1/*
2 * Copyright (c) 1983, 1988, 1993
3 *	The Regents of the University of California.  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 * 4. Neither the name of the University 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 REGENTS 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 REGENTS 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 * $FreeBSD$
30 */
31
32#include "defs.h"
33#include "pathnames.h"
34#ifdef sgi
35#include "math.h"
36#endif
37#include <signal.h>
38#include <fcntl.h>
39#include <sys/file.h>
40
41__COPYRIGHT("@(#) Copyright (c) 1983, 1988, 1993 "
42	    "The Regents of the University of California."
43	    "  All rights reserved.");
44#ifdef __NetBSD__
45__RCSID("$NetBSD$");
46#include <util.h>
47#elif defined(__FreeBSD__)
48__RCSID("$FreeBSD$");
49#else
50__RCSID("$Revision: 2.31 $");
51#ident "$Revision: 2.31 $"
52#endif
53
54pid_t	mypid;
55
56naddr	myaddr;				/* system address */
57static char myname[MAXHOSTNAMELEN+1];
58
59static int verbose;
60
61int	supplier;			/* supply or broadcast updates */
62int	supplier_set;
63static int ipforwarding = 1;		/* kernel forwarding on */
64
65static int default_gateway;		/* 1=advertise default */
66static int background = 1;
67int	ridhosts;			/* 1=reduce host routes */
68int	mhome;				/* 1=want multi-homed host route */
69int	advertise_mhome;		/* 1=must continue advertising it */
70int	auth_ok = 1;			/* 1=ignore auth if we do not care */
71int	insecure;			/* Reply to special queries or not */
72
73struct timeval epoch;			/* when started */
74struct timeval clk;
75static struct timeval prev_clk;
76static int usec_fudge;
77struct timeval now;			/* current idea of time */
78time_t	now_stale;
79time_t	now_expire;
80time_t	now_garbage;
81
82static struct timeval next_bcast;	/* next general broadcast */
83struct timeval no_flash = {		/* inhibit flash update */
84	EPOCH+SUPPLY_INTERVAL, 0
85};
86
87static struct timeval flush_kern_timer;
88
89static fd_set fdbits;
90static int sock_max;
91int	rip_sock = -1;			/* RIP socket */
92const struct interface *rip_sock_mcast;	/* current multicast interface */
93int	rt_sock;			/* routing socket */
94int	rt_sock_seqno;
95
96
97static  int get_rip_sock(naddr, int);
98static void timevalsub(struct timeval *, struct timeval *, struct timeval *);
99static void sigalrm(int s UNUSED);
100static void sigterm(int sig);
101
102int
103main(int argc,
104     char *argv[])
105{
106	int n, mib[4], off;
107	size_t len;
108	char *p, *q;
109	const char *cp;
110	struct timeval wtime, t2;
111	time_t dt;
112	fd_set ibits;
113	naddr p_net, p_mask;
114	struct interface *ifp;
115	struct parm parm;
116	char *tracename = 0;
117
118
119	/* Some shells are badly broken and send SIGHUP to backgrounded
120	 * processes.
121	 */
122	signal(SIGHUP, SIG_IGN);
123
124	openlog("routed", LOG_PID, LOG_DAEMON);
125	ftrace = stdout;
126
127	gettimeofday(&clk, 0);
128	prev_clk = clk;
129	epoch = clk;
130	epoch.tv_sec -= EPOCH;
131	now.tv_sec = EPOCH;
132	now_stale = EPOCH - STALE_TIME;
133	now_expire = EPOCH - EXPIRE_TIME;
134	now_garbage = EPOCH - GARBAGE_TIME;
135	wtime.tv_sec = 0;
136
137	(void)gethostname(myname, sizeof(myname)-1);
138	(void)gethost(myname, &myaddr);
139
140	while ((n = getopt(argc, argv, "isqdghmAtvT:F:P:")) != -1) {
141		switch (n) {
142		case 'i':
143			insecure++;
144			break;
145		case 's':
146			supplier = 1;
147			supplier_set = 1;
148			break;
149
150		case 'q':
151			supplier = 0;
152			supplier_set = 1;
153			break;
154
155		case 'd':
156			background = 0;
157			break;
158
159		case 'g':
160			memset(&parm, 0, sizeof(parm));
161			parm.parm_d_metric = 1;
162			cp = check_parms(&parm);
163			if (cp != 0)
164				msglog("bad -g: %s", cp);
165			else
166				default_gateway = 1;
167			break;
168
169		case 'h':		/* suppress extra host routes */
170			ridhosts = 1;
171			break;
172
173		case 'm':		/* advertise host route */
174			mhome = 1;	/* on multi-homed hosts */
175			break;
176
177		case 'A':
178			/* Ignore authentication if we do not care.
