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in6_proto.c revision 1.70
      1  1.70  degroote /*	$NetBSD: in6_proto.c,v 1.70 2007/02/10 09:43:05 degroote Exp $	*/
      2  1.21    itojun /*	$KAME: in6_proto.c,v 1.66 2000/10/10 15:35:47 itojun Exp $	*/
      3   1.3   thorpej 
      4   1.2    itojun /*
      5   1.2    itojun  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
      6   1.2    itojun  * All rights reserved.
      7  1.18    itojun  *
      8   1.2    itojun  * Redistribution and use in source and binary forms, with or without
      9   1.2    itojun  * modification, are permitted provided that the following conditions
     10   1.2    itojun  * are met:
     11   1.2    itojun  * 1. Redistributions of source code must retain the above copyright
     12   1.2    itojun  *    notice, this list of conditions and the following disclaimer.
     13   1.2    itojun  * 2. Redistributions in binary form must reproduce the above copyright
     14   1.2    itojun  *    notice, this list of conditions and the following disclaimer in the
     15   1.2    itojun  *    documentation and/or other materials provided with the distribution.
     16   1.2    itojun  * 3. Neither the name of the project nor the names of its contributors
     17   1.2    itojun  *    may be used to endorse or promote products derived from this software
     18   1.2    itojun  *    without specific prior written permission.
     19  1.18    itojun  *
     20   1.2    itojun  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
     21   1.2    itojun  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     22   1.2    itojun  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     23   1.2    itojun  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
     24   1.2    itojun  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     25   1.2    itojun  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     26   1.2    itojun  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     27   1.2    itojun  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     28   1.2    itojun  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     29   1.2    itojun  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     30   1.2    itojun  * SUCH DAMAGE.
     31   1.2    itojun  */
     32   1.2    itojun 
     33   1.2    itojun /*
     34   1.2    itojun  * Copyright (c) 1982, 1986, 1993
     35   1.2    itojun  *	The Regents of the University of California.  All rights reserved.
     36   1.2    itojun  *
     37   1.2    itojun  * Redistribution and use in source and binary forms, with or without
     38   1.2    itojun  * modification, are permitted provided that the following conditions
     39   1.2    itojun  * are met:
     40   1.2    itojun  * 1. Redistributions of source code must retain the above copyright
     41   1.2    itojun  *    notice, this list of conditions and the following disclaimer.
     42   1.2    itojun  * 2. Redistributions in binary form must reproduce the above copyright
     43   1.2    itojun  *    notice, this list of conditions and the following disclaimer in the
     44   1.2    itojun  *    documentation and/or other materials provided with the distribution.
     45  1.49       agc  * 3. Neither the name of the University nor the names of its contributors
     46   1.2    itojun  *    may be used to endorse or promote products derived from this software
     47   1.2    itojun  *    without specific prior written permission.
     48   1.2    itojun  *
     49   1.2    itojun  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     50   1.2    itojun  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     51   1.2    itojun  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     52   1.2    itojun  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     53   1.2    itojun  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     54   1.2    itojun  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     55   1.2    itojun  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     56   1.2    itojun  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     57   1.2    itojun  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     58   1.2    itojun  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     59   1.2    itojun  * SUCH DAMAGE.
