[unix-history] / sbin / routed / input.c

/*
 * Copyright (c) 1983, 1988 Regents of the University of California.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#ifndef lint
static char sccsid[] = "@(#)input.c	5.22 (Berkeley) 6/1/90";
#endif /* not lint */

/*
 * Routing Table Management Daemon
 */
#include "defs.h"
#include <sys/syslog.h>

/*
 * Process a newly received packet.
 */
rip_input(from, rip, size)
	struct sockaddr *from;
	register struct rip *rip;
	int size;
{
	register struct rt_entry *rt;
	register struct netinfo *n;
	register struct interface *ifp;
	struct interface *if_ifwithdstaddr();
	int count, changes = 0;
	register struct afswitch *afp;
	static struct sockaddr badfrom, badfrom2;

	ifp = 0;
	TRACE_INPUT(ifp, from, (char *)rip, size);
	if (from->sa_family >= af_max ||
	    (afp = &afswitch[from->sa_family])->af_hash == (int (*)())0) {
		syslog(LOG_INFO,
	 "\"from\" address in unsupported address family (%d), cmd %d\n",
		    from->sa_family, rip->rip_cmd);
		return;
	}
	if (rip->rip_vers == 0) {
		syslog(LOG_ERR,
		    "RIP version 0 packet received from %s! (cmd %d)",
		    (*afswitch[from->sa_family].af_format)(from), rip->rip_cmd);
		return;
	}
	switch (rip->rip_cmd) {

	case RIPCMD_REQUEST:
		n = rip->rip_nets;
		count = size - ((char *)n - (char *)rip);
		if (count < sizeof (struct netinfo))
			return;
		for (; count > 0; n++) {
			if (count < sizeof (struct netinfo))
				break;
			count -= sizeof (struct netinfo);

#if BSD < 198810
			if (sizeof(n->rip_dst.sa_family) > 1)	/* XXX */
			    n->rip_dst.sa_family = ntohs(n->rip_dst.sa_family);
#else
#define osa(x) ((struct osockaddr *)(&(x)))
			    n->rip_dst.sa_family =
					ntohs(osa(n->rip_dst)->sa_family);
			    n->rip_dst.sa_len = sizeof(n->rip_dst);
#endif
			n->rip_metric = ntohl(n->rip_metric);
			/* 
			 * A single entry with sa_family == AF_UNSPEC and
			 * metric ``infinity'' means ``all routes''.
			 * We respond to routers only if we are acting
			 * as a supplier, or to anyone other than a router
			 * (eg, query).
			 */
			if (n->rip_dst.sa_family == AF_UNSPEC &&
			    n->rip_metric == HOPCNT_INFINITY && count == 0) {
			    	if (supplier || (*afp->af_portmatch)(from) == 0)
					supply(from, 0, 0, 0);
				return;
			}
			if (n->rip_dst.sa_family < af_max &&
			    afswitch[n->rip_dst.sa_family].af_hash)
				rt = rtlookup(&n->rip_dst);
			else
				rt = 0;
#define min(a, b) (a < b ? a : b)
			n->rip_metric = rt == 0 ? HOPCNT_INFINITY :
				min(rt->rt_metric + 1, HOPCNT_INFINITY);
#if BSD < 198810
			if (sizeof(n->rip_dst.sa_family) > 1)	/* XXX */
			    n->rip_dst.sa_family = htons(n->rip_dst.sa_family);
#else
			    osa(n->rip_dst)->sa_family =
						htons(n->rip_dst.sa_family);
#endif
			n->rip_metric = htonl(n->rip_metric);
		}
		rip->rip_cmd = RIPCMD_RESPONSE;
		bcopy((char *)rip, packet, size);
		(*afp->af_output)(s, 0, from, size);
		return;

	case RIPCMD_TRACEON:
	case RIPCMD_TRACEOFF:
		/* verify message came from a privileged port */
		if ((*afp->af_portcheck)(from) == 0)
			return;
		if ((ifp = if_iflookup(from)) == 0 || (ifp->int_flags &
		    (IFF_BROADCAST | IFF_POINTOPOINT | IFF_REMOTE)) == 0 ||
		    ifp->int_flags & IFF_PASSIVE) {
			syslog(LOG_ERR, "trace command from unknown router, %s",
