1/*	$NetBSD: main.c,v 1.40 2008/07/20 01:20:23 lukem Exp $	*/
2
3/*
4 * Copyright (c) 1983, 1988, 1993
5 *	The Regents of the University of California.  All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 * 3. All advertising materials mentioning features or use of this software
16 *    must display the following acknowledgment:
17 *	This product includes software developed by the University of
18 *	California, Berkeley and its contributors.
19 * 4. Neither the name of the University nor the names of its contributors
20 *    may be used to endorse or promote products derived from this software
21 *    without specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 */
35
36#include "defs.h"
37#include "pathnames.h"
38#ifdef sgi
39#include "math.h"
40#endif
41#if defined(__NetBSD__)
42#include <util.h>
43#endif
44#include <signal.h>
45#include <fcntl.h>
46#include <sys/file.h>
47
48__COPYRIGHT("@(#) Copyright (c) 1983, 1988, 1993\
49 The Regents of the University of California.  All rights reserved.");
50#ifdef __NetBSD__
51__RCSID("$NetBSD: main.c,v 1.40 2008/07/20 01:20:23 lukem Exp $");
52#elif defined(__FreeBSD__)
53__RCSID("$FreeBSD$");
54#else
55__RCSID("Revision: 2.27 ");
56#ident "Revision: 2.27 "
57#endif
58
59pid_t	mypid;
60
61naddr	myaddr;				/* system address */
62char	myname[MAXHOSTNAMELEN+1];
63
64int	verbose;
65
66int	supplier;			/* supply or broadcast updates */
67int	supplier_set;
68int	ipforwarding = 1;		/* kernel forwarding on */
69
70int	default_gateway;		/* 1=advertise default */
71int	background = 1;
72int	ridhosts;			/* 1=reduce host routes */
73int	mhome;				/* 1=want multi-homed host route */
74int	advertise_mhome;		/* 1=must continue advertising it */
75int	auth_ok = 1;			/* 1=ignore auth if we do not care */
76
77struct timeval epoch;			/* when started */
78struct timeval clk, prev_clk;
79static int usec_fudge;
80struct timeval now;			/* current idea of time */
81time_t	now_stale;
82time_t	now_expire;
83time_t	now_garbage;
84
85struct timeval next_bcast;		/* next general broadcast */
86struct timeval no_flash = {		/* inhibit flash update */
87	EPOCH+SUPPLY_INTERVAL, 0
88};
89
90struct timeval flush_kern_timer;
91
92fd_set	*fdbitsp;
93int	sock_max;
94int	rip_sock = -1;			/* RIP socket */
95struct interface *rip_sock_mcast;	/* current multicast interface */
96int	rt_sock;			/* routing socket */
97int	rt_sock_seqno;
98
99
100static  int get_rip_sock(naddr, int);
101static void timevalsub(struct timeval *, struct timeval *, struct timeval *);
102
103int
104main(int argc,
105     char *argv[])
106{
107	int n, mib[4], off;
108	size_t len;
109	char *p, *q;
110	const char *cp;
111	struct timeval wtime, t2;
112	time_t dt;
113	fd_set *ibitsp = NULL;
114	naddr p_net, p_mask;
115	struct interface *ifp;
116	struct parm parm;
117	char *tracename = 0;
118
119
120	/* Some shells are badly broken and send SIGHUP to backgrounded
121	 * processes.
