icmp6.c revision 62587
1/* $FreeBSD: head/sys/netinet6/icmp6.c 62587 2000-07-04 16:35:15Z itojun $ */ 2/* $KAME: icmp6.c,v 1.119 2000/07/03 14:16:46 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/mbuf.h> 75#include <sys/protosw.h> 76#include <sys/socket.h> 77#include <sys/socketvar.h> 78#include <sys/time.h> 79#include <sys/kernel.h> 80#include <sys/syslog.h> 81#include <sys/domain.h> 82 83#include <net/if.h> 84#include <net/route.h> 85#include <net/if_dl.h> 86#include <net/if_types.h> 87 88#include <netinet/in.h> 89#include <netinet/in_var.h> 90#include <netinet/ip6.h> 91#include <netinet6/ip6_var.h> 92#include <netinet/icmp6.h> 93#include <netinet6/mld6_var.h> 94#include <netinet/in_pcb.h> 95#include <netinet6/in6_pcb.h> 96#include <netinet6/nd6.h> 97#include <netinet6/in6_ifattach.h> 98#include <netinet6/ip6protosw.h> 99 100#ifdef IPSEC 101#include <netinet6/ipsec.h> 102#ifdef INET6 103#include <netinet6/ipsec6.h> 104#endif 105#include <netkey/key.h> 106#endif 107 108#include "faith.h" 109 110#include <net/net_osdep.h> 111 112extern struct domain inet6domain; 113extern struct ip6protosw inet6sw[]; 114extern u_char ip6_protox[]; 115 116struct icmp6stat icmp6stat; 117 118extern struct inpcbhead ripcb; 119extern struct timeval icmp6errratelim; 120static struct timeval icmp6errratelim_last; 121extern int icmp6errppslim; 122static int icmp6errpps_count = 0; 123extern int icmp6_nodeinfo; 124 125static void icmp6_errcount __P((struct icmp6errstat *, int, int)); 126static int icmp6_rip6_input __P((struct mbuf **, int)); 127static void icmp6_mtudisc_update __P((struct in6_addr *, struct icmp6_hdr *, 128 struct mbuf *)); 129static int icmp6_ratelimit __P((const struct in6_addr *, const int, const int)); 130static const char *icmp6_redirect_diag __P((struct in6_addr *, 131 struct in6_addr *, struct in6_addr *)); 132#ifndef HAVE_RATECHECK 133static int ratecheck __P((struct timeval *, struct timeval *)); 134#endif 135static struct mbuf *ni6_input __P((struct mbuf *, int)); 136static struct mbuf *ni6_nametodns __P((const char *, int, int)); 137static int ni6_dnsmatch __P((const char *, int, const char *, int)); 138static int ni6_addrs __P((struct icmp6_nodeinfo *, struct mbuf *, 139 struct ifnet **)); 140static int ni6_store_addrs __P((struct icmp6_nodeinfo *, struct icmp6_nodeinfo *, 141 struct ifnet *, int)); 142 143#ifdef COMPAT_RFC1885 144static struct route_in6 icmp6_reflect_rt; 145#endif 146 147void 148icmp6_init() 149{ 150 mld6_init(); 151} 152 153static void 154icmp6_errcount(stat, type, code) 155 struct icmp6errstat *stat; 156 int type, code; 157{ 158 switch(type) { 159 case ICMP6_DST_UNREACH: 160 switch (code) { 161 case ICMP6_DST_UNREACH_NOROUTE: 162 stat->icp6errs_dst_unreach_noroute++; 163 return; 164 case ICMP6_DST_UNREACH_ADMIN: 165 stat->icp6errs_dst_unreach_admin++; 166 return; 167 case ICMP6_DST_UNREACH_BEYONDSCOPE: 168 stat->icp6errs_dst_unreach_beyondscope++; 169 return; 170 case ICMP6_DST_UNREACH_ADDR: 171 stat->icp6errs_dst_unreach_addr++; 172 return; 173 case ICMP6_DST_UNREACH_NOPORT: 174 stat->icp6errs_dst_unreach_noport++; 175 return; 176 } 177 break; 178 case ICMP6_PACKET_TOO_BIG: 179 stat->icp6errs_packet_too_big++; 180 return; 181 case ICMP6_TIME_EXCEEDED: 182 switch(code) { 183 case ICMP6_TIME_EXCEED_TRANSIT: 184 stat->icp6errs_time_exceed_transit++; 185 return; 186 case ICMP6_TIME_EXCEED_REASSEMBLY: 187 stat->icp6errs_time_exceed_reassembly++; 188 return; 189 } 190 break; 191 case ICMP6_PARAM_PROB: 192 switch(code) { 193 case ICMP6_PARAMPROB_HEADER: 194 stat->icp6errs_paramprob_header++; 195 return; 196 case ICMP6_PARAMPROB_NEXTHEADER: 197 stat->icp6errs_paramprob_nextheader++; 198 return; 199 case ICMP6_PARAMPROB_OPTION: 200 stat->icp6errs_paramprob_option++; 201 return; 202 } 203 break; 204 case ND_REDIRECT: 205 stat->icp6errs_redirect++; 206 return; 207 } 208 stat->icp6errs_unknown++; 209} 210 211/* 212 * Generate an error packet of type error in response to bad IP6 packet. 213 */ 214void 215icmp6_error(m, type, code, param) 216 struct mbuf *m; 217 int type, code, param; 218{ 219 struct ip6_hdr *oip6, *nip6; 220 struct icmp6_hdr *icmp6; 221 u_int preplen; 222 int off; 223 int nxt; 224 225 icmp6stat.icp6s_error++; 226 227 /* count per-type-code statistics */ 228 icmp6_errcount(&icmp6stat.icp6s_outerrhist, type, code); 229 230#ifdef M_DECRYPTED /*not openbsd*/ 231 if (m->m_flags & M_DECRYPTED) { 232 icmp6stat.icp6s_canterror++; 233 goto freeit; 234 } 235#endif 236 237#ifndef PULLDOWN_TEST 238 IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), ); 239#else 240 if (m->m_len < sizeof(struct ip6_hdr)) { 241 m = m_pullup(m, sizeof(struct ip6_hdr)); 242 if (m == NULL) 243 return; 244 } 245#endif 246 oip6 = mtod(m, struct ip6_hdr *); 247 248 /* 249 * Multicast destination check. For unrecognized option errors, 250 * this check has already done in ip6_unknown_opt(), so we can 251 * check only for other errors. 252 */ 253 if ((m->m_flags & (M_BCAST|M_MCAST) || 254 IN6_IS_ADDR_MULTICAST(&oip6->ip6_dst)) && 255 (type != ICMP6_PACKET_TOO_BIG && 256 (type != ICMP6_PARAM_PROB || 257 code != ICMP6_PARAMPROB_OPTION))) 258 goto freeit; 259 260 /* Source address check. XXX: the case of anycast source? */ 261 if (IN6_IS_ADDR_UNSPECIFIED(&oip6->ip6_src) || 262 IN6_IS_ADDR_MULTICAST(&oip6->ip6_src)) 263 goto freeit; 264 265 /* 266 * If we are about to send ICMPv6 against ICMPv6 error/redirect, 267 * don't do it. 268 */ 269 nxt = -1; 270 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt); 271 if (off >= 0 && nxt == IPPROTO_ICMPV6) { 272 struct icmp6_hdr *icp; 273 274#ifndef PULLDOWN_TEST 275 IP6_EXTHDR_CHECK(m, 0, off + sizeof(struct icmp6_hdr), ); 276 icp = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 277#else 278 IP6_EXTHDR_GET(icp, struct icmp6_hdr *, m, off, 279 sizeof(*icp)); 280 if (icp == NULL) { 281 icmp6stat.icp6s_tooshort++; 282 return; 283 } 284#endif 285 if (icp->icmp6_type < ICMP6_ECHO_REQUEST || 286 icp->icmp6_type == ND_REDIRECT) { 287 /* 288 * ICMPv6 error 289 * Special case: for redirect (which is 290 * informational) we must not send icmp6 error. 291 */ 292 icmp6stat.icp6s_canterror++; 293 goto freeit; 294 } else { 295 /* ICMPv6 informational - send the error */ 296 } 297 } else { 298 /* non-ICMPv6 - send the error */ 299 } 300 301 oip6 = mtod(m, struct ip6_hdr *); /* adjust pointer */ 302 303 /* Finally, do rate limitation check. */ 304 if (icmp6_ratelimit(&oip6->ip6_src, type, code)) { 305 icmp6stat.icp6s_toofreq++; 306 goto freeit; 307 } 308 309 /* 310 * OK, ICMP6 can be generated. 311 */ 312 313 if (m->m_pkthdr.len >= ICMPV6_PLD_MAXLEN) 314 m_adj(m, ICMPV6_PLD_MAXLEN - m->m_pkthdr.len); 315 316 preplen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 317 M_PREPEND(m, preplen, M_DONTWAIT); 318 if (m && m->m_len < preplen) 319 m = m_pullup(m, preplen); 320 if (m == NULL) { 321 printf("ENOBUFS in icmp6_error %d\n", __LINE__); 322 return; 323 } 324 325 nip6 = mtod(m, struct ip6_hdr *); 326 nip6->ip6_src = oip6->ip6_src; 327 nip6->ip6_dst = oip6->ip6_dst; 328 329 if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_src)) 330 oip6->ip6_src.s6_addr16[1] = 0; 331 if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_dst)) 332 oip6->ip6_dst.s6_addr16[1] = 0; 333 334 icmp6 = (struct icmp6_hdr *)(nip6 + 1); 335 icmp6->icmp6_type = type; 336 icmp6->icmp6_code = code; 337 icmp6->icmp6_pptr = htonl((u_int32_t)param); 338 339 icmp6stat.icp6s_outhist[type]++; 340 icmp6_reflect(m, sizeof(struct ip6_hdr)); /*header order: IPv6 - ICMPv6*/ 341 342 return; 343 344 freeit: 345 /* 346 * If we can't tell wheter or not we can generate ICMP6, free it. 347 */ 348 m_freem(m); 349} 350 351/* 352 * Process a received ICMP6 message. 