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in6_ifattach.c revision 1.30.4.2
      1 /*	$NetBSD: in6_ifattach.c,v 1.30.4.2 2003/08/05 12:50:09 msaitoh Exp $	*/
      2 /*	$KAME: in6_ifattach.c,v 1.56 2000/05/05 06:54:33 itojun Exp $	*/
      3 
      4 /*
      5  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
      6  * All rights reserved.
      7  *
      8  * Redistribution and use in source and binary forms, with or without
      9  * modification, are permitted provided that the following conditions
     10  * are met:
     11  * 1. Redistributions of source code must retain the above copyright
     12  *    notice, this list of conditions and the following disclaimer.
     13  * 2. Redistributions in binary form must reproduce the above copyright
     14  *    notice, this list of conditions and the following disclaimer in the
     15  *    documentation and/or other materials provided with the distribution.
     16  * 3. Neither the name of the project nor the names of its contributors
     17  *    may be used to endorse or promote products derived from this software
     18  *    without specific prior written permission.
     19  *
     20  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
     21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
     24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     30  * SUCH DAMAGE.
     31  */
     32 
     33 #include <sys/param.h>
     34 #include <sys/systm.h>
     35 #include <sys/malloc.h>
     36 #include <sys/socket.h>
     37 #include <sys/sockio.h>
     38 #include <sys/kernel.h>
     39 #include <sys/md5.h>
     40 
     41 #include <net/if.h>
     42 #include <net/if_dl.h>
     43 #include <net/if_types.h>
     44 #include <net/route.h>
     45 
     46 #include <netinet/in.h>
     47 #include <netinet/in_var.h>
     48 
     49 #include <netinet/ip6.h>
     50 #include <netinet6/ip6_var.h>
     51 #include <netinet6/in6_ifattach.h>
     52 #include <netinet6/ip6_var.h>
     53 #include <netinet6/nd6.h>
     54 #include <netinet6/ip6_mroute.h>
     55 
     56 #include <net/net_osdep.h>
     57 
     58 struct in6_ifstat **in6_ifstat = NULL;
     59 struct icmp6_ifstat **icmp6_ifstat = NULL;
     60 size_t in6_ifstatmax = 0;
     61 size_t icmp6_ifstatmax = 0;
     62 unsigned long in6_maxmtu = 0;
     63 
     64 static int get_rand_ifid __P((struct ifnet *, struct in6_addr *));
     65 static int get_hw_ifid __P((struct ifnet *, struct in6_addr *));
     66 static int get_ifid __P((struct ifnet *, struct ifnet *, struct in6_addr *));
     67 static int in6_ifattach_addaddr __P((struct ifnet *, struct in6_ifaddr *));
     68 static int in6_ifattach_linklocal __P((struct ifnet *, struct ifnet *));
     69 static int in6_ifattach_loopback __P((struct ifnet *));
     70 
     71 #define EUI64_GBIT	0x01
     72 #define EUI64_UBIT	0x02
     73 #define EUI64_TO_IFID(in6)	do {(in6)->s6_addr[8] ^= EUI64_UBIT; } while (0)
     74 #define EUI64_GROUP(in6)	((in6)->s6_addr[8] & EUI64_GBIT)
     75 #define EUI64_INDIVIDUAL(in6)	(!EUI64_GROUP(in6))
     76 #define EUI64_LOCAL(in6)	((in6)->s6_addr[8] & EUI64_UBIT)
     77 #define EUI64_UNIVERSAL(in6)	(!EUI64_LOCAL(in6))
     78 
     79 #define IFID_LOCAL(in6)		(!EUI64_LOCAL(in6))
     80 #define IFID_UNIVERSAL(in6)	(!EUI64_UNIVERSAL(in6))
     81 
     82 /*
     83  * Generate a last-resort interface identifier, when the machine has no
     84  * IEEE802/EUI64 address sources.
     85  * The goal here is to get an interface identifier that is
     86  * (1) random enough and (2) does not change across reboot.
     87  * We currently use MD5(hostname) for it.
     88  */
     89 static int
     90 get_rand_ifid(ifp, in6)
     91 	struct ifnet *ifp;
     92 	struct in6_addr *in6;	/*upper 64bits are preserved */
     93 {
     94 	MD5_CTX ctxt;
     95 	u_int8_t digest[16];
     96 
     97 #if 0
     98 	/* we need at least several letters as seed for ifid */
     99 	if (hostnamelen < 3)
    100 		return -1;
    101 #endif
    102 
    103 	/* generate 8 bytes of pseudo-random value. */
    104 	bzero(&ctxt, sizeof(ctxt));
    105 	MD5Init(&ctxt);
    106 	MD5Update(&ctxt, hostname, hostnamelen);
    107 	MD5Final(digest, &ctxt);
    108 
    109 	/* assumes sizeof(digest) > sizeof(ifid) */
    110 	bcopy(digest, &in6->s6_addr[8], 8);
    111 
    112 	/* make sure to set "u" bit to local, and "g" bit to individual. */
    113 	in6->s6_addr[8] &= ~EUI64_GBIT;	/* g bit to "individual" */
    114 	in6->s6_addr[8] |= EUI64_UBIT;	/* u bit to "local" */
    115 
    116 	/* convert EUI64 into IPv6 interface identifier */
    117 	EUI64_TO_IFID(in6);
    118 
    119 	return 0;
    120 }
    121 
    122 /*
    123  * Get interface identifier for the specified interface.
