1/*
2 * Copyright 1994, 1995 Massachusetts Institute of Technology
3 *
4 * Permission to use, copy, modify, and distribute this software and
5 * its documentation for any purpose and without fee is hereby
6 * granted, provided that both the above copyright notice and this
7 * permission notice appear in all copies, that both the above
8 * copyright notice and this permission notice appear in all
9 * supporting documentation, and that the name of M.I.T. not be used
10 * in advertising or publicity pertaining to distribution of the
11 * software without specific, written prior permission. M.I.T. makes
12 * no representations about the suitability of this software for any
13 * purpose. It is provided "as is" without express or implied
14 * warranty.
15 *
16 * THIS SOFTWARE IS PROVIDED BY M.I.T. ``AS IS''. M.I.T. DISCLAIMS
17 * ALL EXPRESS OR IMPLIED WARRANTIES WITH REGARD TO THIS SOFTWARE,
18 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
19 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT
20 * SHALL M.I.T. BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
21 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
22 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
23 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
24 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
25 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
26 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
| 1/*
2 * Copyright 1994, 1995 Massachusetts Institute of Technology
3 *
4 * Permission to use, copy, modify, and distribute this software and
5 * its documentation for any purpose and without fee is hereby
6 * granted, provided that both the above copyright notice and this
7 * permission notice appear in all copies, that both the above
8 * copyright notice and this permission notice appear in all
9 * supporting documentation, and that the name of M.I.T. not be used
10 * in advertising or publicity pertaining to distribution of the
11 * software without specific, written prior permission. M.I.T. makes
12 * no representations about the suitability of this software for any
13 * purpose. It is provided "as is" without express or implied
14 * warranty.
15 *
16 * THIS SOFTWARE IS PROVIDED BY M.I.T. ``AS IS''. M.I.T. DISCLAIMS
17 * ALL EXPRESS OR IMPLIED WARRANTIES WITH REGARD TO THIS SOFTWARE,
18 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
19 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT
20 * SHALL M.I.T. BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
21 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
22 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
23 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
24 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
25 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
26 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
|
29 * $Id: in_rmx.c,v 1.34 1998/03/30 09:52:46 phk Exp $
| 29 * $Id: in_rmx.c,v 1.35 1998/08/05 16:59:20 bde Exp $
|
30 */
31
32/*
33 * This code does two things necessary for the enhanced TCP metrics to
34 * function in a useful manner:
35 * 1) It marks all non-host routes as `cloning', thus ensuring that
36 * every actual reference to such a route actually gets turned
37 * into a reference to a host route to the specific destination
38 * requested.
39 * 2) When such routes lose all their references, it arranges for them
40 * to be deleted in some random collection of circumstances, so that
41 * a large quantity of stale routing data is not kept in kernel memory
42 * indefinitely. See in_rtqtimo() below for the exact mechanism.
43 */
44
45#include <sys/param.h>
46#include <sys/systm.h>
47#include <sys/kernel.h>
48#include <sys/sysctl.h>
49#include <sys/socket.h>
50#include <sys/mbuf.h>
51#include <sys/syslog.h>
52
53#include <net/if.h>
54#include <net/route.h>
55#include <netinet/in.h>
56#include <netinet/in_var.h>
57
58extern int in_inithead __P((void **head, int off));
59
60#define RTPRF_OURS RTF_PROTO3 /* set on routes we manage */
61
62/*
63 * Do what we need to do when inserting a route.
64 */
65static struct radix_node *
66in_addroute(void *v_arg, void *n_arg, struct radix_node_head *head,
67 struct radix_node *treenodes)
68{
69 struct rtentry *rt = (struct rtentry *)treenodes;
70 struct sockaddr_in *sin = (struct sockaddr_in *)rt_key(rt);
71 struct radix_node *ret;
72
73 /*
74 * For IP, all unicast non-host routes are automatically cloning.
75 */
76 if(IN_MULTICAST(ntohl(sin->sin_addr.s_addr)))
77 rt->rt_flags |= RTF_MULTICAST;
78
79 if(!(rt->rt_flags & (RTF_HOST | RTF_CLONING | RTF_MULTICAST))) {
80 rt->rt_flags |= RTF_PRCLONING;
81 }
82
83 /*
84 * A little bit of help for both IP output and input:
85 * For host routes, we make sure that RTF_BROADCAST
86 * is set for anything that looks like a broadcast address.
