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in6_proto.c revision 1.79.16.1
      1 /*	$NetBSD: in6_proto.c,v 1.79.16.1 2008/02/22 02:53:33 keiichi Exp $	*/
      2 /*	$KAME: in6_proto.c,v 1.66 2000/10/10 15:35:47 itojun Exp $	*/
      3 
      4 /*
      5  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
      6  * All rights reserved.
      7  *
      8  * Redistribution and use in source and binary forms, with or without
      9  * modification, are permitted provided that the following conditions
     10  * are met:
     11  * 1. Redistributions of source code must retain the above copyright
     12  *    notice, this list of conditions and the following disclaimer.
     13  * 2. Redistributions in binary form must reproduce the above copyright
     14  *    notice, this list of conditions and the following disclaimer in the
     15  *    documentation and/or other materials provided with the distribution.
     16  * 3. Neither the name of the project nor the names of its contributors
     17  *    may be used to endorse or promote products derived from this software
     18  *    without specific prior written permission.
     19  *
     20  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
     21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
     24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     30  * SUCH DAMAGE.
     31  */
     32 
     33 /*
     34  * Copyright (c) 1982, 1986, 1993
     35  *	The Regents of the University of California.  All rights reserved.
     36  *
     37  * Redistribution and use in source and binary forms, with or without
     38  * modification, are permitted provided that the following conditions
     39  * are met:
     40  * 1. Redistributions of source code must retain the above copyright
     41  *    notice, this list of conditions and the following disclaimer.
     42  * 2. Redistributions in binary form must reproduce the above copyright
     43  *    notice, this list of conditions and the following disclaimer in the
     44  *    documentation and/or other materials provided with the distribution.
     45  * 3. Neither the name of the University nor the names of its contributors
     46  *    may be used to endorse or promote products derived from this software
     47  *    without specific prior written permission.
     48  *
     49  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     50  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     51  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     52  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     53  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     54  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     55  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     56  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     57  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     58  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     59  * SUCH DAMAGE.
     60  *
     61  *	@(#)in_proto.c	8.1 (Berkeley) 6/10/93
     62  */
     63 
     64 #include <sys/cdefs.h>
     65 __KERNEL_RCSID(0, "$NetBSD: in6_proto.c,v 1.79.16.1 2008/02/22 02:53:33 keiichi Exp $");
     66 
     67 #include "opt_inet.h"
     68 #include "opt_ipsec.h"
     69 #include "opt_iso.h"
     70 
     71 #include <sys/param.h>
     72 #include <sys/socket.h>
     73 #include <sys/protosw.h>
     74 #include <sys/kernel.h>
     75 #include <sys/domain.h>
     76 #include <sys/mbuf.h>
     77 
     78 #include <net/if.h>
     79 #include <net/radix.h>
     80 #include <net/route.h>
     81 
     82 #include <netinet/in.h>
     83 #include <netinet/in_systm.h>
     84 #include <netinet/in_var.h>
     85 #include <netinet/ip_encap.h>
     86 #include <netinet/ip.h>
     87 #include <netinet/ip_var.h>
     88 #include <netinet/in_pcb.h>
     89 #include <netinet/ip6.h>
     90 #include <netinet6/ip6_var.h>
     91 #include <netinet/icmp6.h>
     92 #include <netinet6/in6_pcb.h>
     93 
     94 #include <netinet/tcp.h>
     95 #include <netinet/tcp_fsm.h>
     96 #include <netinet/tcp_seq.h>
     97 #include <netinet/tcp_timer.h>
     98 #include <netinet/tcp_var.h>
     99 #include <netinet/tcpip.h>
    100 #include <netinet/tcp_debug.h>
    101 
    102 #include <netinet6/udp6.h>
    103 #include <netinet6/udp6_var.h>
    104 
    105 #include <netinet6/pim6_var.h>
    106 
    107 #include <netinet6/nd6.h>
    108 
    109 #ifdef IPSEC
    110 #include <netinet6/ipsec.h>
    111 #include <netinet6/ah.h>
    112 #ifdef IPSEC_ESP
    113 #include <netinet6/esp.h>
    114 #endif
    115 #include <netinet6/ipcomp.h>
    116 #endif /* IPSEC */
    117 
    118 #ifdef FAST_IPSEC
    119 #include <netipsec/ipsec.h>
    120 #include <netipsec/ipsec6.h>
    121 #include <netipsec/key.h>
    122 #endif /* FAST_IPSEC */
    123 
    124 
    125 #include "carp.h"
    126 #if NCARP > 0
    127 #include <netinet/ip_carp.h>
    128 #endif
    129 
    130 #include "etherip.h"
    131 #if NETHERIP > 1
    132 #include <netinet6/ip6_etherip.h>
    133 #endif
    134 
    135 #ifdef MOBILE_IPV6
    136 #include <netinet6/mip6_var.h>
    137 #endif /* MOBILE_IPV6 */
    138 
    139 #include <netinet6/ip6protosw.h>
    140 
    141 #include <net/net_osdep.h>
    142 
    143 #ifndef offsetof		/* XXX */
    144 #define	offsetof(type, member)	((size_t)(&((type *)0)->member))
    145 #endif
    146 
    147 /*
    148  * TCP/IP protocol family: IP6, ICMP6, UDP, TCP.
