main.c revision 272461 
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: releng/10.1/sbin/routed/main.c 229778 2012-01-07 16:09:33Z uqs $
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: releng/10.1/sbin/routed/main.c 229778 2012-01-07 16:09:33Z uqs $");
49#else
50__RCSID("$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 */
71
72struct timeval epoch;			/* when started */
73struct timeval clk;
74static struct timeval prev_clk;
75static int usec_fudge;
76struct timeval now;			/* current idea of time */
77time_t	now_stale;
78time_t	now_expire;
79time_t	now_garbage;
80
81static struct timeval next_bcast;	/* next general broadcast */
82struct timeval no_flash = {		/* inhibit flash update */
83	EPOCH+SUPPLY_INTERVAL, 0
84};
85
86static struct timeval flush_kern_timer;
87
88static fd_set fdbits;
89static int sock_max;
90int	rip_sock = -1;			/* RIP socket */
91const struct interface *rip_sock_mcast;	/* current multicast interface */
92int	rt_sock;			/* routing socket */
93int	rt_sock_seqno;
94
95
96static  int get_rip_sock(naddr, int);
97static void timevalsub(struct timeval *, struct timeval *, struct timeval *);
98static void sigalrm(int s UNUSED);
99static void sigterm(int sig);
100
101int
102main(int argc,
103     char *argv[])
104{
105	int n, mib[4], off;
106	size_t len;
107	char *p, *q;
108	const char *cp;
109	struct timeval wtime, t2;
110	time_t dt;
111	fd_set ibits;
112	naddr p_net, p_mask;
113	struct interface *ifp;
114	struct parm parm;
115	char *tracename = 0;
116
117
118	/* Some shells are badly broken and send SIGHUP to backgrounded
119	 * processes.
120	 */
121	signal(SIGHUP, SIG_IGN);
122
123	openlog("routed", LOG_PID, LOG_DAEMON);
124	ftrace = stdout;
125
126	gettimeofday(&clk, 0);
127	prev_clk = clk;
128	epoch = clk;
129	epoch.tv_sec -= EPOCH;
130	now.tv_sec = EPOCH;
131	now_stale = EPOCH - STALE_TIME;
132	now_expire = EPOCH - EXPIRE_TIME;
133	now_garbage = EPOCH - GARBAGE_TIME;
134	wtime.tv_sec = 0;
135
136	(void)gethostname(myname, sizeof(myname)-1);
137	(void)gethost(myname, &myaddr);
138
139	while ((n = getopt(argc, argv, "sqdghmAtvT:F:P:")) != -1) {
140		switch (n) {
141		case 's':
142			supplier = 1;
143			supplier_set = 1;
144			break;
145
146		case 'q':
147			supplier = 0;
148			supplier_set = 1;
149			break;
150
151		case 'd':
152			background = 0;
153			break;
154
155		case 'g':
156			memset(&parm, 0, sizeof(parm));
157			parm.parm_d_metric = 1;
158			cp = check_parms(&parm);
159			if (cp != 0)
160				msglog("bad -g: %s", cp);
161			else
162				default_gateway = 1;
163			break;
164
165		case 'h':		/* suppress extra host routes */
166			ridhosts = 1;
167			break;
168
169		case 'm':		/* advertise host route */
170			mhome = 1;	/* on multi-homed hosts */
171			break;
172
173		case 'A':
174			/* Ignore authentication if we do not care.
175			 * Crazy as it is, that is what RFC 1723 requires.
176			 */
177			auth_ok = 0;
178			break;
179
180		case 't':
181			new_tracelevel++;
182			break;
183
184		case 'T':
185			tracename = optarg;
186			break;
187
188		case 'F':		/* minimal routes for SLIP */
189			n = FAKE_METRIC;
190			p = strchr(optarg,',');
191			if (p && *p != '\0') {
192				n = (int)strtoul(p+1, &q, 0);
193				if (*q == '\0'
194				    && n <= HOPCNT_INFINITY-1
195				    && n >= 1)
196					*p = '\0';
197			}
198			if (!getnet(optarg, &p_net, &p_mask)) {
199				msglog("bad network; \"-F %s\"",
200				       optarg);
201				break;
202			}
203			memset(&parm, 0, sizeof(parm));
204			parm.parm_net = p_net;
205			parm.parm_mask = p_mask;
206			parm.parm_d_metric = n;
207			cp = check_parms(&parm);
208			if (cp != 0)
209				msglog("bad -F: %s", cp);
210			break;
211
212		case 'P':
213			/* handle arbitrary parameters.