122	 */
123	signal(SIGHUP, SIG_IGN);
124
125	openlog("routed", LOG_PID, LOG_DAEMON);
126	ftrace = stdout;
127
128	gettimeofday(&clk, 0);
129	prev_clk = clk;
130	epoch = clk;
131	epoch.tv_sec -= EPOCH;
132	now.tv_sec = EPOCH;
133	now_stale = EPOCH - STALE_TIME;
134	now_expire = EPOCH - EXPIRE_TIME;
135	now_garbage = EPOCH - GARBAGE_TIME;
136	wtime.tv_sec = 0;
137
138	(void)gethostname(myname, sizeof(myname) - 1);
139	(void)gethost(myname, &myaddr);
140
141	while ((n = getopt(argc, argv, "sqdghmAtvT:F:P:")) != -1) {
142		switch (n) {
143		case 's':
144			supplier = 1;
145			supplier_set = 1;
146			break;
147
148		case 'q':
149			supplier = 0;
150			supplier_set = 1;
151			break;
152
153		case 'd':
154			background = 0;
155			break;
156
157		case 'g':
158			memset(&parm, 0, sizeof(parm));
159			parm.parm_d_metric = 1;
160			cp = check_parms(&parm);
161			if (cp != 0)
162				msglog("bad -g: %s", cp);
163			else
164				default_gateway = 1;
165			break;
166
167		case 'h':		/* suppress extra host routes */
168			ridhosts = 1;
169			break;
170
171		case 'm':		/* advertise host route */
172			mhome = 1;	/* on multi-homed hosts */
173			break;
174
175		case 'A':
176			/* Ignore authentication if we do not care.
177			 * Crazy as it is, that is what RFC 1723 requires.
178			 */
179			auth_ok = 0;
180			break;
181
182		case 't':
183			new_tracelevel++;
184			break;
185
186		case 'T':
187			tracename = optarg;
188			break;
189
190		case 'F':		/* minimal routes for SLIP */
191			n = FAKE_METRIC;
192			p = strchr(optarg,',');
193			if (p && *p != '\0') {
194				n = (int)strtoul(p+1, &q, 0);
195				if (*q == '\0'
196				    && n <= HOPCNT_INFINITY-1
197				    && n >= 1)
198					*p = '\0';
199			}
200			if (!getnet(optarg, &p_net, &p_mask)) {
201				msglog("bad network; \"-F %s\"",
202				       optarg);
203				break;
204			}
205			memset(&parm, 0, sizeof(parm));
206			parm.parm_net = p_net;
207			parm.parm_mask = p_mask;
208			parm.parm_d_metric = n;
209			cp = check_parms(&parm);
210			if (cp != 0)
211				msglog("bad -F: %s", cp);
212			break;
213
214		case 'P':
215			/* handle arbitrary parameters.
216			 */
217			q = strdup(optarg);
218			cp = parse_parms(q, 0);
219			if (cp != 0)
220				msglog("%s in \"-P %s\"", cp, optarg);
221			free(q);
222			break;
223
224		case 'v':
225			/* display version */
226			verbose++;
227			msglog("version 2.32");
228			break;
229
230		default:
231			goto usage;
232		}
233	}
234	argc -= optind;
235	argv += optind;
236
237	if (tracename == 0 && argc >= 1) {
238		tracename = *argv++;
239		argc--;
240	}
241	if (tracename != 0 && tracename[0] == '\0')
242		goto usage;
243	if (argc != 0) {
244usage:
245		logbad(0, "usage: routed [-sqdghmAtv] [-T tracefile]"
246		       " [-F net[/mask[,metric]]] [-P parms]");
247	}
248	if (geteuid() != 0) {
249		if (verbose)
250			exit(0);
251		logbad(0, "requires UID 0");
252	}
253
254	mib[0] = CTL_NET;
255	mib[1] = PF_INET;
256	mib[2] = IPPROTO_IP;
257	mib[3] = IPCTL_FORWARDING;
258	len = sizeof(ipforwarding);
259	if (sysctl(mib, 4, &ipforwarding, &len, 0, 0) < 0)
260		LOGERR("sysctl(IPCTL_FORWARDING)");
261