    149  */
    150 
    151 DOMAIN_DEFINE(inet6domain);	/* forward declare and add to link set */
    152 
    153 const struct ip6protosw inet6sw[] = {
    154 {	.pr_domain = &inet6domain,
    155 	.pr_protocol = IPPROTO_IPV6,
    156 	.pr_init = ip6_init,
    157 	.pr_slowtimo = frag6_slowtimo,
    158 	.pr_drain = frag6_drain,
    159 },
    160 {	.pr_type = SOCK_DGRAM,
    161 	.pr_domain = &inet6domain,
    162 	.pr_protocol = IPPROTO_UDP,
    163 	.pr_flags = PR_ATOMIC|PR_ADDR|PR_PURGEIF,
    164 	.pr_input = udp6_input,
    165 	.pr_ctlinput = udp6_ctlinput,
    166 	.pr_ctloutput = ip6_ctloutput,
    167 	.pr_usrreq = udp6_usrreq,
    168 	.pr_init = udp6_init,
    169 },
    170 {	.pr_type = SOCK_STREAM,
    171 	.pr_domain = &inet6domain,
    172 	.pr_protocol = IPPROTO_TCP,
    173 	.pr_flags = PR_CONNREQUIRED|PR_WANTRCVD|PR_LISTEN|PR_ABRTACPTDIS|PR_PURGEIF,
    174 	.pr_input = tcp6_input,
    175 	.pr_ctlinput = tcp6_ctlinput,
    176 	.pr_ctloutput = tcp_ctloutput,
    177 	.pr_usrreq = tcp_usrreq,
    178 #ifndef INET	/* don't call initialization and timeout routines twice */
    179 	.pr_init = tcp_init,
    180 	.pr_slowtimo = tcp_slowtimo,
    181 	.pr_drain = tcp_drain,
    182 #endif
    183 },
    184 {	.pr_type = SOCK_RAW,
    185 	.pr_domain = &inet6domain,
    186 	.pr_protocol = IPPROTO_RAW,
    187 	.pr_flags = PR_ATOMIC|PR_ADDR|PR_PURGEIF,
    188 	.pr_input = rip6_input,
    189 	.pr_output = rip6_output,
    190 	.pr_ctlinput = rip6_ctlinput,
    191 	.pr_ctloutput = rip6_ctloutput,
    192 	.pr_usrreq = rip6_usrreq,
    193 },
    194 #ifdef GATEWAY
    195 {	.pr_domain = &inet6domain,
    196 	.pr_protocol = IPPROTO_IPV6,
    197 	.pr_slowtimo = ip6flow_slowtimo,
    198 },
    199 #endif /* GATEWAY */
    200 {	.pr_type = SOCK_RAW,
    201 	.pr_domain = &inet6domain,
    202 	.pr_protocol = IPPROTO_ICMPV6,
    203 	.pr_flags = PR_ATOMIC|PR_ADDR|PR_LASTHDR,
    204 	.pr_input = icmp6_input,
    205 	.pr_output = rip6_output,
    206 	.pr_ctlinput = rip6_ctlinput,
    207 	.pr_ctloutput = icmp6_ctloutput,
    208 	.pr_usrreq = rip6_usrreq,
    209 	.pr_init = icmp6_init,
    210 },
    211 {	.pr_type = SOCK_RAW,
    212 	.pr_domain = &inet6domain,
    213 	.pr_protocol = IPPROTO_DSTOPTS,
    214 	.pr_flags = PR_ATOMIC|PR_ADDR,
    215 	.pr_input = dest6_input,
    216 },
    217 {	.pr_type = SOCK_RAW,
    218 	.pr_domain = &inet6domain,
    219 	.pr_protocol = IPPROTO_ROUTING,
    220 	.pr_flags = PR_ATOMIC|PR_ADDR,
    221 	.pr_input = route6_input,
    222 },
    223 {	.pr_type = SOCK_RAW,
    224 	.pr_domain = &inet6domain,
    225 	.pr_protocol = IPPROTO_FRAGMENT,
    226 	.pr_flags = PR_ATOMIC|PR_ADDR,
    227 	.pr_input = frag6_input,
    228 },
    229 #ifdef MOBILE_IPV6
    230 {
    231 	.pr_type = SOCK_RAW,
    232 	.pr_domain = &inet6domain,
    233 	.pr_protocol = IPPROTO_MH,
    234 	.pr_flags = PR_ATOMIC|PR_ADDR|PR_LASTHDR,
    235 	.pr_input = mip6_input,
    236 	.pr_ctloutput = rip6_ctloutput,
    237 	.pr_usrreq = rip6_usrreq,
