xref: /netbsd-src/sbin/routed/main.c (revision ae1bfcddc410612bc8c58b807e1830becb69a24c)
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  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #ifndef lint
35 static char copyright[] =
36 "@(#) Copyright (c) 1983, 1988, 1993\n\
37 	The Regents of the University of California.  All rights reserved.\n";
38 #endif /* not lint */
39 
40 #ifndef lint
41 /*static char sccsid[] = "from: @(#)main.c	8.1 (Berkeley) 6/5/93";*/
42 static char *rcsid = "$Id: main.c,v 1.5 1994/05/13 08:04:43 mycroft Exp $";
43 #endif /* not lint */
44 
45 /*
46  * Routing Table Management Daemon
47  */
48 #include "defs.h"
49 #include <sys/ioctl.h>
50 #include <sys/file.h>
51 
52 #include <net/if.h>
53 
54 #include <sys/errno.h>
55 #include <sys/signal.h>
56 #include <sys/syslog.h>
57 #include "pathnames.h"
58 
59 int	supplier = -1;		/* process should supply updates */
60 int	gateway = 0;		/* 1 if we are a gateway to parts beyond */
61 int	debug = 0;
62 int	bufspace = 127*1024;	/* max. input buffer size to request */
63 
64 struct	rip *msg = (struct rip *)packet;
65 void	hup(), rtdeleteall(), sigtrace(), timer();
66 
67 main(argc, argv)
68 	int argc;
69 	char *argv[];
70 {
71 	int n, cc, nfd, omask, tflags = 0;
72 	struct sockaddr from;
73 	struct timeval *tvp, waittime;
74 	struct itimerval itval;
75 	register struct rip *query = msg;
76 	fd_set ibits;
77 	u_char retry;
78 
79 	argv0 = argv;
80 #if BSD >= 43
81 	openlog("routed", LOG_PID | LOG_ODELAY, LOG_DAEMON);
82 	setlogmask(LOG_UPTO(LOG_WARNING));
83 #else
84 	openlog("routed", LOG_PID);
85 #define LOG_UPTO(x) (x)
86 #define setlogmask(x) (x)
87 #endif
88 	sp = getservbyname("router", "udp");
89 	if (sp == NULL) {
90 		fprintf(stderr, "routed: router/udp: unknown service\n");
91 		exit(1);
92 	}
93 	addr.sin_family = AF_INET;
94 	addr.sin_port = sp->s_port;
95 	r = socket(AF_ROUTE, SOCK_RAW, 0);
96 	/* later, get smart about lookingforinterfaces */
97 	if (r)
98 		shutdown(r, 0); /* for now, don't want reponses */
99 	else {
100 		fprintf(stderr, "routed: no routing socket\n");
101 		exit(1);
102 	}
103 	s = getsocket(AF_INET, SOCK_DGRAM, &addr);
104 	if (s < 0)
105 		exit(1);
106 	argv++, argc--;
107 	while (argc > 0 && **argv == '-') {
108 		if (strcmp(*argv, "-s") == 0) {
109 			supplier = 1;
110 			argv++, argc--;
111 			continue;
112 		}
113 		if (strcmp(*argv, "-q") == 0) {
114 			supplier = 0;
115 			argv++, argc--;
116 			continue;
117 		}
118 		if (strcmp(*argv, "-t") == 0) {
119 			tflags++;
120 			setlogmask(LOG_UPTO(LOG_DEBUG));
121 			argv++, argc--;
122 			continue;
123 		}
124 		if (strcmp(*argv, "-d") == 0) {
125 			debug++;
126 			setlogmask(LOG_UPTO(LOG_DEBUG));
127 			argv++, argc--;
128 			continue;
129 		}
130 		if (strcmp(*argv, "-g") == 0) {
131 			gateway = 1;
132 			argv++, argc--;
133 			continue;
134 		}
135 		fprintf(stderr,
136 			"usage: routed [ -s ] [ -q ] [ -t ] [ -g ]\n");
137 		exit(1);
138 	}
139 
140 	if (debug == 0 && tflags == 0)
141 		daemon(0, 0);
142 	/*
143 	 * Any extra argument is considered
144 	 * a tracing log file.