     60   1.2    itojun  *
     61   1.2    itojun  *	@(#)in_proto.c	8.1 (Berkeley) 6/10/93
     62   1.2    itojun  */
     63  1.34     lukem 
     64  1.34     lukem #include <sys/cdefs.h>
     65  1.70  degroote __KERNEL_RCSID(0, "$NetBSD: in6_proto.c,v 1.70 2007/02/10 09:43:05 degroote Exp $");
     66   1.2    itojun 
     67   1.2    itojun #include "opt_inet.h"
     68   1.4   thorpej #include "opt_ipsec.h"
     69  1.26    itojun #include "opt_iso.h"
     70   1.2    itojun 
     71   1.2    itojun #include <sys/param.h>
     72   1.2    itojun #include <sys/socket.h>
     73   1.2    itojun #include <sys/protosw.h>
     74   1.2    itojun #include <sys/kernel.h>
     75   1.2    itojun #include <sys/domain.h>
     76   1.2    itojun #include <sys/mbuf.h>
     77   1.2    itojun 
     78   1.2    itojun #include <net/if.h>
     79   1.2    itojun #include <net/radix.h>
     80   1.2    itojun #include <net/route.h>
     81   1.2    itojun 
     82   1.2    itojun #include <netinet/in.h>
     83   1.2    itojun #include <netinet/in_systm.h>
     84   1.2    itojun #include <netinet/in_var.h>
     85  1.17    itojun #include <netinet/ip_encap.h>
     86   1.2    itojun #include <netinet/ip.h>
     87   1.2    itojun #include <netinet/ip_var.h>
     88   1.2    itojun #include <netinet/in_pcb.h>
     89  1.13    itojun #include <netinet/ip6.h>
     90   1.2    itojun #include <netinet6/ip6_var.h>
     91  1.13    itojun #include <netinet/icmp6.h>
     92   1.2    itojun #include <netinet6/in6_pcb.h>
     93   1.2    itojun 
     94   1.2    itojun #include <netinet/tcp.h>
     95   1.2    itojun #include <netinet/tcp_fsm.h>
     96   1.2    itojun #include <netinet/tcp_seq.h>
     97   1.2    itojun #include <netinet/tcp_timer.h>
     98   1.2    itojun #include <netinet/tcp_var.h>
     99   1.2    itojun #include <netinet/tcpip.h>
    100   1.2    itojun #include <netinet/tcp_debug.h>
    101   1.2    itojun 
    102   1.2    itojun #include <netinet6/udp6.h>
    103   1.2    itojun #include <netinet6/udp6_var.h>
    104   1.2    itojun 
    105   1.2    itojun #include <netinet6/pim6_var.h>
    106   1.2    itojun 
    107   1.2    itojun #include <netinet6/nd6.h>
    108   1.2    itojun 
    109   1.2    itojun #ifdef IPSEC
    110   1.9    itojun #include <netinet6/ipsec.h>
    111   1.2    itojun #include <netinet6/ah.h>
    112   1.2    itojun #ifdef IPSEC_ESP
    113   1.2    itojun #include <netinet6/esp.h>
    114   1.2    itojun #endif
    115   1.2    itojun #include <netinet6/ipcomp.h>
    116  1.32    itojun #endif /* IPSEC */
    117   1.2    itojun 
    118  1.70  degroote #ifdef FAST_IPSEC
    119  1.70  degroote #include <netipsec/ipsec.h>
    120  1.70  degroote #include <netipsec/ipsec6.h>
    121  1.70  degroote #include <netipsec/key.h>
    122  1.70  degroote #endif /* FAST_IPSEC */
    123  1.70  degroote 
    124  1.70  degroote 
    125  1.63  liamjfoy #include "carp.h"
    126  1.63  liamjfoy #if NCARP > 0
    127  1.63  liamjfoy #include <netinet/ip_carp.h>
    128  1.63  liamjfoy #endif
    129  1.63  liamjfoy 
    130  1.68    rpaulo #include "etherip.h"
    131  1.68    rpaulo #if NETHERIP > 1
    132  1.68    rpaulo #include <netinet6/ip6_etherip.h>
    133  1.68    rpaulo #endif
    134  1.68    rpaulo 
    135   1.2    itojun #include <netinet6/ip6protosw.h>
    136   1.2    itojun 
    137  1.35    itojun #include <net/net_osdep.h>
    138  1.35    itojun 
    139  1.47   thorpej #ifndef offsetof		/* XXX */
    140   1.2    itojun #define	offsetof(type, member)	((size_t)(&((type *)0)->member))
    141  1.47   thorpej #endif
    142   1.2    itojun 
    143   1.2    itojun /*
    144   1.2    itojun  * TCP/IP protocol family: IP6, ICMP6, UDP, TCP.