87 * This way, we can avoid an expensive call to in_broadcast()
88 * in ip_output() most of the time (because the route passed
89 * to ip_output() is almost always a host route).
90 *
91 * We also do the same for local addresses, with the thought
92 * that this might one day be used to speed up ip_input().
93 *
94 * We also mark routes to multicast addresses as such, because
95 * it's easy to do and might be useful (but this is much more
96 * dubious since it's so easy to inspect the address). (This
97 * is done above.)
98 */
99 if (rt->rt_flags & RTF_HOST) {
100 if (in_broadcast(sin->sin_addr, rt->rt_ifp)) {
101 rt->rt_flags |= RTF_BROADCAST;
102 } else {
103#define satosin(sa) ((struct sockaddr_in *)sa)
104 if (satosin(rt->rt_ifa->ifa_addr)->sin_addr.s_addr
105 == sin->sin_addr.s_addr)
106 rt->rt_flags |= RTF_LOCAL;
107#undef satosin
108 }
109 }
110
111 if (!rt->rt_rmx.rmx_mtu && !(rt->rt_rmx.rmx_locks & RTV_MTU)
112 && rt->rt_ifp)
113 rt->rt_rmx.rmx_mtu = rt->rt_ifp->if_mtu;
114
115 ret = rn_addroute(v_arg, n_arg, head, treenodes);
116 if (ret == NULL && rt->rt_flags & RTF_HOST) {
117 struct rtentry *rt2;
118 /*
119 * We are trying to add a host route, but can't.
120 * Find out if it is because of an
121 * ARP entry and delete it if so.
122 */
123 rt2 = rtalloc1((struct sockaddr *)sin, 0,
124 RTF_CLONING | RTF_PRCLONING);
125 if (rt2) {
126 if (rt2->rt_flags & RTF_LLINFO &&
127 rt2->rt_flags & RTF_HOST &&
128 rt2->rt_gateway &&
129 rt2->rt_gateway->sa_family == AF_LINK) {
130 rtrequest(RTM_DELETE,
131 (struct sockaddr *)rt_key(rt2),
132 rt2->rt_gateway,
133 rt_mask(rt2), rt2->rt_flags, 0);
134 ret = rn_addroute(v_arg, n_arg, head,
135 treenodes);
136 }
137 RTFREE(rt2);
138 }
139 }
140 return ret;
141}
142
143/*
144 * This code is the inverse of in_clsroute: on first reference, if we
145 * were managing the route, stop doing so and set the expiration timer
146 * back off again.
147 */
148static struct radix_node *
149in_matroute(void *v_arg, struct radix_node_head *head)
150{
151 struct radix_node *rn = rn_match(v_arg, head);
152 struct rtentry *rt = (struct rtentry *)rn;
153
154 if(rt && rt->rt_refcnt == 0) { /* this is first reference */
155 if(rt->rt_flags & RTPRF_OURS) {
156 rt->rt_flags &= ~RTPRF_OURS;
157 rt->rt_rmx.rmx_expire = 0;
158 }
159 }
160 return rn;
161}
162
163static int rtq_reallyold = 60*60;
164 /* one hour is ``really old'' */
| 30 */
31
32/*
33 * This code does two things necessary for the enhanced TCP metrics to
34 * function in a useful manner:
35 * 1) It marks all non-host routes as `cloning', thus ensuring that
36 * every actual reference to such a route actually gets turned
37 * into a reference to a host route to the specific destination
38 * requested.
39 * 2) When such routes lose all their references, it arranges for them
40 * to be deleted in some random collection of circumstances, so that
41 * a large quantity of stale routing data is not kept in kernel memory
42 * indefinitely. See in_rtqtimo() below for the exact mechanism.
43 */
44
45#include <sys/param.h>
46#include <sys/systm.h>
47#include <sys/kernel.h>
48#include <sys/sysctl.h>
49#include <sys/socket.h>
50#include <sys/mbuf.h>
51#include <sys/syslog.h>
52
53#include <net/if.h>
54#include <net/route.h>
55#include <netinet/in.h>
56#include <netinet/in_var.h>
57
58extern int in_inithead __P((void **head, int off));
59
60#define RTPRF_OURS RTF_PROTO3 /* set on routes we manage */
61
62/*
63 * Do what we need to do when inserting a route.
