xref: /netbsd-src/sbin/routed/main.c (revision bada23909e740596d0a3785a73bd3583a9807fb8)
1 /*	$NetBSD: main.c,v 1.22 1999/02/25 10:56:47 ross 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 #if !defined(lint) && !defined(sgi) && !defined(__NetBSD__)
37 static char sccsid[] __attribute__((unused)) = "@(#)main.c	8.1 (Berkeley) 6/5/93";
38 #define __COPYRIGHT(a) char copyright[] = a;
39 #elif defined(__NetBSD__)
40 #include <sys/cdefs.h>
41 __RCSID("$NetBSD: main.c,v 1.22 1999/02/25 10:56:47 ross Exp $");
42 #endif
43 __COPYRIGHT("@(#) Copyright (c) 1983, 1988, 1993\n\
44 	The Regents of the University of California.  All rights reserved.\n");
45 
46 #include "defs.h"
47 #include "pathnames.h"
48 #ifdef sgi
49 #include "math.h"
50 #endif
51 #include <signal.h>
52 #include <fcntl.h>
53 #include <sys/file.h>
54 
55 pid_t	mypid;
56 
57 naddr	myaddr;				/* system address */
58 char	myname[MAXHOSTNAMELEN+1];
59 
60 int	verbose;
61 
62 int	supplier;			/* supply or broadcast updates */
63 int	supplier_set;
64 int	ipforwarding = 1;		/* kernel forwarding on */
65 
66 int	default_gateway;		/* 1=advertise default */
67 int	background = 1;
68 int	ridhosts;			/* 1=reduce host routes */
69 int	mhome;				/* 1=want multi-homed host route */
70 int	advertise_mhome;		/* 1=must continue advertising it */
71 int	auth_ok = 1;			/* 1=ignore auth if we do not care */
72 
73 struct timeval epoch;			/* when started */
74 struct timeval clk, prev_clk;
75 struct timeval now;			/* current idea of time */
76 time_t	now_stale;
77 time_t	now_expire;
78 time_t	now_garbage;
79 
80 struct timeval next_bcast;		/* next general broadcast */
81 struct timeval no_flash = {EPOCH+SUPPLY_INTERVAL};  /* inhibit flash update */
82 
83 struct timeval flush_kern_timer;
84 
85 fd_set	fdbits;
86 int	sock_max;
87 int	rip_sock = -1;			/* RIP socket */
88 struct interface *rip_sock_mcast;	/* current multicast interface */
89 int	rt_sock;			/* routing socket */
90 int	rt_sock_seqno;
91 
92 
93 static  int get_rip_sock(naddr, int);
94 static void timevalsub(struct timeval *, struct timeval *, struct timeval *);
95 
96 int
97 main(int argc,
98      char *argv[])
99 {
100 	int n, mib[4], off;
101 	size_t len;
102 	char *p, *q;
103 	const char *cp;
104 	struct timeval wtime, t2;
105 	time_t dt;
106 	fd_set ibits;
107 	naddr p_net, p_mask;
108 	struct interface *ifp;
109 	struct parm parm;
110 	char *tracename = 0;
111 
112 
113 	/* Some shells are badly broken and send SIGHUP to backgrounded
114 	 * processes.
