Home | History | Annotate | Line # | Download | only in netinet6
icmp6.c revision 1.18
      1 /*	$NetBSD: icmp6.c,v 1.18 2000/01/16 18:06:03 itojun 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 <netinet6/ip6.h>
     90 #include <netinet6/ip6_var.h>
     91 #include <netinet6/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 extern struct ip6protosw inet6sw[];
    111 extern u_char ip6_protox[];
    112 
    113 struct icmp6stat icmp6stat;
    114 
    115 extern struct in6pcb rawin6pcb;
    116 extern u_int icmp6errratelim;
    117 extern int icmp6_nodeinfo;
    118 static struct rttimer_queue *icmp6_mtudisc_timeout_q = NULL;
    119 extern int pmtu_expire;
    120 
    121 static int icmp6_rip6_input __P((struct mbuf **, int));
    122 static int icmp6_ratelimit __P((const struct in6_addr *, const int, const int));
    123 static const char *icmp6_redirect_diag __P((struct in6_addr *,
    124 	struct in6_addr *, struct in6_addr *));
    125 static struct mbuf * ni6_input __P((struct mbuf *, int));
    126 static int ni6_addrs __P((struct icmp6_nodeinfo *, struct mbuf *,
    127 			  struct ifnet **));
    128 static int ni6_store_addrs __P((struct icmp6_nodeinfo *, struct icmp6_nodeinfo *,
    129 				struct ifnet *, int));
    130 static struct rtentry *icmp6_mtudisc_clone __P((struct sockaddr *));
    131 static void icmp6_mtudisc_timeout __P((struct rtentry *, struct rttimer *));
    132 
    133 #ifdef COMPAT_RFC1885
    134 static struct route_in6 icmp6_reflect_rt;
    135 #endif
    136 static struct timeval icmp6_nextsend = {0, 0};
    137 
    138 void
    139 icmp6_init()
    140 {
    141 	mld6_init();
    142 	icmp6_mtudisc_timeout_q = rt_timer_queue_create(pmtu_expire);
    143 }
    144 
    145 /*
    146  * Generate an error packet of type error in response to bad IP6 packet.
    147  */
    148 void
    149 icmp6_error(m, type, code, param)
    150 	struct mbuf *m;
    151 	int type, code, param;
    152 {
    153 	struct ip6_hdr *oip6, *nip6;
    154 	struct icmp6_hdr *icmp6;
    155 	u_int preplen;
    156 	int off;
    157 	u_char nxt;
    158 
    159 	icmp6stat.icp6s_error++;
    160 
    161 #ifdef M_DECRYPTED	/*not openbsd*/
    162 	if (m->m_flags & M_DECRYPTED)
    163 		goto freeit;
    164 #endif
    165 
    166 #ifndef PULLDOWN_TEST
    167 	IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), );
    168 #else
    169 	if (m->m_len < sizeof(struct ip6_hdr)) {
    170 		m = m_pullup(m, sizeof(struct ip6_hdr));
    171 		if (m == NULL)
    172 			return;
    173 	}
    174 #endif
    175 	oip6 = mtod(m, struct ip6_hdr *);
    176 
    177 	/*
    178 	 * Multicast destination check. For unrecognized option errors,
    179 	 * this check has already done in ip6_unknown_opt(), so we can
    180 	 * check only for other errors.
    181 	 */
    182 	if ((m->m_flags & (M_BCAST|M_MCAST) ||
    183 	     IN6_IS_ADDR_MULTICAST(&oip6->ip6_dst)) &&
    184 	    (type != ICMP6_PACKET_TOO_BIG &&
    185 	     (type != ICMP6_PARAM_PROB ||
    186 	      code != ICMP6_PARAMPROB_OPTION)))
    187 		goto freeit;
    188 
    189 	/* Source address check. XXX: the case of anycast source? */
    190 	if (IN6_IS_ADDR_UNSPECIFIED(&oip6->ip6_src) ||
    191 	    IN6_IS_ADDR_MULTICAST(&oip6->ip6_src))
    192 		goto freeit;
    193 
    194 	/*
    195 	 * If the erroneous packet is also an ICMP error, discard it.
    196 	 */
    197 	off = sizeof(struct ip6_hdr);
    198 	nxt = oip6->ip6_nxt;
    199 	while (1) {		/* XXX: should avoid inf. loop explicitly? */
    200 		struct ip6_ext *ip6e;
    201 		struct icmp6_hdr *icp;
    202 
    203 		switch(nxt) {
    204 		case IPPROTO_IPV6:
    205 		case IPPROTO_IPV4:
    206 		case IPPROTO_UDP:
    207 		case IPPROTO_TCP:
    208 		case IPPROTO_ESP:
    209 		case IPPROTO_IPCOMP:
    210 		case IPPROTO_FRAGMENT:
    211 			/*
    212 			 * ICMPv6 error must not be fragmented.
    213 			 * XXX: but can we trust the sender?
    214 			 */
    215 		default:
    216 			/* What if unknown header followed by ICMP error? */
    217 			goto generate;
    218 		case IPPROTO_ICMPV6:
    219 #ifndef PULLDOWN_TEST
    220 			IP6_EXTHDR_CHECK(m, 0, off + sizeof(struct icmp6_hdr), );
    221 			icp = (struct icmp6_hdr *)(mtod(m, caddr_t) + off);
    222 #else
    223 			IP6_EXTHDR_GET(icp, struct icmp6_hdr *, m, off,
    224 				sizeof(*icp));
    225 			if (icp == NULL) {
    226 				icmp6stat.icp6s_tooshort++;
    227 				return;
    228 			}
    229 #endif
    230 			if (icp->icmp6_type < ICMP6_ECHO_REQUEST
    231 			 || icp->icmp6_type == ND_REDIRECT) {
    232 				/*
    233 				 * ICMPv6 error
    234 				 * Special case: for redirect (which is
    235 				 * informational) we must not send icmp6 error.
    236 				 */
    237 				icmp6stat.icp6s_canterror++;
    238 				goto freeit;
    239 			} else {
    240 				/* ICMPv6 informational */
    241 				goto generate;
    242 			}
    243 		case IPPROTO_HOPOPTS:
    244 		case IPPROTO_DSTOPTS:
    245 		case IPPROTO_ROUTING:
    246 		case IPPROTO_AH:
    247 #ifndef PULLDOWN_TEST
    248 			IP6_EXTHDR_CHECK(m, 0, off + sizeof(struct ip6_ext), );
    249 			ip6e = (struct ip6_ext *)(mtod(m, caddr_t) + off);
    250 #else
    251 			IP6_EXTHDR_GET(ip6e, struct ip6_ext *, m, off,
    252 				sizeof(*ip6e));
    253 			if (ip6e == NULL) {
    254 				/*XXX stat */
    255 				return;
    256 			}
    257 #endif
    258 			if (nxt == IPPROTO_AH)
    259 				off += (ip6e->ip6e_len + 2) << 2;
    260 			else
    261 				off += (ip6e->ip6e_len + 1) << 3;
    262 			nxt = ip6e->ip6e_nxt;
    263 			break;
    264 		}
    265 	}
    266 
    267   freeit:
    268 	/*
    269 	 * If we can't tell wheter or not we can generate ICMP6, free it.
    270 	 */
    271 	m_freem(m);
    272 	return;
    273 
    274   generate:
    275 	oip6 = mtod(m, struct ip6_hdr *); /* adjust pointer */
    276 
    277 	/* Finally, do rate limitation check. */
    278 	if (icmp6_ratelimit(&oip6->ip6_src, type, code)) {
    279 		icmp6stat.icp6s_toofreq++;
    280 		goto freeit;
    281 	}
    282 
    283 	/*
    284 	 * OK, ICMP6 can be generated.
    285 	 */
    286 
    287 	if (m->m_pkthdr.len >= ICMPV6_PLD_MAXLEN)
    288 		m_adj(m, ICMPV6_PLD_MAXLEN - m->m_pkthdr.len);
    289 
    290 	preplen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr);
    291 	M_PREPEND(m, preplen, M_DONTWAIT);
    292 	if (m && m->m_len < preplen)
    293 		m = m_pullup(m, preplen);
    294 	if (m == NULL) {
    295 		printf("ENOBUFS in icmp6_error %d\n", __LINE__);
    296 		return;
    297 	}
    298 
    299 	nip6 = mtod(m, struct ip6_hdr *);
    300 	nip6->ip6_src  = oip6->ip6_src;
    301 	nip6->ip6_dst  = oip6->ip6_dst;
    302 
    303 	if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_src))
    304 		oip6->ip6_src.s6_addr16[1] = 0;
    305 	if (IN6_IS_SCOPE_LINKLOCAL(&oip6->ip6_dst))
    306 		oip6->ip6_dst.s6_addr16[1] = 0;
    307 
    308 	icmp6 = (struct icmp6_hdr *)(nip6 + 1);
    309 	icmp6->icmp6_type = type;
    310 	icmp6->icmp6_code = code;
    311 	icmp6->icmp6_pptr = htonl((u_int32_t)param);
    312 
    313 	icmp6stat.icp6s_outhist[type]++;
    314 	icmp6_reflect(m, sizeof(struct ip6_hdr)); /*header order: IPv6 - ICMPv6*/
    315 }
    316 
    317 /*
    318  * Process a received ICMP6 message.
    319  */
    320 int
    321 icmp6_input(mp, offp, proto)
    322 	struct mbuf **mp;
    323 	int *offp, proto;
    324 {
    325 	struct mbuf *m = *mp, *n;
    326 	struct ip6_hdr *ip6, *nip6;
    327 	struct icmp6_hdr *icmp6, *nicmp6;
    328 	int off = *offp;
    329 	int icmp6len = m->m_pkthdr.len - *offp;
    330 	int code, sum, noff;
    331 	struct sockaddr_in6 icmp6src;
    332 
    333 #ifndef PULLDOWN_TEST
    334 	IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_hdr), IPPROTO_DONE);
    335 	/* m might change if M_LOOP. So, call mtod after this */
    336 #endif
    337 
    338 	/*
    339 	 * Locate icmp6 structure in mbuf, and check
    340 	 * that not corrupted and of at least minimum length
    341 	 */
    342 
    343 	ip6 = mtod(m, struct ip6_hdr *);
    344 	if (icmp6len < sizeof(struct icmp6_hdr)) {
    345 		icmp6stat.icp6s_tooshort++;
    346 		goto freeit;
    347 	}
    348 
    349 	/*
    350 	 * calculate the checksum
    351 	 */
    352 #ifndef PULLDOWN_TEST
    353 	icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off);
    354 #else
    355 	IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off, sizeof(*icmp6));
    356 	if (icmp6 == NULL) {
    357 		icmp6stat.icp6s_tooshort++;
    358 		return IPPROTO_DONE;
    359 	}
    360 #endif
    361 	code = icmp6->icmp6_code;
    362 
    363 	if ((sum = in6_cksum(m, IPPROTO_ICMPV6, off, icmp6len)) != 0) {
    364 		log(LOG_ERR,
    365 		    "ICMP6 checksum error(%d|%x) %s\n",
    366 		    icmp6->icmp6_type,
    367 		    sum,
    368 		    ip6_sprintf(&ip6->ip6_src));
    369 		icmp6stat.icp6s_checksum++;
    370 		goto freeit;
    371 	}
    372 
    373 #if defined(NFAITH) && 0 < NFAITH
    374 	if (m->m_pkthdr.rcvif && m->m_pkthdr.rcvif->if_type == IFT_FAITH) {
    375 		/*
    376 		 * Deliver very specific ICMP6 type only.