214			 */
215			q = strdup(optarg);
216			cp = parse_parms(q, 0);
217			if (cp != 0)
218				msglog("%s in \"-P %s\"", cp, optarg);
219			free(q);
220			break;
221
222		case 'v':
223			/* display version */
224			verbose++;
225			msglog("version 2.31");
226			break;
227
228		default:
229			goto usage;
230		}
231	}
232	argc -= optind;
233	argv += optind;
234
235	if (tracename == 0 && argc >= 1) {
236		tracename = *argv++;
237		argc--;
238	}
239	if (tracename != 0 && tracename[0] == '\0')
240		goto usage;
241	if (argc != 0) {
242usage:
243		logbad(0, "usage: routed [-sqdghmAtv] [-T tracefile]"
244		       " [-F net[,metric]] [-P parms]");
245	}
246	if (geteuid() != 0) {
247		if (verbose)
248			exit(0);
249		logbad(0, "requires UID 0");
250	}
251
252	mib[0] = CTL_NET;
253	mib[1] = PF_INET;
254	mib[2] = IPPROTO_IP;
255	mib[3] = IPCTL_FORWARDING;
256	len = sizeof(ipforwarding);
257	if (sysctl(mib, 4, &ipforwarding, &len, 0, 0) < 0)
258		LOGERR("sysctl(IPCTL_FORWARDING)");
259
260	if (!ipforwarding) {
261		if (supplier)
262			msglog("-s incompatible with ipforwarding=0");
263		if (default_gateway) {
264			msglog("-g incompatible with ipforwarding=0");
265			default_gateway = 0;
266		}
267		supplier = 0;
268		supplier_set = 1;
269	}
270	if (default_gateway) {
271		if (supplier_set && !supplier) {
272			msglog("-g and -q incompatible");
273		} else {
274			supplier = 1;
275			supplier_set = 1;
276		}
277	}
278
279
280	signal(SIGALRM, sigalrm);
281	if (!background)
282		signal(SIGHUP, sigterm);    /* SIGHUP fatal during debugging */
283	signal(SIGTERM, sigterm);
284	signal(SIGINT, sigterm);
285	signal(SIGUSR1, sigtrace_on);
286	signal(SIGUSR2, sigtrace_off);
287
288	/* get into the background */
289#ifdef sgi
290	if (0 > _daemonize(background ? 0 : (_DF_NOCHDIR|_DF_NOFORK),
291			   STDIN_FILENO, STDOUT_FILENO, STDERR_FILENO))
292		BADERR(0, "_daemonize()");
293#else
294	if (background && daemon(0, 1) < 0)
295		BADERR(0,"daemon()");
296#endif
297
298#if defined(__NetBSD__)
299	pidfile(0);
300#endif
301	mypid = getpid();
302#ifdef __FreeBSD__
303	srandomdev();
304#else
305	srandom((int)(clk.tv_sec ^ clk.tv_usec ^ mypid));
306#endif
307
308	/* prepare socket connected to the kernel.
309	 */
310	rt_sock = socket(AF_ROUTE, SOCK_RAW, 0);
311	if (rt_sock < 0)
312		BADERR(1,"rt_sock = socket()");
313	if (fcntl(rt_sock, F_SETFL, O_NONBLOCK) == -1)
314		logbad(1, "fcntl(rt_sock) O_NONBLOCK: %s", strerror(errno));
315	off = 0;
316	if (setsockopt(rt_sock, SOL_SOCKET,SO_USELOOPBACK,
317		       &off,sizeof(off)) < 0)
318		LOGERR("setsockopt(SO_USELOOPBACK,0)");
319
320	fix_select();
321
322
323	if (tracename != 0) {
324		strncpy(inittracename, tracename, sizeof(inittracename)-1);
325		set_tracefile(inittracename, "%s", -1);
326	} else {
327		tracelevel_msg("%s", -1);   /* turn on tracing to stdio */
328	}
329
330	bufinit();
331
332	/* initialize radix tree */
333	rtinit();
334
335	/* Pick a random part of the second for our output to minimize
336	 * collisions.