353 */ 354int 355icmp6_input(mp, offp, proto) 356 struct mbuf **mp; 357 int *offp, proto; 358{ 359 struct mbuf *m = *mp, *n; 360 struct ip6_hdr *ip6, *nip6; 361 struct icmp6_hdr *icmp6, *nicmp6; 362 int off = *offp; 363 int icmp6len = m->m_pkthdr.len - *offp; 364 int code, sum, noff; 365 struct sockaddr_in6 icmp6src; 366 367#ifndef PULLDOWN_TEST 368 IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_hdr), IPPROTO_DONE); 369 /* m might change if M_LOOP. So, call mtod after this */ 370#endif 371 372 /* 373 * Locate icmp6 structure in mbuf, and check 374 * that not corrupted and of at least minimum length 375 */ 376 377 ip6 = mtod(m, struct ip6_hdr *); 378 if (icmp6len < sizeof(struct icmp6_hdr)) { 379 icmp6stat.icp6s_tooshort++; 380 goto freeit; 381 } 382 383 /* 384 * calculate the checksum 385 */ 386#ifndef PULLDOWN_TEST 387 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off); 388#else 389 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 390 if (icmp6 == NULL) { 391 icmp6stat.icp6s_tooshort++; 392 return IPPROTO_DONE; 393 } 394#endif 395 code = icmp6->icmp6_code; 396 397 if ((sum = in6_cksum(m, IPPROTO_ICMPV6, off, icmp6len)) != 0) { 398 log(LOG_ERR, 399 "ICMP6 checksum error(%d|%x) %s\n", 400 icmp6->icmp6_type, 401 sum, 402 ip6_sprintf(&ip6->ip6_src)); 403 icmp6stat.icp6s_checksum++; 404 goto freeit; 405 } 406 407#if defined(NFAITH) && 0 < NFAITH 408 if (m->m_pkthdr.rcvif && m->m_pkthdr.rcvif->if_type == IFT_FAITH) { 409 /* 410 * Deliver very specific ICMP6 type only. 411 * This is important to deilver TOOBIG. Otherwise PMTUD 412 * will not work. 413 */ 414 switch (icmp6->icmp6_type) { 415 case ICMP6_DST_UNREACH: 416 case ICMP6_PACKET_TOO_BIG: 417 case ICMP6_TIME_EXCEEDED: 418 break; 419 default: 420 goto freeit; 421 } 422 } 423#endif 424 425#ifdef IPSEC 426 /* drop it if it does not match the default policy */ 427 if (ipsec6_in_reject(m, NULL)) { 428 ipsecstat.in_polvio++; 429 goto freeit; 430 } 431#endif 432 433 icmp6stat.icp6s_inhist[icmp6->icmp6_type]++; 434 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_msg); 435 if (icmp6->icmp6_type < ICMP6_INFOMSG_MASK) 436 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_error); 437 438 switch (icmp6->icmp6_type) { 439 440 case ICMP6_DST_UNREACH: 441 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_dstunreach); 442 switch (code) { 443 case ICMP6_DST_UNREACH_NOROUTE: 444 code = PRC_UNREACH_NET; 445 break; 446 case ICMP6_DST_UNREACH_ADMIN: 447 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_adminprohib); 448 code = PRC_UNREACH_PROTOCOL; /* is this a good code? */ 449 break; 450 case ICMP6_DST_UNREACH_ADDR: 451 code = PRC_HOSTDEAD; 452 break; 453#ifdef COMPAT_RFC1885 454 case ICMP6_DST_UNREACH_NOTNEIGHBOR: 455 code = PRC_UNREACH_SRCFAIL; 456 break; 457#else 458 case ICMP6_DST_UNREACH_BEYONDSCOPE: 459 /* I mean "source address was incorrect." */ 460 code = PRC_PARAMPROB; 461 break; 462#endif 463 case ICMP6_DST_UNREACH_NOPORT: 464 code = PRC_UNREACH_PORT; 465 break; 466 default: 467 goto badcode; 468 } 469 goto deliver; 470 break; 471 472 case ICMP6_PACKET_TOO_BIG: 473 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_pkttoobig); 474 if (code != 0) 475 goto badcode; 476 477 code = PRC_MSGSIZE; 478 479 /* 480 * Updating the path MTU will be done after examining 481 * intermediate extension headers. 482 */ 483 goto deliver; 484 break; 485 486 case ICMP6_TIME_EXCEEDED: 487 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_timeexceed); 488 switch (code) { 489 case ICMP6_TIME_EXCEED_TRANSIT: 490 case ICMP6_TIME_EXCEED_REASSEMBLY: 491 code += PRC_TIMXCEED_INTRANS; 492 break; 493 default: 494 goto badcode; 495 } 496 goto deliver; 497 break; 498 499 case ICMP6_PARAM_PROB: 500 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_paramprob); 501 switch (code) { 502 case ICMP6_PARAMPROB_NEXTHEADER: 503 code = PRC_UNREACH_PROTOCOL; 504 break; 505 case ICMP6_PARAMPROB_HEADER: 506 case ICMP6_PARAMPROB_OPTION: 507 code = PRC_PARAMPROB; 508 break; 509 default: 510 goto badcode; 511 } 512 goto deliver; 513 break; 514 515 case ICMP6_ECHO_REQUEST: 516 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echo); 517 if (code != 0) 518 goto badcode; 519 if ((n = m_copy(m, 0, M_COPYALL)) == NULL) { 520 /* Give up remote */ 521 break; 522 } 523 if ((n->m_flags & M_EXT) != 0 524 || n->m_len < off + sizeof(struct icmp6_hdr)) { 525 struct mbuf *n0 = n; 526 const int maxlen = sizeof(*nip6) + sizeof(*nicmp6); 527 528 /* 529 * Prepare an internal mbuf. m_pullup() doesn't 530 * always copy the length we specified. 531 */ 532 if (maxlen >= MCLBYTES) { 533#ifdef DIAGNOSTIC 534 printf("MCLBYTES too small\n"); 535#endif 536 /* Give up remote */ 537 m_freem(n0); 538 break; 539 } 540 MGETHDR(n, M_DONTWAIT, n0->m_type); 541 if (n && maxlen >= MHLEN) { 542 MCLGET(n, M_DONTWAIT); 543 if ((n->m_flags & M_EXT) == 0) { 544 m_free(n); 545 n = NULL; 546 } 547 } 548 if (n == NULL) { 549 /* Give up remote */ 550 m_freem(n0); 551 break; 552 } 553 M_COPY_PKTHDR(n, n0); 554 /* 555 * Copy IPv6 and ICMPv6 only. 556 */ 557 nip6 = mtod(n, struct ip6_hdr *); 558 bcopy(ip6, nip6, sizeof(struct ip6_hdr)); 559 nicmp6 = (struct icmp6_hdr *)(nip6 + 1); 560 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr)); 561 noff = sizeof(struct ip6_hdr); 562 n->m_pkthdr.len = n->m_len = 563 noff + sizeof(struct icmp6_hdr); 564 /* 565 * Adjust mbuf. ip6_plen will be adjusted in 566 * ip6_output(). 567 */ 568 m_adj(n0, off + sizeof(struct icmp6_hdr)); 569 n->m_pkthdr.len += n0->m_pkthdr.len; 570 n->m_next = n0; 571 n0->m_flags &= ~M_PKTHDR; 572 } else { 573 nip6 = mtod(n, struct ip6_hdr *); 574 nicmp6 = (struct icmp6_hdr *)((caddr_t)nip6 + off); 575 noff = off; 576 } 577 nicmp6->icmp6_type = ICMP6_ECHO_REPLY; 578 nicmp6->icmp6_code = 0; 579 if (n) { 580 icmp6stat.icp6s_reflect++; 581 icmp6stat.icp6s_outhist[ICMP6_ECHO_REPLY]++; 582 icmp6_reflect(n, noff); 583 } 584 break; 585 586 case ICMP6_ECHO_REPLY: 587 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echoreply); 588 if (code != 0) 589 goto badcode; 590 break; 591 592 case MLD6_LISTENER_QUERY: 593 case MLD6_LISTENER_REPORT: 594 if (icmp6len < sizeof(struct mld6_hdr)) 595 goto badlen; 596 if (icmp6->icmp6_type == MLD6_LISTENER_QUERY) /* XXX: ugly... */ 597 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldquery); 598 else 599 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldreport); 600 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 601 /* give up local */ 602 mld6_input(m, off); 603 m = NULL; 604 goto freeit; 605 } 606 mld6_input(n, off); 607 /* m stays. */ 608 break; 609 610 case MLD6_LISTENER_DONE: 611 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mlddone); 612 if (icmp6len < sizeof(struct mld6_hdr)) /* necessary? */ 613 goto badlen; 614 break; /* nothing to be done in kernel */ 615 616 case MLD6_MTRACE_RESP: 617 case MLD6_MTRACE: 618 /* XXX: these two are experimental. not officially defind. */ 619 /* XXX: per-interface statistics? */ 620 break; /* just pass it to applications */ 621 622 case ICMP6_WRUREQUEST: /* ICMP6_FQDN_QUERY */ 623 { 624 enum { WRU, FQDN } mode; 625 626 if (!icmp6_nodeinfo) 627 break; 628 629 if (icmp6len == sizeof(struct icmp6_hdr) + 4) 630 mode = WRU; 631 else if (icmp6len >= sizeof(struct icmp6_nodeinfo)) 632 mode = FQDN; 633 else 634 goto badlen; 635 636#define hostnamelen strlen(hostname) 637 if (mode == FQDN) { 638#ifndef PULLDOWN_TEST 639 IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_nodeinfo), 640 IPPROTO_DONE); 641#endif 642 n = m_copy(m, 0, M_COPYALL); 643 if (n) 644 n = ni6_input(n, off); 645 /* XXX meaningless if n == NULL */ 646 noff = sizeof(struct ip6_hdr); 647 } else { 648 u_char *p; 649 int maxlen, maxhlen; 650 651 if (code != 0) 652 goto badcode; 653 maxlen = sizeof(*nip6) + sizeof(*nicmp6) + 4; 654 if (maxlen >= MCLBYTES) { 655#ifdef DIAGNOSTIC 656 printf("MCLBYTES too small\n"); 657#endif 658 /* Give up remote */ 659 break; 660 } 661 MGETHDR(n, M_DONTWAIT, m->m_type); 662 if (n && maxlen > MHLEN) { 663 MCLGET(n, M_DONTWAIT); 664 if ((n->m_flags & M_EXT) == 0) { 665 m_free(n); 666 n = NULL; 667 } 668 } 669 if (n == NULL) { 670 /* Give up remote */ 671 break; 672 } 673 n->m_len = 0; 674 maxhlen = M_TRAILINGSPACE(n) - maxlen; 675 if (maxhlen > hostnamelen) 676 maxhlen = hostnamelen; 677 /* 678 * Copy IPv6 and ICMPv6 only. 679 */ 680 nip6 = mtod(n, struct ip6_hdr *); 681 bcopy(ip6, nip6, sizeof(struct ip6_hdr)); 682 nicmp6 = (struct icmp6_hdr *)(nip6 + 1); 683 bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr)); 684 p = (u_char *)(nicmp6 + 1); 685 bzero(p, 4); 686 bcopy(hostname, p + 4, maxhlen); /*meaningless TTL*/ 687 noff = sizeof(struct ip6_hdr); 688 M_COPY_PKTHDR(n, m); /* just for recvif */ 689 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) + 690 sizeof(struct icmp6_hdr) + 4 + maxhlen; 691 nicmp6->icmp6_type = ICMP6_WRUREPLY; 692 nicmp6->icmp6_code = 0; 693 } 694#undef hostnamelen 695 if (n) { 696 icmp6stat.icp6s_reflect++; 697 icmp6stat.icp6s_outhist[ICMP6_WRUREPLY]++; 698 icmp6_reflect(n, noff); 699 } 700 break; 701 } 702 703 case ICMP6_WRUREPLY: 704 if (code != 0) 705 goto badcode; 706 break; 707 708 case ND_ROUTER_SOLICIT: 709 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routersolicit); 710 if (code != 0) 711 goto badcode; 712 if (icmp6len < sizeof(struct nd_router_solicit)) 713 goto badlen; 714 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 715 /* give up local */ 716 nd6_rs_input(m, off, icmp6len); 717 m = NULL; 718 goto freeit; 719 } 720 nd6_rs_input(n, off, icmp6len); 721 /* m stays. */ 722 break; 723 724 case ND_ROUTER_ADVERT: 725 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routeradvert); 726 if (code != 0) 727 goto badcode; 728 if (icmp6len < sizeof(struct nd_router_advert)) 729 goto badlen; 730 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 731 /* give up local */ 732 nd6_ra_input(m, off, icmp6len); 733 m = NULL; 734 goto freeit; 735 } 736 nd6_ra_input(n, off, icmp6len); 737 /* m stays. */ 738 break; 739 740 case ND_NEIGHBOR_SOLICIT: 741 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighborsolicit); 