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main.c revision 1.14 
      1 /*	$NetBSD: main.c,v 1.14 1996/08/10 01:29:23 thorpej 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 acknowledgement:
     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 char copyright[] =
     37 "@(#) Copyright (c) 1983, 1988, 1993\n\
     38 	The Regents of the University of California.  All rights reserved.\n";
     39 #if !defined(lint) && !defined(sgi)
     40 #if 0
     41 static char sccsid[] = "@(#)main.c	8.1 (Berkeley) 6/5/93";
     42 #else
     43 static char rcsid[] = "$NetBSD: main.c,v 1.14 1996/08/10 01:29:23 thorpej Exp $";
     44 #endif
     45 #endif /* not lint */
     46 
     47 #include "defs.h"
     48 #include "pathnames.h"
     49 #ifdef sgi
     50 #include "math.h"
     51 #endif
     52 #include <signal.h>
     53 #include <fcntl.h>
     54 #include <sys/file.h>
     55 
     56 pid_t	mypid;
     57 
     58 naddr	myaddr;				/* system address */
     59 char	myname[MAXHOSTNAMELEN+1];
     60 
     61 int	supplier;			/* supply or broadcast updates */
     62 int	supplier_set;
     63 int	ipforwarding = 1;		/* kernel forwarding on */
     64 
     65 int	default_gateway;		/* 1=advertise default */
     66 int	background = 1;
     67 int	ridhosts;			/* 1=reduce host routes */
     68 int	mhome;				/* 1=want multi-homed host route */
     69 int	advertise_mhome;		/* 1=must continue adverising it */
     70 int	auth_ok = 1;			/* 1=ignore auth if we do not care */
     71 
     72 struct timeval epoch;			/* when started */
     73 struct timeval clk, prev_clk;
     74 struct timeval now;			/* current idea of time */
     75 time_t	now_stale;
     76 time_t	now_garbage;
     77 
     78 struct timeval next_bcast;		/* next general broadcast */
     79 struct timeval no_flash = {EPOCH+SUPPLY_INTERVAL};  /* inhibit flash update */
     80 
     81 fd_set	fdbits;
     82 int	sock_max;
     83 int	rip_sock = -1;			/* RIP socket */
     84 struct interface *rip_sock_mcast;	/* current multicast interface */
     85 int	rt_sock;			/* routing socket */
     86 int	rt_sock_seqno;
     87 
     88 
     89 static  int get_rip_sock(naddr, int);
     90 static void timevalsub(struct timeval *, struct timeval *, struct timeval *);
     91 
     92 int
     93 main(int argc,
     94      char *argv[])
     95 {
     96 	int n, mib[4], off;
     97 	size_t len;
     98 	char *p, *q;
     99 	struct timeval wtime, t2;
    100 	time_t dt;
    101 	fd_set ibits;
    102 	naddr p_addr, p_mask;
    103 	struct interface *ifp;
    104 	struct parm parm;
    105 	char *tracename = 0;
    106 
    107 
    108 	openlog("routed", LOG_PID | LOG_ODELAY, LOG_DAEMON);
    109 	ftrace = stdout;
    110 
    111 	gettimeofday(&clk, 0);
    112 	prev_clk = clk;
    113 	epoch = clk;
    114 	epoch.tv_sec -= EPOCH;
    115 	now.tv_sec = EPOCH;
    116 	now_stale = EPOCH - STALE_TIME;
    117 	now_garbage = EPOCH - GARBAGE_TIME;
    118 	wtime.tv_sec = 0;
    119 
    120 	(void)gethostname(myname, sizeof(myname)-1);
    121 	(void)gethost(myname, &myaddr);
    122 
    123 	while ((n = getopt(argc, argv, "sqdghmpAtT:F:P:")) != EOF) {
    124 		switch (n) {
    125 		case 's':
    126 			supplier = 1;
    127 			supplier_set = 1;
    128 			break;
    129 
    130 		case 'q':
    131 			supplier = 0;
    132 			supplier_set = 1;
    133 			break;
    134 
    135 		case 'd':
    136 			background = 0;
    137 			break;
    138 
    139 		case 'g':
    140 			bzero(&parm, sizeof(parm));
    141 			parm.parm_d_metric = 1;
    142 			p = check_parms(&parm);
    143 			if (p != 0)
    144 				msglog("bad -g: %s", p);
    145 			else
    146 				default_gateway = 1;
    147 			break;
    148 
    149 		case 'h':		/* suppress extra host routes */
    150 			ridhosts = 1;
    151 			break;
    152 
    153 		case 'm':		/* advertise host route */
    154 			mhome = 1;	/* on multi-homed hosts */
    155 			break;
    156 
    157 		case 'A':
    158 			/* Ignore authentication if we do not care.