64 */
65static struct radix_node *
66in_addroute(void *v_arg, void *n_arg, struct radix_node_head *head,
67 struct radix_node *treenodes)
68{
69 struct rtentry *rt = (struct rtentry *)treenodes;
70 struct sockaddr_in *sin = (struct sockaddr_in *)rt_key(rt);
71 struct radix_node *ret;
72
73 /*
74 * For IP, all unicast non-host routes are automatically cloning.
75 */
76 if(IN_MULTICAST(ntohl(sin->sin_addr.s_addr)))
77 rt->rt_flags |= RTF_MULTICAST;
78
79 if(!(rt->rt_flags & (RTF_HOST | RTF_CLONING | RTF_MULTICAST))) {
80 rt->rt_flags |= RTF_PRCLONING;
81 }
82
83 /*
84 * A little bit of help for both IP output and input:
85 * For host routes, we make sure that RTF_BROADCAST
86 * is set for anything that looks like a broadcast address.
87 * This way, we can avoid an expensive call to in_broadcast()
88 * in ip_output() most of the time (because the route passed
89 * to ip_output() is almost always a host route).
90 *
91 * We also do the same for local addresses, with the thought
92 * that this might one day be used to speed up ip_input().
93 *
94 * We also mark routes to multicast addresses as such, because
95 * it's easy to do and might be useful (but this is much more
96 * dubious since it's so easy to inspect the address). (This
97 * is done above.)
98 */
99 if (rt->rt_flags & RTF_HOST) {
100 if (in_broadcast(sin->sin_addr, rt->rt_ifp)) {
101 rt->rt_flags |= RTF_BROADCAST;
102 } else {
103#define satosin(sa) ((struct sockaddr_in *)sa)
104 if (satosin(rt->rt_ifa->ifa_addr)->sin_addr.s_addr
105 == sin->sin_addr.s_addr)
106 rt->rt_flags |= RTF_LOCAL;
107#undef satosin
108 }
109 }
110
111 if (!rt->rt_rmx.rmx_mtu && !(rt->rt_rmx.rmx_locks & RTV_MTU)
112 && rt->rt_ifp)
113 rt->rt_rmx.rmx_mtu = rt->rt_ifp->if_mtu;
114
115 ret = rn_addroute(v_arg, n_arg, head, treenodes);
116 if (ret == NULL && rt->rt_flags & RTF_HOST) {
117 struct rtentry *rt2;
118 /*
119 * We are trying to add a host route, but can't.
120 * Find out if it is because of an
121 * ARP entry and delete it if so.
122 */
123 rt2 = rtalloc1((struct sockaddr *)sin, 0,
124 RTF_CLONING | RTF_PRCLONING);
125 if (rt2) {
126 if (rt2->rt_flags & RTF_LLINFO &&
127 rt2->rt_flags & RTF_HOST &&
128 rt2->rt_gateway &&
129 rt2->rt_gateway->sa_family == AF_LINK) {
130 rtrequest(RTM_DELETE,
131 (struct sockaddr *)rt_key(rt2),
132 rt2->rt_gateway,
133 rt_mask(rt2), rt2->rt_flags, 0);
134 ret = rn_addroute(v_arg, n_arg, head,
135 treenodes);
136 }
137 RTFREE(rt2);
138 }
139 }
140 return ret;
141}
142
143/*
144 * This code is the inverse of in_clsroute: on first reference, if we
145 * were managing the route, stop doing so and set the expiration timer
146 * back off again.