    124  * XXX assumes single sockaddr_dl (AF_LINK address) per an interface
    125  */
    126 static int
    127 get_hw_ifid(ifp, in6)
    128 	struct ifnet *ifp;
    129 	struct in6_addr *in6;	/*upper 64bits are preserved */
    130 {
    131 	struct ifaddr *ifa;
    132 	struct sockaddr_dl *sdl;
    133 	u_int8_t *addr;
    134 	size_t addrlen;
    135 	static u_int8_t allzero[8] = { 0, 0, 0, 0, 0, 0, 0, 0 };
    136 	static u_int8_t allone[8] =
    137 		{ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
    138 
    139 	for (ifa = ifp->if_addrlist.tqh_first;
    140 	     ifa;
    141 	     ifa = ifa->ifa_list.tqe_next)
    142 	{
    143 		if (ifa->ifa_addr->sa_family != AF_LINK)
    144 			continue;
    145 		sdl = (struct sockaddr_dl *)ifa->ifa_addr;
    146 		if (sdl == NULL)
    147 			continue;
    148 		if (sdl->sdl_alen == 0)
    149 			continue;
    150 
    151 		goto found;
    152 	}
    153 
    154 	return -1;
    155 
    156 found:
    157 	addr = LLADDR(sdl);
    158 	addrlen = sdl->sdl_alen;
    159 
    160 	/* get EUI64 */
    161 	switch (ifp->if_type) {
    162 	case IFT_ETHER:
    163 	case IFT_FDDI:
    164 	case IFT_ATM:
    165 		/* IEEE802/EUI64 cases - what others? */
    166 
    167 		/* look at IEEE802/EUI64 only */
    168 		if (addrlen != 8 && addrlen != 6)
    169 			return -1;
    170 
    171 		/*
    172 		 * check for invalid MAC address - on bsdi, we see it a lot
    173 		 * since wildboar configures all-zero MAC on pccard before
    174 		 * card insertion.
    175 		 */
    176 		if (bcmp(addr, allzero, addrlen) == 0)
    177 			return -1;
    178 		if (bcmp(addr, allone, addrlen) == 0)
    179 			return -1;
    180 
    181 		/* make EUI64 address */
    182 		if (addrlen == 8)
    183 			bcopy(addr, &in6->s6_addr[8], 8);
    184 		else if (addrlen == 6) {
    185 			in6->s6_addr[8] = addr[0];
    186 			in6->s6_addr[9] = addr[1];
    187 			in6->s6_addr[10] = addr[2];
    188 			in6->s6_addr[11] = 0xff;
    189 			in6->s6_addr[12] = 0xfe;
    190 			in6->s6_addr[13] = addr[3];
    191 			in6->s6_addr[14] = addr[4];
    192 			in6->s6_addr[15] = addr[5];
    193 		}
    194 		break;
    195 
    196 	case IFT_ARCNET:
    197 		if (addrlen != 1)
    198 			return -1;
    199 		if (!addr[0])
    200 			return -1;
    201 
    202 		bzero(&in6->s6_addr[8], 8);
    203 		in6->s6_addr[15] = addr[0];
    204 
    205 		/*
    206 		 * due to insufficient bitwidth, we mark it local.
    207 		 */
    208 		in6->s6_addr[8] &= ~EUI64_GBIT;	/* g bit to "individual" */
    209 		in6->s6_addr[8] |= EUI64_UBIT;	/* u bit to "local" */
    210 		break;
    211 
    212 	case IFT_GIF:
    213 #ifdef IFT_STF
    214 	case IFT_STF:
    215 #endif
    216 		/*
    217 		 * mech-06 says: "SHOULD use IPv4 address as ifid source".
    218 		 * however, IPv4 address is not very suitable as unique
    219 		 * identifier source (can be renumbered).
    220 		 * we don't do this.