			    (*afswitch[from->sa_family].af_format)(from));
			return;
		}
		((char *)rip)[size] = '\0';
		if (rip->rip_cmd == RIPCMD_TRACEON)
			traceon(rip->rip_tracefile);
		else
			traceoff();
		return;

	case RIPCMD_RESPONSE:
		/* verify message came from a router */
		if ((*afp->af_portmatch)(from) == 0)
			return;
		(*afp->af_canon)(from);
		/* are we talking to ourselves? */
		ifp = if_ifwithaddr(from);
		if (ifp) {
			if (ifp->int_flags & IFF_PASSIVE) {
				syslog(LOG_ERR,
				  "bogus input (from passive interface, %s)",
				  (*afswitch[from->sa_family].af_format)(from));
				return;
			}
			rt = rtfind(from);
			if (rt == 0 || ((rt->rt_state & RTS_INTERFACE) == 0) &&
			    rt->rt_metric >= ifp->int_metric) 
				addrouteforif(ifp);
			else
				rt->rt_timer = 0;
			return;
		}
		/*
		 * Update timer for interface on which the packet arrived.
		 * If from other end of a point-to-point link that isn't
		 * in the routing tables, (re-)add the route.
		 */
		if ((rt = rtfind(from)) &&
		    (rt->rt_state & (RTS_INTERFACE | RTS_REMOTE)))
			rt->rt_timer = 0;
		else if ((ifp = if_ifwithdstaddr(from)) &&
		    (rt == 0 || rt->rt_metric >= ifp->int_metric))
			addrouteforif(ifp);
		/*
		 * "Authenticate" router from which message originated.
		 * We accept routing packets from routers directly connected
		 * via broadcast or point-to-point networks,
		 * and from those listed in /etc/gateways.
		 */
		if ((ifp = if_iflookup(from)) == 0 || (ifp->int_flags &
		    (IFF_BROADCAST | IFF_POINTOPOINT | IFF_REMOTE)) == 0 ||
		    ifp->int_flags & IFF_PASSIVE) {
			if (bcmp((char *)from, (char *)&badfrom,
			    sizeof(badfrom)) != 0) {
				syslog(LOG_ERR,
				  "packet from unknown router, %s",
				  (*afswitch[from->sa_family].af_format)(from));
				badfrom = *from;
			}
			return;
		}
		size -= 4 * sizeof (char);
		n = rip->rip_nets;
		for (; size > 0; size -= sizeof (struct netinfo), n++) {
			if (size < sizeof (struct netinfo))
				break;
#if BSD < 198810
			if (sizeof(n->rip_dst.sa_family) > 1)	/* XXX */
				n->rip_dst.sa_family =
					ntohs(n->rip_dst.sa_family);
#else
			    n->rip_dst.sa_family =
					ntohs(osa(n->rip_dst)->sa_family);
			    n->rip_dst.sa_len = sizeof(n->rip_dst);
#endif
			n->rip_metric = ntohl(n->rip_metric);
			if (n->rip_dst.sa_family >= af_max ||
			    (afp = &afswitch[n->rip_dst.sa_family])->af_hash ==
			    (int (*)())0) {
				syslog(LOG_INFO,
		"route in unsupported address family (%d), from %s (af %d)\n",
				   n->rip_dst.sa_family,
				   (*afswitch[from->sa_family].af_format)(from),
				   from->sa_family);
				continue;
			}
			if (((*afp->af_checkhost)(&n->rip_dst)) == 0) {
				syslog(LOG_DEBUG,
				    "bad host in route from %s (af %d)\n",
				   (*afswitch[from->sa_family].af_format)(from),
				   from->sa_family);
				continue;
			}
			if (n->rip_metric == 0 ||
			    (unsigned) n->rip_metric > HOPCNT_INFINITY) {
				if (bcmp((char *)from, (char *)&badfrom2,
				    sizeof(badfrom2)) != 0) {
					syslog(LOG_ERR,
					    "bad metric (%d) from %s\n",
					    n->rip_metric,
				  (*afswitch[from->sa_family].af_format)(from));
					badfrom2 = *from;
				}
				continue;
			}
			/*
			 * Adjust metric according to incoming interface.