115 	 */
116 	signal(SIGHUP, SIG_IGN);
117 
118 	openlog("routed", LOG_PID | LOG_ODELAY, LOG_DAEMON);
119 	ftrace = stdout;
120 
121 	gettimeofday(&clk, 0);
122 	prev_clk = clk;
123 	epoch = clk;
124 	epoch.tv_sec -= EPOCH;
125 	now.tv_sec = EPOCH;
126 	now_stale = EPOCH - STALE_TIME;
127 	now_expire = EPOCH - EXPIRE_TIME;
128 	now_garbage = EPOCH - GARBAGE_TIME;
129 	wtime.tv_sec = 0;
130 
131 	(void)gethostname(myname, sizeof(myname));
132 	myname[sizeof(myname) - 1] = '\0';
133 	(void)gethost(myname, &myaddr);
134 
135 	while ((n = getopt(argc, argv, "sqdghmpAtvT:F:P:")) != -1) {
136 		switch (n) {
137 		case 's':
138 			supplier = 1;
139 			supplier_set = 1;
140 			break;
141 
142 		case 'q':
143 			supplier = 0;
144 			supplier_set = 1;
145 			break;
146 
147 		case 'd':
148 			background = 0;
149 			break;
150 
151 		case 'g':
152 			memset(&parm, 0, sizeof(parm));
153 			parm.parm_d_metric = 1;
154 			cp = check_parms(&parm);
155 			if (cp != 0)
156 				msglog("bad -g: %s", cp);
157 			else
158 				default_gateway = 1;
159 			break;
160 
161 		case 'h':		/* suppress extra host routes */
162 			ridhosts = 1;
163 			break;
164 
165 		case 'm':		/* advertise host route */
166 			mhome = 1;	/* on multi-homed hosts */
167 			break;
168 
169 		case 'A':
170 			/* Ignore authentication if we do not care.
171 			 * Crazy as it is, that is what RFC 1723 requires.
172 			 */
173 			auth_ok = 0;
174 			break;
175 
176 		case 't':
177 			new_tracelevel++;
178 			break;
179 
180 		case 'T':
181 			tracename = optarg;
182 			break;
183 
184 		case 'F':		/* minimal routes for SLIP */
185 			n = FAKE_METRIC;
186 			p = strchr(optarg,',');
187 			if (p && *p != '\0') {
188 				n = (int)strtoul(p+1, &q, 0);
189 				if (*q == '\0'
190 				    && n <= HOPCNT_INFINITY-1
191 				    && n >= 1)
192 					*p = '\0';
193 			}
194 			if (!getnet(optarg, &p_net, &p_mask)) {
195 				msglog("bad network; \"-F %s\"",
196 				       optarg);
197 				break;
198 			}
199 			memset(&parm, 0, sizeof(parm));
200 			parm.parm_net = p_net;
201 			parm.parm_mask = p_mask;
202 			parm.parm_d_metric = n;
203 			cp = check_parms(&parm);
204 			if (cp != 0)
205 				msglog("bad -F: %s", cp);
206 			break;
207 
208 		case 'P':
209 			/* handle arbitrary parameters.
210 			 */
211 			q = strdup(optarg);
212 			cp = parse_parms(q, 0);
213 			if (cp != 0)
214 				msglog("%s in \"-P %s\"", cp, optarg);
215 			free(q);
216 			break;
217 
218 		case 'v':
219 			/* display version */
220 			verbose++;
221 			msglog("version 2.16");
222 			break;
223 
224 		default:
225 			goto usage;
226 		}
227 	}
228 	argc -= optind;
229 	argv += optind;
230 
231 	if (tracename == 0 && argc >= 1) {
232 		tracename = *argv++;
233 		argc--;
234 	}
235 	if (tracename != 0 && tracename[0] == '\0')
236 		goto usage;
237 	if (argc != 0) {
238 usage:
239 		logbad(0, "usage: routed [-sqdghmpAtv] [-T tracefile]"
240 		       " [-F net[,metric]] [-P parms]");
241 	}
242 	if (geteuid() != 0) {
243 		if (verbose)
244 			exit(0);
245 		logbad(0, "requires UID 0");
246 	}
247 
248 	mib[0] = CTL_NET;
249 	mib[1] = PF_INET;
250 	mib[2] = IPPROTO_IP;
251 	mib[3] = IPCTL_FORWARDING;
252 	len = sizeof(ipforwarding);
