2 /* $KAME: in6_proto.c,v 1.64 2000/06/20 16:20:27 itojun Exp $ */
5 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
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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.
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
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25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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34 * Copyright (c) 1982, 1986, 1993
35 * The Regents of the University of California. All rights reserved.
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38 * modification, are permitted provided that the following conditions
40 * 1. Redistributions of source code must retain the above copyright
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47 * This product includes software developed by the University of
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50 * may be used to endorse or promote products derived from this software
51 * without specific prior written permission.
53 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
54 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
55 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
56 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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58 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
59 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
60 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
61 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
62 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
65 * @(#)in_proto.c 8.1 (Berkeley) 6/10/93
69 #include "opt_inet6.h"
70 #include "opt_ipsec.h"
72 #include <sys/param.h>
73 #include <sys/socket.h>
74 #include <sys/socketvar.h>
75 #include <sys/protosw.h>
76 #include <sys/kernel.h>
77 #include <sys/domain.h>
79 #include <sys/systm.h>
80 #include <sys/sysctl.h>
83 #include <net/radix.h>
84 #include <net/route.h>
86 #include <netinet/in.h>
87 #include <netinet/in_systm.h>
88 #include <netinet/in_var.h>
89 #include <netinet/ip_encap.h>
90 #include <netinet/ip.h>
91 #include <netinet/ip_var.h>
92 #include <netinet/ip6.h>
93 #include <netinet6/ip6_var.h>
94 #include <netinet/icmp6.h>
96 #include <netinet/tcp.h>
97 #include <netinet/tcp_timer.h>
98 #include <netinet/tcp_var.h>
99 #include <netinet/udp.h>
100 #include <netinet/udp_var.h>
101 #include <netinet6/tcp6_var.h>
103 #include <netinet6/udp6_var.h>
105 #include <netinet6/pim6_var.h>
107 #include <netinet6/nd6.h>
108 #include <netinet6/in6_prefix.h>
111 #include <netinet6/ipsec.h>
112 #include <netinet6/ipsec6.h>
113 #include <netinet6/ah.h>
114 #include <netinet6/ah6.h>
116 #include <netinet6/esp.h>
117 #include <netinet6/esp6.h>
119 #include <netinet6/ipcomp.h>
120 #include <netinet6/ipcomp6.h>
123 #include <netinet6/ip6protosw.h>
127 #include <netinet6/in6_gif.h>
130 #include <net/net_osdep.h>
132 #define offsetof(type, member) ((size_t)(&((type *)0)->member))
135 * TCP/IP protocol family: IP6, ICMP6, UDP, TCP.
138 extern struct domain inet6domain;
139 static struct pr_usrreqs nousrreqs;
141 struct ip6protosw inet6sw[] = {
142 { 0, &inet6domain, IPPROTO_IPV6, 0,
145 ip6_init, 0, frag6_slowtimo, frag6_drain,
148 { SOCK_DGRAM, &inet6domain, IPPROTO_UDP, PR_ATOMIC | PR_ADDR,
149 udp6_input, 0, udp6_ctlinput, ip6_ctloutput,