    159 			 * Crazy as it is, that is what RFC 1723 requires.
    160 			 */
    161 			auth_ok = 0;
    162 			break;
    163 
    164 		case 't':
    165 			new_tracelevel++;
    166 			break;
    167 
    168 		case 'T':
    169 			tracename = optarg;
    170 			break;
    171 
    172 		case 'F':		/* minimal routes for SLIP */
    173 			n = HOPCNT_INFINITY-2;
    174 			p = strchr(optarg,',');
    175 			if (p && *p != '\0') {
    176 				n = (int)strtoul(p+1, &q, 0);
    177 				if (*q == '\0'
    178 				    && n <= HOPCNT_INFINITY-1
    179 				    && n >= 1)
    180 					*p = '\0';
    181 			}
    182 			if (!getnet(optarg, &p_addr, &p_mask)) {
    183 				msglog("bad network; \"-F %s\"",
    184 				       optarg);
    185 				break;
    186 			}
    187 			bzero(&parm, sizeof(parm));
    188 			parm.parm_addr_h = ntohl(p_addr);
    189 			parm.parm_mask = p_mask;
    190 			parm.parm_d_metric = n;
    191 			p = check_parms(&parm);
    192 			if (p != 0)
    193 				msglog("bad -F: %s", p);
    194 			break;
    195 
    196 		case 'P':
    197 			/* handle arbirary, (usually) per-interface
    198 			 * parameters.
    199 			 */
    200 			p = parse_parms(optarg);
    201 			if (p != 0)
    202 				msglog("bad \"%s\" in \"%s\"",
    203 				       p, optarg);
    204 			break;
    205 
    206 		default:
    207 			goto usage;
    208 		}
    209 	}
    210 	argc -= optind;
    211 	argv += optind;
    212 
    213 	if (tracename == 0 && argc >= 1) {
    214 		tracename = *argv++;
    215 		argc--;
    216 	}
    217 	if (argc != 0) {
    218 usage:
    219 		logbad(0, "usage: routed [-sqdghmpAt] [-T /tracefile]"
    220 		       " [-F net[,metric]] [-P parms]");
    221 	}
    222 	if (geteuid() != 0)
    223 		logbad(0, "requires UID 0");
    224 
    225 	mib[0] = CTL_NET;
    226 	mib[1] = PF_INET;
    227 	mib[2] = IPPROTO_IP;
    228 	mib[3] = IPCTL_FORWARDING;
    229 	len = sizeof(ipforwarding);
    230 	if (sysctl(mib, 4, &ipforwarding, &len, 0, 0) < 0)
    231 		LOGERR("sysctl(IPCTL_FORWARDING)");
    232 
    233 	if (!ipforwarding) {
    234 		if (supplier)
    235 			msglog("-s incompatible with ipforwarding=0");
    236 		if (default_gateway) {
    237 			msglog("-g incompatible with ipforwarding=0");
    238 			default_gateway = 0;
    239 		}
    240 		supplier = 0;
    241 		supplier_set = 1;
    242 	}
    243 	if (default_gateway) {
    244 		if (supplier_set && !supplier) {
    245 			msglog("-g and -q incompatible");
    246 		} else {
    247 			supplier = 1;
    248 			supplier_set = 1;
    249 		}
    250 	}
    251 
    252 
    253 	/* get into the background */
    254 	if (background) {
    255 #ifdef sgi
    256 		if (0 > _daemonize(_DF_NOCHDIR,
    257 				   new_tracelevel == 0 ? -1 : STDOUT_FILENO,
    258 				   new_tracelevel == 0 ? -1 : STDERR_FILENO,
    259 				   -1))
    260 			BADERR(0, "_daemonize()");
    261 #else
    262 		if (daemon(1, 1) < 0)
    263 			BADERR(0,"daemon()");
    264 #endif
    265 	}
    266 
    267 	mypid = getpid();
    268 	srandom((int)(clk.tv_sec ^ clk.tv_usec ^ mypid));
    269 
    270 	/* prepare socket connected to the kernel.