147 */
148static struct radix_node *
149in_matroute(void *v_arg, struct radix_node_head *head)
150{
151 struct radix_node *rn = rn_match(v_arg, head);
152 struct rtentry *rt = (struct rtentry *)rn;
153
154 if(rt && rt->rt_refcnt == 0) { /* this is first reference */
155 if(rt->rt_flags & RTPRF_OURS) {
156 rt->rt_flags &= ~RTPRF_OURS;
157 rt->rt_rmx.rmx_expire = 0;
158 }
159 }
160 return rn;
161}
162
163static int rtq_reallyold = 60*60;
164 /* one hour is ``really old'' */
|
165SYSCTL_INT(_net_inet_ip, IPCTL_RTEXPIRE, rtexpire,
166 CTLFLAG_RW, &rtq_reallyold , 0, "");
| 165SYSCTL_INT(_net_inet_ip, IPCTL_RTEXPIRE, rtexpire, CTLFLAG_RW,
166 &rtq_reallyold , 0,
167 "Default expiration time on dynamically learned routes");
|
167
168static int rtq_minreallyold = 10;
169 /* never automatically crank down to less */
| 168
169static int rtq_minreallyold = 10;
170 /* never automatically crank down to less */
|
170SYSCTL_INT(_net_inet_ip, IPCTL_RTMINEXPIRE, rtminexpire,
171 CTLFLAG_RW, &rtq_minreallyold , 0, "");
| 171SYSCTL_INT(_net_inet_ip, IPCTL_RTMINEXPIRE, rtminexpire, CTLFLAG_RW,
172 &rtq_minreallyold , 0,
173 "Minimum time to attempt to hold onto dynamically learned routes");
|
172
173static int rtq_toomany = 128;
174 /* 128 cached routes is ``too many'' */
| 174
175static int rtq_toomany = 128;
176 /* 128 cached routes is ``too many'' */
|
175SYSCTL_INT(_net_inet_ip, IPCTL_RTMAXCACHE, rtmaxcache,
176 CTLFLAG_RW, &rtq_toomany , 0, "");
177
| 177SYSCTL_INT(_net_inet_ip, IPCTL_RTMAXCACHE, rtmaxcache, CTLFLAG_RW,
178 &rtq_toomany , 0, "Upper limit on dynamically learned routes");
|
178
179/*
180 * On last reference drop, mark the route as belong to us so that it can be
181 * timed out.
182 */
183static void
184in_clsroute(struct radix_node *rn, struct radix_node_head *head)
185{
186 struct rtentry *rt = (struct rtentry *)rn;
187
188 if(!(rt->rt_flags & RTF_UP))
189 return; /* prophylactic measures */
190
191 if((rt->rt_flags & (RTF_LLINFO | RTF_HOST)) != RTF_HOST)
192 return;
193
194 if((rt->rt_flags & (RTF_WASCLONED | RTPRF_OURS))
195 != RTF_WASCLONED)
196 return;
197
198 /*
199 * As requested by David Greenman:
200 * If rtq_reallyold is 0, just delete the route without
201 * waiting for a timeout cycle to kill it.
202 */
203 if(rtq_reallyold != 0) {
204 rt->rt_flags |= RTPRF_OURS;
205 rt->rt_rmx.rmx_expire = time_second + rtq_reallyold;
206 } else {
207 rtrequest(RTM_DELETE,
208 (struct sockaddr *)rt_key(rt),
209 rt->rt_gateway, rt_mask(rt),
210 rt->rt_flags, 0);
211 }
212}
213
214struct rtqk_arg {
215 struct radix_node_head *rnh;
216 int draining;
217 int killed;
218 int found;
219 int updating;
220 time_t nextstop;
221};
222
223/*
224 * Get rid of old routes. When draining, this deletes everything, even when
225 * the timeout is not expired yet. When updating, this makes sure that
226 * nothing has a timeout longer than the current value of rtq_reallyold.
227 */
228static int
229in_rtqkill(struct radix_node *rn, void *rock)
230{
231 struct rtqk_arg *ap = rock;
232 struct rtentry *rt = (struct rtentry *)rn;
233 int err;
234
235 if(rt->rt_flags & RTPRF_OURS) {
236 ap->found++;
237
238 if(ap->draining || rt->rt_rmx.rmx_expire <= time_second) {
239 if(rt->rt_refcnt > 0)
240 panic("rtqkill route really not free");
241
242 err = rtrequest(RTM_DELETE,
243 (struct sockaddr *)rt_key(rt),
244 rt->rt_gateway, rt_mask(rt),
245 rt->rt_flags, 0);
246 if(err) {
247 log(LOG_WARNING, "in_rtqkill: error %d\n", err);
248 } else {
249 ap->killed++;
250 }
251 } else {
252 if(ap->updating
253 && (rt->rt_rmx.rmx_expire - time_second
254 > rtq_reallyold)) {
255 rt->rt_rmx.rmx_expire = time_second
256 + rtq_reallyold;
257 }
258 ap->nextstop = lmin(ap->nextstop,
259 rt->rt_rmx.rmx_expire);
260 }
261 }
262
263 return 0;
264}
265
266#define RTQ_TIMEOUT 60*10 /* run no less than once every ten minutes */
267static int rtq_timeout = RTQ_TIMEOUT;
268
269static void
270in_rtqtimo(void *rock)
271{
272 struct radix_node_head *rnh = rock;
273 struct rtqk_arg arg;
274 struct timeval atv;
275 static time_t last_adjusted_timeout = 0;
276 int s;
277
278 arg.found = arg.killed = 0;
279 arg.rnh = rnh;
280 arg.nextstop = time_second + rtq_timeout;
281 arg.draining = arg.updating = 0;
282 s = splnet();
283 rnh->rnh_walktree(rnh, in_rtqkill, &arg);
284 splx(s);
285
286 /*
287 * Attempt to be somewhat dynamic about this:
288 * If there are ``too many'' routes sitting around taking up space,
289 * then crank down the timeout, and see if we can't make some more
290 * go away. However, we make sure that we will never adjust more
291 * than once in rtq_timeout seconds, to keep from cranking down too
292 * hard.
