 0; 710 } 711 #undef hostnamelen 712 if (n) { 713 icmp6stat.icp6s_reflect++; 714 icmp6stat.icp6s_outhist[ICMP6_WRUREPLY]++; 715 icmp6_reflect(n, noff); 716 } 717 break; 718 } 719 720 case ICMP6_WRUREPLY: 721 if (code != 0) 722 goto badcode; 723 break; 724 725 case ND_ROUTER_SOLICIT: 726 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routersolicit); 727 if (code != 0) 728 goto badcode; 729 if (icmp6len < sizeof(struct nd_router_solicit)) 730 goto badlen; 731 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 732 /* give up local */ 733 nd6_rs_input(m, off, icmp6len); 734 m = NULL; 735 goto freeit; 736 } 737 nd6_rs_input(n, off, icmp6len); 738 /* m stays. */ 739 break; 740 741 case ND_ROUTER_ADVERT: 742 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routeradvert); 743 if (code != 0) 744 goto badcode; 745 if (icmp6len < sizeof(struct nd_router_advert)) 746 goto badlen; 747 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 748 /* give up local */ 749 nd6_ra_input(m, off, icmp6len); 750 m = NULL; 751 goto freeit; 752 } 753 nd6_ra_input(n, off, icmp6len); 754 /* m stays. */ 755 break; 756 757 case ND_NEIGHBOR_SOLICIT: 758 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighborsolicit); 759 if (code != 0) 760 goto badcode; 761 if (icmp6len < sizeof(struct nd_neighbor_solicit)) 762 goto badlen; 763 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 764 /* give up local */ 765 nd6_ns_input(m, off, icmp6len); 766 m = NULL; 767 goto freeit; 768 } 769 nd6_ns_input(n, off, icmp6len); 770 /* m stays. */ 771 break; 772 773 case ND_NEIGHBOR_ADVERT: 774 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighboradvert); 775 if (code != 0) 776 goto badcode; 777 if (icmp6len < sizeof(struct nd_neighbor_advert)) 778 goto badlen; 779 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 780 /* give up local */ 781 nd6_na_input(m, off, icmp6len); 782 m = NULL; 783 goto freeit; 784 } 785 nd6_na_input(n, off, icmp6len); 786 /* m stays. */ 787 break; 788 789 case ND_REDIRECT: 790 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_redirect); 791 if (code != 0) 792 goto badcode; 793 if (icmp6len < sizeof(struct nd_redirect)) 794 goto badlen; 795 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 796 /* give up local */ 797 icmp6_redirect_input(m, off); 798 m = NULL; 799 goto freeit; 800 } 801 icmp6_redirect_input(n, off); 802 /* m stays. */ 803 break; 804 805 case ICMP6_ROUTER_RENUMBERING: 806 if (code != ICMP6_ROUTER_RENUMBERING_COMMAND && 807 code != ICMP6_ROUTER_RENUMBERING_RESULT) 808 goto badcode; 809 if (icmp6len < sizeof(struct icmp6_router_renum)) 810 goto badlen; 811 break; 812 813 default: 814 nd6log((LOG_DEBUG, 815 "icmp6_input: unknown type %d(src=%s, dst=%s, ifid=%d)\n", 816 icmp6->icmp6_type, ip6_sprintf(&ip6->ip6_src), 817 ip6_sprintf(&ip6->ip6_dst), 818 m->m_pkthdr.rcvif ? m->m_pkthdr.rcvif->if_index : 0)); 819 if (icmp6->icmp6_type < ICMP6_ECHO_REQUEST) { 820 /* ICMPv6 error: MUST deliver it by spec... */ 821 code = PRC_NCMDS; 822 /* deliver */ 823 } else { 824 /* ICMPv6 informational: MUST not deliver */ 825 break; 826 } 827 deliver: 828 if (icmp6_notify_error(m, off, icmp6len, code)) { 829 /* In this case, m should've been freed. */ 830 return(IPPROTO_DONE); 831 } 832 break; 833 834 badcode: 835 icmp6stat.icp6s_badcode++; 836 break; 837 838 badlen: 839 icmp6stat.icp6s_badlen++; 840 break; 841 } 842 843 /* deliver the packet to appropriate sockets */ 844 icmp6_rip6_input(&m, *offp); 845 846 return IPPROTO_DONE; 847 848 freeit: 849 m_freem(m); 850 return IPPROTO_DONE; 851 } 852 853 static int 854 icmp6_notify_error(m, off, icmp6len, code) 855 struct mbuf *m; 856 int off, icmp6len; 857 { 858 struct icmp6_hdr *icmp6; 859 struct ip6_hdr *eip6; 860 u_int32_t notifymtu; 861 struct sockaddr_in6 icmp6src, icmp6dst; 862 863 if (icmp6len < sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr)) { 864 icmp6stat.icp6s_tooshort++; 865 goto freeit; 866 } 867 #ifndef PULLDOWN_TEST 868 IP6_EXTHDR_CHECK(m, off, 869 sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr), 870 -1); 871 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 872 #else 873 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, 874 sizeof(*icmp6) + sizeof(struct ip6_hdr)); 875 if (icmp6 == NULL) { 876 icmp6stat.icp6s_tooshort++; 877 return(-1); 878 } 879 #endif 880 eip6 = (struct ip6_hdr *)(icmp6 + 1); 881 882 /* Detect the upper level protocol */ 883 { 884 void (*ctlfunc) __P((int, struct sockaddr *, void *)); 885 u_int8_t nxt = eip6->ip6_nxt; 886 int eoff = off + sizeof(struct icmp6_hdr) + 887 sizeof(struct ip6_hdr); 888 struct ip6ctlparam ip6cp; 889 struct in6_addr *finaldst = NULL; 890 int icmp6type = icmp6->icmp6_type; 891 struct ip6_frag *fh; 892 struct ip6_rthdr *rth; 893 struct ip6_rthdr0 *rth0; 894 int rthlen; 895 896 while (1) { /* XXX: should avoid inf. loop explicitly? */ 897 struct ip6_ext *eh; 898 899 switch (nxt) { 900 case IPPROTO_HOPOPTS: 901 case IPPROTO_DSTOPTS: 902 case IPPROTO_AH: 903 #ifndef PULLDOWN_TEST 904 IP6_EXTHDR_CHECK(m, 0, eoff + 905 sizeof(struct ip6_ext), 906 -1); 907 eh = (struct ip6_ext *)(mtod(m, caddr_t) 908 + eoff); 909 #else 910 IP6_EXTHDR_GET(eh, struct ip6_ext *, m, 911 eoff, sizeof(*eh)); 912 if (eh == NULL) { 913 icmp6stat.icp6s_tooshort++; 914 return(-1); 915 } 916 #endif 917 918 if (nxt == IPPROTO_AH) 919 eoff += (eh->ip6e_len + 2) << 2; 920 else 921 eoff += (eh->ip6e_len + 1) << 3; 922 nxt = eh->ip6e_nxt; 923 break; 924 case IPPROTO_ROUTING: 925 /* 926 * When the erroneous packet contains a 927 * routing header, we should examine the 928 * header to determine the final destination. 929 * Otherwise, we can't properly update 930 * information that depends on the final 931 * destination (e.g. path MTU). 932 */ 933 #ifndef PULLDOWN_TEST 934 IP6_EXTHDR_CHECK(m, 0, eoff + sizeof(*rth), 935 -1); 936 rth = (struct ip6_rthdr *)(mtod(m, caddr_t) 937 + eoff); 938 #else 939 IP6_EXTHDR_GET(rth, struct ip6_rthdr *, m, 940 eoff, sizeof(*rth)); 941 if (rth == NULL) { 942 icmp6stat.icp6s_tooshort++; 943 return(-1); 944 } 945 #endif 946 rthlen = (rth->ip6r_len + 1) << 3; 947 /* 948 * XXX: currently there is no 949 * officially defined type other 950 * than type-0. 951 * Note that if the segment left field 952 * is 0, all intermediate hops must 953 * have been passed. 954 */ 955 if (rth->ip6r_segleft && 956 rth->ip6r_type == IPV6_RTHDR_TYPE_0) { 957 int hops; 958 959 #ifndef PULLDOWN_TEST 960 IP6_EXTHDR_CHECK(m, 0, eoff + rthlen, 961 -1); 962 rth0 = (struct ip6_rthdr0 *)(mtod(m, caddr_t) + eoff); 963 #else 964 IP6_EXTHDR_GET(rth0, 965 struct ip6_rthdr0 *, m, 966 eoff, rthlen); 967 if (rth0 == NULL) { 968 icmp6stat.icp6s_tooshort++; 969 return(-1); 970 } 971 #endif 972 /* just ignore a bogus header */ 973 if ((rth0->ip6r0_len % 2) == 0 && 974 (hops = rth0->ip6r0_len/2)) 975 finaldst = (struct in6_addr *)(rth0 + 1) + (hops - 1); 976 } 977 eoff += rthlen; 978 nxt = rth->ip6r_nxt; 979 break; 980 case IPPROTO_FRAGMENT: 981 #ifndef PULLDOWN_TEST 982 IP6_EXTHDR_CHECK(m, 0, eoff + 983 sizeof(struct ip6_frag), 984 -1); 985 fh = (struct ip6_frag *)(mtod(m, caddr_t) 986 + eoff); 987 #else 988 IP6_EXTHDR_GET(fh, struct ip6_frag *, m, 989 eoff, sizeof(*fh)); 990 if (fh == NULL) { 991 icmp6stat.icp6s_tooshort++; 992 return(-1); 993 } 994 #endif 995 /* 996 * Data after a fragment header is meaningless 997 * unless it is the first fragment, but 998 * we'll go to the notify label for path MTU 999 * discovery. 