262	if (!ipforwarding) {
263		if (supplier)
264			msglog("-s incompatible with ipforwarding=0");
265		if (default_gateway) {
266			msglog("-g incompatible with ipforwarding=0");
267			default_gateway = 0;
268		}
269		supplier = 0;
270		supplier_set = 1;
271	}
272	if (default_gateway) {
273		if (supplier_set && !supplier) {
274			msglog("-g and -q incompatible");
275		} else {
276			supplier = 1;
277			supplier_set = 1;
278		}
279	}
280
281
282	signal(SIGALRM, sigalrm);
283	if (!background)
284		signal(SIGHUP, sigterm);    /* SIGHUP fatal during debugging */
285	signal(SIGTERM, sigterm);
286	signal(SIGINT, sigterm);
287	signal(SIGUSR1, sigtrace_on);
288	signal(SIGUSR2, sigtrace_off);
289
290	/* get into the background */
291#ifdef sgi
292	if (0 > _daemonize(background ? 0 : (_DF_NOCHDIR|_DF_NOFORK),
293			   STDIN_FILENO, STDOUT_FILENO, STDERR_FILENO))
294		BADERR(0, "_daemonize()");
295#else
296	if (background && daemon(0, 1) < 0)
297		BADERR(0,"daemon()");
298#endif
299
300#if defined(__NetBSD__)
301	pidfile(NULL);
302#endif
303	mypid = getpid();
304
305	/* prepare socket connected to the kernel.
306	 */
307	rt_sock = socket(AF_ROUTE, SOCK_RAW, 0);
308	if (rt_sock < 0)
309		BADERR(1,"rt_sock = socket()");
310	if (fcntl(rt_sock, F_SETFL, O_NONBLOCK) == -1)
311		logbad(1, "fcntl(rt_sock) O_NONBLOCK: %s", strerror(errno));
312	off = 0;
313	if (setsockopt(rt_sock, SOL_SOCKET,SO_USELOOPBACK,
314		       &off,sizeof(off)) < 0)
315		LOGERR("setsockopt(SO_USELOOPBACK,0)");
316
317	fix_select();
318
319
320	if (tracename != 0) {
321		strlcpy(inittracename, tracename, sizeof(inittracename));
322		set_tracefile(inittracename, "%s", -1);
323	} else {
324		tracelevel_msg("%s", -1);   /* turn on tracing to stdio */
325	}
326
327	bufinit();
328
329	/* initialize radix tree */
330	rtinit();
331
332	/* Pick a random part of the second for our output to minimize
333	 * collisions.
334	 *
335	 * Start broadcasting after hearing from other routers, and
336	 * at a random time so a bunch of systems do not get synchronized
337	 * after a power failure.
338	 */
339	intvl_random(&next_bcast, EPOCH+MIN_WAITTIME, EPOCH+SUPPLY_INTERVAL);
340	age_timer.tv_usec = next_bcast.tv_usec;
341	age_timer.tv_sec = EPOCH+MIN_WAITTIME;
342	rdisc_timer = next_bcast;
343	ifinit_timer.tv_usec = next_bcast.tv_usec;
344
345	/* Collect an initial view of the world by checking the interface
346	 * configuration and the kludge file.
347	 */
348	gwkludge();
349	ifinit();
350
351	/* Ask for routes */
352	rip_query();
353	rdisc_sol();
354
355	/* Now turn off stdio if not tracing */
356	if (new_tracelevel == 0)
357		trace_close(background);
358
359	/* Loop forever, listening and broadcasting.
360	 */
361	for (;;) {
362		prev_clk = clk;
363		gettimeofday(&clk, 0);
364		if (prev_clk.tv_sec == clk.tv_sec
365		    && prev_clk.tv_usec == clk.tv_usec+usec_fudge) {
366			/* Much of `routed` depends on time always advancing.
367			 * On systems that do not guarantee that gettimeofday()
368			 * produces unique timestamps even if called within
369			 * a single tick, use trickery like that in classic
370			 * BSD kernels.