253 	if (sysctl(mib, 4, &ipforwarding, &len, 0, 0) < 0)
254 		LOGERR("sysctl(IPCTL_FORWARDING)");
255 
256 	if (!ipforwarding) {
257 		if (supplier)
258 			msglog("-s incompatible with ipforwarding=0");
259 		if (default_gateway) {
260 			msglog("-g incompatible with ipforwarding=0");
261 			default_gateway = 0;
262 		}
263 		supplier = 0;
264 		supplier_set = 1;
265 	}
266 	if (default_gateway) {
267 		if (supplier_set && !supplier) {
268 			msglog("-g and -q incompatible");
269 		} else {
270 			supplier = 1;
271 			supplier_set = 1;
272 		}
273 	}
274 
275 
276 	signal(SIGALRM, sigalrm);
277 	if (!background)
278 		signal(SIGHUP, sigterm);    /* SIGHUP fatal during debugging */
279 	signal(SIGTERM, sigterm);
280 	signal(SIGINT, sigterm);
281 	signal(SIGUSR1, sigtrace_on);
282 	signal(SIGUSR2, sigtrace_off);
283 
284 	/* get into the background */
285 #ifdef sgi
286 	if (0 > _daemonize(background ? 0 : (_DF_NOCHDIR|_DF_NOFORK),
287 			   STDIN_FILENO, STDOUT_FILENO, STDERR_FILENO))
288 		BADERR(0, "_daemonize()");
289 #else
290 	if (background && daemon(0, 1) < 0)
291 		BADERR(0,"daemon()");
292 #endif
293 
294 	mypid = getpid();
295 	srandom((int)(clk.tv_sec ^ clk.tv_usec ^ mypid));
296 
297 	/* prepare socket connected to the kernel.
298 	 */
299 	rt_sock = socket(AF_ROUTE, SOCK_RAW, 0);
300 	if (rt_sock < 0)
301 		BADERR(1,"rt_sock = socket()");
302 	if (fcntl(rt_sock, F_SETFL, O_NONBLOCK) == -1)
303 		logbad(1, "fcntl(rt_sock) O_NONBLOCK: %s", strerror(errno));
304 	off = 0;
305 	if (setsockopt(rt_sock, SOL_SOCKET,SO_USELOOPBACK,
306 		       &off,sizeof(off)) < 0)
307 		LOGERR("setsockopt(SO_USELOOPBACK,0)");
308 
309 	fix_select();
310 
311 
312 	if (tracename != 0) {
313 		strncpy(inittracename, tracename, sizeof(inittracename)-1);
314 		set_tracefile(inittracename, "%s", -1);
315 	} else {
316 		tracelevel_msg("%s", -1);   /* turn on tracing to stdio */
317 	}
318 
319 	bufinit();
320 
321 	/* initialize radix tree */
322 	rtinit();
323 
324 	/* Pick a random part of the second for our output to minimize
325 	 * collisions.
326 	 *
327 	 * Start broadcasting after hearing from other routers, and
328 	 * at a random time so a bunch of systems do not get synchronized
329 	 * after a power failure.
330 	 */
331 	intvl_random(&next_bcast, EPOCH+MIN_WAITTIME, EPOCH+SUPPLY_INTERVAL);
332 	age_timer.tv_usec = next_bcast.tv_usec;
333 	age_timer.tv_sec = EPOCH+MIN_WAITTIME;
334 	rdisc_timer = next_bcast;
335 	ifinit_timer.tv_usec = next_bcast.tv_usec;
336 
337 	/* Collect an initial view of the world by checking the interface
338 	 * configuration and the kludge file.
339 	 */
340 	gwkludge();
341 	ifinit();
342 
343 	/* Ask for routes */
344 	rip_query();
345 	rdisc_sol();
346 
347 	/* Now turn off stdio if not tracing */
348 	if (new_tracelevel == 0)
349 		trace_close(background);
350 
351 	/* Loop forever, listening and broadcasting.
352 	 */
353 	for (;;) {
354 		prev_clk = clk;
355 		gettimeofday(&clk, 0);
356 		timevalsub(&t2, &clk, &prev_clk);
357 		if (t2.tv_sec < 0
358 		    || t2.tv_sec > wtime.tv_sec + 5) {
359 			/* Deal with time changes before other housekeeping to
360 			 * keep everything straight.