154 { SOCK_STREAM, &inet6domain, IPPROTO_TCP, PR_CONNREQUIRED | PR_WANTRCVD,
155 tcp6_input, 0, tcp6_ctlinput, tcp_ctloutput,
157 #ifdef INET /* don't call timeout routines twice */
158 tcp_init, 0, 0, tcp_drain,
160 tcp_init, tcp_fasttimo, tcp_slowtimo, tcp_drain,
164 { SOCK_RAW, &inet6domain, IPPROTO_RAW, PR_ATOMIC | PR_ADDR,
165 rip6_input, rip6_output, rip6_ctlinput, rip6_ctloutput,
170 { SOCK_RAW, &inet6domain, IPPROTO_ICMPV6, PR_ATOMIC | PR_ADDR,
171 icmp6_input, rip6_output, 0, rip6_ctloutput,
173 icmp6_init, icmp6_fasttimo, 0, 0,
176 { SOCK_RAW, &inet6domain, IPPROTO_DSTOPTS,PR_ATOMIC|PR_ADDR,
177 dest6_input, 0, 0, 0,
182 { SOCK_RAW, &inet6domain, IPPROTO_ROUTING,PR_ATOMIC|PR_ADDR,
183 route6_input, 0, 0, 0,
188 { SOCK_RAW, &inet6domain, IPPROTO_FRAGMENT,PR_ATOMIC|PR_ADDR,
189 frag6_input, 0, 0, 0,
195 { SOCK_RAW, &inet6domain, IPPROTO_AH, PR_ATOMIC|PR_ADDR,
202 { SOCK_RAW, &inet6domain, IPPROTO_ESP, PR_ATOMIC|PR_ADDR,
209 { SOCK_RAW, &inet6domain, IPPROTO_IPCOMP, PR_ATOMIC|PR_ADDR,
210 ipcomp6_input, 0, 0, 0,
217 { SOCK_RAW, &inet6domain, IPPROTO_IPV4, PR_ATOMIC|PR_ADDR,
218 encap6_input, rip6_output, 0, rip6_ctloutput,
224 { SOCK_RAW, &inet6domain, IPPROTO_IPV6, PR_ATOMIC|PR_ADDR,
225 encap6_input, rip6_output, 0, rip6_ctloutput,
234 { SOCK_RAW, &inet6domain, IPPROTO_PIM, PR_ATOMIC|PR_ADDR,
235 pim6_input, rip6_output, 0, rip6_ctloutput,
241 { SOCK_RAW, &inet6domain, 0, PR_ATOMIC | PR_ADDR,
242 rip6_input, rip6_output, 0, rip6_ctloutput,
250 struct ip6protosw in6_gif_protosw =
251 { SOCK_RAW, &inet6domain, 0/*IPPROTO_IPV[46]*/, PR_ATOMIC|PR_ADDR,
252 in6_gif_input, rip6_output, 0, rip6_ctloutput,
259 extern int in6_inithead __P((void **, int));
261 struct domain inet6domain =
262 { AF_INET6, "internet6", 0, 0, 0,
263 (struct protosw *)inet6sw,
264 (struct protosw *)&inet6sw[sizeof(inet6sw)/sizeof(inet6sw[0])], 0,
266 offsetof(struct sockaddr_in6, sin6_addr) << 3,
267 sizeof(struct sockaddr_in6) };
272 * Internet configuration info
274 #ifndef IPV6FORWARDING
276 #define IPV6FORWARDING 1 /* forward IP6 packets not for us */
278 #define IPV6FORWARDING 0 /* don't forward IP6 packets not for us */
279 #endif /* GATEWAY6 */
280 #endif /* !IPV6FORWARDING */
282 #ifndef IPV6_SENDREDIRECTS
283 #define IPV6_SENDREDIRECTS 1
286 int ip6_forwarding = IPV6FORWARDING; /* act as router? */
287 int ip6_sendredirects = IPV6_SENDREDIRECTS;
288 int ip6_defhlim = IPV6_DEFHLIM;
289 int ip6_defmcasthlim = IPV6_DEFAULT_MULTICAST_HOPS;
290 int ip6_accept_rtadv = 0; /* "IPV6FORWARDING ? 0 : 1" is dangerous */
291 int ip6_maxfragpackets = 200;
292 int ip6_log_interval = 5;
293 int ip6_hdrnestlimit = 50; /* appropriate? */
294 int ip6_dad_count = 1; /* DupAddrDetectionTransmits */
295 u_int32_t ip6_flow_seq;
296 int ip6_auto_flowlabel = 1;
298 int ip6_gif_hlim = GIF_HLIM;
300 int ip6_gif_hlim = 0;
302 int ip6_use_deprecated = 1; /* allow deprecated addr (RFC2462 5.5.4) */
303 int ip6_rr_prune = 5; /* router renumbering prefix
304 * walk list every 5 sec. */
305 int ip6_mapped_addr_on = 1;
307 u_int32_t ip6_id = 0UL;
308 int ip6_keepfaith = 0;
309 time_t ip6_log_time = (time_t)0L;
313 * BSDI4 defines these variables in in_proto.c...
314 * XXX: what if we don't define INET? Should we define pmtu6_expire
315 * or so? (jinmei@kame.net 19990310)
317 int pmtu_expire = 60*10;
318 int pmtu_probe = 60*2;
320 /* raw IP6 parameters */
322 * Nominal space allocated to a raw ip socket.