    221 		 */
    222 		return -1;
    223 
    224 	default:
    225 		return -1;
    226 	}
    227 
    228 	/* sanity check: g bit must not indicate "group" */
    229 	if (EUI64_GROUP(in6))
    230 		return -1;
    231 
    232 	/* convert EUI64 into IPv6 interface identifier */
    233 	EUI64_TO_IFID(in6);
    234 
    235 	/*
    236 	 * sanity check: ifid must not be all zero, avoid conflict with
    237 	 * subnet router anycast
    238 	 */
    239 	if ((in6->s6_addr[8] & ~(EUI64_GBIT | EUI64_UBIT)) == 0x00 &&
    240 	    bcmp(&in6->s6_addr[9], allzero, 7) == 0) {
    241 		return -1;
    242 	}
    243 
    244 	return 0;
    245 }
    246 
    247 /*
    248  * Get interface identifier for the specified interface.  If it is not
    249  * available on ifp0, borrow interface identifier from other information
    250  * sources.
    251  */
    252 static int
    253 get_ifid(ifp0, altifp, in6)
    254 	struct ifnet *ifp0;
    255 	struct ifnet *altifp;	/*secondary EUI64 source*/
    256 	struct in6_addr *in6;
    257 {
    258 	struct ifnet *ifp;
    259 
    260 	/* first, try to get it from the interface itself */
    261 	if (get_hw_ifid(ifp0, in6) == 0) {
    262 #ifdef ND6_DEBUG
    263 		printf("%s: got interface identifier from itself\n",
    264 		    if_name(ifp0));
    265 #endif
    266 		goto success;
    267 	}
    268 
    269 	/* try secondary EUI64 source. this basically is for ATM PVC */
    270 	if (altifp && get_hw_ifid(altifp, in6) == 0) {
    271 #ifdef ND6_DEBUG
    272 		printf("%s: got interface identifier from %s\n",
    273 		    if_name(ifp0), ifname(altifp));
    274 #endif
    275 		goto success;
    276 	}
    277 
    278 	/* next, try to get it from some other hardware interface */
    279 	for (ifp = ifnet.tqh_first; ifp; ifp = ifp->if_list.tqe_next)
    280 	{
    281 		if (ifp == ifp0)
    282 			continue;
    283 		if (get_hw_ifid(ifp, in6) != 0)
    284 			continue;
    285 
    286 		/*
    287 		 * to borrow ifid from other interface, ifid needs to be
    288 		 * globally unique
    289 		 */
    290 		if (IFID_UNIVERSAL(in6)) {
    291 
    292 #ifdef ND6_DEBUG
    293 			printf("%s: borrow interface identifier from %s\n",
    294 			    if_name(ifp0), if_name(ifp));
    295 #endif
    296 			goto success;
    297 		}
    298 	}
    299 
    300 	/* last resort: get from random number source */
    301 	if (get_rand_ifid(ifp, in6) == 0) {
    302 #ifdef ND6_DEBUG
    303 		printf("%s: interface identifier generated by random number\n",
    304 		    if_name(ifp0));
    305 #endif
    306 		goto success;
    307 	}
    308 
    309 	printf("%s: failed to get interface identifier", if_name(ifp0));
    310 	return -1;
    311 
    312 success:
    313 #ifdef ND6_DEBUG
    314 	printf("%s: ifid: "
    315 		"%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x\n",
    316 		if_name(ifp0),
    317 		in6->s6_addr[8], in6->s6_addr[9],
    318 		in6->s6_addr[10], in6->s6_addr[11],
    319 		in6->s6_addr[12], in6->s6_addr[13],
    320 		in6->s6_addr[14], in6->s6_addr[15]);
    321 #endif
    322 	return 0;
    323 }
    324 
    325 /*
    326  * configure IPv6 interface address.  XXX code duplicated with in.c
    327  */
    328 static int
    329 in6_ifattach_addaddr(ifp, ia)
    330 	struct ifnet *ifp;
    331 	struct in6_ifaddr *ia;
    332 {
    333 	struct in6_ifaddr *oia;
    334 	struct ifaddr *ifa;
    335 	int error;
    336 	int rtflag;
    337 	struct in6_addr llsol;
    338 
    339 	/*
    340 	 * initialize if_addrlist, if we are the very first one
    341 	 */
    342 	ifa = TAILQ_FIRST(&ifp->if_addrlist);
    343 	if (ifa == NULL) {
    344 		TAILQ_INIT(&ifp->if_addrlist);
    345 	}
    346 
    347 	/*
    348 	 * link the interface address to global list
    349 	 */
    350 	TAILQ_INSERT_TAIL(&ifp->if_addrlist, (struct ifaddr *)ia, ifa_list);
    351 	IFAREF(&ia->ia_ifa);
    352 
    353 	/*
    354 	 * Also link into the IPv6 address chain beginning with in6_ifaddr.
    355 	 * kazu opposed it, but itojun & jinmei wanted.