742 if (code != 0) 743 goto badcode; 744 if (icmp6len < sizeof(struct nd_neighbor_solicit)) 745 goto badlen; 746 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 747 /* give up local */ 748 nd6_ns_input(m, off, icmp6len); 749 m = NULL; 750 goto freeit; 751 } 752 nd6_ns_input(n, off, icmp6len); 753 /* m stays. */ 754 break; 755 756 case ND_NEIGHBOR_ADVERT: 757 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighboradvert); 758 if (code != 0) 759 goto badcode; 760 if (icmp6len < sizeof(struct nd_neighbor_advert)) 761 goto badlen; 762 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 763 /* give up local */ 764 nd6_na_input(m, off, icmp6len); 765 m = NULL; 766 goto freeit; 767 } 768 nd6_na_input(n, off, icmp6len); 769 /* m stays. */ 770 break; 771 772 case ND_REDIRECT: 773 icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_redirect); 774 if (code != 0) 775 goto badcode; 776 if (icmp6len < sizeof(struct nd_redirect)) 777 goto badlen; 778 if ((n = m_copym(m, 0, M_COPYALL, M_DONTWAIT)) == NULL) { 779 /* give up local */ 780 icmp6_redirect_input(m, off); 781 m = NULL; 782 goto freeit; 783 } 784 icmp6_redirect_input(n, off); 785 /* m stays. */ 786 break; 787 788 case ICMP6_ROUTER_RENUMBERING: 789 if (code != ICMP6_ROUTER_RENUMBERING_COMMAND && 790 code != ICMP6_ROUTER_RENUMBERING_RESULT) 791 goto badcode; 792 if (icmp6len < sizeof(struct icmp6_router_renum)) 793 goto badlen; 794 break; 795 796 default: 797 printf("icmp6_input: unknown type %d(src=%s, dst=%s, ifid=%d)\n", 798 icmp6->icmp6_type, ip6_sprintf(&ip6->ip6_src), 799 ip6_sprintf(&ip6->ip6_dst), 800 m->m_pkthdr.rcvif ? m->m_pkthdr.rcvif->if_index : 0); 801 if (icmp6->icmp6_type < ICMP6_ECHO_REQUEST) { 802 /* ICMPv6 error: MUST deliver it by spec... */ 803 code = PRC_NCMDS; 804 /* deliver */ 805 } else { 806 /* ICMPv6 informational: MUST not deliver */ 807 break; 808 } 809 deliver: 810 if (icmp6len < sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr)) { 811 icmp6stat.icp6s_tooshort++; 812 goto freeit; 813 } 814#ifndef PULLDOWN_TEST 815 IP6_EXTHDR_CHECK(m, off, 816 sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr), 817 IPPROTO_DONE); 818 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 819#else 820 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, 821 sizeof(*icmp6) + sizeof(struct ip6_hdr)); 822 if (icmp6 == NULL) { 823 icmp6stat.icp6s_tooshort++; 824 return IPPROTO_DONE; 825 } 826#endif 827 bzero(&icmp6src, sizeof(icmp6src)); 828 icmp6src.sin6_len = sizeof(struct sockaddr_in6); 829 icmp6src.sin6_family = AF_INET6; 830 icmp6src.sin6_addr = ((struct ip6_hdr *)(icmp6 + 1))->ip6_dst; 831 832 /* Detect the upper level protocol */ 833 { 834 void (*ctlfunc) __P((int, struct sockaddr *, void *)); 835 struct ip6_hdr *eip6 = (struct ip6_hdr *)(icmp6 + 1); 836 u_int8_t nxt = eip6->ip6_nxt; 837 int eoff = off + sizeof(struct icmp6_hdr) + 838 sizeof(struct ip6_hdr); 839 struct ip6ctlparam ip6cp; 840 struct in6_addr *finaldst = NULL; 841 int icmp6type = icmp6->icmp6_type; 842 struct ip6_frag *fh; 843 struct ip6_rthdr *rth; 844 struct ip6_rthdr0 *rth0; 845 int rthlen; 846 847 while (1) { /* XXX: should avoid inf. loop explicitly? */ 848 struct ip6_ext *eh; 849 850 switch(nxt) { 851 case IPPROTO_HOPOPTS: 852 case IPPROTO_DSTOPTS: 853 case IPPROTO_AH: 854#ifndef PULLDOWN_TEST 855 IP6_EXTHDR_CHECK(m, 0, eoff + 856 sizeof(struct ip6_ext), 857 IPPROTO_DONE); 858 eh = (struct ip6_ext *)(mtod(m, caddr_t) 859 + eoff); 860#else 861 IP6_EXTHDR_GET(eh, struct ip6_ext *, m, 862 eoff, sizeof(*eh)); 863 if (eh == NULL) { 864 icmp6stat.icp6s_tooshort++; 865 return IPPROTO_DONE; 866 } 867#endif 868 869 if (nxt == IPPROTO_AH) 870 eoff += (eh->ip6e_len + 2) << 2; 871 else 872 eoff += (eh->ip6e_len + 1) << 3; 873 nxt = eh->ip6e_nxt; 874 break; 875 case IPPROTO_ROUTING: 876 /* 877 * When the erroneous packet contains a 878 * routing header, we should examine the 879 * header to determine the final destination. 880 * Otherwise, we can't properly update 881 * information that depends on the final 882 * destination (e.g. path MTU). 883 */ 884#ifndef PULLDOWN_TEST 885 IP6_EXTHDR_CHECK(m, 0, eoff + sizeof(*rth), 886 IPPROTO_DONE); 887 rth = (struct ip6_rthdr *)(mtod(m, caddr_t) 888 + eoff); 889#else 890 IP6_EXTHDR_GET(rth, struct ip6_rthdr *, m, 891 eoff, sizeof(*rth)); 892 if (rth == NULL) { 893 icmp6stat.icp6s_tooshort++; 894 return IPPROTO_DONE; 895 } 896#endif 897 rthlen = (rth->ip6r_len + 1) << 3; 898 /* 899 * XXX: currently there is no 900 * officially defined type other 901 * than type-0. 902 * Note that if the segment left field 903 * is 0, all intermediate hops must 904 * have been passed. 905 */ 906 if (rth->ip6r_segleft && 907 rth->ip6r_type == IPV6_RTHDR_TYPE_0) { 908 int hops; 909 910#ifndef PULLDOWN_TEST 911 IP6_EXTHDR_CHECK(m, 0, eoff + rthlen, 912 IPPROTO_DONE); 913 rth0 = (struct ip6_rthdr0 *)(mtod(m, caddr_t) + eoff); 914#else 915 IP6_EXTHDR_GET(rth0, 916 struct ip6_rthdr0 *, m, 917 eoff, rthlen); 918 if (rth0 == NULL) { 919 icmp6stat.icp6s_tooshort++; 920 return IPPROTO_DONE; 921 } 922#endif 923 /* just ignore a bogus header */ 924 if ((rth0->ip6r0_len % 2) == 0 && 925 (hops = rth0->ip6r0_len/2)) 926 finaldst = (struct in6_addr *)(rth0 + 1) + (hops - 1); 927 } 928 eoff += rthlen; 929 nxt = rth->ip6r_nxt; 930 break; 931 case IPPROTO_FRAGMENT: 932#ifndef PULLDOWN_TEST 933 IP6_EXTHDR_CHECK(m, 0, eoff + 934 sizeof(struct ip6_frag), 935 IPPROTO_DONE); 936 fh = (struct ip6_frag *)(mtod(m, caddr_t) 937 + eoff); 938#else 939 IP6_EXTHDR_GET(fh, struct ip6_frag *, m, 940 eoff, sizeof(*fh)); 941 if (fh == NULL) { 942 icmp6stat.icp6s_tooshort++; 943 return IPPROTO_DONE; 944 } 945#endif 946 /* 947 * Data after a fragment header is meaningless 948 * unless it is the first fragment, but 949 * we'll go to the notify label for path MTU 950 * discovery. 951 */ 952 if (fh->ip6f_offlg & IP6F_OFF_MASK) 953 goto notify; 954 955 eoff += sizeof(struct ip6_frag); 956 nxt = fh->ip6f_nxt; 957 break; 958 default: 959 /* 960 * This case includes ESP and the No Next 961 * Header. In such cases going to the notify 962 * label does not have any meaning 963 * (i.e. ctlfunc will be NULL), but we go 964 * anyway since we might have to update 965 * path MTU information. 966 */ 967 goto notify; 968 } 969 } 970 notify: 971#ifndef PULLDOWN_TEST 972 icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off); 973#else 974 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, 975 sizeof(*icmp6) + sizeof(struct ip6_hdr)); 976 if (icmp6 == NULL) { 977 icmp6stat.icp6s_tooshort++; 978 return IPPROTO_DONE; 979 } 980#endif 981 if (icmp6type == ICMP6_PACKET_TOO_BIG) { 982 if (finaldst == NULL) 983 finaldst = &((struct ip6_hdr *)(icmp6 + 1))->ip6_dst; 984 icmp6_mtudisc_update(finaldst, icmp6, m); 985 } 986 987 ctlfunc = (void (*) __P((int, struct sockaddr *, void *))) 988 (inet6sw[ip6_protox[nxt]].pr_ctlinput); 989 if (ctlfunc) { 990 ip6cp.ip6c_m = m; 991 ip6cp.ip6c_ip6 = (struct ip6_hdr *)(icmp6 + 1); 992 ip6cp.ip6c_off = eoff; 993 (*ctlfunc)(code, (struct sockaddr *)&icmp6src, &ip6cp); 994 } 995 } 996 break; 997 998 badcode: 999 icmp6stat.icp6s_badcode++; 1000 break; 1001 1002 badlen: 1003 icmp6stat.icp6s_badlen++; 1004 break; 1005 } 1006 1007#ifdef HAVE_NRL_INPCB 1008 rip6_input(&m, offp, IPPROTO_ICMPV6); 1009#else 1010 icmp6_rip6_input(&m, *offp); 1011#endif 1012 return IPPROTO_DONE; 1013 1014 freeit: 1015 m_freem(m); 1016 return IPPROTO_DONE; 1017} 1018 1019static void 1020icmp6_mtudisc_update(dst, icmp6, m) 1021 struct in6_addr *dst; 1022 struct icmp6_hdr *icmp6;/* we can assume the validity of the pointer */ 1023 struct mbuf *m; /* currently unused but added for scoped addrs */ 1024{ 1025 u_int mtu = ntohl(icmp6->icmp6_mtu); 1026 struct rtentry *rt = NULL; 1027 struct sockaddr_in6 sin6; 1028 1029 bzero(&sin6, sizeof(sin6)); 1030 sin6.sin6_family = PF_INET6; 1031 sin6.sin6_len = sizeof(struct sockaddr_in6); 1032 sin6.sin6_addr = *dst; 1033 /* sin6.sin6_scope_id = XXX: should be set if DST is a scoped addr */ 1034 rt = rtalloc1((struct sockaddr *)&sin6, 0, 1035 RTF_CLONING | RTF_PRCLONING); 1036 1037 if (rt && (rt->rt_flags & RTF_HOST) 1038 && !(rt->rt_rmx.rmx_locks & RTV_MTU)) { 1039 if (mtu < IPV6_MMTU) { 1040 /* xxx */ 1041 rt->rt_rmx.rmx_locks |= RTV_MTU; 1042 } else if (mtu < rt->rt_ifp->if_mtu && 1043 rt->rt_rmx.rmx_mtu > mtu) { 1044 rt->rt_rmx.rmx_mtu = mtu; 1045 } 1046 } 1047 if (rt) 1048 RTFREE(rt); 1049} 1050 1051/* 1052 * Process a Node Information Query packet, (roughly) based on 1053 * draft-ietf-ipngwg-icmp-name-lookups-05. 