324 #define RIPV6SNDQ 8192
325 #define RIPV6RCVQ 8192
327 u_long rip6_sendspace = RIPV6SNDQ;
328 u_long rip6_recvspace = RIPV6RCVQ;
330 /* ICMPV6 parameters */
331 int icmp6_rediraccept = 1; /* accept and process redirects */
332 int icmp6_redirtimeout = 10 * 60; /* 10 minutes */
333 struct timeval icmp6errratelim = { 0, 0 }; /* no ratelimit */
334 int icmp6errppslim = 100; /* 100pps */
335 int icmp6_nodeinfo = 1; /* enable/disable NI response */
338 /* TCP on IP6 parameters */
339 int tcp6_sendspace = 1024 * 8;
340 int tcp6_recvspace = 1024 * 8;
341 int tcp6_mssdflt = TCP6_MSS;
342 int tcp6_rttdflt = TCP6TV_SRTTDFLT / PR_SLOWHZ;
343 int tcp6_do_rfc1323 = 1;
344 int tcp6_conntimeo = TCP6TV_KEEP_INIT; /* initial connection timeout */
345 int tcp6_43maxseg = 0;
349 * Parameters for keepalive option.
350 * Connections for which SO_KEEPALIVE is set will be probed
351 * after being idle for a time of tcp6_keepidle (in units of PR_SLOWHZ).
352 * Starting at that time, the connection is probed at intervals
353 * of tcp6_keepintvl (same units) until a response is received
354 * or until tcp6_keepcnt probes have been made, at which time
355 * the connection is dropped. Note that a tcp6_keepidle value
356 * under 2 hours is nonconformant with RFC-1122, Internet Host Requirements.
358 int tcp6_keepidle = TCP6TV_KEEP_IDLE; /* time before probing idle */
359 int tcp6_keepintvl = TCP6TV_KEEPINTVL; /* interval betwn idle probes */
360 int tcp6_keepcnt = TCP6TV_KEEPCNT; /* max idle probes */
361 int tcp6_maxpersistidle = TCP6TV_KEEP_IDLE; /* max idle time in persist */
364 #define TCP6_LISTEN_HASH_SIZE 17
365 #define TCP6_CONN_HASH_SIZE 97
366 #define TCP6_SYN_HASH_SIZE 293
367 #define TCP6_SYN_BUCKET_SIZE 35
369 #define TCP6_LISTEN_HASH_SIZE 97
370 #define TCP6_CONN_HASH_SIZE 9973
371 #define TCP6_SYN_HASH_SIZE 997
372 #define TCP6_SYN_BUCKET_SIZE 35
374 int tcp6_listen_hash_size = TCP6_LISTEN_HASH_SIZE;
375 int tcp6_conn_hash_size = TCP6_CONN_HASH_SIZE;
376 struct tcp6_hash_list tcp6_listen_hash[TCP6_LISTEN_HASH_SIZE],
377 tcp6_conn_hash[TCP6_CONN_HASH_SIZE];
379 int tcp6_syn_cache_size = TCP6_SYN_HASH_SIZE;
380 int tcp6_syn_cache_limit = TCP6_SYN_HASH_SIZE*TCP6_SYN_BUCKET_SIZE;
381 int tcp6_syn_bucket_limit = 3*TCP6_SYN_BUCKET_SIZE;
382 struct syn_cache_head6 tcp6_syn_cache[TCP6_SYN_HASH_SIZE];
383 struct syn_cache_head6 *tcp6_syn_cache_first;
384 int tcp6_syn_cache_interval = 8; /* runs timer every 4 seconds */
385 int tcp6_syn_cache_timeo = TCP6TV_KEEP_INIT;
388 * Parameters for computing a desirable data segment size
389 * given an upper bound (either interface MTU, or peer's MSS option)_.
390 * As applications tend to use a buffer size that is a multiple
391 * of kilobytes, try for something that divides evenly. However,
392 * do not round down too much.
394 * Round segment size down to a multiple of TCP6_ROUNDSIZE if this
395 * does not result in lowering by more than (size/TCP6_ROUNDFRAC).
396 * For example, round 536 to 512. Older versions of the system
397 * effectively used MCLBYTES (1K or 2K) as TCP6_ROUNDSIZE, with
398 * a value of 1 for TCP6_ROUNDFRAC (eliminating its effect).