    145   1.2    itojun  */
    146   1.2    itojun 
    147  1.58      matt DOMAIN_DEFINE(inet6domain);	/* forward declare and add to link set */
    148   1.2    itojun 
    149  1.57      matt const struct ip6protosw inet6sw[] = {
    150   1.2    itojun { 0,		&inet6domain,	IPPROTO_IPV6,	0,
    151   1.2    itojun   0,		0,		0,		0,
    152   1.2    itojun   0,
    153   1.9    itojun   ip6_init,	0,		frag6_slowtimo,	frag6_drain,
    154   1.2    itojun },
    155  1.60       gdt { SOCK_DGRAM,	&inet6domain,	IPPROTO_UDP,	PR_ATOMIC|PR_ADDR|PR_PURGEIF,
    156   1.2    itojun   udp6_input,	0,		udp6_ctlinput,	ip6_ctloutput,
    157  1.12    itojun   udp6_usrreq,	udp6_init,
    158   1.9    itojun   0,		0,		0,
    159   1.2    itojun },
    160  1.60       gdt { SOCK_STREAM,	&inet6domain,	IPPROTO_TCP,	PR_CONNREQUIRED|PR_WANTRCVD|PR_LISTEN|PR_ABRTACPTDIS|PR_PURGEIF,
    161   1.2    itojun   tcp6_input,	0,		tcp6_ctlinput,	tcp_ctloutput,
    162   1.2    itojun   tcp_usrreq,
    163  1.20     enami #ifdef INET	/* don't call initialization and timeout routines twice */
    164  1.51    itojun   0,		0,		0,		0,
    165   1.9    itojun #else
    166  1.52    itojun   tcp_init,	0,		tcp_slowtimo,	tcp_drain,
    167   1.9    itojun #endif
    168   1.2    itojun },
    169  1.60       gdt { SOCK_RAW,	&inet6domain,	IPPROTO_RAW,	PR_ATOMIC|PR_ADDR|PR_PURGEIF,
    170  1.16    itojun   rip6_input,	rip6_output,	rip6_ctlinput,	rip6_ctloutput,
    171   1.2    itojun   rip6_usrreq,
    172   1.9    itojun   0,		0,		0,		0,
    173   1.2    itojun },
    174  1.28    itojun { SOCK_RAW,	&inet6domain,	IPPROTO_ICMPV6,	PR_ATOMIC|PR_ADDR|PR_LASTHDR,
    175  1.25    itojun   icmp6_input,	rip6_output,	rip6_ctlinput,	rip6_ctloutput,
    176   1.2    itojun   rip6_usrreq,
    177  1.62    rpaulo   icmp6_init,	0,		0,		0,
    178   1.2    itojun },
    179   1.2    itojun { SOCK_RAW,	&inet6domain,	IPPROTO_DSTOPTS,PR_ATOMIC|PR_ADDR,
    180   1.2    itojun   dest6_input,	0,	 	0,		0,
    181  1.43    itojun   0,
    182   1.2    itojun   0,		0,		0,		0,
    183   1.2    itojun },
    184   1.2    itojun { SOCK_RAW,	&inet6domain,	IPPROTO_ROUTING,PR_ATOMIC|PR_ADDR,
    185   1.2    itojun   route6_input,	0,	 	0,		0,
    186  1.43    itojun   0,
    187   1.2    itojun   0,		0,		0,		0,
    188   1.2    itojun },
    189   1.2    itojun { SOCK_RAW,	&inet6domain,	IPPROTO_FRAGMENT,PR_ATOMIC|PR_ADDR,
    190   1.2    itojun   frag6_input,	0,	 	0,		0,
    191  1.43    itojun   0,
    192   1.2    itojun   0,		0,		0,		0,
    193   1.2    itojun },
    194   1.2    itojun #ifdef IPSEC
    195   1.2    itojun { SOCK_RAW,	&inet6domain,	IPPROTO_AH,	PR_ATOMIC|PR_ADDR,
    196  1.22    itojun   ah6_input,	0,	 	ah6_ctlinput,	0,
    197  1.43    itojun   0,
