in6_rmx.c revision 314667 
1/*-
2 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 * 3. Neither the name of the project nor the names of its contributors
14 *    may be used to endorse or promote products derived from this software
15 *    without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 *	$KAME: in6_rmx.c,v 1.11 2001/07/26 06:53:16 jinmei Exp $
30 */
31
32/*-
33 * Copyright 1994, 1995 Massachusetts Institute of Technology
34 *
35 * Permission to use, copy, modify, and distribute this software and
36 * its documentation for any purpose and without fee is hereby
37 * granted, provided that both the above copyright notice and this
38 * permission notice appear in all copies, that both the above
39 * copyright notice and this permission notice appear in all
40 * supporting documentation, and that the name of M.I.T. not be used
41 * in advertising or publicity pertaining to distribution of the
42 * software without specific, written prior permission.  M.I.T. makes
43 * no representations about the suitability of this software for any
44 * purpose.  It is provided "as is" without express or implied
45 * warranty.
46 *
47 * THIS SOFTWARE IS PROVIDED BY M.I.T. ``AS IS''.  M.I.T. DISCLAIMS
48 * ALL EXPRESS OR IMPLIED WARRANTIES WITH REGARD TO THIS SOFTWARE,
49 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
50 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT
51 * SHALL M.I.T. BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
52 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
53 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
54 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
55 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
56 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
57 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
58 * SUCH DAMAGE.
59 *
60 */
61
62#include <sys/cdefs.h>
63__FBSDID("$FreeBSD: stable/10/sys/netinet6/in6_rmx.c 314667 2017-03-04 13:03:31Z avg $");
64
65#include <sys/param.h>
66#include <sys/systm.h>
67#include <sys/kernel.h>
68#include <sys/lock.h>
69#include <sys/sysctl.h>
70#include <sys/queue.h>
71#include <sys/socket.h>
72#include <sys/socketvar.h>
73#include <sys/mbuf.h>
74#include <sys/rwlock.h>
75#include <sys/syslog.h>
76#include <sys/callout.h>
77
78#include <net/if.h>
79#include <net/route.h>
80
81#include <netinet/in.h>
82#include <netinet/ip_var.h>
83#include <netinet/in_var.h>
84
85#include <netinet/ip6.h>
86#include <netinet6/ip6_var.h>
87
88#include <netinet/icmp6.h>
89#include <netinet6/nd6.h>
90
91#include <netinet/tcp.h>
92#include <netinet/tcp_seq.h>
93#include <netinet/tcp_timer.h>
94#include <netinet/tcp_var.h>
95
96extern int	in6_inithead(void **head, int off);
97#ifdef VIMAGE
98extern int	in6_detachhead(void **head, int off);
99#endif
100
101/*
102 * Do what we need to do when inserting a route.
103 */
104static struct radix_node *
105in6_addroute(void *v_arg, void *n_arg, struct radix_node_head *head,
106    struct radix_node *treenodes)
107{
108	struct rtentry *rt = (struct rtentry *)treenodes;
109	struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)rt_key(rt);
110	struct radix_node *ret;
111
112	RADIX_NODE_HEAD_WLOCK_ASSERT(head);
113	if (IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr))
114		rt->rt_flags |= RTF_MULTICAST;
115
116	/*
117	 * A little bit of help for both IPv6 output and input:
118	 *   For local addresses, we make sure that RTF_LOCAL is set,
119	 *   with the thought that this might one day be used to speed up
120	 *   ip_input().
121	 *
122	 * We also mark routes to multicast addresses as such, because
123	 * it's easy to do and might be useful (but this is much more
124	 * dubious since it's so easy to inspect the address).  (This
125	 * is done above.)
126	 *
127	 * XXX
128	 * should elaborate the code.
129	 */
130	if (rt->rt_flags & RTF_HOST) {
131		if (IN6_ARE_ADDR_EQUAL(&satosin6(rt->rt_ifa->ifa_addr)
132					->sin6_addr,
133				       &sin6->sin6_addr)) {
134			rt->rt_flags |= RTF_LOCAL;
135		}
136	}
137
138	if (!rt->rt_mtu && rt->rt_ifp)
139		rt->rt_mtu = IN6_LINKMTU(rt->rt_ifp);
140
141	ret = rn_addroute(v_arg, n_arg, head, treenodes);
142	if (ret == NULL) {
143		struct rtentry *rt2;
144		/*
145		 * We are trying to add a net route, but can't.
146		 * The following case should be allowed, so we'll make a
147		 * special check for this:
148		 *	Two IPv6 addresses with the same prefix is assigned
149		 *	to a single interrface.
150		 *	# ifconfig if0 inet6 3ffe:0501::1 prefix 64 alias (*1)
151		 *	# ifconfig if0 inet6 3ffe:0501::2 prefix 64 alias (*2)
152		 *	In this case, (*1) and (*2) want to add the same
153		 *	net route entry, 3ffe:0501:: -> if0.
154		 *	This case should not raise an error.