179			 * Crazy as it is, that is what RFC 1723 requires.
180			 */
181			auth_ok = 0;
182			break;
183
184		case 't':
185			new_tracelevel++;
186			break;
187
188		case 'T':
189			tracename = optarg;
190			break;
191
192		case 'F':		/* minimal routes for SLIP */
193			n = FAKE_METRIC;
194			p = strchr(optarg,',');
195			if (p && *p != '\0') {
196				n = (int)strtoul(p+1, &q, 0);
197				if (*q == '\0'
198				    && n <= HOPCNT_INFINITY-1
199				    && n >= 1)
200					*p = '\0';
201			}
202			if (!getnet(optarg, &p_net, &p_mask)) {
203				msglog("bad network; \"-F %s\"",
204				       optarg);
205				break;
206			}
207			memset(&parm, 0, sizeof(parm));
208			parm.parm_net = p_net;
209			parm.parm_mask = p_mask;
210			parm.parm_d_metric = n;
211			cp = check_parms(&parm);
212			if (cp != 0)
213				msglog("bad -F: %s", cp);
214			break;
215
216		case 'P':
217			/* handle arbitrary parameters.
218			 */
219			q = strdup(optarg);
220			cp = parse_parms(q, 0);
221			if (cp != 0)
222				msglog("%s in \"-P %s\"", cp, optarg);
223			free(q);
224			break;
225
226		case 'v':
227			/* display version */
228			verbose++;
229			msglog("version 2.31");
230			break;
231
232		default:
233			goto usage;
234		}
235	}
236	argc -= optind;
237	argv += optind;
238
239	if (tracename == 0 && argc >= 1) {
240		tracename = *argv++;
241		argc--;
242	}
243	if (tracename != 0 && tracename[0] == '\0')
244		goto usage;
245	if (argc != 0) {
246usage:
247		logbad(0, "usage: routed [-sqdghmAtv] [-T tracefile]"
248		       " [-F net[,metric]] [-P parms]");
249	}
250	if (geteuid() != 0) {
251		if (verbose)
252			exit(0);
253		logbad(0, "requires UID 0");
254	}
255
256	mib[0] = CTL_NET;
257	mib[1] = PF_INET;
258	mib[2] = IPPROTO_IP;
259	mib[3] = IPCTL_FORWARDING;
260	len = sizeof(ipforwarding);
261	if (sysctl(mib, 4, &ipforwarding, &len, 0, 0) < 0)
262		LOGERR("sysctl(IPCTL_FORWARDING)");
263
264	if (!ipforwarding) {
265		if (supplier)
266			msglog("-s incompatible with ipforwarding=0");
267		if (default_gateway) {
268			msglog("-g incompatible with ipforwarding=0");
269			default_gateway = 0;
270		}
271		supplier = 0;
272		supplier_set = 1;
273	}
274	if (default_gateway) {
275		if (supplier_set && !supplier) {
276			msglog("-g and -q incompatible");
277		} else {
278			supplier = 1;
279			supplier_set = 1;
280		}
281	}
282
283
284	signal(SIGALRM, sigalrm);
285	if (!background)
286		signal(SIGHUP, sigterm);    /* SIGHUP fatal during debugging */
287	signal(SIGTERM, sigterm);
288	signal(SIGINT, sigterm);
289	signal(SIGUSR1, sigtrace_on);
290	signal(SIGUSR2, sigtrace_off);
291
292	/* get into the background */
293#ifdef sgi
294	if (0 > _daemonize(background ? 0 : (_DF_NOCHDIR|_DF_NOFORK),
295			   STDIN_FILENO, STDOUT_FILENO, STDERR_FILENO))
296		BADERR(0, "_daemonize()");
297#else
298	if (background && daemon(0, 1) < 0)
299		BADERR(0,"daemon()");
300#endif
301
302#if defined(__NetBSD__)
303	pidfile(0);
304#endif
305	mypid = getpid();
306#ifdef __FreeBSD__
307	srandomdev();
308#else
309	srandom((int)(clk.tv_sec ^ clk.tv_usec ^ mypid));
310#endif
311
312	/* prepare socket connected to the kernel.
