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icmp6.c revision 1.22
      1 /*	$NetBSD: icmp6.c,v 1.22 2000/02/17 10:59:38 darrenr Exp $	*/
      2 
      3 /*
      4  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
      5  * All rights reserved.
      6  *
      7  * Redistribution and use in source and binary forms, with or without
      8  * modification, are permitted provided that the following conditions
      9  * are met:
     10  * 1. Redistributions of source code must retain the above copyright
     11  *    notice, this list of conditions and the following disclaimer.
     12  * 2. Redistributions in binary form must reproduce the above copyright
     13  *    notice, this list of conditions and the following disclaimer in the
     14  *    documentation and/or other materials provided with the distribution.
     15  * 3. Neither the name of the project nor the names of its contributors
     16  *    may be used to endorse or promote products derived from this software
     17  *    without specific prior written permission.
     18  *
     19  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
     20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
     23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     29  * SUCH DAMAGE.
     30  */
     31 
     32 /*
     33  * Copyright (c) 1982, 1986, 1988, 1993
     34  *	The Regents of the University of California.  All rights reserved.
     35  *
     36  * Redistribution and use in source and binary forms, with or without
     37  * modification, are permitted provided that the following conditions
     38  * are met:
     39  * 1. Redistributions of source code must retain the above copyright
     40  *    notice, this list of conditions and the following disclaimer.
     41  * 2. Redistributions in binary form must reproduce the above copyright
     42  *    notice, this list of conditions and the following disclaimer in the
     43  *    documentation and/or other materials provided with the distribution.
     44  * 3. All advertising materials mentioning features or use of this software
     45  *    must display the following acknowledgement:
     46  *	This product includes software developed by the University of
     47  *	California, Berkeley and its contributors.
     48  * 4. Neither the name of the University nor the names of its contributors
     49  *    may be used to endorse or promote products derived from this software
     50  *    without specific prior written permission.
     51  *
     52  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     53  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     54  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     55  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     56  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     57  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     58  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     59  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     60  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     61  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     62  * SUCH DAMAGE.
     63  *
     64  *	@(#)ip_icmp.c	8.2 (Berkeley) 1/4/94
     65  */
     66 
     67 #include "opt_inet.h"
     68 #include "opt_ipsec.h"
     69 
     70 #include <sys/param.h>
     71 #include <sys/systm.h>
     72 #include <sys/malloc.h>
     73 #include <sys/mbuf.h>
     74 #include <sys/protosw.h>
     75 #include <sys/socket.h>
     76 #include <sys/socketvar.h>
     77 #include <sys/time.h>
     78 #include <sys/kernel.h>
     79 #include <sys/syslog.h>
     80 #include <sys/domain.h>
     81 
     82 #include <net/if.h>
     83 #include <net/route.h>
     84 #include <net/if_dl.h>
     85 #include <net/if_types.h>
     86 
     87 #include <netinet/in.h>
     88 #include <netinet/in_var.h>
     89 #include <netinet/ip6.h>
     90 #include <netinet6/ip6_var.h>
     91 #include <netinet/icmp6.h>
     92 #include <netinet6/mld6_var.h>
     93 #include <netinet6/in6_pcb.h>
     94 #include <netinet6/nd6.h>
     95 #include <netinet6/in6_ifattach.h>
     96 #include <netinet6/ip6protosw.h>
     97 
     98 
     99 #ifdef IPSEC
    100 #include <netinet6/ipsec.h>
    101 #include <netkey/key.h>
    102 #include <netkey/key_debug.h>
    103 #endif
    104 
    105 #include "faith.h"
    106 
    107 #include <net/net_osdep.h>
    108 
    109 extern struct domain inet6domain;
    110 
    111 struct icmp6stat icmp6stat;
    112 
    113 extern struct in6pcb rawin6pcb;
    114 extern struct timeval icmp6errratelim;
    115 extern int icmp6_nodeinfo;
    116 static struct rttimer_queue *icmp6_mtudisc_timeout_q = NULL;
    117 extern int pmtu_expire;
    118 
    119 static int icmp6_rip6_input __P((struct mbuf **, int));
    120 static int icmp6_ratelimit __P((const struct in6_addr *, const int, const int));
    121 static const char *icmp6_redirect_diag __P((struct in6_addr *,
    122 	struct in6_addr *, struct in6_addr *));
    123 static struct mbuf * ni6_input __P((struct mbuf *, int));
    124 static int ni6_addrs __P((struct icmp6_nodeinfo *, struct mbuf *,
    125 			  struct ifnet **));
    126 static int ni6_store_addrs __P((struct icmp6_nodeinfo *, struct icmp6_nodeinfo *,
    127 				struct ifnet *, int));
    128 static struct rtentry *icmp6_mtudisc_clone __P((struct sockaddr *));
    129 static void icmp6_mtudisc_timeout __P((struct rtentry *, struct rttimer *));
    130 
    131 #ifdef COMPAT_RFC1885
    132 static struct route_in6 icmp6_reflect_rt;
    133 #endif
    134 
    135 void
    136 icmp6_init()
    137 {
    138 	mld6_init();
    139 	icmp6_mtudisc_timeout_q = rt_timer_queue_create(pmtu_expire);
    140 }
    141 
    142 /*
    143  * Generate an error packet of type error in response to bad IP6 packet.
    144  */
    145 void
    146 icmp6_error(m, type, code, param)
    147 	struct mbuf *m;
    148 	int type, code, param;
    149 {
    150 	struct ip6_hdr *oip6, *nip6;
    151 	struct icmp6_hdr *icmp6;
    152 	u_int preplen;
    153 	int off;
    154 	u_char nxt;
    155 
    156 	icmp6stat.icp6s_error++;
    157 
    158 #ifdef M_DECRYPTED	/*not openbsd*/
    159 	if (m->m_flags & M_DECRYPTED)
    160 		goto freeit;
    161 #endif
    162 
    163 #ifndef PULLDOWN_TEST
    164 	IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), );
    165 #else
    166 	if (m->m_len < sizeof(struct ip6_hdr)) {
    167 		m = m_pullup(m, sizeof(struct ip6_hdr));
    168 		if (m == NULL)
    169 			return;
    170 	}
    171 #endif
    172 	oip6 = mtod(m, struct ip6_hdr *);
    173 
    174 	/*
    175 	 * Multicast destination check. For unrecognized option errors,
    176 	 * this check has already done in ip6_unknown_opt(), so we can
    177 	 * check only for other errors.
    178 	 */
    179 	if ((m->m_flags & (M_BCAST|M_MCAST) ||
    180 	     IN6_IS_ADDR_MULTICAST(&oip6->ip6_dst)) &&
    181 	    (type != ICMP6_PACKET_TOO_BIG &&
    182 	     (type != ICMP6_PARAM_PROB ||
    183 	      code != ICMP6_PARAMPROB_OPTION)))
    184 		goto freeit;
    185 
    186 	/* Source address check. XXX: the case of anycast source? */
    187 	if (IN6_IS_ADDR_UNSPECIFIED(&oip6->ip6_src) ||
    188 	    IN6_IS_ADDR_MULTICAST(&oip6->ip6_src))
    189 		goto freeit;
    190 
    191 	/*
    192 	 * If the erroneous packet is also an ICMP error, discard it.
    193 	 */
    194 	off = sizeof(struct ip6_hdr);
    195 	nxt = oip6->ip6_nxt;
    196 	while (1) {		/* XXX: should avoid inf. loop explicitly? */
    197 		struct ip6_ext *ip6e;
    198 		struct icmp6_hdr *icp;
    199 
    200 		switch(nxt) {
    201 		case IPPROTO_IPV6:
    202 		case IPPROTO_IPV4:
    203 		case IPPROTO_UDP:
    204 		case IPPROTO_TCP:
    205 		case IPPROTO_ESP:
    206 		case IPPROTO_IPCOMP:
    207 		case IPPROTO_FRAGMENT:
    208 			/*
    209 			 * ICMPv6 error must not be fragmented.
    210 			 * XXX: but can we trust the sender?
    211 			 */
    212 		default:
    213 			/* What if unknown header followed by ICMP error? */
    214 			goto generate;
    215 		case IPPROTO_ICMPV6:
    216 #ifndef PULLDOWN_TEST
    217 			IP6_EXTHDR_CHECK(m, 0, off + sizeof(struct icmp6_hdr), );
    218 			icp = (struct icmp6_hdr *)(mtod(m, caddr_t) + off);
    219 #else
    220 			IP6_EXTHDR_GET(icp, struct icmp6_hdr *, m, off,
    221 				sizeof(*icp));
    222 			if (icp == NULL) {
    223 				icmp6stat.icp6s_tooshort++;
    224 				return;
    225 			}
    226 #endif
    227 			if (icp->icmp6_type < ICMP6_ECHO_REQUEST
    228 			 || icp->icmp6_type == ND_REDIRECT) {
    229 				/*
    230 				 * ICMPv6 error
    231 				 * Special case: for redirect (which is
    232 				 * informational) we must not send icmp6 error.
    233 				 */
    234 				icmp6stat.icp6s_canterror++;
    235 				goto freeit;
    236 			} else {
    237 				/* ICMPv6 informational */
    238 				goto generate;
    239 			}
    240 		case IPPROTO_HOPOPTS:
    241 		case IPPROTO_DSTOPTS:
    242 		case IPPROTO_ROUTING:
    243 		case IPPROTO_AH:
    244 #ifndef PULLDOWN_TEST
    245 			IP6_EXTHDR_CHECK(m, 0, off + sizeof(struct ip6_ext), );
    246 			ip6e = (struct ip6_ext *)(mtod(m, caddr_t) + off);
    247 #else
    248 			IP6_EXTHDR_GET(ip6e, struct ip6_ext *, m, off,
    249 				sizeof(*ip6e));
    250 			if (ip6e == NULL) {
    251 				/*XXX stat */
    252 				return;
    253 			}
    254 #endif
    255 			if (nxt == IPPROTO_AH)
    256 				off += (ip6e->ip6e_len + 2) << 2;
    257 			else
    258 				off += (ip6e->ip6e_len + 1) << 3;
    259 			nxt = ip6e->ip6e_nxt;
    260 			break;
    261 		}
    262 	}
    263 
    264   freeit:
    265 	/*
    266 	 * If we can't tell wheter or not we can generate ICMP6, free it.
    267 	 */
    268 	m_freem(m);
    269 	return;
    270 
    271   generate:
    272 	oip6 = mtod(m, struct ip6_hdr *); /* adjust pointer */
    273 
    274 	/* Finally, do rate limitation check. */
    275 	if (icmp6_ratelimit(&oip6->ip6_src, type, code)) {
    276 		icmp6stat.icp6s_toofreq++;
    277 		goto freeit;
    278 	}
    279 
    280 	/*
    281 	 * OK, ICMP6 can be generated.