361 			 */
362 			dt = t2.tv_sec;
363 			if (dt > 0)
364 				dt -= wtime.tv_sec;
365 			trace_act("time changed by %d sec", (int)dt);
366 			epoch.tv_sec += dt;
367 		}
368 		timevalsub(&now, &clk, &epoch);
369 		now_stale = now.tv_sec - STALE_TIME;
370 		now_expire = now.tv_sec - EXPIRE_TIME;
371 		now_garbage = now.tv_sec - GARBAGE_TIME;
372 
373 		/* deal with signals that should affect tracing */
374 		set_tracelevel();
375 
376 		if (stopint != 0) {
377 			rip_bcast(0);
378 			rdisc_adv();
379 			trace_off("exiting with signal %d", stopint);
380 			exit(stopint | 128);
381 		}
382 
383 		/* look for new or dead interfaces */
384 		timevalsub(&wtime, &ifinit_timer, &now);
385 		if (wtime.tv_sec <= 0) {
386 			wtime.tv_sec = 0;
387 			ifinit();
388 			rip_query();
389 			continue;
390 		}
391 
392 		/* Check the kernel table occassionally for mysteriously
393 		 * evaporated routes
394 		 */
395 		timevalsub(&t2, &flush_kern_timer, &now);
396 		if (t2.tv_sec <= 0) {
397 			flush_kern();
398 			flush_kern_timer.tv_sec = (now.tv_sec
399 						   + CHECK_QUIET_INTERVAL);
400 			continue;
401 		}
402 		if (timercmp(&t2, &wtime, <))
403 			wtime = t2;
404 
405 		/* If it is time, then broadcast our routes.
406 		 */
407 		if (supplier || advertise_mhome) {
408 			timevalsub(&t2, &next_bcast, &now);
409 			if (t2.tv_sec <= 0) {
410 				/* Synchronize the aging and broadcast
411 				 * timers to minimize awakenings
412 				 */
413 				age(0);
414 
415 				rip_bcast(0);
416 
417 				/* It is desirable to send routing updates
418 				 * regularly.  So schedule the next update
419 				 * 30 seconds after the previous one was
420 				 * scheduled, instead of 30 seconds after
421 				 * the previous update was finished.
422 				 * Even if we just started after discovering
423 				 * a 2nd interface or were otherwise delayed,
424 				 * pick a 30-second aniversary of the
425 				 * original broadcast time.
426 				 */
427 				n = 1 + (0-t2.tv_sec)/SUPPLY_INTERVAL;
428 				next_bcast.tv_sec += n*SUPPLY_INTERVAL;
429 
430 				continue;
431 			}
432 
433 			if (timercmp(&t2, &wtime, <))
434 				wtime = t2;
435 		}
436 
437 		/* If we need a flash update, either do it now or
438 		 * set the delay to end when it is time.
439 		 *
440 		 * If we are within MIN_WAITTIME seconds of a full update,
441 		 * do not bother.
442 		 */
443 		if (need_flash
444 		    && supplier
445 		    && no_flash.tv_sec+MIN_WAITTIME < next_bcast.tv_sec) {
446 			/* accurate to the millisecond */
447 			if (!timercmp(&no_flash, &now, >))
448 				rip_bcast(1);
449 			timevalsub(&t2, &no_flash, &now);
450 			if (timercmp(&t2, &wtime, <))
451 				wtime = t2;
452 		}
453 
454 		/* trigger the main aging timer.