    198   1.9    itojun   0,		0,		0,		0,
    199   1.2    itojun },
    200   1.2    itojun #ifdef IPSEC_ESP
    201   1.2    itojun { SOCK_RAW,	&inet6domain,	IPPROTO_ESP,	PR_ATOMIC|PR_ADDR,
    202  1.22    itojun   esp6_input,	0,	 	esp6_ctlinput,	0,
    203  1.43    itojun   0,
    204   1.9    itojun   0,		0,		0,		0,
    205   1.2    itojun },
    206   1.2    itojun #endif
    207   1.2    itojun { SOCK_RAW,	&inet6domain,	IPPROTO_IPCOMP,	PR_ATOMIC|PR_ADDR,
    208   1.2    itojun   ipcomp6_input, 0,	 	0,		0,
    209  1.43    itojun   0,
    210   1.9    itojun   0,		0,		0,		0,
    211   1.2    itojun },
    212   1.2    itojun #endif /* IPSEC */
    213  1.70  degroote #ifdef FAST_IPSEC
    214  1.70  degroote { SOCK_RAW,    &inet6domain,   IPPROTO_AH,     PR_ATOMIC|PR_ADDR,
    215  1.70  degroote   ipsec6_common_input, 0,              ah6_ctlinput,   0,
    216  1.70  degroote   0,
    217  1.70  degroote   0,           0,              0,              0,
    218  1.70  degroote },
    219  1.70  degroote { SOCK_RAW,    &inet6domain,   IPPROTO_ESP,    PR_ATOMIC|PR_ADDR,
    220  1.70  degroote   ipsec6_common_input,    0,           esp6_ctlinput,  0,
    221  1.70  degroote   0,
    222  1.70  degroote   0,           0,              0,              0,
    223  1.70  degroote },
    224  1.70  degroote { SOCK_RAW,    &inet6domain,   IPPROTO_IPCOMP, PR_ATOMIC|PR_ADDR,
    225  1.70  degroote   ipsec6_common_input,    0,           0,              0,
    226  1.70  degroote   0,
    227  1.70  degroote   0,           0,              0,              0,
    228  1.70  degroote },
    229  1.70  degroote #endif /* FAST_IPSEC */
    230  1.17    itojun #ifdef INET
    231  1.28    itojun { SOCK_RAW,	&inet6domain,	IPPROTO_IPV4,	PR_ATOMIC|PR_ADDR|PR_LASTHDR,
    232  1.38    itojun   encap6_input,	rip6_output, 	encap6_ctlinput, rip6_ctloutput,
    233  1.17    itojun   rip6_usrreq,
    234  1.37    itojun   encap_init,	0,		0,		0,
    235   1.2    itojun },
    236  1.17    itojun #endif
    237  1.28    itojun { SOCK_RAW,	&inet6domain,	IPPROTO_IPV6,	PR_ATOMIC|PR_ADDR|PR_LASTHDR,
    238  1.38    itojun   encap6_input, rip6_output,	encap6_ctlinput, rip6_ctloutput,
    239  1.17    itojun   rip6_usrreq,
    240  1.17    itojun   encap_init,	0,		0,		0,
    241   1.2    itojun },
    242  1.68    rpaulo #if NETHERIP > 1
    243  1.68    rpaulo { SOCK_RAW,	&inet6domain,	IPPROTO_ETHERIP,	PR_ATOMIC|PR_ADDR|PR_LASTHDR,
    244  1.68    rpaulo   ip6_etherip_input,	rip6_output,	rip6_ctlinput,	rip6_ctloutput,
    245  1.68    rpaulo   rip6_usrreq,
    246  1.68    rpaulo   0,		0,		0,		0,
    247  1.68    rpaulo },
    248  1.68    rpaulo #endif
    249  1.63  liamjfoy #if NCARP > 0