    282 	 */
    283 
    284 	if (m->m_pkthdr.len >= ICMPV6_PLD_MAXLEN)
    285 		m_adj(m, ICMPV6_PLD_MAXLEN - m->m_pkthdr.len);
    286 
    287 	preplen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr);
    288 	M_PREPEND(m, preplen, M_DONTWAIT);
    289 	if (m && m->m_len < preplen)
    290 		m = m_pullup(m, preplen);
    291 	if (m == NULL) {
    292 		printf("ENOBUFS in icmp6_error %d\n", __LINE__);
    293 		return;
    294 	}
    295 
    296 	nip6 = mtod(m, struct ip6_hdr *);
    297 	nip6->ip6_src  = oip6->ip6_src;
    298 	nip6->ip6_dst  = oip6->ip6_dst;
    299 
    300 	if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_src))
    301 		oip6->ip6_src.s6_addr16[1] = 0;
    302 	if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_dst))
    303 		oip6->ip6_dst.s6_addr16[1] = 0;
    304 
    305 	icmp6 = (struct icmp6_hdr *)(nip6 + 1);
    306 	icmp6->icmp6_type = type;
    307 	icmp6->icmp6_code = code;
    308 	icmp6->icmp6_pptr = htonl((u_int32_t)param);
    309 
    310 	icmp6stat.icp6s_outhist[type]++;
    311 	icmp6_reflect(m, sizeof(struct ip6_hdr)); /*header order: IPv6 - ICMPv6*/
    312 }
    313 
    314 /*
    315  * Process a received ICMP6 message.
    316  */
    317 int
    318 icmp6_input(mp, offp, proto)
    319 	struct mbuf **mp;
    320 	int *offp, proto;
    321 {
    322 	struct mbuf *m = *mp, *n;
    323 	struct ip6_hdr *ip6, *nip6;
    324 	struct icmp6_hdr *icmp6, *nicmp6;
    325 	int off = *offp;
    326 	int icmp6len = m->m_pkthdr.len - *offp;
    327 	int code, sum, noff;
    328 	struct sockaddr_in6 icmp6src;
    329 
    330 #ifndef PULLDOWN_TEST
    331 	IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_hdr), IPPROTO_DONE);
    332 	/* m might change if M_LOOP. So, call mtod after this */
    333 #endif
    334 
    335 	/*
    336 	 * Locate icmp6 structure in mbuf, and check
    337 	 * that not corrupted and of at least minimum length
    338 	 */
    339 
    340 	ip6 = mtod(m, struct ip6_hdr *);
    341 	if (icmp6len < sizeof(struct icmp6_hdr)) {
    342 		icmp6stat.icp6s_tooshort++;
    343 		goto freeit;
    344 	}
    345 
    346 	/*
    347 	 * calculate the checksum
    348 	 */
    349 #ifndef PULLDOWN_TEST
    350 	icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off);
    351 #else
    352 	IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6));
    353 	if (icmp6 == NULL) {
    354 		icmp6stat.icp6s_tooshort++;
    355 		return IPPROTO_DONE;
    356 	}
    357 #endif
    358 	code = icmp6->icmp6_code;
    359 
    360 	if ((sum = in6_cksum(m, IPPROTO_ICMPV6, off, icmp6len)) != 0) {
    361 		log(LOG_ERR,
    362 		    "ICMP6 checksum error(%d|%x) %s\n",
    363 		    icmp6->icmp6_type,
    364 		    sum,
    365 		    ip6_sprintf(&ip6->ip6_src));
    366 		icmp6stat.icp6s_checksum++;
    367 		goto freeit;
    368 	}
    369 
    370 #if defined(NFAITH) && 0 < NFAITH
    371 	if (m->m_pkthdr.rcvif && m->m_pkthdr.rcvif->if_type == IFT_FAITH) {
    372 		/*
    373 		 * Deliver very specific ICMP6 type only.
    374 		 * This is important to deilver TOOBIG.  Otherwise PMTUD
    375 		 * will not work.
    376 		 */
    377 		switch (icmp6->icmp6_type) {
    378 		case ICMP6_DST_UNREACH:
    379 		case ICMP6_PACKET_TOO_BIG:
    380 		case ICMP6_TIME_EXCEEDED:
    381 			break;
    382 		default:
    383 			goto freeit;
    384 		}
    385 	}
    386 #endif
    387 
    388 #ifdef IPSEC
    389 	/* drop it if it does not match the default policy */
    390 	if (ipsec6_in_reject(m, NULL)) {
    391 		ipsecstat.in_polvio++;
    392 		goto freeit;
    393 	}
    394 #endif
    395 
    396 	icmp6stat.icp6s_inhist[icmp6->icmp6_type]++;
    397 	icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_msg);
    398 	if (icmp6->icmp6_type < ICMP6_INFOMSG_MASK)
    399 		icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_error);
    400 
    401 	switch (icmp6->icmp6_type) {
    402 
    403 	case ICMP6_DST_UNREACH:
    404 		icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_dstunreach);
    405 		switch (code) {
    406 		case ICMP6_DST_UNREACH_NOROUTE:
    407 			code = PRC_UNREACH_NET;
    408 			break;
    409 		case ICMP6_DST_UNREACH_ADMIN:
    410 			icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_adminprohib);
    411 		case ICMP6_DST_UNREACH_ADDR:
    412 			code = PRC_UNREACH_HOST;
    413 			break;
    414 		case ICMP6_DST_UNREACH_NOTNEIGHBOR:
    415 			code = PRC_UNREACH_SRCFAIL;
    416 			break;
    417 		case ICMP6_DST_UNREACH_NOPORT:
    418 			code = PRC_UNREACH_PORT;
    419 			break;
    420 		default:
    421 			goto badcode;
    422 		}
    423 		goto deliver;
    424 		break;
    425 
    426 	case ICMP6_PACKET_TOO_BIG:
    427 		icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_pkttoobig);
    428 		if (code != 0)
    429 			goto badcode;
    430 	    {
    431 		u_int mtu = ntohl(icmp6->icmp6_mtu);
    432 		struct rtentry *rt = NULL;
    433 		struct sockaddr_in6 sin6;
    434 
    435 		if (icmp6len < sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr)) {
    436 			icmp6stat.icp6s_tooshort++;
    437 			goto freeit;
    438 		}
    439 #ifndef PULLDOWN_TEST
    440 		IP6_EXTHDR_CHECK(m, off,
    441 			sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr),
    442 			IPPROTO_DONE);
    443 		icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off);
    444 #else
    445 		IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off,
    446 			sizeof(*icmp6) + sizeof(struct ip6_hdr));
    447 		if (icmp6 == NULL) {
    448 			icmp6stat.icp6s_tooshort++;
    449 			return IPPROTO_DONE;
    450 		}
    451 #endif
    452 		code = PRC_MSGSIZE;
    453 		bzero(&sin6, sizeof(sin6));
    454 		sin6.sin6_family = PF_INET6;
    455 		sin6.sin6_len = sizeof(struct sockaddr_in6);
    456 		sin6.sin6_addr = ((struct ip6_hdr *)(icmp6 + 1))->ip6_dst;
    457 		rt = rtalloc1((struct sockaddr *)&sin6, 1);	/*clone*/
    458 		if (!rt || (rt->rt_flags & RTF_HOST) == 0) {
    459 			if (rt)
    460 				RTFREE(rt);
    461 			rt = icmp6_mtudisc_clone((struct sockaddr *)&sin6);
    462 		}
    463 
    464 		if (rt && (rt->rt_flags & RTF_HOST)
    465 		    && !(rt->rt_rmx.rmx_locks & RTV_MTU)) {
    466 			if (mtu < IPV6_MMTU) {
    467 				/* xxx */
    468 				rt->rt_rmx.rmx_locks |= RTV_MTU;
    469 			} else if (mtu < rt->rt_ifp->if_mtu &&
    470 				   rt->rt_rmx.rmx_mtu > mtu) {
    471 				rt->rt_rmx.rmx_mtu = mtu;
    472 			}
    473 		}
    474 		if (rt)
    475 			RTFREE(rt);
    476 
    477 		goto deliver;
    478 	    }
    479 		break;
    480 
    481 	case ICMP6_TIME_EXCEEDED:
    482 		icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_timeexceed);
    483 		switch (code) {
    484 		case ICMP6_TIME_EXCEED_TRANSIT:
    485 		case ICMP6_TIME_EXCEED_REASSEMBLY:
    486 			code += PRC_TIMXCEED_INTRANS;
    487 			break;
    488 		default:
    489 			goto badcode;
    490 		}
    491 		goto deliver;
    492 		break;
    493 
    494 	case ICMP6_PARAM_PROB:
    495 		icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_paramprob);
    496 		switch (code) {
    497 		case ICMP6_PARAMPROB_NEXTHEADER:
    498 			code = PRC_UNREACH_PROTOCOL;
    499 			break;
    500 		case ICMP6_PARAMPROB_HEADER:
    501 		case ICMP6_PARAMPROB_OPTION:
    502 			code = PRC_PARAMPROB;
    503 			break;
    504 		default:
    505 			goto badcode;
    506 		}
    507 		goto deliver;
    508 		break;
    509 
    510 	case ICMP6_ECHO_REQUEST:
    511 		icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echo);
    512 		if (code != 0)
    513 			goto badcode;
    514 		if ((n = m_copy(m, 0, M_COPYALL)) == NULL) {
    515 			/* Give up remote */
    516 			break;
    517 		}
    518 		if ((n->m_flags & M_EXT) != 0
    519 		 || n->m_len < off + sizeof(struct icmp6_hdr)) {
    520 			struct mbuf *n0 = n;
    521 
    522 			/*
    523 			 * Prepare an internal mbuf. m_pullup() doesn't
    524 			 * always copy the length we specified.
    525 			 */
    526 			MGETHDR(n, M_DONTWAIT, n0->m_type);
    527 			if (n == NULL) {
    528 				/* Give up remote */
    529 				m_freem(n0);
    530 				break;
    531 			}
    532 			M_COPY_PKTHDR(n, n0);
    533 			/*
    534 			 * Copy IPv6 and ICMPv6 only.
    535 			 */
    536 			nip6 = mtod(n, struct ip6_hdr *);
    537 			bcopy(ip6, nip6, sizeof(struct ip6_hdr));
    538 			nicmp6 = (struct icmp6_hdr *)(nip6 + 1);
    539 			bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr));
    540 			noff = sizeof(struct ip6_hdr);
    541 			n->m_pkthdr.len = n->m_len =
    542 				noff + sizeof(struct icmp6_hdr);
    543 			/*
    544 			 * Adjust mbuf. ip6_plen will be adjusted in
    545 			 * ip6_output().