455 		 */
456 		timevalsub(&t2, &age_timer, &now);
457 		if (t2.tv_sec <= 0) {
458 			age(0);
459 			continue;
460 		}
461 		if (timercmp(&t2, &wtime, <))
462 			wtime = t2;
463 
464 		/* update the kernel routing table
465 		 */
466 		timevalsub(&t2, &need_kern, &now);
467 		if (t2.tv_sec <= 0) {
468 			age(0);
469 			continue;
470 		}
471 		if (timercmp(&t2, &wtime, <))
472 			wtime = t2;
473 
474 		/* take care of router discovery,
475 		 * but do it in the correct the millisecond
476 		 */
477 		if (!timercmp(&rdisc_timer, &now, >)) {
478 			rdisc_age(0);
479 			continue;
480 		}
481 		timevalsub(&t2, &rdisc_timer, &now);
482 		if (timercmp(&t2, &wtime, <))
483 			wtime = t2;
484 
485 
486 		/* wait for input or a timer to expire.
487 		 */
488 		trace_flush();
489 		ibits = fdbits;
490 		n = select(sock_max, &ibits, 0, 0, &wtime);
491 		if (n <= 0) {
492 			if (n < 0 && errno != EINTR && errno != EAGAIN)
493 				BADERR(1,"select");
494 			continue;
495 		}
496 
497 		if (FD_ISSET(rt_sock, &ibits)) {
498 			read_rt();
499 			n--;
500 		}
501 		if (rdisc_sock >= 0 && FD_ISSET(rdisc_sock, &ibits)) {
502 			read_d();
503 			n--;
504 		}
505 		if (rip_sock >= 0 && FD_ISSET(rip_sock, &ibits)) {
506 			read_rip(rip_sock, 0);
507 			n--;
508 		}
509 
510 		for (ifp = ifnet; n > 0 && 0 != ifp; ifp = ifp->int_next) {
511 			if (ifp->int_rip_sock >= 0
512 			    && FD_ISSET(ifp->int_rip_sock, &ibits)) {
513 				read_rip(ifp->int_rip_sock, ifp);
514 				n--;
515 			}
516 		}
517 	}
518 }
519 
520 
521 /* ARGSUSED */
522 void
523 sigalrm(int s UNUSED)
524 {
525 	/* Historically, SIGALRM would cause the daemon to check for
526 	 * new and broken interfaces.
527 	 */
528 	ifinit_timer.tv_sec = now.tv_sec;
529 	trace_act("SIGALRM");
530 }
531 
532 
533 /* watch for fatal signals */
534 void
535 sigterm(int sig)
536 {
537 	stopint = sig;
538 	(void)signal(sig, SIG_DFL);	/* catch it only once */
539 }
540 
541 
542 void
543 fix_select(void)
544 {
545 	struct interface *ifp;
546 
547 
548 	FD_ZERO(&fdbits);
549 	sock_max = 0;
550 
551 	FD_SET(rt_sock, &fdbits);
552 	if (sock_max <= rt_sock)
553 		sock_max = rt_sock+1;
554 	if (rip_sock >= 0) {
555 		FD_SET(rip_sock, &fdbits);
556 		if (sock_max <= rip_sock)
557 			sock_max = rip_sock+1;
558 	}
559 	for (ifp = ifnet; 0 != ifp; ifp = ifp->int_next) {
560 		if (ifp->int_rip_sock >= 0) {
561 			FD_SET(ifp->int_rip_sock, &fdbits);
562 			if (sock_max <= ifp->int_rip_sock)
563 				sock_max = ifp->int_rip_sock+1;
564 		}
565 	}
566 	if (rdisc_sock >= 0) {
567 		FD_SET(rdisc_sock, &fdbits);
568 		if (sock_max <= rdisc_sock)