			 */
			if ((unsigned) n->rip_metric < HOPCNT_INFINITY)
				n->rip_metric += ifp->int_metric;
			if ((unsigned) n->rip_metric > HOPCNT_INFINITY)
				n->rip_metric = HOPCNT_INFINITY;
			rt = rtlookup(&n->rip_dst);
			if (rt == 0 ||
			    (rt->rt_state & (RTS_INTERNAL|RTS_INTERFACE)) ==
			    (RTS_INTERNAL|RTS_INTERFACE)) {
				/*
				 * If we're hearing a logical network route
				 * back from a peer to which we sent it,
				 * ignore it.
				 */
				if (rt && rt->rt_state & RTS_SUBNET &&
				    (*afp->af_sendroute)(rt, from))
					continue;
				if ((unsigned)n->rip_metric < HOPCNT_INFINITY) {
				    /*
				     * Look for an equivalent route that
				     * includes this one before adding
				     * this route.
				     */
				    rt = rtfind(&n->rip_dst);
				    if (rt && equal(from, &rt->rt_router))
					    continue;
				    rtadd(&n->rip_dst, from, n->rip_metric, 0);
				    changes++;
				}
				continue;
			}

			/*
			 * Update if from gateway and different,
			 * shorter, or equivalent but old route
			 * is getting stale.
			 */
			if (equal(from, &rt->rt_router)) {
				if (n->rip_metric != rt->rt_metric) {
					rtchange(rt, from, n->rip_metric);
					changes++;
					rt->rt_timer = 0;
					if (rt->rt_metric >= HOPCNT_INFINITY)
						rt->rt_timer =
						    GARBAGE_TIME - EXPIRE_TIME;
				} else if (rt->rt_metric < HOPCNT_INFINITY)
					rt->rt_timer = 0;
			} else if ((unsigned) n->rip_metric < rt->rt_metric ||
			    (rt->rt_metric == n->rip_metric &&
			    rt->rt_timer > (EXPIRE_TIME/2) &&
			    (unsigned) n->rip_metric < HOPCNT_INFINITY)) {
				rtchange(rt, from, n->rip_metric);
				changes++;
				rt->rt_timer = 0;
			}
		}
		break;
	}

	/*
	 * If changes have occurred, and if we have not sent a broadcast
	 * recently, send a dynamic update.  This update is sent only
	 * on interfaces other than the one on which we received notice
	 * of the change.  If we are within MIN_WAITTIME of a full update,
	 * don't bother sending; if we just sent a dynamic update
	 * and set a timer (nextbcast), delay until that time.
	 * If we just sent a full update, delay the dynamic update.
	 * Set a timer for a randomized value to suppress additional
	 * dynamic updates until it expires; if we delayed sending
	 * the current changes, set needupdate.