313	 */
314	rt_sock = socket(AF_ROUTE, SOCK_RAW, 0);
315	if (rt_sock < 0)
316		BADERR(1,"rt_sock = socket()");
317	if (fcntl(rt_sock, F_SETFL, O_NONBLOCK) == -1)
318		logbad(1, "fcntl(rt_sock) O_NONBLOCK: %s", strerror(errno));
319	off = 0;
320	if (setsockopt(rt_sock, SOL_SOCKET,SO_USELOOPBACK,
321		       &off,sizeof(off)) < 0)
322		LOGERR("setsockopt(SO_USELOOPBACK,0)");
323
324	fix_select();
325
326
327	if (tracename != 0) {
328		strncpy(inittracename, tracename, sizeof(inittracename)-1);
329		set_tracefile(inittracename, "%s", -1);
330	} else {
331		tracelevel_msg("%s", -1);   /* turn on tracing to stdio */
332	}
333
334	bufinit();
335
336	/* initialize radix tree */
337	rtinit();
338
339	/* Pick a random part of the second for our output to minimize
340	 * collisions.
341	 *
342	 * Start broadcasting after hearing from other routers, and
343	 * at a random time so a bunch of systems do not get synchronized
344	 * after a power failure.
345	 */
346	intvl_random(&next_bcast, EPOCH+MIN_WAITTIME, EPOCH+SUPPLY_INTERVAL);
347	age_timer.tv_usec = next_bcast.tv_usec;
348	age_timer.tv_sec = EPOCH+MIN_WAITTIME;
349	rdisc_timer = next_bcast;
350	ifinit_timer.tv_usec = next_bcast.tv_usec;
351
352	/* Collect an initial view of the world by checking the interface
353	 * configuration and the kludge file.
354	 */
355	gwkludge();
356	ifinit();
357
358	/* Ask for routes */
359	rip_query();
360	rdisc_sol();
361
362	/* Now turn off stdio if not tracing */
363	if (new_tracelevel == 0)
364		trace_close(background);
365
366	/* Loop forever, listening and broadcasting.
367	 */
368	for (;;) {
369		prev_clk = clk;
370		gettimeofday(&clk, 0);
371		if (prev_clk.tv_sec == clk.tv_sec
372		    && prev_clk.tv_usec == clk.tv_usec+usec_fudge) {
373			/* Much of `routed` depends on time always advancing.
374			 * On systems that do not guarantee that gettimeofday()
375			 * produces unique timestamps even if called within
376			 * a single tick, use trickery like that in classic
377			 * BSD kernels.
378			 */
379			clk.tv_usec += ++usec_fudge;
380
381		} else {
382			usec_fudge = 0;
383
384			timevalsub(&t2, &clk, &prev_clk);
385			if (t2.tv_sec < 0
386			    || t2.tv_sec > wtime.tv_sec + 5) {
387				/* Deal with time changes before other
388				 * housekeeping to keep everything straight.
389				 */
390				dt = t2.tv_sec;
391				if (dt > 0)
392					dt -= wtime.tv_sec;
393				trace_act("time changed by %d sec", (int)dt);
394				epoch.tv_sec += dt;
395			}
396		}
397		timevalsub(&now, &clk, &epoch);
398		now_stale = now.tv_sec - STALE_TIME;
399		now_expire = now.tv_sec - EXPIRE_TIME;
400		now_garbage = now.tv_sec - GARBAGE_TIME;
401
402		/* deal with signals that should affect tracing */
403		set_tracelevel();
404
405		if (stopint != 0) {
406			rip_bcast(0);
407			rdisc_adv();
408			trace_off("exiting with signal %d", stopint);
409			exit(stopint | 128);
410		}
411
412		/* look for new or dead interfaces */
413		timevalsub(&wtime, &ifinit_timer, &now);
414		if (wtime.tv_sec <= 0) {
415			wtime.tv_sec = 0;
416			ifinit();
417			rip_query();
418			continue;
419		}
420
421		/* Check the kernel table occasionally for mysteriously
422		 * evaporated routes
423		 */
424		timevalsub(&t2, &flush_kern_timer, &now);
425		if (t2.tv_sec <= 0) {
426			flush_kern();
427			flush_kern_timer.tv_sec = (now.tv_sec
428						   + CHECK_QUIET_INTERVAL);
429			continue;
430		}
431		if (timercmp(&t2, &wtime, <))
432			wtime = t2;
433
434		/* If it is time, then broadcast our routes.