569 			sock_max = rdisc_sock+1;
570 	}
571 }
572 
573 
574 void
575 fix_sock(int sock,
576 	 const char *name)
577 {
578 	int on;
579 #define MIN_SOCKBUF (4*1024)
580 	static int rbuf;
581 
582 	if (fcntl(sock, F_SETFL, O_NONBLOCK) == -1)
583 		logbad(1, "fcntl(%s) O_NONBLOCK: %s",
584 		       name, strerror(errno));
585 	on = 1;
586 	if (setsockopt(sock, SOL_SOCKET,SO_BROADCAST, &on,sizeof(on)) < 0)
587 		msglog("setsockopt(%s,SO_BROADCAST): %s",
588 		       name, strerror(errno));
589 #ifdef USE_PASSIFNAME
590 	on = 1;
591 	if (setsockopt(sock, SOL_SOCKET, SO_PASSIFNAME, &on,sizeof(on)) < 0)
592 		msglog("setsockopt(%s,SO_PASSIFNAME): %s",
593 		       name, strerror(errno));
594 #endif
595 
596 	if (rbuf >= MIN_SOCKBUF) {
597 		if (setsockopt(sock, SOL_SOCKET, SO_RCVBUF,
598 			       &rbuf, sizeof(rbuf)) < 0)
599 			msglog("setsockopt(%s,SO_RCVBUF=%d): %s",
600 			       name, rbuf, strerror(errno));
601 	} else {
602 		for (rbuf = 60*1024; ; rbuf -= 4096) {
603 			if (setsockopt(sock, SOL_SOCKET, SO_RCVBUF,
604 				       &rbuf, sizeof(rbuf)) == 0) {
605 				trace_act("RCVBUF=%d", rbuf);
606 				break;
607 			}
608 			if (rbuf < MIN_SOCKBUF) {
609 				msglog("setsockopt(%s,SO_RCVBUF = %d): %s",
610 				       name, rbuf, strerror(errno));
611 				break;
612 			}
613 		}
614 	}
615 }
616 
617 
618 /* get a rip socket
619  */
620 static int				/* <0 or file descriptor */
621 get_rip_sock(naddr addr,
622 	     int serious)		/* 1=failure to bind is serious */
623 {
624 	struct sockaddr_in sin;
625 	unsigned char ttl;
626 	int s;
627 
628 
629 	if ((s = socket(AF_INET, SOCK_DGRAM, 0)) < 0)
630 		BADERR(1,"rip_sock = socket()");
631 
632 	memset(&sin, 0, sizeof(sin));
633 #ifdef _HAVE_SIN_LEN
634 	sin.sin_len = sizeof(sin);
635 #endif
636 	sin.sin_family = AF_INET;
637 	sin.sin_port = htons(RIP_PORT);
638 	sin.sin_addr.s_addr = addr;
639 	if (bind(s, (struct sockaddr *)&sin, sizeof(sin)) < 0) {
640 		if (serious)
641 			BADERR(errno != EADDRINUSE, "bind(rip_sock)");
642 		return -1;
643 	}
644 	fix_sock(s,"rip_sock");
645 
646 	ttl = 1;
647 	if (setsockopt(s, IPPROTO_IP, IP_MULTICAST_TTL,
648 		       &ttl, sizeof(ttl)) < 0)
649 		DBGERR(1,"rip_sock setsockopt(IP_MULTICAST_TTL)");
650 
651 	return s;
652 }
653 
654 
655 /* turn off main RIP socket */
656 void
657 rip_off(void)
658 {
659 	struct interface *ifp;
660 	naddr addr;
661 
662 
663 	if (rip_sock >= 0 && !mhome) {
664 		trace_act("turn off RIP");
665 
666 		(void)close(rip_sock);
667 		rip_sock = -1;
668 
669 		/* get non-broadcast sockets to listen to queries.