	 */
	if (changes && supplier &&
	   now.tv_sec - lastfullupdate.tv_sec < SUPPLY_INTERVAL-MAX_WAITTIME) {
		u_long delay;
		extern long random();

		if (now.tv_sec - lastbcast.tv_sec >= MIN_WAITTIME &&
		    timercmp(&nextbcast, &now, <)) {
			if (traceactions)
				fprintf(ftrace, "send dynamic update\n");
			toall(supply, RTS_CHANGED, ifp);
			lastbcast = now;
			needupdate = 0;
			nextbcast.tv_sec = 0;
		} else {
			needupdate++;
			if (traceactions)
				fprintf(ftrace, "delay dynamic update\n");
		}
#define RANDOMDELAY()	(MIN_WAITTIME * 1000000 + \
		(u_long)random() % ((MAX_WAITTIME - MIN_WAITTIME) * 1000000))

		if (nextbcast.tv_sec == 0) {
			delay = RANDOMDELAY();
			if (traceactions)
				fprintf(ftrace,
				    "inhibit dynamic update for %d usec\n",
				    delay);
			nextbcast.tv_sec = delay / 1000000;
			nextbcast.tv_usec = delay % 1000000;
			timevaladd(&nextbcast, &now);
			/*
			 * If the next possibly dynamic update
			 * is within MIN_WAITTIME of the next full update,
			 * force the delay past the full update,
			 * or we might send a dynamic update just before
			 * the full update.
			 */
			if (nextbcast.tv_sec > lastfullupdate.tv_sec +
			    SUPPLY_INTERVAL - MIN_WAITTIME)
				nextbcast.tv_sec = lastfullupdate.tv_sec +
				    SUPPLY_INTERVAL + 1;
		}
	}
}
Commit	Line	Data
15637ed4 RG	1	/*
	2	* Copyright (c) 1983, 1988 Regents of the University of California.
	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. All advertising materials mentioning features or use of this software
	14	* must display the following acknowledgement:
	15	* This product includes software developed by the University of
	16	* California, Berkeley and its contributors.
	17	* 4. Neither the name of the University nor the names of its contributors
	18	* may be used to endorse or promote products derived from this software
	19	* without specific prior written permission.
	20	*
	21	* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	22	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	23	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	24	* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	25	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	26	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	27	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	28	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	29	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	30	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	31	* SUCH DAMAGE.
	32	*/
	33
	34	#ifndef lint
	35	static char sccsid[] = "@(#)input.c 5.22 (Berkeley) 6/1/90";
	36	#endif /* not lint */
	37
	38	/*
	39	* Routing Table Management Daemon
	40	*/
	41	#include "defs.h"
	42	#include <sys/syslog.h>
	43
	44	/*
	45	* Process a newly received packet.
	46	*/
	47	rip_input(from, rip, size)
	48	struct sockaddr *from;
	49	register struct rip *rip;
	50	int size;
	51	{
	52	register struct rt_entry *rt;
	53	register struct netinfo *n;
	54	register struct interface *ifp;
	55	struct interface *if_ifwithdstaddr();
	56	int count, changes = 0;
	57	register struct afswitch *afp;
	58	static struct sockaddr badfrom, badfrom2;
	59
	60	ifp = 0;
	61	TRACE_INPUT(ifp, from, (char *)rip, size);
	62	if (from->sa_family >= af_max \|\|
	63	(afp = &afswitch[from->sa_family])->af_hash == (int (*)())0) {
	64	syslog(LOG_INFO,
65	"\"from\" address in unsupported address family (%d), cmd %d\n",
66	from->sa_family, rip->rip_cmd);
67	return;
68	}
69	if (rip->rip_vers == 0) {
70	syslog(LOG_ERR,
71	"RIP version 0 packet received from %s! (cmd %d)",
72	(*afswitch[from->sa_family].af_format)(from), rip->rip_cmd);
73	return;
74	}
75	switch (rip->rip_cmd) {
76
77	case RIPCMD_REQUEST:
78	n = rip->rip_nets;
79	count = size - ((char )n - (char )rip);
80	if (count < sizeof (struct netinfo))
81	return;
82	for (; count > 0; n++) {
83	if (count < sizeof (struct netinfo))
84	break;
85	count -= sizeof (struct netinfo);
86
87	#if BSD < 198810
88	if (sizeof(n->rip_dst.sa_family) > 1) /* XXX */
89	n->rip_dst.sa_family = ntohs(n->rip_dst.sa_family);
90	#else
91	#define osa(x) ((struct osockaddr *)(&(x)))
92	n->rip_dst.sa_family =
93	ntohs(osa(n->rip_dst)->sa_family);
94	n->rip_dst.sa_len = sizeof(n->rip_dst);
95	#endif
96	n->rip_metric = ntohl(n->rip_metric);
97	/*
98	* A single entry with sa_family == AF_UNSPEC and
99	* metric ``infinity'' means ``all routes''.