    377 		 * This is important to deilver TOOBIG.  Otherwise PMTUD
    378 		 * will not work.
    379 		 */
    380 		switch (icmp6->icmp6_type) {
    381 		case ICMP6_DST_UNREACH:
    382 		case ICMP6_PACKET_TOO_BIG:
    383 		case ICMP6_TIME_EXCEEDED:
    384 			break;
    385 		default:
    386 			goto freeit;
    387 		}
    388 	}
    389 #endif
    390 
    391 #ifdef IPSEC
    392 	/* drop it if it does not match the default policy */
    393 	if (ipsec6_in_reject(m, NULL)) {
    394 		ipsecstat.in_polvio++;
    395 		goto freeit;
    396 	}
    397 #endif
    398 
    399 	icmp6stat.icp6s_inhist[icmp6->icmp6_type]++;
    400 	icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_msg);
    401 	if (icmp6->icmp6_type < ICMP6_INFOMSG_MASK)
    402 		icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_error);
    403 
    404 	switch (icmp6->icmp6_type) {
    405 
    406 	case ICMP6_DST_UNREACH:
    407 		icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_dstunreach);
    408 		switch (code) {
    409 		case ICMP6_DST_UNREACH_NOROUTE:
    410 			code = PRC_UNREACH_NET;
    411 			break;
    412 		case ICMP6_DST_UNREACH_ADMIN:
    413 			icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_adminprohib);
    414 		case ICMP6_DST_UNREACH_ADDR:
    415 			code = PRC_UNREACH_HOST;
    416 			break;
    417 		case ICMP6_DST_UNREACH_NOTNEIGHBOR:
    418 			code = PRC_UNREACH_SRCFAIL;
    419 			break;
    420 		case ICMP6_DST_UNREACH_NOPORT:
    421 			code = PRC_UNREACH_PORT;
    422 			break;
    423 		default:
    424 			goto badcode;
    425 		}
    426 		goto deliver;
    427 		break;
    428 
    429 	case ICMP6_PACKET_TOO_BIG:
    430 		icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_pkttoobig);
    431 		if (code != 0)
    432 			goto badcode;
    433 	    {
    434 		u_int mtu = ntohl(icmp6->icmp6_mtu);
    435 		struct rtentry *rt = NULL;
    436 		struct sockaddr_in6 sin6;
    437 
    438 		if (icmp6len < sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr)) {
    439 			icmp6stat.icp6s_tooshort++;
    440 			goto freeit;
    441 		}
    442 #ifndef PULLDOWN_TEST
    443 		IP6_EXTHDR_CHECK(m, off,
    444 			sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr),
    445 			IPPROTO_DONE);
    446 		icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off);
    447 #else
    448 		IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off,
    449 			sizeof(*icmp6) + sizeof(struct ip6_hdr));
    450 		if (icmp6 == NULL) {
    451 			icmp6stat.icp6s_tooshort++;
    452 			return IPPROTO_DONE;
    453 		}
    454 #endif
    455 		code = PRC_MSGSIZE;
    456 		bzero(&sin6, sizeof(sin6));
    457 		sin6.sin6_family = PF_INET6;
    458 		sin6.sin6_len = sizeof(struct sockaddr_in6);
    459 		sin6.sin6_addr = ((struct ip6_hdr *)(icmp6 + 1))->ip6_dst;
    460 		rt = rtalloc1((struct sockaddr *)&sin6, 1);	/*clone*/
    461 		if (!rt || (rt->rt_flags & RTF_HOST) == 0) {
    462 			if (rt)
    463 				RTFREE(rt);
    464 			rt = icmp6_mtudisc_clone((struct sockaddr *)&sin6);
    465 		}
    466 
    467 		if (rt && (rt->rt_flags & RTF_HOST)
    468 		    && !(rt->rt_rmx.rmx_locks & RTV_MTU)) {
    469 			if (mtu < IPV6_MMTU) {
    470 				/* xxx */
    471 				rt->rt_rmx.rmx_locks |= RTV_MTU;
    472 			} else if (mtu < rt->rt_ifp->if_mtu &&
    473 				   rt->rt_rmx.rmx_mtu > mtu) {
    474 				rt->rt_rmx.rmx_mtu = mtu;
    475 			}
    476 		}
    477 		if (rt)
    478 			RTFREE(rt);
    479 
    480 		goto deliver;
    481 	    }
    482 		break;
    483 
    484 	case ICMP6_TIME_EXCEEDED:
    485 		icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_timeexceed);
    486 		switch (code) {
    487 		case ICMP6_TIME_EXCEED_TRANSIT:
    488 		case ICMP6_TIME_EXCEED_REASSEMBLY:
    489 			code += PRC_TIMXCEED_INTRANS;
    490 			break;
    491 		default:
    492 			goto badcode;
    493 		}
    494 		goto deliver;
    495 		break;
    496 
    497 	case ICMP6_PARAM_PROB:
    498 		icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_paramprob);
    499 		switch (code) {
    500 		case ICMP6_PARAMPROB_NEXTHEADER:
    501 			code = PRC_UNREACH_PROTOCOL;
    502 			break;
    503 		case ICMP6_PARAMPROB_HEADER:
    504 		case ICMP6_PARAMPROB_OPTION:
    505 			code = PRC_PARAMPROB;
    506 			break;
    507 		default:
    508 			goto badcode;
    509 		}
    510 		goto deliver;
    511 		break;
    512 
    513 	case ICMP6_ECHO_REQUEST:
    514 		icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echo);
    515 		if (code != 0)
    516 			goto badcode;
    517 		if ((n = m_copy(m, 0, M_COPYALL)) == NULL) {
    518 			/* Give up remote */
    519 			break;
    520 		}
    521 		if ((n->m_flags & M_EXT) != 0
    522 		 || n->m_len < off + sizeof(struct icmp6_hdr)) {
    523 			struct mbuf *n0 = n;
    524 
    525 			/*
    526 			 * Prepare an internal mbuf. m_pullup() doesn't
    527 			 * always copy the length we specified.
    528 			 */
    529 			MGETHDR(n, M_DONTWAIT, n0->m_type);
    530 			if (n == NULL) {
    531 				/* Give up remote */
    532 				m_freem(n0);
    533 				break;
    534 			}
    535 			M_COPY_PKTHDR(n, n0);
    536 			/*
    537 			 * Copy IPv6 and ICMPv6 only.
    538 			 */
    539 			nip6 = mtod(n, struct ip6_hdr *);
    540 			bcopy(ip6, nip6, sizeof(struct ip6_hdr));
    541 			nicmp6 = (struct icmp6_hdr *)(nip6 + 1);
    542 			bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr));
    543 			noff = sizeof(struct ip6_hdr);
    544 			n->m_pkthdr.len = n->m_len =
    545 				noff + sizeof(struct icmp6_hdr);
    546 			/*
    547 			 * Adjust mbuf. ip6_plen will be adjusted in
    548 			 * ip6_output().
    549 			 */
    550 			m_adj(n0, off + sizeof(struct icmp6_hdr));
    551 			n->m_pkthdr.len += n0->m_pkthdr.len;
    552 			n->m_next = n0;
    553 			n0->m_flags &= ~M_PKTHDR;
    554 		} else {
    555 			nip6 = mtod(n, struct ip6_hdr *);
    556 			nicmp6 = (struct icmp6_hdr *)((caddr_t)nip6 + off);
    557 			noff = off;
    558 		}
    559 		nicmp6->icmp6_type = ICMP6_ECHO_REPLY;
    560 		nicmp6->icmp6_code = 0;
    561 		if (n) {
    562 			icmp6stat.icp6s_reflect++;
    563 			icmp6stat.icp6s_outhist[ICMP6_ECHO_REPLY]++;
    564 			icmp6_reflect(n, noff);
    565 		}
    566 		break;
    567 
    568 	case ICMP6_ECHO_REPLY:
    569 		icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_echoreply);
    570 		if (code != 0)
    571 			goto badcode;
    572 		break;
    573 
    574 	case MLD6_LISTENER_QUERY:
    575 	case MLD6_LISTENER_REPORT:
    576 		if (icmp6len < sizeof(struct mld6_hdr))
    577 			goto badlen;
    578 		if (icmp6->icmp6_type == MLD6_LISTENER_QUERY) /* XXX: ugly... */
    579 			icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldquery);
    580 		else
    581 			icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mldreport);
    582 		IP6_EXTHDR_CHECK(m, off, icmp6len, IPPROTO_DONE);
    583 		mld6_input(m, off);
    584 		/* m stays. */
    585 		break;
    586 
    587 	case MLD6_LISTENER_DONE:
    588 		icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_mlddone);
    589 		if (icmp6len < sizeof(struct mld6_hdr))	/* necessary? */
    590 			goto badlen;
    591 		break;		/* nothing to be done in kernel */
    592 
    593 	case MLD6_MTRACE_RESP:
    594 	case MLD6_MTRACE:
    595 		/* XXX: these two are experimental. not officially defind. */
    596 		/* XXX: per-interface statistics? */
    597 		break;		/* just pass it to the userland daemon */
    598 
    599 	case ICMP6_WRUREQUEST:	/* ICMP6_FQDN_QUERY */
    600 	    {
    601 		enum { WRU, FQDN } mode;
    602 
    603 		if (code != 0)
    604 			goto badcode;
    605 		if (!icmp6_nodeinfo)
    606 			break;
    607 
    608 		if (icmp6len == sizeof(struct icmp6_hdr) + 4)
    609 			mode = WRU;
    610 		else if (icmp6len >= sizeof(struct icmp6_hdr) + 8) /* XXX */
    611 			mode = FQDN;
    612 		else
    613 			goto badlen;
    614 
    615 		if (mode == FQDN) {
    616 #ifndef PULLDOWN_TEST
    617 			IP6_EXTHDR_CHECK(m, off, sizeof(struct icmp6_nodeinfo),
    618 					 IPPROTO_DONE);
    619 #endif
    620 			n = m_copy(m, 0, M_COPYALL);
    621 			if (n)
    622 				n = ni6_input(n, off);
    623 			if (n)
    624 				noff = sizeof(struct ip6_hdr);
    625 		} else {
    626 			u_char *p;
    627 
    628 			MGETHDR(n, M_DONTWAIT, m->m_type);
    629 			if (n == NULL) {
    630 				/* Give up remote */
    631 				break;
    632 			}
    633 			/*
    634 			 * Copy IPv6 and ICMPv6 only.