337	 *
338	 * Start broadcasting after hearing from other routers, and
339	 * at a random time so a bunch of systems do not get synchronized
340	 * after a power failure.
341	 */
342	intvl_random(&next_bcast, EPOCH+MIN_WAITTIME, EPOCH+SUPPLY_INTERVAL);
343	age_timer.tv_usec = next_bcast.tv_usec;
344	age_timer.tv_sec = EPOCH+MIN_WAITTIME;
345	rdisc_timer = next_bcast;
346	ifinit_timer.tv_usec = next_bcast.tv_usec;
347
348	/* Collect an initial view of the world by checking the interface
349	 * configuration and the kludge file.
350	 */
351	gwkludge();
352	ifinit();
353
354	/* Ask for routes */
355	rip_query();
356	rdisc_sol();
357
358	/* Now turn off stdio if not tracing */
359	if (new_tracelevel == 0)
360		trace_close(background);
361
362	/* Loop forever, listening and broadcasting.
363	 */
364	for (;;) {
365		prev_clk = clk;
366		gettimeofday(&clk, 0);
367		if (prev_clk.tv_sec == clk.tv_sec
368		    && prev_clk.tv_usec == clk.tv_usec+usec_fudge) {
369			/* Much of `routed` depends on time always advancing.
370			 * On systems that do not guarantee that gettimeofday()
371			 * produces unique timestamps even if called within
372			 * a single tick, use trickery like that in classic
373			 * BSD kernels.
374			 */
375			clk.tv_usec += ++usec_fudge;
376
377		} else {
378			usec_fudge = 0;
379
380			timevalsub(&t2, &clk, &prev_clk);
381			if (t2.tv_sec < 0
382			    || t2.tv_sec > wtime.tv_sec + 5) {
383				/* Deal with time changes before other
384				 * housekeeping to keep everything straight.
385				 */
386				dt = t2.tv_sec;
387				if (dt > 0)
388					dt -= wtime.tv_sec;
389				trace_act("time changed by %d sec", (int)dt);
390				epoch.tv_sec += dt;
391			}
392		}
393		timevalsub(&now, &clk, &epoch);
394		now_stale = now.tv_sec - STALE_TIME;
395		now_expire = now.tv_sec - EXPIRE_TIME;
396		now_garbage = now.tv_sec - GARBAGE_TIME;
397
398		/* deal with signals that should affect tracing */
399		set_tracelevel();
400
401		if (stopint != 0) {
402			rip_bcast(0);
403			rdisc_adv();
404			trace_off("exiting with signal %d", stopint);
405			exit(stopint | 128);
406		}
407
408		/* look for new or dead interfaces */
409		timevalsub(&wtime, &ifinit_timer, &now);
410		if (wtime.tv_sec <= 0) {
411			wtime.tv_sec = 0;
412			ifinit();
413			rip_query();
414			continue;
415		}
416
417		/* Check the kernel table occasionally for mysteriously
418		 * evaporated routes
419		 */
420		timevalsub(&t2, &flush_kern_timer, &now);
421		if (t2.tv_sec <= 0) {
422			flush_kern();
423			flush_kern_timer.tv_sec = (now.tv_sec
424						   + CHECK_QUIET_INTERVAL);
425			continue;
426		}
427		if (timercmp(&t2, &wtime, <))
428			wtime = t2;
429
430		/* If it is time, then broadcast our routes.
431		 */
432		if (supplier || advertise_mhome) {
433			timevalsub(&t2, &next_bcast, &now);
434			if (t2.tv_sec <= 0) {
435				/* Synchronize the aging and broadcast
436				 * timers to minimize awakenings
437				 */
438				age(0);
439
440				rip_bcast(0);
441
442				/* It is desirable to send routing updates
443				 * regularly.  So schedule the next update
444				 * 30 seconds after the previous one was
445				 * scheduled, instead of 30 seconds after
446				 * the previous update was finished.