    356 	 */
    357 	if ((oia = in6_ifaddr) != NULL) {
    358 		for (; oia->ia_next; oia = oia->ia_next)
    359 			continue;
    360 		oia->ia_next = ia;
    361 	} else
    362 		in6_ifaddr = ia;
    363 	IFAREF(&ia->ia_ifa);
    364 
    365 	/*
    366 	 * give the interface a chance to initialize, in case this
    367 	 * is the first address to be added.
    368 	 */
    369 	if (ifp->if_ioctl != NULL) {
    370 		int s;
    371 		s = splimp();
    372 		error = (*ifp->if_ioctl)(ifp, SIOCSIFADDR, (caddr_t)ia);
    373 		splx(s);
    374 	} else
    375 		error = 0;
    376 	if (error) {
    377 		switch (error) {
    378 		case EAFNOSUPPORT:
    379 			printf("%s: IPv6 not supported\n", if_name(ifp));
    380 			break;
    381 		default:
    382 			printf("%s: SIOCSIFADDR error %d\n", if_name(ifp),
    383 			    error);
    384 			break;
    385 		}
    386 
    387 		/* undo changes */
    388 		TAILQ_REMOVE(&ifp->if_addrlist, (struct ifaddr *)ia, ifa_list);
    389 		IFAFREE(&ia->ia_ifa);
    390 		if (oia)
    391 			oia->ia_next = ia->ia_next;
    392 		else
    393 			in6_ifaddr = ia->ia_next;
    394 		IFAFREE(&ia->ia_ifa);
    395 		return -1;
    396 	}
    397 
    398 	/* configure link-layer address resolution */
    399 	rtflag = 0;
    400 	if (IN6_ARE_ADDR_EQUAL(&ia->ia_prefixmask.sin6_addr, &in6mask128))
    401 		rtflag = RTF_HOST;
    402 	else {
    403 		switch (ifp->if_type) {
    404 		case IFT_LOOP:
    405 #ifdef IFT_STF
    406 		case IFT_STF:
    407 #endif
    408 			rtflag = 0;
    409 			break;
    410 		default:
    411 			ia->ia_ifa.ifa_rtrequest = nd6_rtrequest;
    412 			ia->ia_ifa.ifa_flags |= RTF_CLONING;
    413 			rtflag = RTF_CLONING;
    414 			break;
    415 		}
    416 	}
    417 
    418 	/* add route to the interface. */
    419 	rtrequest(RTM_ADD,
    420 		  (struct sockaddr *)&ia->ia_addr,
    421 		  (struct sockaddr *)&ia->ia_addr,
    422 		  (struct sockaddr *)&ia->ia_prefixmask,
    423 		  RTF_UP | rtflag,
    424 		  (struct rtentry **)0);
    425 	ia->ia_flags |= IFA_ROUTE;
    426 
    427 	if ((rtflag & RTF_CLONING) != 0 &&
    428 	    (ifp->if_flags & IFF_MULTICAST) != 0) {
    429 		/* Restore saved multicast addresses (if any). */
    430 		in6_restoremkludge(ia, ifp);
    431 
    432 		/*
    433 		 * join solicited multicast address
    434 		 */
    435 		bzero(&llsol, sizeof(llsol));
    436 		llsol.s6_addr16[0] = htons(0xff02);
    437 		llsol.s6_addr16[1] = htons(ifp->if_index);
    438 		llsol.s6_addr32[1] = 0;
    439 		llsol.s6_addr32[2] = htonl(1);
    440 		llsol.s6_addr32[3] = ia->ia_addr.sin6_addr.s6_addr32[3];
    441 		llsol.s6_addr8[12] = 0xff;
    442 		(void)in6_addmulti(&llsol, ifp, &error);
    443 
    444 		/* XXX should we run DAD on other interface types? */
    445 		switch (ifp->if_type) {
    446 #if 1
    447 		case IFT_ARCNET:
    448 		case IFT_ETHER:
    449 		case IFT_FDDI:
    450 #else
    451 		default:
    452 #endif
    453 			/* mark the address TENTATIVE, if needed. */
    454 			ia->ia6_flags |= IN6_IFF_TENTATIVE;
    455 			/* nd6_dad_start() will be called in in6_if_up */
    456 		}
    457 	}
    458 
    459 	return 0;
    460 }
    461 
    462 static int
    463 in6_ifattach_linklocal(ifp, altifp)
    464 	struct ifnet *ifp;
    465 	struct ifnet *altifp;	/*secondary EUI64 source*/
    466 {
    467 	struct in6_ifaddr *ia;
    468 
    469 	/*
    470 	 * configure link-local address
    471 	 */
    472 	ia = (struct in6_ifaddr *)malloc(sizeof(*ia), M_IFADDR, M_WAITOK);
    473 	bzero((caddr_t)ia, sizeof(*ia));
    474 	ia->ia_ifa.ifa_addr = (struct sockaddr *)&ia->ia_addr;
    475 	if (ifp->if_flags & IFF_POINTOPOINT)