670 		 */
671 		for (ifp = ifnet; ifp != 0; ifp = ifp->int_next) {
672 			if (ifp->int_state & IS_REMOTE)
673 				continue;
674 			if (ifp->int_rip_sock < 0) {
675 				addr = ((ifp->int_if_flags & IFF_POINTOPOINT)
676 					? ifp->int_dstaddr
677 					: ifp->int_addr);
678 				ifp->int_rip_sock = get_rip_sock(addr, 0);
679 			}
680 		}
681 
682 		fix_select();
683 
684 		age(0);
685 	}
686 }
687 
688 
689 /* turn on RIP multicast input via an interface
690  */
691 static void
692 rip_mcast_on(struct interface *ifp)
693 {
694 	struct ip_mreq m;
695 
696 	if (!IS_RIP_IN_OFF(ifp->int_state)
697 	    && (ifp->int_if_flags & IFF_MULTICAST)
698 #ifdef MCAST_PPP_BUG
699 	    && !(ifp->int_if_flags & IFF_POINTOPOINT)
700 #endif
701 	    && !(ifp->int_state & IS_ALIAS)) {
702 		m.imr_multiaddr.s_addr = htonl(INADDR_RIP_GROUP);
703 		m.imr_interface.s_addr = ((ifp->int_if_flags & IFF_POINTOPOINT)
704 					  ? ifp->int_dstaddr
705 					  : ifp->int_addr);
706 		if (setsockopt(rip_sock,IPPROTO_IP, IP_ADD_MEMBERSHIP,
707 			       &m, sizeof(m)) < 0)
708 			LOGERR("setsockopt(IP_ADD_MEMBERSHIP RIP)");
709 	}
710 }
711 
712 
713 /* Prepare socket used for RIP.
714  */
715 void
716 rip_on(struct interface *ifp)
717 {
718 	/* If the main RIP socket is already alive, only start receiving
719 	 * multicasts for this interface.
720 	 */
721 	if (rip_sock >= 0) {
722 		if (ifp != 0)
723 			rip_mcast_on(ifp);
724 		return;
725 	}
726 
727 	/* If the main RIP socket is off and it makes sense to turn it on,
728 	 * then turn it on for all of the interfaces.
729 	 * It makes sense if either router discovery is off, or if
730 	 * router discover is on and at most one interface is doing RIP.
731 	 */
732 	if (rip_interfaces > 0 && (!rdisc_ok || rip_interfaces > 1)) {
733 		trace_act("turn on RIP");
734 
735 		/* Close all of the query sockets so that we can open
736 		 * the main socket.  SO_REUSEPORT is not a solution,
737 		 * since that would let two daemons bind to the broadcast
738 		 * socket.
739 		 */
740 		for (ifp = ifnet; ifp != 0; ifp = ifp->int_next) {
741 			if (ifp->int_rip_sock >= 0) {
742 				(void)close(ifp->int_rip_sock);
743 				ifp->int_rip_sock = -1;
744 			}
745 		}
746 
747 		rip_sock = get_rip_sock(INADDR_ANY, 1);
748 		rip_sock_mcast = 0;
749 
750 		/* Do not advertise anything until we have heard something
751 		 */
752 		if (next_bcast.tv_sec < now.tv_sec+MIN_WAITTIME)
753 			next_bcast.tv_sec = now.tv_sec+MIN_WAITTIME;
754 
755 		for (ifp = ifnet; ifp != 0; ifp = ifp->int_next) {
756 			ifp->int_query_time = NEVER;
757 			rip_mcast_on(ifp);
758 		}
759 		ifinit_timer.tv_sec = now.tv_sec;
760 
761 	} else if (ifp != 0
762 		   && !(ifp->int_state & IS_REMOTE)
763 		   && ifp->int_rip_sock < 0) {
764 		/* RIP is off, so ensure there are sockets on which
765 		 * to listen for queries.