1000 */ 1001 if (fh->ip6f_offlg & IP6F_OFF_MASK) 1002 goto notify; 1003 1004 eoff += sizeof(struct ip6_frag); 1005 nxt = fh->ip6f_nxt; 1006 break; 1007 default: 1008 /* 1009 * This case includes ESP and the No Next 1010 * Header. In such cases going to the notify 1011 * label does not have any meaning 1012 * (i.e. ctlfunc will be NULL), but we go 1013 * anyway since we might have to update 1014 * path MTU information. 1015 */ 1016 goto notify; 1017 } 1018 } 1019 notify: 1020 #ifndef PULLDOWN_TEST 1021 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 1022 #else 1023 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, 1024 sizeof(*icmp6) + sizeof(struct ip6_hdr)); 1025 if (icmp6 == NULL) { 1026 icmp6stat.icp6s_tooshort++; 1027 return(-1); 1028 } 1029 #endif 1030 1031 eip6 = (struct ip6_hdr *)(icmp6 + 1); 1032 bzero(&icmp6dst, sizeof(icmp6dst)); 1033 icmp6dst.sin6_len = sizeof(struct sockaddr_in6); 1034 icmp6dst.sin6_family = AF_INET6; 1035 if (finaldst == NULL) 1036 icmp6dst.sin6_addr = eip6->ip6_dst; 1037 else 1038 icmp6dst.sin6_addr = *finaldst; 1039 icmp6dst.sin6_scope_id = in6_addr2scopeid(m->m_pkthdr.rcvif, 1040 &icmp6dst.sin6_addr); 1041 #ifndef SCOPEDROUTING 1042 if (in6_embedscope(&icmp6dst.sin6_addr, &icmp6dst, 1043 NULL, NULL)) { 1044 /* should be impossbile */ 1045 nd6log((LOG_DEBUG, 1046 "icmp6_notify_error: in6_embedscope failed\n")); 1047 goto freeit; 1048 } 1049 #endif 1050 1051 /* 1052 * retrieve parameters from the inner IPv6 header, and convert 1053 * them into sockaddr structures. 1054 */ 1055 bzero(&icmp6src, sizeof(icmp6src)); 1056 icmp6src.sin6_len = sizeof(struct sockaddr_in6); 1057 icmp6src.sin6_family = AF_INET6; 1058 icmp6src.sin6_addr = eip6->ip6_src; 1059 icmp6src.sin6_scope_id = in6_addr2scopeid(m->m_pkthdr.rcvif, 1060 &icmp6src.sin6_addr); 1061 #ifndef SCOPEDROUTING 1062 if (in6_embedscope(&icmp6src.sin6_addr, &icmp6src, 1063 NULL, NULL)) { 1064 /* should be impossbile */ 1065 nd6log((LOG_DEBUG, 1066 "icmp6_notify_error: in6_embedscope failed\n")); 1067 goto freeit; 1068 } 1069 #endif 1070 icmp6src.sin6_flowinfo = 1071 (eip6->ip6_flow & IPV6_FLOWLABEL_MASK); 1072 1073 if (finaldst == NULL) 1074 finaldst = &eip6->ip6_dst; 1075 ip6cp.ip6c_m = m; 1076 ip6cp.ip6c_icmp6 = icmp6; 1077 ip6cp.ip6c_ip6 = (struct ip6_hdr *)(icmp6 + 1); 1078 ip6cp.ip6c_off = eoff; 1079 ip6cp.ip6c_finaldst = finaldst; 1080 ip6cp.ip6c_src = &icmp6src; 1081 ip6cp.ip6c_nxt = nxt; 1082 1083 if (icmp6type == ICMP6_PACKET_TOO_BIG) { 1084 notifymtu = ntohl(icmp6->icmp6_mtu); 1085 ip6cp.ip6c_cmdarg = (void *)¬ifymtu; 1086 icmp6_mtudisc_update(&ip6cp, 1); /*XXX*/ 1087 } 1088 1089 ctlfunc = (void (*) __P((int, struct sockaddr *, void *))) 1090 (inet6sw[ip6_protox[nxt]].pr_ctlinput); 1091 if (ctlfunc) { 1092 (void) (*ctlfunc)(code, (struct sockaddr *)&icmp6dst, 1093 &ip6cp); 1094 } 1095 } 1096 return(0); 1097 1098 freeit: 1099 m_freem(m); 1100 return(-1); 1101 } 1102 1103 void 1104 icmp6_mtudisc_update(ip6cp, validated) 1105 struct ip6ctlparam *ip6cp; 1106 int validated; 1107 { 1108 struct in6_addr *dst = ip6cp->ip6c_finaldst; 1109 struct icmp6_hdr *icmp6 = ip6cp->ip6c_icmp6; 1110 struct mbuf *m = ip6cp->ip6c_m; /* will be necessary for scope issue */ 1111 u_int mtu = ntohl(icmp6->icmp6_mtu); 1112 struct rtentry *rt = NULL; 1113 struct sockaddr_in6 sin6; 1114 1115 if (!validated) 1116 return; 1117 1118 bzero(&sin6, sizeof(sin6)); 1119 sin6.sin6_family = PF_INET6; 1120 sin6.sin6_len = sizeof(struct sockaddr_in6); 1121 sin6.sin6_addr = *dst; 1122 /* XXX normally, this won't happen */ 1123 if (IN6_IS_ADDR_LINKLOCAL(dst)) { 1124 sin6.sin6_addr.s6_addr16[1] = 1125 htons(m->m_pkthdr.rcvif->if_index); 1126 } 1127 /* sin6.sin6_scope_id = XXX: should be set if DST is a scoped addr */ 1128 rt = rtalloc1((struct sockaddr *)&sin6, 0, 1129 RTF_CLONING | RTF_PRCLONING); 1130 1131 if (rt && (rt->rt_flags & RTF_HOST) 1132 && !(rt->rt_rmx.rmx_locks & RTV_MTU)) { 1133 if (mtu < IPV6_MMTU) { 1134 /* xxx */ 1135 rt->rt_rmx.rmx_locks |= RTV_MTU; 1136 } else if (mtu < rt->rt_ifp->if_mtu && 1137 rt->rt_rmx.rmx_mtu > mtu) { 1138 icmp6stat.icp6s_pmtuchg++; 1139 rt->rt_rmx.rmx_mtu = mtu; 1140 } 1141 } 1142 if (rt) 1143 RTFREE(rt); 1144 } 1145 1146 /* 1147 * Process a Node Information Query packet, based on 1148 * draft-ietf-ipngwg-icmp-name-lookups-07. 1149 * 1150 * Spec incompatibilities: 1151 * - IPv6 Subject address handling 1152 * - IPv4 Subject address handling support missing 1153 * - Proxy reply (answer even if it's not for me) 1154 * - joins NI group address at in6_ifattach() time only, does not cope 1155 * with hostname changes by sethostname(3) 1156 */ 1157 #define hostnamelen strlen(hostname) 1158 static struct mbuf * 1159 ni6_input(m, off) 1160 struct mbuf *m; 1161 int off; 1162 { 1163 struct icmp6_nodeinfo *ni6, *nni6; 1164 struct mbuf *n = NULL; 1165 u_int16_t qtype; 1166 int subjlen; 1167 int replylen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo); 1168 struct ni_reply_fqdn *fqdn; 1169 int addrs; /* for NI_QTYPE_NODEADDR */ 1170 struct ifnet *ifp = NULL; /* for NI_QTYPE_NODEADDR */ 1171 struct sockaddr_in6 sin6; /* double meaning; ip6_dst and subjectaddr */ 1172 struct sockaddr_in6 sin6_d; /* XXX: we should retrieve this from m_aux */ 1173 struct ip6_hdr *ip6; 1174 int oldfqdn = 0; /* if 1, return pascal string (03 draft) */ 1175 char *subj = NULL; 1176 struct in6_ifaddr *ia6 = NULL; 1177 1178 ip6 = mtod(m, struct ip6_hdr *); 1179 #ifndef PULLDOWN_TEST 1180 ni6 = (struct icmp6_nodeinfo *)(mtod(m, caddr_t) + off); 1181 #else 1182 IP6_EXTHDR_GET(ni6, struct icmp6_nodeinfo *, m, off, sizeof(*ni6)); 1183 if (ni6 == NULL) { 1184 /* m is already reclaimed */ 1185 return NULL; 1186 } 1187 #endif 1188 1189 /* 1190 * Validate IPv6 destination address. 1191 * 1192 * The Responder must discard the Query without further processing 1193 * unless it is one of the Responder's unicast or anycast addresses, or 1194 * a link-local scope multicast address which the Responder has joined. 1195 * [icmp-name-lookups-07, Section 4.] 1196 */ 1197 bzero(&sin6, sizeof(sin6)); 1198 sin6.sin6_family = AF_INET6; 1199 sin6.sin6_len = sizeof(struct sockaddr_in6); 1200 bcopy(&ip6->ip6_dst, &sin6.sin6_addr, sizeof(sin6.sin6_addr)); 1201 /* XXX scopeid */ 1202 if ((ia6 = (struct in6_ifaddr *)ifa_ifwithaddr((struct sockaddr *)&sin6)) != NULL) { 1203 /* unicast/anycast, fine */ 1204 if ((ia6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 1205 (icmp6_nodeinfo & 4) == 0) { 1206 nd6log((LOG_DEBUG, "ni6_input: ignore node info to " 1207 "a temporary address in %s:%d", 1208 __FILE__, __LINE__)); 1209 goto bad; 1210 } 1211 } else if (IN6_IS_ADDR_MC_LINKLOCAL(&sin6.sin6_addr)) 1212 ; /* link-local multicast, fine */ 1213 else 1214 goto bad; 1215 1216 /* validate query Subject field. */ 1217 qtype = ntohs(ni6->ni_qtype); 1218 subjlen = m->m_pkthdr.len - off - sizeof(struct icmp6_nodeinfo); 1219 switch (qtype) { 1220 case NI_QTYPE_NOOP: 1221 case NI_QTYPE_SUPTYPES: 1222 /* 07 draft */ 1223 if (ni6->ni_code == ICMP6_NI_SUBJ_FQDN && subjlen == 0) 1224 break; 1225 /* FALLTHROUGH */ 1226 case NI_QTYPE_FQDN: 1227 case NI_QTYPE_NODEADDR: 1228 switch (ni6->ni_code) { 1229 case ICMP6_NI_SUBJ_IPV6: 1230 #if ICMP6_NI_SUBJ_IPV6 != 0 1231 case 0: 1232 #endif 1233 /* 1234 * backward compatibility - try to accept 03 draft 1235 * format, where no Subject is present. 1236 */ 1237 if (qtype == NI_QTYPE_FQDN && ni6->ni_code == 0 && 1238 subjlen == 0) { 1239 oldfqdn++; 1240 break; 1241 } 1242 #if ICMP6_NI_SUBJ_IPV6 != 0 1243 if (ni6->ni_code != ICMP6_NI_SUBJ_IPV6) 1244 goto bad; 1245 #endif 1246 1247 if (subjlen != sizeof(sin6.sin6_addr)) 1248 goto bad; 1249 1250 /* 1251 * Validate Subject address. 