435		 */
436		if (supplier || advertise_mhome) {
437			timevalsub(&t2, &next_bcast, &now);
438			if (t2.tv_sec <= 0) {
439				/* Synchronize the aging and broadcast
440				 * timers to minimize awakenings
441				 */
442				age(0);
443
444				rip_bcast(0);
445
446				/* It is desirable to send routing updates
447				 * regularly.  So schedule the next update
448				 * 30 seconds after the previous one was
449				 * scheduled, instead of 30 seconds after
450				 * the previous update was finished.
451				 * Even if we just started after discovering
452				 * a 2nd interface or were otherwise delayed,
453				 * pick a 30-second anniversary of the
454				 * original broadcast time.
455				 */
456				n = 1 + (0-t2.tv_sec)/SUPPLY_INTERVAL;
457				next_bcast.tv_sec += n*SUPPLY_INTERVAL;
458
459				continue;
460			}
461
462			if (timercmp(&t2, &wtime, <))
463				wtime = t2;
464		}
465
466		/* If we need a flash update, either do it now or
467		 * set the delay to end when it is time.
468		 *
469		 * If we are within MIN_WAITTIME seconds of a full update,
470		 * do not bother.
471		 */
472		if (need_flash
473		    && supplier
474		    && no_flash.tv_sec+MIN_WAITTIME < next_bcast.tv_sec) {
475			/* accurate to the millisecond */
476			if (!timercmp(&no_flash, &now, >))
477				rip_bcast(1);
478			timevalsub(&t2, &no_flash, &now);
479			if (timercmp(&t2, &wtime, <))
480				wtime = t2;
481		}
482
483		/* trigger the main aging timer.
484		 */
485		timevalsub(&t2, &age_timer, &now);
486		if (t2.tv_sec <= 0) {
487			age(0);
488			continue;
489		}
490		if (timercmp(&t2, &wtime, <))
491			wtime = t2;
492
493		/* update the kernel routing table
494		 */
495		timevalsub(&t2, &need_kern, &now);
496		if (t2.tv_sec <= 0) {
497			age(0);
498			continue;
499		}
500		if (timercmp(&t2, &wtime, <))
501			wtime = t2;
502
503		/* take care of router discovery,
504		 * but do it in the correct the millisecond
505		 */
506		if (!timercmp(&rdisc_timer, &now, >)) {
507			rdisc_age(0);
508			continue;
509		}
510		timevalsub(&t2, &rdisc_timer, &now);
511		if (timercmp(&t2, &wtime, <))
512			wtime = t2;
513
514
515		/* wait for input or a timer to expire.
516		 */
517		trace_flush();
518		ibits = fdbits;
519		n = select(sock_max, &ibits, 0, 0, &wtime);
520		if (n <= 0) {
521			if (n < 0 && errno != EINTR && errno != EAGAIN)
522				BADERR(1,"select");
523			continue;
524		}
525
526		if (FD_ISSET(rt_sock, &ibits)) {
527			read_rt();
528			n--;
529		}
530		if (rdisc_sock >= 0 && FD_ISSET(rdisc_sock, &ibits)) {
531			read_d();
532			n--;
533		}
534		if (rip_sock >= 0 && FD_ISSET(rip_sock, &ibits)) {
535			read_rip(rip_sock, 0);
536			n--;
537		}
538
539		LIST_FOREACH(ifp, &ifnet, int_list) {
540			if (n <= 0)
541				break;
542			if (ifp->int_rip_sock >= 0
543			    && FD_ISSET(ifp->int_rip_sock, &ibits)) {
544				read_rip(ifp->int_rip_sock, ifp);
545				n--;
546			}
547		}
548	}
549}
550
551
552/* ARGSUSED */
553static void
554sigalrm(int s UNUSED)
555{
556	/* Historically, SIGALRM would cause the daemon to check for
557	 * new and broken interfaces.
