xref: /freebsd/sys/netinet6/in6_proto.c (revision e1e636193db45630c7881246d25902e57c43d24e)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
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  *	$KAME: in6_proto.c,v 1.91 2001/05/27 13:28:35 itojun Exp $
32  */
33 
34 /*-
35  * Copyright (c) 1982, 1986, 1993
36  *	The Regents of the University of California.  All rights reserved.
37  *
38  * Redistribution and use in source and binary forms, with or without
39  * modification, are permitted provided that the following conditions
40  * are met:
41  * 1. Redistributions of source code must retain the above copyright
42  *    notice, this list of conditions and the following disclaimer.
43  * 2. Redistributions in binary form must reproduce the above copyright
44  *    notice, this list of conditions and the following disclaimer in the
45  *    documentation and/or other materials provided with the distribution.
46  * 3. Neither the name of the University nor the names of its contributors
47  *    may be used to endorse or promote products derived from this software
48  *    without specific prior written permission.
49  *
50  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
51  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
52  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
53  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
54  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
55  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
56  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
57  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
58  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
59  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
60  * SUCH DAMAGE.
61  */
62 
63 #include <sys/cdefs.h>
64 #include "opt_inet.h"
65 #include "opt_inet6.h"
66 #include "opt_ipsec.h"
67 #include "opt_ipstealth.h"
68 #include "opt_sctp.h"
69 #include "opt_route.h"
70 
71 #include <sys/param.h>
72 #include <sys/socket.h>
73 #include <sys/socketvar.h>
74 #include <sys/proc.h>
75 #include <sys/protosw.h>
76 #include <sys/jail.h>
77 #include <sys/kernel.h>
78 #include <sys/malloc.h>
79 #include <sys/domain.h>
80 #include <sys/mbuf.h>
81 #include <sys/systm.h>
82 #include <sys/sysctl.h>
83 
84 #include <net/if.h>
85 #include <net/if_var.h>
86 #include <netinet/in.h>
87 #include <netinet/ip6.h>
88 #include <netinet6/in6_var.h>
89 #include <netinet6/ip6_var.h>
90 #include <netinet/icmp6.h>
91 #include <netinet6/nd6.h>
92 #include <netinet6/raw_ip6.h>
93 
94 /* netinet6/raw_ip6.c */
95 extern struct protosw rip6_protosw;
96 /* netinet6/udp6_usrreq.c */
97 extern struct protosw udp6_protosw, udplite6_protosw;
98 /* netinet/tcp_usrreq.c */
99 extern struct protosw tcp6_protosw;
100 /* netinet/sctp6_usrreq.c */
101 extern struct protosw sctp6_seqpacket_protosw, sctp6_stream_protosw;
102 
103 /*
104  * TCP/IP protocol family: IP6, ICMP6, UDP, TCP.
105  */
106 FEATURE(inet6, "Internet Protocol version 6");
107 
108 struct domain inet6domain = {
109 	.dom_family =		AF_INET6,
110 	.dom_name =		"internet6",
111 	.dom_rtattach =		in6_inithead,
112 #ifdef VIMAGE
113 	.dom_rtdetach =		in6_detachhead,
114 #endif
115 	.dom_ifattach =		in6_domifattach,
116 	.dom_ifdetach =		in6_domifdetach,
117 	.dom_ifmtu    =		in6_domifmtu,
118 	.dom_nprotosw =		14,
119 	.dom_protosw = {
120 		&tcp6_protosw,
121 		&udp6_protosw,
122 #ifdef SCTP
123 		&sctp6_seqpacket_protosw,
124 		&sctp6_stream_protosw,
125 #else
126 		NULL, NULL,
127 #endif
128 		&udplite6_protosw,
129 		&rip6_protosw,
130 		/* Spacer 8 times for loadable protocols. XXXGL: why 8? */
131 		NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
132 	},
133 };
134 
135 DOMAIN_SET(inet6);
136 
137 /*
138  * Internet configuration info
139  */
140 #ifndef	IPV6FORWARDING
141 #ifdef GATEWAY6
142 #define	IPV6FORWARDING	1	/* forward IP6 packets not for us */
143 #else
144 #define	IPV6FORWARDING	0	/* don't forward IP6 packets not for us */
145 #endif /* GATEWAY6 */
146 #endif /* !IPV6FORWARDING */
147 
148 #ifndef	IPV6_SENDREDIRECTS
149 #define	IPV6_SENDREDIRECTS	1
150 #endif
151 
152 VNET_DEFINE(int, ip6_forwarding) = IPV6FORWARDING;	/* act as router? */
153 VNET_DEFINE(int, ip6_sendredirects) = IPV6_SENDREDIRECTS;
154 VNET_DEFINE(int, ip6_defhlim) = IPV6_DEFHLIM;
155 VNET_DEFINE(int, ip6_defmcasthlim) = IPV6_DEFAULT_MULTICAST_HOPS;
156 VNET_DEFINE(int, ip6_accept_rtadv) = 0;
157 VNET_DEFINE(int, ip6_no_radr) = 0;
158 VNET_DEFINE(int, ip6_norbit_raif) = 0;
159 VNET_DEFINE(int, ip6_rfc6204w3) = 0;
160 VNET_DEFINE(int, ip6_hdrnestlimit) = 15;/* How many header options will we
161 					 * process? */
162 VNET_DEFINE(int, ip6_dad_count) = 1;	/* DupAddrDetectionTransmits */
163 VNET_DEFINE(int, ip6_auto_flowlabel) = 1;
164 VNET_DEFINE(int, ip6_use_deprecated) = 1;/* allow deprecated addr
165 					 * (RFC2462 5.5.4) */
166 VNET_DEFINE(int, ip6_rr_prune) = 5;	/* router renumbering prefix
167 					 * walk list every 5 sec. */
168 VNET_DEFINE(int, ip6_mcast_pmtu) = 0;	/* enable pMTU discovery for multicast? */
169 VNET_DEFINE(int, ip6_v6only) = 1;
170 
171 #ifdef IPSTEALTH
172 VNET_DEFINE(int, ip6stealth) = 0;
173 #endif
174 VNET_DEFINE(bool, ip6_log_cannot_forward) = 1;
175 
176 /*
177  * BSDI4 defines these variables in in_proto.c...