    250  1.63  liamjfoy { SOCK_RAW,	&inet6domain,	IPPROTO_CARP,	PR_ATOMIC|PR_ADDR,
    251  1.63  liamjfoy   carp6_proto_input,	rip6_output,	0,		rip6_ctloutput,
    252  1.63  liamjfoy   rip6_usrreq,
    253  1.65  christos   0,		0,		0,		0,
    254  1.63  liamjfoy },
    255  1.63  liamjfoy #endif /* NCARP */
    256  1.26    itojun #ifdef ISO
    257  1.28    itojun { SOCK_RAW,	&inet6domain,	IPPROTO_EON,	PR_ATOMIC|PR_ADDR|PR_LASTHDR,
    258  1.38    itojun   encap6_input,	rip6_output,	encap6_ctlinput, rip6_ctloutput,
    259  1.27    itojun   rip6_usrreq,	/*XXX*/
    260  1.37    itojun   encap_init,	0,		0,		0,
    261  1.26    itojun },
    262  1.26    itojun #endif
    263  1.28    itojun { SOCK_RAW,     &inet6domain,	IPPROTO_PIM,	PR_ATOMIC|PR_ADDR|PR_LASTHDR,
    264  1.42    itojun   pim6_input,	rip6_output,	0,              rip6_ctloutput,
    265   1.2    itojun   rip6_usrreq,
    266   1.2    itojun   0,            0,              0,              0,
    267   1.2    itojun },
    268   1.2    itojun /* raw wildcard */
    269  1.50    itojun { SOCK_RAW,	&inet6domain,	0,		PR_ATOMIC|PR_ADDR|PR_LASTHDR,
    270   1.2    itojun   rip6_input,	rip6_output,	0,		rip6_ctloutput,
    271  1.15    itojun   rip6_usrreq,
    272  1.15    itojun   rip6_init,	0,		0,		0,
    273   1.2    itojun },
    274   1.2    itojun };
    275  1.17    itojun 
    276  1.66  christos struct domain inet6domain = {
    277  1.69    dyoung 	.dom_family = AF_INET6, .dom_name = "internet6",
    278  1.69    dyoung 	.dom_init = NULL, .dom_externalize = NULL, .dom_dispose = NULL,
    279  1.69    dyoung 	.dom_protosw = (const struct protosw *)inet6sw,
    280  1.69    dyoung 	.dom_protoswNPROTOSW = (const struct protosw *)&inet6sw[sizeof(inet6sw)/sizeof(inet6sw[0])],
    281  1.69    dyoung 	.dom_rtattach = rn_inithead,
    282  1.69    dyoung 	.dom_rtoffset = offsetof(struct sockaddr_in6, sin6_addr) << 3,
    283  1.69    dyoung 	.dom_maxrtkey = sizeof(struct sockaddr_in6),
    284  1.69    dyoung 	.dom_ifattach = in6_domifattach, .dom_ifdetach = in6_domifdetach,
    285  1.69    dyoung 	.dom_ifqueues = { &ip6intrq, NULL },
    286  1.69    dyoung 	.dom_link = { NULL },
    287  1.69    dyoung 	.dom_mowner = MOWNER_INIT("","")
    288  1.66  christos };
    289   1.2    itojun 
    290   1.2    itojun /*
    291   1.2    itojun  * Internet configuration info
    292   1.2    itojun  */
    293   1.2    itojun #ifndef	IPV6FORWARDING
    294   1.2    itojun #ifdef GATEWAY6
    295   1.2    itojun #define	IPV6FORWARDING	1	/* forward IP6 packets not for us */
    296   1.2    itojun #else
    297   1.2    itojun #define	IPV6FORWARDING	0	/* don't forward IP6 packets not for us */
    298   1.2    itojun #endif /* GATEWAY6 */
    299   1.2    itojun #endif /* !IPV6FORWARDING */