    271 	 */
    272 	rt_sock = socket(AF_ROUTE, SOCK_RAW, 0);
    273 	if (rt_sock < 0)
    274 		BADERR(1,"rt_sock = socket()");
    275 	if (fcntl(rt_sock, F_SETFL, O_NONBLOCK) == -1)
    276 		logbad(1, "fcntl(rt_sock) O_NONBLOCK: %s", strerror(errno));
    277 	off = 0;
    278 	if (setsockopt(rt_sock, SOL_SOCKET,SO_USELOOPBACK,
    279 		       &off,sizeof(off)) < 0)
    280 		LOGERR("setsockopt(SO_USELOOPBACK,0)");
    281 
    282 	/* prepare Router Discovery socket.
    283 	 */
    284 	rdisc_sock = socket(AF_INET, SOCK_RAW, IPPROTO_ICMP);
    285 	if (rdisc_sock < 0)
    286 		BADERR(1,"rdisc_sock = socket()");
    287 	fix_sock(rdisc_sock,"rdisc_sock");
    288 
    289 	fix_select();
    290 
    291 
    292 	if (background && new_tracelevel == 0)
    293 		ftrace = 0;
    294 	if (tracename != 0) {
    295 		trace_on(tracename, 1);
    296 		if (new_tracelevel == 0)	/* use stdout if file is bad */
    297 			new_tracelevel = 1;
    298 	}
    299 	set_tracelevel();
    300 
    301 	/* initialize radix tree */
    302 	rtinit();
    303 
    304 	/* Pick a random part of the second for our output to minimize
    305 	 * collisions.
    306 	 *
    307 	 * Start broadcasting after hearing from other routers, and
    308 	 * at a random time so a bunch of systems do not get synchronized
    309 	 * after a power failure.
    310 	 */
    311 	intvl_random(&next_bcast, EPOCH+MIN_WAITTIME, EPOCH+SUPPLY_INTERVAL);
    312 	age_timer.tv_usec = next_bcast.tv_usec;
    313 	age_timer.tv_sec = EPOCH+MIN_WAITTIME;
    314 	rdisc_timer = next_bcast;
    315 	ifinit_timer.tv_usec = next_bcast.tv_usec;
    316 
    317 	signal(SIGALRM, sigalrm);
    318 	signal(SIGHUP, sigterm);
    319 	signal(SIGTERM, sigterm);
    320 	signal(SIGINT, sigterm);
    321 	signal(SIGUSR1, sigtrace_on);
    322 	signal(SIGUSR2, sigtrace_off);
    323 
    324 	/* Collect an initial view of the world by checking the interface
    325 	 * configuration and the kludge file.
    326 	 */
    327 	gwkludge();
    328 	ifinit();
    329 	flush_kern();
    330 
    331 	/* Ask for routes */
    332 	rip_query();
    333 	if (!supplier)
    334 		rdisc_sol();
    335 
    336 	/* Loop forever, listening and broadcasting.
    337 	 */
    338 	for (;;) {
    339 		prev_clk = clk;
    340 		gettimeofday(&clk, 0);
    341 		timevalsub(&t2, &clk, &prev_clk);
    342 		if (t2.tv_sec < 0
    343 		    || t2.tv_sec > wtime.tv_sec + 5) {
    344 			/* Deal with time changes before other housekeeping to
    345 			 * keep everything straight.
    346 			 */
    347 			dt = t2.tv_sec;
    348 			if (dt > 0)
    349 				dt -= wtime.tv_sec;
    350 			trace_act("time changed by %d sec\n", dt);
    351 			epoch.tv_sec += dt;
    352 		}
    353 		timevalsub(&now, &clk, &epoch);
    354 		now_stale = now.tv_sec - STALE_TIME;
    355 		now_garbage = now.tv_sec - GARBAGE_TIME;
    356 
    357 		/* deal with interrupts that should affect tracing */
    358 		set_tracelevel();
    359 
    360 		if (stopint != 0) {
    361 			if (supplier) {
    362 				rip_bcast(0);
    363 				rdisc_adv();
    364 			}
    365 			trace_off("exiting with signal %d\n", stopint);
    366 			exit(stopint | 128);
    367 		}
    368 
    369 		/* look for new or dead interfaces */
    370 		timevalsub(&wtime, &ifinit_timer, &now);
    371 		if (wtime.tv_sec <= 0) {
    372 			wtime.tv_sec = 0;
    373 			ifinit();
    374 			rip_query();
    375 			continue;
    376 		}
    377 
    378 		/* If it is time, then broadcast our routes.