293 */
294 if((arg.found - arg.killed > rtq_toomany)
295 && (time_second - last_adjusted_timeout >= rtq_timeout)
296 && rtq_reallyold > rtq_minreallyold) {
297 rtq_reallyold = 2*rtq_reallyold / 3;
298 if(rtq_reallyold < rtq_minreallyold) {
299 rtq_reallyold = rtq_minreallyold;
300 }
301
302 last_adjusted_timeout = time_second;
303#ifdef DIAGNOSTIC
304 log(LOG_DEBUG, "in_rtqtimo: adjusted rtq_reallyold to %d\n",
305 rtq_reallyold);
306#endif
307 arg.found = arg.killed = 0;
308 arg.updating = 1;
309 s = splnet();
310 rnh->rnh_walktree(rnh, in_rtqkill, &arg);
311 splx(s);
312 }
313
314 atv.tv_usec = 0;
315 atv.tv_sec = arg.nextstop - time_second;
316 timeout(in_rtqtimo, rock, tvtohz(&atv));
317}
318
319void
320in_rtqdrain(void)
321{
322 struct radix_node_head *rnh = rt_tables[AF_INET];
323 struct rtqk_arg arg;
324 int s;
325 arg.found = arg.killed = 0;
326 arg.rnh = rnh;
327 arg.nextstop = 0;
328 arg.draining = 1;
329 arg.updating = 0;
330 s = splnet();
331 rnh->rnh_walktree(rnh, in_rtqkill, &arg);
332 splx(s);
333}
334
335/*
336 * Initialize our routing tree.
337 */
338int
339in_inithead(void **head, int off)
340{
341 struct radix_node_head *rnh;
342
343 if(!rn_inithead(head, off))
344 return 0;
345
346 if(head != (void **)&rt_tables[AF_INET]) /* BOGUS! */
347 return 1; /* only do this for the real routing table */
348
349 rnh = *head;
350 rnh->rnh_addaddr = in_addroute;
351 rnh->rnh_matchaddr = in_matroute;
352 rnh->rnh_close = in_clsroute;
353 in_rtqtimo(rnh); /* kick off timeout first time */
354 return 1;
355}
356
357
358/*
359 * This zaps old routes when the interface goes down.
360 * Currently it doesn't delete static routes; there are
361 * arguments one could make for both behaviors. For the moment,
362 * we will adopt the Principle of Least Surprise and leave them
363 * alone (with the knowledge that this will not be enough for some
364 * people). The ones we really want to get rid of are things like ARP
365 * entries, since the user might down the interface, walk over to a completely
366 * different network, and plug back in.
367 */
368struct in_ifadown_arg {
369 struct radix_node_head *rnh;
370 struct ifaddr *ifa;
371};
372
373static int
374in_ifadownkill(struct radix_node *rn, void *xap)
375{
376 struct in_ifadown_arg *ap = xap;
377 struct rtentry *rt = (struct rtentry *)rn;
378 int err;
379
380 if (rt->rt_ifa == ap->ifa && !(rt->rt_flags & RTF_STATIC)) {
381 /*
382 * We need to disable the automatic prune that happens
383 * in this case in rtrequest() because it will blow
384 * away the pointers that rn_walktree() needs in order
385 * continue our descent. We will end up deleting all
386 * the routes that rtrequest() would have in any case,
387 * so that behavior is not needed there.