    300   1.2    itojun 
    301   1.2    itojun int	ip6_forwarding = IPV6FORWARDING;	/* act as router? */
    302  1.48    itojun int	ip6_sendredirects = 1;
    303   1.2    itojun int	ip6_defhlim = IPV6_DEFHLIM;
    304   1.2    itojun int	ip6_defmcasthlim = IPV6_DEFAULT_MULTICAST_HOPS;
    305   1.2    itojun int	ip6_accept_rtadv = 0;	/* "IPV6FORWARDING ? 0 : 1" is dangerous */
    306   1.2    itojun int	ip6_maxfragpackets = 200;
    307  1.40    itojun int	ip6_maxfrags = 200;
    308   1.2    itojun int	ip6_log_interval = 5;
    309   1.2    itojun int	ip6_hdrnestlimit = 50;	/* appropriate? */
    310   1.2    itojun int	ip6_dad_count = 1;	/* DupAddrDetectionTransmits */
    311   1.2    itojun int	ip6_auto_flowlabel = 1;
    312  1.45    itojun int	ip6_use_deprecated = 1;	/* allow deprecated addr (RFC2462 5.5.4) */
    313   1.9    itojun int	ip6_rr_prune = 5;	/* router renumbering prefix
    314  1.38    itojun 				 * walk list every 5 sec. */
    315  1.62    rpaulo int	ip6_mcast_pmtu = 0;	/* enable pMTU discovery for multicast? */
    316  1.55    briggs int	ip6_v6only = 1;
    317  1.11    itojun 
    318   1.2    itojun int	ip6_keepfaith = 0;
    319   1.2    itojun time_t	ip6_log_time = (time_t)0L;
    320   1.2    itojun 
    321   1.2    itojun /* icmp6 */
    322   1.9    itojun /*
    323   1.9    itojun  * BSDI4 defines these variables in in_proto.c...
    324   1.9    itojun  * XXX: what if we don't define INET? Should we define pmtu6_expire
    325   1.9    itojun  * or so? (jinmei (at) kame.net 19990310)
    326   1.9    itojun  */
    327   1.2    itojun int pmtu_expire = 60*10;
    328   1.2    itojun 
    329   1.2    itojun /* raw IP6 parameters */
    330   1.2    itojun /*
    331   1.2    itojun  * Nominal space allocated to a raw ip socket.
    332   1.2    itojun  */
    333   1.2    itojun #define	RIPV6SNDQ	8192
    334   1.2    itojun #define	RIPV6RCVQ	8192
    335   1.2    itojun 
    336   1.2    itojun u_long	rip6_sendspace = RIPV6SNDQ;
    337   1.2    itojun u_long	rip6_recvspace = RIPV6RCVQ;
    338   1.2    itojun 
    339   1.2    itojun /* ICMPV6 parameters */
    340   1.2    itojun int	icmp6_rediraccept = 1;		/* accept and process redirects */
    341   1.2    itojun int	icmp6_redirtimeout = 10 * 60;	/* 10 minutes */
    342  1.18    itojun int	icmp6errppslim = 100;		/* 100pps */
    343  1.10    itojun int	icmp6_nodeinfo = 1;		/* enable/disable NI response */
    344   1.2    itojun 
    345   1.2    itojun /* UDP on IP6 parameters */
    346   1.2    itojun int	udp6_sendspace = 9216;		/* really max datagram size */
    347   1.2    itojun int	udp6_recvspace = 40 * (1024 + sizeof(struct sockaddr_in6));
    348   1.2    itojun 					/* 40 1K datagrams */
    349