    379 		 */
    380 		if (supplier || advertise_mhome) {
    381 			timevalsub(&t2, &next_bcast, &now);
    382 			if (t2.tv_sec <= 0) {
    383 				/* Synchronize the aging and broadcast
    384 				 * timers to minimize awakenings
    385 				 */
    386 				age(0);
    387 
    388 				rip_bcast(0);
    389 
    390 				/* It is desirable to send routing updates
    391 				 * regularly.  So schedule the next update
    392 				 * 30 seconds after the previous one was
    393 				 * secheduled, instead of 30 seconds after
    394 				 * the previous update was finished.
    395 				 * Even if we just started after discovering
    396 				 * a 2nd interface or were otherwise delayed,
    397 				 * pick a 30-second aniversary of the
    398 				 * original broadcast time.
    399 				 */
    400 				n = 1 + (0-t2.tv_sec)/SUPPLY_INTERVAL;
    401 				next_bcast.tv_sec += n*SUPPLY_INTERVAL;
    402 
    403 				continue;
    404 			}
    405 
    406 			if (timercmp(&t2, &wtime, <))
    407 				wtime = t2;
    408 		}
    409 
    410 		/* If we need a flash update, either do it now or
    411 		 * set the delay to end when it is time.
    412 		 *
    413 		 * If we are within MIN_WAITTIME seconds of a full update,
    414 		 * do not bother.
    415 		 */
    416 		if (need_flash
    417 		    && supplier
    418 		    && no_flash.tv_sec+MIN_WAITTIME < next_bcast.tv_sec) {
    419 			/* accurate to the millisecond */
    420 			if (!timercmp(&no_flash, &now, >))
    421 				rip_bcast(1);
    422 			timevalsub(&t2, &no_flash, &now);
    423 			if (timercmp(&t2, &wtime, <))
    424 				wtime = t2;
    425 		}
    426 
    427 		/* trigger the main aging timer.
    428 		 */
    429 		timevalsub(&t2, &age_timer, &now);
    430 		if (t2.tv_sec <= 0) {
    431 			age(0);
    432 			continue;
    433 		}
    434 		if (timercmp(&t2, &wtime, <))
    435 			wtime = t2;
    436 
    437 		/* update the kernel routing table
    438 		 */
    439 		timevalsub(&t2, &need_kern, &now);
    440 		if (t2.tv_sec <= 0) {
    441 			age(0);
    442 			continue;
    443 		}
    444 		if (timercmp(&t2, &wtime, <))
    445 			wtime = t2;
    446 
    447 		/* take care of router discovery,
    448 		 * but do it to the millisecond
    449 		 */
    450 		if (!timercmp(&rdisc_timer, &now, >)) {
    451 			rdisc_age(0);
    452 			continue;
    453 		}
    454 		timevalsub(&t2, &rdisc_timer, &now);
    455 		if (timercmp(&t2, &wtime, <))
    456 			wtime = t2;
    457 
    458 
    459 		/* wait for input or a timer to expire.