399 * We round to a multiple of 256 for SLIP.
401 #ifndef TCP6_ROUNDSIZE
402 #define TCP6_ROUNDSIZE 256 /* round to multiple of 256 */
404 #ifndef TCP6_ROUNDFRAC
405 #define TCP6_ROUNDFRAC 10 /* round down at most N/10, or 10% */
408 int tcp6_roundsize = TCP6_ROUNDSIZE;
409 int tcp6_roundfrac = TCP6_ROUNDFRAC;
412 /* UDP on IP6 parameters */
413 int udp6_sendspace = 9216; /* really max datagram size */
414 int udp6_recvspace = 40 * (1024 + sizeof(struct sockaddr_in6));
415 /* 40 1K datagrams */
418 * sysctl related items.
420 SYSCTL_NODE(_net, PF_INET6, inet6, CTLFLAG_RW, 0,
424 SYSCTL_NODE(_net_inet6, IPPROTO_IPV6, ip6, CTLFLAG_RW, 0, "IP6");
425 SYSCTL_NODE(_net_inet6, IPPROTO_ICMPV6, icmp6, CTLFLAG_RW, 0, "ICMP6");
426 SYSCTL_NODE(_net_inet6, IPPROTO_UDP, udp6, CTLFLAG_RW, 0, "UDP6");
427 SYSCTL_NODE(_net_inet6, IPPROTO_TCP, tcp6, CTLFLAG_RW, 0, "TCP6");
429 SYSCTL_NODE(_net_inet6, IPPROTO_ESP, ipsec6, CTLFLAG_RW, 0, "IPSEC6");
434 sysctl_ip6_forwarding(SYSCTL_HANDLER_ARGS)
437 int old_ip6_forwarding;
440 error = SYSCTL_OUT(req, arg1, sizeof(int));
441 if (error || !req->newptr)
443 old_ip6_forwarding = ip6_forwarding;
444 error = SYSCTL_IN(req, arg1, sizeof(int));
447 changed = (ip6_forwarding ? 1 : 0) ^ (old_ip6_forwarding ? 1 : 0);
451 * XXX while host->router removes prefix got from RA,
452 * router->host case nukes all the prefixes managed by in6_prefix.c
453 * (both RR and static). therefore, switching from host->router->host
454 * will remove statically configured addresses/prefixes.
455 * not sure if it is intended behavior or not.
457 if (ip6_forwarding != 0) { /* host becomes router */
459 struct nd_prefix *pr, *next;
461 for (pr = nd_prefix.lh_first; pr; pr = next) {
462 next = pr->ndpr_next;
463 if (!IN6_IS_ADDR_UNSPECIFIED(&pr->ndpr_addr))
464 in6_ifdel(pr->ndpr_ifp, &pr->ndpr_addr);
468 } else { /* router becomes host */
469 while(!LIST_EMPTY(&rr_prefix))
470 delete_each_prefix(LIST_FIRST(&rr_prefix),
478 sysctl_icmp6_ratelimit (SYSCTL_HANDLER_ARGS)
480 int rate_usec, error, s;
483 * The sysctl specifies the rate in usec-between-icmp,
484 * so we must convert from/to a timeval.