447				 * Even if we just started after discovering
448				 * a 2nd interface or were otherwise delayed,
449				 * pick a 30-second anniversary of the
450				 * original broadcast time.
451				 */
452				n = 1 + (0-t2.tv_sec)/SUPPLY_INTERVAL;
453				next_bcast.tv_sec += n*SUPPLY_INTERVAL;
454
455				continue;
456			}
457
458			if (timercmp(&t2, &wtime, <))
459				wtime = t2;
460		}
461
462		/* If we need a flash update, either do it now or
463		 * set the delay to end when it is time.
464		 *
465		 * If we are within MIN_WAITTIME seconds of a full update,
466		 * do not bother.
467		 */
468		if (need_flash
469		    && supplier
470		    && no_flash.tv_sec+MIN_WAITTIME < next_bcast.tv_sec) {
471			/* accurate to the millisecond */
472			if (!timercmp(&no_flash, &now, >))
473				rip_bcast(1);
474			timevalsub(&t2, &no_flash, &now);
475			if (timercmp(&t2, &wtime, <))
476				wtime = t2;
477		}
478
479		/* trigger the main aging timer.
480		 */
481		timevalsub(&t2, &age_timer, &now);
482		if (t2.tv_sec <= 0) {
483			age(0);
484			continue;
485		}
486		if (timercmp(&t2, &wtime, <))
487			wtime = t2;
488
489		/* update the kernel routing table
490		 */
491		timevalsub(&t2, &need_kern, &now);
492		if (t2.tv_sec <= 0) {
493			age(0);
494			continue;
495		}
496		if (timercmp(&t2, &wtime, <))
497			wtime = t2;
498
499		/* take care of router discovery,
500		 * but do it in the correct the millisecond
501		 */
502		if (!timercmp(&rdisc_timer, &now, >)) {
503			rdisc_age(0);
504			continue;
505		}
506		timevalsub(&t2, &rdisc_timer, &now);
507		if (timercmp(&t2, &wtime, <))
508			wtime = t2;
509
510
511		/* wait for input or a timer to expire.
512		 */
513		trace_flush();
514		ibits = fdbits;
515		n = select(sock_max, &ibits, 0, 0, &wtime);
516		if (n <= 0) {
517			if (n < 0 && errno != EINTR && errno != EAGAIN)
518				BADERR(1,"select");
519			continue;
520		}
521
522		if (FD_ISSET(rt_sock, &ibits)) {
523			read_rt();
524			n--;
525		}
526		if (rdisc_sock >= 0 && FD_ISSET(rdisc_sock, &ibits)) {
527			read_d();
528			n--;
529		}
530		if (rip_sock >= 0 && FD_ISSET(rip_sock, &ibits)) {
531			read_rip(rip_sock, 0);
532			n--;
533		}
534
535		LIST_FOREACH(ifp, &ifnet, int_list) {
536			if (n <= 0)
537				break;
538			if (ifp->int_rip_sock >= 0
539			    && FD_ISSET(ifp->int_rip_sock, &ibits)) {
540				read_rip(ifp->int_rip_sock, ifp);
541				n--;
542			}
543		}
544	}
545}
546
547
548/* ARGSUSED */
549static void
550sigalrm(int s UNUSED)
551{
552	/* Historically, SIGALRM would cause the daemon to check for
553	 * new and broken interfaces.