    460 		 */
    461 		trace_flush();
    462 		ibits = fdbits;
    463 		n = select(sock_max, &ibits, 0, 0, &wtime);
    464 		if (n <= 0) {
    465 			if (n < 0 && errno != EINTR && errno != EAGAIN)
    466 				BADERR(1,"select");
    467 			continue;
    468 		}
    469 
    470 		if (FD_ISSET(rt_sock, &ibits)) {
    471 			read_rt();
    472 			n--;
    473 		}
    474 		if (rdisc_sock >= 0 && FD_ISSET(rdisc_sock, &ibits)) {
    475 			read_d();
    476 			n--;
    477 		}
    478 		if (rip_sock >= 0 && FD_ISSET(rip_sock, &ibits)) {
    479 			read_rip(rip_sock, 0);
    480 			n--;
    481 		}
    482 
    483 		for (ifp = ifnet; n > 0 && 0 != ifp; ifp = ifp->int_next) {
    484 			if (ifp->int_rip_sock >= 0
    485 			    && FD_ISSET(ifp->int_rip_sock, &ibits)) {
    486 				read_rip(ifp->int_rip_sock, ifp);
    487 				n--;
    488 			}
    489 		}
    490 	}
    491 }
    492 
    493 
    494 /* ARGSUSED */
    495 void
    496 sigalrm(int sig)
    497 {
    498 	/* Historically, SIGALRM would cause the daemon to check for
    499 	 * new and broken interfaces.
    500 	 */
    501 	ifinit_timer.tv_sec = now.tv_sec;
    502 	trace_act("SIGALRM\n");
    503 }
    504 
    505 
    506 /* watch for fatal signals */
    507 void
    508 sigterm(int sig)
    509 {
    510 	stopint = sig;
    511 	(void)signal(sig, SIG_DFL);	/* catch it only once */
    512 }
    513 
    514 
    515 void
    516 fix_select(void)
    517 {
    518 	struct interface *ifp;
    519 
    520 
    521 	FD_ZERO(&fdbits);
    522 	sock_max = 0;
    523 
    524 	FD_SET(rt_sock, &fdbits);
    525 	if (sock_max <= rt_sock)
    526 		sock_max = rt_sock+1;
    527 	if (rip_sock >= 0) {
    528 		FD_SET(rip_sock, &fdbits);
    529 		if (sock_max <= rip_sock)
    530 			sock_max = rip_sock+1;
    531 	}
    532 	for (ifp = ifnet; 0 != ifp; ifp = ifp->int_next) {
    533 		if (ifp->int_rip_sock >= 0) {
    534 			FD_SET(ifp->int_rip_sock, &fdbits);
    535 			if (sock_max <= ifp->int_rip_sock)
    536 				sock_max = ifp->int_rip_sock+1;
    537 		}
    538 	}
    539 	if (rdisc_sock >= 0) {
    540 		FD_SET(rdisc_sock, &fdbits);
    541 		if (sock_max <= rdisc_sock)
    542 			sock_max = rdisc_sock+1;
    543 	}
    544 }
    545 
    546 
    547 void
    548 fix_sock(int sock,
    549 	 char *name)
    550 {
    551 	int on;
    552 #define MIN_SOCKBUF (4*1024)
    553 	static int rbuf;
    554 
    555 	if (fcntl(sock, F_SETFL, O_NONBLOCK) == -1)
    556 		logbad(1, "fcntl(%s) O_NONBLOCK: %s",
    557 		       name, strerror(errno));
    558 	on = 1;
    559 	if (setsockopt(sock, SOL_SOCKET,SO_BROADCAST,
    560 		       &on,sizeof(on)) < 0)
    561 		msglog("setsockopt(%s,SO_BROADCAST): %s",
    562 		       name, strerror(errno));
    563 	if (rbuf >= MIN_SOCKBUF) {
    564 		if (setsockopt(sock, SOL_SOCKET, SO_RCVBUF,
    565 			       &rbuf, sizeof(rbuf)) < 0)
    566 			msglog("setsockopt(%s,SO_RCVBUF=%d): %s",
    567 			       name, rbuf, strerror(errno));
    568 	} else {
    569 		for (rbuf = 60*1024; ; rbuf -= 4096) {
    570 			if (setsockopt(sock, SOL_SOCKET, SO_RCVBUF,
    571 				       &rbuf, sizeof(rbuf)) == 0) {
    572 				trace_act("RCVBUF=%d\n", rbuf);
    573 				break;
    574 			}
    575 			if (rbuf < MIN_SOCKBUF) {
    576 				msglog("setsockopt(%s,SO_RCVBUF = %d): %s",