    635 			 */
    636 			nip6 = mtod(n, struct ip6_hdr *);
    637 			bcopy(ip6, nip6, sizeof(struct ip6_hdr));
    638 			nicmp6 = (struct icmp6_hdr *)(nip6 + 1);
    639 			bcopy(icmp6, nicmp6, sizeof(struct icmp6_hdr));
    640 			p = (u_char *)(nicmp6 + 1);
    641 			bzero(p, 4);
    642 			bcopy(hostname, p + 4, hostnamelen);
    643 			noff = sizeof(struct ip6_hdr);
    644 			M_COPY_PKTHDR(n, m); /* just for recvif */
    645 			n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) +
    646 				sizeof(struct icmp6_hdr) + 4 + hostnamelen;
    647 			nicmp6->icmp6_type = ICMP6_WRUREPLY;
    648 			nicmp6->icmp6_code = 0;
    649 		}
    650 #undef hostnamelen
    651 		if (n) {
    652 			icmp6stat.icp6s_reflect++;
    653 			icmp6stat.icp6s_outhist[ICMP6_WRUREPLY]++;
    654 			icmp6_reflect(n, noff);
    655 		}
    656 		break;
    657 	    }
    658 
    659 	case ICMP6_WRUREPLY:
    660 		if (code != 0)
    661 			goto badcode;
    662 		break;
    663 
    664 	case ND_ROUTER_SOLICIT:
    665 		icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routersolicit);
    666 		if (code != 0)
    667 			goto badcode;
    668 		if (icmp6len < sizeof(struct nd_router_solicit))
    669 			goto badlen;
    670 		IP6_EXTHDR_CHECK(m, off, icmp6len, IPPROTO_DONE);
    671 		nd6_rs_input(m, off, icmp6len);
    672 		/* m stays. */
    673 		break;
    674 
    675 	case ND_ROUTER_ADVERT:
    676 		icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_routeradvert);
    677 		if (code != 0)
    678 			goto badcode;
    679 		if (icmp6len < sizeof(struct nd_router_advert))
    680 			goto badlen;
    681 		IP6_EXTHDR_CHECK(m, off, icmp6len, IPPROTO_DONE);
    682 		nd6_ra_input(m, off, icmp6len);
    683 		/* m stays. */
    684 		break;
    685 
    686 	case ND_NEIGHBOR_SOLICIT:
    687 		icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighborsolicit);
    688 		if (code != 0)
    689 			goto badcode;
    690 		if (icmp6len < sizeof(struct nd_neighbor_solicit))
    691 			goto badlen;
    692 		IP6_EXTHDR_CHECK(m, off, icmp6len, IPPROTO_DONE);
    693 		nd6_ns_input(m, off, icmp6len);
    694 		/* m stays. */
    695 		break;
    696 
    697 	case ND_NEIGHBOR_ADVERT:
    698 		icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_neighboradvert);
    699 		if (code != 0)
    700 			goto badcode;
    701 		if (icmp6len < sizeof(struct nd_neighbor_advert))
    702 			goto badlen;
    703 		IP6_EXTHDR_CHECK(m, off, icmp6len, IPPROTO_DONE);
    704 		nd6_na_input(m, off, icmp6len);
    705 		/* m stays. */
    706 		break;
    707 
    708 	case ND_REDIRECT:
    709 		icmp6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_redirect);
    710 		if (code != 0)
    711 			goto badcode;
    712 		if (icmp6len < sizeof(struct nd_redirect))
    713 			goto badlen;
    714 		icmp6_redirect_input(m, off);
    715 		/* m stays. */
    716 		break;
    717 
    718 	case ICMP6_ROUTER_RENUMBERING:
    719 		if (code != ICMP6_ROUTER_RENUMBERING_COMMAND &&
    720 		    code != ICMP6_ROUTER_RENUMBERING_RESULT)
    721 			goto badcode;
    722 		if (icmp6len < sizeof(struct icmp6_router_renum))
    723 			goto badlen;
    724 		break;
    725 
    726 	default:
    727 		printf("icmp6_input: unknown type %d(src=%s, dst=%s, ifid=%d)\n",
    728 		       icmp6->icmp6_type, ip6_sprintf(&ip6->ip6_src),
    729 		       ip6_sprintf(&ip6->ip6_dst),
    730 		       m->m_pkthdr.rcvif ? m->m_pkthdr.rcvif->if_index : 0);
    731 		if (icmp6->icmp6_type < ICMP6_ECHO_REQUEST) {
    732 			/* ICMPv6 error: MUST deliver it by spec... */
    733 			code = PRC_NCMDS;
    734 			/* deliver */
    735 		} else {
    736 			/* ICMPv6 informational: MUST not deliver */
    737 			break;
    738 		}
    739 	deliver:
    740 		if (icmp6len < sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr)) {
    741 			icmp6stat.icp6s_tooshort++;
    742 			goto freeit;
    743 		}
    744 #ifndef PULLDOWN_TEST
    745 		IP6_EXTHDR_CHECK(m, off,
    746 			sizeof(struct icmp6_hdr) + sizeof(struct ip6_hdr),
    747 			IPPROTO_DONE);
    748 		icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off);
    749 #else
    750 		IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off,
    751 			sizeof(*icmp6) + sizeof(struct ip6_hdr));
    752 		if (icmp6 == NULL) {
    753 			icmp6stat.icp6s_tooshort++;
    754 			return IPPROTO_DONE;
    755 		}
    756 #endif
    757 		bzero(&icmp6src, sizeof(icmp6src));
    758 		icmp6src.sin6_len = sizeof(struct sockaddr_in6);
    759 		icmp6src.sin6_family = AF_INET6;
    760 		icmp6src.sin6_addr = ((struct ip6_hdr *)(icmp6 + 1))->ip6_dst;
    761 
    762 		/* Detect the upper level protocol */
    763 	    {
    764 		void (*ctlfunc) __P((int, struct sockaddr *, void *));
    765 		struct ip6_hdr *eip6 = (struct ip6_hdr *)(icmp6 + 1);
    766 		u_int8_t nxt = eip6->ip6_nxt;
    767 		int eoff = off + sizeof(struct icmp6_hdr) +
    768 			sizeof(struct ip6_hdr);
    769 		struct ip6ctlparam ip6cp;
    770 
    771 		while (1) { /* XXX: should avoid inf. loop explicitly? */
    772 			struct ip6_ext *eh;
    773 
    774 			switch(nxt) {
    775 			case IPPROTO_ESP:
    776 			case IPPROTO_NONE:
    777 				goto passit;
    778 			case IPPROTO_HOPOPTS:
    779 			case IPPROTO_DSTOPTS:
    780 			case IPPROTO_ROUTING:
    781 			case IPPROTO_AH:
    782 			case IPPROTO_FRAGMENT:
    783 #ifndef PULLDOWN_TEST
    784 				IP6_EXTHDR_CHECK(m, 0, eoff +
    785 						 sizeof(struct ip6_ext),
    786 						 IPPROTO_DONE);
    787 				eh = (struct ip6_ext *)(mtod(m, caddr_t)
    788 							+ eoff);
    789 #else
    790 				IP6_EXTHDR_GET(eh, struct ip6_ext *, m,
    791 					eoff, sizeof(*eh));
    792 				if (eh == NULL) {
    793 					icmp6stat.icp6s_tooshort++;
    794 					return IPPROTO_DONE;
    795 				}
    796 #endif
    797 				if (nxt == IPPROTO_AH)
    798 					eoff += (eh->ip6e_len + 2) << 2;
    799 				else if (nxt == IPPROTO_FRAGMENT)
    800 					eoff += sizeof(struct ip6_frag);
    801 				else
    802 					eoff += (eh->ip6e_len + 1) << 3;
    803 				nxt = eh->ip6e_nxt;
    804 				break;
    805 			default:
    806 				goto notify;
    807 			}
    808 		}
    809 	    notify:
    810 #ifndef PULLDOWN_TEST
    811 		icmp6 = (struct icmp6_hdr *)(mtod(m, caddr_t) + off);
    812 #else
    813 		IP6_EXTHDR_GET(icmp6, struct icmp6_hdr *, m, off,
    814 			sizeof(*icmp6) + sizeof(struct ip6_hdr));
    815 		if (icmp6 == NULL) {
    816 			icmp6stat.icp6s_tooshort++;
    817 			return IPPROTO_DONE;
    818 		}
    819 #endif
    820 		ctlfunc = (void (*) __P((int, struct sockaddr *, void *)))
    821 			(inet6sw[ip6_protox[nxt]].pr_ctlinput);
    822 		if (ctlfunc) {
    823 			ip6cp.ip6c_m = m;
    824 			ip6cp.ip6c_ip6 = (struct ip6_hdr *)(icmp6 + 1);
    825 			ip6cp.ip6c_off = eoff;
    826 			(*ctlfunc)(code, (struct sockaddr *)&icmp6src, &ip6cp);
    827 		}
    828 	    }
    829 		break;
    830 
    831 	badcode:
    832 		icmp6stat.icp6s_badcode++;
    833 		break;
    834 
    835 	badlen:
    836 		icmp6stat.icp6s_badlen++;
    837 		break;
    838 	}
    839 
    840  passit:
    841 	icmp6_rip6_input(&m, *offp);
    842 	return IPPROTO_DONE;
    843 
    844  freeit:
    845 	m_freem(m);
    846 	return IPPROTO_DONE;
    847 }
    848 
    849 /*
    850  * Process a Node Information Query
    851  */
    852 #ifndef offsetof		/* XXX */
    853 #define	offsetof(type, member)	((size_t)(&((type *)0)->member))
    854 #endif
    855 
    856 static struct mbuf *
    857 ni6_input(m, off)
    858 	struct mbuf *m;
    859 	int off;
    860 {
    861 	struct icmp6_nodeinfo *ni6, *nni6;
    862 	struct mbuf *n = NULL;
    863 	u_int16_t qtype;
    864 	int replylen = sizeof(struct ip6_hdr) + sizeof(struct icmp6_nodeinfo);
    865 	struct ni_reply_fqdn *fqdn;
    866 	int addrs;		/* for NI_QTYPE_NODEADDR */
    867 	struct ifnet *ifp = NULL; /* for NI_QTYPE_NODEADDR */
    868 
    869 #ifndef PULLDOWN_TEST
    870 	ni6 = (struct icmp6_nodeinfo *)(mtod(m, caddr_t) + off);
    871 #else
    872 	IP6_EXTHDR_GET(ni6, struct icmp6_nodeinfo *, m, off, sizeof(*ni6));
    873 	if (ni6 == NULL) {
    874 		/* m is already reclaimed */
    875 		return NULL;
    876 	}
    877 #endif
    878 	qtype = ntohs(ni6->ni_qtype);
    879 
    880 	switch(qtype) {
    881 	 case NI_QTYPE_NOOP:
    882 		 break;		/* no reply data */
    883 	 case NI_QTYPE_SUPTYPES:
    884 		 goto bad;	/* xxx: to be implemented */
    885 		 break;
    886 	 case NI_QTYPE_FQDN:
    887 		 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_name) +
    888 			 hostnamelen;
    889 		 break;
    890 	 case NI_QTYPE_NODEADDR:
    891 		 addrs = ni6_addrs(ni6, m, &ifp);
    892 		 if ((replylen += addrs * sizeof(struct in6_addr)) > MCLBYTES)
    893 			 replylen = MCLBYTES; /* XXX: we'll truncate later */
    894 
    895 		 break;
    896 	 default:
    897 		 /*
    898 		  * XXX: We must return a reply with the ICMP6 code
    899 		  * `unknown Qtype' in this case. However we regard the case
    900 		  * as an FQDN query for backward compatibility.