    476 		ia->ia_ifa.ifa_dstaddr = (struct sockaddr *)&ia->ia_dstaddr;
    477 	else
    478 		ia->ia_ifa.ifa_dstaddr = NULL;
    479 	ia->ia_ifa.ifa_netmask = (struct sockaddr *)&ia->ia_prefixmask;
    480 	ia->ia_ifp = ifp;
    481 
    482 	bzero(&ia->ia_prefixmask, sizeof(ia->ia_prefixmask));
    483 	ia->ia_prefixmask.sin6_len = sizeof(struct sockaddr_in6);
    484 	ia->ia_prefixmask.sin6_family = AF_INET6;
    485 	ia->ia_prefixmask.sin6_addr = in6mask64;
    486 
    487 	/* just in case */
    488 	bzero(&ia->ia_dstaddr, sizeof(ia->ia_dstaddr));
    489 	ia->ia_dstaddr.sin6_len = sizeof(struct sockaddr_in6);
    490 	ia->ia_dstaddr.sin6_family = AF_INET6;
    491 
    492 	bzero(&ia->ia_addr, sizeof(ia->ia_addr));
    493 	ia->ia_addr.sin6_len = sizeof(struct sockaddr_in6);
    494 	ia->ia_addr.sin6_family = AF_INET6;
    495 	ia->ia_addr.sin6_addr.s6_addr16[0] = htons(0xfe80);
    496 	ia->ia_addr.sin6_addr.s6_addr16[1] = htons(ifp->if_index);
    497 	ia->ia_addr.sin6_addr.s6_addr32[1] = 0;
    498 	if (ifp->if_flags & IFF_LOOPBACK) {
    499 		ia->ia_addr.sin6_addr.s6_addr32[2] = 0;
    500 		ia->ia_addr.sin6_addr.s6_addr32[3] = htonl(1);
    501 	} else {
    502 		if (get_ifid(ifp, altifp, &ia->ia_addr.sin6_addr) != 0) {
    503 #ifdef ND6_DEBUG
    504 			printf("%s: no ifid available\n", if_name(ifp));
    505 #endif
    506 			free(ia, M_IFADDR);
    507 			return -1;
    508 		}
    509 	}
    510 
    511 	ia->ia_ifa.ifa_metric = ifp->if_metric;
    512 
    513 	if (in6_ifattach_addaddr(ifp, ia) != 0) {
    514 		/* ia will be freed on failure */
    515 		return -1;
    516 	}
    517 
    518 	return 0;
    519 }
    520 
    521 static int
    522 in6_ifattach_loopback(ifp)
    523 	struct ifnet *ifp;	/* must be IFT_LOOP */
    524 {
    525 	struct in6_ifaddr *ia;
    526 
    527 	/*
    528 	 * configure link-local address
    529 	 */
    530 	ia = (struct in6_ifaddr *)malloc(sizeof(*ia), M_IFADDR, M_WAITOK);
    531 	bzero((caddr_t)ia, sizeof(*ia));
    532 	ia->ia_ifa.ifa_addr = (struct sockaddr *)&ia->ia_addr;
    533 	ia->ia_ifa.ifa_dstaddr = (struct sockaddr *)&ia->ia_dstaddr;
    534 	ia->ia_ifa.ifa_netmask = (struct sockaddr *)&ia->ia_prefixmask;
    535 	ia->ia_ifp = ifp;
    536 
    537 	bzero(&ia->ia_prefixmask, sizeof(ia->ia_prefixmask));
    538 	ia->ia_prefixmask.sin6_len = sizeof(struct sockaddr_in6);
    539 	ia->ia_prefixmask.sin6_family = AF_INET6;
    540 	ia->ia_prefixmask.sin6_addr = in6mask128;
    541 
    542 	/*
    543 	 * Always initialize ia_dstaddr (= broadcast address) to loopback
    544 	 * address, to make getifaddr happier.
    545 	 *
    546 	 * For BSDI, it is mandatory.  The BSDI version of
    547 	 * ifa_ifwithroute() rejects to add a route to the loopback
    548 	 * interface.  Even for other systems, loopback looks somewhat
    549 	 * special.
    550 	 */
    551 	bzero(&ia->ia_dstaddr, sizeof(ia->ia_dstaddr));
    552 	ia->ia_dstaddr.sin6_len = sizeof(struct sockaddr_in6);
    553 	ia->ia_dstaddr.sin6_family = AF_INET6;
    554 	ia->ia_dstaddr.sin6_addr = in6addr_loopback;
    555 
    556 	bzero(&ia->ia_addr, sizeof(ia->ia_addr));
    557 	ia->ia_addr.sin6_len = sizeof(struct sockaddr_in6);
    558 	ia->ia_addr.sin6_family = AF_INET6;
    559 	ia->ia_addr.sin6_addr = in6addr_loopback;
    560 
    561 	ia->ia_ifa.ifa_metric = ifp->if_metric;
    562 
    563 	if (in6_ifattach_addaddr(ifp, ia) != 0) {
    564 		/* ia will be freed on failure */
    565 		return -1;
    566 	}
    567 
    568 	return 0;
    569 }
    570 
    571 /*
    572  * XXX multiple loopback interface needs more care.  for instance,
    573  * nodelocal address needs to be configured onto only one of them.