    577 				       name, rbuf, strerror(errno));
    578 				break;
    579 			}
    580 		}
    581 	}
    582 }
    583 
    584 
    585 /* get a rip socket
    586  */
    587 static int				/* <0 or file descriptor */
    588 get_rip_sock(naddr addr,
    589 	     int serious)		/* 1=failure to bind is serious */
    590 {
    591 	struct sockaddr_in sin;
    592 	unsigned char ttl;
    593 	int s;
    594 
    595 
    596 	if ((s = socket(AF_INET, SOCK_DGRAM, 0)) < 0)
    597 		BADERR(1,"rip_sock = socket()");
    598 
    599 	bzero(&sin,sizeof(sin));
    600 #ifdef _HAVE_SIN_LEN
    601 	sin.sin_len = sizeof(sin);
    602 #endif
    603 	sin.sin_family = AF_INET;
    604 	sin.sin_port = htons(RIP_PORT);
    605 	sin.sin_addr.s_addr = addr;
    606 	if (bind(s, (struct sockaddr *)&sin,sizeof(sin)) < 0) {
    607 		if (serious)
    608 			BADERR(errno != EADDRINUSE, "bind(rip_sock)");
    609 		return -1;
    610 	}
    611 	fix_sock(s,"rip_sock");
    612 
    613 	ttl = 1;
    614 	if (setsockopt(s, IPPROTO_IP, IP_MULTICAST_TTL,
    615 		       &ttl, sizeof(ttl)) < 0)
    616 		DBGERR(1,"rip_sock setsockopt(IP_MULTICAST_TTL)");
    617 
    618 	return s;
    619 }
    620 
    621 
    622 /* turn off main RIP socket */
    623 void
    624 rip_off(void)
    625 {
    626 	struct interface *ifp;
    627 	register naddr addr;
    628 
    629 
    630 	if (rip_sock >= 0 && !mhome) {
    631 		trace_act("turn off RIP\n");
    632 
    633 		(void)close(rip_sock);
    634 		rip_sock = -1;
    635 
    636 		/* get non-broadcast sockets to listen to queries.
    637 		 */
    638 		for (ifp = ifnet; ifp != 0; ifp = ifp->int_next) {
    639 			if (ifp->int_rip_sock < 0
    640 			    && !(ifp->int_state & IS_ALIAS)) {
    641 				addr = ((ifp->int_if_flags & IFF_POINTOPOINT)
    642 					? ifp->int_dstaddr
    643 					: ifp->int_addr);
    644 				ifp->int_rip_sock = get_rip_sock(addr, 0);
    645 			}
    646 		}
    647 
    648 		fix_select();
    649 
    650 		age(0);
    651 	}
    652 }
    653 
    654 
    655 /* turn on RIP multicast input via an interface
    656  */
    657 static void
    658 rip_mcast_on(struct interface *ifp)
    659 {
    660 	struct ip_mreq m;
    661 
    662 	if (!IS_RIP_IN_OFF(ifp->int_state)
    663 	    && (ifp->int_if_flags & IFF_MULTICAST)
    664 #ifdef MCAST_PPP_BUG
    665 	    && !(ifp->int_if_flags & IFF_POINTOPOINT)
    666 #endif
    667 	    && !(ifp->int_state & IS_ALIAS)) {
    668 		m.imr_multiaddr.s_addr = htonl(INADDR_RIP_GROUP);
    669 		m.imr_interface.s_addr = ((ifp->int_if_flags & IFF_POINTOPOINT)
    670 					  ? ifp->int_dstaddr
    671 					  : ifp->int_addr);
    672 		if (setsockopt(rip_sock,IPPROTO_IP, IP_ADD_MEMBERSHIP,
    673 			       &m, sizeof(m)) < 0)
    674 			LOGERR("setsockopt(IP_ADD_MEMBERSHIP RIP)");
    675 	}
    676 }
    677 
    678 
    679 /* Prepare socket used for RIP.
    680  */
    681 void
    682 rip_on(struct interface *ifp)
    683 {
    684 	/* If the main RIP socket is already alive, only start receiving
    685 	 * multicasts for this interface.
    686 	 */
    687 	if (rip_sock >= 0) {
    688 		if (ifp != 0)
    689 			rip_mcast_on(ifp);
    690 		return;
    691 	}
    692 
    693 	/* If the main RIP socket is off, and it makes sense to turn it on,
    694 	 * turn it on for all of the interfaces.