1054 * 1055 * Spec incompatibilities: 1056 * - IPv6 Subject address handling 1057 * - IPv4 Subject address handling support missing 1058 * - Proxy reply (answer even if it's not for me) 1059 * - "Supported Qtypes" support missing 1060 * - joins NI group address at in6_ifattach() time only, does not cope 1061 * with hostname changes by sethostname(3) 1062 */ 1063#define hostnamelen strlen(hostname) 1064#ifndef offsetof /* XXX */ 1065#define offsetof(type, member) ((size_t)(&((type *)0)->member)) 1066#endif 1067static struct mbuf * 1068ni6_input(m, off) 1069 struct mbuf *m; 1070 int off; 1071{ 1072 struct icmp6_nodeinfo *ni6, *nni6; 1073 struct mbuf *n = NULL; 1074 u_int16_t qtype; 1075 int subjlen; 1076 int replylen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo); 1077 struct ni_reply_fqdn *fqdn; 1078 int addrs; /* for NI_QTYPE_NODEADDR */ 1079 struct ifnet *ifp = NULL; /* for NI_QTYPE_NODEADDR */ 1080 struct sockaddr_in6 sin6; 1081 struct ip6_hdr *ip6; 1082 int oldfqdn = 0; /* if 1, return pascal string (03 draft) */ 1083 char *subj; 1084 1085 ip6 = mtod(m, struct ip6_hdr *); 1086#ifndef PULLDOWN_TEST 1087 ni6 = (struct icmp6_nodeinfo *)(mtod(m, caddr_t) + off); 1088#else 1089 IP6_EXTHDR_GET(ni6, struct icmp6_nodeinfo *, m, off, sizeof(*ni6)); 1090 if (ni6 == NULL) { 1091 /* m is already reclaimed */ 1092 return NULL; 1093 } 1094#endif 1095 1096 /* 1097 * Validate IPv6 destination address. 1098 * 1099 * We accept packets with the following IPv6 destination address: 1100 * - Responder's unicast/anycast address, 1101 * - link-local multicast address 1102 * This is a violation to last paragraph in icmp-name-lookups-05 1103 * page 4, which restricts IPv6 destination address of a query to: 1104 * - Responder's unicast/anycast address, 1105 * - NI group address for a name belongs to the Responder, or 1106 * - NI group address for a name for which the Responder is providing 1107 * proxy service. 1108 * (note: NI group address is a link-local multicast address) 1109 * 1110 * We allow any link-local multicast address, since "ping6 -w ff02::1" 1111 * has been really useful for us debugging our network. Also this is 1112 * still questionable if the restriction in spec buy us security at all, 1113 * since RFC2463 permits echo packet to multicast destination. 1114 * Even if we forbid NI query to ff02::1, we can effectively get the 1115 * same result as "ping6 -w ff02::1" by the following steps: 1116 * - run "ping6 ff02::1", then 1117 * - run "ping6 -w" for all addresses replied. 1118 */ 1119 bzero(&sin6, sizeof(sin6)); 1120 sin6.sin6_family = AF_INET6; 1121 sin6.sin6_len = sizeof(struct sockaddr_in6); 1122 bcopy(&ip6->ip6_dst, &sin6.sin6_addr, sizeof(sin6.sin6_addr)); 1123 /* XXX scopeid */ 1124 if (ifa_ifwithaddr((struct sockaddr *)&sin6)) 1125 ; /*unicast/anycast, fine*/ 1126 else if (IN6_IS_ADDR_MC_LINKLOCAL(&sin6.sin6_addr)) 1127 ; /*violates spec slightly, see above*/ 1128 else 1129 goto bad; 1130 1131 /* guess reply length */ 1132 qtype = ntohs(ni6->ni_qtype); 1133 switch (qtype) { 1134 case NI_QTYPE_NOOP: 1135 break; /* no reply data */ 1136 case NI_QTYPE_SUPTYPES: 1137 goto bad; /* xxx: to be implemented */ 1138 break; 1139 case NI_QTYPE_FQDN: 1140 /* XXX will append a mbuf */ 1141 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1142 break; 1143 case NI_QTYPE_NODEADDR: 1144 addrs = ni6_addrs(ni6, m, &ifp); 1145 if ((replylen += addrs * sizeof(struct in6_addr)) > MCLBYTES) 1146 replylen = MCLBYTES; /* XXX: we'll truncate later */ 1147 break; 1148 default: 1149 /* 1150 * XXX: We must return a reply with the ICMP6 code 1151 * `unknown Qtype' in this case. However we regard the case 1152 * as an FQDN query for backward compatibility. 1153 * Older versions set a random value to this field, 1154 * so it rarely varies in the defined qtypes. 1155 * But the mechanism is not reliable... 1156 * maybe we should obsolete older versions. 1157 */ 1158 qtype = NI_QTYPE_FQDN; 1159 /* XXX will append a mbuf */ 1160 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_namelen); 1161 oldfqdn++; 1162 break; 1163 } 1164 1165 /* validate query Subject field. */ 1166 subjlen = m->m_pkthdr.len - off - sizeof(struct icmp6_nodeinfo); 1167 switch (qtype) { 1168 case NI_QTYPE_NOOP: 1169 case NI_QTYPE_SUPTYPES: 1170 if (subjlen != 0) 1171 goto bad; 1172 break; 1173 1174 case NI_QTYPE_FQDN: 1175 case NI_QTYPE_NODEADDR: 1176 switch (ni6->ni_code) { 1177 case ICMP6_NI_SUBJ_IPV6: 1178#if ICMP6_NI_SUBJ_IPV6 != 0 1179 case 0: 1180#endif 1181 /* 1182 * backward compatibility - try to accept 03 draft 1183 * format, where no Subject is present. 1184 */ 1185 if (subjlen == 0) { 1186 oldfqdn++; 1187 break; 1188 } 1189 1190 if (subjlen != sizeof(sin6.sin6_addr)) 1191 goto bad; 1192 1193 /* 1194 * Validate Subject address. 1195 * 1196 * Not sure what exactly does "address belongs to the 1197 * node" mean in the spec, is it just unicast, or what? 1198 * 1199 * At this moment we consider Subject address as 1200 * "belong to the node" if the Subject address equals 1201 * to the IPv6 destination address; validation for 1202 * IPv6 destination address should have done enough 1203 * check for us. 1204 * 1205 * We do not do proxy at this moment. 1206 */ 1207 /* m_pulldown instead of copy? */ 1208 m_copydata(m, off + sizeof(struct icmp6_nodeinfo), 1209 subjlen, (caddr_t)&sin6.sin6_addr); 1210 /* XXX kame scope hack */ 1211 if (IN6_IS_SCOPE_LINKLOCAL(&sin6.sin6_addr)) { 1212#ifdef FAKE_LOOPBACK_IF 1213 if ((m->m_flags & M_PKTHDR) != 0 && 1214 m->m_pkthdr.rcvif) { 1215 sin6.sin6_addr.s6_addr16[1] = 1216 htons(m->m_pkthdr.rcvif->if_index); 1217 } 1218#else 1219 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) { 1220 sin6.sin6_addr.s6_addr16[1] = 1221 ip6->ip6_dst.s6_addr16[1]; 1222 } 1223#endif 1224 } 1225 if (IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, &sin6.sin6_addr)) 1226 break; 1227 /* 1228 * XXX if we are to allow other cases, we should really 1229 * be careful about scope here. 1230 * basically, we should disallow queries toward IPv6 1231 * destination X with subject Y, if scope(X) > scope(Y). 1232 * if we allow scope(X) > scope(Y), it will result in 1233 * information leakage across scope boundary. 1234 */ 1235 goto bad; 1236 1237 case ICMP6_NI_SUBJ_FQDN: 1238 /* 1239 * Validate Subject name with gethostname(3). 1240 * 1241 * The behavior may need some debate, since: 1242 * - we are not sure if the node has FQDN as 1243 * hostname (returned by gethostname(3)). 1244 * - the code does wildcard match for truncated names. 1245 * however, we are not sure if we want to perform 1246 * wildcard match, if gethostname(3) side has 1247 * truncated hostname. 1248 */ 1249 n = ni6_nametodns(hostname, hostnamelen, 0); 1250 if (!n || n->m_next || n->m_len == 0) 1251 goto bad; 1252 IP6_EXTHDR_GET(subj, char *, m, 1253 off + sizeof(struct icmp6_nodeinfo), subjlen); 1254 if (subj == NULL) 1255 goto bad; 1256 if (!ni6_dnsmatch(subj, subjlen, mtod(n, const char *), 1257 n->m_len)) { 1258 goto bad; 1259 } 1260 m_freem(n); 1261 n = NULL; 1262 break; 1263 1264 case ICMP6_NI_SUBJ_IPV4: /* xxx: to be implemented? */ 1265 default: 1266 goto bad; 1267 } 1268 break; 1269 1270 default: 1271 /* should never be here due to "switch (qtype)" above */ 1272 goto bad; 1273 } 1274 1275 /* allocate a mbuf to reply. */ 1276 MGETHDR(n, M_DONTWAIT, m->m_type); 1277 if (n == NULL) { 1278 m_freem(m); 1279 return(NULL); 1280 } 1281 M_COPY_PKTHDR(n, m); /* just for recvif */ 1282 if (replylen > MHLEN) { 1283 if (replylen > MCLBYTES) { 1284 /* 1285 * XXX: should we try to allocate more? But MCLBYTES is 1286 * probably much larger than IPV6_MMTU... 1287 */ 1288 goto bad; 1289 } 1290 MCLGET(n, M_DONTWAIT); 1291 if ((n->m_flags & M_EXT) == 0) { 1292 goto bad; 1293 } 1294 } 1295 n->m_pkthdr.len = n->m_len = replylen; 1296 1297 /* copy mbuf header and IPv6 + Node Information base headers */ 1298 bcopy(mtod(m, caddr_t), mtod(n, caddr_t), sizeof(struct ip6_hdr)); 1299 nni6 = (struct icmp6_nodeinfo *)(mtod(n, struct ip6_hdr *) + 1); 1300 bcopy((caddr_t)ni6, (caddr_t)nni6, sizeof(struct icmp6_nodeinfo)); 1301 1302 /* qtype dependent procedure */ 1303 switch (qtype) { 1304 case NI_QTYPE_NOOP: 1305 nni6->ni_flags = 0; 1306 break; 1307 case NI_QTYPE_SUPTYPES: 1308 goto bad; /* xxx: to be implemented */ 1309 break; 1310 case NI_QTYPE_FQDN: 1311 fqdn = (struct ni_reply_fqdn *)(mtod(n, caddr_t) + 1312 sizeof(struct ip6_hdr) + 1313 sizeof(struct icmp6_nodeinfo)); 1314 nni6->ni_flags = 0; /* XXX: meaningless TTL */ 1315 fqdn->ni_fqdn_ttl = 0; /* ditto. */ 1316 /* 1317 * XXX do we really have FQDN in variable "hostname"? 1318 */ 1319 n->m_next = ni6_nametodns(hostname, hostnamelen, oldfqdn); 1320 if (n->m_next == NULL) 1321 goto bad; 1322 /* XXX we assume that n->m_next is not a chain */ 1323 if (n->m_next->m_next != NULL) 1324 goto bad; 1325 n->m_pkthdr.len += n->m_next->m_len; 1326 break; 1327 case NI_QTYPE_NODEADDR: 1328 { 1329 int lenlim, copied; 1330 1331 if (n->m_flags & M_EXT) 1332 lenlim = MCLBYTES - sizeof(struct ip6_hdr) - 1333 sizeof(struct icmp6_nodeinfo); 1334 else 1335 lenlim = MHLEN - sizeof(struct ip6_hdr) - 1336 sizeof(struct icmp6_nodeinfo); 1337 copied = ni6_store_addrs(ni6, nni6, ifp, lenlim); 1338 /* XXX: reset mbuf length */ 1339 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) + 1340 sizeof(struct icmp6_nodeinfo) + copied; 1341 break; 1342 } 1343 default: 1344 break; /* XXX impossible! */ 1345 } 1346 1347 nni6->ni_type = ICMP6_NI_REPLY; 1348 nni6->ni_code = ICMP6_NI_SUCESS; 1349 m_freem(m); 1350 return(n); 1351 1352 bad: 1353 m_freem(m); 1354 if (n) 1355 m_freem(n); 1356 return(NULL); 1357} 1358#undef hostnamelen 1359 1360/* 1361 * make a mbuf with DNS-encoded string. no compression support. 