178  * XXX: what if we don't define INET? Should we define pmtu6_expire
179  * or so? (jinmei@kame.net 19990310)
180  */
181 VNET_DEFINE(int, pmtu_expire) = 60*10;
182 VNET_DEFINE(int, pmtu_probe) = 60*2;
183 
184 VNET_DEFINE_STATIC(int, ip6_log_interval) = 5;
185 VNET_DEFINE_STATIC(int, ip6_log_count) = 0;
186 VNET_DEFINE_STATIC(struct timeval, ip6_log_last) = { 0 };
187 
188 #define	V_ip6_log_interval	VNET(ip6_log_interval)
189 #define	V_ip6_log_count		VNET(ip6_log_count)
190 #define	V_ip6_log_last		VNET(ip6_log_last)
191 
192 /*
193  * sysctl related items.
194  */
195 SYSCTL_NODE(_net, PF_INET6, inet6, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
196     "Internet6 Family");
197 
198 /* net.inet6 */
199 SYSCTL_NODE(_net_inet6,	IPPROTO_IPV6, ip6, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
200     "IP6");
201 SYSCTL_NODE(_net_inet6,	IPPROTO_ICMPV6, icmp6, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
202     "ICMP6");
203 SYSCTL_NODE(_net_inet6,	IPPROTO_UDP, udp6, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
204     "UDP6");
205 SYSCTL_NODE(_net_inet6,	IPPROTO_TCP, tcp6, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
206     "TCP6");
207 #if defined(SCTP) || defined(SCTP_SUPPORT)
208 SYSCTL_NODE(_net_inet6,	IPPROTO_SCTP, sctp6, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
209     "SCTP6");
210 #endif
211 #if defined(IPSEC) || defined(IPSEC_SUPPORT)
212 SYSCTL_NODE(_net_inet6,	IPPROTO_ESP, ipsec6, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
213     "IPSEC6");
214 #endif /* IPSEC */
215 
216 /* net.inet6.ip6 */
217 static int
218 sysctl_ip6_temppltime(SYSCTL_HANDLER_ARGS)
219 {
220 	int error, val;
221 
222 	val = V_ip6_temp_preferred_lifetime;
223 	error = sysctl_handle_int(oidp, &val, 0, req);
224 	if (error != 0 || !req->newptr)
225 		return (error);
226 	if (val < V_ip6_desync_factor + V_ip6_temp_regen_advance)
227 		return (EINVAL);
228 	V_ip6_temp_preferred_lifetime = val;
229 	return (0);
230 }
231 
232 static int
233 sysctl_ip6_tempvltime(SYSCTL_HANDLER_ARGS)
234 {
235 	int error, val;
236 
237 	val = V_ip6_temp_valid_lifetime;
238 	error = sysctl_handle_int(oidp, &val, 0, req);
239 	if (error != 0 || !req->newptr)
240 		return (error);
241 	if (val < V_ip6_temp_preferred_lifetime)
242 		return (EINVAL);
243 	V_ip6_temp_valid_lifetime = val;
244 	return (0);
245 }
246 
247 int
248 ip6_log_ratelimit(void)
249 {
250 
251 	return (ppsratecheck(&V_ip6_log_last, &V_ip6_log_count,
252 	    V_ip6_log_interval));
253 }
254 
255 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_FORWARDING, forwarding,
256 	CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_forwarding), 0,
257 	"Enable forwarding of IPv6 packets between interfaces");
258 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_SENDREDIRECTS, redirect,
259 	CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_sendredirects), 0,
260 	"Send ICMPv6 redirects for unforwardable IPv6 packets");
261 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_DEFHLIM, hlim,
262 	CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_defhlim), 0,
263 	"Default hop limit to use for outgoing IPv6 packets");
264 SYSCTL_VNET_PCPUSTAT(_net_inet6_ip6, IPV6CTL_STATS, stats, struct ip6stat,
265 	ip6stat,
266 	"IP6 statistics (struct ip6stat, netinet6/ip6_var.h)");
267 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_ACCEPT_RTADV, accept_rtadv,
268 	CTLFLAG_VNET | CTLFLAG_RWTUN, &VNET_NAME(ip6_accept_rtadv), 0,
269 	"Default value of per-interface flag for accepting ICMPv6 RA messages");
270 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_NO_RADR, no_radr,
271 	CTLFLAG_VNET | CTLFLAG_RWTUN, &VNET_NAME(ip6_no_radr), 0,
272 	"Default value of per-interface flag to control whether routers "
273 	"sending ICMPv6 RA messages on that interface are added into the "
274 	"default router list");
275 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_NORBIT_RAIF, norbit_raif,
276 	CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_norbit_raif), 0,
277 	"Always set clear the R flag in ICMPv6 NA messages when accepting RA "
278 	"on the interface");
279 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_RFC6204W3, rfc6204w3,
280 	CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_rfc6204w3), 0,