1252 * 1253 * Not sure what exactly "address belongs to the node" 1254 * means in the spec, is it just unicast, or what? 1255 * 1256 * At this moment we consider Subject address as 1257 * "belong to the node" if the Subject address equals 1258 * to the IPv6 destination address; validation for 1259 * IPv6 destination address should have done enough 1260 * check for us. 1261 * 1262 * We do not do proxy at this moment. 1263 */ 1264 /* m_pulldown instead of copy? */ 1265 m_copydata(m, off + sizeof(struct icmp6_nodeinfo), 1266 subjlen, (caddr_t)&sin6.sin6_addr); 1267 sin6.sin6_scope_id = in6_addr2scopeid(m->m_pkthdr.rcvif, 1268 &sin6.sin6_addr); 1269 #ifndef SCOPEDROUTING 1270 in6_embedscope(&sin6.sin6_addr, &sin6, NULL, NULL); 1271 #endif 1272 bzero(&sin6_d, sizeof(sin6_d)); 1273 sin6_d.sin6_family = AF_INET6; /* not used, actually */ 1274 sin6_d.sin6_len = sizeof(sin6_d); /* ditto */ 1275 sin6_d.sin6_addr = ip6->ip6_dst; 1276 sin6_d.sin6_scope_id = in6_addr2scopeid(m->m_pkthdr.rcvif, 1277 &ip6->ip6_dst); 1278 #ifndef SCOPEDROUTING 1279 in6_embedscope(&sin6_d.sin6_addr, &sin6_d, NULL, NULL); 1280 #endif 1281 subj = (char *)&sin6; 1282 if (SA6_ARE_ADDR_EQUAL(&sin6, &sin6_d)) 1283 break; 1284 1285 /* 1286 * XXX if we are to allow other cases, we should really 1287 * be careful about scope here. 1288 * basically, we should disallow queries toward IPv6 1289 * destination X with subject Y, if scope(X) > scope(Y). 1290 * if we allow scope(X) > scope(Y), it will result in 1291 * information leakage across scope boundary. 1292 */ 1293 goto bad; 1294 1295 case ICMP6_NI_SUBJ_FQDN: 1296 /* 1297 * Validate Subject name with gethostname(3). 1298 * 1299 * The behavior may need some debate, since: 1300 * - we are not sure if the node has FQDN as 1301 * hostname (returned by gethostname(3)). 1302 * - the code does wildcard match for truncated names. 1303 * however, we are not sure if we want to perform 1304 * wildcard match, if gethostname(3) side has 1305 * truncated hostname. 1306 */ 1307 n = ni6_nametodns(hostname, hostnamelen, 0); 1308 if (!n || n->m_next || n->m_len == 0) 1309 goto bad; 1310 IP6_EXTHDR_GET(subj, char *, m, 1311 off + sizeof(struct icmp6_nodeinfo), subjlen); 1312 if (subj == NULL) 1313 goto bad; 1314 if (!ni6_dnsmatch(subj, subjlen, mtod(n, const char *), 1315 n->m_len)) { 1316 goto bad; 1317 } 1318 m_freem(n); 1319 n = NULL; 1320 break; 1321 1322 case ICMP6_NI_SUBJ_IPV4: /* XXX: to be implemented? */ 1323 default: 1324 goto bad; 1325 } 1326 break; 1327 } 1328 1329 /* refuse based on configuration. XXX ICMP6_NI_REFUSED? */ 1330 switch (qtype) { 1331 case NI_QTYPE_FQDN: 1332 if ((icmp6_nodeinfo & 1) == 0) 1333 goto bad; 1334 break; 1335 case NI_QTYPE_NODEADDR: 1336 if ((icmp6_nodeinfo & 2) == 0) 1337 goto bad; 1338 break; 1339 } 1340 1341 /* guess reply length */ 1342 switch (qtype) { 1343 case NI_QTYPE_NOOP: 1344 break; /* no reply data */ 1345 case NI_QTYPE_SUPTYPES: 1346 replylen += sizeof(u_int32_t); 1347 break; 1348 case NI_QTYPE_FQDN: 1349 /* XXX will append an mbuf */ 1350 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1351 break; 1352 case NI_QTYPE_NODEADDR: 1353 addrs = ni6_addrs(ni6, m, &ifp, subj); 1354 if ((replylen += addrs * (sizeof(struct in6_addr) + 1355 sizeof(u_int32_t))) > MCLBYTES) 1356 replylen = MCLBYTES; /* XXX: will truncate pkt later */ 1357 break; 1358 default: 1359 /* 1360 * XXX: We must return a reply with the ICMP6 code 1361 * `unknown Qtype' in this case. However we regard the case 1362 * as an FQDN query for backward compatibility. 1363 * Older versions set a random value to this field, 1364 * so it rarely varies in the defined qtypes. 1365 * But the mechanism is not reliable... 1366 * maybe we should obsolete older versions. 1367 */ 1368 qtype = NI_QTYPE_FQDN; 1369 /* XXX will append an mbuf */ 1370 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1371 oldfqdn++; 1372 break; 1373 } 1374 1375 /* allocate an mbuf to reply. */ 1376 MGETHDR(n, M_DONTWAIT, m->m_type); 1377 if (n == NULL) { 1378 m_freem(m); 1379 return(NULL); 1380 } 1381 M_COPY_PKTHDR(n, m); /* just for recvif */ 1382 if (replylen > MHLEN) { 1383 if (replylen > MCLBYTES) { 1384 /* 1385 * XXX: should we try to allocate more? But MCLBYTES 1386 * is probably much larger than IPV6_MMTU... 1387 */ 1388 goto bad; 1389 } 1390 MCLGET(n, M_DONTWAIT); 1391 if ((n->m_flags & M_EXT) == 0) { 1392 goto bad; 1393 } 1394 } 1395 n->m_pkthdr.len = n->m_len = replylen; 1396 1397 /* copy mbuf header and IPv6 + Node Information base headers */ 1398 bcopy(mtod(m, caddr_t), mtod(n, caddr_t), sizeof(struct ip6_hdr)); 1399 nni6 = (struct icmp6_nodeinfo *)(mtod(n, struct ip6_hdr *) + 1); 1400 bcopy((caddr_t)ni6, (caddr_t)nni6, sizeof(struct icmp6_nodeinfo)); 1401 1402 /* qtype dependent procedure */ 1403 switch (qtype) { 1404 case NI_QTYPE_NOOP: 1405 nni6->ni_code = ICMP6_NI_SUCCESS; 1406 nni6->ni_flags = 0; 1407 break; 1408 case NI_QTYPE_SUPTYPES: 1409 { 1410 u_int32_t v; 1411 nni6->ni_code = ICMP6_NI_SUCCESS; 1412 nni6->ni_flags = htons(0x0000); /* raw bitmap */ 1413 /* supports NOOP, SUPTYPES, FQDN, and NODEADDR */ 1414 v = (u_int32_t)htonl(0x0000000f); 1415 bcopy(&v, nni6 + 1, sizeof(u_int32_t)); 1416 break; 1417 } 1418 case NI_QTYPE_FQDN: 1419 nni6->ni_code = ICMP6_NI_SUCCESS; 1420 fqdn = (struct ni_reply_fqdn *)(mtod(n, caddr_t) + 1421 sizeof(struct ip6_hdr) + 1422 sizeof(struct icmp6_nodeinfo)); 1423 nni6->ni_flags = 0; /* XXX: meaningless TTL */ 1424 fqdn->ni_fqdn_ttl = 0; /* ditto. */ 1425 /* 1426 * XXX do we really have FQDN in variable "hostname"? 1427 */ 1428 n->m_next = ni6_nametodns(hostname, hostnamelen, oldfqdn); 1429 if (n->m_next == NULL) 1430 goto bad; 1431 /* XXX we assume that n->m_next is not a chain */ 1432 if (n->m_next->m_next != NULL) 1433 goto bad; 1434 n->m_pkthdr.len += n->m_next->m_len; 1435 break; 1436 case NI_QTYPE_NODEADDR: 1437 { 1438 int lenlim, copied; 1439 1440 nni6->ni_code = ICMP6_NI_SUCCESS; 1441 n->m_pkthdr.len = n->m_len = 1442 sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo); 1443 lenlim = M_TRAILINGSPACE(n); 1444 copied = ni6_store_addrs(ni6, nni6, ifp, lenlim); 1445 /* XXX: reset mbuf length */ 1446 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) + 1447 sizeof(struct icmp6_nodeinfo) + copied; 1448 break; 1449 } 1450 default: 1451 break; /* XXX impossible! */ 1452 } 1453 1454 nni6->ni_type = ICMP6_NI_REPLY; 1455 m_freem(m); 1456 return(n); 1457 1458 bad: 1459 m_freem(m); 1460 if (n) 1461 m_freem(n); 1462 return(NULL); 1463 } 1464 #undef hostnamelen 1465 1466 /* 1467 * make a mbuf with DNS-encoded string. no compression support. 1468 * 1469 * XXX names with less than 2 dots (like "foo" or "foo.section") will be 1470 * treated as truncated name (two \0 at the end). this is a wild guess. 1471 */ 1472 static struct mbuf * 1473 ni6_nametodns(name, namelen, old) 1474 const char *name; 1475 int namelen; 1476 int old; /* return pascal string if non-zero */ 1477 { 1478 struct mbuf *m; 1479 char *cp, *ep; 1480 const char *p, *q; 1481 int i, len, nterm; 1482 1483 if (old) 1484 len = namelen + 1; 1485 else 1486 len = MCLBYTES; 1487 1488 /* because MAXHOSTNAMELEN is usually 256, we use cluster mbuf */ 1489 MGET(m, M_DONTWAIT, MT_DATA); 1490 if (m && len > MLEN) { 1491 MCLGET(m, M_DONTWAIT); 1492 if ((m->m_flags & M_EXT) == 0) 1493 goto fail; 1494 } 1495 if (!m) 1496 goto fail; 1497 m->m_next = NULL; 1498 1499 if (old) { 1500 m->m_len = len; 1501 *mtod(m, char *) = namelen; 1502 bcopy(name, mtod(m, char *) + 1, namelen); 1503 return m; 1504 } else { 1505 m->m_len = 0; 1506 cp = mtod(m, char *); 1507 ep = mtod(m, char *) + M_TRAILINGSPACE(m); 1508 1509 /* if not certain about my name, return empty buffer */ 1510 if (namelen == 0) 1511 return m; 1512 1513 /* 1514 * guess if it looks like shortened hostname, or FQDN. 1515 * shortened hostname needs two trailing "\0". 