371			 */
372			clk.tv_usec += ++usec_fudge;
373
374		} else {
375			usec_fudge = 0;
376
377			timevalsub(&t2, &clk, &prev_clk);
378			if (t2.tv_sec < 0
379			    || t2.tv_sec > wtime.tv_sec + 5) {
380				/* Deal with time changes before other
381				 * housekeeping to keep everything straight.
382				 */
383				dt = t2.tv_sec;
384				if (dt > 0)
385					dt -= wtime.tv_sec;
386				trace_act("time changed by %d sec", (int)dt);
387				epoch.tv_sec += dt;
388			}
389		}
390		timevalsub(&now, &clk, &epoch);
391		now_stale = now.tv_sec - STALE_TIME;
392		now_expire = now.tv_sec - EXPIRE_TIME;
393		now_garbage = now.tv_sec - GARBAGE_TIME;
394
395		/* deal with signals that should affect tracing */
396		set_tracelevel();
397
398		if (stopint != 0) {
399			rip_bcast(0);
400			rdisc_adv();
401			trace_off("exiting with signal %d", stopint);
402			exit(stopint | 128);
403		}
404
405		/* look for new or dead interfaces */
406		timevalsub(&wtime, &ifinit_timer, &now);
407		if (wtime.tv_sec <= 0) {
408			wtime.tv_sec = 0;
409			ifinit();
410			rip_query();
411			continue;
412		}
413
414		/* Check the kernel table occassionally for mysteriously
415		 * evaporated routes
416		 */
417		timevalsub(&t2, &flush_kern_timer, &now);
418		if (t2.tv_sec <= 0) {
419			flush_kern();
420			flush_kern_timer.tv_sec = (now.tv_sec
421						   + CHECK_QUIET_INTERVAL);
422			continue;
423		}
424		if (timercmp(&t2, &wtime, <))
425			wtime = t2;
426
427		/* If it is time, then broadcast our routes.
428		 */
429		if (supplier || advertise_mhome) {
430			timevalsub(&t2, &next_bcast, &now);
431			if (t2.tv_sec <= 0) {
432				/* Synchronize the aging and broadcast
433				 * timers to minimize awakenings
434				 */
435				age(0);
436
437				rip_bcast(0);
438
439				/* It is desirable to send routing updates
440				 * regularly.  So schedule the next update
441				 * 30 seconds after the previous one was
442				 * scheduled, instead of 30 seconds after
443				 * the previous update was finished.
444				 * Even if we just started after discovering
445				 * a 2nd interface or were otherwise delayed,
446				 * pick a 30-second aniversary of the
447				 * original broadcast time.
448				 */
449				n = 1 + (0-t2.tv_sec)/SUPPLY_INTERVAL;
450				next_bcast.tv_sec += n*SUPPLY_INTERVAL;
451
452				continue;
453			}
454
455			if (timercmp(&t2, &wtime, <))
456				wtime = t2;
457		}
458
459		/* If we need a flash update, either do it now or
460		 * set the delay to end when it is time.
461		 *
462		 * If we are within MIN_WAITTIME seconds of a full update,
463		 * do not bother.
464		 */
465		if (need_flash
466		    && supplier
467		    && no_flash.tv_sec+MIN_WAITTIME < next_bcast.tv_sec) {
468			/* accurate to the millisecond */
469			if (!timercmp(&no_flash, &now, >))
470				rip_bcast(1);
471			timevalsub(&t2, &no_flash, &now);
472			if (timercmp(&t2, &wtime, <))
473				wtime = t2;
474		}
475
476		/* trigger the main aging timer.
477		 */
478		timevalsub(&t2, &age_timer, &now);
479		if (t2.tv_sec <= 0) {
480			age(0);
481			continue;
482		}
483		if (timercmp(&t2, &wtime, <))
484			wtime = t2;
485
486		/* update the kernel routing table
487		 */
488		timevalsub(&t2, &need_kern, &now);
489		if (t2.tv_sec <= 0) {
490			age(0);
491			continue;
492		}
493		if (timercmp(&t2, &wtime, <))
494			wtime = t2;
495
496		/* take care of router discovery,
497		 * but do it in the correct the millisecond
498		 */
499		if (!timercmp(&rdisc_timer, &now, >)) {
500			rdisc_age(0);
501			continue;
502		}
503		timevalsub(&t2, &rdisc_timer, &now);
504		if (timercmp(&t2, &wtime, <))
505			wtime = t2;
506
507
508		/* wait for input or a timer to expire.