558	 */
559	ifinit_timer.tv_sec = now.tv_sec;
560	trace_act("SIGALRM");
561}
562
563
564/* watch for fatal signals */
565static void
566sigterm(int sig)
567{
568	stopint = sig;
569	(void)signal(sig, SIG_DFL);	/* catch it only once */
570}
571
572
573void
574fix_select(void)
575{
576	struct interface *ifp;
577
578
579	FD_ZERO(&fdbits);
580	sock_max = 0;
581
582	FD_SET(rt_sock, &fdbits);
583	if (sock_max <= rt_sock)
584		sock_max = rt_sock+1;
585	if (rip_sock >= 0) {
586		FD_SET(rip_sock, &fdbits);
587		if (sock_max <= rip_sock)
588			sock_max = rip_sock+1;
589	}
590	LIST_FOREACH(ifp, &ifnet, int_list) {
591		if (ifp->int_rip_sock >= 0) {
592			FD_SET(ifp->int_rip_sock, &fdbits);
593			if (sock_max <= ifp->int_rip_sock)
594				sock_max = ifp->int_rip_sock+1;
595		}
596	}
597	if (rdisc_sock >= 0) {
598		FD_SET(rdisc_sock, &fdbits);
599		if (sock_max <= rdisc_sock)
600			sock_max = rdisc_sock+1;
601	}
602}
603
604
605void
606fix_sock(int sock,
607	 const char *name)
608{
609	int on;
610#define MIN_SOCKBUF (4*1024)
611	static int rbuf;
612
613	if (fcntl(sock, F_SETFL, O_NONBLOCK) == -1)
614		logbad(1, "fcntl(%s) O_NONBLOCK: %s",
615		       name, strerror(errno));
616	on = 1;
617	if (setsockopt(sock, SOL_SOCKET,SO_BROADCAST, &on,sizeof(on)) < 0)
618		msglog("setsockopt(%s,SO_BROADCAST): %s",
619		       name, strerror(errno));
620#ifdef USE_PASSIFNAME
621	on = 1;
622	if (setsockopt(sock, SOL_SOCKET, SO_PASSIFNAME, &on,sizeof(on)) < 0)
623		msglog("setsockopt(%s,SO_PASSIFNAME): %s",
624		       name, strerror(errno));
625#endif
626
627	if (rbuf >= MIN_SOCKBUF) {
628		if (setsockopt(sock, SOL_SOCKET, SO_RCVBUF,
629			       &rbuf, sizeof(rbuf)) < 0)
630			msglog("setsockopt(%s,SO_RCVBUF=%d): %s",
631			       name, rbuf, strerror(errno));
632	} else {
633		for (rbuf = 60*1024; ; rbuf -= 4096) {
634			if (setsockopt(sock, SOL_SOCKET, SO_RCVBUF,
635				       &rbuf, sizeof(rbuf)) == 0) {
636				trace_act("RCVBUF=%d", rbuf);
637				break;
638			}
639			if (rbuf < MIN_SOCKBUF) {
640				msglog("setsockopt(%s,SO_RCVBUF = %d): %s",
641				       name, rbuf, strerror(errno));
642				break;
643			}
644		}
645	}
646}
647
648
649/* get a rip socket
650 */
651static int				/* <0 or file descriptor */
652get_rip_sock(naddr addr,
653	     int serious)		/* 1=failure to bind is serious */
654{
655	struct sockaddr_in rsin;
656	unsigned char ttl;
657	int s;
658
659
660	if ((s = socket(AF_INET, SOCK_DGRAM, 0)) < 0)
661		BADERR(1,"rip_sock = socket()");
662
663	memset(&rsin, 0, sizeof(rsin));
664#ifdef _HAVE_SIN_LEN
665	rsin.sin_len = sizeof(rsin);
666#endif
667	rsin.sin_family = AF_INET;
668	rsin.sin_port = htons(RIP_PORT);
669	rsin.sin_addr.s_addr = addr;
670	if (bind(s, (struct sockaddr *)&rsin, sizeof(rsin)) < 0) {
671		if (serious)
672			BADERR(errno != EADDRINUSE, "bind(rip_sock)");
673		return -1;
674	}
675	fix_sock(s,"rip_sock");
676
677	ttl = 1;
678	if (setsockopt(s, IPPROTO_IP, IP_MULTICAST_TTL,
679		       &ttl, sizeof(ttl)) < 0)
680		DBGERR(1,"rip_sock setsockopt(IP_MULTICAST_TTL)");
681
682	return s;
683}
684
685
686/* turn off main RIP socket */
687void
688rip_off(void)
689{
690	struct interface *ifp;
691	naddr addr;
692
693
694	if (rip_sock >= 0 && !mhome) {
695		trace_act("turn off RIP");
696
697		(void)close(rip_sock);
698		rip_sock = -1;
699
700		/* get non-broadcast sockets to listen to queries.