1516 */ 1517 i = 0; 1518 for (p = name; p < name + namelen; p++) { 1519 if (*p && *p == '.') 1520 i++; 1521 } 1522 if (i < 2) 1523 nterm = 2; 1524 else 1525 nterm = 1; 1526 1527 p = name; 1528 while (cp < ep && p < name + namelen) { 1529 i = 0; 1530 for (q = p; q < name + namelen && *q && *q != '.'; q++) 1531 i++; 1532 /* result does not fit into mbuf */ 1533 if (cp + i + 1 >= ep) 1534 goto fail; 1535 /* 1536 * DNS label length restriction, RFC1035 page 8. 1537 * "i == 0" case is included here to avoid returning 1538 * 0-length label on "foo..bar". 1539 */ 1540 if (i <= 0 || i >= 64) 1541 goto fail; 1542 *cp++ = i; 1543 bcopy(p, cp, i); 1544 cp += i; 1545 p = q; 1546 if (p < name + namelen && *p == '.') 1547 p++; 1548 } 1549 /* termination */ 1550 if (cp + nterm >= ep) 1551 goto fail; 1552 while (nterm-- > 0) 1553 *cp++ = '\0'; 1554 m->m_len = cp - mtod(m, char *); 1555 return m; 1556 } 1557 1558 panic("should not reach here"); 1559 /*NOTREACHED*/ 1560 1561 fail: 1562 if (m) 1563 m_freem(m); 1564 return NULL; 1565 } 1566 1567 /* 1568 * check if two DNS-encoded string matches. takes care of truncated 1569 * form (with \0\0 at the end). no compression support. 1570 * XXX upper/lowercase match (see RFC2065) 1571 */ 1572 static int 1573 ni6_dnsmatch(a, alen, b, blen) 1574 const char *a; 1575 int alen; 1576 const char *b; 1577 int blen; 1578 { 1579 const char *a0, *b0; 1580 int l; 1581 1582 /* simplest case - need validation? */ 1583 if (alen == blen && bcmp(a, b, alen) == 0) 1584 return 1; 1585 1586 a0 = a; 1587 b0 = b; 1588 1589 /* termination is mandatory */ 1590 if (alen < 2 || blen < 2) 1591 return 0; 1592 if (a0[alen - 1] != '\0' || b0[blen - 1] != '\0') 1593 return 0; 1594 alen--; 1595 blen--; 1596 1597 while (a - a0 < alen && b - b0 < blen) { 1598 if (a - a0 + 1 > alen || b - b0 + 1 > blen) 1599 return 0; 1600 1601 if ((signed char)a[0] < 0 || (signed char)b[0] < 0) 1602 return 0; 1603 /* we don't support compression yet */ 1604 if (a[0] >= 64 || b[0] >= 64) 1605 return 0; 1606 1607 /* truncated case */ 1608 if (a[0] == 0 && a - a0 == alen - 1) 1609 return 1; 1610 if (b[0] == 0 && b - b0 == blen - 1) 1611 return 1; 1612 if (a[0] == 0 || b[0] == 0) 1613 return 0; 1614 1615 if (a[0] != b[0]) 1616 return 0; 1617 l = a[0]; 1618 if (a - a0 + 1 + l > alen || b - b0 + 1 + l > blen) 1619 return 0; 1620 if (bcmp(a + 1, b + 1, l) != 0) 1621 return 0; 1622 1623 a += 1 + l; 1624 b += 1 + l; 1625 } 1626 1627 if (a - a0 == alen && b - b0 == blen) 1628 return 1; 1629 else 1630 return 0; 1631 } 1632 1633 /* 1634 * calculate the number of addresses to be returned in the node info reply. 1635 */ 1636 static int 1637 ni6_addrs(ni6, m, ifpp, subj) 1638 struct icmp6_nodeinfo *ni6; 1639 struct mbuf *m; 1640 struct ifnet **ifpp; 1641 char *subj; 1642 { 1643 struct ifnet *ifp; 1644 struct in6_ifaddr *ifa6; 1645 struct ifaddr *ifa; 1646 struct sockaddr_in6 *subj_ip6 = NULL; /* XXX pedant */ 1647 int addrs = 0, addrsofif, iffound = 0; 1648 int niflags = ni6->ni_flags; 1649 1650 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0) { 1651 switch (ni6->ni_code) { 1652 case ICMP6_NI_SUBJ_IPV6: 1653 if (subj == NULL) /* must be impossible... */ 1654 return(0); 1655 subj_ip6 = (struct sockaddr_in6 *)subj; 1656 break; 1657 default: 1658 /* 1659 * XXX: we only support IPv6 subject address for 1660 * this Qtype. 1661 */ 1662 return(0); 1663 } 1664 } 1665 1666 for (ifp = TAILQ_FIRST(&ifnet); ifp; ifp = TAILQ_NEXT(ifp, if_list)) 1667 { 1668 addrsofif = 0; 1669 TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list) 1670 { 1671 if (ifa->ifa_addr->sa_family != AF_INET6) 1672 continue; 1673 ifa6 = (struct in6_ifaddr *)ifa; 1674 1675 if ((niflags & NI_NODEADDR_FLAG_ALL) == 0 && 1676 IN6_ARE_ADDR_EQUAL(&subj_ip6->sin6_addr, 1677 &ifa6->ia_addr.sin6_addr)) 1678 iffound = 1; 1679 1680 /* 1681 * IPv4-mapped addresses can only be returned by a 1682 * Node Information proxy, since they represent 1683 * addresses of IPv4-only nodes, which perforce do 1684 * not implement this protocol. 1685 * [icmp-name-lookups-07, Section 5.4] 1686 * So we don't support NI_NODEADDR_FLAG_COMPAT in 1687 * this function at this moment. 1688 */ 1689 1690 /* What do we have to do about ::1? */ 1691 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1692 case IPV6_ADDR_SCOPE_LINKLOCAL: 1693 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0) 1694 continue; 1695 break; 1696 case IPV6_ADDR_SCOPE_SITELOCAL: 1697 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0) 1698 continue; 1699 break; 1700 case IPV6_ADDR_SCOPE_GLOBAL: 1701 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0) 1702 continue; 1703 break; 1704 default: 1705 continue; 1706 } 1707 1708 /* 1709 * check if anycast is okay. 1710 * XXX: just experimental. not in the spec. 1711 */ 1712 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 && 1713 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0) 1714 continue; /* we need only unicast addresses */ 1715 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 1716 (icmp6_nodeinfo & 4) == 0) { 1717 continue; 1718 } 1719 addrsofif++; /* count the address */ 1720 } 1721 if (iffound) { 1722 *ifpp = ifp; 1723 return(addrsofif); 1724 } 1725 1726 addrs += addrsofif; 1727 } 1728 1729 return(addrs); 1730 } 1731 1732 static int 1733 ni6_store_addrs(ni6, nni6, ifp0, resid) 1734 struct icmp6_nodeinfo *ni6, *nni6; 1735 struct ifnet *ifp0; 1736 int resid; 1737 { 1738 struct ifnet *ifp = ifp0 ? ifp0 : TAILQ_FIRST(&ifnet); 1739 struct in6_ifaddr *ifa6; 1740 struct ifaddr *ifa; 1741 struct ifnet *ifp_dep = NULL; 1742 int copied = 0, allow_deprecated = 0; 1743 u_char *cp = (u_char *)(nni6 + 1); 1744 int niflags = ni6->ni_flags; 1745 u_int32_t ltime; 1746 1747 if (ifp0 == NULL && !(niflags & NI_NODEADDR_FLAG_ALL)) 1748 return(0); /* needless to copy */ 1749 1750 again: 1751 1752 for (; ifp; ifp = TAILQ_NEXT(ifp, if_list)) 1753 { 1754 for (ifa = ifp->if_addrlist.tqh_first; ifa; 1755 ifa = ifa->ifa_list.tqe_next) 1756 { 1757 if (ifa->ifa_addr->sa_family != AF_INET6) 1758 continue; 1759 ifa6 = (struct in6_ifaddr *)ifa; 1760 1761 if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) != 0 && 1762 allow_deprecated == 0) { 1763 /* 1764 * prefererred address should be put before 1765 * deprecated addresses. 1766 */ 1767 1768 /* record the interface for later search */ 1769 if (ifp_dep == NULL) 1770 ifp_dep = ifp; 1771 1772 continue; 1773 } 1774 else if ((ifa6->ia6_flags & IN6_IFF_DEPRECATED) == 0 && 1775 allow_deprecated != 0) 1776 continue; /* we now collect deprecated addrs */ 1777 1778 /* What do we have to do about ::1? */ 1779 switch (in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1780 case IPV6_ADDR_SCOPE_LINKLOCAL: 1781 if ((niflags & NI_NODEADDR_FLAG_LINKLOCAL) == 0) 1782 continue; 1783 break; 1784 case IPV6_ADDR_SCOPE_SITELOCAL: 1785 if ((niflags & NI_NODEADDR_FLAG_SITELOCAL) == 0) 1786 continue; 1787 break; 1788 case IPV6_ADDR_SCOPE_GLOBAL: 1789 if ((niflags & NI_NODEADDR_FLAG_GLOBAL) == 0) 1790 continue; 1791 break; 1792 default: 1793 continue; 1794 } 1795 1796 /* 1797 * check if anycast is okay. 1798 * XXX: just experimental. not in the spec. 1799 */ 1800 if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0 && 1801 (niflags & NI_NODEADDR_FLAG_ANYCAST) == 0) 1802 continue; 1803 if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0 && 1804 (icmp6_nodeinfo & 4) == 0) { 1805 continue; 1806 } 1807 1808 /* now we can copy the address */ 1809 if (resid < sizeof(struct in6_addr) + 1810 sizeof(u_int32_t)) { 1811 /* 1812 * We give up much more copy. 1813 * Set the truncate flag and return. 