1362 * 1363 * XXX names with less than 2 dots (like "foo" or "foo.section") will be 1364 * treated as truncated name (two \0 at the end). this is a wild guess. 1365 */ 1366static struct mbuf * 1367ni6_nametodns(name, namelen, old) 1368 const char *name; 1369 int namelen; 1370 int old; /* return pascal string if non-zero */ 1371{ 1372 struct mbuf *m; 1373 char *cp, *ep; 1374 const char *p, *q; 1375 int i, len, nterm; 1376 1377 if (old) 1378 len = namelen + 1; 1379 else 1380 len = MCLBYTES; 1381 1382 /* because MAXHOSTNAMELEN is usually 256, we use cluster mbuf */ 1383 MGET(m, M_DONTWAIT, MT_DATA); 1384 if (m && len > MLEN) { 1385 MCLGET(m, M_DONTWAIT); 1386 if ((m->m_flags & M_EXT) == 0) 1387 goto fail; 1388 } 1389 if (!m) 1390 goto fail; 1391 m->m_next = NULL; 1392 1393 if (old) { 1394 m->m_len = len; 1395 *mtod(m, char *) = namelen; 1396 bcopy(name, mtod(m, char *) + 1, namelen); 1397 return m; 1398 } else { 1399 m->m_len = 0; 1400 cp = mtod(m, char *); 1401 ep = mtod(m, char *) + M_TRAILINGSPACE(m); 1402 1403 /* if not certain about my name, return empty buffer */ 1404 if (namelen == 0) 1405 return m; 1406 1407 /* 1408 * guess if it looks like shortened hostname, or FQDN. 1409 * shortened hostname needs two trailing "\0". 1410 */ 1411 i = 0; 1412 for (p = name; p < name + namelen; p++) { 1413 if (*p && *p == '.') 1414 i++; 1415 } 1416 if (i < 2) 1417 nterm = 2; 1418 else 1419 nterm = 1; 1420 1421 p = name; 1422 while (cp < ep && p < name + namelen) { 1423 i = 0; 1424 for (q = p; q < name + namelen && *q && *q != '.'; q++) 1425 i++; 1426 /* result does not fit into mbuf */ 1427 if (cp + i + 1 >= ep) 1428 goto fail; 1429 /* DNS label length restriction, RFC1035 page 8 */ 1430 if (i >= 64) 1431 goto fail; 1432 *cp++ = i; 1433 bcopy(p, cp, i); 1434 cp += i; 1435 p = q; 1436 if (p < name + namelen && *p == '.') 1437 p++; 1438 } 1439 /* termination */ 1440 if (cp + nterm >= ep) 1441 goto fail; 1442 while (nterm-- > 0) 1443 *cp++ = '\0'; 1444 m->m_len = cp - mtod(m, char *); 1445 return m; 1446 } 1447 1448 panic("should not reach here"); 1449 /*NOTREACHED*/ 1450 1451 fail: 1452 if (m) 1453 m_freem(m); 1454 return NULL; 1455} 1456 1457/* 1458 * check if two DNS-encoded string matches. takes care of truncated 1459 * form (with \0\0 at the end). no compression support. 1460 */ 1461static int 1462ni6_dnsmatch(a, alen, b, blen) 1463 const char *a; 1464 int alen; 1465 const char *b; 1466 int blen; 1467{ 1468 const char *a0, *b0; 1469 int l; 1470 1471 /* simplest case - need validation? */ 1472 if (alen == blen && bcmp(a, b, alen) == 0) 1473 return 1; 1474 1475 a0 = a; 1476 b0 = b; 1477 1478 /* termination is mandatory */ 1479 if (alen < 2 || blen < 2) 1480 return 0; 1481 if (a0[alen - 1] != '\0' || b0[blen - 1] != '\0') 1482 return 0; 1483 alen--; 1484 blen--; 1485 1486 while (a - a0 < alen && b - b0 < blen) { 1487 if (a - a0 + 1 > alen || b - b0 + 1 > blen) 1488 return 0; 1489 1490 if ((signed char)a[0] < 0 || (signed char)b[0] < 0) 1491 return 0; 1492 /* we don't support compression yet */ 1493 if (a[0] >= 64 || b[0] >= 64) 1494 return 0; 1495 1496 /* truncated case */ 1497 if (a[0] == 0 && a - a0 == alen - 1) 1498 return 1; 1499 if (b[0] == 0 && b - b0 == blen - 1) 1500 return 1; 1501 if (a[0] == 0 || b[0] == 0) 1502 return 0; 1503 1504 if (a[0] != b[0]) 1505 return 0; 1506 l = a[0]; 1507 if (a - a0 + 1 + l > alen || b - b0 + 1 + l > blen) 1508 return 0; 1509 if (bcmp(a + 1, b + 1, l) != 0) 1510 return 0; 1511 1512 a += 1 + l; 1513 b += 1 + l; 1514 } 1515 1516 if (a - a0 == alen && b - b0 == blen) 1517 return 1; 1518 else 1519 return 0; 1520} 1521 1522/* 1523 * calculate the number of addresses to be returned in the node info reply. 1524 */ 1525static int 1526ni6_addrs(ni6, m, ifpp) 1527 struct icmp6_nodeinfo *ni6; 1528 struct mbuf *m; 1529 struct ifnet **ifpp; 1530{ 1531 register struct ifnet *ifp; 1532 register struct in6_ifaddr *ifa6; 1533 register struct ifaddr *ifa; 1534 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1535 int addrs = 0, addrsofif, iffound = 0; 1536 1537 for (ifp = TAILQ_FIRST(&ifnet); ifp; ifp = TAILQ_NEXT(ifp, if_list)) 1538 { 1539 addrsofif = 0; 1540 for (ifa = ifp->if_addrlist.tqh_first; ifa; 1541 ifa = ifa->ifa_list.tqe_next) 1542 { 1543 if (ifa->ifa_addr->sa_family != AF_INET6) 1544 continue; 1545 ifa6 = (struct in6_ifaddr *)ifa; 1546 1547 if (!(ni6->ni_flags & NI_NODEADDR_FLAG_ALL) && 1548 IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, 1549 &ifa6->ia_addr.sin6_addr)) 1550 iffound = 1; 1551 1552 /* 1553 * IPv4-mapped addresses can only be returned by a 1554 * Node Information proxy, since they represent 1555 * addresses of IPv4-only nodes, which perforce do 1556 * not implement this protocol. 1557 * [icmp-name-lookups-05] 1558 * So we don't support NI_NODEADDR_FLAG_COMPAT in 1559 * this function at this moment. 1560 */ 1561 1562 if (ifa6->ia6_flags & IN6_IFF_ANYCAST) 1563 continue; /* we need only unicast addresses */ 1564 1565 if ((ni6->ni_flags & (NI_NODEADDR_FLAG_LINKLOCAL | 1566 NI_NODEADDR_FLAG_SITELOCAL | 1567 NI_NODEADDR_FLAG_GLOBAL)) == 0) 1568 continue; 1569 1570 /* What do we have to do about ::1? */ 1571 switch(in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1572 case IPV6_ADDR_SCOPE_LINKLOCAL: 1573 if (ni6->ni_flags & NI_NODEADDR_FLAG_LINKLOCAL) 1574 addrsofif++; 1575 break; 1576 case IPV6_ADDR_SCOPE_SITELOCAL: 1577 if (ni6->ni_flags & NI_NODEADDR_FLAG_SITELOCAL) 1578 addrsofif++; 1579 break; 1580 case IPV6_ADDR_SCOPE_GLOBAL: 1581 if (ni6->ni_flags & NI_NODEADDR_FLAG_GLOBAL) 1582 addrsofif++; 1583 break; 1584 default: 1585 continue; 1586 } 1587 } 1588 if (iffound) { 1589 *ifpp = ifp; 1590 return(addrsofif); 1591 } 1592 1593 addrs += addrsofif; 1594 } 1595 1596 return(addrs); 1597} 1598 1599static int 1600ni6_store_addrs(ni6, nni6, ifp0, resid) 1601 struct icmp6_nodeinfo *ni6, *nni6; 1602 struct ifnet *ifp0; 1603 int resid; 1604{ 1605 register struct ifnet *ifp = ifp0 ? ifp0 : TAILQ_FIRST(&ifnet); 1606 register struct in6_ifaddr *ifa6; 1607 register struct ifaddr *ifa; 1608 int docopy, copied = 0; 1609 u_char *cp = (u_char *)(nni6 + 1); 1610 1611 if (ifp0 == NULL && !(ni6->ni_flags & NI_NODEADDR_FLAG_ALL)) 1612 return(0); /* needless to copy */ 1613 1614 for (; ifp; ifp = TAILQ_NEXT(ifp, if_list)) 1615 { 1616 for (ifa = ifp->if_addrlist.tqh_first; ifa; 1617 ifa = ifa->ifa_list.tqe_next) 1618 { 1619 docopy = 0; 1620 1621 if (ifa->ifa_addr->sa_family != AF_INET6) 1622 continue; 1623 ifa6 = (struct in6_ifaddr *)ifa; 1624 1625 if (ifa6->ia6_flags & IN6_IFF_ANYCAST) { 1626 /* just experimental. not in the spec. */ 1627 if (ni6->ni_flags & NI_NODEADDR_FLAG_ANYCAST) 1628 docopy = 1; 1629 else 1630 continue; 1631 } 1632 else { /* unicast address */ 1633 if (ni6->ni_flags & NI_NODEADDR_FLAG_ANYCAST) 1634 continue; 1635 else 1636 docopy = 1; 1637 } 1638 1639 /* What do we have to do about ::1? */ 1640 switch(in6_addrscope(&ifa6->ia_addr.sin6_addr)) { 1641 case IPV6_ADDR_SCOPE_LINKLOCAL: 1642 if (ni6->ni_flags & NI_NODEADDR_FLAG_LINKLOCAL) 1643 docopy = 1; 1644 break; 1645 case IPV6_ADDR_SCOPE_SITELOCAL: 1646 if (ni6->ni_flags & NI_NODEADDR_FLAG_SITELOCAL) 1647 docopy = 1; 1648 break; 1649 case IPV6_ADDR_SCOPE_GLOBAL: 1650 if (ni6->ni_flags & NI_NODEADDR_FLAG_GLOBAL) 1651 docopy = 1; 1652 break; 1653 default: 1654 continue; 1655 } 1656 1657 if (docopy) { 1658 if (resid < sizeof(struct in6_addr)) { 1659 /* 1660 * We give up much more copy. 1661 * Set the truncate flag and return. 1662 */ 1663 nni6->ni_flags |= 1664 NI_NODEADDR_FLAG_TRUNCATE; 1665 return(copied); 1666 } 1667 bcopy(&ifa6->ia_addr.sin6_addr, cp, 1668 sizeof(struct in6_addr)); 1669 /* XXX: KAME link-local hack; remove ifindex */ 1670 if (IN6_IS_ADDR_LINKLOCAL(&ifa6->ia_addr.sin6_addr)) 1671 ((struct in6_addr *)cp)->s6_addr16[1] = 0; 1672 cp += sizeof(struct in6_addr); 1673 resid -= sizeof(struct in6_addr); 1674 copied += sizeof(struct in6_addr); 1675 } 1676 } 1677 if (ifp0) /* we need search only on the specified IF */ 1678 break; 1679 } 1680 1681 return(copied); 1682} 1683 1684/* 1685 * XXX almost dup'ed code with rip6_input. 