155		 */
156		rt2 = in6_rtalloc1((struct sockaddr *)sin6, 0, RTF_RNH_LOCKED,
157		    rt->rt_fibnum);
158		if (rt2) {
159			if (((rt2->rt_flags & (RTF_HOST|RTF_GATEWAY)) == 0)
160			 && rt2->rt_gateway
161			 && rt2->rt_gateway->sa_family == AF_LINK
162			 && rt2->rt_ifp == rt->rt_ifp) {
163				ret = rt2->rt_nodes;
164			}
165			RTFREE_LOCKED(rt2);
166		}
167	}
168	return (ret);
169}
170
171SYSCTL_DECL(_net_inet6_ip6);
172
173static VNET_DEFINE(int, rtq_toomany6) = 128;
174	/* 128 cached routes is ``too many'' */
175#define	V_rtq_toomany6			VNET(rtq_toomany6)
176SYSCTL_VNET_INT(_net_inet6_ip6, IPV6CTL_RTMAXCACHE, rtmaxcache, CTLFLAG_RW,
177    &VNET_NAME(rtq_toomany6) , 0, "");
178
179struct rtqk_arg {
180	struct radix_node_head *rnh;
181	int mode;
182	int updating;
183	int draining;
184	int killed;
185	int found;
186	time_t nextstop;
187};
188
189/*
190 * Age old PMTUs.
191 */
192struct mtuex_arg {
193	struct radix_node_head *rnh;
194	time_t nextstop;
195};
196static VNET_DEFINE(struct callout, rtq_mtutimer);
197#define	V_rtq_mtutimer			VNET(rtq_mtutimer)
198
199static int
200in6_mtuexpire(struct radix_node *rn, void *rock)
201{
202	struct rtentry *rt = (struct rtentry *)rn;
203	struct mtuex_arg *ap = rock;
204
205	/* sanity */
206	if (!rt)
207		panic("rt == NULL in in6_mtuexpire");
208
209	if (rt->rt_expire && !(rt->rt_flags & RTF_PROBEMTU)) {
210		if (rt->rt_expire <= time_uptime) {
211			rt->rt_flags |= RTF_PROBEMTU;
212		} else {
213			ap->nextstop = lmin(ap->nextstop, rt->rt_expire);
214		}
215	}
216
217	return 0;
218}
219
220#define	MTUTIMO_DEFAULT	(60*1)
221
222static void
223in6_mtutimo_one(struct radix_node_head *rnh)
224{
225	struct mtuex_arg arg;
226
227	arg.rnh = rnh;
228	arg.nextstop = time_uptime + MTUTIMO_DEFAULT;
229	RADIX_NODE_HEAD_LOCK(rnh);
230	rnh->rnh_walktree(rnh, in6_mtuexpire, &arg);
231	RADIX_NODE_HEAD_UNLOCK(rnh);
232}
233
234static void
235in6_mtutimo(void *rock)
236{
237	CURVNET_SET_QUIET((struct vnet *) rock);
238	struct radix_node_head *rnh;
239	struct timeval atv;
240	u_int fibnum;
241
242	for (fibnum = 0; fibnum < rt_numfibs; fibnum++) {
243		rnh = rt_tables_get_rnh(fibnum, AF_INET6);
244		if (rnh != NULL)
245			in6_mtutimo_one(rnh);
246	}
247
248	atv.tv_sec = MTUTIMO_DEFAULT;
249	atv.tv_usec = 0;
250	callout_reset(&V_rtq_mtutimer, tvtohz(&atv), in6_mtutimo, rock);
251	CURVNET_RESTORE();
252}
253
254/*
255 * Initialize our routing tree.
256 * XXX MRT When off == 0, we are being called from vfs_export.c
257 * so just set up their table and leave. (we know what the correct
258 * value should be so just use that).. FIX AFTER RELENG_7 is MFC'd
259 * see also comments in in_inithead() vfs_export.c and domain.h
260 */
261static VNET_DEFINE(int, _in6_rt_was_here);
262#define	V__in6_rt_was_here	VNET(_in6_rt_was_here)
263
264int
265in6_inithead(void **head, int off)
266{
267	struct radix_node_head *rnh;
268
269	if (!rn_inithead(head, offsetof(struct sockaddr_in6, sin6_addr) << 3))
270		return 0;		/* See above */
271
272	if (off == 0)		/* See above */
273		return 1;	/* only do the rest for the real thing */
274
275	rnh = *head;
276	rnh->rnh_addaddr = in6_addroute;
277
278	if (V__in6_rt_was_here == 0) {
279		callout_init(&V_rtq_mtutimer, 1);
280		in6_mtutimo(curvnet);	/* kick off timeout first time */
281		V__in6_rt_was_here = 1;
282	}
283
284	return 1;
285}
286
287#ifdef VIMAGE
288int
289in6_detachhead(void **head, int off)
290{
291
292	callout_drain(&V_rtq_mtutimer);
293	return (rn_detachhead(head));
294}
295#endif
296
297/*
298 * Extended API for IPv6 FIB support.
299 */
300void
301in6_rtredirect(struct sockaddr *dst, struct sockaddr *gw, struct sockaddr *nm,
302    int flags, struct sockaddr *src, u_int fibnum)
303{
304
305	rtredirect_fib(dst, gw, nm, flags, src, fibnum);
306}
307
308int
309in6_rtrequest(int req, struct sockaddr *dst, struct sockaddr *gw,
310    struct sockaddr *mask, int flags, struct rtentry **ret_nrt, u_int fibnum)
311{
312
313	return (rtrequest_fib(req, dst, gw, mask, flags, ret_nrt, fibnum));
314}
315
316void
317in6_rtalloc(struct route_in6 *ro, u_int fibnum)
318{
319
320	rtalloc_ign_fib((struct route *)ro, 0ul, fibnum);
321}
322
323void
324in6_rtalloc_ign(struct route_in6 *ro, u_long ignflags, u_int fibnum)
325{
326
327	rtalloc_ign_fib((struct route *)ro, ignflags, fibnum);
328}
329
330struct rtentry *
331in6_rtalloc1(struct sockaddr *dst, int report, u_long ignflags, u_int fibnum)
332{
333
334	return (rtalloc1_fib(dst, report, ignflags, fibnum));
335}
336