    546 			 */
    547 			m_adj(n0, off + sizeof(struct icmp6_hdr));
    548 			n->m_pkthdr.len += n0->m_pkthdr.len;
    549 			n->m_next = n0;
    550 			n0->m_flags &= ~M_PKTHDR;
    551 		} else {
    552 			nip6 = mtod(n, struct ip6_hdr *);
    553 			nicmp6 = (struct icmp6_hdr *)((caddr_t)nip6 + off);
    554 			noff = off;
    555 		}
    556 		nicmp6->icmp6_type = ICMP6_ECHO_REPLY;
    557 		nicmp6->icmp6_code = 0;
    558 		if (n) {
    559 			icmp6stat.icp6s_reflect++;
    560 			icmp6stat.icp6s_outhist[ICMP6_ECHO_REPLY]++;
    561 			icmp6_reflect(n, noff);
    562 		}
    563 		break;
    564 
    565 	case ICMP6_ECHO_REPLY:
    566 		icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echoreply);
    567 		if (code != 0)
    568 			goto badcode;
    569 		break;
    570 
    571 	case MLD6_LISTENER_QUERY:
    572 	case MLD6_LISTENER_REPORT:
    573 		if (icmp6len < sizeof(struct mld6_hdr))
    574 			goto badlen;
    575 		if (icmp6->icmp6_type == MLD6_LISTENER_QUERY) /* XXX: ugly... */
    576 			icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldquery);
    577 		else
    578 			icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldreport);
    579 		IP6_EXTHDR_CHECK(m, off, icmp6len, IPPROTO_DONE);
    580 		mld6_input(m, off);
    581 		/* m stays. */
    582 		break;
    583 
    584 	case MLD6_LISTENER_DONE:
    585 		icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mlddone);
    586 		if (icmp6len < sizeof(struct mld6_hdr))	/* necessary? */
    587 			goto badlen;
    588 		break;		/* nothing to be done in kernel */
    589 
    590 	case MLD6_MTRACE_RESP:
    591 	case MLD6_MTRACE:
    592 		/* XXX: these two are experimental. not officially defind. */
    593 		/* XXX: per-interface statistics? */
    594 		break;		/* just pass it to the userland daemon */
    595 
    596 	case ICMP6_WRUREQUEST:	/* ICMP6_FQDN_QUERY */
    597 	    {
    598 		enum { WRU, FQDN } mode;
    599 
    600 		if (code != 0)
    601 			goto badcode;
    602 		if (!icmp6_nodeinfo)
    603 			break;
    604 
    605 		if (icmp6len == sizeof(struct icmp6_hdr) + 4)
    606 			mode = WRU;
    607 		else if (icmp6len >= sizeof(struct icmp6_hdr) + 8) /* XXX */
    608 			mode = FQDN;
    609 		else
    610 			goto badlen;
    611 
    612 		if (mode == FQDN) {
    613 #ifndef PULLDOWN_TEST
    614 			IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_nodeinfo),
    615 					 IPPROTO_DONE);
    616 #endif
    617 			n = m_copy(m, 0, M_COPYALL);
    618 			if (n)
    619 				n = ni6_input(n, off);
    620 			if (n)
    621 				noff = sizeof(struct ip6_hdr);
    622 		} else {
    623 			u_char *p;
    624 
    625 			MGETHDR(n, M_DONTWAIT, m->m_type);
    626 			if (n == NULL) {
    627 				/* Give up remote */
    628 				break;
    629 			}
    630 			/*
    631 			 * Copy IPv6 and ICMPv6 only.
    632 			 */
    633 			nip6 = mtod(n, struct ip6_hdr *);
    634 			bcopy(ip6, nip6, sizeof(struct ip6_hdr));
    635 			nicmp6 = (struct icmp6_hdr *)(nip6 + 1);
    636 			bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr));
    637 			p = (u_char *)(nicmp6 + 1);
    638 			bzero(p, 4);
    639 			bcopy(hostname, p + 4, hostnamelen);
    640 			noff = sizeof(struct ip6_hdr);
    641 			M_COPY_PKTHDR(n, m); /* just for recvif */
    642 			n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) +
    643 				sizeof(struct icmp6_hdr) + 4 + hostnamelen;
    644 			nicmp6->icmp6_type = ICMP6_WRUREPLY;
    645 			nicmp6->icmp6_code = 0;
    646 		}
    647 #undef hostnamelen
    648 		if (n) {
    649 			icmp6stat.icp6s_reflect++;
    650 			icmp6stat.icp6s_outhist[ICMP6_WRUREPLY]++;
    651 			icmp6_reflect(n, noff);
    652 		}
    653 		break;
    654 	    }
    655 
    656 	case ICMP6_WRUREPLY:
    657 		if (code != 0)
    658 			goto badcode;
    659 		break;
    660 
    661 	case ND_ROUTER_SOLICIT:
    662 		icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routersolicit);
    663 		if (code != 0)
    664 			goto badcode;
    665 		if (icmp6len < sizeof(struct nd_router_solicit))
    666 			goto badlen;
    667 		IP6_EXTHDR_CHECK(m, off, icmp6len, IPPROTO_DONE);
    668 		nd6_rs_input(m, off, icmp6len);
    669 		/* m stays. */
    670 		break;
    671 
    672 	case ND_ROUTER_ADVERT:
    673 		icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routeradvert);
    674 		if (code != 0)
    675 			goto badcode;
    676 		if (icmp6len < sizeof(struct nd_router_advert))
    677 			goto badlen;
    678 		IP6_EXTHDR_CHECK(m, off, icmp6len, IPPROTO_DONE);
    679 		nd6_ra_input(m, off, icmp6len);
    680 		/* m stays. */
    681 		break;
    682 
    683 	case ND_NEIGHBOR_SOLICIT:
    684 		icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighborsolicit);
    685 		if (code != 0)
    686 			goto badcode;
    687 		if (icmp6len < sizeof(struct nd_neighbor_solicit))
    688 			goto badlen;
    689 		IP6_EXTHDR_CHECK(m, off, icmp6len, IPPROTO_DONE);
    690 		nd6_ns_input(m, off, icmp6len);
    691 		/* m stays. */
    692 		break;
    693 
    694 	case ND_NEIGHBOR_ADVERT:
    695 		icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighboradvert);
    696 		if (code != 0)
    697 			goto badcode;
    698 		if (icmp6len < sizeof(struct nd_neighbor_advert))
    699 			goto badlen;
    700 		IP6_EXTHDR_CHECK(m, off, icmp6len, IPPROTO_DONE);
    701 		nd6_na_input(m, off, icmp6len);
    702 		/* m stays. */
    703 		break;
    704 
    705 	case ND_REDIRECT:
    706 		icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_redirect);
    707 		if (code != 0)
    708 			goto badcode;
    709 		if (icmp6len < sizeof(struct nd_redirect))
    710 			goto badlen;
    711 		icmp6_redirect_input(m, off);
    712 		/* m stays. */
    713 		break;
    714 
    715 	case ICMP6_ROUTER_RENUMBERING:
    716 		if (code != ICMP6_ROUTER_RENUMBERING_COMMAND &&
    717 		    code != ICMP6_ROUTER_RENUMBERING_RESULT)
    718 			goto badcode;
    719 		if (icmp6len < sizeof(struct icmp6_router_renum))
    720 			goto badlen;
    721 		break;
    722 
    723 	default:
    724 		printf("icmp6_input: unknown type %d(src=%s, dst=%s, ifid=%d)\n",
    725 		       icmp6->icmp6_type, ip6_sprintf(&ip6->ip6_src),
    726 		       ip6_sprintf(&ip6->ip6_dst),
    727 		       m->m_pkthdr.rcvif ? m->m_pkthdr.rcvif->if_index : 0);
    728 		if (icmp6->icmp6_type < ICMP6_ECHO_REQUEST) {
    729 			/* ICMPv6 error: MUST deliver it by spec... */
    730 			code = PRC_NCMDS;
    731 			/* deliver */
    732 		} else {
    733 			/* ICMPv6 informational: MUST not deliver */
    734 			break;
    735 		}
    736 	deliver:
    737 		if (icmp6len < sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr)) {
    738 			icmp6stat.icp6s_tooshort++;
    739 			goto freeit;
    740 		}
    741 #ifndef PULLDOWN_TEST
    742 		IP6_EXTHDR_CHECK(m, off,
    743 			sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr),
    744 			IPPROTO_DONE);
    745 		icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off);
    746 #else
    747 		IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off,
    748 			sizeof(*icmp6) + sizeof(struct ip6_hdr));
    749 		if (icmp6 == NULL) {
    750 			icmp6stat.icp6s_tooshort++;
    751 			return IPPROTO_DONE;
    752 		}
    753 #endif
    754 		bzero(&icmp6src, sizeof(icmp6src));
    755 		icmp6src.sin6_len = sizeof(struct sockaddr_in6);
    756 		icmp6src.sin6_family = AF_INET6;
    757 		icmp6src.sin6_addr = ((struct ip6_hdr *)(icmp6 + 1))->ip6_dst;
    758 
    759 		/* Detect the upper level protocol */
    760 	    {
    761 		void (*ctlfunc) __P((int, struct sockaddr *, void *));
    762 		struct ip6_hdr *eip6 = (struct ip6_hdr *)(icmp6 + 1);
    763 		u_int8_t nxt = eip6->ip6_nxt;
    764 		int eoff = off + sizeof(struct icmp6_hdr) +
    765 			sizeof(struct ip6_hdr);
    766 		struct ip6ctlparam ip6cp;
    767 
    768 		while (1) { /* XXX: should avoid inf. loop explicitly? */
    769 			struct ip6_ext *eh;
    770 
    771 			switch(nxt) {
    772 			case IPPROTO_ESP:
    773 			case IPPROTO_NONE:
    774 				goto passit;
    775 			case IPPROTO_HOPOPTS:
    776 			case IPPROTO_DSTOPTS:
    777 			case IPPROTO_ROUTING:
    778 			case IPPROTO_AH:
    779 			case IPPROTO_FRAGMENT:
    780 #ifndef PULLDOWN_TEST
    781 				IP6_EXTHDR_CHECK(m, 0, eoff +
    782 						 sizeof(struct ip6_ext),
    783 						 IPPROTO_DONE);
    784 				eh = (struct ip6_ext *)(mtod(m, caddr_t)
    785 							+ eoff);
    786 #else
    787 				IP6_EXTHDR_GET(eh, struct ip6_ext *, m,
    788 					eoff, sizeof(*eh));
    789 				if (eh == NULL) {
    790 					icmp6stat.icp6s_tooshort++;
    791 					return IPPROTO_DONE;
    792 				}
    793 #endif
    794 				if (nxt == IPPROTO_AH)
    795 					eoff += (eh->ip6e_len + 2) << 2;
    796 				else if (nxt == IPPROTO_FRAGMENT)
    797 					eoff += sizeof(struct ip6_frag);
    798 				else
    799 					eoff += (eh->ip6e_len + 1) << 3;
    800 				nxt = eh->ip6e_nxt;
    801 				break;
    802 			default:
    803 				goto notify;
    804 			}
    805 		}
    806 	    notify:
    807 #ifndef PULLDOWN_TEST
    808 		icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off);
    809 #else
    810 		IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off,
    811 			sizeof(*icmp6) + sizeof(struct ip6_hdr));
    812 		if (icmp6 == NULL) {
    813 			icmp6stat.icp6s_tooshort++;
    814 			return IPPROTO_DONE;
    815 		}
    816 #endif
    817 		ctlfunc = (void (*) __P((int, struct sockaddr *, void *)))
    818 			(inet6sw[ip6_protox[nxt]].pr_ctlinput);
    819 		if (ctlfunc) {
    820 			ip6cp.ip6c_m = m;
    821 			ip6cp.ip6c_ip6 = (struct ip6_hdr *)(icmp6 + 1);
    822 			ip6cp.ip6c_off = eoff;
    823 			(*ctlfunc)(code, (struct sockaddr *)&icmp6src, &ip6cp);
    824 		}
    825 	    }
    826 		break;
    827 
    828 	badcode:
    829 		icmp6stat.icp6s_badcode++;
    830 		break;
    831 
    832 	badlen:
    833 		icmp6stat.icp6s_badlen++;
    834 		break;
    835 	}
    836 
    837  passit:
    838 	icmp6_rip6_input(&m, *offp);
    839 	return IPPROTO_DONE;
    840 
    841  freeit:
    842 	m_freem(m);
    843 	return IPPROTO_DONE;
    844 }
    845 
    846 /*
    847  * Process a Node Information Query
    848  */
    849 #ifndef offsetof		/* XXX */
    850 #define	offsetof(type, member)	((size_t)(&((type *)0)->member))
    851 #endif
    852 
    853 static struct mbuf *
    854 ni6_input(m, off)
    855 	struct mbuf *m;
    856 	int off;
    857 {
    858 	struct icmp6_nodeinfo *ni6, *nni6;
    859 	struct mbuf *n = NULL;
    860 	u_int16_t qtype;
    861 	int replylen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo);
    862 	struct ni_reply_fqdn *fqdn;
    863 	int addrs;		/* for NI_QTYPE_NODEADDR */
    864 	struct ifnet *ifp = NULL; /* for NI_QTYPE_NODEADDR */
    865 
    866 #ifndef PULLDOWN_TEST
    867 	ni6 = (struct icmp6_nodeinfo *)(mtod(m, caddr_t) + off);
    868 #else
    869 	IP6_EXTHDR_GET(ni6, struct icmp6_nodeinfo *, m, off, sizeof(*ni6));
    870 	if (ni6 == NULL) {
    871 		/* m is already reclaimed */
    872 		return NULL;
    873 	}
    874 #endif
    875 	qtype = ntohs(ni6->ni_qtype);
    876 
    877 	switch(qtype) {
    878 	 case NI_QTYPE_NOOP:
    879 		 break;		/* no reply data */
    880 	 case NI_QTYPE_SUPTYPES:
    881 		 goto bad;	/* xxx: to be implemented */
    882 		 break;
    883 	 case NI_QTYPE_FQDN:
    884 		 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_name) +
    885 			 hostnamelen;
    886 		 break;
    887 	 case NI_QTYPE_NODEADDR:
    888 		 addrs = ni6_addrs(ni6, m, &ifp);
    889 		 if ((replylen += addrs * sizeof(struct in6_addr)) > MCLBYTES)
    890 			 replylen = MCLBYTES; /* XXX: we'll truncate later */
    891 
    892 		 break;
    893 	 default:
    894 		 /*
    895 		  * XXX: We must return a reply with the ICMP6 code
    896 		  * `unknown Qtype' in this case. However we regard the case
    897 		  * as an FQDN query for backward compatibility.