100	* We respond to routers only if we are acting
101	* as a supplier, or to anyone other than a router
102	* (eg, query).
103	*/
104	if (n->rip_dst.sa_family == AF_UNSPEC &&
105	n->rip_metric == HOPCNT_INFINITY && count == 0) {
106	if (supplier \|\| (*afp->af_portmatch)(from) == 0)
107	supply(from, 0, 0, 0);
108	return;
109	}
110	if (n->rip_dst.sa_family < af_max &&
111	afswitch[n->rip_dst.sa_family].af_hash)
112	rt = rtlookup(&n->rip_dst);
113	else
114	rt = 0;
115	#define min(a, b) (a < b ? a : b)
116	n->rip_metric = rt == 0 ? HOPCNT_INFINITY :
117	min(rt->rt_metric + 1, HOPCNT_INFINITY);
118	#if BSD < 198810
119	if (sizeof(n->rip_dst.sa_family) > 1) /* XXX */
120	n->rip_dst.sa_family = htons(n->rip_dst.sa_family);
121	#else
122	osa(n->rip_dst)->sa_family =
123	htons(n->rip_dst.sa_family);
124	#endif
125	n->rip_metric = htonl(n->rip_metric);
126	}
127	rip->rip_cmd = RIPCMD_RESPONSE;
128	bcopy((char *)rip, packet, size);
129	(*afp->af_output)(s, 0, from, size);
130	return;
131
132	case RIPCMD_TRACEON:
133	case RIPCMD_TRACEOFF:
134	/* verify message came from a privileged port */
135	if ((*afp->af_portcheck)(from) == 0)
136	return;
137	if ((ifp = if_iflookup(from)) == 0 \|\| (ifp->int_flags &
138	(IFF_BROADCAST \| IFF_POINTOPOINT \| IFF_REMOTE)) == 0 \|\|
139	ifp->int_flags & IFF_PASSIVE) {
140	syslog(LOG_ERR, "trace command from unknown router, %s",
141	(*afswitch[from->sa_family].af_format)(from));
142	return;
143	}
144	((char *)rip)[size] = '\0';
145	if (rip->rip_cmd == RIPCMD_TRACEON)
146	traceon(rip->rip_tracefile);
147	else
148	traceoff();
149	return;
150
151	case RIPCMD_RESPONSE:
152	/* verify message came from a router */
153	if ((*afp->af_portmatch)(from) == 0)
154	return;
155	(*afp->af_canon)(from);
156	/* are we talking to ourselves? */
157	ifp = if_ifwithaddr(from);
158	if (ifp) {
159	if (ifp->int_flags & IFF_PASSIVE) {
160	syslog(LOG_ERR,
161	"bogus input (from passive interface, %s)",
162	(*afswitch[from->sa_family].af_format)(from));
163	return;
164	}
165	rt = rtfind(from);
166	if (rt == 0 \|\| ((rt->rt_state & RTS_INTERFACE) == 0) &&
167	rt->rt_metric >= ifp->int_metric)
168	addrouteforif(ifp);
169	else
170	rt->rt_timer = 0;
171	return;
172	}
173	/*
174	* Update timer for interface on which the packet arrived.
175	* If from other end of a point-to-point link that isn't
176	* in the routing tables, (re-)add the route.