    574  * XXX multiple link-local address case
    575  */
    576 void
    577 in6_ifattach(ifp, altifp)
    578 	struct ifnet *ifp;
    579 	struct ifnet *altifp;	/* secondary EUI64 source */
    580 {
    581 	static size_t if_indexlim = 8;
    582 	struct sockaddr_in6 mltaddr;
    583 	struct sockaddr_in6 mltmask;
    584 	struct sockaddr_in6 gate;
    585 	struct sockaddr_in6 mask;
    586 	struct in6_ifaddr *ia;
    587 	struct in6_addr in6;
    588 
    589 	/*
    590 	 * We have some arrays that should be indexed by if_index.
    591 	 * since if_index will grow dynamically, they should grow too.
    592 	 *	struct in6_ifstat **in6_ifstat
    593 	 *	struct icmp6_ifstat **icmp6_ifstat
    594 	 */
    595 	if (in6_ifstat == NULL || icmp6_ifstat == NULL ||
    596 	    if_index >= if_indexlim) {
    597 		size_t n;
    598 		caddr_t q;
    599 		size_t olim;
    600 
    601 		olim = if_indexlim;
    602 		while (if_index >= if_indexlim)
    603 			if_indexlim <<= 1;
    604 
    605 		/* grow in6_ifstat */
    606 		n = if_indexlim * sizeof(struct in6_ifstat *);
    607 		q = (caddr_t)malloc(n, M_IFADDR, M_WAITOK);
    608 		bzero(q, n);
    609 		if (in6_ifstat) {
    610 			bcopy((caddr_t)in6_ifstat, q,
    611 				olim * sizeof(struct in6_ifstat *));
    612 			free((caddr_t)in6_ifstat, M_IFADDR);
    613 		}
    614 		in6_ifstat = (struct in6_ifstat **)q;
    615 		in6_ifstatmax = if_indexlim;
    616 
    617 		/* grow icmp6_ifstat */
    618 		n = if_indexlim * sizeof(struct icmp6_ifstat *);
    619 		q = (caddr_t)malloc(n, M_IFADDR, M_WAITOK);
    620 		bzero(q, n);
    621 		if (icmp6_ifstat) {
    622 			bcopy((caddr_t)icmp6_ifstat, q,
    623 				olim * sizeof(struct icmp6_ifstat *));
    624 			free((caddr_t)icmp6_ifstat, M_IFADDR);
    625 		}
    626 		icmp6_ifstat = (struct icmp6_ifstat **)q;
    627 		icmp6_ifstatmax = if_indexlim;
    628 	}
    629 
    630 	/*
    631 	 * quirks based on interface type
    632 	 */
    633 	switch (ifp->if_type) {
    634 #ifdef IFT_STF
    635 	case IFT_STF:
    636 		/*
    637 		 * 6to4 interface is a very speical kind of beast.
    638 		 * no multicast, no linklocal (based on 03 draft).