    898 		  * Older versions set a random value to this field,
    899 		  * so it rarely varies in the defined qtypes.
    900 		  * But the mechanism is not reliable...
    901 		  * maybe we should obsolete older versions.
    902 		  */
    903 		 qtype = NI_QTYPE_FQDN;
    904 		 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_name) +
    905 			 hostnamelen;
    906 		 break;
    907 	}
    908 
    909 	/* allocate a mbuf to reply. */
    910 	MGETHDR(n, M_DONTWAIT, m->m_type);
    911 	if (n == NULL) {
    912 		m_freem(m);
    913 		return(NULL);
    914 	}
    915 	M_COPY_PKTHDR(n, m); /* just for recvif */
    916 	if (replylen > MHLEN) {
    917 		if (replylen > MCLBYTES)
    918 			 /*
    919 			  * XXX: should we try to allocate more? But MCLBYTES is
    920 			  * probably much larger than IPV6_MMTU...
    921 			  */
    922 			goto bad;
    923 		MCLGET(n, M_DONTWAIT);
    924 		if ((n->m_flags & M_EXT) == 0) {
    925 			goto bad;
    926 		}
    927 	}
    928 	n->m_pkthdr.len = n->m_len = replylen;
    929 
    930 	/* copy mbuf header and IPv6 + Node Information base headers */
    931 	bcopy(mtod(m, caddr_t), mtod(n, caddr_t), sizeof(struct ip6_hdr));
    932 	nni6 = (struct icmp6_nodeinfo *)(mtod(n, struct ip6_hdr *) + 1);
    933 	bcopy((caddr_t)ni6, (caddr_t)nni6, sizeof(struct icmp6_nodeinfo));
    934 
    935 	/* qtype dependent procedure */
    936 	switch (qtype) {
    937 	 case NI_QTYPE_NOOP:
    938 		 nni6->ni_flags = 0;
    939 		 break;
    940 	 case NI_QTYPE_SUPTYPES:
    941 		 goto bad;	/* xxx: to be implemented */
    942 		 break;
    943 	 case NI_QTYPE_FQDN:
    944 		 if (hostnamelen > 255) { /* XXX: rare case, but may happen */
    945 			 printf("ni6_input: "
    946 				"hostname length(%d) is too large for reply\n",
    947 				hostnamelen);
    948 			 goto bad;
    949 		 }
    950 		 fqdn = (struct ni_reply_fqdn *)(mtod(n, caddr_t) +
    951 						 sizeof(struct ip6_hdr) +
    952 						 sizeof(struct icmp6_nodeinfo));
    953 		 nni6->ni_flags = 0; /* XXX: meaningless TTL */
    954 		 fqdn->ni_fqdn_ttl = 0;	/* ditto. */
    955 		 fqdn->ni_fqdn_namelen = hostnamelen;
    956 		 bcopy(hostname, &fqdn->ni_fqdn_name[0], hostnamelen);
    957 		 break;
    958 	 case NI_QTYPE_NODEADDR:
    959 	 {
    960 		 int lenlim, copied;
    961 
    962 		 if (n->m_flags & M_EXT)
    963 			 lenlim = MCLBYTES - sizeof(struct ip6_hdr) -
    964 				 sizeof(struct icmp6_nodeinfo);
    965 		 else
    966 			 lenlim = MHLEN - sizeof(struct ip6_hdr) -
    967 				 sizeof(struct icmp6_nodeinfo);
    968 		 copied = ni6_store_addrs(ni6, nni6, ifp, lenlim);
    969 		 /* XXX: reset mbuf length */
    970 		 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) +
    971 			 sizeof(struct icmp6_nodeinfo) + copied;
    972 		 break;
    973 	 }
    974 	 default:
    975 		 break;		/* XXX impossible! */
    976 	}
    977 
    978 	nni6->ni_type = ICMP6_NI_REPLY;
    979 	nni6->ni_code = ICMP6_NI_SUCESS;
    980 	m_freem(m);
    981 	return(n);
    982 
    983   bad:
    984 	m_freem(m);
    985 	if (n)
    986 		m_freem(n);
    987 	return(NULL);
    988 }
    989 #undef hostnamelen
    990 
    991 /*
    992  * calculate the number of addresses to be returned in the node info reply.
    993  */
    994 static int
    995 ni6_addrs(ni6, m, ifpp)
    996 	struct icmp6_nodeinfo *ni6;
    997 	struct mbuf *m;
    998 	struct ifnet **ifpp;
    999 {
   1000 	register struct ifnet *ifp;
   1001 	register struct in6_ifaddr *ifa6;
   1002 	register struct ifaddr *ifa;
   1003 	struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
   1004 	int addrs = 0, addrsofif, iffound = 0;
   1005 
   1006 	for (ifp = TAILQ_FIRST(&ifnet); ifp; ifp = TAILQ_NEXT(ifp, if_list))
   1007 	{
   1008 		addrsofif = 0;
   1009 		for (ifa = ifp->if_addrlist.tqh_first; ifa;
   1010 		     ifa = ifa->ifa_list.tqe_next)
   1011 		{
   1012 			if (ifa->ifa_addr->sa_family != AF_INET6)
   1013 				continue;
   1014 			ifa6 = (struct in6_ifaddr *)ifa;
   1015 
   1016 			if (!(ni6->ni_flags & NI_NODEADDR_FLAG_ALL) &&
   1017 			    IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst,
   1018 					       &ifa6->ia_addr.sin6_addr))
   1019 				iffound = 1;
   1020 
   1021 			if (ifa6->ia6_flags & IN6_IFF_ANYCAST)
   1022 				continue; /* we need only unicast addresses */
   1023 
   1024 			if ((ni6->ni_flags & (NI_NODEADDR_FLAG_LINKLOCAL |
   1025 					      NI_NODEADDR_FLAG_SITELOCAL |
   1026 					      NI_NODEADDR_FLAG_GLOBAL)) == 0)
   1027 				continue;
   1028 
   1029 			/* What do we have to do about ::1? */
   1030 			switch(in6_addrscope(&ifa6->ia_addr.sin6_addr)) {
   1031 			 case IPV6_ADDR_SCOPE_LINKLOCAL:
   1032 				if (ni6->ni_flags & NI_NODEADDR_FLAG_LINKLOCAL)
   1033 					addrsofif++;
   1034 				break;
   1035 			 case IPV6_ADDR_SCOPE_SITELOCAL:
   1036 				if (ni6->ni_flags & NI_NODEADDR_FLAG_SITELOCAL)
   1037 					addrsofif++;
   1038 				break;
   1039 			 case IPV6_ADDR_SCOPE_GLOBAL:
   1040 				 if (ni6->ni_flags & NI_NODEADDR_FLAG_GLOBAL)
   1041 					 addrsofif++;
   1042 				 break;
   1043 			 default:
   1044 				 continue;
   1045 			}
   1046 		}
   1047 		if (iffound) {
   1048 			*ifpp = ifp;
   1049 			return(addrsofif);
   1050 		}
   1051 
   1052 		addrs += addrsofif;
   1053 	}
   1054 
   1055 	return(addrs);
   1056 }
   1057 
   1058 static int
   1059 ni6_store_addrs(ni6, nni6, ifp0, resid)
   1060 	struct icmp6_nodeinfo *ni6, *nni6;
   1061 	struct ifnet *ifp0;
   1062 	int resid;
   1063 {
   1064 	register struct ifnet *ifp = ifp0 ? ifp0 : TAILQ_FIRST(&ifnet);
   1065 	register struct in6_ifaddr *ifa6;
   1066 	register struct ifaddr *ifa;
   1067 	int docopy, copied = 0;
   1068 	u_char *cp = (u_char *)(nni6 + 1);
   1069 
   1070 	if (ifp0 == NULL && !(ni6->ni_flags & NI_NODEADDR_FLAG_ALL))
   1071 		return(0);	/* needless to copy */
   1072 
   1073 	for (; ifp; ifp = TAILQ_NEXT(ifp, if_list))
   1074 	{
   1075 		for (ifa = ifp->if_addrlist.tqh_first; ifa;
   1076 		     ifa = ifa->ifa_list.tqe_next)
   1077 		{
   1078 			docopy = 0;
   1079 
   1080 			if (ifa->ifa_addr->sa_family != AF_INET6)
   1081 				continue;
   1082 			ifa6 = (struct in6_ifaddr *)ifa;
   1083 
   1084 			if (ifa6->ia6_flags & IN6_IFF_ANYCAST) {
   1085 				/* just experimental. not in the spec. */
   1086 				if (ni6->ni_flags & NI_NODEADDR_FLAG_ANYCAST)
   1087 					docopy = 1;
   1088 				else
   1089 					continue;
   1090 			}
   1091 			else {	/* unicast address */
   1092 				if (ni6->ni_flags & NI_NODEADDR_FLAG_ANYCAST)
   1093 					continue;
   1094 				else
   1095 					docopy = 1;
   1096 			}
   1097 
   1098 			/* What do we have to do about ::1? */
   1099 			switch(in6_addrscope(&ifa6->ia_addr.sin6_addr)) {
   1100 			 case IPV6_ADDR_SCOPE_LINKLOCAL:
   1101 				if (ni6->ni_flags & NI_NODEADDR_FLAG_LINKLOCAL)
   1102 					docopy = 1;
   1103 				break;
   1104 			 case IPV6_ADDR_SCOPE_SITELOCAL:
   1105 				if (ni6->ni_flags & NI_NODEADDR_FLAG_SITELOCAL)
   1106 					docopy = 1;
   1107 				break;
   1108 			 case IPV6_ADDR_SCOPE_GLOBAL:
   1109 				 if (ni6->ni_flags & NI_NODEADDR_FLAG_GLOBAL)
   1110 					 docopy = 1;
   1111 				 break;
   1112 			 default:
   1113 				 continue;
   1114 			}
   1115 
   1116 			if (docopy) {
   1117 				if (resid < sizeof(struct in6_addr)) {
   1118 					/*
   1119 					 * We give up much more copy.