281 	"Accept the default router list from ICMPv6 RA messages even "
282 	"when packet forwarding is enabled");
283 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_LOG_INTERVAL, log_interval,
284 	CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_log_interval), 0,
285 	"Frequency in seconds at which to log IPv6 forwarding errors");
286 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_HDRNESTLIMIT, hdrnestlimit,
287 	CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_hdrnestlimit), 0,
288 	"Default maximum number of IPv6 extension headers permitted on "
289 	"incoming IPv6 packets, 0 for no artificial limit");
290 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_DAD_COUNT, dad_count,
291 	CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_dad_count), 0,
292 	"Number of ICMPv6 NS messages sent during duplicate address detection");
293 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_AUTO_FLOWLABEL, auto_flowlabel,
294 	CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_auto_flowlabel), 0,
295 	"Provide an IPv6 flowlabel in outbound packets");
296 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_DEFMCASTHLIM, defmcasthlim,
297 	CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_defmcasthlim), 0,
298 	"Default hop limit for IPv6 multicast packets originating from this "
299 	"node");
300 SYSCTL_STRING(_net_inet6_ip6, IPV6CTL_KAME_VERSION, kame_version,
301 	CTLFLAG_RD, __KAME_VERSION, 0,
302 	"KAME version string");
303 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_USE_DEPRECATED, use_deprecated,
304 	CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_use_deprecated), 0,
305 	"Allow the use of addresses whose preferred lifetimes have expired");
306 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_RR_PRUNE, rr_prune,
307 	CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_rr_prune), 0,
308 	""); /* XXX unused */
309 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_USETEMPADDR, use_tempaddr,
310 	CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_use_tempaddr), 0,
311 	"Create RFC3041 temporary addresses for autoconfigured addresses");
312 SYSCTL_PROC(_net_inet6_ip6, IPV6CTL_TEMPPLTIME, temppltime,
313 	CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT,
314 	NULL, 0, sysctl_ip6_temppltime, "I",
315 	"Maximum preferred lifetime for temporary addresses");
316 SYSCTL_PROC(_net_inet6_ip6, IPV6CTL_TEMPVLTIME, tempvltime,
317 	CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT,
318 	NULL, 0, sysctl_ip6_tempvltime, "I",
319 	"Maximum valid lifetime for temporary addresses");
320 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_V6ONLY, v6only,
321 	CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_v6only), 0,
322 	"Restrict AF_INET6 sockets to IPv6 addresses only");
323 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_AUTO_LINKLOCAL, auto_linklocal,
324 	CTLFLAG_VNET | CTLFLAG_RWTUN, &VNET_NAME(ip6_auto_linklocal), 0,
325 	"Default value of per-interface flag for automatically adding an IPv6 "
326 	"link-local address to interfaces when attached");
327 SYSCTL_VNET_PCPUSTAT(_net_inet6_ip6, IPV6CTL_RIP6STATS, rip6stats,
328 	struct rip6stat, rip6stat,
329 	"Raw IP6 statistics (struct rip6stat, netinet6/raw_ip6.h)");
330 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_PREFER_TEMPADDR, prefer_tempaddr,
331 	CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_prefer_tempaddr), 0,
332 	"Prefer RFC3041 temporary addresses in source address selection");
333 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_USE_DEFAULTZONE, use_defaultzone,
334 	CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_use_defzone), 0,
335 	"Use the default scope zone when none is specified");
336 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_MCAST_PMTU, mcast_pmtu,
337 	CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ip6_mcast_pmtu), 0,
338 	"Enable path MTU discovery for multicast packets");
339 #ifdef IPSTEALTH
340 SYSCTL_INT(_net_inet6_ip6, IPV6CTL_STEALTH, stealth, CTLFLAG_VNET | CTLFLAG_RW,
341 	&VNET_NAME(ip6stealth), 0,
342 	"Forward IPv6 packets without decrementing their TTL");
343 #endif
344 SYSCTL_BOOL(_net_inet6_ip6, OID_AUTO,
345 	log_cannot_forward, CTLFLAG_VNET | CTLFLAG_RW,
346 	&VNET_NAME(ip6_log_cannot_forward), 1,
347 	"Log packets that cannot be forwarded");
348