388 */
389 rt->rt_flags &= ~RTF_PRCLONING;
390 err = rtrequest(RTM_DELETE, (struct sockaddr *)rt_key(rt),
391 rt->rt_gateway, rt_mask(rt), rt->rt_flags, 0);
392 if (err) {
393 log(LOG_WARNING, "in_ifadownkill: error %d\n", err);
394 }
395 }
396 return 0;
397}
398
399int
400in_ifadown(struct ifaddr *ifa)
401{
402 struct in_ifadown_arg arg;
403 struct radix_node_head *rnh;
404
405 if (ifa->ifa_addr->sa_family != AF_INET)
406 return 1;
407
408 arg.rnh = rnh = rt_tables[AF_INET];
409 arg.ifa = ifa;
410 rnh->rnh_walktree(rnh, in_ifadownkill, &arg);
411 ifa->ifa_flags &= ~IFA_ROUTE;
412 return 0;
413}
| 179
180/*
181 * On last reference drop, mark the route as belong to us so that it can be
182 * timed out.
183 */
184static void
185in_clsroute(struct radix_node *rn, struct radix_node_head *head)
186{
187 struct rtentry *rt = (struct rtentry *)rn;
188
189 if(!(rt->rt_flags & RTF_UP))
190 return; /* prophylactic measures */
191
192 if((rt->rt_flags & (RTF_LLINFO | RTF_HOST)) != RTF_HOST)
193 return;
194
195 if((rt->rt_flags & (RTF_WASCLONED | RTPRF_OURS))
196 != RTF_WASCLONED)
197 return;
198
199 /*
200 * As requested by David Greenman:
201 * If rtq_reallyold is 0, just delete the route without
202 * waiting for a timeout cycle to kill it.
203 */
204 if(rtq_reallyold != 0) {
205 rt->rt_flags |= RTPRF_OURS;
206 rt->rt_rmx.rmx_expire = time_second + rtq_reallyold;
207 } else {
208 rtrequest(RTM_DELETE,
209 (struct sockaddr *)rt_key(rt),
210 rt->rt_gateway, rt_mask(rt),
211 rt->rt_flags, 0);
212 }
213}
214
215struct rtqk_arg {
216 struct radix_node_head *rnh;
217 int draining;
218 int killed;
219 int found;
220 int updating;
221 time_t nextstop;
222};
223
224/*
225 * Get rid of old routes. When draining, this deletes everything, even when
226 * the timeout is not expired yet. When updating, this makes sure that
227 * nothing has a timeout longer than the current value of rtq_reallyold.
228 */
229static int
230in_rtqkill(struct radix_node *rn, void *rock)
231{
232 struct rtqk_arg *ap = rock;
233 struct rtentry *rt = (struct rtentry *)rn;
234 int err;
235
236 if(rt->rt_flags & RTPRF_OURS) {
237 ap->found++;
238
239 if(ap->draining || rt->rt_rmx.rmx_expire <= time_second) {
240 if(rt->rt_refcnt > 0)
241 panic("rtqkill route really not free");
242
243 err = rtrequest(RTM_DELETE,
244 (struct sockaddr *)rt_key(rt),
245 rt->rt_gateway, rt_mask(rt),
246 rt->rt_flags, 0);
247 if(err) {
248 log(LOG_WARNING, "in_rtqkill: error %d\n", err);
249 } else {
250 ap->killed++;
251 }
252 } else {
253 if(ap->updating
254 && (rt->rt_rmx.rmx_expire - time_second
255 > rtq_reallyold)) {
256 rt->rt_rmx.rmx_expire = time_second
257 + rtq_reallyold;
258 }
259 ap->nextstop = lmin(ap->nextstop,
260 rt->rt_rmx.rmx_expire);
261 }
262 }
263
264 return 0;
265}
266
267#define RTQ_TIMEOUT 60*10 /* run no less than once every ten minutes */
268static int rtq_timeout = RTQ_TIMEOUT;
269
270static void
271in_rtqtimo(void *rock)
272{
273 struct radix_node_head *rnh = rock;
274 struct rtqk_arg arg;
275 struct timeval atv;
276 static time_t last_adjusted_timeout = 0;
277 int s;
278
279 arg.found = arg.killed = 0;
280 arg.rnh = rnh;
281 arg.nextstop = time_second + rtq_timeout;
282 arg.draining = arg.updating = 0;
283 s = splnet();
284 rnh->rnh_walktree(rnh, in_rtqkill, &arg);
285 splx(s);
286
287 /*
288 * Attempt to be somewhat dynamic about this:
289 * If there are ``too many'' routes sitting around taking up space,
290 * then crank down the timeout, and see if we can't make some more
291 * go away. However, we make sure that we will never adjust more
292 * than once in rtq_timeout seconds, to keep from cranking down too
293 * hard.