177	*/
178	if ((rt = rtfind(from)) &&
179	(rt->rt_state & (RTS_INTERFACE \| RTS_REMOTE)))
180	rt->rt_timer = 0;
181	else if ((ifp = if_ifwithdstaddr(from)) &&
182	(rt == 0 \|\| rt->rt_metric >= ifp->int_metric))
183	addrouteforif(ifp);
184	/*
185	* "Authenticate" router from which message originated.
186	* We accept routing packets from routers directly connected
187	* via broadcast or point-to-point networks,
188	* and from those listed in /etc/gateways.
189	*/
190	if ((ifp = if_iflookup(from)) == 0 \|\| (ifp->int_flags &
191	(IFF_BROADCAST \| IFF_POINTOPOINT \| IFF_REMOTE)) == 0 \|\|
192	ifp->int_flags & IFF_PASSIVE) {
193	if (bcmp((char )from, (char )&badfrom,
194	sizeof(badfrom)) != 0) {
195	syslog(LOG_ERR,
196	"packet from unknown router, %s",
197	(*afswitch[from->sa_family].af_format)(from));
198	badfrom = *from;
199	}
200	return;
201	}
202	size -= 4 * sizeof (char);
203	n = rip->rip_nets;
204	for (; size > 0; size -= sizeof (struct netinfo), n++) {
205	if (size < sizeof (struct netinfo))
206	break;
207	#if BSD < 198810
208	if (sizeof(n->rip_dst.sa_family) > 1) /* XXX */
209	n->rip_dst.sa_family =
210	ntohs(n->rip_dst.sa_family);
211	#else
212	n->rip_dst.sa_family =
213	ntohs(osa(n->rip_dst)->sa_family);
214	n->rip_dst.sa_len = sizeof(n->rip_dst);
215	#endif
216	n->rip_metric = ntohl(n->rip_metric);
217	if (n->rip_dst.sa_family >= af_max \|\|
218	(afp = &afswitch[n->rip_dst.sa_family])->af_hash ==
219	(int (*)())0) {
220	syslog(LOG_INFO,
221	"route in unsupported address family (%d), from %s (af %d)\n",
222	n->rip_dst.sa_family,
223	(*afswitch[from->sa_family].af_format)(from),
224	from->sa_family);
225	continue;
226	}
227	if (((*afp->af_checkhost)(&n->rip_dst)) == 0) {
228	syslog(LOG_DEBUG,
229	"bad host in route from %s (af %d)\n",
230	(*afswitch[from->sa_family].af_format)(from),
231	from->sa_family);
232	continue;
233	}
234	if (n->rip_metric == 0 \|\|
235	(unsigned) n->rip_metric > HOPCNT_INFINITY) {
236	if (bcmp((char )from, (char )&badfrom2,
237	sizeof(badfrom2)) != 0) {
238	syslog(LOG_ERR,
239	"bad metric (%d) from %s\n",
240	n->rip_metric,
241	(*afswitch[from->sa_family].af_format)(from));
242	badfrom2 = *from;
243	}
244	continue;
245	}
246	/*
247	* Adjust metric according to incoming interface.
248	*/
249	if ((unsigned) n->rip_metric < HOPCNT_INFINITY)
250	n->rip_metric += ifp->int_metric;
251	if ((unsigned) n->rip_metric > HOPCNT_INFINITY)
252	n->rip_metric = HOPCNT_INFINITY;
253	rt = rtlookup(&n->rip_dst);
254	if (rt == 0 \|\|
255	(rt->rt_state & (RTS_INTERNAL\|RTS_INTERFACE)) ==
256	(RTS_INTERNAL\|RTS_INTERFACE)) {
257	/*
258	* If we're hearing a logical network route
259	* back from a peer to which we sent it,
260	* ignore it.