701		 */
702		LIST_FOREACH(ifp, &ifnet, int_list) {
703			if (ifp->int_state & IS_REMOTE)
704				continue;
705			if (ifp->int_rip_sock < 0) {
706				addr = ((ifp->int_if_flags & IFF_POINTOPOINT)
707					? ifp->int_dstaddr
708					: ifp->int_addr);
709				ifp->int_rip_sock = get_rip_sock(addr, 0);
710			}
711		}
712
713		fix_select();
714
715		age(0);
716	}
717}
718
719
720/* turn on RIP multicast input via an interface
721 */
722static void
723rip_mcast_on(struct interface *ifp)
724{
725	struct group_req gr;
726	struct sockaddr_in *sin;
727
728	if (!IS_RIP_IN_OFF(ifp->int_state)
729	    && (ifp->int_if_flags & IFF_MULTICAST)
730	    && !(ifp->int_state & IS_ALIAS)) {
731		memset(&gr, 0, sizeof(gr));
732		gr.gr_interface = ifp->int_index;
733		sin = (struct sockaddr_in *)&gr.gr_group;
734		sin->sin_family = AF_INET;
735#ifdef _HAVE_SIN_LEN
736		sin->sin_len = sizeof(struct sockaddr_in);
737#endif
738		sin->sin_addr.s_addr = htonl(INADDR_RIP_GROUP);
739		if (setsockopt(rip_sock, IPPROTO_IP, MCAST_JOIN_GROUP,
740			       &gr, sizeof(gr)) < 0)
741			LOGERR("setsockopt(MCAST_JOIN_GROUP RIP)");
742	}
743}
744
745
746/* Prepare socket used for RIP.
747 */
748void
749rip_on(struct interface *ifp)
750{
751	/* If the main RIP socket is already alive, only start receiving
752	 * multicasts for this interface.
753	 */
754	if (rip_sock >= 0) {
755		if (ifp != 0)
756			rip_mcast_on(ifp);
757		return;
758	}
759
760	/* If the main RIP socket is off and it makes sense to turn it on,
761	 * then turn it on for all of the interfaces.
762	 * It makes sense if either router discovery is off, or if
763	 * router discover is on and at most one interface is doing RIP.
764	 */
765	if (rip_interfaces > 0 && (!rdisc_ok || rip_interfaces > 1)) {
766		trace_act("turn on RIP");
767
768		/* Close all of the query sockets so that we can open
769		 * the main socket.  SO_REUSEPORT is not a solution,
770		 * since that would let two daemons bind to the broadcast
771		 * socket.
772		 */
773		LIST_FOREACH(ifp, &ifnet, int_list) {
774			if (ifp->int_rip_sock >= 0) {
775				(void)close(ifp->int_rip_sock);
776				ifp->int_rip_sock = -1;
777			}
778		}
779
780		rip_sock = get_rip_sock(INADDR_ANY, 1);
781		rip_sock_mcast = 0;
782
783		/* Do not advertise anything until we have heard something
784		 */
785		if (next_bcast.tv_sec < now.tv_sec+MIN_WAITTIME)
786			next_bcast.tv_sec = now.tv_sec+MIN_WAITTIME;
787
788		LIST_FOREACH(ifp, &ifnet, int_list) {
789			ifp->int_query_time = NEVER;
790			rip_mcast_on(ifp);
791		}
792		ifinit_timer.tv_sec = now.tv_sec;
793
794	} else if (ifp != 0
795		   && !(ifp->int_state & IS_REMOTE)
796		   && ifp->int_rip_sock < 0) {
797		/* RIP is off, so ensure there are sockets on which
798		 * to listen for queries.