294 */
295 if((arg.found - arg.killed > rtq_toomany)
296 && (time_second - last_adjusted_timeout >= rtq_timeout)
297 && rtq_reallyold > rtq_minreallyold) {
298 rtq_reallyold = 2*rtq_reallyold / 3;
299 if(rtq_reallyold < rtq_minreallyold) {
300 rtq_reallyold = rtq_minreallyold;
301 }
302
303 last_adjusted_timeout = time_second;
304#ifdef DIAGNOSTIC
305 log(LOG_DEBUG, "in_rtqtimo: adjusted rtq_reallyold to %d\n",
306 rtq_reallyold);
307#endif
308 arg.found = arg.killed = 0;
309 arg.updating = 1;
310 s = splnet();
311 rnh->rnh_walktree(rnh, in_rtqkill, &arg);
312 splx(s);
313 }
314
315 atv.tv_usec = 0;
316 atv.tv_sec = arg.nextstop - time_second;
317 timeout(in_rtqtimo, rock, tvtohz(&atv));
318}
319
320void
321in_rtqdrain(void)
322{
323 struct radix_node_head *rnh = rt_tables[AF_INET];
324 struct rtqk_arg arg;
325 int s;
326 arg.found = arg.killed = 0;
327 arg.rnh = rnh;
328 arg.nextstop = 0;
329 arg.draining = 1;
330 arg.updating = 0;
331 s = splnet();
332 rnh->rnh_walktree(rnh, in_rtqkill, &arg);
333 splx(s);
334}
335
336/*
337 * Initialize our routing tree.
338 */
339int
340in_inithead(void **head, int off)
341{
342 struct radix_node_head *rnh;
343
344 if(!rn_inithead(head, off))
345 return 0;
346
347 if(head != (void **)&rt_tables[AF_INET]) /* BOGUS! */
348 return 1; /* only do this for the real routing table */
349
350 rnh = *head;
351 rnh->rnh_addaddr = in_addroute;
352 rnh->rnh_matchaddr = in_matroute;
353 rnh->rnh_close = in_clsroute;
354 in_rtqtimo(rnh); /* kick off timeout first time */
355 return 1;
356}
357
358
359/*
360 * This zaps old routes when the interface goes down.
361 * Currently it doesn't delete static routes; there are
362 * arguments one could make for both behaviors. For the moment,
363 * we will adopt the Principle of Least Surprise and leave them
364 * alone (with the knowledge that this will not be enough for some
365 * people). The ones we really want to get rid of are things like ARP
366 * entries, since the user might down the interface, walk over to a completely
367 * different network, and plug back in.
368 */
369struct in_ifadown_arg {
370 struct radix_node_head *rnh;
371 struct ifaddr *ifa;
372};
373
374static int
375in_ifadownkill(struct radix_node *rn, void *xap)
376{
377 struct in_ifadown_arg *ap = xap;
378 struct rtentry *rt = (struct rtentry *)rn;
379 int err;
380
381 if (rt->rt_ifa == ap->ifa && !(rt->rt_flags & RTF_STATIC)) {
382 /*
383 * We need to disable the automatic prune that happens
384 * in this case in rtrequest() because it will blow
385 * away the pointers that rn_walktree() needs in order
386 * continue our descent. We will end up deleting all
387 * the routes that rtrequest() would have in any case,
388 * so that behavior is not needed there.
389 */
390 rt->rt_flags &= ~RTF_PRCLONING;
391 err = rtrequest(RTM_DELETE, (struct sockaddr *)rt_key(rt),
392 rt->rt_gateway, rt_mask(rt), rt->rt_flags, 0);
393 if (err) {
394 log(LOG_WARNING, "in_ifadownkill: error %d\n", err);
395 }
396 }
397 return 0;
398}
399
400int
401in_ifadown(struct ifaddr *ifa)
402{
403 struct in_ifadown_arg arg;
404 struct radix_node_head *rnh;
405
406 if (ifa->ifa_addr->sa_family != AF_INET)
407 return 1;
408
409 arg.rnh = rnh = rt_tables[AF_INET];
410 arg.ifa = ifa;
411 rnh->rnh_walktree(rnh, in_ifadownkill, &arg);
412 ifa->ifa_flags &= ~IFA_ROUTE;
413 return 0;
414}
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