1814 */ 1815 nni6->ni_flags |= 1816 NI_NODEADDR_FLAG_TRUNCATE; 1817 return(copied); 1818 } 1819 1820 /* 1821 * Set the TTL of the address. 1822 * The TTL value should be one of the following 1823 * according to the specification: 1824 * 1825 * 1. The remaining lifetime of a DHCP lease on the 1826 * address, or 1827 * 2. The remaining Valid Lifetime of a prefix from 1828 * which the address was derived through Stateless 1829 * Autoconfiguration. 1830 * 1831 * Note that we currently do not support stateful 1832 * address configuration by DHCPv6, so the former 1833 * case can't happen. 1834 */ 1835 if (ifa6->ia6_lifetime.ia6t_expire == 0) 1836 ltime = ND6_INFINITE_LIFETIME; 1837 else { 1838 if (ifa6->ia6_lifetime.ia6t_expire > 1839 time_second) 1840 ltime = htonl(ifa6->ia6_lifetime.ia6t_expire - time_second); 1841 else 1842 ltime = 0; 1843 } 1844 1845 bcopy(<ime, cp, sizeof(u_int32_t)); 1846 cp += sizeof(u_int32_t); 1847 1848 /* copy the address itself */ 1849 bcopy(&ifa6->ia_addr.sin6_addr, cp, 1850 sizeof(struct in6_addr)); 1851 /* XXX: KAME link-local hack; remove ifindex */ 1852 if (IN6_IS_ADDR_LINKLOCAL(&ifa6->ia_addr.sin6_addr)) 1853 ((struct in6_addr *)cp)->s6_addr16[1] = 0; 1854 cp += sizeof(struct in6_addr); 1855 1856 resid -= (sizeof(struct in6_addr) + sizeof(u_int32_t)); 1857 copied += (sizeof(struct in6_addr) + 1858 sizeof(u_int32_t)); 1859 } 1860 if (ifp0) /* we need search only on the specified IF */ 1861 break; 1862 } 1863 1864 if (allow_deprecated == 0 && ifp_dep != NULL) { 1865 ifp = ifp_dep; 1866 allow_deprecated = 1; 1867 1868 goto again; 1869 } 1870 1871 return(copied); 1872 } 1873 1874 /* 1875 * XXX almost dup'ed code with rip6_input. 1876 */ 1877 static int 1878 icmp6_rip6_input(mp, off) 1879 struct mbuf **mp; 1880 int off; 1881 { 1882 struct mbuf *m = *mp; 1883 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1884 struct in6pcb *in6p; 1885 struct in6pcb *last = NULL; 1886 struct sockaddr_in6 rip6src; 1887 struct icmp6_hdr *icmp6; 1888 struct mbuf *opts = NULL; 1889 1890 #ifndef PULLDOWN_TEST 1891 /* this is assumed to be safe. */ 1892 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off); 1893 #else 1894 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 1895 if (icmp6 == NULL) { 1896 /* m is already reclaimed */ 1897 return IPPROTO_DONE; 1898 } 1899 #endif 1900 1901 bzero(&rip6src, sizeof(rip6src)); 1902 rip6src.sin6_len = sizeof(struct sockaddr_in6); 1903 rip6src.sin6_family = AF_INET6; 1904 /* KAME hack: recover scopeid */ 1905 (void)in6_recoverscope(&rip6src, &ip6->ip6_src, m->m_pkthdr.rcvif); 1906 1907 LIST_FOREACH(in6p, &ripcb, inp_list) 1908 { 1909 if ((in6p->inp_vflag & INP_IPV6) == 0) 1910 continue; 1911 #ifdef HAVE_NRL_INPCB 1912 if (!(in6p->in6p_flags & INP_IPV6)) 1913 continue; 1914 #endif 1915 if (in6p->in6p_ip6_nxt != IPPROTO_ICMPV6) 1916 continue; 1917 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr) && 1918 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr, &ip6->ip6_dst)) 1919 continue; 1920 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr) && 1921 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr, &ip6->ip6_src)) 1922 continue; 1923 if (in6p->in6p_icmp6filt 1924 && ICMP6_FILTER_WILLBLOCK(icmp6->icmp6_type, 1925 in6p->in6p_icmp6filt)) 1926 continue; 1927 if (last) { 1928 struct mbuf *n; 1929 if ((n = m_copy(m, 0, (int)M_COPYALL)) != NULL) { 1930 if (last->in6p_flags & IN6P_CONTROLOPTS) 1931 ip6_savecontrol(last, &opts, ip6, n); 1932 /* strip intermediate headers */ 1933 m_adj(n, off); 1934 if (sbappendaddr(&last->in6p_socket->so_rcv, 1935 (struct sockaddr *)&rip6src, 1936 n, opts) == 0) { 1937 /* should notify about lost packet */ 1938 m_freem(n); 1939 if (opts) { 1940 m_freem(opts); 1941 } 1942 } else 1943 sorwakeup(last->in6p_socket); 1944 opts = NULL; 1945 } 1946 } 1947 last = in6p; 1948 } 1949 if (last) { 1950 if (last->in6p_flags & IN6P_CONTROLOPTS) 1951 ip6_savecontrol(last, &opts, ip6, m); 1952 /* strip intermediate headers */ 1953 m_adj(m, off); 1954 if (sbappendaddr(&last->in6p_socket->so_rcv, 1955 (struct sockaddr *)&rip6src, m, opts) == 0) { 1956 m_freem(m); 1957 if (opts) 1958 m_freem(opts); 1959 } else 1960 sorwakeup(last->in6p_socket); 1961 } else { 1962 m_freem(m); 1963 ip6stat.ip6s_delivered--; 1964 } 1965 return IPPROTO_DONE; 1966 } 1967 1968 /* 1969 * Reflect the ip6 packet back to the source. 1970 * OFF points to the icmp6 header, counted from the top of the mbuf. 1971 */ 1972 void 1973 icmp6_reflect(m, off) 1974 struct mbuf *m; 1975 size_t off; 1976 { 1977 struct ip6_hdr *ip6; 1978 struct icmp6_hdr *icmp6; 1979 struct in6_ifaddr *ia; 1980 struct in6_addr t, *src = 0; 1981 int plen; 1982 int type, code; 1983 struct ifnet *outif = NULL; 1984 struct sockaddr_in6 sa6_src, sa6_dst; 1985 #ifdef COMPAT_RFC1885 1986 int mtu = IPV6_MMTU; 1987 struct sockaddr_in6 *sin6 = &icmp6_reflect_rt.ro_dst; 1988 #endif 1989 1990 /* too short to reflect */ 1991 if (off < sizeof(struct ip6_hdr)) { 1992 nd6log((LOG_DEBUG, 1993 "sanity fail: off=%lx, sizeof(ip6)=%lx in %s:%d\n", 1994 (u_long)off, (u_long)sizeof(struct ip6_hdr), 1995 __FILE__, __LINE__)); 1996 goto bad; 1997 } 1998 1999 /* 2000 * If there are extra headers between IPv6 and ICMPv6, strip 2001 * off that header first. 2002 */ 2003 #ifdef DIAGNOSTIC 2004 if (sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) > MHLEN) 2005 panic("assumption failed in icmp6_reflect"); 2006 #endif 2007 if (off > sizeof(struct ip6_hdr)) { 2008 size_t l; 2009 struct ip6_hdr nip6; 2010 2011 l = off - sizeof(struct ip6_hdr); 2012 m_copydata(m, 0, sizeof(nip6), (caddr_t)&nip6); 2013 m_adj(m, l); 2014 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 2015 if (m->m_len < l) { 2016 if ((m = m_pullup(m, l)) == NULL) 2017 return; 2018 } 2019 bcopy((caddr_t)&nip6, mtod(m, caddr_t), sizeof(nip6)); 2020 } else /* off == sizeof(struct ip6_hdr) */ { 2021 size_t l; 2022 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 2023 if (m->m_len < l) { 2024 if ((m = m_pullup(m, l)) == NULL) 2025 return; 2026 } 2027 } 2028 plen = m->m_pkthdr.len - sizeof(struct ip6_hdr); 2029 ip6 = mtod(m, struct ip6_hdr *); 2030 ip6->ip6_nxt = IPPROTO_ICMPV6; 2031 icmp6 = (struct icmp6_hdr *)(ip6 + 1); 2032 type = icmp6->icmp6_type; /* keep type for statistics */ 2033 code = icmp6->icmp6_code; /* ditto. */ 2034 2035 t = ip6->ip6_dst; 2036 /* 2037 * ip6_input() drops a packet if its src is multicast. 2038 * So, the src is never multicast. 2039 */ 2040 ip6->ip6_dst = ip6->ip6_src; 2041 2042 /* 2043 * XXX: make sure to embed scope zone information, using 2044 * already embedded IDs or the received interface (if any). 2045 * Note that rcvif may be NULL. 2046 * TODO: scoped routing case (XXX). 2047 */ 2048 bzero(&sa6_src, sizeof(sa6_src)); 2049 sa6_src.sin6_family = AF_INET6; 2050 sa6_src.sin6_len = sizeof(sa6_src); 2051 sa6_src.sin6_addr = ip6->ip6_dst; 2052 in6_recoverscope(&sa6_src, &ip6->ip6_dst, m->m_pkthdr.rcvif); 2053 in6_embedscope(&ip6->ip6_dst, &sa6_src, NULL, NULL); 2054 bzero(&sa6_dst, sizeof(sa6_dst)); 2055 sa6_dst.sin6_family = AF_INET6; 2056 sa6_dst.sin6_len = sizeof(sa6_dst); 2057 sa6_dst.sin6_addr = t; 2058 in6_recoverscope(&sa6_dst, &t, m->m_pkthdr.rcvif); 2059 in6_embedscope(&t, &sa6_dst, NULL, NULL); 2060 2061 #ifdef COMPAT_RFC1885 2062 /* 2063 * xxx guess MTU 2064 * RFC 1885 requires that echo reply should be truncated if it 2065 * does not fit in with (return) path MTU, but the description was 2066 * removed in the new spec. 2067 */ 2068 if (icmp6_reflect_rt.ro_rt == 0 || 2069 ! (IN6_ARE_ADDR_EQUAL(&sin6->sin6_addr, &ip6->ip6_dst))) { 2070 if (icmp6_reflect_rt.ro_rt) { 2071 RTFREE(icmp6_reflect_rt.ro_rt); 2072 icmp6_reflect_rt.ro_rt = 0; 2073 } 2074 bzero(sin6, sizeof(*sin6)); 2075 sin6->sin6_family = PF_INET6; 2076 sin6->sin6_len = sizeof(struct sockaddr_in6); 2077 sin6->sin6_addr = ip6->ip6_dst; 2078 2079 rtalloc_ign((struct route *)&icmp6_reflect_rt.ro_rt, 2080 RTF_PRCLONING); 2081 } 2082 2083 if (icmp6_reflect_rt.ro_rt == 0) 2084 goto bad; 2085 2086 if ((icmp6_reflect_rt.ro_rt->rt_flags & RTF_HOST) 2087 && mtu < icmp6_reflect_rt.ro_rt->rt_ifp->if_mtu) 2088 mtu = icmp6_reflect_rt.ro_rt->rt_rmx.rmx_mtu; 2089 2090 if (mtu < m->m_pkthdr.len) { 2091 plen -= (m->m_pkthdr.len - mtu); 2092 m_adj(m, mtu - m->m_pkthdr.len); 2093 } 2094 #endif 2095 /* 2096 * If the incoming packet was addressed directly to us(i.e. unicast), 2097 * use dst as the src for the reply. 