    639 		 */
    640 		goto statinit;
    641 #endif
    642 	default:
    643 		break;
    644 	}
    645 
    646 	/*
    647 	 * usually, we require multicast capability to the interface
    648 	 */
    649 	if ((ifp->if_flags & IFF_MULTICAST) == 0) {
    650 		printf("%s: not multicast capable, IPv6 not enabled\n",
    651 		    if_name(ifp));
    652 		return;
    653 	}
    654 
    655 	/*
    656 	 * assign link-local address, if there's none
    657 	 */
    658 	ia = in6ifa_ifpforlinklocal(ifp, 0);
    659 	if (ia == NULL) {
    660 		if (in6_ifattach_linklocal(ifp, altifp) != 0)
    661 			return;
    662 		ia = in6ifa_ifpforlinklocal(ifp, 0);
    663 
    664 		if (ia == NULL) {
    665 			printf("%s: failed to add link-local address",
    666 			    if_name(ifp));
    667 
    668 			/* we can't initialize multicasts without link-local */
    669 			goto statinit;
    670 		}
    671 	}
    672 
    673 	if (ifp->if_flags & IFF_POINTOPOINT) {
    674 		/*
    675 		 * route local address to loopback
    676 		 */
    677 		bzero(&gate, sizeof(gate));
    678 		gate.sin6_len = sizeof(struct sockaddr_in6);
    679 		gate.sin6_family = AF_INET6;
    680 		gate.sin6_addr = in6addr_loopback;
    681 		bzero(&mask, sizeof(mask));
    682 		mask.sin6_len = sizeof(struct sockaddr_in6);
    683 		mask.sin6_family = AF_INET6;
    684 		mask.sin6_addr = in6mask64;
    685 		rtrequest(RTM_ADD,
    686 			  (struct sockaddr *)&ia->ia_addr,
    687 			  (struct sockaddr *)&gate,
    688 			  (struct sockaddr *)&mask,
    689 			  RTF_UP|RTF_HOST,
    690 			  (struct rtentry **)0);
    691 	}
    692 
    693 	/*
    694 	 * assign loopback address for loopback interface
    695 	 * XXX multiple loopback interface case
    696 	 */
    697 	in6 = in6addr_loopback;
    698 	if (ifp->if_flags & IFF_LOOPBACK) {
    699 		if (in6ifa_ifpwithaddr(ifp, &in6) == NULL) {
    700 			if (in6_ifattach_loopback(ifp) != 0)
    701 				return;
    702 		}
    703 	}
    704 
    705 #ifdef DIAGNOSTIC
    706 	if (!ia) {
    707 		panic("ia == NULL in in6_ifattach");
    708 		/*NOTREACHED*/
    709 	}
    710 #endif
    711 
    712 	/*
    713 	 * join multicast
    714 	 */
    715 	if (ifp->if_flags & IFF_MULTICAST) {
    716 		int error;	/* not used */
    717 		struct in6_multi *in6m;
    718 
    719 		/* Restore saved multicast addresses (if any). */
    720 		in6_restoremkludge(ia, ifp);
    721 
    722 		bzero(&mltmask, sizeof(mltmask));
    723 		mltmask.sin6_len = sizeof(struct sockaddr_in6);
    724 		mltmask.sin6_family = AF_INET6;
    725 		mltmask.sin6_addr = in6mask32;
    726 
    727 		/*
    728 		 * join link-local all-nodes address
    729 		 */
    730 		bzero(&mltaddr, sizeof(mltaddr));
    731 		mltaddr.sin6_len = sizeof(struct sockaddr_in6);
    732 		mltaddr.sin6_family = AF_INET6;
    733 		mltaddr.sin6_addr = in6addr_linklocal_allnodes;
    734 		mltaddr.sin6_addr.s6_addr16[1] = htons(ifp->if_index);
    735 
    736 		IN6_LOOKUP_MULTI(mltaddr.sin6_addr, ifp, in6m);
    737 		if (in6m == NULL) {
    738 			rtrequest(RTM_ADD,
    739 				  (struct sockaddr *)&mltaddr,
    740 				  (struct sockaddr *)&ia->ia_addr,
    741 				  (struct sockaddr *)&mltmask,
    742 				  RTF_UP|RTF_CLONING,  /* xxx */
    743 				  (struct rtentry **)0);
    744 			(void)in6_addmulti(&mltaddr.sin6_addr, ifp, &error);
    745 		}
    746 
    747 		if (ifp->if_flags & IFF_LOOPBACK) {
    748 			in6 = in6addr_loopback;
    749 			ia = in6ifa_ifpwithaddr(ifp, &in6);
    750 			/*
    751 			 * join node-local all-nodes address, on loopback
    752 			 */
    753 			mltaddr.sin6_addr = in6addr_nodelocal_allnodes;
    754 
    755 			IN6_LOOKUP_MULTI(mltaddr.sin6_addr, ifp, in6m);
    756 			if (in6m == NULL && ia != NULL) {
    757 				rtrequest(RTM_ADD,
    758 					  (struct sockaddr *)&mltaddr,
    759 					  (struct sockaddr *)&ia->ia_addr,
    760 					  (struct sockaddr *)&mltmask,
    761 					  RTF_UP,
    762 					  (struct rtentry **)0);
    763 				(void)in6_addmulti(&mltaddr.sin6_addr, ifp, &error);
    764 			}
    765 		}
    766 	}
    767 
    768 statinit:;
    769 
    770 	/* update dynamically. */
    771 	if (in6_maxmtu < ifp->if_mtu)
    772 		in6_maxmtu = ifp->if_mtu;
    773 
    774 	if (in6_ifstat[ifp->if_index] == NULL) {
    775 		in6_ifstat[ifp->if_index] = (struct in6_ifstat *)
    776 			malloc(sizeof(struct in6_ifstat), M_IFADDR, M_WAITOK);
    777 		bzero(in6_ifstat[ifp->if_index], sizeof(struct in6_ifstat));
    778 	}
    779 	if (icmp6_ifstat[ifp->if_index] == NULL) {
    780 		icmp6_ifstat[ifp->if_index] = (struct icmp6_ifstat *)
    781 			malloc(sizeof(struct icmp6_ifstat), M_IFADDR, M_WAITOK);
    782 		bzero(icmp6_ifstat[ifp->if_index], sizeof(struct icmp6_ifstat));
    783 	}
    784 
    785 	/* initialize NDP variables */
    786 	nd6_ifattach(ifp);
    787 }
    788 
    789 /*
    790  * NOTE: in6_ifdetach() does not support loopback if at this moment.