   1120 					 * Set the truncate flag and return.
   1121 					 */
   1122 					nni6->ni_flags |=
   1123 						NI_NODEADDR_FLAG_TRUNCATE;
   1124 					return(copied);
   1125 				}
   1126 				bcopy(&ifa6->ia_addr.sin6_addr, cp,
   1127 				      sizeof(struct in6_addr));
   1128 				/* XXX: KAME link-local hack; remove ifindex */
   1129 				if (IN6_IS_ADDR_LINKLOCAL(&ifa6->ia_addr.sin6_addr))
   1130 					((struct in6_addr *)cp)->s6_addr16[1] = 0;
   1131 				cp += sizeof(struct in6_addr);
   1132 				resid -= sizeof(struct in6_addr);
   1133 				copied += sizeof(struct in6_addr);
   1134 			}
   1135 		}
   1136 		if (ifp0)	/* we need search only on the specified IF */
   1137 			break;
   1138 	}
   1139 
   1140 	return(copied);
   1141 }
   1142 
   1143 /*
   1144  * XXX almost dup'ed code with rip6_input.
   1145  */
   1146 static int
   1147 icmp6_rip6_input(mp, off)
   1148 	struct	mbuf **mp;
   1149 	int	off;
   1150 {
   1151 	struct mbuf *m = *mp;
   1152 	register struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
   1153 	register struct in6pcb *in6p;
   1154 	struct in6pcb *last = NULL;
   1155 	struct sockaddr_in6 rip6src;
   1156 	struct icmp6_hdr *icmp6;
   1157 	struct mbuf *opts = NULL;
   1158 
   1159 	/* this is assumed to be safe. */
   1160 	icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off);
   1161 
   1162 	bzero(&rip6src, sizeof(rip6src));
   1163 	rip6src.sin6_len = sizeof(struct sockaddr_in6);
   1164 	rip6src.sin6_family = AF_INET6;
   1165 	rip6src.sin6_addr = ip6->ip6_src;
   1166 	if (IN6_IS_SCOPE_LINKLOCAL(&rip6src.sin6_addr))
   1167 		rip6src.sin6_addr.s6_addr16[1] = 0;
   1168 	if (m->m_pkthdr.rcvif) {
   1169 		if (IN6_IS_SCOPE_LINKLOCAL(&rip6src.sin6_addr))
   1170 			rip6src.sin6_scope_id = m->m_pkthdr.rcvif->if_index;
   1171 		else
   1172 			rip6src.sin6_scope_id = 0;
   1173 	} else
   1174 		rip6src.sin6_scope_id = 0;
   1175 
   1176 	for (in6p = rawin6pcb.in6p_next;
   1177 	     in6p != &rawin6pcb; in6p = in6p->in6p_next)
   1178 	{
   1179 		if (in6p->in6p_ip6_nxt != IPPROTO_ICMPV6)
   1180 			continue;
   1181 		if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr) &&
   1182 		   !IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr, &ip6->ip6_dst))
   1183 			continue;
   1184 		if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr) &&
   1185 		   !IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr, &ip6->ip6_src))
   1186 			continue;
   1187 		if (in6p->in6p_icmp6filt
   1188 		    && ICMP6_FILTER_WILLBLOCK(icmp6->icmp6_type,
   1189 				 in6p->in6p_icmp6filt))
   1190 			continue;
   1191 		if (last) {
   1192 			struct	mbuf *n;
   1193 			if ((n = m_copy(m, 0, (int)M_COPYALL)) != NULL) {
   1194 				if (last->in6p_flags & IN6P_CONTROLOPTS)
   1195 					ip6_savecontrol(last, &opts, ip6, n);
   1196 				/* strip intermediate headers */
   1197 				m_adj(n, off);
   1198 				if (sbappendaddr(&last->in6p_socket->so_rcv,
   1199 						 (struct sockaddr *)&rip6src,
   1200 						 n, opts) == 0) {
   1201 					/* should notify about lost packet */
   1202 					m_freem(n);
   1203 					if (opts)
   1204 						m_freem(opts);
   1205 				} else
   1206 					sorwakeup(last->in6p_socket);
   1207 				opts = NULL;
   1208 			}
   1209 		}
   1210 		last = in6p;
   1211 	}
   1212 	if (last) {
   1213 		if (last->in6p_flags & IN6P_CONTROLOPTS)
   1214 			ip6_savecontrol(last, &opts, ip6, m);
   1215 		/* strip intermediate headers */
   1216 		m_adj(m, off);
   1217 		if (sbappendaddr(&last->in6p_socket->so_rcv,
   1218 				(struct sockaddr *)&rip6src, m, opts) == 0) {
   1219 			m_freem(m);
   1220 			if (opts)
   1221 				m_freem(opts);
   1222 		} else
   1223 			sorwakeup(last->in6p_socket);
   1224 	} else {
   1225 		m_freem(m);
   1226 		ip6stat.ip6s_delivered--;
   1227 	}
   1228 	return IPPROTO_DONE;
   1229 }
   1230 
   1231 /*
   1232  * Reflect the ip6 packet back to the source.
   1233  * OFF points to the icmp6 header, counted from the top of the mbuf.
   1234  */
   1235 void
   1236 icmp6_reflect(m, off)
   1237 	struct	mbuf *m;
   1238 	size_t off;
   1239 {
   1240 	struct ip6_hdr *ip6;
   1241 	struct icmp6_hdr *icmp6;
   1242 	struct in6_ifaddr *ia;
   1243 	struct in6_addr t, *src = 0;
   1244 	int plen;
   1245 	int type, code;
   1246 	struct ifnet *outif = NULL;
   1247 #ifdef COMPAT_RFC1885
   1248 	int mtu = IPV6_MMTU;
   1249 	struct sockaddr_in6 *sin6 = &icmp6_reflect_rt.ro_dst;
   1250 #endif
   1251 
   1252 	/* too short to reflect */
   1253 	if (off < sizeof(struct ip6_hdr)) {
   1254 		printf("sanity fail: off=%lx, sizeof(ip6)=%lx in %s:%d\n",
   1255 		       (u_long)off, (u_long)sizeof(struct ip6_hdr),
   1256 		       __FILE__, __LINE__);
   1257 		goto bad;
   1258 	}
   1259 
   1260 	/*
   1261 	 * If there are extra headers between IPv6 and ICMPv6, strip
   1262 	 * off that header first.
   1263 	 */
   1264 	if (off > sizeof(struct ip6_hdr)) {
   1265 		size_t l;
   1266 		struct ip6_hdr nip6;
   1267 
   1268 		l = off - sizeof(struct ip6_hdr);
   1269 		m_copydata(m, 0, sizeof(nip6), (caddr_t)&nip6);
   1270 		m_adj(m, l);
   1271 		l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr);
   1272 		if (m->m_len < l) {
   1273 			if ((m = m_pullup(m, l)) == NULL)
   1274 				return;
   1275 		}
   1276 		bcopy((caddr_t)&nip6, mtod(m, caddr_t), sizeof(nip6));
   1277 	} else /* off == sizeof(struct ip6_hdr) */ {
   1278 		size_t l;
   1279 		l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr);
   1280 		if (m->m_len < l) {
   1281 			if ((m = m_pullup(m, l)) == NULL)
   1282 				return;
   1283 		}
   1284 	}
   1285 	plen = m->m_pkthdr.len - sizeof(struct ip6_hdr);
   1286 	ip6 = mtod(m, struct ip6_hdr *);
   1287 	ip6->ip6_nxt = IPPROTO_ICMPV6;
   1288 	icmp6 = (struct icmp6_hdr *)(ip6 + 1);
   1289 	type = icmp6->icmp6_type; /* keep type for statistics */
   1290 	code = icmp6->icmp6_code; /* ditto. */
   1291 
   1292 	t = ip6->ip6_dst;
   1293 	/*
   1294 	 * ip6_input() drops a packet if its src is multicast.
   1295 	 * So, the src is never multicast.
   1296 	 */
   1297 	ip6->ip6_dst = ip6->ip6_src;
   1298 
   1299 	/* XXX hack for link-local addresses */
   1300 	if (IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_dst))
   1301 		ip6->ip6_dst.s6_addr16[1] =
   1302 			htons(m->m_pkthdr.rcvif->if_index);
   1303 	if (IN6_IS_ADDR_LINKLOCAL(&t))
   1304 		t.s6_addr16[1] = htons(m->m_pkthdr.rcvif->if_index);
   1305 
   1306 #ifdef COMPAT_RFC1885
   1307 	/*
   1308 	 * xxx guess MTU
   1309 	 * RFC 1885 requires that echo reply should be truncated if it
   1310 	 * does not fit in with (return) path MTU, but the description was
   1311 	 * removed in the new spec.
   1312 	 */
   1313 	if (icmp6_reflect_rt.ro_rt == 0 ||
   1314 	    ! (IN6_ARE_ADDR_EQUAL(&sin6->sin6_addr, &ip6->ip6_dst))) {
   1315 		if (icmp6_reflect_rt.ro_rt) {
   1316 			icmp6_reflect_rt.ro_rt = 0;
   1317 		}
   1318 		bzero(sin6, sizeof(*sin6));
   1319 		sin6->sin6_family = PF_INET6;
   1320 		sin6->sin6_len = sizeof(struct sockaddr_in6);
   1321 		sin6->sin6_addr = ip6->ip6_dst;
   1322 
   1323 		rtalloc((struct route *)&icmp6_reflect_rt.ro_rt);
   1324 	}
   1325 
   1326 	if (icmp6_reflect_rt.ro_rt == 0)
   1327 		goto bad;
   1328 
   1329 	if ((icmp6_reflect_rt.ro_rt->rt_flags & RTF_HOST)
   1330 	    && mtu < icmp6_reflect_rt.ro_rt->rt_ifp->if_mtu)
   1331 		mtu = icmp6_reflect_rt.ro_rt->rt_rmx.rmx_mtu;
   1332 
   1333 	if (mtu < m->m_pkthdr.len) {
   1334 		plen -= (m->m_pkthdr.len - mtu);
   1335 		m_adj(m, mtu - m->m_pkthdr.len);
   1336 	}
   1337 #endif
   1338 	/*
   1339 	 * If the incoming packet was addressed directly to us(i.e. unicast),
   1340 	 * use dst as the src for the reply.
   1341 	 */
   1342 	for (ia = in6_ifaddr; ia; ia = ia->ia_next)
   1343 		if (IN6_ARE_ADDR_EQUAL(&t, &ia->ia_addr.sin6_addr) &&
   1344 		    (ia->ia6_flags & IN6_IFF_ANYCAST) == 0) {
   1345 			src = &t;
   1346 			break;
   1347 		}
   1348 	if (ia == NULL && IN6_IS_ADDR_LINKLOCAL(&t) && (m->m_flags & M_LOOP)) {
   1349 		/*
   1350 		 * This is the case if the dst is our link-local address
   1351 		 * and the sender is also ourseleves.