    901 		  * Older versions set a random value to this field,
    902 		  * so it rarely varies in the defined qtypes.
    903 		  * But the mechanism is not reliable...
    904 		  * maybe we should obsolete older versions.
    905 		  */
    906 		 qtype = NI_QTYPE_FQDN;
    907 		 replylen += offsetof(struct ni_reply_fqdn, ni_fqdn_name) +
    908 			 hostnamelen;
    909 		 break;
    910 	}
    911 
    912 	/* allocate a mbuf to reply. */
    913 	MGETHDR(n, M_DONTWAIT, m->m_type);
    914 	if (n == NULL) {
    915 		m_freem(m);
    916 		return(NULL);
    917 	}
    918 	M_COPY_PKTHDR(n, m); /* just for recvif */
    919 	if (replylen > MHLEN) {
    920 		if (replylen > MCLBYTES)
    921 			 /*
    922 			  * XXX: should we try to allocate more? But MCLBYTES is
    923 			  * probably much larger than IPV6_MMTU...
    924 			  */
    925 			goto bad;
    926 		MCLGET(n, M_DONTWAIT);
    927 		if ((n->m_flags & M_EXT) == 0) {
    928 			goto bad;
    929 		}
    930 	}
    931 	n->m_pkthdr.len = n->m_len = replylen;
    932 
    933 	/* copy mbuf header and IPv6 + Node Information base headers */
    934 	bcopy(mtod(m, caddr_t), mtod(n, caddr_t), sizeof(struct ip6_hdr));
    935 	nni6 = (struct icmp6_nodeinfo *)(mtod(n, struct ip6_hdr *) + 1);
    936 	bcopy((caddr_t)ni6, (caddr_t)nni6, sizeof(struct icmp6_nodeinfo));
    937 
    938 	/* qtype dependent procedure */
    939 	switch (qtype) {
    940 	 case NI_QTYPE_NOOP:
    941 		 nni6->ni_flags = 0;
    942 		 break;
    943 	 case NI_QTYPE_SUPTYPES:
    944 		 goto bad;	/* xxx: to be implemented */
    945 		 break;
    946 	 case NI_QTYPE_FQDN:
    947 		 if (hostnamelen > 255) { /* XXX: rare case, but may happen */
    948 			 printf("ni6_input: "
    949 				"hostname length(%d) is too large for reply\n",
    950 				hostnamelen);
    951 			 goto bad;
    952 		 }
    953 		 fqdn = (struct ni_reply_fqdn *)(mtod(n, caddr_t) +
    954 						 sizeof(struct ip6_hdr) +
    955 						 sizeof(struct icmp6_nodeinfo));
    956 		 nni6->ni_flags = 0; /* XXX: meaningless TTL */
    957 		 fqdn->ni_fqdn_ttl = 0;	/* ditto. */
    958 		 fqdn->ni_fqdn_namelen = hostnamelen;
    959 		 bcopy(hostname, &fqdn->ni_fqdn_name[0], hostnamelen);
    960 		 break;
    961 	 case NI_QTYPE_NODEADDR:
    962 	 {
    963 		 int lenlim, copied;
    964 
    965 		 if (n->m_flags & M_EXT)
    966 			 lenlim = MCLBYTES - sizeof(struct ip6_hdr) -
    967 				 sizeof(struct icmp6_nodeinfo);
    968 		 else
    969 			 lenlim = MHLEN - sizeof(struct ip6_hdr) -
    970 				 sizeof(struct icmp6_nodeinfo);
    971 		 copied = ni6_store_addrs(ni6, nni6, ifp, lenlim);
    972 		 /* XXX: reset mbuf length */
    973 		 n->m_pkthdr.len = n->m_len = sizeof(struct ip6_hdr) +
    974 			 sizeof(struct icmp6_nodeinfo) + copied;
    975 		 break;
    976 	 }
    977 	 default:
    978 		 break;		/* XXX impossible! */
    979 	}
    980 
    981 	nni6->ni_type = ICMP6_NI_REPLY;
    982 	nni6->ni_code = ICMP6_NI_SUCESS;
    983 	m_freem(m);
    984 	return(n);
    985 
    986   bad:
    987 	m_freem(m);
    988 	if (n)
    989 		m_freem(n);
    990 	return(NULL);
    991 }
    992 #undef hostnamelen
    993 
    994 /*
    995  * calculate the number of addresses to be returned in the node info reply.
    996  */
    997 static int
    998 ni6_addrs(ni6, m, ifpp)
    999 	struct icmp6_nodeinfo *ni6;
   1000 	struct mbuf *m;
   1001 	struct ifnet **ifpp;
   1002 {
   1003 	register struct ifnet *ifp;
   1004 	register struct in6_ifaddr *ifa6;
   1005 	register struct ifaddr *ifa;
   1006 	struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
   1007 	int addrs = 0, addrsofif, iffound = 0;
   1008 
   1009 	for (ifp = TAILQ_FIRST(&ifnet); ifp; ifp = TAILQ_NEXT(ifp, if_list))
   1010 	{
   1011 		addrsofif = 0;
   1012 		for (ifa = ifp->if_addrlist.tqh_first; ifa;
   1013 		     ifa = ifa->ifa_list.tqe_next)
   1014 		{
   1015 			if (ifa->ifa_addr->sa_family != AF_INET6)
   1016 				continue;
   1017 			ifa6 = (struct in6_ifaddr *)ifa;
   1018 
   1019 			if (!(ni6->ni_flags & NI_NODEADDR_FLAG_ALL) &&
   1020 			    IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst,
   1021 					       &ifa6->ia_addr.sin6_addr))
   1022 				iffound = 1;
   1023 
   1024 			if (ifa6->ia6_flags & IN6_IFF_ANYCAST)
   1025 				continue; /* we need only unicast addresses */
   1026 
   1027 			if ((ni6->ni_flags & (NI_NODEADDR_FLAG_LINKLOCAL |
   1028 					      NI_NODEADDR_FLAG_SITELOCAL |
   1029 					      NI_NODEADDR_FLAG_GLOBAL)) == 0)
   1030 				continue;
   1031 
   1032 			/* What do we have to do about ::1? */
   1033 			switch(in6_addrscope(&ifa6->ia_addr.sin6_addr)) {
   1034 			 case IPV6_ADDR_SCOPE_LINKLOCAL:
   1035 				if (ni6->ni_flags & NI_NODEADDR_FLAG_LINKLOCAL)
   1036 					addrsofif++;
   1037 				break;
   1038 			 case IPV6_ADDR_SCOPE_SITELOCAL:
   1039 				if (ni6->ni_flags & NI_NODEADDR_FLAG_SITELOCAL)
   1040 					addrsofif++;
   1041 				break;
   1042 			 case IPV6_ADDR_SCOPE_GLOBAL:
   1043 				 if (ni6->ni_flags & NI_NODEADDR_FLAG_GLOBAL)
   1044 					 addrsofif++;
   1045 				 break;
   1046 			 default:
   1047 				 continue;
   1048 			}
   1049 		}
   1050 		if (iffound) {
   1051 			*ifpp = ifp;
   1052 			return(addrsofif);
   1053 		}
   1054 
   1055 		addrs += addrsofif;
   1056 	}
   1057 
   1058 	return(addrs);
   1059 }
   1060 
   1061 static int
   1062 ni6_store_addrs(ni6, nni6, ifp0, resid)
   1063 	struct icmp6_nodeinfo *ni6, *nni6;
   1064 	struct ifnet *ifp0;
   1065 	int resid;
   1066 {
   1067 	register struct ifnet *ifp = ifp0 ? ifp0 : TAILQ_FIRST(&ifnet);
   1068 	register struct in6_ifaddr *ifa6;
   1069 	register struct ifaddr *ifa;
   1070 	int docopy, copied = 0;
   1071 	u_char *cp = (u_char *)(nni6 + 1);
   1072 
   1073 	if (ifp0 == NULL && !(ni6->ni_flags & NI_NODEADDR_FLAG_ALL))
   1074 		return(0);	/* needless to copy */
   1075 
   1076 	for (; ifp; ifp = TAILQ_NEXT(ifp, if_list))
   1077 	{
   1078 		for (ifa = ifp->if_addrlist.tqh_first; ifa;
   1079 		     ifa = ifa->ifa_list.tqe_next)
   1080 		{
   1081 			docopy = 0;
   1082 
   1083 			if (ifa->ifa_addr->sa_family != AF_INET6)
   1084 				continue;
   1085 			ifa6 = (struct in6_ifaddr *)ifa;
   1086 
   1087 			if (ifa6->ia6_flags & IN6_IFF_ANYCAST) {
   1088 				/* just experimental. not in the spec. */
   1089 				if (ni6->ni_flags & NI_NODEADDR_FLAG_ANYCAST)
   1090 					docopy = 1;
   1091 				else
   1092 					continue;
   1093 			}
   1094 			else {	/* unicast address */
   1095 				if (ni6->ni_flags & NI_NODEADDR_FLAG_ANYCAST)
   1096 					continue;
   1097 				else
   1098 					docopy = 1;
   1099 			}
   1100 
   1101 			/* What do we have to do about ::1? */
   1102 			switch(in6_addrscope(&ifa6->ia_addr.sin6_addr)) {
   1103 			 case IPV6_ADDR_SCOPE_LINKLOCAL:
   1104 				if (ni6->ni_flags & NI_NODEADDR_FLAG_LINKLOCAL)
   1105 					docopy = 1;
   1106 				break;
   1107 			 case IPV6_ADDR_SCOPE_SITELOCAL:
   1108 				if (ni6->ni_flags & NI_NODEADDR_FLAG_SITELOCAL)
   1109 					docopy = 1;
   1110 				break;
   1111 			 case IPV6_ADDR_SCOPE_GLOBAL:
   1112 				 if (ni6->ni_flags & NI_NODEADDR_FLAG_GLOBAL)
   1113 					 docopy = 1;
   1114 				 break;
   1115 			 default:
   1116 				 continue;
   1117 			}
   1118 
   1119 			if (docopy) {
   1120 				if (resid < sizeof(struct in6_addr)) {
   1121 					/*
   1122 					 * We give up much more copy.
   1123 					 * Set the truncate flag and return.
   1124 					 */
   1125 					nni6->ni_flags |=
   1126 						NI_NODEADDR_FLAG_TRUNCATE;
   1127 					return(copied);
   1128 				}
   1129 				bcopy(&ifa6->ia_addr.sin6_addr, cp,
   1130 				      sizeof(struct in6_addr));
   1131 				/* XXX: KAME link-local hack; remove ifindex */
   1132 				if (IN6_IS_ADDR_LINKLOCAL(&ifa6->ia_addr.sin6_addr))
   1133 					((struct in6_addr *)cp)->s6_addr16[1] = 0;
   1134 				cp += sizeof(struct in6_addr);
   1135 				resid -= sizeof(struct in6_addr);
   1136 				copied += sizeof(struct in6_addr);
   1137 			}
   1138 		}
   1139 		if (ifp0)	/* we need search only on the specified IF */
   1140 			break;
   1141 	}
   1142 
   1143 	return(copied);
   1144 }
   1145 
   1146 /*
   1147  * XXX almost dup'ed code with rip6_input.