1686 */ 1687static int 1688icmp6_rip6_input(mp, off) 1689 struct mbuf **mp; 1690 int off; 1691{ 1692 struct mbuf *m = *mp; 1693 register struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1694 register struct in6pcb *in6p; 1695 struct in6pcb *last = NULL; 1696 struct sockaddr_in6 rip6src; 1697 struct icmp6_hdr *icmp6; 1698 struct mbuf *opts = NULL; 1699 1700#ifndef PULLDOWN_TEST 1701 /* this is assumed to be safe. */ 1702 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off); 1703#else 1704 IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6)); 1705 if (icmp6 == NULL) { 1706 /* m is already reclaimed */ 1707 return IPPROTO_DONE; 1708 } 1709#endif 1710 1711 bzero(&rip6src, sizeof(rip6src)); 1712 rip6src.sin6_len = sizeof(struct sockaddr_in6); 1713 rip6src.sin6_family = AF_INET6; 1714 /* KAME hack: recover scopeid */ 1715 (void)in6_recoverscope(&rip6src, &ip6->ip6_src, m->m_pkthdr.rcvif); 1716 1717 LIST_FOREACH(in6p, &ripcb, inp_list) 1718 { 1719 if ((in6p->inp_vflag & INP_IPV6) == NULL) 1720 continue; 1721 if (in6p->in6p_ip6_nxt != IPPROTO_ICMPV6) 1722 continue; 1723 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr) && 1724 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr, &ip6->ip6_dst)) 1725 continue; 1726 if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr) && 1727 !IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr, &ip6->ip6_src)) 1728 continue; 1729 if (in6p->in6p_icmp6filt 1730 && ICMP6_FILTER_WILLBLOCK(icmp6->icmp6_type, 1731 in6p->in6p_icmp6filt)) 1732 continue; 1733 if (last) { 1734 struct mbuf *n; 1735 if ((n = m_copy(m, 0, (int)M_COPYALL)) != NULL) { 1736 if (last->in6p_flags & IN6P_CONTROLOPTS) 1737 ip6_savecontrol(last, &opts, ip6, n); 1738 /* strip intermediate headers */ 1739 m_adj(n, off); 1740 if (sbappendaddr(&last->in6p_socket->so_rcv, 1741 (struct sockaddr *)&rip6src, 1742 n, opts) == 0) { 1743 /* should notify about lost packet */ 1744 m_freem(n); 1745 if (opts) 1746 m_freem(opts); 1747 } else 1748 sorwakeup(last->in6p_socket); 1749 opts = NULL; 1750 } 1751 } 1752 last = in6p; 1753 } 1754 if (last) { 1755 if (last->in6p_flags & IN6P_CONTROLOPTS) 1756 ip6_savecontrol(last, &opts, ip6, m); 1757 /* strip intermediate headers */ 1758 m_adj(m, off); 1759 if (sbappendaddr(&last->in6p_socket->so_rcv, 1760 (struct sockaddr *)&rip6src, m, opts) == 0) { 1761 m_freem(m); 1762 if (opts) 1763 m_freem(opts); 1764 } else 1765 sorwakeup(last->in6p_socket); 1766 } else { 1767 m_freem(m); 1768 ip6stat.ip6s_delivered--; 1769 } 1770 return IPPROTO_DONE; 1771} 1772 1773/* 1774 * Reflect the ip6 packet back to the source. 1775 * OFF points to the icmp6 header, counted from the top of the mbuf. 1776 */ 1777void 1778icmp6_reflect(m, off) 1779 struct mbuf *m; 1780 size_t off; 1781{ 1782 struct ip6_hdr *ip6; 1783 struct icmp6_hdr *icmp6; 1784 struct in6_ifaddr *ia; 1785 struct in6_addr t, *src = 0; 1786 int plen; 1787 int type, code; 1788 struct ifnet *outif = NULL; 1789#ifdef COMPAT_RFC1885 1790 int mtu = IPV6_MMTU; 1791 struct sockaddr_in6 *sin6 = &icmp6_reflect_rt.ro_dst; 1792#endif 1793 1794 /* too short to reflect */ 1795 if (off < sizeof(struct ip6_hdr)) { 1796 printf("sanity fail: off=%lx, sizeof(ip6)=%lx in %s:%d\n", 1797 (u_long)off, (u_long)sizeof(struct ip6_hdr), 1798 __FILE__, __LINE__); 1799 goto bad; 1800 } 1801 1802 /* 1803 * If there are extra headers between IPv6 and ICMPv6, strip 1804 * off that header first. 1805 */ 1806#ifdef DIAGNOSTIC 1807 if (sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) > MHLEN) 1808 panic("assumption failed in icmp6_reflect"); 1809#endif 1810 if (off > sizeof(struct ip6_hdr)) { 1811 size_t l; 1812 struct ip6_hdr nip6; 1813 1814 l = off - sizeof(struct ip6_hdr); 1815 m_copydata(m, 0, sizeof(nip6), (caddr_t)&nip6); 1816 m_adj(m, l); 1817 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 1818 if (m->m_len < l) { 1819 if ((m = m_pullup(m, l)) == NULL) 1820 return; 1821 } 1822 bcopy((caddr_t)&nip6, mtod(m, caddr_t), sizeof(nip6)); 1823 } else /* off == sizeof(struct ip6_hdr) */ { 1824 size_t l; 1825 l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr); 1826 if (m->m_len < l) { 1827 if ((m = m_pullup(m, l)) == NULL) 1828 return; 1829 } 1830 } 1831 plen = m->m_pkthdr.len - sizeof(struct ip6_hdr); 1832 ip6 = mtod(m, struct ip6_hdr *); 1833 ip6->ip6_nxt = IPPROTO_ICMPV6; 1834 icmp6 = (struct icmp6_hdr *)(ip6 + 1); 1835 type = icmp6->icmp6_type; /* keep type for statistics */ 1836 code = icmp6->icmp6_code; /* ditto. */ 1837 1838 t = ip6->ip6_dst; 1839 /* 1840 * ip6_input() drops a packet if its src is multicast. 1841 * So, the src is never multicast. 1842 */ 1843 ip6->ip6_dst = ip6->ip6_src; 1844 1845 /* XXX hack for link-local addresses */ 1846 if (IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_dst)) 1847 ip6->ip6_dst.s6_addr16[1] = 1848 htons(m->m_pkthdr.rcvif->if_index); 1849 if (IN6_IS_ADDR_LINKLOCAL(&t)) 1850 t.s6_addr16[1] = htons(m->m_pkthdr.rcvif->if_index); 1851 1852#ifdef COMPAT_RFC1885 1853 /* 1854 * xxx guess MTU 1855 * RFC 1885 requires that echo reply should be truncated if it 1856 * does not fit in with (return) path MTU, but the description was 1857 * removed in the new spec. 1858 */ 1859 if (icmp6_reflect_rt.ro_rt == 0 || 1860 ! (IN6_ARE_ADDR_EQUAL(&sin6->sin6_addr, &ip6->ip6_dst))) { 1861 if (icmp6_reflect_rt.ro_rt) { 1862 RTFREE(icmp6_reflect_rt.ro_rt); 1863 icmp6_reflect_rt.ro_rt = 0; 1864 } 1865 bzero(sin6, sizeof(*sin6)); 1866 sin6->sin6_family = PF_INET6; 1867 sin6->sin6_len = sizeof(struct sockaddr_in6); 1868 sin6->sin6_addr = ip6->ip6_dst; 1869 1870 rtalloc_ign((struct route *)&icmp6_reflect_rt.ro_rt, 1871 RTF_PRCLONING); 1872 } 1873 1874 if (icmp6_reflect_rt.ro_rt == 0) 1875 goto bad; 1876 1877 if ((icmp6_reflect_rt.ro_rt->rt_flags & RTF_HOST) 1878 && mtu < icmp6_reflect_rt.ro_rt->rt_ifp->if_mtu) 1879 mtu = icmp6_reflect_rt.ro_rt->rt_rmx.rmx_mtu; 1880 1881 if (mtu < m->m_pkthdr.len) { 1882 plen -= (m->m_pkthdr.len - mtu); 1883 m_adj(m, mtu - m->m_pkthdr.len); 1884 } 1885#endif 1886 /* 1887 * If the incoming packet was addressed directly to us(i.e. unicast), 1888 * use dst as the src for the reply. 1889 * The IN6_IFF_NOTREADY case would be VERY rare, but is possible 1890 * (for example) when we encounter an error while forwarding procedure 1891 * destined to a duplicated address of ours. 1892 */ 1893 for (ia = in6_ifaddr; ia; ia = ia->ia_next) 1894 if (IN6_ARE_ADDR_EQUAL(&t, &ia->ia_addr.sin6_addr) && 1895 (ia->ia6_flags & (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY)) == 0) { 1896 src = &t; 1897 break; 1898 } 1899 if (ia == NULL && IN6_IS_ADDR_LINKLOCAL(&t) && (m->m_flags & M_LOOP)) { 1900 /* 1901 * This is the case if the dst is our link-local address 1902 * and the sender is also ourseleves. 1903 */ 1904 src = &t; 1905 } 1906 1907 if (src == 0) 1908 /* 1909 * This case matches to multicasts, our anycast, or unicasts 1910 * that we do not own. Select a source address which has the 1911 * same scope. 1912 * XXX: for (non link-local) multicast addresses, this might 1913 * not be a good choice. 1914 */ 1915 if ((ia = in6_ifawithscope(m->m_pkthdr.rcvif, &t)) != 0) 1916 src = &IA6_SIN6(ia)->sin6_addr; 1917 1918 if (src == 0) 1919 goto bad; 1920 1921 ip6->ip6_src = *src; 1922 1923 ip6->ip6_flow = 0; 1924 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 1925 ip6->ip6_vfc |= IPV6_VERSION; 1926 ip6->ip6_nxt = IPPROTO_ICMPV6; 1927 if (m->m_pkthdr.rcvif) { 1928 /* XXX: This may not be the outgoing interface */ 1929 ip6->ip6_hlim = nd_ifinfo[m->m_pkthdr.rcvif->if_index].chlim; 1930 } 1931 1932 icmp6->icmp6_cksum = 0; 1933 icmp6->icmp6_cksum = in6_cksum(m, IPPROTO_ICMPV6, 1934 sizeof(struct ip6_hdr), plen); 1935 1936 /* 1937 * xxx option handling 1938 */ 1939 1940 m->m_flags &= ~(M_BCAST|M_MCAST); 1941#ifdef IPSEC 1942 /* Don't lookup socket */ 1943 ipsec_setsocket(m, NULL); 1944#endif /*IPSEC*/ 1945 1946#ifdef COMPAT_RFC1885 1947 ip6_output(m, NULL, &icmp6_reflect_rt, 0, NULL, &outif); 1948#else 1949 ip6_output(m, NULL, NULL, 0, NULL, &outif); 1950#endif 1951 if (outif) 1952 icmp6_ifoutstat_inc(outif, type, code); 1953 1954 return; 1955 1956 bad: 1957 m_freem(m); 1958 return; 1959} 1960 1961void 1962icmp6_fasttimo() 1963{ 1964 1965 mld6_fasttimeo(); 1966 1967 /* reset ICMPv6 pps limit */ 1968 icmp6errpps_count = 0; 1969} 1970 1971static const char * 1972icmp6_redirect_diag(src6, dst6, tgt6) 1973 struct in6_addr *src6; 1974 struct in6_addr *dst6; 1975 struct in6_addr *tgt6; 1976{ 1977 static char buf[1024]; 1978 snprintf(buf, sizeof(buf), "(src=%s dst=%s tgt=%s)", 1979 ip6_sprintf(src6), ip6_sprintf(dst6), ip6_sprintf(tgt6)); 1980 return buf; 1981} 1982 1983void 1984icmp6_redirect_input(m, off) 1985 register struct mbuf *m; 1986 int off; 1987{ 1988 struct ifnet *ifp = m->m_pkthdr.rcvif; 1989 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); 1990 struct nd_redirect *nd_rd; 1991 int icmp6len = ntohs(ip6->ip6_plen); 1992 char *lladdr = NULL; 1993 int lladdrlen = 0; 1994 u_char *redirhdr = NULL; 1995 int redirhdrlen = 0; 1996 struct rtentry *rt = NULL; 1997 int is_router; 1998 int is_onlink; 1999 struct in6_addr src6 = ip6->ip6_src; 2000 struct in6_addr redtgt6; 2001 struct in6_addr reddst6; 2002 union nd_opts ndopts; 2003 2004 if (!m || !ifp) 2005 return; 2006 2007 /* XXX if we are