509		 */
510		trace_flush();
511		if (ibitsp)
512			free(ibitsp);
513		ibitsp = (fd_set *)calloc(howmany(sock_max, NFDBITS),
514		    sizeof(fd_mask));
515		if (ibitsp == NULL)
516			BADERR(1, "calloc");
517		memcpy(ibitsp, fdbitsp, howmany(sock_max, NFDBITS) *
518		    sizeof(fd_mask));
519		n = select(sock_max, ibitsp, 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, ibitsp)) {
527			read_rt();
528			n--;
529		}
530		if (rdisc_sock >= 0 && FD_ISSET(rdisc_sock, ibitsp)) {
531			read_d();
532			n--;
533		}
534		if (rip_sock >= 0 && FD_ISSET(rip_sock, ibitsp)) {
535			read_rip(rip_sock, 0);
536			n--;
537		}
538
539		for (ifp = ifnet; n > 0 && 0 != ifp; ifp = ifp->int_next) {
540			if (ifp->int_rip_sock >= 0
541			    && FD_ISSET(ifp->int_rip_sock, ibitsp)) {
542				read_rip(ifp->int_rip_sock, ifp);
543				n--;
544			}
545		}
546	}
547}
548
549
550/* ARGSUSED */
551void
552sigalrm(int s UNUSED)
553{
554	/* Historically, SIGALRM would cause the daemon to check for
555	 * new and broken interfaces.
556	 */
557	ifinit_timer.tv_sec = now.tv_sec;
558	trace_act("SIGALRM");
559}
560
561
562/* watch for fatal signals */
563void
564sigterm(int sig)
565{
566	stopint = sig;
567	(void)signal(sig, SIG_DFL);	/* catch it only once */
568}
569
570
571void
572fix_select(void)
573{
574	struct interface *ifp;
575
576	sock_max = 0;
577
578	if (sock_max <= rt_sock)
579		sock_max = rt_sock + 1;
580	if (rip_sock >= 0)
581		if (sock_max <= rip_sock)
582			sock_max = rip_sock + 1;
583	for (ifp = ifnet; 0 != ifp; ifp = ifp->int_next) {
584		if (ifp->int_rip_sock >= 0)
585			if (sock_max <= ifp->int_rip_sock)
586				sock_max = ifp->int_rip_sock + 1;
587	}
588	if (rdisc_sock >= 0)
589		if (sock_max <= rdisc_sock)
590			sock_max = rdisc_sock + 1;
591
592	if (fdbitsp)
593		free(fdbitsp);
594	fdbitsp = (fd_set *)calloc(howmany(sock_max, NFDBITS),
595	    sizeof(fd_mask));
596	if (fdbitsp == NULL)
597		BADERR(1, "calloc");
598
599	FD_SET(rt_sock, fdbitsp);
600	if (rip_sock >= 0)
601		FD_SET(rip_sock, fdbitsp);
602	for (ifp = ifnet; 0 != ifp; ifp = ifp->int_next) {
603		if (ifp->int_rip_sock >= 0)
604			FD_SET(ifp->int_rip_sock, fdbitsp);
605	}
606	if (rdisc_sock >= 0)
607		FD_SET(rdisc_sock, fdbitsp);
608}
609
610
611void
612fix_sock(int sock,
613	 const char *name)
614{
615	int on;
616#define MIN_SOCKBUF (4*1024)