   1148  */
   1149 static int
   1150 icmp6_rip6_input(mp, off)
   1151 	struct	mbuf **mp;
   1152 	int	off;
   1153 {
   1154 	struct mbuf *m = *mp;
   1155 	register struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
   1156 	register struct in6pcb *in6p;
   1157 	struct in6pcb *last = NULL;
   1158 	struct sockaddr_in6 rip6src;
   1159 	struct icmp6_hdr *icmp6;
   1160 	struct mbuf *opts = NULL;
   1161 
   1162 	/* this is assumed to be safe. */
   1163 	icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off);
   1164 
   1165 	bzero(&rip6src, sizeof(rip6src));
   1166 	rip6src.sin6_len = sizeof(struct sockaddr_in6);
   1167 	rip6src.sin6_family = AF_INET6;
   1168 	rip6src.sin6_addr = ip6->ip6_src;
   1169 	if (IN6_IS_SCOPE_LINKLOCAL(&rip6src.sin6_addr))
   1170 		rip6src.sin6_addr.s6_addr16[1] = 0;
   1171 	if (m->m_pkthdr.rcvif) {
   1172 		if (IN6_IS_SCOPE_LINKLOCAL(&rip6src.sin6_addr))
   1173 			rip6src.sin6_scope_id = m->m_pkthdr.rcvif->if_index;
   1174 		else
   1175 			rip6src.sin6_scope_id = 0;
   1176 	} else
   1177 		rip6src.sin6_scope_id = 0;
   1178 
   1179 	for (in6p = rawin6pcb.in6p_next;
   1180 	     in6p != &rawin6pcb; in6p = in6p->in6p_next)
   1181 	{
   1182 		if (in6p->in6p_ip6_nxt != IPPROTO_ICMPV6)
   1183 			continue;
   1184 		if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr) &&
   1185 		   !IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr, &ip6->ip6_dst))
   1186 			continue;
   1187 		if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr) &&
   1188 		   !IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr, &ip6->ip6_src))
   1189 			continue;
   1190 		if (in6p->in6p_icmp6filt
   1191 		    && ICMP6_FILTER_WILLBLOCK(icmp6->icmp6_type,
   1192 				 in6p->in6p_icmp6filt))
   1193 			continue;
   1194 		if (last) {
   1195 			struct	mbuf *n;
   1196 			if ((n = m_copy(m, 0, (int)M_COPYALL)) != NULL) {
   1197 				if (last->in6p_flags & IN6P_CONTROLOPTS)
   1198 					ip6_savecontrol(last, &opts, ip6, n);
   1199 				/* strip intermediate headers */
   1200 				m_adj(n, off);
   1201 				if (sbappendaddr(&last->in6p_socket->so_rcv,
   1202 						 (struct sockaddr *)&rip6src,
   1203 						 n, opts) == 0) {
   1204 					/* should notify about lost packet */
   1205 					m_freem(n);
   1206 					if (opts)
   1207 						m_freem(opts);
   1208 				} else
   1209 					sorwakeup(last->in6p_socket);
   1210 				opts = NULL;
   1211 			}
   1212 		}
   1213 		last = in6p;
   1214 	}
   1215 	if (last) {
   1216 		if (last->in6p_flags & IN6P_CONTROLOPTS)
   1217 			ip6_savecontrol(last, &opts, ip6, m);
   1218 		/* strip intermediate headers */
   1219 		m_adj(m, off);
   1220 		if (sbappendaddr(&last->in6p_socket->so_rcv,
   1221 				(struct sockaddr *)&rip6src, m, opts) == 0) {
   1222 			m_freem(m);
   1223 			if (opts)
   1224 				m_freem(opts);
   1225 		} else
   1226 			sorwakeup(last->in6p_socket);
   1227 	} else {
   1228 		m_freem(m);
   1229 		ip6stat.ip6s_delivered--;
   1230 	}
   1231 	return IPPROTO_DONE;
   1232 }
   1233 
   1234 /*
   1235  * Reflect the ip6 packet back to the source.
   1236  * OFF points to the icmp6 header, counted from the top of the mbuf.
   1237  */
   1238 void
   1239 icmp6_reflect(m, off)
   1240 	struct	mbuf *m;
   1241 	size_t off;
   1242 {
   1243 	struct ip6_hdr *ip6;
   1244 	struct icmp6_hdr *icmp6;
   1245 	struct in6_ifaddr *ia;
   1246 	struct in6_addr t, *src = 0;
   1247 	int plen;
   1248 	int type, code;
   1249 	struct ifnet *outif = NULL;
   1250 #ifdef COMPAT_RFC1885
   1251 	int mtu = IPV6_MMTU;
   1252 	struct sockaddr_in6 *sin6 = &icmp6_reflect_rt.ro_dst;
   1253 #endif
   1254 
   1255 	/* too short to reflect */
   1256 	if (off < sizeof(struct ip6_hdr)) {
   1257 		printf("sanity fail: off=%lx, sizeof(ip6)=%lx in %s:%d\n",
   1258 		       (u_long)off, (u_long)sizeof(struct ip6_hdr),
   1259 		       __FILE__, __LINE__);
   1260 		goto bad;
   1261 	}
   1262 
   1263 	/*
   1264 	 * If there are extra headers between IPv6 and ICMPv6, strip
   1265 	 * off that header first.
   1266 	 */
   1267 	if (off > sizeof(struct ip6_hdr)) {
   1268 		size_t l;
   1269 		struct ip6_hdr nip6;
   1270 
   1271 		l = off - sizeof(struct ip6_hdr);
   1272 		m_copydata(m, 0, sizeof(nip6), (caddr_t)&nip6);
   1273 		m_adj(m, l);
   1274 		l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr);
   1275 		if (m->m_len < l) {
   1276 			if ((m = m_pullup(m, l)) == NULL)
   1277 				return;
   1278 		}
   1279 		bcopy((caddr_t)&nip6, mtod(m, caddr_t), sizeof(nip6));
   1280 	} else /* off == sizeof(struct ip6_hdr) */ {
   1281 		size_t l;
   1282 		l = sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr);
   1283 		if (m->m_len < l) {
   1284 			if ((m = m_pullup(m, l)) == NULL)
   1285 				return;
   1286 		}
   1287 	}
   1288 	plen = m->m_pkthdr.len - sizeof(struct ip6_hdr);
   1289 	ip6 = mtod(m, struct ip6_hdr *);
   1290 	ip6->ip6_nxt = IPPROTO_ICMPV6;
   1291 	icmp6 = (struct icmp6_hdr *)(ip6 + 1);
   1292 	type = icmp6->icmp6_type; /* keep type for statistics */
   1293 	code = icmp6->icmp6_code; /* ditto. */
   1294 
   1295 	t = ip6->ip6_dst;
   1296 	/*
   1297 	 * ip6_input() drops a packet if its src is multicast.
   1298 	 * So, the src is never multicast.
   1299 	 */
   1300 	ip6->ip6_dst = ip6->ip6_src;
   1301 
   1302 	/* XXX hack for link-local addresses */
   1303 	if (IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_dst))
   1304 		ip6->ip6_dst.s6_addr16[1] =
   1305 			htons(m->m_pkthdr.rcvif->if_index);
   1306 	if (IN6_IS_ADDR_LINKLOCAL(&t))
   1307 		t.s6_addr16[1] = htons(m->m_pkthdr.rcvif->if_index);
   1308 
   1309 #ifdef COMPAT_RFC1885
   1310 	/*
   1311 	 * xxx guess MTU
   1312 	 * RFC 1885 requires that echo reply should be truncated if it
   1313 	 * does not fit in with (return) path MTU, but the description was
   1314 	 * removed in the new spec.
   1315 	 */
   1316 	if (icmp6_reflect_rt.ro_rt == 0 ||
   1317 	    ! (IN6_ARE_ADDR_EQUAL(&sin6->sin6_addr, &ip6->ip6_dst))) {
   1318 		if (icmp6_reflect_rt.ro_rt) {
   1319 			icmp6_reflect_rt.ro_rt = 0;
   1320 		}
   1321 		bzero(sin6, sizeof(*sin6));
   1322 		sin6->sin6_family = PF_INET6;
   1323 		sin6->sin6_len = sizeof(struct sockaddr_in6);
   1324 		sin6->sin6_addr = ip6->ip6_dst;
   1325 
   1326 		rtalloc((struct route *)&icmp6_reflect_rt.ro_rt);
   1327 	}
   1328 
   1329 	if (icmp6_reflect_rt.ro_rt == 0)
   1330 		goto bad;
   1331 
   1332 	if ((icmp6_reflect_rt.ro_rt->rt_flags & RTF_HOST)
   1333 	    && mtu < icmp6_reflect_rt.ro_rt->rt_ifp->if_mtu)
   1334 		mtu = icmp6_reflect_rt.ro_rt->rt_rmx.rmx_mtu;
   1335 
   1336 	if (mtu < m->m_pkthdr.len) {
   1337 		plen -= (m->m_pkthdr.len - mtu);
   1338 		m_adj(m, mtu - m->m_pkthdr.len);
   1339 	}
   1340 #endif
   1341 	/*
   1342 	 * If the incoming packet was addressed directly to us(i.e. unicast),
   1343 	 * use dst as the src for the reply.
   1344 	 */
   1345 	for (ia = in6_ifaddr; ia; ia = ia->ia_next)
   1346 		if (IN6_ARE_ADDR_EQUAL(&t, &ia->ia_addr.sin6_addr) &&
   1347 		    (ia->ia6_flags & IN6_IFF_ANYCAST) == 0) {
   1348 			src = &t;
   1349 			break;
   1350 		}
   1351 	if (ia == NULL && IN6_IS_ADDR_LINKLOCAL(&t) && (m->m_flags & M_LOOP)) {
   1352 		/*
   1353 		 * This is the case if the dst is our link-local address
   1354 		 * and the sender is also ourseleves.
   1355 		 */
   1356 		src = &t;
   1357 	}
   1358 
   1359 	if (src == 0)
   1360 		/*
   1361 		 * We have not multicast routing yet. So this case matches
   1362 		 * to our multicast, our anycast or not to our unicast.
   1363 		 * Select a source address which has the same scope.