554	 */
555	ifinit_timer.tv_sec = now.tv_sec;
556	trace_act("SIGALRM");
557}
558
559
560/* watch for fatal signals */
561static void
562sigterm(int sig)
563{
564	stopint = sig;
565	(void)signal(sig, SIG_DFL);	/* catch it only once */
566}
567
568
569void
570fix_select(void)
571{
572	struct interface *ifp;
573
574
575	FD_ZERO(&fdbits);
576	sock_max = 0;
577
578	FD_SET(rt_sock, &fdbits);
579	if (sock_max <= rt_sock)
580		sock_max = rt_sock+1;
581	if (rip_sock >= 0) {
582		FD_SET(rip_sock, &fdbits);
583		if (sock_max <= rip_sock)
584			sock_max = rip_sock+1;
585	}
586	LIST_FOREACH(ifp, &ifnet, int_list) {
587		if (ifp->int_rip_sock >= 0) {
588			FD_SET(ifp->int_rip_sock, &fdbits);
589			if (sock_max <= ifp->int_rip_sock)
590				sock_max = ifp->int_rip_sock+1;
591		}
592	}
593	if (rdisc_sock >= 0) {
594		FD_SET(rdisc_sock, &fdbits);
595		if (sock_max <= rdisc_sock)
596			sock_max = rdisc_sock+1;
597	}
598}
599
600
601void
602fix_sock(int sock,
603	 const char *name)
604{
605	int on;
606#define MIN_SOCKBUF (4*1024)
607	static int rbuf;
608
609	if (fcntl(sock, F_SETFL, O_NONBLOCK) == -1)
610		logbad(1, "fcntl(%s) O_NONBLOCK: %s",
611		       name, strerror(errno));
612	on = 1;
613	if (setsockopt(sock, SOL_SOCKET,SO_BROADCAST, &on,sizeof(on)) < 0)
614		msglog("setsockopt(%s,SO_BROADCAST): %s",
615		       name, strerror(errno));
616#ifdef USE_PASSIFNAME
617	on = 1;
618	if (setsockopt(sock, SOL_SOCKET, SO_PASSIFNAME, &on,sizeof(on)) < 0)
619		msglog("setsockopt(%s,SO_PASSIFNAME): %s",
620		       name, strerror(errno));
621#endif
622
623	if (rbuf >= MIN_SOCKBUF) {
624		if (setsockopt(sock, SOL_SOCKET, SO_RCVBUF,
625			       &rbuf, sizeof(rbuf)) < 0)
626			msglog("setsockopt(%s,SO_RCVBUF=%d): %s",
627			       name, rbuf, strerror(errno));
628	} else {
629		for (rbuf = 60*1024; ; rbuf -= 4096) {
630			if (setsockopt(sock, SOL_SOCKET, SO_RCVBUF,
631				       &rbuf, sizeof(rbuf)) == 0) {
632				trace_act("RCVBUF=%d", rbuf);
633				break;
634			}
635			if (rbuf < MIN_SOCKBUF) {
636				msglog("setsockopt(%s,SO_RCVBUF = %d): %s",
637				       name, rbuf, strerror(errno));
638				break;
639			}
640		}
641	}
642}
643
644
645/* get a rip socket
646 */
647static int				/* <0 or file descriptor */
648get_rip_sock(naddr addr,
649	     int serious)		/* 1=failure to bind is serious */
650{
651	struct sockaddr_in rsin;
652	unsigned char ttl;
653	int s;
654
655
656	if ((s = socket(AF_INET, SOCK_DGRAM, 0)) < 0)
657		BADERR(1,"rip_sock = socket()");
658
659	memset(&rsin, 0, sizeof(rsin));
660#ifdef _HAVE_SIN_LEN
661	rsin.sin_len = sizeof(rsin);
662#endif
663	rsin.sin_family = AF_INET;
664	rsin.sin_port = htons(RIP_PORT);
665	rsin.sin_addr.s_addr = addr;
666	if (bind(s, (struct sockaddr *)&rsin, sizeof(rsin)) < 0) {
667		if (serious)
668			BADERR(errno != EADDRINUSE, "bind(rip_sock)");
669		return -1;
670	}
671	fix_sock(s,"rip_sock");
672
673	ttl = 1;
674	if (setsockopt(s, IPPROTO_IP, IP_MULTICAST_TTL,
675		       &ttl, sizeof(ttl)) < 0)
676		DBGERR(1,"rip_sock setsockopt(IP_MULTICAST_TTL)");
677
678	return s;
679}
680
681
682/* turn off main RIP socket */
683void
684rip_off(void)
685{
686	struct interface *ifp;
687	naddr addr;
688
689
690	if (rip_sock >= 0 && !mhome) {
691		trace_act("turn off RIP");
692
693		(void)close(rip_sock);
694		rip_sock = -1;
695
696		/* get non-broadcast sockets to listen to queries.