   1352 		 */
   1353 		src = &t;
   1354 	}
   1355 
   1356 	if (src == 0)
   1357 		/*
   1358 		 * We have not multicast routing yet. So this case matches
   1359 		 * to our multicast, our anycast or not to our unicast.
   1360 		 * Select a source address which has the same scope.
   1361 		 */
   1362 		if ((ia = in6_ifawithscope(m->m_pkthdr.rcvif, &t)) != 0)
   1363 			src = &IA6_SIN6(ia)->sin6_addr;
   1364 
   1365 	if (src == 0)
   1366 		goto bad;
   1367 
   1368 	ip6->ip6_src = *src;
   1369 
   1370 	ip6->ip6_flow = 0;
   1371 	ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
   1372 	ip6->ip6_vfc |= IPV6_VERSION;
   1373 	ip6->ip6_nxt = IPPROTO_ICMPV6;
   1374 	if (m->m_pkthdr.rcvif) {
   1375 		/* XXX: This may not be the outgoing interface */
   1376 		ip6->ip6_hlim = nd_ifinfo[m->m_pkthdr.rcvif->if_index].chlim;
   1377 	}
   1378 
   1379 	icmp6->icmp6_cksum = 0;
   1380 	icmp6->icmp6_cksum = in6_cksum(m, IPPROTO_ICMPV6,
   1381 					sizeof(struct ip6_hdr), plen);
   1382 
   1383 	/*
   1384 	 * xxx option handling
   1385 	 */
   1386 
   1387 	m->m_flags &= ~(M_BCAST|M_MCAST);
   1388 #ifdef IPSEC
   1389 	m->m_pkthdr.rcvif = NULL;
   1390 #endif /*IPSEC*/
   1391 
   1392 #ifdef COMPAT_RFC1885
   1393 	ip6_output(m, NULL, &icmp6_reflect_rt, 0, NULL, &outif);
   1394 #else
   1395 	ip6_output(m, NULL, NULL, 0, NULL, &outif);
   1396 #endif
   1397 	if (outif)
   1398 		icmp6_ifoutstat_inc(outif, type, code);
   1399 
   1400 	return;
   1401 
   1402  bad:
   1403 	m_freem(m);
   1404 	return;
   1405 }
   1406 
   1407 void
   1408 icmp6_fasttimo()
   1409 {
   1410 	mld6_fasttimeo();
   1411 }
   1412 
   1413 static const char *
   1414 icmp6_redirect_diag(src6, dst6, tgt6)
   1415 	struct in6_addr *src6;
   1416 	struct in6_addr *dst6;
   1417 	struct in6_addr *tgt6;
   1418 {
   1419 	static char buf[1024];
   1420 	snprintf(buf, sizeof(buf), "(src=%s dst=%s tgt=%s)",
   1421 		ip6_sprintf(src6), ip6_sprintf(dst6), ip6_sprintf(tgt6));
   1422 	return buf;
   1423 }
   1424 
   1425 void
   1426 icmp6_redirect_input(m, off)
   1427 	register struct mbuf *m;
   1428 	int off;
   1429 {
   1430 	struct ifnet *ifp = m->m_pkthdr.rcvif;
   1431 	struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
   1432 	struct nd_redirect *nd_rd = (struct nd_redirect *)((caddr_t)ip6 + off);
   1433 	int icmp6len = ntohs(ip6->ip6_plen);
   1434 	char *lladdr = NULL;
   1435 	int lladdrlen = 0;
   1436 	u_char *redirhdr = NULL;
   1437 	int redirhdrlen = 0;
   1438 	struct rtentry *rt = NULL;
   1439 	int is_router;
   1440 	int is_onlink;
   1441 	struct in6_addr src6 = ip6->ip6_src;
   1442 	struct in6_addr redtgt6 = nd_rd->nd_rd_target;
   1443 	struct in6_addr reddst6 = nd_rd->nd_rd_dst;
   1444 	union nd_opts ndopts;
   1445 
   1446 	if (!m || !ifp)
   1447 		return;
   1448 
   1449 	/* XXX if we are router, we don't update route by icmp6 redirect */
   1450 	if (ip6_forwarding)
   1451 		return;
   1452 	if (!icmp6_rediraccept)
   1453 		return;
   1454 
   1455 	if (IN6_IS_ADDR_LINKLOCAL(&redtgt6))
   1456 		redtgt6.s6_addr16[1] = htons(ifp->if_index);
   1457 	if (IN6_IS_ADDR_LINKLOCAL(&reddst6))
   1458 		reddst6.s6_addr16[1] = htons(ifp->if_index);
   1459 
   1460 	/* validation */
   1461 	if (!IN6_IS_ADDR_LINKLOCAL(&src6)) {
   1462 		log(LOG_ERR,
   1463 			"ICMP6 redirect sent from %s rejected; "
   1464 			"must be from linklocal\n", ip6_sprintf(&src6));
   1465 		return;
   1466 	}
   1467 	if (ip6->ip6_hlim != 255) {
   1468 		log(LOG_ERR,
   1469 			"ICMP6 redirect sent from %s rejected; "
   1470 			"hlim=%d (must be 255)\n",
   1471 			ip6_sprintf(&src6), ip6->ip6_hlim);
   1472 		return;
   1473 	}
   1474     {
   1475 	/* ip6->ip6_src must be equal to gw for icmp6->icmp6_reddst */
   1476 	struct sockaddr_in6 sin6;
   1477 	struct in6_addr *gw6;
   1478 
   1479 	bzero(&sin6, sizeof(sin6));
   1480 	sin6.sin6_family = AF_INET6;
   1481 	sin6.sin6_len = sizeof(struct sockaddr_in6);
   1482 	bcopy(&reddst6, &sin6.sin6_addr, sizeof(reddst6));
   1483 	rt = rtalloc1((struct sockaddr *)&sin6, 0
   1484 		      );
   1485 	if (rt) {
   1486 		gw6 = &(((struct sockaddr_in6 *)rt->rt_gateway)->sin6_addr);
   1487 		if (bcmp(&src6, gw6, sizeof(struct in6_addr)) != 0) {
   1488 			log(LOG_ERR,
   1489 				"ICMP6 redirect rejected; "
   1490 				"not equal to gw-for-src=%s (must be same): "
   1491 				"%s\n",
   1492 				ip6_sprintf(gw6),
   1493 				icmp6_redirect_diag(&src6, &reddst6, &redtgt6));
   1494 			RTFREE(rt);
   1495 			return;
   1496 		}
   1497 	} else {
   1498 		log(LOG_ERR,
   1499 			"ICMP6 redirect rejected; "
   1500 			"no route found for redirect dst: %s\n",
   1501 			icmp6_redirect_diag(&src6, &reddst6, &redtgt6));
   1502 		return;
   1503 	}
   1504 	RTFREE(rt);
   1505 	rt = NULL;
   1506     }
   1507 	if (IN6_IS_ADDR_MULTICAST(&reddst6)) {
   1508 		log(LOG_ERR,
   1509 			"ICMP6 redirect rejected; "
   1510 			"redirect dst must be unicast: %s\n",
   1511 			icmp6_redirect_diag(&src6, &reddst6, &redtgt6));
   1512 		return;
   1513 	}
   1514 
   1515 	is_router = is_onlink = 0;
   1516 	if (IN6_IS_ADDR_LINKLOCAL(&redtgt6))
   1517 		is_router = 1;	/* router case */
   1518 	if (bcmp(&redtgt6, &reddst6, sizeof(redtgt6)) == 0)
   1519 		is_onlink = 1;	/* on-link destination case */
   1520 	if (!is_router && !is_onlink) {
   1521 		log(LOG_ERR,
   1522 			"ICMP6 redirect rejected; "
   1523 			"neither router case nor onlink case: %s\n",
   1524 			icmp6_redirect_diag(&src6, &reddst6, &redtgt6));
   1525 		return;
   1526 	}
   1527 	/* validation passed */
   1528 
   1529 	icmp6len -= sizeof(*nd_rd);
   1530 	nd6_option_init(nd_rd + 1, icmp6len, &ndopts);
   1531 	if (nd6_options(&ndopts) < 0) {
   1532 		log(LOG_INFO, "icmp6_redirect_input: "
   1533 			"invalid ND option, rejected: %s\n",
   1534 			icmp6_redirect_diag(&src6, &reddst6, &redtgt6));
   1535 		return;
   1536 	}
   1537 
   1538 	if (ndopts.nd_opts_tgt_lladdr) {
   1539 		lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1);
   1540 		lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3;
   1541 	}
   1542 
   1543 	if (ndopts.nd_opts_rh) {
   1544 		redirhdrlen = ndopts.nd_opts_rh->nd_opt_rh_len;
   1545 		redirhdr = (u_char *)(ndopts.nd_opts_rh + 1); /* xxx */
   1546 	}
   1547 
   1548 	if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) {
   1549 		log(LOG_INFO,
   1550 			"icmp6_redirect_input: lladdrlen mismatch for %s "
   1551 			"(if %d, icmp6 packet %d): %s\n",
   1552 			ip6_sprintf(&redtgt6), ifp->if_addrlen, lladdrlen - 2,
   1553 			icmp6_redirect_diag(&src6, &reddst6, &redtgt6));
   1554 	}
   1555 
   1556 	/* RFC 2461 8.3 */
   1557 	nd6_cache_lladdr(ifp, &redtgt6, lladdr, lladdrlen, ND_REDIRECT,
   1558 			 is_onlink ? ND_REDIRECT_ONLINK : ND_REDIRECT_ROUTER);
   1559 
   1560 	if (!is_onlink) {	/* better router case. perform rtredirect. */
   1561 		/* perform rtredirect */
   1562 		struct sockaddr_in6 sdst;
   1563 		struct sockaddr_in6 sgw;
   1564 		struct sockaddr_in6 ssrc;
   1565 
   1566 		bzero(&sdst, sizeof(sdst));
   1567 		bzero(&sgw, sizeof(sgw));
   1568 		bzero(&ssrc, sizeof(ssrc));
   1569 		sdst.sin6_family = sgw.sin6_family = ssrc.sin6_family = AF_INET6;
   1570 		sdst.sin6_len = sgw.sin6_len = ssrc.sin6_len =
   1571 			sizeof(struct sockaddr_in6);
   1572 		bcopy(&redtgt6, &sgw.sin6_addr, sizeof(struct in6_addr));
   1573 		bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr));
   1574 		bcopy(&src6, &ssrc.sin6_addr, sizeof(struct in6_addr));
   1575 		rtredirect((struct sockaddr *)&sdst, (struct sockaddr *)&sgw,
   1576 			   (struct sockaddr *)NULL, RTF_GATEWAY | RTF_HOST,
   1577 			   (struct sockaddr *)&ssrc,
   1578 			   (struct rtentry **)NULL
   1579 			   );
   1580 	}
   1581 	/* finally update cached route in each socket via pfctlinput */
   1582     {
   1583 	struct sockaddr_in6 sdst;
   1584 #if 1
   1585 #else
   1586 	struct ip6protosw *pr;
   1587 #endif
   1588 
   1589 	bzero(&sdst, sizeof(sdst));
   1590 	sdst.sin6_family = AF_INET6;
   1591 	sdst.sin6_len = sizeof(struct sockaddr_in6);
   1592 	bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr));
   1593 #if 1
   1594 	pfctlinput(PRC_REDIRECT_HOST, (struct sockaddr *)&sdst);
   1595 #else
   1596 	/*
   1597 	 * do not use pfctlinput() here, we have different prototype for
   1598 	 * xx_ctlinput() in ip6proto.