   1364 		 */
   1365 		if ((ia = in6_ifawithscope(m->m_pkthdr.rcvif, &t)) != 0)
   1366 			src = &IA6_SIN6(ia)->sin6_addr;
   1367 
   1368 	if (src == 0)
   1369 		goto bad;
   1370 
   1371 	ip6->ip6_src = *src;
   1372 
   1373 	ip6->ip6_flow = 0;
   1374 	ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
   1375 	ip6->ip6_vfc |= IPV6_VERSION;
   1376 	ip6->ip6_nxt = IPPROTO_ICMPV6;
   1377 	if (m->m_pkthdr.rcvif) {
   1378 		/* XXX: This may not be the outgoing interface */
   1379 		ip6->ip6_hlim = nd_ifinfo[m->m_pkthdr.rcvif->if_index].chlim;
   1380 	}
   1381 
   1382 	icmp6->icmp6_cksum = 0;
   1383 	icmp6->icmp6_cksum = in6_cksum(m, IPPROTO_ICMPV6,
   1384 					sizeof(struct ip6_hdr), plen);
   1385 
   1386 	/*
   1387 	 * xxx option handling
   1388 	 */
   1389 
   1390 	m->m_flags &= ~(M_BCAST|M_MCAST);
   1391 #ifdef IPSEC
   1392 	m->m_pkthdr.rcvif = NULL;
   1393 #endif /*IPSEC*/
   1394 
   1395 #ifdef COMPAT_RFC1885
   1396 	ip6_output(m, NULL, &icmp6_reflect_rt, 0, NULL, &outif);
   1397 #else
   1398 	ip6_output(m, NULL, NULL, 0, NULL, &outif);
   1399 #endif
   1400 	if (outif)
   1401 		icmp6_ifoutstat_inc(outif, type, code);
   1402 
   1403 	return;
   1404 
   1405  bad:
   1406 	m_freem(m);
   1407 	return;
   1408 }
   1409 
   1410 void
   1411 icmp6_fasttimo()
   1412 {
   1413 	mld6_fasttimeo();
   1414 }
   1415 
   1416 static const char *
   1417 icmp6_redirect_diag(src6, dst6, tgt6)
   1418 	struct in6_addr *src6;
   1419 	struct in6_addr *dst6;
   1420 	struct in6_addr *tgt6;
   1421 {
   1422 	static char buf[1024];
   1423 	snprintf(buf, sizeof(buf), "(src=%s dst=%s tgt=%s)",
   1424 		ip6_sprintf(src6), ip6_sprintf(dst6), ip6_sprintf(tgt6));
   1425 	return buf;
   1426 }
   1427 
   1428 void
   1429 icmp6_redirect_input(m, off)
   1430 	register struct mbuf *m;
   1431 	int off;
   1432 {
   1433 	struct ifnet *ifp = m->m_pkthdr.rcvif;
   1434 	struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
   1435 	struct nd_redirect *nd_rd = (struct nd_redirect *)((caddr_t)ip6 + off);
   1436 	int icmp6len = ntohs(ip6->ip6_plen);
   1437 	char *lladdr = NULL;
   1438 	int lladdrlen = 0;
   1439 	u_char *redirhdr = NULL;
   1440 	int redirhdrlen = 0;
   1441 	struct rtentry *rt = NULL;
   1442 	int is_router;
   1443 	int is_onlink;
   1444 	struct in6_addr src6 = ip6->ip6_src;
   1445 	struct in6_addr redtgt6 = nd_rd->nd_rd_target;
   1446 	struct in6_addr reddst6 = nd_rd->nd_rd_dst;
   1447 	union nd_opts ndopts;
   1448 
   1449 	if (!m || !ifp)
   1450 		return;
   1451 
   1452 	/* XXX if we are router, we don't update route by icmp6 redirect */
   1453 	if (ip6_forwarding)
   1454 		return;
   1455 	if (!icmp6_rediraccept)
   1456 		return;
   1457 
   1458 	if (IN6_IS_ADDR_LINKLOCAL(&redtgt6))
   1459 		redtgt6.s6_addr16[1] = htons(ifp->if_index);
   1460 	if (IN6_IS_ADDR_LINKLOCAL(&reddst6))
   1461 		reddst6.s6_addr16[1] = htons(ifp->if_index);
   1462 
   1463 	/* validation */
   1464 	if (!IN6_IS_ADDR_LINKLOCAL(&src6)) {
   1465 		log(LOG_ERR,
   1466 			"ICMP6 redirect sent from %s rejected; "
   1467 			"must be from linklocal\n", ip6_sprintf(&src6));
   1468 		return;
   1469 	}
   1470 	if (ip6->ip6_hlim != 255) {
   1471 		log(LOG_ERR,
   1472 			"ICMP6 redirect sent from %s rejected; "
   1473 			"hlim=%d (must be 255)\n",
   1474 			ip6_sprintf(&src6), ip6->ip6_hlim);
   1475 		return;
   1476 	}
   1477     {
   1478 	/* ip6->ip6_src must be equal to gw for icmp6->icmp6_reddst */
   1479 	struct sockaddr_in6 sin6;
   1480 	struct in6_addr *gw6;
   1481 
   1482 	bzero(&sin6, sizeof(sin6));
   1483 	sin6.sin6_family = AF_INET6;
   1484 	sin6.sin6_len = sizeof(struct sockaddr_in6);
   1485 	bcopy(&reddst6, &sin6.sin6_addr, sizeof(reddst6));
   1486 	rt = rtalloc1((struct sockaddr *)&sin6, 0
   1487 		      );
   1488 	if (rt) {
   1489 		gw6 = &(((struct sockaddr_in6 *)rt->rt_gateway)->sin6_addr);
   1490 		if (bcmp(&src6, gw6, sizeof(struct in6_addr)) != 0) {
   1491 			log(LOG_ERR,
   1492 				"ICMP6 redirect rejected; "
   1493 				"not equal to gw-for-src=%s (must be same): "
   1494 				"%s\n",
   1495 				ip6_sprintf(gw6),
   1496 				icmp6_redirect_diag(&src6, &reddst6, &redtgt6));
   1497 			RTFREE(rt);
   1498 			return;
   1499 		}
   1500 	} else {
   1501 		log(LOG_ERR,
   1502 			"ICMP6 redirect rejected; "
   1503 			"no route found for redirect dst: %s\n",
   1504 			icmp6_redirect_diag(&src6, &reddst6, &redtgt6));
   1505 		return;
   1506 	}
   1507 	RTFREE(rt);
   1508 	rt = NULL;
   1509     }
   1510 	if (IN6_IS_ADDR_MULTICAST(&reddst6)) {
   1511 		log(LOG_ERR,
   1512 			"ICMP6 redirect rejected; "
   1513 			"redirect dst must be unicast: %s\n",
   1514 			icmp6_redirect_diag(&src6, &reddst6, &redtgt6));
   1515 		return;
   1516 	}
   1517 
   1518 	is_router = is_onlink = 0;
   1519 	if (IN6_IS_ADDR_LINKLOCAL(&redtgt6))
   1520 		is_router = 1;	/* router case */
   1521 	if (bcmp(&redtgt6, &reddst6, sizeof(redtgt6)) == 0)
   1522 		is_onlink = 1;	/* on-link destination case */
   1523 	if (!is_router && !is_onlink) {
   1524 		log(LOG_ERR,
   1525 			"ICMP6 redirect rejected; "
   1526 			"neither router case nor onlink case: %s\n",
   1527 			icmp6_redirect_diag(&src6, &reddst6, &redtgt6));
   1528 		return;
   1529 	}
   1530 	/* validation passed */
   1531 
   1532 	icmp6len -= sizeof(*nd_rd);
   1533 	nd6_option_init(nd_rd + 1, icmp6len, &ndopts);
   1534 	if (nd6_options(&ndopts) < 0) {
   1535 		log(LOG_INFO, "icmp6_redirect_input: "
   1536 			"invalid ND option, rejected: %s\n",
   1537 			icmp6_redirect_diag(&src6, &reddst6, &redtgt6));
   1538 		return;
   1539 	}
   1540 
   1541 	if (ndopts.nd_opts_tgt_lladdr) {
   1542 		lladdr = (char *)(ndopts.nd_opts_tgt_lladdr + 1);
   1543 		lladdrlen = ndopts.nd_opts_tgt_lladdr->nd_opt_len << 3;
   1544 	}
   1545 
   1546 	if (ndopts.nd_opts_rh) {
   1547 		redirhdrlen = ndopts.nd_opts_rh->nd_opt_rh_len;
   1548 		redirhdr = (u_char *)(ndopts.nd_opts_rh + 1); /* xxx */
   1549 	}
   1550 
   1551 	if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) {
   1552 		log(LOG_INFO,
   1553 			"icmp6_redirect_input: lladdrlen mismatch for %s "
   1554 			"(if %d, icmp6 packet %d): %s\n",
   1555 			ip6_sprintf(&redtgt6), ifp->if_addrlen, lladdrlen - 2,
   1556 			icmp6_redirect_diag(&src6, &reddst6, &redtgt6));
   1557 	}
   1558 
   1559 	/* RFC 2461 8.3 */
   1560 	nd6_cache_lladdr(ifp, &redtgt6, lladdr, lladdrlen, ND_REDIRECT,
   1561 			 is_onlink ? ND_REDIRECT_ONLINK : ND_REDIRECT_ROUTER);
   1562 
   1563 	if (!is_onlink) {	/* better router case. perform rtredirect. */
   1564 		/* perform rtredirect */
   1565 		struct sockaddr_in6 sdst;
   1566 		struct sockaddr_in6 sgw;
   1567 		struct sockaddr_in6 ssrc;
   1568 
   1569 		bzero(&sdst, sizeof(sdst));
   1570 		bzero(&sgw, sizeof(sgw));
   1571 		bzero(&ssrc, sizeof(ssrc));
   1572 		sdst.sin6_family = sgw.sin6_family = ssrc.sin6_family = AF_INET6;
   1573 		sdst.sin6_len = sgw.sin6_len = ssrc.sin6_len =
   1574 			sizeof(struct sockaddr_in6);
   1575 		bcopy(&redtgt6, &sgw.sin6_addr, sizeof(struct in6_addr));
   1576 		bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr));
   1577 		bcopy(&src6, &ssrc.sin6_addr, sizeof(struct in6_addr));
   1578 		rtredirect((struct sockaddr *)&sdst, (struct sockaddr *)&sgw,
   1579 			   (struct sockaddr *)NULL, RTF_GATEWAY | RTF_HOST,
   1580 			   (struct sockaddr *)&ssrc,
   1581 			   (struct rtentry **)NULL
   1582 			   );
   1583 	}
   1584 	/* finally update cached route in each socket via pfctlinput */
   1585     {
   1586 	struct sockaddr_in6 sdst;
   1587 #if 1
   1588 #else
   1589 	struct ip6protosw *pr;
   1590 #endif
   1591 
   1592 	bzero(&sdst, sizeof(sdst));
   1593 	sdst.sin6_family = AF_INET6;
   1594 	sdst.sin6_len = sizeof(struct sockaddr_in6);
   1595 	bcopy(&reddst6, &sdst.sin6_addr, sizeof(struct in6_addr));
   1596 #if 1
   1597 	pfctlinput(PRC_REDIRECT_HOST, (struct sockaddr *)&sdst);
   1598 #else
   1599 	/*
   1600 	 * do not use pfctlinput() here, we have different prototype for
   1601 	 * xx_ctlinput() in ip6proto.