697		 */
698		LIST_FOREACH(ifp, &ifnet, int_list) {
699			if (ifp->int_state & IS_REMOTE)
700				continue;
701			if (ifp->int_rip_sock < 0) {
702				addr = ((ifp->int_if_flags & IFF_POINTOPOINT)
703					? ifp->int_dstaddr
704					: ifp->int_addr);
705				ifp->int_rip_sock = get_rip_sock(addr, 0);
706			}
707		}
708
709		fix_select();
710
711		age(0);
712	}
713}
714
715
716/* turn on RIP multicast input via an interface
717 */
718static void
719rip_mcast_on(struct interface *ifp)
720{
721	struct group_req gr;
722	struct sockaddr_in *sin;
723
724	if (!IS_RIP_IN_OFF(ifp->int_state)
725	    && (ifp->int_if_flags & IFF_MULTICAST)
726	    && !(ifp->int_state & IS_ALIAS)) {
727		memset(&gr, 0, sizeof(gr));
728		gr.gr_interface = ifp->int_index;
729		sin = (struct sockaddr_in *)&gr.gr_group;
730		sin->sin_family = AF_INET;
731#ifdef _HAVE_SIN_LEN
732		sin->sin_len = sizeof(struct sockaddr_in);
733#endif
734		sin->sin_addr.s_addr = htonl(INADDR_RIP_GROUP);
735		if (setsockopt(rip_sock, IPPROTO_IP, MCAST_JOIN_GROUP,
736			       &gr, sizeof(gr)) < 0)
737			LOGERR("setsockopt(MCAST_JOIN_GROUP RIP)");
738	}
739}
740
741
742/* Prepare socket used for RIP.
743 */
744void
745rip_on(struct interface *ifp)
746{
747	/* If the main RIP socket is already alive, only start receiving
748	 * multicasts for this interface.
749	 */
750	if (rip_sock >= 0) {
751		if (ifp != 0)
752			rip_mcast_on(ifp);
753		return;
754	}
755
756	/* If the main RIP socket is off and it makes sense to turn it on,
757	 * then turn it on for all of the interfaces.
758	 * It makes sense if either router discovery is off, or if
759	 * router discover is on and at most one interface is doing RIP.
760	 */
761	if (rip_interfaces > 0 && (!rdisc_ok || rip_interfaces > 1)) {
762		trace_act("turn on RIP");
763
764		/* Close all of the query sockets so that we can open
765		 * the main socket.  SO_REUSEPORT is not a solution,
766		 * since that would let two daemons bind to the broadcast
767		 * socket.
768		 */
769		LIST_FOREACH(ifp, &ifnet, int_list) {
770			if (ifp->int_rip_sock >= 0) {
771				(void)close(ifp->int_rip_sock);
772				ifp->int_rip_sock = -1;
773			}
774		}
775
776		rip_sock = get_rip_sock(INADDR_ANY, 1);
777		rip_sock_mcast = 0;
778
779		/* Do not advertise anything until we have heard something
780		 */
781		if (next_bcast.tv_sec < now.tv_sec+MIN_WAITTIME)
782			next_bcast.tv_sec = now.tv_sec+MIN_WAITTIME;
783
784		LIST_FOREACH(ifp, &ifnet, int_list) {
785			ifp->int_query_time = NEVER;
786			rip_mcast_on(ifp);
787		}
788		ifinit_timer.tv_sec = now.tv_sec;
789
790	} else if (ifp != 0
791		   && !(ifp->int_state & IS_REMOTE)
792		   && ifp->int_rip_sock < 0) {
793		/* RIP is off, so ensure there are sockets on which
794		 * to listen for queries.