    238 },
    239 #endif /* MOBILE_IPV6 */
    240 #ifdef IPSEC
    241 {	.pr_type = SOCK_RAW,
    242 	.pr_domain = &inet6domain,
    243 	.pr_protocol = IPPROTO_AH,
    244 	.pr_flags = PR_ATOMIC|PR_ADDR,
    245 	.pr_input = ah6_input,
    246 	.pr_ctlinput = ah6_ctlinput,
    247 },
    248 #ifdef IPSEC_ESP
    249 {	.pr_type = SOCK_RAW,
    250 	.pr_domain = &inet6domain,
    251 	.pr_protocol = IPPROTO_ESP,
    252 	.pr_flags = PR_ATOMIC|PR_ADDR,
    253 	.pr_input = esp6_input,
    254 	.pr_ctlinput = esp6_ctlinput,
    255 },
    256 #endif
    257 {	.pr_type = SOCK_RAW,
    258 	.pr_domain = &inet6domain,
    259 	.pr_protocol = IPPROTO_IPCOMP,
    260 	.pr_flags = PR_ATOMIC|PR_ADDR,
    261 	.pr_input = ipcomp6_input,
    262 },
    263 #endif /* IPSEC */
    264 #ifdef FAST_IPSEC
    265 {	.pr_type = SOCK_RAW,
    266 	.pr_domain = &inet6domain,
    267 	.pr_protocol = IPPROTO_AH,
    268 	.pr_flags = PR_ATOMIC|PR_ADDR,
    269 	.pr_input = ipsec6_common_input,
    270 	.pr_ctlinput = ah6_ctlinput,
    271 },
    272 {	.pr_type = SOCK_RAW,
    273 	.pr_domain = &inet6domain,
    274 	.pr_protocol = IPPROTO_ESP,
    275 	.pr_flags = PR_ATOMIC|PR_ADDR,
    276 	.pr_input = ipsec6_common_input,
    277 	.pr_ctlinput = esp6_ctlinput,
    278 },
    279 {	.pr_type = SOCK_RAW,
    280 	.pr_domain = &inet6domain,
    281 	.pr_protocol = IPPROTO_IPCOMP,
    282 	.pr_flags = PR_ATOMIC|PR_ADDR,
    283 	.pr_input = ipsec6_common_input,
    284 },
    285 #endif /* FAST_IPSEC */
    286 #ifdef INET
    287 {	.pr_type = SOCK_RAW,
    288 	.pr_domain = &inet6domain,
    289 	.pr_protocol = IPPROTO_IPV4,
    290 	.pr_flags = PR_ATOMIC|PR_ADDR|PR_LASTHDR,
    291 	.pr_input = encap6_input,
    292 	.pr_output = rip6_output,
    293 	.pr_ctlinput = encap6_ctlinput,
    294 	.pr_ctloutput = rip6_ctloutput,
    295 	.pr_usrreq = rip6_usrreq,
    296 	.pr_init = encap_init,
    297 },
    298 #endif
    299 {	.pr_type = SOCK_RAW,
    300 	.pr_domain = &inet6domain,
    301 	.pr_protocol = IPPROTO_IPV6,
    302 	.pr_flags = PR_ATOMIC|PR_ADDR|PR_LASTHDR,
    303 	.pr_input = encap6_input,
    304 	.pr_output = rip6_output,
    305 	.pr_ctlinput = encap6_ctlinput,
    306 	.pr_ctloutput = rip6_ctloutput,
    307 	.pr_usrreq = rip6_usrreq,
    308 	.pr_init = encap_init,
    309 },
    310 #if NETHERIP > 1
    311 {	.pr_type = SOCK_RAW,
    312 	.pr_domain = &inet6domain,
    313 	.pr_protocol = IPPROTO_ETHERIP,
    314 	.pr_flags = PR_ATOMIC|PR_ADDR|PR_LASTHDR,
    315 	.pr_input = ip6_etherip_input,
    316 	.pr_output = rip6_output,
    317 	.pr_ctlinput = rip6_ctlinput,
    318 	.pr_ctloutput = rip6_ctloutput,
    319 	.pr_usrreq = rip6_usrreq,
    320 },
    321 #endif
    322 #if NCARP > 0
    323 {	.pr_type = SOCK_RAW,
    324 	.pr_domain = &inet6domain,
    325 	.pr_protocol = IPPROTO_CARP,
    326 	.pr_flags = PR_ATOMIC|PR_ADDR,
    327 	.pr_input = carp6_proto_input,
    328 	.pr_output = rip6_output,
    329 	.pr_ctloutput = rip6_ctloutput,
    330 	.pr_usrreq = rip6_usrreq,