   1602 	 */
   1603 	for (pr = (struct ip6protosw *)inet6domain.dom_protosw;
   1604 	     pr < (struct ip6protosw *)inet6domain.dom_protoswNPROTOSW;
   1605 	     pr++) {
   1606 		if (pr->pr_ctlinput) {
   1607 			(*pr->pr_ctlinput)(PRC_REDIRECT_HOST,
   1608 				(struct sockaddr *)&sdst, NULL, NULL, 0);
   1609 		}
   1610 	}
   1611 #endif
   1612 #ifdef IPSEC
   1613 	key_sa_routechange((struct sockaddr *)&sdst);
   1614 #endif
   1615     }
   1616 }
   1617 
   1618 void
   1619 icmp6_redirect_output(m0, rt)
   1620 	struct mbuf *m0;
   1621 	struct rtentry *rt;
   1622 {
   1623 	struct ifnet *ifp;	/* my outgoing interface */
   1624 	struct in6_addr *ifp_ll6;
   1625 	struct in6_addr *router_ll6;
   1626 	struct ip6_hdr *sip6;	/* m0 as struct ip6_hdr */
   1627 	struct mbuf *m = NULL;	/* newly allocated one */
   1628 	struct ip6_hdr *ip6;	/* m as struct ip6_hdr */
   1629 	struct nd_redirect *nd_rd;
   1630 	size_t maxlen;
   1631 	u_char *p;
   1632 	struct ifnet *outif = NULL;
   1633 
   1634 	/* if we are not router, we don't send icmp6 redirect */
   1635 	if (!ip6_forwarding || ip6_accept_rtadv)
   1636 		goto fail;
   1637 
   1638 	/* sanity check */
   1639 	if (!m0 || !rt || !(rt->rt_flags & RTF_UP) || !(ifp = rt->rt_ifp))
   1640 		goto fail;
   1641 
   1642 	/*
   1643 	 * Address check:
   1644 	 *  the source address must identify a neighbor, and
   1645 	 *  the destination address must not be a multicast address
   1646 	 *  [RFC 2461, sec 8.2]
   1647 	 */
   1648 	sip6 = mtod(m0, struct ip6_hdr *);
   1649 	if (nd6_is_addr_neighbor(&sip6->ip6_src, ifp) == 0)
   1650 		goto fail;
   1651 	if (IN6_IS_ADDR_MULTICAST(&sip6->ip6_dst))
   1652 		goto fail;	/* what should we do here? */
   1653 
   1654 	/* rate limit */
   1655 	if (icmp6_ratelimit(&sip6->ip6_src, ND_REDIRECT, 0))
   1656 		goto fail;
   1657 
   1658 	/*
   1659 	 * Since we are going to append up to 1280 bytes (= IPV6_MMTU),
   1660 	 * we almost always ask for an mbuf cluster for simplicity.
   1661 	 * (MHLEN < IPV6_MMTU is almost always true)
   1662 	 */
   1663 	MGETHDR(m, M_DONTWAIT, MT_HEADER);
   1664 	if (!m)
   1665 		goto fail;
   1666 	if (MHLEN < IPV6_MMTU)
   1667 		MCLGET(m, M_DONTWAIT);
   1668 	maxlen = (m->m_flags & M_EXT) ? MCLBYTES : MHLEN;
   1669 	maxlen = min(IPV6_MMTU, maxlen);
   1670 	/* just for safety */
   1671 	if (maxlen < sizeof(struct ip6_hdr) + sizeof(struct icmp6_hdr))
   1672 		goto fail;
   1673 
   1674 	{
   1675 		/* get ip6 linklocal address for ifp(my outgoing interface). */
   1676 		struct in6_ifaddr *ia = in6ifa_ifpforlinklocal(ifp);
   1677 		if (ia == NULL)
   1678 			goto fail;
   1679 		ifp_ll6 = &ia->ia_addr.sin6_addr;
   1680 	}
   1681 
   1682 	/* get ip6 linklocal address for the router. */
   1683 	if (rt->rt_gateway && (rt->rt_flags & RTF_GATEWAY)) {
   1684 		struct sockaddr_in6 *sin6;
   1685 		sin6 = (struct sockaddr_in6 *)rt->rt_gateway;
   1686 		router_ll6 = &sin6->sin6_addr;
   1687 		if (!IN6_IS_ADDR_LINKLOCAL(router_ll6))
   1688 			router_ll6 = (struct in6_addr *)NULL;
   1689 	} else
   1690 		router_ll6 = (struct in6_addr *)NULL;
   1691 
   1692 	/* ip6 */
   1693 	ip6 = mtod(m, struct ip6_hdr *);
   1694 	ip6->ip6_flow = 0;
   1695 	ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
   1696 	ip6->ip6_vfc |= IPV6_VERSION;
   1697 	/* ip6->ip6_plen will be set later */
   1698 	ip6->ip6_nxt = IPPROTO_ICMPV6;
   1699 	ip6->ip6_hlim = 255;
   1700 	/* ip6->ip6_src must be linklocal addr for my outgoing if. */
   1701 	bcopy(ifp_ll6, &ip6->ip6_src, sizeof(struct in6_addr));
   1702 	bcopy(&sip6->ip6_src, &ip6->ip6_dst, sizeof(struct in6_addr));
   1703 
   1704 	/* ND Redirect */
   1705 	nd_rd = (struct nd_redirect *)(ip6 + 1);
   1706 	nd_rd->nd_rd_type = ND_REDIRECT;
   1707 	nd_rd->nd_rd_code = 0;
   1708 	nd_rd->nd_rd_reserved = 0;
   1709 	if (rt->rt_flags & RTF_GATEWAY) {
   1710 		/*
   1711 		 * nd_rd->nd_rd_target must be a link-local address in
   1712 		 * better router cases.
   1713 		 */
   1714 		if (!router_ll6)
   1715 			goto fail;
   1716 		bcopy(router_ll6, &nd_rd->nd_rd_target,
   1717 		      sizeof(nd_rd->nd_rd_target));
   1718 		bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst,
   1719 		      sizeof(nd_rd->nd_rd_dst));
   1720 	} else {
   1721 		/* make sure redtgt == reddst */
   1722 		bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_target,
   1723 		      sizeof(nd_rd->nd_rd_target));
   1724 		bcopy(&sip6->ip6_dst, &nd_rd->nd_rd_dst,
   1725 		      sizeof(nd_rd->nd_rd_dst));
   1726 	}
   1727 
   1728 	p = (u_char *)(nd_rd + 1);
   1729 
   1730 	if (!router_ll6)
   1731 		goto nolladdropt;
   1732 
   1733     {
   1734 	/* target lladdr option */
   1735 	struct rtentry *rt_router = NULL;
   1736 	int len;
   1737 	struct sockaddr_dl *sdl;
   1738 	struct nd_opt_hdr *nd_opt;
   1739 	char *lladdr;
   1740 
   1741 	rt_router = nd6_lookup(router_ll6, 0, ifp);
   1742 	if (!rt_router)
   1743 		goto nolladdropt;
   1744 	if (!(rt_router->rt_flags & RTF_GATEWAY) &&
   1745 	    (rt_router->rt_flags & RTF_LLINFO) &&
   1746 	    (rt_router->rt_gateway->sa_family == AF_LINK) &&
   1747 	    (sdl = (struct sockaddr_dl *)rt_router->rt_gateway) &&
   1748 	    sdl->sdl_alen) {
   1749 		nd_opt = (struct nd_opt_hdr *)p;
   1750 		nd_opt->nd_opt_type = ND_OPT_TARGET_LINKADDR;
   1751 		len = 2 + ifp->if_addrlen;
   1752 		len = (len + 7) & ~7;	/*round by 8*/
   1753 		nd_opt->nd_opt_len = len >> 3;
   1754 		p += len;
   1755 		lladdr = (char *)(nd_opt + 1);
   1756 		bcopy(LLADDR(sdl), lladdr, ifp->if_addrlen);
   1757 	}
   1758     }
   1759 nolladdropt:;
   1760 
   1761 	m->m_pkthdr.len = m->m_len = p - (u_char *)ip6;
   1762 
   1763 	/* just to be safe */
   1764 #ifdef M_DECRYPTED	/*not openbsd*/
   1765 	if (m0->m_flags & M_DECRYPTED)
   1766 		goto noredhdropt;
   1767 #endif
   1768 
   1769     {
   1770 	/* redirected header option */
   1771 	int len;
   1772 	struct nd_opt_rd_hdr *nd_opt_rh;
   1773 
   1774 	/*
   1775 	 * compute the maximum size for icmp6 redirect header option.
   1776 	 * XXX room for auth header?
   1777 	 */
   1778 	len = maxlen - (p - (u_char *)ip6);
   1779 	len &= ~7;
   1780 
   1781 	/* This is just for simplicity. */
   1782 	if (m0->m_pkthdr.len != m0->m_len) {
   1783 		if (m0->m_next) {
   1784 			m_freem(m0->m_next);
   1785 			m0->m_next = NULL;
   1786 		}
   1787 		m0->m_pkthdr.len = m0->m_len;
   1788 	}
   1789 
   1790 	/*
   1791 	 * Redirected header option spec (RFC2461 4.6.3) talks nothing
   1792 	 * about padding/truncate rule for the original IP packet.
   1793 	 * From the discussion on IPv6imp in Feb 1999, the consensus was:
   1794 	 * - "attach as much as possible" is the goal
   1795 	 * - pad if not aligned (original size can be guessed by original
   1796 	 *   ip6 header)
   1797 	 * Following code adds the padding if it is simple enough,
   1798 	 * and truncates if not.
   1799 	 */
   1800 	if (m0->m_next || m0->m_pkthdr.len != m0->m_len)
   1801 		panic("assumption failed in %s:%d\n", __FILE__, __LINE__);
   1802 
   1803 	if (len - sizeof(*nd_opt_rh) < m0->m_pkthdr.len) {
   1804 		/* not enough room, truncate */
   1805 		m0->m_pkthdr.len = m0->m_len = len - sizeof(*nd_opt_rh);
   1806 	} else {
   1807 		/* enough room, pad or truncate */
   1808 		size_t extra;
   1809 
   1810 		extra = m0->m_pkthdr.len % 8;
   1811 		if (extra) {
   1812 			/* pad if easy enough, truncate if not */
   1813 			if (8 - extra <= M_TRAILINGSPACE(m0)) {
   1814 				/* pad */
   1815 				m0->m_len += (8 - extra);
   1816 				m0->m_pkthdr.len += (8 - extra);
   1817 			} else {
   1818 				/* truncate */
   1819 				m0->m_pkthdr.len -= extra;
   1820 				m0->m_len -= extra;
   1821 			}
   1822 		}
   1823 		len = m0->m_pkthdr.len + sizeof(*nd_opt_rh);
   1824 		m0->m_pkthdr.len = m0->m_len = len - sizeof(*nd_opt_rh);
   1825 	}
   1826 
   1827 	nd_opt_rh = (struct nd_opt_rd_hdr *)p;
   1828 	bzero(nd_opt_rh, sizeof(*nd_opt_rh));
   1829 	nd_opt_rh->nd_opt_rh_type = ND_OPT_REDIRECTED_HEADER;
   1830 	nd_opt_rh->nd_opt_rh_len = len >> 3;
   1831 	p += sizeof(*nd_opt_rh);
   1832 	m->m_pkthdr.len = m->m_len = p - (u_char *)ip6;
   1833 
   1834 	/* connect m0 to m */
   1835 	m->m_next = m0;
   1836 	m->m_pkthdr.len = m->m_len + m0->m_len;
   1837     }
   1838 #ifdef M_DECRYPTED	/*not openbsd*/
   1839 noredhdropt:;
   1840 #endif
   1841 
   1842 	if (IN6_IS_ADDR_LINKLOCAL(&sip6->ip6_src))
   1843 		sip6->ip6_src.s6_addr16[1] = 0;
   1844 	if (IN6_IS_ADDR_LINKLOCAL(&sip6->ip6_dst))
   1845 		sip6->ip6_dst.s6_addr16[1] = 0;
   1846 #if 0
   1847 	if (IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_src))
   1848 		ip6->ip6_src.s6_addr16[1] = 0;
   1849 	if (IN6_IS_ADDR_LINKLOCAL(&ip6->ip6_dst))
   1850 		ip6->ip6_dst.s6_addr16[1] = 0;
   1851 #endif
   1852 	if (IN6_IS_ADDR_LINKLOCAL(&nd_rd->nd_rd_target))
   1853 		nd_rd->nd_rd_target.s6_addr16[1] = 0;
   1854 	if (IN6_IS_ADDR_LINKLOCAL(&nd_rd->nd_rd_dst))
   1855 		nd_rd->nd_rd_dst.s6_addr16[1] = 0;
   1856 
   1857 	ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr));
   1858 
   1859 	nd_rd->nd_rd_cksum = 0;
   1860 	nd_rd->nd_rd_cksum
   1861 		= in6_cksum(m, IPPROTO_ICMPV6, sizeof(*ip6), ntohs(ip6->ip6_plen));
   1862 
   1863 	/* send the packet to outside... */
   1864 #ifdef IPSEC
   1865 	m->m_pkthdr.rcvif = NULL;
   1866 #endif /*IPSEC*/
   1867 	ip6_output(m, NULL, NULL, 0, NULL, &outif);
   1868 	if (outif) {
   1869 		icmp6_ifstat_inc(outif, ifs6_out_msg);
   1870 		icmp6_ifstat_inc(outif, ifs6_out_redirect);
   1871 	}
   1872 	icmp6stat.icp6s_outhist[ND_REDIRECT]++;
   1873 
   1874 	return;
   1875 
   1876 fail:
   1877 	if (m)
   1878 		m_freem(m);
   1879 	if (m0)
   1880 		m_freem(m0);
   1881 }
   1882 
   1883 /*
   1884  * ICMPv6 socket option processing.