2098 * The IN6_IFF_NOTREADY case would be VERY rare, but is possible 2099 * (for example) when we encounter an error while forwarding procedure 2100 * destined to a duplicated address of ours. 2101 */ 2102 for (ia = in6_ifaddr; ia; ia = ia->ia_next) 2103 if (IN6_ARE_ADDR_EQUAL(&t, &ia->ia_addr.sin6_addr) && 2104 (ia->ia6_flags & (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY)) == 0) { 2105 src = &t; 2106 break; 2107 } 2108 if (ia == NULL && IN6_IS_ADDR_LINKLOCAL(&t) && (m->m_flags & M_LOOP)) { 2109 /* 2110 * This is the case if the dst is our link-local address 2111 * and the sender is also ourseleves. 2112 */ 2113 src = &t; 2114 } 2115 2116 if (src == 0) { 2117 int e; 2118 struct route_in6 ro; 2119 2120 /* 2121 * This case matches to multicasts, our anycast, or unicasts 2122 * that we do not own. Select a source address based on the 2123 * source address of the erroneous packet. 2124 */ 2125 bzero(&ro, sizeof(ro)); 2126 src = in6_selectsrc(&sa6_src, NULL, NULL, &ro, NULL, &e); 2127 if (ro.ro_rt) 2128 RTFREE(ro.ro_rt); /* XXX: we could use this */ 2129 if (src == NULL) { 2130 nd6log((LOG_DEBUG, 2131 "icmp6_reflect: source can't be determined: " 2132 "dst=%s, error=%d\n", 2133 ip6_sprintf(&sa6_src.sin6_addr), e)); 2134 goto bad; 2135 } 2136 } 2137 2138 ip6->ip6_src = *src; 2139 2140 ip6->ip6_flow = 0; 2141 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2142 ip6->ip6_vfc |= IPV6_VERSION; 2143 ip6->ip6_nxt = IPPROTO_ICMPV6; 2144 if (m->m_pkthdr.rcvif) { 2145 /* XXX: This may not be the outgoing interface */ 2146 ip6->ip6_hlim = nd_ifinfo[m->m_pkthdr.rcvif->if_index].chlim; 2147 } else 2148 ip6->ip6_hlim = ip6_defhlim; 2149 2150 icmp6->icmp6_cksum = 0; 2151 icmp6->icmp6_cksum = in6_cksum(m, IPPROTO_ICMPV6, 2152 sizeof(struct ip6_hdr), plen); 2153 2154 /* 2155 * XXX option handling 2156 */ 2157 2158 m->m_flags &= ~(M_BCAST|M_MCAST); 2159 #ifdef IPSEC 2160 /* Don't lookup socket */ 2161 (void)ipsec_setsocket(m, NULL); 2162 #endif /*IPSEC*/ 2163 2164 #ifdef COMPAT_RFC1885 2165 ip6_output(m, NULL, &icmp6_reflect_rt, 0, NULL, &outif); 2166 #else 2167 ip6_output(m, NULL, NULL, 0, NULL, &outif); 2168 #endif 2169 if (outif) 2170 icmp6_ifoutstat_inc(outif, type, code); 2171 2172 return; 2173 2174 bad: 2175 m_freem(m); 2176 return; 2177 } 2178 2179 void 2180 icmp6_fasttimo() 2181 { 2182 2183 mld6_fasttimeo(); 2184 } 2185 2186 static const char * 2187 icmp6_redirect_diag(src6, dst6, tgt6) 2188 struct in6_addr *src6; 2189 struct in6_addr *dst6; 2190 struct in6_addr *tgt6; 2191 { 2192 static char buf[1024]; 2193 snprintf(buf, sizeof(buf), "(src=%s dst=%s tgt=%s)", 2194 ip6_sprintf(src6), ip6_sprintf(dst6), ip6_sprintf(tgt6)); 2195 return buf; 2196 } 2197 2198 void 2199 icmp6_redirect_input(m, off) 2200 struct mbuf *m; 2201 int off; 2202 { 2203 struct ifnet *ifp = m->m_pkthdr.rcvif; 2204 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 2205 struct nd_redirect *nd_rd; 2206 int icmp6len = ntohs(ip6->ip6_plen); 2207 char *lladdr = NULL; 2208 int lladdrlen = 0; 2209 u_char *redirhdr = NULL; 2210 int redirhdrlen = 0; 2211 struct rtentry *rt = NULL; 2212 int is_router; 2213 int is_onlink; 2214 struct in6_addr src6 = ip6->ip6_src; 2215 struct in6_addr redtgt6; 2216 struct in6_addr reddst6; 2217 union nd_opts ndopts; 2218 2219 if (!m || !ifp) 2220 return; 2221 2222 /* XXX if we are router, we don't update route by icmp6 redirect */ 2223 if (ip6_forwarding) 2224 goto freeit; 2225 if (!icmp6_rediraccept) 2226 goto freeit; 2227 2228 #ifndef PULLDOWN_TEST 2229 IP6_EXTHDR_CHECK(m, off, icmp6len,); 2230 nd_rd = (struct nd_redirect *)((caddr_t)ip6 + off); 2231 #else 2232 IP6_EXTHDR_GET(nd_rd, struct nd_redirect *, m, off, icmp6len); 2233 if (nd_rd == NULL) { 2234 icmp6stat.icp6s_tooshort++; 2235 return; 2236 } 2237 #endif 2238 redtgt6 = nd_rd->nd_rd_target; 2239 reddst6 = nd_rd->nd_rd_dst; 2240 2241 if (IN6_IS_ADDR_LINKLOCAL(&redtgt6)) 2242 redtgt6.s6_addr16[1] = htons(ifp->if_index); 2243 if (IN6_IS_ADDR_LINKLOCAL(&reddst6)) 2244 reddst6.s6_addr16[1] = htons(ifp->if_index); 2245 2246 /* validation */ 2247 if (!IN6_IS_ADDR_LINKLOCAL(&src6)) { 2248 nd6log((LOG_ERR, 2249 "ICMP6 redirect sent from %s rejected; " 2250 "must be from linklocal\n", ip6_sprintf(&src6))); 2251 goto bad; 2252 } 2253 if (ip6->ip6_hlim != 255) { 2254 nd6log((LOG_ERR, 2255 "ICMP6 redirect sent from %s rejected; " 2256 "hlim=%d (must be 255)\n", 2257 ip6_sprintf(&src6), ip6->ip6_hlim)); 2258 goto bad; 2259 } 2260 { 2261 /* ip6->ip6_src must be equal to gw for icmp6->icmp6_reddst */ 2262 struct sockaddr_in6 sin6; 2263 struct in6_addr *gw6; 2264 2265 bzero(&sin6, sizeof(sin6)); 2266 sin6.sin6_family = AF_INET6; 2267 sin6.sin6_len = sizeof(struct sockaddr_in6); 2268 bcopy(&reddst6, &sin6.sin6_addr, sizeof(reddst6)); 2269 rt = rtalloc1((struct sockaddr *)&sin6, 0, 0UL); 2270 if (rt) { 2271 if (rt->rt_gateway == NULL || 2272 rt->rt_gateway->sa_family != AF_INET6) { 2273 nd6log((LOG_ERR, 2274 "ICMP6 redirect rejected; no route " 2275 "with inet6 gateway found for redirect dst: %s\n", 2276 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2277 RTFREE(rt); 2278 goto bad; 2279 } 2280 2281 gw6 = &(((struct sockaddr_in6 *)rt->rt_gateway)->sin6_addr); 2282 if (bcmp(&src6, gw6, sizeof(struct in6_addr)) != 0) { 2283 nd6log((LOG_ERR, 2284 "ICMP6 redirect rejected; " 2285 "not equal to gw-for-src=%s (must be same): " 2286 "%s\n", 2287 ip6_sprintf(gw6), 2288 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2289 RTFREE(rt); 2290 goto bad; 2291 } 2292 } else { 2293 nd6log((LOG_ERR, 2294 "ICMP6 redirect rejected; " 2295 "no route found for redirect dst: %s\n", 2296 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2297 goto bad; 2298 } 2299 RTFREE(rt); 2300 rt = NULL; 2301 } 2302 if (IN6_IS_ADDR_MULTICAST(&reddst6)) { 2303 nd6log((LOG_ERR, 2304 "ICMP6 redirect rejected; " 2305 "redirect dst must be unicast: %s\n", 2306 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2307 goto bad; 2308 } 2309 2310 is_router = is_onlink = 0; 2311 if (IN6_IS_ADDR_LINKLOCAL(&redtgt6)) 2312 is_router = 1; /* router case */ 2313 if (bcmp(&redtgt6, &reddst6, sizeof(redtgt6)) == 0) 2314 is_onlink = 1; /* on-link destination case */ 2315 if (!is_router && !is_onlink) { 2316 nd6log((LOG_ERR, 2317 "ICMP6 redirect rejected; " 2318 "neither router case nor onlink case: %s\n", 2319 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2320 goto bad; 2321 } 2322 /* validation passed */ 2323 2324 icmp6len -= sizeof(*nd_rd); 2325 nd6_option_init(nd_rd + 1, icmp6len, &ndopts); 2326 if (nd6_options(&ndopts) < 0) { 2327 nd6log((LOG_INFO, "icmp6_redirect_input: " 2328 "invalid ND option, rejected: %s\n", 2329 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2330 /* nd6_options have incremented stats */ 2331 goto freeit; 2332 } 2333 2334 if (ndopts.nd_opts_tgt_lladdr) { 2335 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 2336 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 