795		 */
796		ifp->int_rip_sock = get_rip_sock(ifp->int_addr, 0);
797	}
798
799	fix_select();
800}
801
802
803/* die if malloc(3) fails
804 */
805void *
806rtmalloc(size_t size,
807	 const char *msg)
808{
809	void *p = malloc(size);
810	if (p == 0)
811		logbad(1,"malloc(%lu) failed in %s", (u_long)size, msg);
812	return p;
813}
814
815
816/* get a random instant in an interval
817 */
818void
819intvl_random(struct timeval *tp,	/* put value here */
820	     u_long lo,			/* value is after this second */
821	     u_long hi)			/* and before this */
822{
823	tp->tv_sec = (time_t)(hi == lo
824			      ? lo
825			      : (lo + random() % ((hi - lo))));
826	tp->tv_usec = random() % 1000000;
827}
828
829
830void
831timevaladd(struct timeval *t1,
832	   struct timeval *t2)
833{
834
835	t1->tv_sec += t2->tv_sec;
836	if ((t1->tv_usec += t2->tv_usec) >= 1000000) {
837		t1->tv_sec++;
838		t1->tv_usec -= 1000000;
839	}
840}
841
842
843/* t1 = t2 - t3
844 */
845static void
846timevalsub(struct timeval *t1,
847	   struct timeval *t2,
848	   struct timeval *t3)
849{
850	t1->tv_sec = t2->tv_sec - t3->tv_sec;
851	if ((t1->tv_usec = t2->tv_usec - t3->tv_usec) < 0) {
852		t1->tv_sec--;
853		t1->tv_usec += 1000000;
854	}
855}
856
857
858/* put a message into the system log
859 */
860void
861msglog(const char *p, ...)
862{
863	va_list args;
864
865	trace_flush();
866
867	va_start(args, p);
868	vsyslog(LOG_ERR, p, args);
869	va_end(args);
870	if (ftrace != 0) {
871		if (ftrace == stdout)
872			(void)fputs("routed: ", ftrace);
873		va_start(args, p);
874		(void)vfprintf(ftrace, p, args);
875		va_end(args);
876		(void)fputc('\n', ftrace);
877	}
878}
879
880
881/* Put a message about a bad system into the system log if
882 * we have not complained about it recently.
883 *
884 * It is desirable to complain about all bad systems, but not too often.
885 * In the worst case, it is not practical to keep track of all bad systems.
886 * For example, there can be many systems with the wrong password.
887 */
888void
889msglim(struct msg_limit *lim, naddr addr, const char *p, ...)
890{
891	va_list args;
892	int i;
893	struct msg_sub *ms1, *ms;
894	const char *p1;
895
896	/* look for the oldest slot in the table
897	 * or the slot for the bad router.
898	 */
899	ms = ms1 = lim->subs;
900	for (i = MSG_SUBJECT_N; ; i--, ms1++) {
901		if (i == 0) {
902			/* Reuse a slot at most once every 10 minutes.
903			 */
904			if (lim->reuse > now.tv_sec) {
905				ms = 0;
906			} else {
907				ms = ms1;
908				lim->reuse = now.tv_sec + 10*60;
909			}
910			break;
911		}
912		if (ms->addr == addr) {
913			/* Repeat a complaint about a given system at
914			 * most once an hour.
915			 */
916			if (ms->until > now.tv_sec)
917				ms = 0;
918			break;
919		}
920		if (ms->until < ms1->until)
921			ms = ms1;
922	}
923	if (ms != 0) {
924		ms->addr = addr;
925		ms->until = now.tv_sec + 60*60;	/* 60 minutes */
926
927		trace_flush();
928		for (p1 = p; *p1 == ' '; p1++)
929			continue;
930		va_start(args, p);
931		vsyslog(LOG_ERR, p1, args);
932		va_end(args);
933	}
934
935	/* always display the message if tracing */
936	if (ftrace != 0) {
937		va_start(args, p);
938		(void)vfprintf(ftrace, p, args);
939		va_end(args);
940		(void)fputc('\n', ftrace);
941	}
942}
943
944
945void
946logbad(int dump, const char *p, ...)
947{
948	va_list args;
949
950	trace_flush();
951
952	va_start(args, p);
953	vsyslog(LOG_ERR, p, args);
954	va_end(args);
955	(void)fputs("routed: ", stderr);
956	va_start(args, p);
957	(void)vfprintf(stderr, p, args);
958	va_end(args);
959	(void)fputs("; giving up\n",stderr);
960	(void)fflush(stderr);
961
962	if (dump)
963		abort();
964	exit(1);
965}
966