   1599 	 */
   1600 	for (pr = (struct ip6protosw *)inet6domain.dom_protosw;
   1601 	     pr < (struct ip6protosw *)inet6domain.dom_protoswNPROTOSW;
   1602 	     pr++) {
   1603 		if (pr->pr_ctlinput) {
   1604 			(*pr->pr_ctlinput)(PRC_REDIRECT_HOST,
   1605 				(struct sockaddr *)&sdst, NULL, NULL, 0);
   1606 		}
   1607 	}
   1608 #endif
   1609 #ifdef IPSEC
   1610 	key_sa_routechange((struct sockaddr *)&sdst);
   1611 #endif
   1612     }
   1613 }
   1614 
   1615 void
   1616 icmp6_redirect_output(m0, rt)
   1617 	struct mbuf *m0;
   1618 	struct rtentry *rt;
   1619 {
   1620 	struct ifnet *ifp;	/* my outgoing interface */
   1621 	struct in6_addr *ifp_ll6;
   1622 	struct in6_addr *router_ll6;
   1623 	struct ip6_hdr *sip6;	/* m0 as struct ip6_hdr */
   1624 	struct mbuf *m = NULL;	/* newly allocated one */
   1625 	struct ip6_hdr *ip6;	/* m as struct ip6_hdr */
   1626 	struct nd_redirect *nd_rd;
   1627 	size_t maxlen;
   1628 	u_char *p;
   1629 	struct ifnet *outif = NULL;
   1630 
   1631 	/* if we are not router, we don't send icmp6 redirect */
   1632 	if (!ip6_forwarding || ip6_accept_rtadv)
   1633 		goto fail;
   1634 
   1635 	/* sanity check */
   1636 	if (!m0 || !rt || !(rt->rt_flags & RTF_UP) || !(ifp = rt->rt_ifp))
   1637 		goto fail;
   1638 
   1639 	/*
   1640 	 * Address check:
   1641 	 *  the source address must identify a neighbor, and
   1642 	 *  the destination address must not be a multicast address
   1643 	 *  [RFC 2461, sec 8.2]
   1644 	 */
   1645 	sip6 = mtod(m0, struct ip6_hdr *);
   1646 	if (nd6_is_addr_neighbor(&sip6->ip6_src, ifp) == 0)
   1647 		goto fail;
   1648 	if (IN6_IS_ADDR_MULTICAST(&sip6->ip6_dst))
   1649 		goto fail;	/* what should we do here? */
   1650 
   1651 	/* rate limit */
   1652 	if (icmp6_ratelimit(&sip6->ip6_src, ND_REDIRECT, 0))
   1653 		goto fail;
   1654 
   1655 	/*
   1656 	 * Since we are going to append up to 1280 bytes (= IPV6_MMTU),
   1657 	 * we almost always ask for an mbuf cluster for simplicity.
   1658 	 * (MHLEN < IPV6_MMTU is almost always true)
   1659 	 */
   1660 	MGETHDR(m, M_DONTWAIT, MT_HEADER);
   1661 	if (!m)
   1662 		goto fail;
   1663 	if (MHLEN < IPV6_MMTU)
   1664 		MCLGET(m, M_DONTWAIT);
   1665 	maxlen = (m->m_flags & M_EXT) ? MCLBYTES : MHLEN;
   1666 	maxlen = min(IPV6_MMTU, maxlen);
   1667 	/* just for safety */
   1668 	if (maxlen < sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr))
   1669 		goto fail;
   1670 
   1671 	{
   1672 		/* get ip6 linklocal address for ifp(my outgoing interface). */
   1673 		struct in6_ifaddr *ia = in6ifa_ifpforlinklocal(ifp);
   1674 		if (ia == NULL)
   1675 			goto fail;
   1676 		ifp_ll6 = &ia->ia_addr.sin6_addr;
   1677 	}
   1678 
   1679 	/* get ip6 linklocal address for the router. */
   1680 	if (rt->rt_gateway && (rt->rt_flags & RTF_GATEWAY)) {
   1681 		struct sockaddr_in6 *sin6;
   1682 		sin6 = (struct sockaddr_in6 *)rt->rt_gateway;
   1683 		router_ll6 = &sin6->sin6_addr;
   1684 		if (!IN6_IS_ADDR_LINKLOCAL(router_ll6))
   1685 			router_ll6 = (struct in6_addr *)NULL;
   1686 	} else
   1687 		router_ll6 = (struct in6_addr *)NULL;
   1688 
   1689 	/* ip6 */
   1690 	ip6 = mtod(m, struct ip6_hdr *);
   1691 	ip6->ip6_flow = 0;
   1692 	ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
   1693 	ip6->ip6_vfc |= IPV6_VERSION;
   1694 	/* ip6->ip6_plen will be set later */
   1695 	ip6->ip6_nxt = IPPROTO_ICMPV6;
   1696 	ip6->ip6_hlim = 255;
   1697 	/* ip6->ip6_src must be linklocal addr for my outgoing if. */
   1698 	bcopy(ifp_ll6, &ip6->ip6_src, sizeof(struct in6_addr));
   1699 	bcopy(&sip6->ip6_src, &ip6->ip6_dst, sizeof(struct in6_addr));
   1700 
   1701 	/* ND Redirect */
   1702 	nd_rd = (struct nd_redirect *)(ip6 + 1);
   1703 	nd_rd->nd_rd_type = ND_REDIRECT;
   1704 	nd_rd->nd_rd_code = 0;
   1705 	nd_rd->nd_rd_reserved = 0;
   1706 	if (rt->rt_flags & RTF_GATEWAY) {
   1707 		/*
   1708 		 * nd_rd->nd_rd_target must be a link-local address in
   1709 		 * better router cases.
   1710 		 */
   1711 		if (!router_ll6)
   1712 			goto fail;
   1713 		bcopy(router_ll6, &nd_rd->nd_rd_target,
   1714 		      sizeof(nd_rd->nd_rd_target));
   1715 		bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst,
   1716 		      sizeof(nd_rd->nd_rd_dst));
   1717 	} else {
   1718 		/* make sure redtgt == reddst */
   1719 		bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_target,
   1720 		      sizeof(nd_rd->nd_rd_target));
   1721 		bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst,
   1722 		      sizeof(nd_rd->nd_rd_dst));
   1723 	}
   1724 
   1725 	p = (u_char *)(nd_rd + 1);
   1726 
   1727 	if (!router_ll6)
   1728 		goto nolladdropt;
   1729 
   1730     {
   1731 	/* target lladdr option */
   1732 	struct rtentry *rt_router = NULL;
   1733 	int len;
   1734 	struct sockaddr_dl *sdl;
   1735 	struct nd_opt_hdr *nd_opt;
   1736 	char *lladdr;
   1737 
   1738 	rt_router = nd6_lookup(router_ll6, 0, ifp);
   1739 	if (!rt_router)
   1740 		goto nolladdropt;
   1741 	if (!(rt_router->rt_flags & RTF_GATEWAY) &&
   1742 	    (rt_router->rt_flags & RTF_LLINFO) &&
   1743 	    (rt_router->rt_gateway->sa_family == AF_LINK) &&
   1744 	    (sdl = (struct sockaddr_dl *)rt_router->rt_gateway) &&
   1745 	    sdl->sdl_alen) {
   1746 		nd_opt = (struct nd_opt_hdr *)p;
   1747 		nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR;
   1748 		len = 2 + ifp->if_addrlen;
   1749 		len = (len + 7) & ~7;	/*round by 8*/
   1750 		nd_opt->nd_opt_len = len >> 3;
   1751 		p += len;
   1752 		lladdr = (char *)(nd_opt + 1);
   1753 		bcopy(LLADDR(sdl), lladdr, ifp->if_addrlen);
   1754 	}
   1755     }
   1756 nolladdropt:;
   1757 
   1758 	m->m_pkthdr.len = m->m_len = p - (u_char *)ip6;
   1759 
   1760 	/* just to be safe */
   1761 #ifdef M_DECRYPTED	/*not openbsd*/
   1762 	if (m0->m_flags & M_DECRYPTED)
   1763 		goto noredhdropt;
   1764 #endif
   1765 
   1766     {
   1767 	/* redirected header option */
   1768 	int len;
   1769 	struct nd_opt_rd_hdr *nd_opt_rh;
   1770 
   1771 	/*
   1772 	 * compute the maximum size for icmp6 redirect header option.
   1773 	 * XXX room for auth header?
   1774 	 */
   1775 	len = maxlen - (p - (u_char *)ip6);
   1776 	len &= ~7;
   1777 
   1778 	/* This is just for simplicity. */
   1779 	if (m0->m_pkthdr.len != m0->m_len) {
   1780 		if (m0->m_next) {
   1781 			m_freem(m0->m_next);
   1782 			m0->m_next = NULL;
   1783 		}
   1784 		m0->m_pkthdr.len = m0->m_len;
   1785 	}
   1786 
   1787 	/*
   1788 	 * Redirected header option spec (RFC2461 4.6.3) talks nothing
   1789 	 * about padding/truncate rule for the original IP packet.
   1790 	 * From the discussion on IPv6imp in Feb 1999, the consensus was:
   1791 	 * - "attach as much as possible" is the goal
   1792 	 * - pad if not aligned (original size can be guessed by original
   1793 	 *   ip6 header)
   1794 	 * Following code adds the padding if it is simple enough,
   1795 	 * and truncates if not.