    791  */
    792 void
    793 in6_ifdetach(ifp)
    794 	struct ifnet *ifp;
    795 {
    796 	struct in6_ifaddr *ia, *oia;
    797 	struct ifaddr *ifa, *next;
    798 	struct rtentry *rt;
    799 	short rtflags;
    800 	struct sockaddr_in6 sin6;
    801 
    802 	/* nuke prefix list.  this may try to remove some of ifaddrs as well */
    803 	in6_purgeprefix(ifp);
    804 
    805 	/* remove ip6_mrouter stuff */
    806 	ip6_mrouter_detach(ifp);
    807 
    808 	/* remove neighbor management table */
    809 	nd6_purge(ifp);
    810 
    811 	/* nuke any of IPv6 addresses we have */
    812 	for (ifa = ifp->if_addrlist.tqh_first; ifa; ifa = next)
    813 	{
    814 		next = ifa->ifa_list.tqe_next;
    815 		if (ifa->ifa_addr->sa_family != AF_INET6)
    816 			continue;
    817 		in6_purgeaddr(ifa, ifp);
    818 	}
    819 
    820 	/* undo everything done by in6_ifattach(), just in case */
    821 	for (ifa = ifp->if_addrlist.tqh_first; ifa; ifa = next)
    822 	{
    823 		next = ifa->ifa_list.tqe_next;
    824 
    825 
    826 		if (ifa->ifa_addr->sa_family != AF_INET6
    827 		 || !IN6_IS_ADDR_LINKLOCAL(&satosin6(&ifa->ifa_addr)->sin6_addr)) {
    828 			continue;
    829 		}
    830 
    831 		ia = (struct in6_ifaddr *)ifa;
    832 
    833 		/* remove from the routing table */
    834 		if ((ia->ia_flags & IFA_ROUTE)
    835 		 && (rt = rtalloc1((struct sockaddr *)&ia->ia_addr, 0))) {
    836 			rtflags = rt->rt_flags;
    837 			rtfree(rt);
    838 			rtrequest(RTM_DELETE,
    839 				(struct sockaddr *)&ia->ia_addr,
    840 				(struct sockaddr *)&ia->ia_addr,
    841 				(struct sockaddr *)&ia->ia_prefixmask,
    842 				rtflags, (struct rtentry **)0);
    843 		}
    844 
    845 		/* remove from the linked list */
    846 		TAILQ_REMOVE(&ifp->if_addrlist, (struct ifaddr *)ia, ifa_list);
    847 		IFAFREE(&ia->ia_ifa);
    848 
    849 		/* also remove from the IPv6 address chain(itojun&jinmei) */
    850 		oia = ia;
    851 		if (oia == (ia = in6_ifaddr))
    852 			in6_ifaddr = ia->ia_next;
    853 		else {
    854 			while (ia->ia_next && (ia->ia_next != oia))
    855 				ia = ia->ia_next;
    856 			if (ia->ia_next)
    857 				ia->ia_next = oia->ia_next;
    858 #ifdef ND6_DEBUG
    859 			else
    860 				printf("%s: didn't unlink in6ifaddr from "
    861 				    "list\n", if_name(ifp));
    862 #endif
    863 		}
    864 
    865 		IFAFREE(&oia->ia_ifa);
    866 	}
    867 
    868 	/* cleanup multicast address kludge table, if there is any */
    869 	in6_purgemkludge(ifp);
    870 
    871 	/* remove neighbor management table */
    872 	nd6_purge(ifp);
    873 
    874 	/* remove route to link-local allnodes multicast (ff02::1) */
    875 	bzero(&sin6, sizeof(sin6));
    876 	sin6.sin6_len = sizeof(struct sockaddr_in6);
    877 	sin6.sin6_family = AF_INET6;
    878 	sin6.sin6_addr = in6addr_linklocal_allnodes;
    879 	sin6.sin6_addr.s6_addr16[1] = htons(ifp->if_index);
    880 	rt = rtalloc1((struct sockaddr *)&sin6, 0);
    881 	if (rt && rt->rt_ifp == ifp) {
    882 		rtrequest(RTM_DELETE, (struct sockaddr *)rt_key(rt),
    883 			rt->rt_gateway, rt_mask(rt), rt->rt_flags, 0);
    884 		rtfree(rt);
    885 	}
    886 }
    887