617	static int rbuf;
618
619	if (fcntl(sock, F_SETFL, O_NONBLOCK) == -1)
620		logbad(1, "fcntl(%s) O_NONBLOCK: %s",
621		       name, strerror(errno));
622	on = 1;
623	if (setsockopt(sock, SOL_SOCKET,SO_BROADCAST, &on,sizeof(on)) < 0)
624		msglog("setsockopt(%s,SO_BROADCAST): %s",
625		       name, strerror(errno));
626#ifdef USE_PASSIFNAME
627	on = 1;
628	if (setsockopt(sock, SOL_SOCKET, SO_PASSIFNAME, &on,sizeof(on)) < 0)
629		msglog("setsockopt(%s,SO_PASSIFNAME): %s",
630		       name, strerror(errno));
631#endif
632
633	if (rbuf >= MIN_SOCKBUF) {
634		if (setsockopt(sock, SOL_SOCKET, SO_RCVBUF,
635			       &rbuf, sizeof(rbuf)) < 0)
636			msglog("setsockopt(%s,SO_RCVBUF=%d): %s",
637			       name, rbuf, strerror(errno));
638	} else {
639		for (rbuf = 60*1024; ; rbuf -= 4096) {
640			if (setsockopt(sock, SOL_SOCKET, SO_RCVBUF,
641				       &rbuf, sizeof(rbuf)) == 0) {
642				trace_act("RCVBUF=%d", rbuf);
643				break;
644			}
645			if (rbuf < MIN_SOCKBUF) {
646				msglog("setsockopt(%s,SO_RCVBUF = %d): %s",
647				       name, rbuf, strerror(errno));
648				break;
649			}
650		}
651	}
652}
653
654
655/* get a rip socket
656 */
657static int				/* <0 or file descriptor */
658get_rip_sock(naddr addr,
659	     int serious)		/* 1=failure to bind is serious */
660{
661	struct sockaddr_in rsin;
662	unsigned char ttl;
663	int s;
664
665
666	if ((s = socket(AF_INET, SOCK_DGRAM, 0)) < 0)
667		BADERR(1,"rip_sock = socket()");
668
669	memset(&rsin, 0, sizeof(rsin));
670#ifdef _HAVE_SIN_LEN
671	rsin.sin_len = sizeof(rsin);
672#endif
673	rsin.sin_family = AF_INET;
674	rsin.sin_port = htons(RIP_PORT);
675	rsin.sin_addr.s_addr = addr;
676	if (bind(s, (struct sockaddr *)&rsin, sizeof(rsin)) < 0) {
677		if (serious)
678			BADERR(errno != EADDRINUSE, "bind(rip_sock)");
679		return -1;
680	}
681	fix_sock(s,"rip_sock");
682
683	ttl = 1;
684	if (setsockopt(s, IPPROTO_IP, IP_MULTICAST_TTL,
685		       &ttl, sizeof(ttl)) < 0)
686		DBGERR(1,"rip_sock setsockopt(IP_MULTICAST_TTL)");
687
688	return s;
689}
690
691
692/* turn off main RIP socket */
693void
694rip_off(void)
695{
696	struct interface *ifp;
697	naddr addr;
698
699
700	if (rip_sock >= 0 && !mhome) {
701		trace_act("turn off RIP");
702
703		(void)close(rip_sock);
704		rip_sock = -1;
705
706		/* get non-broadcast sockets to listen to queries.