    331 },
    332 #endif /* NCARP */
    333 #ifdef ISO
    334 {	.pr_type = SOCK_RAW,
    335 	.pr_domain = &inet6domain,
    336 	.pr_protocol = IPPROTO_EON,
    337 	.pr_flags = PR_ATOMIC|PR_ADDR|PR_LASTHDR,
    338 	.pr_input = encap6_input,
    339 	.pr_output = rip6_output,
    340 	.pr_ctlinput = encap6_ctlinput,
    341 	.pr_ctloutput = rip6_ctloutput,
    342 	.pr_usrreq = rip6_usrreq,
    343 	/*XXX*/
    344 	.pr_init = encap_init,
    345 },
    346 #endif
    347 {	.pr_type = SOCK_RAW,
    348 	.pr_domain = &inet6domain,
    349 	.pr_protocol = IPPROTO_PIM,
    350 	.pr_flags = PR_ATOMIC|PR_ADDR|PR_LASTHDR,
    351 	.pr_input = pim6_input,
    352 	.pr_output = rip6_output,
    353 	.pr_ctloutput = rip6_ctloutput,
    354 	.pr_usrreq = rip6_usrreq,
    355 },
    356 /* raw wildcard */
    357 {	.pr_type = SOCK_RAW,
    358 	.pr_domain = &inet6domain,
    359 	.pr_flags = PR_ATOMIC|PR_ADDR|PR_LASTHDR,
    360 	.pr_input = rip6_input,
    361 	.pr_output = rip6_output,
    362 	.pr_ctloutput = rip6_ctloutput,
    363 	.pr_usrreq = rip6_usrreq,
    364 	.pr_init = rip6_init,
    365 },
    366 };
    367 
    368 POOL_INIT(sockaddr_in6_pool, sizeof(struct sockaddr_in6), 0, 0, 0,
    369     "sockaddr_in6_pool", NULL, IPL_NET);
    370 
    371 #ifdef MOBILE_IPV6
    372 /* To receive tunneled packet on mobile node or home agent */
    373 struct ip6protosw mip6_tunnel_protosw =
    374 {
    375 	.pr_type = SOCK_RAW,
    376 	.pr_domain = &inet6domain,
    377 	.pr_protocol = IPPROTO_IPV6,
    378 	.pr_flags = PR_ATOMIC|PR_ADDR,
    379 	.pr_input = mip6_tunnel_input,
    380 	.pr_output = rip6_output,
    381 	.pr_ctloutput = rip6_ctloutput,
    382 	.pr_usrreq = rip6_usrreq,
    383 };
    384 #endif /* MOBILE_IPV6 */
    385 
    386 static const struct sockaddr_in6 in6_any = {
    387 	  .sin6_len = sizeof(in6_any)
    388 	, .sin6_family = AF_INET6
    389 	, .sin6_port = 0
    390 	, .sin6_flowinfo = 0
    391 	, .sin6_addr = IN6ADDR_ANY_INIT
    392 	, .sin6_scope_id = 0
    393 };
    394 
    395 struct domain inet6domain = {
    396 	.dom_family = AF_INET6, .dom_name = "internet6",
    397 	.dom_init = NULL, .dom_externalize = NULL, .dom_dispose = NULL,
    398 	.dom_protosw = (const struct protosw *)inet6sw,
    399 	.dom_protoswNPROTOSW = (const struct protosw *)&inet6sw[sizeof(inet6sw)/sizeof(inet6sw[0])],
    400 	.dom_rtattach = rn_inithead,
    401 	.dom_rtoffset = offsetof(struct sockaddr_in6, sin6_addr) << 3,
    402 	.dom_maxrtkey = sizeof(struct sockaddr_in6),
    403 	.dom_ifattach = in6_domifattach, .dom_ifdetach = in6_domifdetach,
    404 	.dom_ifqueues = { &ip6intrq, NULL },
    405 	.dom_link = { NULL },
    406 	.dom_mowner = MOWNER_INIT("",""),
    407 	.dom_sa_cmpofs = offsetof(struct sockaddr_in6, sin6_addr),
    408 	.dom_sa_cmplen = sizeof(struct in6_addr),
    409 	.dom_sa_any = (const struct sockaddr *)&in6_any,
    410 	.dom_rtcache = LIST_HEAD_INITIALIZER(inet6domain.dom_rtcache)
    411 };
    412 
    413 int