799		 */
800		ifp->int_rip_sock = get_rip_sock(ifp->int_addr, 0);
801	}
802
803	fix_select();
804}
805
806
807/* die if malloc(3) fails
808 */
809void *
810rtmalloc(size_t size,
811	 const char *msg)
812{
813	void *p = malloc(size);
814	if (p == 0)
815		logbad(1,"malloc(%lu) failed in %s", (u_long)size, msg);
816	return p;
817}
818
819
820/* get a random instant in an interval
821 */
822void
823intvl_random(struct timeval *tp,	/* put value here */
824	     u_long lo,			/* value is after this second */
825	     u_long hi)			/* and before this */
826{
827	tp->tv_sec = (time_t)(hi == lo
828			      ? lo
829			      : (lo + random() % ((hi - lo))));
830	tp->tv_usec = random() % 1000000;
831}
832
833
834void
835timevaladd(struct timeval *t1,
836	   struct timeval *t2)
837{
838
839	t1->tv_sec += t2->tv_sec;
840	if ((t1->tv_usec += t2->tv_usec) >= 1000000) {
841		t1->tv_sec++;
842		t1->tv_usec -= 1000000;
843	}
844}
845
846
847/* t1 = t2 - t3
848 */
849static void
850timevalsub(struct timeval *t1,
851	   struct timeval *t2,
852	   struct timeval *t3)
853{
854	t1->tv_sec = t2->tv_sec - t3->tv_sec;
855	if ((t1->tv_usec = t2->tv_usec - t3->tv_usec) < 0) {
856		t1->tv_sec--;
857		t1->tv_usec += 1000000;
858	}
859}
860
861
862/* put a message into the system log
863 */
864void
865msglog(const char *p, ...)
866{
867	va_list args;
868
869	trace_flush();
870
871	va_start(args, p);
872	vsyslog(LOG_ERR, p, args);
873	va_end(args);
874	if (ftrace != 0) {
875		if (ftrace == stdout)
876			(void)fputs("routed: ", ftrace);
877		va_start(args, p);
878		(void)vfprintf(ftrace, p, args);
879		va_end(args);
880		(void)fputc('\n', ftrace);
881	}
882}
883
884
885/* Put a message about a bad system into the system log if
886 * we have not complained about it recently.
887 *
888 * It is desirable to complain about all bad systems, but not too often.
889 * In the worst case, it is not practical to keep track of all bad systems.
890 * For example, there can be many systems with the wrong password.
891 */
892void
893msglim(struct msg_limit *lim, naddr addr, const char *p, ...)
894{
895	va_list args;
896	int i;
897	struct msg_sub *ms1, *ms;
898	const char *p1;
899
900	/* look for the oldest slot in the table
901	 * or the slot for the bad router.
902	 */
903	ms = ms1 = lim->subs;
904	for (i = MSG_SUBJECT_N; ; i--, ms1++) {
905		if (i == 0) {
906			/* Reuse a slot at most once every 10 minutes.
907			 */
908			if (lim->reuse > now.tv_sec) {
909				ms = 0;
910			} else {
911				ms = ms1;
912				lim->reuse = now.tv_sec + 10*60;
913			}
914			break;
915		}
916		if (ms->addr == addr) {
917			/* Repeat a complaint about a given system at
918			 * most once an hour.
919			 */
920			if (ms->until > now.tv_sec)
921				ms = 0;
922			break;
923		}
924		if (ms->until < ms1->until)
925			ms = ms1;
926	}
927	if (ms != 0) {
928		ms->addr = addr;
929		ms->until = now.tv_sec + 60*60;	/* 60 minutes */
930
931		trace_flush();
932		for (p1 = p; *p1 == ' '; p1++)
933			continue;
934		va_start(args, p);
935		vsyslog(LOG_ERR, p1, args);
936		va_end(args);
937	}
938
939	/* always display the message if tracing */
940	if (ftrace != 0) {
941		va_start(args, p);
942		(void)vfprintf(ftrace, p, args);
943		va_end(args);
944		(void)fputc('\n', ftrace);
945	}
946}
947
948
949void
950logbad(int dump, const char *p, ...)
951{
952	va_list args;
953
954	trace_flush();
955
956	va_start(args, p);
957	vsyslog(LOG_ERR, p, args);
958	va_end(args);
959	(void)fputs("routed: ", stderr);
960	va_start(args, p);
961	(void)vfprintf(stderr, p, args);
962	va_end(args);
963	(void)fputs("; giving up\n",stderr);
964	(void)fflush(stderr);
965
966	if (dump)
967		abort();
968	exit(1);
969}
970