707		 */
708		for (ifp = ifnet; ifp != 0; ifp = ifp->int_next) {
709			if (ifp->int_state & IS_REMOTE)
710				continue;
711			if (ifp->int_rip_sock < 0) {
712				addr = ((ifp->int_if_flags & IFF_POINTOPOINT)
713					? ifp->int_dstaddr
714					: ifp->int_addr);
715				ifp->int_rip_sock = get_rip_sock(addr, 0);
716			}
717		}
718
719		fix_select();
720
721		age(0);
722	}
723}
724
725
726/* turn on RIP multicast input via an interface
727 */
728static void
729rip_mcast_on(struct interface *ifp)
730{
731	struct ip_mreq m;
732
733	if (!IS_RIP_IN_OFF(ifp->int_state)
734	    && (ifp->int_if_flags & IFF_MULTICAST)
735#ifdef MCAST_PPP_BUG
736	    && !(ifp->int_if_flags & IFF_POINTOPOINT)
737#endif
738	    && !(ifp->int_state & IS_ALIAS)) {
739		m.imr_multiaddr.s_addr = htonl(INADDR_RIP_GROUP);
740#ifdef MCAST_IFINDEX
741		m.imr_interface.s_addr = htonl(ifp->int_index);
742#else
743		m.imr_interface.s_addr = ((ifp->int_if_flags & IFF_POINTOPOINT)
744					  ? ifp->int_dstaddr
745					  : ifp->int_addr);
746#endif
747		if (setsockopt(rip_sock,IPPROTO_IP, IP_ADD_MEMBERSHIP,
748			       &m, sizeof(m)) < 0)
749			LOGERR("setsockopt(IP_ADD_MEMBERSHIP RIP)");
750	}
751}
752
753
754/* Prepare socket used for RIP.
755 */
756void
757rip_on(struct interface *ifp)
758{
759	/* If the main RIP socket is already alive, only start receiving
760	 * multicasts for this interface.
761	 */
762	if (rip_sock >= 0) {
763		if (ifp != 0)
764			rip_mcast_on(ifp);
765		return;
766	}
767
768	/* If the main RIP socket is off and it makes sense to turn it on,
769	 * then turn it on for all of the interfaces.
770	 * It makes sense if either router discovery is off, or if
771	 * router discover is on and at most one interface is doing RIP.
772	 */
773	if (rip_interfaces > 0 && (!rdisc_ok || rip_interfaces > 1)) {
774		trace_act("turn on RIP");
775
776		/* Close all of the query sockets so that we can open
777		 * the main socket.  SO_REUSEPORT is not a solution,
778		 * since that would let two daemons bind to the broadcast
779		 * socket.
780		 */
781		for (ifp = ifnet; ifp != 0; ifp = ifp->int_next) {
782			if (ifp->int_rip_sock >= 0) {
783				(void)close(ifp->int_rip_sock);
784				ifp->int_rip_sock = -1;
785			}
786		}
787
788		rip_sock = get_rip_sock(INADDR_ANY, 1);
789		rip_sock_mcast = 0;
790
791		/* Do not advertise anything until we have heard something
792		 */
793		if (next_bcast.tv_sec < now.tv_sec+MIN_WAITTIME)
794			next_bcast.tv_sec = now.tv_sec+MIN_WAITTIME;
795
796		for (ifp = ifnet; ifp != 0; ifp = ifp->int_next) {
797			ifp->int_query_time = NEVER;
798			rip_mcast_on(ifp);
799		}
800		ifinit_timer.tv_sec = now.tv_sec;
801
802	} else if (ifp != 0
803		   && !(ifp->int_state & IS_REMOTE)
804		   && ifp->int_rip_sock < 0) {
805		/* RIP is off, so ensure there are sockets on which
806		 * to listen for queries.