    414 sockaddr_in6_cmp(const struct sockaddr *lsa, const struct sockaddr *rsa)
    415 {
    416 	uint_fast8_t len;
    417 	const uint_fast8_t addrofs = offsetof(struct sockaddr_in6, sin6_addr),
    418 			   addrend = addrofs + sizeof(struct in6_addr);
    419 	int rc;
    420 	const struct sockaddr_in6 *lsin6, *rsin6;
    421 
    422 	lsin6 = satocsin6(lsa);
    423 	rsin6 = satocsin6(rsa);
    424 
    425 	len = MIN(addrend, MIN(lsin6->sin6_len, rsin6->sin6_len));
    426 
    427 	if (len > addrofs &&
    428 	    (rc = memcmp(&lsin6->sin6_addr, &rsin6->sin6_addr,
    429 	                  len - addrofs)) != 0)
    430 		return rc;
    431 
    432 	return lsin6->sin6_len - rsin6->sin6_len;
    433 }
    434 
    435 /*
    436  * Internet configuration info
    437  */
    438 #ifndef	IPV6FORWARDING
    439 #ifdef GATEWAY6
    440 #define	IPV6FORWARDING	1	/* forward IP6 packets not for us */
    441 #else
    442 #define	IPV6FORWARDING	0	/* don't forward IP6 packets not for us */
    443 #endif /* GATEWAY6 */
    444 #endif /* !IPV6FORWARDING */
    445 
    446 int	ip6_forwarding = IPV6FORWARDING;	/* act as router? */
    447 int	ip6_sendredirects = 1;
    448 int	ip6_defhlim = IPV6_DEFHLIM;
    449 int	ip6_defmcasthlim = IPV6_DEFAULT_MULTICAST_HOPS;
    450 int	ip6_accept_rtadv = 0;	/* "IPV6FORWARDING ? 0 : 1" is dangerous */
    451 int	ip6_maxfragpackets = 200;
    452 int	ip6_maxfrags = 200;
    453 int	ip6_log_interval = 5;
    454 int	ip6_hdrnestlimit = 50;	/* appropriate? */
    455 int	ip6_dad_count = 1;	/* DupAddrDetectionTransmits */
    456 int	ip6_auto_flowlabel = 1;
    457 int	ip6_use_deprecated = 1;	/* allow deprecated addr (RFC2462 5.5.4) */
    458 int	ip6_rr_prune = 5;	/* router renumbering prefix
    459 				 * walk list every 5 sec. */
    460 int	ip6_mcast_pmtu = 0;	/* enable pMTU discovery for multicast? */
    461 int	ip6_v6only = 1;
    462 
    463 int	ip6_keepfaith = 0;
    464 time_t	ip6_log_time = (time_t)0L;
    465 
    466 /* icmp6 */
    467 /*
    468  * BSDI4 defines these variables in in_proto.c...
    469  * XXX: what if we don't define INET? Should we define pmtu6_expire
    470  * or so? (jinmei (at) kame.net 19990310)
    471  */
    472 int pmtu_expire = 60*10;
    473 
    474 /* raw IP6 parameters */
    475 /*
    476  * Nominal space allocated to a raw ip socket.
    477  */
    478 #define	RIPV6SNDQ	8192
    479 #define	RIPV6RCVQ	8192
    480 
    481 u_long	rip6_sendspace = RIPV6SNDQ;
    482 u_long	rip6_recvspace = RIPV6RCVQ;
    483 
    484 /* ICMPV6 parameters */
    485 int	icmp6_rediraccept = 1;		/* accept and process redirects */
    486 int	icmp6_redirtimeout = 10 * 60;	/* 10 minutes */
    487 int	icmp6errppslim = 100;		/* 100pps */
    488 int	icmp6_nodeinfo = 1;		/* enable/disable NI response */
    489 
    490 /* UDP on IP6 parameters */
    491 int	udp6_sendspace = 9216;		/* really max datagram size */
    492 int	udp6_recvspace = 40 * (1024 + sizeof(struct sockaddr_in6));
    493 					/* 40 1K datagrams */
    494