   1796 	 */
   1797 	if (m0->m_next || m0->m_pkthdr.len != m0->m_len)
   1798 		panic("assumption failed in %s:%d\n", __FILE__, __LINE__);
   1799 
   1800 	if (len - sizeof(*nd_opt_rh) < m0->m_pkthdr.len) {
   1801 		/* not enough room, truncate */
   1802 		m0->m_pkthdr.len = m0->m_len = len - sizeof(*nd_opt_rh);
   1803 	} else {
   1804 		/* enough room, pad or truncate */
   1805 		size_t extra;
   1806 
   1807 		extra = m0->m_pkthdr.len % 8;
   1808 		if (extra) {
   1809 			/* pad if easy enough, truncate if not */
   1810 			if (8 - extra <= M_TRAILINGSPACE(m0)) {
   1811 				/* pad */
   1812 				m0->m_len += (8 - extra);
   1813 				m0->m_pkthdr.len += (8 - extra);
   1814 			} else {
   1815 				/* truncate */
   1816 				m0->m_pkthdr.len -= extra;
   1817 				m0->m_len -= extra;
   1818 			}
   1819 		}
   1820 		len = m0->m_pkthdr.len + sizeof(*nd_opt_rh);
   1821 		m0->m_pkthdr.len = m0->m_len = len - sizeof(*nd_opt_rh);
   1822 	}
   1823 
   1824 	nd_opt_rh = (struct nd_opt_rd_hdr *)p;
   1825 	bzero(nd_opt_rh, sizeof(*nd_opt_rh));
   1826 	nd_opt_rh->nd_opt_rh_type = ND_OPT_REDIRECTED_HEADER;
   1827 	nd_opt_rh->nd_opt_rh_len = len >> 3;
   1828 	p += sizeof(*nd_opt_rh);
   1829 	m->m_pkthdr.len = m->m_len = p - (u_char *)ip6;
   1830 
   1831 	/* connect m0 to m */
   1832 	m->m_next = m0;
   1833 	m->m_pkthdr.len = m->m_len + m0->m_len;
   1834     }
   1835 #ifdef M_DECRYPTED	/*not openbsd*/
   1836 noredhdropt:;
   1837 #endif
   1838 
   1839 	if (IN6_IS_ADDR_LINKLOCAL(&sip6->ip6_src))
   1840 		sip6->ip6_src.s6_addr16[1] = 0;
   1841 	if (IN6_IS_ADDR_LINKLOCAL(&sip6->ip6_dst))
   1842 		sip6->ip6_dst.s6_addr16[1] = 0;
   1843 #if 0
   1844 	if (IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_src))
   1845 		ip6->ip6_src.s6_addr16[1] = 0;
   1846 	if (IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_dst))
   1847 		ip6->ip6_dst.s6_addr16[1] = 0;
   1848 #endif
   1849 	if (IN6_IS_ADDR_LINKLOCAL(&nd_rd->nd_rd_target))
   1850 		nd_rd->nd_rd_target.s6_addr16[1] = 0;
   1851 	if (IN6_IS_ADDR_LINKLOCAL(&nd_rd->nd_rd_dst))
   1852 		nd_rd->nd_rd_dst.s6_addr16[1] = 0;
   1853 
   1854 	ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr));
   1855 
   1856 	nd_rd->nd_rd_cksum = 0;
   1857 	nd_rd->nd_rd_cksum
   1858 		= in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), ntohs(ip6->ip6_plen));
   1859 
   1860 	/* send the packet to outside... */
   1861 #ifdef IPSEC
   1862 	m->m_pkthdr.rcvif = NULL;
   1863 #endif /*IPSEC*/
   1864 	ip6_output(m, NULL, NULL, 0, NULL, &outif);
   1865 	if (outif) {
   1866 		icmp6_ifstat_inc(outif, ifs6_out_msg);
   1867 		icmp6_ifstat_inc(outif, ifs6_out_redirect);
   1868 	}
   1869 	icmp6stat.icp6s_outhist[ND_REDIRECT]++;
   1870 
   1871 	return;
   1872 
   1873 fail:
   1874 	if (m)
   1875 		m_freem(m);
   1876 	if (m0)
   1877 		m_freem(m0);
   1878 }
   1879 
   1880 /*
   1881  * ICMPv6 socket option processing.
   1882  */
   1883 int
   1884 icmp6_ctloutput(op, so, level, optname, mp)
   1885 	int op;
   1886 	struct socket *so;
   1887 	int level, optname;
   1888 	struct mbuf **mp;
   1889 {
   1890 	register struct in6pcb *in6p = sotoin6pcb(so);
   1891 	register struct mbuf *m = *mp;
   1892 	int error = 0;
   1893 
   1894 	if (level != IPPROTO_ICMPV6) {
   1895 		error = EINVAL;
   1896 		if (op == PRCO_SETOPT && m)
   1897 			(void)m_free(m);
   1898 	} else switch(op) {
   1899 	 case PRCO_SETOPT:
   1900 		 switch (optname) {
   1901 		  case ICMP6_FILTER:
   1902 		  {
   1903 			  struct icmp6_filter *p;
   1904 
   1905 			  p = mtod(m, struct icmp6_filter *);
   1906 			  if (!p || !in6p->in6p_icmp6filt) {
   1907 				  error = EINVAL;
   1908 				  break;
   1909 			  }
   1910 			  bcopy(p, in6p->in6p_icmp6filt,
   1911 				sizeof(struct icmp6_filter));
   1912 			  error = 0;
   1913 			  break;
   1914 		  }
   1915 
   1916 		  default:
   1917 			  error = ENOPROTOOPT;
   1918 			  break;
   1919 		 }
   1920 		 if (m)
   1921 			 (void)m_free(m);
   1922 		 break;
   1923 
   1924 	 case PRCO_GETOPT:
   1925 		 switch (optname) {
   1926 		  case ICMP6_FILTER:
   1927 		  {
   1928 			  struct icmp6_filter *p;
   1929 
   1930 			  if (!in6p->in6p_icmp6filt) {
   1931 				  error = EINVAL;
   1932 				  break;
   1933 			  }
   1934 			  *mp = m = m_get(M_WAIT, MT_SOOPTS);
   1935 			  m->m_len = sizeof(struct icmp6_filter);
   1936 			  p = mtod(m, struct icmp6_filter *);
   1937 			  bcopy(in6p->in6p_icmp6filt, p,
   1938 				sizeof(struct icmp6_filter));
   1939 			  error = 0;
   1940 			  break;
   1941 		  }
   1942 
   1943 		  default:
   1944 			  error = ENOPROTOOPT;
   1945 			  break;
   1946 		 }
   1947 		 break;
   1948 	}
   1949 
   1950 	return(error);
   1951 }
   1952 
   1953 /*
   1954  * Perform rate limit check.
   1955  * Returns 0 if it is okay to send the icmp6 packet.
   1956  * Returns 1 if the router SHOULD NOT send this icmp6 packet due to rate
   1957  * limitation.
   1958  *
   1959  * XXX per-destination/type check necessary?
   1960  */
   1961 static int
   1962 icmp6_ratelimit(dst, type, code)
   1963 	const struct in6_addr *dst;	/* not used at this moment */
   1964 	const int type;			/* not used at this moment */
   1965 	const int code;			/* not used at this moment */
   1966 {
   1967 	static struct timeval icmp6errratelim_last;
   1968 
   1969 	/*
   1970 	 * ratecheck() returns true if it is okay to send.  We return
   1971 	 * true if it is not okay to send.
   1972 	 */
   1973 	return (ratecheck(&icmp6errratelim_last, &icmp6errratelim) == 0);
   1974 }
   1975 
   1976 static struct rtentry *
   1977 icmp6_mtudisc_clone(dst)
   1978 	struct sockaddr *dst;
   1979 {
   1980 	struct rtentry *rt;
   1981 	int    error;
   1982 
   1983 	rt = rtalloc1(dst, 1);
   1984 	if (rt == 0)
   1985 		return NULL;
   1986 
   1987 	/* If we didn't get a host route, allocate one */
   1988 	if ((rt->rt_flags & RTF_HOST) == 0) {
   1989 		struct rtentry *nrt;
   1990 
   1991 		error = rtrequest((int) RTM_ADD, dst,
   1992 		    (struct sockaddr *) rt->rt_gateway,
   1993 		    (struct sockaddr *) 0,
   1994 		    RTF_GATEWAY | RTF_HOST | RTF_DYNAMIC, &nrt);
   1995 		if (error) {
   1996 			rtfree(rt);
   1997 			rtfree(nrt);
   1998 			return NULL;
   1999 		}
   2000 		nrt->rt_rmx = rt->rt_rmx;
   2001 		rtfree(rt);
   2002 		rt = nrt;
   2003 	}
   2004 	error = rt_timer_add(rt, icmp6_mtudisc_timeout,
   2005 			icmp6_mtudisc_timeout_q);
   2006 	if (error) {
   2007 		rtfree(rt);
   2008 		return NULL;
   2009 	}
   2010 
   2011 	return rt;	/* caller need to call rtfree() */
   2012 }
   2013 
   2014 static void
   2015 icmp6_mtudisc_timeout(rt, r)
   2016 	struct rtentry *rt;
   2017 	struct rttimer *r;
   2018 {
   2019 	if (rt == NULL)
   2020 		panic("icmp6_mtudisc_timeout: bad route to timeout");
   2021 	if ((rt->rt_flags & (RTF_DYNAMIC | RTF_HOST)) ==
   2022 	    (RTF_DYNAMIC | RTF_HOST)) {
   2023 		rtrequest((int) RTM_DELETE, (struct sockaddr *)rt_key(rt),
   2024 		    rt->rt_gateway, rt_mask(rt), rt->rt_flags, 0);
   2025 	} else {
   2026 		if ((rt->rt_rmx.rmx_locks & RTV_MTU) == 0) {
   2027 			rt->rt_rmx.rmx_mtu = 0;
   2028 		}
   2029 	}
   2030 }
   2031 
   2032 #include <vm/vm.h>
   2033 #include <sys/sysctl.h>
   2034 int
   2035 icmp6_sysctl(name, namelen, oldp, oldlenp, newp, newlen)
   2036 	int *name;
   2037 	u_int namelen;
   2038 	void *oldp;
   2039 	size_t *oldlenp;
   2040 	void *newp;
   2041 	size_t newlen;
   2042 {
   2043 
   2044 	/* All sysctl names at this level are terminal. */
   2045 	if (namelen != 1)
   2046 		return ENOTDIR;
   2047 
   2048 	switch (name[0]) {
   2049 
   2050 	case ICMPV6CTL_REDIRACCEPT:
   2051 		return sysctl_int(oldp, oldlenp, newp, newlen,
   2052 				&icmp6_rediraccept);
   2053 	case ICMPV6CTL_REDIRTIMEOUT:
   2054 		return sysctl_int(oldp, oldlenp, newp, newlen,
   2055 				&icmp6_redirtimeout);
   2056 	case ICMPV6CTL_STATS:
   2057 		return sysctl_rdstruct(oldp, oldlenp, newp,
   2058 				&icmp6stat, sizeof(icmp6stat));
   2059 	case ICMPV6CTL_ERRRATELIMIT:
   2060 	    {
   2061 		int rate_usec, error, s;
   2062 
   2063 		/*
   2064 		 * The sysctl specifies the rate in usec-between-icmp,
   2065 		 * so we must convert from/to a timeval.
   2066 		 */
   2067 		rate_usec = (icmp6errratelim.tv_sec * 1000000) +
   2068 		    icmp6errratelim.tv_usec;
   2069 		error = sysctl_int(oldp, oldlenp, newp, newlen, &rate_usec);
   2070 		if (error)
   2071 			return (error);
   2072 		s = splsoftnet();
   2073 		icmp6errratelim.tv_sec = rate_usec / 1000000;
   2074 		icmp6errratelim.tv_usec = rate_usec % 1000000;
   2075 		splx(s);
   2076 
   2077 		return (0);
   2078 	    }
   2079 	case ICMPV6CTL_ND6_PRUNE:
   2080 		return sysctl_int(oldp, oldlenp, newp, newlen, &nd6_prune);
   2081 	case ICMPV6CTL_ND6_DELAY:
   2082 		return sysctl_int(oldp, oldlenp, newp, newlen, &nd6_delay);
   2083 	case ICMPV6CTL_ND6_UMAXTRIES:
   2084 		return sysctl_int(oldp, oldlenp, newp, newlen, &nd6_umaxtries);
   2085 	case ICMPV6CTL_ND6_MMAXTRIES:
   2086 		return sysctl_int(oldp, oldlenp, newp, newlen, &nd6_mmaxtries);
   2087 	case ICMPV6CTL_ND6_USELOOPBACK:
   2088 		return sysctl_int(oldp, oldlenp, newp, newlen,
   2089 				&nd6_useloopback);
   2090 	case ICMPV6CTL_ND6_PROXYALL:
   2091 		return sysctl_int(oldp, oldlenp, newp, newlen, &nd6_proxyall);
   2092 	case ICMPV6CTL_NODEINFO:
   2093 		return sysctl_int(oldp, oldlenp, newp, newlen, &icmp6_nodeinfo);
   2094 	default:
   2095 		return ENOPROTOOPT;
   2096 	}
   2097 	/* NOTREACHED */
   2098 }
   2099