router, we don't update route by icmp6 redirect */ 2008 if (ip6_forwarding) 2009 goto freeit; 2010 if (!icmp6_rediraccept) 2011 goto freeit; 2012 2013#ifndef PULLDOWN_TEST 2014 IP6_EXTHDR_CHECK(m, off, icmp6len,); 2015 nd_rd = (struct nd_redirect *)((caddr_t)ip6 + off); 2016#else 2017 IP6_EXTHDR_GET(nd_rd, struct nd_redirect *, m, off, icmp6len); 2018 if (nd_rd == NULL) { 2019 icmp6stat.icp6s_tooshort++; 2020 return; 2021 } 2022#endif 2023 redtgt6 = nd_rd->nd_rd_target; 2024 reddst6 = nd_rd->nd_rd_dst; 2025 2026 if (IN6_IS_ADDR_LINKLOCAL(&redtgt6)) 2027 redtgt6.s6_addr16[1] = htons(ifp->if_index); 2028 if (IN6_IS_ADDR_LINKLOCAL(&reddst6)) 2029 reddst6.s6_addr16[1] = htons(ifp->if_index); 2030 2031 /* validation */ 2032 if (!IN6_IS_ADDR_LINKLOCAL(&src6)) { 2033 log(LOG_ERR, 2034 "ICMP6 redirect sent from %s rejected; " 2035 "must be from linklocal\n", ip6_sprintf(&src6)); 2036 goto freeit; 2037 } 2038 if (ip6->ip6_hlim != 255) { 2039 log(LOG_ERR, 2040 "ICMP6 redirect sent from %s rejected; " 2041 "hlim=%d (must be 255)\n", 2042 ip6_sprintf(&src6), ip6->ip6_hlim); 2043 goto freeit; 2044 } 2045 { 2046 /* ip6->ip6_src must be equal to gw for icmp6->icmp6_reddst */ 2047 struct sockaddr_in6 sin6; 2048 struct in6_addr *gw6; 2049 2050 bzero(&sin6, sizeof(sin6)); 2051 sin6.sin6_family = AF_INET6; 2052 sin6.sin6_len = sizeof(struct sockaddr_in6); 2053 bcopy(&reddst6, &sin6.sin6_addr, sizeof(reddst6)); 2054 rt = rtalloc1((struct sockaddr *)&sin6, 0, 0UL); 2055 if (rt) { 2056 gw6 = &(((struct sockaddr_in6 *)rt->rt_gateway)->sin6_addr); 2057 if (bcmp(&src6, gw6, sizeof(struct in6_addr)) != 0) { 2058 log(LOG_ERR, 2059 "ICMP6 redirect rejected; " 2060 "not equal to gw-for-src=%s (must be same): " 2061 "%s\n", 2062 ip6_sprintf(gw6), 2063 icmp6_redirect_diag(&src6, &reddst6, &redtgt6)); 2064 RTFREE(rt); 2065 goto freeit; 2066 } 2067 } else { 2068 log(LOG_ERR, 2069 "ICMP6 redirect rejected; " 2070 "no route found for redirect dst: %s\n", 2071 icmp6_redirect_diag(&src6, &reddst6, &redtgt6)); 2072 goto freeit; 2073 } 2074 RTFREE(rt); 2075 rt = NULL; 2076 } 2077 if (IN6_IS_ADDR_MULTICAST(&reddst6)) { 2078 log(LOG_ERR, 2079 "ICMP6 redirect rejected; " 2080 "redirect dst must be unicast: %s\n", 2081 icmp6_redirect_diag(&src6, &reddst6, &redtgt6)); 2082 goto freeit; 2083 } 2084 2085 is_router = is_onlink = 0; 2086 if (IN6_IS_ADDR_LINKLOCAL(&redtgt6)) 2087 is_router = 1; /* router case */ 2088 if (bcmp(&redtgt6, &reddst6, sizeof(redtgt6)) == 0) 2089 is_onlink = 1; /* on-link destination case */ 2090 if (!is_router && !is_onlink) { 2091 log(LOG_ERR, 2092 "ICMP6 redirect rejected; " 2093 "neither router case nor onlink case: %s\n", 2094 icmp6_redirect_diag(&src6, &reddst6, &redtgt6)); 2095 goto freeit; 2096 } 2097 /* validation passed */ 2098 2099 icmp6len -= sizeof(*nd_rd); 2100 nd6_option_init(nd_rd + 1, icmp6len, &ndopts); 2101 if (nd6_options(&ndopts) < 0) { 2102 log(LOG_INFO, "icmp6_redirect_input: " 2103 "invalid ND option, rejected: %s\n", 2104 icmp6_redirect_diag(&src6, &reddst6, &redtgt6)); 2105 goto freeit; 2106 } 2107 2108 if (ndopts.nd_opts_tgt_lladdr) { 2109 lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1); 2110 lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3; 2111 } 2112 2113 if (ndopts.nd_opts_rh) { 2114 redirhdrlen = ndopts.nd_opts_rh->nd_opt_rh_len; 2115 redirhdr = (u_char *)(ndopts.nd_opts_rh + 1); /* xxx */ 2116 } 2117 2118 if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) { 2119 log(LOG_INFO, 2120 "icmp6_redirect_input: lladdrlen mismatch for %s " 2121 "(if %d, icmp6 packet %d): %s\n", 2122 ip6_sprintf(&redtgt6), ifp->if_addrlen, lladdrlen - 2, 2123 icmp6_redirect_diag(&src6, &reddst6, &redtgt6)); 2124 } 2125 2126 /* RFC 2461 8.3 */ 2127 nd6_cache_lladdr(ifp, &redtgt6, lladdr, lladdrlen, ND_REDIRECT, 2128 is_onlink ? ND_REDIRECT_ONLINK : ND_REDIRECT_ROUTER); 2129 2130 if (!is_onlink) { /* better router case. perform rtredirect. */ 2131 /* perform rtredirect */ 2132 struct sockaddr_in6 sdst; 2133 struct sockaddr_in6 sgw; 2134 struct sockaddr_in6 ssrc; 2135 2136 bzero(&sdst, sizeof(sdst)); 2137 bzero(&sgw, sizeof(sgw)); 2138 bzero(&ssrc, sizeof(ssrc)); 2139 sdst.sin6_family = sgw.sin6_family = ssrc.sin6_family = AF_INET6; 2140 sdst.sin6_len = sgw.sin6_len = ssrc.sin6_len = 2141 sizeof(struct sockaddr_in6); 2142 bcopy(&redtgt6, &sgw.sin6_addr, sizeof(struct in6_addr)); 2143 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2144 bcopy(&src6, &ssrc.sin6_addr, sizeof(struct in6_addr)); 2145 rtredirect((struct sockaddr *)&sdst, (struct sockaddr *)&sgw, 2146 (struct sockaddr *)NULL, RTF_GATEWAY | RTF_HOST, 2147 (struct sockaddr *)&ssrc, 2148 (struct rtentry **)NULL); 2149 } 2150 /* finally update cached route in each socket via pfctlinput */ 2151 { 2152 struct sockaddr_in6 sdst; 2153 2154 bzero(&sdst, sizeof(sdst)); 2155 sdst.sin6_family = AF_INET6; 2156 sdst.sin6_len = sizeof(struct sockaddr_in6); 2157 bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr)); 2158 pfctlinput(PRC_REDIRECT_HOST, (struct sockaddr *)&sdst); 2159#ifdef IPSEC 2160 key_sa_routechange((struct sockaddr *)&sdst); 2161#endif 2162 } 2163 2164 freeit: 2165 m_freem(m); 2166} 2167 2168void 2169icmp6_redirect_output(m0, rt) 2170 struct mbuf *m0; 2171 struct rtentry *rt; 2172{ 2173 struct ifnet *ifp; /* my outgoing interface */ 2174 struct in6_addr *ifp_ll6; 2175 struct in6_addr *router_ll6; 2176 struct ip6_hdr *sip6; /* m0 as struct ip6_hdr */ 2177 struct mbuf *m = NULL; /* newly allocated one */ 2178 struct ip6_hdr *ip6; /* m as struct ip6_hdr */ 2179 struct nd_redirect *nd_rd; 2180 size_t maxlen; 2181 u_char *p; 2182 struct ifnet *outif = NULL; 2183 struct sockaddr_in6 src_sa; 2184 2185 icmp6_errcount(&icmp6stat.icp6s_outerrhist, ND_REDIRECT, 0); 2186 2187 /* if we are not router, we don't send icmp6 redirect */ 2188 if (!ip6_forwarding || ip6_accept_rtadv) 2189 goto fail; 2190 2191 /* sanity check */ 2192 if (!m0 || !rt || !(rt->rt_flags & RTF_UP) || !(ifp = rt->rt_ifp)) 2193 goto fail; 2194 2195 /* 2196 * Address check: 2197 * the source address must identify a neighbor, and 2198 * the destination address must not be a multicast address 2199 * [RFC 2461, sec 8.2] 2200 */ 2201 sip6 = mtod(m0, struct ip6_hdr *); 2202 bzero(&src_sa, sizeof(src_sa)); 2203 src_sa.sin6_family = AF_INET6; 2204 src_sa.sin6_len = sizeof(src_sa); 2205 src_sa.sin6_addr = sip6->ip6_src; 2206 /* we don't currently use sin6_scope_id, but eventually use it */ 2207 src_sa.sin6_scope_id = in6_addr2scopeid(ifp, &sip6->ip6_src); 2208 if (nd6_is_addr_neighbor(&src_sa, ifp) == 0) 2209 goto fail; 2210 if (IN6_IS_ADDR_MULTICAST(&sip6->ip6_dst)) 2211 goto fail; /* what should we do here? */ 2212 2213 /* rate limit */ 2214 if (icmp6_ratelimit(&sip6->ip6_src, ND_REDIRECT, 0)) 2215 goto fail; 2216 2217 /* 2218 * Since we are going to append up to 1280 bytes (= IPV6_MMTU), 2219 * we almost always ask for an mbuf cluster for simplicity. 2220 * (MHLEN < IPV6_MMTU is almost always true) 2221 */ 2222#if IPV6_MMTU >= MCLBYTES 2223# error assumption failed about IPV6_MMTU and MCLBYTES 2224#endif 2225 MGETHDR(m, M_DONTWAIT, MT_HEADER); 2226 if (m && IPV6_MMTU >= MHLEN) 2227 MCLGET(m, M_DONTWAIT); 2228 if (!m) 2229 goto fail; 2230 maxlen = (m->m_flags & M_EXT) ? MCLBYTES : MHLEN; 2231 maxlen = min(IPV6_MMTU, maxlen); 2232 /* just for safety */ 2233 if (maxlen < sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr) + 2234 ((sizeof(struct nd_opt_hdr) + ifp->if_addrlen + 7) & ~7)) { 2235 goto fail; 2236 } 2237 2238 { 2239 /* get ip6 linklocal address for ifp(my outgoing interface). */ 2240 struct in6_ifaddr *ia; 2241 if ((ia = in6ifa_ifpforlinklocal(ifp, 2242 IN6_IFF_NOTREADY| 2243 IN6_IFF_ANYCAST)) == NULL) 2244 goto fail; 2245 ifp_ll6 = &ia->ia_addr.sin6_addr; 2246 } 2247 2248 /* get ip6 linklocal address for the router. */ 2249 if (rt->rt_gateway && (rt->rt_flags & RTF_GATEWAY)) { 2250 struct sockaddr_in6 *sin6; 2251 sin6 = (struct sockaddr_in6 *)rt->rt_gateway; 2252 router_ll6 = &sin6->sin6_addr; 2253 if (!IN6_IS_ADDR_LINKLOCAL(router_ll6)) 2254 router_ll6 = (struct in6_addr *)NULL; 2255 } else 2256 router_ll6 = (struct in6_addr *)NULL; 2257 2258 /* ip6 */ 2259 ip6 = mtod(m, struct ip6_hdr *); 2260 ip6->ip6_flow = 0; 2261 ip6->ip6_vfc &= ~IPV6_VERSION_MASK; 2262 ip6->ip6_vfc |= IPV6_VERSION; 2263 /* ip6->ip6_plen will be set later */ 2264 ip6->ip6_nxt = IPPROTO_ICMPV6; 2265 ip6->ip6_hlim = 255; 2266 /* ip6->ip6_src must be linklocal addr for my outgoing if. */ 2267 bcopy(ifp_ll6, &ip6->ip6_src, sizeof(struct in6_addr)); 2268 bcopy(&sip6->ip6_src, &ip6->ip6_dst, sizeof(struct in6_addr)); 2269 2270 /* ND Redirect */ 2271 nd_rd = (struct nd_redirect *)(ip6 + 1); 2272 nd_rd->nd_rd_type = ND_REDIRECT; 2273 nd_rd->nd_rd_code = 0; 2274 nd_rd->nd_rd_reserved = 0; 2275 if (rt->rt_flags & RTF_GATEWAY) { 2276 /* 2277 * nd_rd->nd_rd_target must be a link-local address in 2278 * better router cases. 