   1885  */
   1886 int
   1887 icmp6_ctloutput(op, so, level, optname, mp)
   1888 	int op;
   1889 	struct socket *so;
   1890 	int level, optname;
   1891 	struct mbuf **mp;
   1892 {
   1893 	register struct in6pcb *in6p = sotoin6pcb(so);
   1894 	register struct mbuf *m = *mp;
   1895 	int error = 0;
   1896 
   1897 	if (level != IPPROTO_ICMPV6) {
   1898 		error = EINVAL;
   1899 		if (op == PRCO_SETOPT && m)
   1900 			(void)m_free(m);
   1901 	} else switch(op) {
   1902 	 case PRCO_SETOPT:
   1903 		 switch (optname) {
   1904 		  case ICMP6_FILTER:
   1905 		  {
   1906 			  struct icmp6_filter *p;
   1907 
   1908 			  p = mtod(m, struct icmp6_filter *);
   1909 			  if (!p || !in6p->in6p_icmp6filt) {
   1910 				  error = EINVAL;
   1911 				  break;
   1912 			  }
   1913 			  bcopy(p, in6p->in6p_icmp6filt,
   1914 				sizeof(struct icmp6_filter));
   1915 			  error = 0;
   1916 			  break;
   1917 		  }
   1918 
   1919 		  default:
   1920 			  error = ENOPROTOOPT;
   1921 			  break;
   1922 		 }
   1923 		 if (m)
   1924 			 (void)m_free(m);
   1925 		 break;
   1926 
   1927 	 case PRCO_GETOPT:
   1928 		 switch (optname) {
   1929 		  case ICMP6_FILTER:
   1930 		  {
   1931 			  struct icmp6_filter *p;
   1932 
   1933 			  if (!in6p->in6p_icmp6filt) {
   1934 				  error = EINVAL;
   1935 				  break;
   1936 			  }
   1937 			  *mp = m = m_get(M_WAIT, MT_SOOPTS);
   1938 			  m->m_len = sizeof(struct icmp6_filter);
   1939 			  p = mtod(m, struct icmp6_filter *);
   1940 			  bcopy(in6p->in6p_icmp6filt, p,
   1941 				sizeof(struct icmp6_filter));
   1942 			  error = 0;
   1943 			  break;
   1944 		  }
   1945 
   1946 		  default:
   1947 			  error = ENOPROTOOPT;
   1948 			  break;
   1949 		 }
   1950 		 break;
   1951 	}
   1952 
   1953 	return(error);
   1954 }
   1955 
   1956 /*
   1957  * Perform rate limit check.
   1958  * Returns 0 if it is okay to send the icmp6 packet.
   1959  * Returns 1 if the router SHOULD NOT send this icmp6 packet due to rate
   1960  * limitation.
   1961  *
   1962  * XXX per-destination/type check necessary?
   1963  */
   1964 static int
   1965 icmp6_ratelimit(dst, type, code)
   1966 	const struct in6_addr *dst;	/* not used at this moment */
   1967 	const int type;			/* not used at this moment */
   1968 	const int code;			/* not used at this moment */
   1969 {
   1970 	struct timeval tp;
   1971 	long sec_diff, usec_diff;
   1972 
   1973 	/* If we are not doing rate limitation, it is always okay to send */
   1974 	if (!icmp6errratelim)
   1975 		return 0;
   1976 
   1977 	tp = time;
   1978 	if (tp.tv_sec < icmp6_nextsend.tv_sec
   1979 	 || (tp.tv_sec == icmp6_nextsend.tv_sec
   1980 	  && tp.tv_usec < icmp6_nextsend.tv_usec)) {
   1981 		/* The packet is subject to rate limit */
   1982 		return 1;
   1983 	}
   1984 	sec_diff = icmp6errratelim / 1000000;
   1985 	usec_diff = icmp6errratelim % 1000000;
   1986 	icmp6_nextsend.tv_sec = tp.tv_sec + sec_diff;
   1987 	if ((tp.tv_usec = tp.tv_usec + usec_diff) >= 1000000) {
   1988 		icmp6_nextsend.tv_sec++;
   1989 		icmp6_nextsend.tv_usec -= 1000000;
   1990 	}
   1991 
   1992 	/* it is okay to send this */
   1993 	return 0;
   1994 }
   1995 
   1996 static struct rtentry *
   1997 icmp6_mtudisc_clone(dst)
   1998 	struct sockaddr *dst;
   1999 {
   2000 	struct rtentry *rt;
   2001 	int    error;
   2002 
   2003 	rt = rtalloc1(dst, 1);
   2004 	if (rt == 0)
   2005 		return NULL;
   2006 
   2007 	/* If we didn't get a host route, allocate one */
   2008 	if ((rt->rt_flags & RTF_HOST) == 0) {
   2009 		struct rtentry *nrt;
   2010 
   2011 		error = rtrequest((int) RTM_ADD, dst,
   2012 		    (struct sockaddr *) rt->rt_gateway,
   2013 		    (struct sockaddr *) 0,
   2014 		    RTF_GATEWAY | RTF_HOST | RTF_DYNAMIC, &nrt);
   2015 		if (error) {
   2016 			rtfree(rt);
   2017 			rtfree(nrt);
   2018 			return NULL;
   2019 		}
   2020 		nrt->rt_rmx = rt->rt_rmx;
   2021 		rtfree(rt);
   2022 		rt = nrt;
   2023 	}
   2024 	error = rt_timer_add(rt, icmp6_mtudisc_timeout,
   2025 			icmp6_mtudisc_timeout_q);
   2026 	if (error) {
   2027 		rtfree(rt);
   2028 		return NULL;
   2029 	}
   2030 
   2031 	return rt;	/* caller need to call rtfree() */
   2032 }
   2033 
   2034 static void
   2035 icmp6_mtudisc_timeout(rt, r)
   2036 	struct rtentry *rt;
   2037 	struct rttimer *r;
   2038 {
   2039 	if (rt == NULL)
   2040 		panic("icmp6_mtudisc_timeout: bad route to timeout");
   2041 	if ((rt->rt_flags & (RTF_DYNAMIC | RTF_HOST)) ==
   2042 	    (RTF_DYNAMIC | RTF_HOST)) {
   2043 		rtrequest((int) RTM_DELETE, (struct sockaddr *)rt_key(rt),
   2044 		    rt->rt_gateway, rt_mask(rt), rt->rt_flags, 0);
   2045 	} else {
   2046 		if ((rt->rt_rmx.rmx_locks & RTV_MTU) == 0) {
   2047 			rt->rt_rmx.rmx_mtu = 0;
   2048 		}
   2049 	}
   2050 }
   2051 
   2052 #include <vm/vm.h>
   2053 #include <sys/sysctl.h>
   2054 int
   2055 icmp6_sysctl(name, namelen, oldp, oldlenp, newp, newlen)
   2056 	int *name;
   2057 	u_int namelen;
   2058 	void *oldp;
   2059 	size_t *oldlenp;
   2060 	void *newp;
   2061 	size_t newlen;
   2062 {
   2063 
   2064 	/* All sysctl names at this level are terminal. */
   2065 	if (namelen != 1)
   2066 		return ENOTDIR;
   2067 
   2068 	switch (name[0]) {
   2069 
   2070 	case ICMPV6CTL_REDIRACCEPT:
   2071 		return sysctl_int(oldp, oldlenp, newp, newlen,
   2072 				&icmp6_rediraccept);
   2073 	case ICMPV6CTL_REDIRTIMEOUT:
   2074 		return sysctl_int(oldp, oldlenp, newp, newlen,
   2075 				&icmp6_redirtimeout);
   2076 	case ICMPV6CTL_STATS:
   2077 		return sysctl_rdstruct(oldp, oldlenp, newp,
   2078 				&icmp6stat, sizeof(icmp6stat));
   2079 	case ICMPV6CTL_ERRRATELIMIT:
   2080 		return sysctl_int(oldp, oldlenp, newp, newlen,
   2081 				  &icmp6errratelim);
   2082 	case ICMPV6CTL_ND6_PRUNE:
   2083 		return sysctl_int(oldp, oldlenp, newp, newlen, &nd6_prune);
   2084 	case ICMPV6CTL_ND6_DELAY:
   2085 		return sysctl_int(oldp, oldlenp, newp, newlen, &nd6_delay);
   2086 	case ICMPV6CTL_ND6_UMAXTRIES:
   2087 		return sysctl_int(oldp, oldlenp, newp, newlen, &nd6_umaxtries);
   2088 	case ICMPV6CTL_ND6_MMAXTRIES:
   2089 		return sysctl_int(oldp, oldlenp, newp, newlen, &nd6_mmaxtries);
   2090 	case ICMPV6CTL_ND6_USELOOPBACK:
   2091 		return sysctl_int(oldp, oldlenp, newp, newlen,
   2092 				&nd6_useloopback);
   2093 	case ICMPV6CTL_ND6_PROXYALL:
   2094 		return sysctl_int(oldp, oldlenp, newp, newlen, &nd6_proxyall);
   2095 	case ICMPV6CTL_NODEINFO:
   2096 		return sysctl_int(oldp, oldlenp, newp, newlen, &icmp6_nodeinfo);
   2097 	default:
   2098 		return ENOPROTOOPT;
   2099 	}
   2100 	/* NOTREACHED */
   2101 }
   2102