2337 } 2338 2339 if (ndopts.nd_opts_rh) { 2340 redirhdrlen = ndopts.nd_opts_rh->nd_opt_rh_len; 2341 redirhdr = (u_char *)(ndopts.nd_opts_rh + 1); /* xxx */ 2342 } 2343 2344 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 2345 nd6log((LOG_INFO, 2346 "icmp6_redirect_input: lladdrlen mismatch for %s " 2347 "(if %d, icmp6 packet %d): %s\n", 2348 ip6_sprintf(&redtgt6), ifp->if_addrlen, lladdrlen - 2, 2349 icmp6_redirect_diag(&src6, &reddst6, &redtgt6))); 2350 goto bad; 2351 } 2352 2353 /* RFC 2461 8.3 */ 2354 nd6_cache_lladdr(ifp, &redtgt6, lladdr, lladdrlen, ND_REDIRECT, 2355 is_onlink ? ND_REDIRECT_ONLINK : ND_REDIRECT_ROUTER); 2356 2357 if (!is_onlink) { /* better router case. perform rtredirect. */ 2358 /* perform rtredirect */ 2359 struct sockaddr_in6 sdst; 2360 struct sockaddr_in6 sgw; 2361 struct sockaddr_in6 ssrc; 2362 2363 bzero(&sdst, sizeof(sdst)); 2364 bzero(&sgw, sizeof(sgw)); 2365 bzero(&ssrc, sizeof(ssrc)); 2366 sdst.sin6_family = sgw.sin6_family = ssrc.sin6_family = AF_INET6; 2367 sdst.sin6_len = sgw.sin6_len = ssrc.sin6_len = 2368 sizeof(struct sockaddr_in6); 2369 bcopy(&redtgt6, &sgw.sin6_addr, sizeof(struct in6_addr)); 2370 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2371 bcopy(&src6, &ssrc.sin6_addr, sizeof(struct in6_addr)); 2372 rtredirect((struct sockaddr *)&sdst, (struct sockaddr *)&sgw, 2373 (struct sockaddr *)NULL, RTF_GATEWAY | RTF_HOST, 2374 (struct sockaddr *)&ssrc, 2375 (struct rtentry **)NULL); 2376 } 2377 /* finally update cached route in each socket via pfctlinput */ 2378 { 2379 struct sockaddr_in6 sdst; 2380 2381 bzero(&sdst, sizeof(sdst)); 2382 sdst.sin6_family = AF_INET6; 2383 sdst.sin6_len = sizeof(struct sockaddr_in6); 2384 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2385 pfctlinput(PRC_REDIRECT_HOST, (struct sockaddr *)&sdst); 2386 #ifdef IPSEC 2387 key_sa_routechange((struct sockaddr *)&sdst); 2388 #endif 2389 } 2390 2391 freeit: 2392 m_freem(m); 2393 return; 2394 2395 bad: 2396 icmp6stat.icp6s_badredirect++; 2397 m_freem(m); 2398 } 2399 2400 void 2401 icmp6_redirect_output(m0, rt) 2402 struct mbuf *m0; 2403 struct rtentry *rt; 2404 { 2405 struct ifnet *ifp; /* my outgoing interface */ 2406 struct in6_addr *ifp_ll6; 2407 struct in6_addr *router_ll6; 2408 struct ip6_hdr *sip6; /* m0 as struct ip6_hdr */ 2409 struct mbuf *m = NULL; /* newly allocated one */ 2410 struct ip6_hdr *ip6; /* m as struct ip6_hdr */ 2411 struct nd_redirect *nd_rd; 2412 size_t maxlen; 2413 u_char *p; 2414 struct ifnet *outif = NULL; 2415 struct sockaddr_in6 src_sa; 2416 2417 icmp6_errcount(&icmp6stat.icp6s_outerrhist, ND_REDIRECT, 0); 2418 2419 /* if we are not router, we don't send icmp6 redirect */ 2420 if (!ip6_forwarding || ip6_accept_rtadv) 2421 goto fail; 2422 2423 /* sanity check */ 2424 if (!m0 || !rt || !(rt->rt_flags & RTF_UP) || !(ifp = rt->rt_ifp)) 2425 goto fail; 2426 2427 /* 2428 * Address check: 2429 * the source address must identify a neighbor, and 2430 * the destination address must not be a multicast address 2431 * [RFC 2461, sec 8.2] 2432 */ 2433 sip6 = mtod(m0, struct ip6_hdr *); 2434 bzero(&src_sa, sizeof(src_sa)); 2435 src_sa.sin6_family = AF_INET6; 2436 src_sa.sin6_len = sizeof(src_sa); 2437 src_sa.sin6_addr = sip6->ip6_src; 2438 /* we don't currently use sin6_scope_id, but eventually use it */ 2439 src_sa.sin6_scope_id = in6_addr2scopeid(ifp, &sip6->ip6_src); 2440 if (nd6_is_addr_neighbor(&src_sa, ifp) == 0) 2441 goto fail; 2442 if (IN6_IS_ADDR_MULTICAST(&sip6->ip6_dst)) 2443 goto fail; /* what should we do here? */ 2444 2445 /* rate limit */ 2446 if (icmp6_ratelimit(&sip6->ip6_src, ND_REDIRECT, 0)) 2447 goto fail; 2448 2449 /* 2450 * Since we are going to append up to 1280 bytes (= IPV6_MMTU), 2451 * we almost always ask for an mbuf cluster for simplicity. 2452 * (MHLEN < IPV6_MMTU is almost always true) 2453 */ 2454 #if IPV6_MMTU >= MCLBYTES 2455 # error assumption failed about IPV6_MMTU and MCLBYTES 2456 #endif 2457 MGETHDR(m, M_DONTWAIT, MT_HEADER); 2458 if (m && IPV6_MMTU >= MHLEN) 2459 MCLGET(m, M_DONTWAIT); 2460 if (!m) 2461 goto fail; 2462 m->m_pkthdr.rcvif = NULL; 2463 m->m_len = 0; 2464 maxlen = M_TRAILINGSPACE(m); 2465 maxlen = min(IPV6_MMTU, maxlen); 2466 /* just for safety */ 2467 if (maxlen < sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) + 2468 ((sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7)) { 2469 goto fail; 2470 } 2471 2472 { 2473 /* get ip6 linklocal address for ifp(my outgoing interface). */ 2474 struct in6_ifaddr *ia; 2475 if ((ia = in6ifa_ifpforlinklocal(ifp, 2476 IN6_IFF_NOTREADY| 2477 IN6_IFF_ANYCAST)) == NULL) 2478 goto fail; 2479 ifp_ll6 = &ia->ia_addr.sin6_addr; 2480 } 2481 2482 /* get ip6 linklocal address for the router. */ 2483 if (rt->rt_gateway && (rt->rt_flags & RTF_GATEWAY)) { 2484 struct sockaddr_in6 *sin6; 2485 sin6 = (struct sockaddr_in6 *)rt->rt_gateway; 2486 router_ll6 = &sin6->sin6_addr; 2487 if (!IN6_IS_ADDR_LINKLOCAL(router_ll6)) 2488 router_ll6 = (struct in6_addr *)NULL; 2489 } else 2490 router_ll6 = (struct in6_addr *)NULL; 2491 2492 /* ip6 */ 2493 ip6 = mtod(m, struct ip6_hdr *); 2494 ip6->ip6_flow = 0; 2495 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2496 ip6->ip6_vfc |= IPV6_VERSION; 2497 /* ip6->ip6_plen will be set later */ 2498 ip6->ip6_nxt = IPPROTO_ICMPV6; 2499 ip6->ip6_hlim = 255; 2500 /* ip6->ip6_src must be linklocal addr for my outgoing if. */ 2501 bcopy(ifp_ll6, &ip6->ip6_src, sizeof(struct in6_addr)); 2502 bcopy(&sip6->ip6_src, &ip6->ip6_dst, sizeof(struct in6_addr)); 2503 2504 /* ND Redirect */ 2505 nd_rd = (struct nd_redirect *)(ip6 + 1); 2506 nd_rd->nd_rd_type = ND_REDIRECT; 2507 nd_rd->nd_rd_code = 0; 2508 nd_rd->nd_rd_reserved = 0; 2509 if (rt->rt_flags & RTF_GATEWAY) { 2510 /* 2511 * nd_rd->nd_rd_target must be a link-local address in 2512 * better router cases. 2513 */ 2514 if (!router_ll6) 2515 goto fail; 2516 bcopy(router_ll6, &nd_rd->nd_rd_target, 2517 sizeof(nd_rd->nd_rd_target)); 2518 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2519 sizeof(nd_rd->nd_rd_dst)); 2520 } else { 2521 /* make sure redtgt == reddst */ 2522 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_target, 2523 sizeof(nd_rd->nd_rd_target)); 2524 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2525 sizeof(nd_rd->nd_rd_dst)); 2526 } 2527 2528 p = (u_char *)(nd_rd + 1); 2529 2530 if (!router_ll6) 2531 goto nolladdropt; 2532 2533 { 2534 /* target lladdr option */ 2535 struct rtentry *rt_router = NULL; 2536 int len; 2537 struct sockaddr_dl *sdl; 2538 struct nd_opt_hdr *nd_opt; 2539 char *lladdr; 2540 2541 rt_router = nd6_lookup(router_ll6, 0, ifp); 2542 if (!rt_router) 2543 goto nolladdropt; 2544 len = sizeof(*nd_opt) + ifp->if_addrlen; 2545 len = (len + 7) & ~7; /*round by 8*/ 2546 /* safety check */ 2547 if (len + (p - (u_char *)ip6) > maxlen) 2548 goto nolladdropt; 2549 if (!(rt_router->rt_flags & RTF_GATEWAY) && 2550 (rt_router->rt_flags & RTF_LLINFO) && 2551 (rt_router->rt_gateway->sa_family == AF_LINK) && 2552 (sdl = (struct sockaddr_dl *)rt_router->rt_gateway) && 2553 sdl->sdl_alen) { 2554 nd_opt = (struct nd_opt_hdr *)p; 2555 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 2556 nd_opt->nd_opt_len = len >> 3; 2557 lladdr = (char *)(nd_opt + 1); 2558 bcopy(LLADDR(sdl), lladdr, ifp->if_addrlen); 2559 p += len; 2560 } 2561 } 2562 nolladdropt:; 2563 2564 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2565 2566 /* just to be safe */ 2567 #ifdef M_DECRYPTED /*not openbsd*/ 2568 if (m0->m_flags & M_DECRYPTED) 2569 goto noredhdropt; 2570 #endif 2571 if (p - (u_char *)ip6 > maxlen) 2572 goto noredhdropt; 2573 2574 { 2575 /* redirected header option */ 2576 int len; 2577 struct nd_opt_rd_hdr *nd_opt_rh; 2578 2579 /* 2580 * compute the maximum size for icmp6 redirect header option. 