2279 */ 2280 if (!router_ll6) 2281 goto fail; 2282 bcopy(router_ll6, &nd_rd->nd_rd_target, 2283 sizeof(nd_rd->nd_rd_target)); 2284 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2285 sizeof(nd_rd->nd_rd_dst)); 2286 } else { 2287 /* make sure redtgt == reddst */ 2288 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_target, 2289 sizeof(nd_rd->nd_rd_target)); 2290 bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst, 2291 sizeof(nd_rd->nd_rd_dst)); 2292 } 2293 2294 p = (u_char *)(nd_rd + 1); 2295 2296 if (!router_ll6) 2297 goto nolladdropt; 2298 2299 { 2300 /* target lladdr option */ 2301 struct rtentry *rt_router = NULL; 2302 int len; 2303 struct sockaddr_dl *sdl; 2304 struct nd_opt_hdr *nd_opt; 2305 char *lladdr; 2306 2307 rt_router = nd6_lookup(router_ll6, 0, ifp); 2308 if (!rt_router) 2309 goto nolladdropt; 2310 len = sizeof(*nd_opt) + ifp->if_addrlen; 2311 len = (len + 7) & ~7; /*round by 8*/ 2312 /* safety check */ 2313 if (len + (p - (u_char *)ip6) > maxlen) 2314 goto nolladdropt; 2315 if (!(rt_router->rt_flags & RTF_GATEWAY) && 2316 (rt_router->rt_flags & RTF_LLINFO) && 2317 (rt_router->rt_gateway->sa_family == AF_LINK) && 2318 (sdl = (struct sockaddr_dl *)rt_router->rt_gateway) && 2319 sdl->sdl_alen) { 2320 nd_opt = (struct nd_opt_hdr *)p; 2321 nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR; 2322 nd_opt->nd_opt_len = len >> 3; 2323 lladdr = (char *)(nd_opt + 1); 2324 bcopy(LLADDR(sdl), lladdr, ifp->if_addrlen); 2325 p += len; 2326 } 2327 } 2328nolladdropt:; 2329 2330 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2331 2332 /* just to be safe */ 2333#ifdef M_DECRYPTED /*not openbsd*/ 2334 if (m0->m_flags & M_DECRYPTED) 2335 goto noredhdropt; 2336#endif 2337 if (p - (u_char *)ip6 > maxlen) 2338 goto noredhdropt; 2339 2340 { 2341 /* redirected header option */ 2342 int len; 2343 struct nd_opt_rd_hdr *nd_opt_rh; 2344 2345 /* 2346 * compute the maximum size for icmp6 redirect header option. 2347 * XXX room for auth header? 2348 */ 2349 len = maxlen - (p - (u_char *)ip6); 2350 len &= ~7; 2351 2352 /* This is just for simplicity. */ 2353 if (m0->m_pkthdr.len != m0->m_len) { 2354 if (m0->m_next) { 2355 m_freem(m0->m_next); 2356 m0->m_next = NULL; 2357 } 2358 m0->m_pkthdr.len = m0->m_len; 2359 } 2360 2361 /* 2362 * Redirected header option spec (RFC2461 4.6.3) talks nothing 2363 * about padding/truncate rule for the original IP packet. 2364 * From the discussion on IPv6imp in Feb 1999, the consensus was: 2365 * - "attach as much as possible" is the goal 2366 * - pad if not aligned (original size can be guessed by original 2367 * ip6 header) 2368 * Following code adds the padding if it is simple enough, 2369 * and truncates if not. 2370 */ 2371 if (m0->m_next || m0->m_pkthdr.len != m0->m_len) 2372 panic("assumption failed in %s:%d\n", __FILE__, __LINE__); 2373 2374 if (len - sizeof(*nd_opt_rh) < m0->m_pkthdr.len) { 2375 /* not enough room, truncate */ 2376 m0->m_pkthdr.len = m0->m_len = len - sizeof(*nd_opt_rh); 2377 } else { 2378 /* enough room, pad or truncate */ 2379 size_t extra; 2380 2381 extra = m0->m_pkthdr.len % 8; 2382 if (extra) { 2383 /* pad if easy enough, truncate if not */ 2384 if (8 - extra <= M_TRAILINGSPACE(m0)) { 2385 /* pad */ 2386 m0->m_len += (8 - extra); 2387 m0->m_pkthdr.len += (8 - extra); 2388 } else { 2389 /* truncate */ 2390 m0->m_pkthdr.len -= extra; 2391 m0->m_len -= extra; 2392 } 2393 } 2394 len = m0->m_pkthdr.len + sizeof(*nd_opt_rh); 2395 m0->m_pkthdr.len = m0->m_len = len - sizeof(*nd_opt_rh); 2396 } 2397 2398 nd_opt_rh = (struct nd_opt_rd_hdr *)p; 2399 bzero(nd_opt_rh, sizeof(*nd_opt_rh)); 2400 nd_opt_rh->nd_opt_rh_type = ND_OPT_REDIRECTED_HEADER; 2401 nd_opt_rh->nd_opt_rh_len = len >> 3; 2402 p += sizeof(*nd_opt_rh); 2403 m->m_pkthdr.len = m->m_len = p - (u_char *)ip6; 2404 2405 /* connect m0 to m */ 2406 m->m_next = m0; 2407 m->m_pkthdr.len = m->m_len + m0->m_len; 2408 } 2409noredhdropt:; 2410 2411 if (IN6_IS_ADDR_LINKLOCAL(&sip6->ip6_src)) 2412 sip6->ip6_src.s6_addr16[1] = 0; 2413 if (IN6_IS_ADDR_LINKLOCAL(&sip6->ip6_dst)) 2414 sip6->ip6_dst.s6_addr16[1] = 0; 2415#if 0 2416 if (IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_src)) 2417 ip6->ip6_src.s6_addr16[1] = 0; 2418 if (IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_dst)) 2419 ip6->ip6_dst.s6_addr16[1] = 0; 2420#endif 2421 if (IN6_IS_ADDR_LINKLOCAL(&nd_rd->nd_rd_target)) 2422 nd_rd->nd_rd_target.s6_addr16[1] = 0; 2423 if (IN6_IS_ADDR_LINKLOCAL(&nd_rd->nd_rd_dst)) 2424 nd_rd->nd_rd_dst.s6_addr16[1] = 0; 2425 2426 ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr)); 2427 2428 nd_rd->nd_rd_cksum = 0; 2429 nd_rd->nd_rd_cksum 2430 = in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), ntohs(ip6->ip6_plen)); 2431 2432 /* send the packet to outside... */ 2433#ifdef IPSEC 2434 /* Don't lookup socket */ 2435 ipsec_setsocket(m, NULL); 2436#endif /*IPSEC*/ 2437 ip6_output(m, NULL, NULL, 0, NULL, &outif); 2438 if (outif) { 2439 icmp6_ifstat_inc(outif, ifs6_out_msg); 2440 icmp6_ifstat_inc(outif, ifs6_out_redirect); 2441 } 2442 icmp6stat.icp6s_outhist[ND_REDIRECT]++; 2443 2444 return; 2445 2446fail: 2447 if (m) 2448 m_freem(m); 2449 if (m0) 2450 m_freem(m0); 2451} 2452 2453/* 2454 * ICMPv6 socket option processing. 2455 * 2456 * NOTE: for OSes that use NRL inpcb (bsdi4/openbsd), do not forget to modify 2457 * sys/netinet6/raw_ipv6.c:rip6_ctloutput(). 2458 */ 2459int 2460icmp6_ctloutput(so, sopt) 2461 struct socket *so; 2462 struct sockopt *sopt; 2463{ 2464 int error = 0; 2465 int optlen; 2466 register struct inpcb *inp = sotoinpcb(so); 2467 int level, op, optname; 2468 2469 if (sopt) { 2470 level = sopt->sopt_level; 2471 op = sopt->sopt_dir; 2472 optname = sopt->sopt_name; 2473 optlen = sopt->sopt_valsize; 2474 } else 2475 level = op = optname = optlen = 0; 2476 if (level != IPPROTO_ICMPV6) { 2477 return EINVAL; 2478 } 2479 2480 switch(op) { 2481 case PRCO_SETOPT: 2482 switch (optname) { 2483 case ICMP6_FILTER: 2484 { 2485 struct icmp6_filter *p; 2486 2487 if (optlen != sizeof(*p)) { 2488 error = EMSGSIZE; 2489 break; 2490 } 2491 if (inp->in6p_icmp6filt == NULL) { 2492 error = EINVAL; 2493 break; 2494 } 2495 error = sooptcopyin(sopt, inp->in6p_icmp6filt, optlen, 2496 optlen); 2497 break; 2498 } 2499 2500 default: 2501 error = ENOPROTOOPT; 2502 break; 2503 } 2504 break; 2505 2506 case PRCO_GETOPT: 2507 switch (optname) { 2508 case ICMP6_FILTER: 2509 { 2510 if (inp->in6p_icmp6filt == NULL) { 2511 error = EINVAL; 2512 break; 2513 } 2514 error = sooptcopyout(sopt, inp->in6p_icmp6filt, 2515 sizeof(struct icmp6_filter)); 2516 break; 2517 } 2518 2519 default: 2520 error = ENOPROTOOPT; 2521 break; 2522 } 2523 break; 2524 } 2525 2526 return(error); 2527} 2528 2529#ifndef HAVE_RATECHECK 2530/* 2531 * ratecheck() returns true if it is okay to send. We return 2532 * true if it is not okay to send. 2533 */ 2534static int 2535ratecheck(last, limit) 2536 struct timeval *last; 2537 struct timeval *limit; 2538{ 2539 struct timeval tp; 2540 struct timeval nextsend; 2541 2542 microtime(&tp); 2543 tp.tv_sec = time_second; 2544 2545 /* rate limit */ 2546 if (last->tv_sec != 0 || last->tv_usec != 0) { 2547 nextsend.tv_sec = last->tv_sec + limit->tv_sec; 2548 nextsend.tv_usec = last->tv_usec + limit->tv_usec; 2549 nextsend.tv_sec += (nextsend.tv_usec / 1000000); 2550 nextsend.tv_usec %= 1000000; 2551 2552 if (nextsend.tv_sec == tp.tv_sec && nextsend.tv_usec <= tp.tv_usec) 2553 ; 2554 else if (nextsend.tv_sec <= tp.tv_sec) 2555 ; 2556 else { 2557 /* The packet is subject to rate limit */ 2558 return 0; 2559 } 2560 } 2561 2562 *last = tp; 2563 return 1; 2564} 2565#endif 2566 2567/* 2568 * Perform rate limit check. 2569 * Returns 0 if it is okay to send the icmp6 packet. 2570 * Returns 1 if the router SHOULD NOT send this icmp6 packet due to rate 2571 * limitation. 2572 * 2573 * There are two limitations defined: 2574 * - pps limit: ICMPv6 error packet cannot exceed defined packet-per-second. 2575 * we measure it every 0.2 second, since fasttimo works every 0.2 second. 2576 * - rate limit: ICMPv6 error packet cannot appear more than once per 2577 * defined interval. 2578 * In any case, if we perform rate limitation, we'll see jitter in the ICMPv6 2579 * error packets. 2580 * 2581 * XXX per-destination/type check necessary? 2582 */ 2583static int 2584icmp6_ratelimit(dst, type, code) 2585 const struct in6_addr *dst; /* not used at this moment */ 2586 const int type; /* not used at this moment */ 2587 const int code; /* not used at this moment */ 2588{ 2589 int ret; 2590 2591 ret = 0; /*okay to send*/ 2592 2593 /* PPS limit */ 2594 icmp6errpps_count++; 2595 if (icmp6errppslim && icmp6errpps_count > icmp6errppslim / 5) { 2596 /* The packet is subject to pps limit */ 2597 ret++; 2598 } 2599 2600 if (!ratecheck(&icmp6errratelim_last, &icmp6errratelim)) { 2601 /* The packet is subject to rate limit */ 2602 ret++; 2603 } 2604 2605 return ret; 2606} 2607