in6_rmx.c revision 286458 
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: head/sys/netinet6/in6_rmx.c 286458 2015-08-08 18:14:59Z melifaro $");
64
65#include <sys/param.h>
66#include <sys/systm.h>
67#include <sys/kernel.h>
68#include <sys/lock.h>
69#include <sys/queue.h>
70#include <sys/socket.h>
71#include <sys/socketvar.h>
72#include <sys/mbuf.h>
73#include <sys/rwlock.h>
74#include <sys/syslog.h>
75#include <sys/callout.h>
76
77#include <net/if.h>
78#include <net/if_var.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_ifp != NULL) {
139
140		/*
141		 * Check route MTU:
142		 * inherit interface MTU if not set or
143		 * check if MTU is too large.
144		 */
145		if (rt->rt_mtu == 0) {
146			rt->rt_mtu = IN6_LINKMTU(rt->rt_ifp);
147		} else if (rt->rt_mtu > IN6_LINKMTU(rt->rt_ifp))
148			rt->rt_mtu = IN6_LINKMTU(rt->rt_ifp);
149	}
150
151	ret = rn_addroute(v_arg, n_arg, head, treenodes);
152	if (ret == NULL) {
153		struct rtentry *rt2;
154		/*
155		 * We are trying to add a net route, but can't.
156		 * The following case should be allowed, so we'll make a
157		 * special check for this:
158		 *	Two IPv6 addresses with the same prefix is assigned
159		 *	to a single interrface.
160		 *	# ifconfig if0 inet6 3ffe:0501::1 prefix 64 alias (*1)
161		 *	# ifconfig if0 inet6 3ffe:0501::2 prefix 64 alias (*2)
162		 *	In this case, (*1) and (*2) want to add the same
163		 *	net route entry, 3ffe:0501:: -> if0.
164		 *	This case should not raise an error.
165		 */
166		rt2 = in6_rtalloc1((struct sockaddr *)sin6, 0, RTF_RNH_LOCKED,
167		    rt->rt_fibnum);
168		if (rt2) {
169			if (((rt2->rt_flags & (RTF_HOST|RTF_GATEWAY)) == 0)
170			 && rt2->rt_gateway
171			 && rt2->rt_gateway->sa_family == AF_LINK
172			 && rt2->rt_ifp == rt->rt_ifp) {
173				ret = rt2->rt_nodes;
174			}
175			RTFREE_LOCKED(rt2);
176		}
177	}
178	return (ret);
179}
180
181/*
182 * Age old PMTUs.
183 */
184struct mtuex_arg {
185	struct radix_node_head *rnh;
186	time_t nextstop;
187};
188static VNET_DEFINE(struct callout, rtq_mtutimer);
189#define	V_rtq_mtutimer			VNET(rtq_mtutimer)
190
191static int
192in6_mtuexpire(struct rtentry *rt, void *rock)
193{
194	struct mtuex_arg *ap = rock;
195
196	if (rt->rt_expire && !(rt->rt_flags & RTF_PROBEMTU)) {
197		if (rt->rt_expire <= time_uptime) {
198			rt->rt_flags |= RTF_PROBEMTU;
199		} else {
200			ap->nextstop = lmin(ap->nextstop, rt->rt_expire);
201		}
202	}
203
204	return (0);
205}
206
207#define	MTUTIMO_DEFAULT	(60*1)
208
209static void
210in6_mtutimo_setwa(struct radix_node_head *rnh, uint32_t fibum, int af, void *_arg)
211{
212	struct mtuex_arg *arg;
213
214	arg = (struct mtuex_arg *)_arg;
215
216	arg->rnh = rnh;
217}
218
219static void
220in6_mtutimo(void *rock)
221{
222	CURVNET_SET_QUIET((struct vnet *) rock);
223	struct timeval atv;
224	struct mtuex_arg arg;
225
226	rt_foreach_fib(AF_INET6, in6_mtutimo_setwa, in6_mtuexpire, &arg);
227
228	atv.tv_sec = MTUTIMO_DEFAULT;
229	atv.tv_usec = 0;
230	callout_reset(&V_rtq_mtutimer, tvtohz(&atv), in6_mtutimo, rock);
231	CURVNET_RESTORE();
232}
233
234/*
235 * Initialize our routing tree.
236 */
237static VNET_DEFINE(int, _in6_rt_was_here);
238#define	V__in6_rt_was_here	VNET(_in6_rt_was_here)
239
240int
241in6_inithead(void **head, int off)
242{
243	struct radix_node_head *rnh;
244
245	if (!rn_inithead(head, offsetof(struct sockaddr_in6, sin6_addr) << 3))
246		return (0);
247
248	rnh = *head;
249	RADIX_NODE_HEAD_LOCK_INIT(rnh);
250
251	rnh->rnh_addaddr = in6_addroute;
252
253	if (V__in6_rt_was_here == 0) {
254		callout_init(&V_rtq_mtutimer, 1);
255		in6_mtutimo(curvnet);	/* kick off timeout first time */
256		V__in6_rt_was_here = 1;
257	}
258
259	return (1);
260}
261
262#ifdef VIMAGE
263int
264in6_detachhead(void **head, int off)
265{
266
267	callout_drain(&V_rtq_mtutimer);
268	return (1);
269}
270#endif
271
272/*
273 * Extended API for IPv6 FIB support.
274 */
275void
276in6_rtredirect(struct sockaddr *dst, struct sockaddr *gw, struct sockaddr *nm,
277    int flags, struct sockaddr *src, u_int fibnum)
278{
279
280	rtredirect_fib(dst, gw, nm, flags, src, fibnum);
281}
282
283int
284in6_rtrequest(int req, struct sockaddr *dst, struct sockaddr *gw,
285    struct sockaddr *mask, int flags, struct rtentry **ret_nrt, u_int fibnum)
286{
287
288	return (rtrequest_fib(req, dst, gw, mask, flags, ret_nrt, fibnum));
289}
290
291void
292in6_rtalloc(struct route_in6 *ro, u_int fibnum)
293{
294
295	rtalloc_ign_fib((struct route *)ro, 0ul, fibnum);
296}
297
298void
299in6_rtalloc_ign(struct route_in6 *ro, u_long ignflags, u_int fibnum)
300{
301
302	rtalloc_ign_fib((struct route *)ro, ignflags, fibnum);
303}
304
305struct rtentry *
306in6_rtalloc1(struct sockaddr *dst, int report, u_long ignflags, u_int fibnum)
307{
308
309	return (rtalloc1_fib(dst, report, ignflags, fibnum));
310}
311