486 rate_usec = (icmp6errratelim.tv_sec * 1000000) +
487 icmp6errratelim.tv_usec;
488 error = sysctl_handle_int(oidp, &rate_usec, 0, req);
494 icmp6errratelim.tv_sec = rate_usec / 1000000;
495 icmp6errratelim.tv_usec = rate_usec % 1000000;
501 SYSCTL_OID(_net_inet6_ip6, IPV6CTL_FORWARDING, forwarding,
502 CTLTYPE_INT|CTLFLAG_RW, &ip6_forwarding, 0, sysctl_ip6_forwarding,
504 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_SENDREDIRECTS,
505 redirect, CTLFLAG_RW, &ip6_sendredirects, 0, "");
506 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_DEFHLIM,
507 hlim, CTLFLAG_RW, &ip6_defhlim, 0, "");
508 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_MAXFRAGPACKETS,
509 maxfragpackets, CTLFLAG_RW, &ip6_maxfragpackets, 0, "");
510 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_ACCEPT_RTADV,
511 accept_rtadv, CTLFLAG_RW, &ip6_accept_rtadv, 0, "");
512 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_KEEPFAITH,
513 keepfaith, CTLFLAG_RW, &ip6_keepfaith, 0, "");
514 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_LOG_INTERVAL,
515 log_interval, CTLFLAG_RW, &ip6_log_interval, 0, "");
516 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_HDRNESTLIMIT,
517 hdrnestlimit, CTLFLAG_RW, &ip6_hdrnestlimit, 0, "");
518 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_DAD_COUNT,
519 dad_count, CTLFLAG_RW, &ip6_dad_count, 0, "");
520 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_AUTO_FLOWLABEL,
521 auto_flowlabel, CTLFLAG_RW, &ip6_auto_flowlabel, 0, "");
522 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_DEFMCASTHLIM,
523 defmcasthlim, CTLFLAG_RW, &ip6_defmcasthlim, 0, "");
524 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_GIF_HLIM,
525 gifhlim, CTLFLAG_RW, &ip6_gif_hlim, 0, "");
526 SYSCTL_STRING(_net_inet6_ip6, IPV6CTL_KAME_VERSION,
527 kame_version, CTLFLAG_RD, __KAME_VERSION, 0, "");
528 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_USE_DEPRECATED,
529 use_deprecated, CTLFLAG_RW, &ip6_use_deprecated, 0, "");
530 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_RR_PRUNE,
531 rr_prune, CTLFLAG_RW, &ip6_rr_prune, 0, "");
532 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_MAPPED_ADDR,
533 mapped_addr, CTLFLAG_RW, &ip6_mapped_addr_on, 0, "");
535 /* net.inet6.icmp6 */
536 SYSCTL_INT(_net_inet6_icmp6, ICMPV6CTL_REDIRACCEPT,
537 rediraccept, CTLFLAG_RW, &icmp6_rediraccept, 0, "");
538 SYSCTL_INT(_net_inet6_icmp6, ICMPV6CTL_REDIRTIMEOUT,
539 redirtimeout, CTLFLAG_RW, &icmp6_redirtimeout, 0, "");
540 SYSCTL_STRUCT(_net_inet6_icmp6, ICMPV6CTL_STATS, stats, CTLFLAG_RD,
541 &icmp6stat, icmp6stat, "");
542 SYSCTL_PROC(_net_inet6_icmp6, ICMPV6CTL_ERRRATELIMIT,
543 errratelimit, CTLTYPE_INT|CTLFLAG_RW,
544 0, sizeof(int), sysctl_icmp6_ratelimit, "I", "");
545 SYSCTL_INT(_net_inet6_icmp6, ICMPV6CTL_ND6_PRUNE,
546 nd6_prune, CTLFLAG_RW, &nd6_prune, 0, "");
547 SYSCTL_INT(_net_inet6_icmp6, ICMPV6CTL_ND6_DELAY,
548 nd6_delay, CTLFLAG_RW, &nd6_delay, 0, "");
549 SYSCTL_INT(_net_inet6_icmp6, ICMPV6CTL_ND6_UMAXTRIES,
550 nd6_umaxtries, CTLFLAG_RW, &nd6_umaxtries, 0, "");
551 SYSCTL_INT(_net_inet6_icmp6, ICMPV6CTL_ND6_MMAXTRIES,
552 nd6_mmaxtries, CTLFLAG_RW, &nd6_mmaxtries, 0, "");
553 SYSCTL_INT(_net_inet6_icmp6, ICMPV6CTL_ND6_USELOOPBACK,
554 nd6_useloopback, CTLFLAG_RW, &nd6_useloopback, 0, "");
555 SYSCTL_INT(_net_inet6_icmp6, ICMPV6CTL_NODEINFO,
556 nodeinfo, CTLFLAG_RW, &icmp6_nodeinfo, 0, "");
557 SYSCTL_INT(_net_inet6_icmp6, ICMPV6CTL_ERRPPSLIMIT,
558 errppslimit, CTLFLAG_RW, &icmp6errppslim, 0, "");
559 SYSCTL_INT(_net_inet6_icmp6, ICMPV6CTL_ND6_MAXNUDHINT,
560 nd6_maxnudhint, CTLFLAG_RW, &nd6_maxnudhint, 0, "");