261	*/
262	if (rt && rt->rt_state & RTS_SUBNET &&
263	(*afp->af_sendroute)(rt, from))
264	continue;
265	if ((unsigned)n->rip_metric < HOPCNT_INFINITY) {
266	/*
267	* Look for an equivalent route that
268	* includes this one before adding
269	* this route.
270	*/
271	rt = rtfind(&n->rip_dst);
272	if (rt && equal(from, &rt->rt_router))
273	continue;
274	rtadd(&n->rip_dst, from, n->rip_metric, 0);
275	changes++;
276	}
277	continue;
278	}
279
280	/*
281	* Update if from gateway and different,
282	* shorter, or equivalent but old route
283	* is getting stale.
284	*/
285	if (equal(from, &rt->rt_router)) {
286	if (n->rip_metric != rt->rt_metric) {
287	rtchange(rt, from, n->rip_metric);
288	changes++;
289	rt->rt_timer = 0;
290	if (rt->rt_metric >= HOPCNT_INFINITY)
291	rt->rt_timer =
292	GARBAGE_TIME - EXPIRE_TIME;
293	} else if (rt->rt_metric < HOPCNT_INFINITY)
294	rt->rt_timer = 0;
295	} else if ((unsigned) n->rip_metric < rt->rt_metric \|\|
296	(rt->rt_metric == n->rip_metric &&
297	rt->rt_timer > (EXPIRE_TIME/2) &&
298	(unsigned) n->rip_metric < HOPCNT_INFINITY)) {
299	rtchange(rt, from, n->rip_metric);
300	changes++;
301	rt->rt_timer = 0;
302	}
303	}
304	break;
305	}
306
307	/*
308	* If changes have occurred, and if we have not sent a broadcast
309	* recently, send a dynamic update. This update is sent only
310	* on interfaces other than the one on which we received notice
311	* of the change. If we are within MIN_WAITTIME of a full update,
312	* don't bother sending; if we just sent a dynamic update
313	* and set a timer (nextbcast), delay until that time.
314	* If we just sent a full update, delay the dynamic update.
315	* Set a timer for a randomized value to suppress additional
316	* dynamic updates until it expires; if we delayed sending
317	* the current changes, set needupdate.
318	*/
319	if (changes && supplier &&
320	now.tv_sec - lastfullupdate.tv_sec < SUPPLY_INTERVAL-MAX_WAITTIME) {
321	u_long delay;
322	extern long random();
323
324	if (now.tv_sec - lastbcast.tv_sec >= MIN_WAITTIME &&
325	timercmp(&nextbcast, &now, <)) {
326	if (traceactions)
327	fprintf(ftrace, "send dynamic update\n");
328	toall(supply, RTS_CHANGED, ifp);
329	lastbcast = now;
330	needupdate = 0;
331	nextbcast.tv_sec = 0;
332	} else {
333	needupdate++;
334	if (traceactions)
335	fprintf(ftrace, "delay dynamic update\n");
336	}
337	#define RANDOMDELAY() (MIN_WAITTIME * 1000000 + \
338	(u_long)random() % ((MAX_WAITTIME - MIN_WAITTIME) * 1000000))
339
340	if (nextbcast.tv_sec == 0) {
341	delay = RANDOMDELAY();
342	if (traceactions)
343	fprintf(ftrace,
344	"inhibit dynamic update for %d usec\n",
345	delay);
346	nextbcast.tv_sec = delay / 1000000;
347	nextbcast.tv_usec = delay % 1000000;
348	timevaladd(&nextbcast, &now);
349	/*
350	* If the next possibly dynamic update
351	* is within MIN_WAITTIME of the next full update,
352	* force the delay past the full update,
353	* or we might send a dynamic update just before
354	* the full update.
355	*/
356	if (nextbcast.tv_sec > lastfullupdate.tv_sec +
357	SUPPLY_INTERVAL - MIN_WAITTIME)
358	nextbcast.tv_sec = lastfullupdate.tv_sec +
359	SUPPLY_INTERVAL + 1;
360	}
361	}
362	}