807		 */
808		ifp->int_rip_sock = get_rip_sock(ifp->int_addr, 0);
809	}
810
811	fix_select();
812}
813
814
815/* die if malloc(3) fails
816 */
817void *
818rtmalloc(size_t size,
819	 const char *msg)
820{
821	void *p = malloc(size);
822	if (p == 0)
823		logbad(1,"malloc(%lu) failed in %s", (u_long)size, msg);
824	return p;
825}
826
827
828/* get a random instant in an interval
829 */
830void
831intvl_random(struct timeval *tp,	/* put value here */
832	     u_long lo,			/* value is after this second */
833	     u_long hi)			/* and before this */
834{
835	tp->tv_sec = (time_t)(hi == lo
836			      ? lo
837			      : (lo + arc4random() % ((hi - lo))));
838	tp->tv_usec = arc4random() % 1000000;
839}
840
841
842void
843timevaladd(struct timeval *t1,
844	   struct timeval *t2)
845{
846
847	t1->tv_sec += t2->tv_sec;
848	if ((t1->tv_usec += t2->tv_usec) >= 1000000) {
849		t1->tv_sec++;
850		t1->tv_usec -= 1000000;
851	}
852}
853
854
855/* t1 = t2 - t3
856 */
857static void
858timevalsub(struct timeval *t1,
859	   struct timeval *t2,
860	   struct timeval *t3)
861{
862	t1->tv_sec = t2->tv_sec - t3->tv_sec;
863	if ((t1->tv_usec = t2->tv_usec - t3->tv_usec) < 0) {
864		t1->tv_sec--;
865		t1->tv_usec += 1000000;
866	}
867}
868
869
870/* put a message into the system log
871 */
872void
873msglog(const char *p, ...)
874{
875	va_list args;
876
877	trace_flush();
878
879	va_start(args, p);
880	vsyslog(LOG_ERR, p, args);
881	va_end(args);
882
883	if (ftrace != 0) {
884		if (ftrace == stdout)
885			(void)fputs("routed: ", ftrace);
886		va_start(args, p);
887		(void)vfprintf(ftrace, p, args);
888		va_end(args);
889		(void)fputc('\n', ftrace);
890	}
891}
892
893
894/* Put a message about a bad system into the system log if
895 * we have not complained about it recently.
896 *
897 * It is desirable to complain about all bad systems, but not too often.
898 * In the worst case, it is not practical to keep track of all bad systems.
899 * For example, there can be many systems with the wrong password.
900 */
901void
902msglim(struct msg_limit *lim, naddr addr, const char *p, ...)
903{
904	va_list args;
905	int i;
906	struct msg_sub *ms1, *ms;
907	const char *p1;
908
909	/* look for the oldest slot in the table
910	 * or the slot for the bad router.
911	 */
912	ms = ms1 = lim->subs;
913	for (i = MSG_SUBJECT_N; ; i--, ms1++) {
914		if (i == 0) {
915			/* Reuse a slot at most once every 10 minutes.
916			 */
917			if (lim->reuse > now.tv_sec) {
918				ms = 0;
919			} else {
920				ms = ms1;
921				lim->reuse = now.tv_sec + 10*60;
922			}
923			break;
924		}
925		if (ms->addr == addr) {
926			/* Repeat a complaint about a given system at
927			 * most once an hour.
928			 */
929			if (ms->until > now.tv_sec)
930				ms = 0;
931			break;
932		}
933		if (ms->until < ms1->until)
934			ms = ms1;
935	}
936	if (ms != 0) {
937		ms->addr = addr;
938		ms->until = now.tv_sec + 60*60;	/* 60 minutes */
939
940		trace_flush();
941		for (p1 = p; *p1 == ' '; p1++)
942			continue;
943		va_start(args, p);
944		vsyslog(LOG_ERR, p1, args);
945		va_end(args);
946	}
947
948	/* always display the message if tracing */
949	if (ftrace != 0) {
950		va_start(args, p);
951		(void)vfprintf(ftrace, p, args);
952		(void)fputc('\n', ftrace);
953		va_end(args);
954	}
955}
956
957
958void
959logbad(int dump, const char *p, ...)
960{
961	va_list args;
962
963	trace_flush();
964
965	va_start(args, p);
966	vsyslog(LOG_ERR, p, args);
967	va_end(args);
968
969	(void)fputs("routed: ", stderr);
970	va_start(args, p);
971	(void)vfprintf(stderr, p, args);
972	va_end(args);
973	(void)fputs("; giving up\n",stderr);
974	(void)fflush(stderr);
975
976	if (dump)
977		abort();
978	exit(1);
979}
980