766 		 */
767 		ifp->int_rip_sock = get_rip_sock(ifp->int_addr, 0);
768 	}
769 
770 	fix_select();
771 }
772 
773 
774 /* die if malloc(3) fails
775  */
776 void *
777 rtmalloc(size_t size,
778 	 const char *msg)
779 {
780 	void *p = malloc(size);
781 	if (p == 0)
782 		logbad(1,"malloc(%ld) failed in %s", (long)size, msg);
783 	return p;
784 }
785 
786 
787 /* get a random instant in an interval
788  */
789 void
790 intvl_random(struct timeval *tp,	/* put value here */
791 	     u_long lo,			/* value is after this second */
792 	     u_long hi)			/* and before this */
793 {
794 	tp->tv_sec = (time_t)(hi == lo
795 			      ? lo
796 			      : (lo + random() % ((hi - lo))));
797 	tp->tv_usec = random() % 1000000;
798 }
799 
800 
801 void
802 timevaladd(struct timeval *t1,
803 	   struct timeval *t2)
804 {
805 
806 	t1->tv_sec += t2->tv_sec;
807 	if ((t1->tv_usec += t2->tv_usec) >= 1000000) {
808 		t1->tv_sec++;
809 		t1->tv_usec -= 1000000;
810 	}
811 }
812 
813 
814 /* t1 = t2 - t3
815  */
816 static void
817 timevalsub(struct timeval *t1,
818 	   struct timeval *t2,
819 	   struct timeval *t3)
820 {
821 	t1->tv_sec = t2->tv_sec - t3->tv_sec;
822 	if ((t1->tv_usec = t2->tv_usec - t3->tv_usec) < 0) {
823 		t1->tv_sec--;
824 		t1->tv_usec += 1000000;
825 	}
826 }
827 
828 
829 /* put a message into the system log
830  */
831 void
832 msglog(const char *p, ...)
833 {
834 	va_list args;
835 
836 	trace_flush();
837 
838 	va_start(args, p);
839 	vsyslog(LOG_ERR, p, args);
840 
841 	if (ftrace != 0) {
842 		if (ftrace == stdout)
843 			(void)fputs("routed: ", ftrace);
844 		(void)vfprintf(ftrace, p, args);
845 		(void)fputc('\n', ftrace);
846 	}
847 }
848 
849 
850 /* Put a message about a bad system into the system log if
851  * we have not complained about it recently.
852  *
853  * It is desirable to complain about all bad systems, but not too often.
854  * In the worst case, it is not practical to keep track of all bad systems.
855  * For example, there can be many systems with the wrong password.
856  */
857 void
858 msglim(struct msg_limit *lim, naddr addr, const char *p, ...)
859 {
860 	va_list args;
861 	int i;
862 	struct msg_sub *ms1, *ms;
863 	const char *p1;
864 
865 	va_start(args, p);
866 
867 	/* look for the oldest slot in the table
868 	 * or the slot for the bad router.
869 	 */
870 	ms = ms1 = lim->subs;
871 	for (i = MSG_SUBJECT_N; ; i--, ms1++) {
872 		if (i == 0) {
873 			/* Reuse a slot at most once every 10 minutes.
874 			 */
875 			if (lim->reuse > now.tv_sec) {
876 				ms = 0;
877 			} else {
878 				ms = ms1;
879 				lim->reuse = now.tv_sec + 10*60;
880 			}
881 			break;
882 		}
883 		if (ms->addr == addr) {
884 			/* Repeat a complaint about a given system at
885 			 * most once an hour.
886 			 */
887 			if (ms->until > now.tv_sec)
888 				ms = 0;
889 			break;
890 		}
891 		if (ms->until < ms1->until)
892 			ms = ms1;
893 	}
894 	if (ms != 0) {
895 		ms->addr = addr;
896 		ms->until = now.tv_sec + 60*60;	/* 60 minutes */
897 
898 		trace_flush();
899 		for (p1 = p; *p1 == ' '; p1++)
900 			continue;
901 		vsyslog(LOG_ERR, p1, args);
902 	}
903 
904 	/* always display the message if tracing */
905 	if (ftrace != 0) {
906 		(void)vfprintf(ftrace, p, args);
907 		(void)fputc('\n', ftrace);
908 	}
909 }
910 
911 
912 void
913 logbad(int dump, const char *p, ...)
914 {
915 	va_list args;
916 
917 	trace_flush();
918 
919 	va_start(args, p);
920 	vsyslog(LOG_ERR, p, args);
921 
922 	(void)fputs("routed: ", stderr);
923 	(void)vfprintf(stderr, p, args);
924 	(void)fputs("; giving up\n",stderr);
925 	(void)fflush(stderr);
926 
927 	if (dump)
928 		abort();
929 	exit(1);
930 }
931