    695 	 */
    696 	if (rip_interfaces > 0 && !rdisc_ok) {
    697 		trace_act("turn on RIP\n");
    698 
    699 		/* Close all of the query sockets so that we can open
    700 		 * the main socket.  SO_REUSEPORT is not a solution,
    701 		 * since that would let two daemons bind to the broadcast
    702 		 * socket.
    703 		 */
    704 		for (ifp = ifnet; ifp != 0; ifp = ifp->int_next) {
    705 			if (ifp->int_rip_sock >= 0) {
    706 				(void)close(ifp->int_rip_sock);
    707 				ifp->int_rip_sock = -1;
    708 			}
    709 		}
    710 
    711 		rip_sock = get_rip_sock(INADDR_ANY, 1);
    712 		rip_sock_mcast = 0;
    713 
    714 		/* Do not advertise anything until we have heard something
    715 		 */
    716 		if (next_bcast.tv_sec < now.tv_sec+MIN_WAITTIME)
    717 			next_bcast.tv_sec = now.tv_sec+MIN_WAITTIME;
    718 
    719 		for (ifp = ifnet; ifp != 0; ifp = ifp->int_next) {
    720 			if (!IS_RIP_IN_OFF(ifp->int_state))
    721 				ifp->int_state &= ~IS_RIP_QUERIED;
    722 			rip_mcast_on(ifp);
    723 		}
    724 
    725 		ifinit_timer.tv_sec = now.tv_sec;
    726 
    727 		fix_select();
    728 
    729 	} else if (ifp != 0
    730 		   && ifp->int_rip_sock < 0
    731 		   && !(ifp->int_state & IS_ALIAS)) {
    732 		/* RIP is off, so ensure there are sockets on which
    733 		 * to listen for queries.
    734 		 */
    735 		ifp->int_rip_sock = get_rip_sock(ifp->int_addr, 0);
    736 
    737 		fix_select();
    738 	}
    739 }
    740 
    741 
    742 /* get a random instant in an interval
    743  */
    744 void
    745 intvl_random(struct timeval *tp,	/* put value here */
    746 	     u_long lo,			/* value is after this second */
    747 	     u_long hi)			/* and before this */
    748 {
    749 	tp->tv_sec = (time_t)(hi == lo
    750 			      ? lo
    751 			      : (lo + random() % ((hi - lo))));
    752 	tp->tv_usec = random() % 1000000;
    753 }
    754 
    755 
    756 void
    757 timevaladd(struct timeval *t1,
    758 	   struct timeval *t2)
    759 {
    760 
    761 	t1->tv_sec += t2->tv_sec;
    762 	if ((t1->tv_usec += t2->tv_usec) > 1000000) {
    763 		t1->tv_sec++;
    764 		t1->tv_usec -= 1000000;
    765 	}
    766 }
    767 
    768 
    769 /* t1 = t2 - t3
    770  */
    771 static void
    772 timevalsub(struct timeval *t1,
    773 	   struct timeval *t2,
    774 	   struct timeval *t3)
    775 {
    776 	t1->tv_sec = t2->tv_sec - t3->tv_sec;
    777 	if ((t1->tv_usec = t2->tv_usec - t3->tv_usec) < 0) {
    778 		t1->tv_sec--;
    779 		t1->tv_usec += 1000000;
    780 	}
    781 }
    782 
    783 
    784 void
    785 msglog(char *p, ...)
    786 {
    787 	va_list args;
    788 
    789 	trace_flush();
    790 
    791 	va_start(args, p);
    792 	vsyslog(LOG_ERR, p, args);
    793 
    794 	if (ftrace != 0) {
    795 		if (ftrace == stdout)
    796 			(void)fputs("routed: ", ftrace);
    797 		(void)vfprintf(ftrace, p, args);
    798 		(void)fputc('\n', ftrace);
    799 	}
    800 }
    801 
    802 
    803 void
    804 logbad(int dump, char *p, ...)
    805 {
    806 	va_list args;
    807 
    808 	trace_flush();
    809 
    810 	va_start(args, p);
    811 	vsyslog(LOG_ERR, p, args);
    812 
    813 	(void)fputs("routed: ", stderr);
    814 	(void)vfprintf(stderr, p, args);
    815 	(void)fputs("; giving up\n",stderr);
    816 	(void)fflush(stderr);
    817 
    818 	if (dump)
    819 		abort();
    820 	exit(1);
    821 }
    822