2581 * XXX room for auth header? 2582 */ 2583 len = maxlen - (p - (u_char *)ip6); 2584 len &= ~7; 2585 2586 /* This is just for simplicity. */ 2587 if (m0->m_pkthdr.len != m0->m_len) { 2588 if (m0->m_next) { 2589 m_freem(m0->m_next); 2590 m0->m_next = NULL; 2591 } 2592 m0->m_pkthdr.len = m0->m_len; 2593 } 2594 2595 /* 2596 * Redirected header option spec (RFC2461 4.6.3) talks nothing 2597 * about padding/truncate rule for the original IP packet. 2598 * From the discussion on IPv6imp in Feb 1999, the consensus was: 2599 * - "attach as much as possible" is the goal 2600 * - pad if not aligned (original size can be guessed by original 2601 * ip6 header) 2602 * Following code adds the padding if it is simple enough, 2603 * and truncates if not. 2604 */ 2605 if (m0->m_next || m0->m_pkthdr.len != m0->m_len) 2606 panic("assumption failed in %s:%d\n", __FILE__, __LINE__); 2607 2608 if (len - sizeof(*nd_opt_rh) < m0->m_pkthdr.len) { 2609 /* not enough room, truncate */ 2610 m0->m_pkthdr.len = m0->m_len = len - sizeof(*nd_opt_rh); 2611 } else { 2612 /* enough room, pad or truncate */ 2613 size_t extra; 2614 2615 extra = m0->m_pkthdr.len % 8; 2616 if (extra) { 2617 /* pad if easy enough, truncate if not */ 2618 if (8 - extra <= M_TRAILINGSPACE(m0)) { 2619 /* pad */ 2620 m0->m_len += (8 - extra); 2621 m0->m_pkthdr.len += (8 - extra); 2622 } else { 2623 /* truncate */ 2624 m0->m_pkthdr.len -= extra; 2625 m0->m_len -= extra; 2626 } 2627 } 2628 len = m0->m_pkthdr.len + sizeof(*nd_opt_rh); 2629 m0->m_pkthdr.len = m0->m_len = len - sizeof(*nd_opt_rh); 2630 } 2631 2632 nd_opt_rh = (struct nd_opt_rd_hdr *)p; 2633 bzero(nd_opt_rh, sizeof(*nd_opt_rh)); 2634 nd_opt_rh->nd_opt_rh_type = ND_OPT_REDIRECTED_HEADER; 2635 nd_opt_rh->nd_opt_rh_len = len >> 3; 2636 p += sizeof(*nd_opt_rh); 2637 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2638 2639 /* connect m0 to m */ 2640 m->m_next = m0; 2641 m->m_pkthdr.len = m->m_len + m0->m_len; 2642 } 2643 noredhdropt:; 2644 2645 if (IN6_IS_ADDR_LINKLOCAL(&sip6->ip6_src)) 2646 sip6->ip6_src.s6_addr16[1] = 0; 2647 if (IN6_IS_ADDR_LINKLOCAL(&sip6->ip6_dst)) 2648 sip6->ip6_dst.s6_addr16[1] = 0; 2649 #if 0 2650 if (IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_src)) 2651 ip6->ip6_src.s6_addr16[1] = 0; 2652 if (IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_dst)) 2653 ip6->ip6_dst.s6_addr16[1] = 0; 2654 #endif 2655 if (IN6_IS_ADDR_LINKLOCAL(&nd_rd->nd_rd_target)) 2656 nd_rd->nd_rd_target.s6_addr16[1] = 0; 2657 if (IN6_IS_ADDR_LINKLOCAL(&nd_rd->nd_rd_dst)) 2658 nd_rd->nd_rd_dst.s6_addr16[1] = 0; 2659 2660 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr)); 2661 2662 nd_rd->nd_rd_cksum = 0; 2663 nd_rd->nd_rd_cksum 2664 = in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), ntohs(ip6->ip6_plen)); 2665 2666 /* send the packet to outside... */ 2667 #ifdef IPSEC 2668 /* Don't lookup socket */ 2669 (void)ipsec_setsocket(m, NULL); 2670 #endif /*IPSEC*/ 2671 ip6_output(m, NULL, NULL, 0, NULL, &outif); 2672 if (outif) { 2673 icmp6_ifstat_inc(outif, ifs6_out_msg); 2674 icmp6_ifstat_inc(outif, ifs6_out_redirect); 2675 } 2676 icmp6stat.icp6s_outhist[ND_REDIRECT]++; 2677 2678 return; 2679 2680 fail: 2681 if (m) 2682 m_freem(m); 2683 if (m0) 2684 m_freem(m0); 2685 } 2686 2687 #ifdef HAVE_NRL_INPCB 2688 #define sotoin6pcb sotoinpcb 2689 #define in6pcb inpcb 2690 #define in6p_icmp6filt inp_icmp6filt 2691 #endif 2692 /* 2693 * ICMPv6 socket option processing. 2694 */ 2695 int 2696 icmp6_ctloutput(so, sopt) 2697 struct socket *so; 2698 struct sockopt *sopt; 2699 { 2700 int error = 0; 2701 int optlen; 2702 struct inpcb *inp = sotoinpcb(so); 2703 int level, op, optname; 2704 2705 if (sopt) { 2706 level = sopt->sopt_level; 2707 op = sopt->sopt_dir; 2708 optname = sopt->sopt_name; 2709 optlen = sopt->sopt_valsize; 2710 } else 2711 level = op = optname = optlen = 0; 2712 2713 if (level != IPPROTO_ICMPV6) { 2714 return EINVAL; 2715 } 2716 2717 switch (op) { 2718 case PRCO_SETOPT: 2719 switch (optname) { 2720 case ICMP6_FILTER: 2721 { 2722 struct icmp6_filter *p; 2723 2724 if (optlen != sizeof(*p)) { 2725 error = EMSGSIZE; 2726 break; 2727 } 2728 if (inp->in6p_icmp6filt == NULL) { 2729 error = EINVAL; 2730 break; 2731 } 2732 error = sooptcopyin(sopt, inp->in6p_icmp6filt, optlen, 2733 optlen); 2734 break; 2735 } 2736 2737 default: 2738 error = ENOPROTOOPT; 2739 break; 2740 } 2741 break; 2742 2743 case PRCO_GETOPT: 2744 switch (optname) { 2745 case ICMP6_FILTER: 2746 { 2747 if (inp->in6p_icmp6filt == NULL) { 2748 error = EINVAL; 2749 break; 2750 } 2751 error = sooptcopyout(sopt, inp->in6p_icmp6filt, 2752 sizeof(struct icmp6_filter)); 2753 break; 2754 } 2755 2756 default: 2757 error = ENOPROTOOPT; 2758 break; 2759 } 2760 break; 2761 } 2762 2763 return(error); 2764 } 2765 #ifdef HAVE_NRL_INPCB 2766 #undef sotoin6pcb 2767 #undef in6pcb 2768 #undef in6p_icmp6filt 2769 #endif 2770 2771 #ifndef HAVE_PPSRATECHECK 2772 #ifndef timersub 2773 #define timersub(tvp, uvp, vvp) \ 2774 do { \ 2775 (vvp)->tv_sec = (tvp)->tv_sec - (uvp)->tv_sec; \ 2776 (vvp)->tv_usec = (tvp)->tv_usec - (uvp)->tv_usec; \ 2777 if ((vvp)->tv_usec < 0) { \ 2778 (vvp)->tv_sec--; \ 2779 (vvp)->tv_usec += 1000000; \ 2780 } \ 2781 } while (0) 2782 #endif 2783 2784 /* 2785 * ppsratecheck(): packets (or events) per second limitation. 2786 */ 2787 static int 2788 ppsratecheck(lasttime, curpps, maxpps) 2789 struct timeval *lasttime; 2790 int *curpps; 2791 int maxpps; /* maximum pps allowed */ 2792 { 2793 struct timeval tv, delta; 2794 int s, rv; 2795 2796 s = splclock(); 2797 microtime(&tv); 2798 splx(s); 2799 2800 timersub(&tv, lasttime, &delta); 2801 2802 /* 2803 * check for 0,0 is so that the message will be seen at least once. 2804 * if more than one second have passed since the last update of 2805 * lasttime, reset the counter. 2806 * 2807 * we do increment *curpps even in *curpps < maxpps case, as some may 2808 * try to use *curpps for stat purposes as well. 2809 */ 2810 if ((lasttime->tv_sec == 0 && lasttime->tv_usec == 0) || 2811 delta.tv_sec >= 1) { 2812 *lasttime = tv; 2813 *curpps = 0; 2814 rv = 1; 2815 } else if (maxpps < 0) 2816 rv = 1; 2817 else if (*curpps < maxpps) 2818 rv = 1; 2819 else 2820 rv = 0; 2821 2822 #if 1 /*DIAGNOSTIC?*/ 2823 /* be careful about wrap-around */ 2824 if (*curpps + 1 > *curpps) 2825 *curpps = *curpps + 1; 2826 #else 2827 /* 2828 * assume that there's not too many calls to this function. 2829 * not sure if the assumption holds, as it depends on *caller's* 2830 * behavior, not the behavior of this function. 2831 * IMHO it is wrong to make assumption on the caller's behavior, 2832 * so the above #if is #if 1, not #ifdef DIAGNOSTIC. 2833 */ 2834 *curpps = *curpps + 1; 2835 #endif 2836 2837 return (rv); 2838 } 2839 #endif 2840 2841 /* 2842 * Perform rate limit check. 2843 * Returns 0 if it is okay to send the icmp6 packet. 2844 * Returns 1 if the router SHOULD NOT send this icmp6 packet due to rate 2845 * limitation. 2846 * 2847 * XXX per-destination/type check necessary? 2848 */ 2849 static int 2850 icmp6_ratelimit(dst, type, code) 2851 const struct in6_addr *dst; /* not used at this moment */ 2852 const int type; /* not used at this moment */ 2853 const int code; /* not used at this moment */ 2854 { 2855 int ret; 2856 2857 ret = 0; /*okay to send*/ 2858 2859 /* PPS limit */ 2860 if (!ppsratecheck(&icmp6errppslim_last, &icmp6errpps_count, 2861 icmp6errppslim)) { 2862 /* The packet is subject to rate limit */ 2863 ret++; 2864 } 2865 2866 return ret; 2867 } 2868