145 	 */
146 	if (argc > 0)
147 		traceon(*argv);
148 	while (tflags-- > 0)
149 		bumploglevel();
150 
151 	(void) gettimeofday(&now, (struct timezone *)NULL);
152 	/*
153 	 * Collect an initial view of the world by
154 	 * checking the interface configuration and the gateway kludge
155 	 * file.  Then, send a request packet on all
156 	 * directly connected networks to find out what
157 	 * everyone else thinks.
158 	 */
159 	rtinit();
160 	ifinit();
161 	gwkludge();
162 	if (gateway > 0)
163 		rtdefault();
164 	if (supplier < 0)
165 		supplier = 0;
166 	query->rip_cmd = RIPCMD_REQUEST;
167 	query->rip_vers = RIPVERSION;
168 	if (sizeof(query->rip_nets[0].rip_dst.sa_family) > 1)	/* XXX */
169 		query->rip_nets[0].rip_dst.sa_family = htons((u_short)AF_UNSPEC);
170 	else
171 		query->rip_nets[0].rip_dst.sa_family = AF_UNSPEC;
172 	query->rip_nets[0].rip_metric = htonl((u_long)HOPCNT_INFINITY);
173 	toall(sndmsg);
174 	signal(SIGALRM, timer);
175 	signal(SIGHUP, hup);
176 	signal(SIGTERM, hup);
177 	signal(SIGINT, rtdeleteall);
178 	signal(SIGUSR1, sigtrace);
179 	signal(SIGUSR2, sigtrace);
180 	itval.it_interval.tv_sec = TIMER_RATE;
181 	itval.it_value.tv_sec = TIMER_RATE;
182 	itval.it_interval.tv_usec = 0;
183 	itval.it_value.tv_usec = 0;
184 	srandom(getpid());
185 	if (setitimer(ITIMER_REAL, &itval, (struct itimerval *)NULL) < 0)
186 		syslog(LOG_ERR, "setitimer: %m\n");
187 
188 	FD_ZERO(&ibits);
189 	nfd = s + 1;			/* 1 + max(fd's) */
190 	for (;;) {
191 		FD_SET(s, &ibits);
192 		/*
193 		 * If we need a dynamic update that was held off,
194 		 * needupdate will be set, and nextbcast is the time
195 		 * by which we want select to return.  Compute time
196 		 * until dynamic update should be sent, and select only
197 		 * until then.  If we have already passed nextbcast,
198 		 * just poll.
199 		 */
200 		if (needupdate) {
201 			waittime = nextbcast;
202 			timevalsub(&waittime, &now);
203 			if (waittime.tv_sec < 0) {
204 				waittime.tv_sec = 0;
205 				waittime.tv_usec = 0;
206 			}
207 			if (traceactions)
208 				fprintf(ftrace,
209 				 "select until dynamic update %d/%d sec/usec\n",
210 				    waittime.tv_sec, waittime.tv_usec);
211 			tvp = &waittime;
212 		} else
213 			tvp = (struct timeval *)NULL;
214 		n = select(nfd, &ibits, 0, 0, tvp);
215 		if (n <= 0) {
216 			/*
217 			 * Need delayed dynamic update if select returned
218 			 * nothing and we timed out.  Otherwise, ignore
219 			 * errors (e.g. EINTR).
220 			 */
221 			if (n < 0) {
222 				if (errno == EINTR)
223 					continue;
224 				syslog(LOG_ERR, "select: %m");
225 			}
226 			omask = sigblock(sigmask(SIGALRM));
227 			if (n == 0 && needupdate) {
228 				if (traceactions)
229 					fprintf(ftrace,
230 					    "send delayed dynamic update\n");
231 				(void) gettimeofday(&now,
232 					    (struct timezone *)NULL);
233 				toall(supply, RTS_CHANGED,
234 				    (struct interface *)NULL);
235 				lastbcast = now;
236 				needupdate = 0;
237 				nextbcast.tv_sec = 0;
238 			}
239 			sigsetmask(omask);
240 			continue;
241 		}
242 		(void) gettimeofday(&now, (struct timezone *)NULL);
243 		omask = sigblock(sigmask(SIGALRM));
244 #ifdef doesntwork
245 /*
246 printf("s %d, ibits %x index %d, mod %d, sh %x, or %x &ibits %x\n",
247 	s,
248 	ibits.fds_bits[0],
249 	(s)/(sizeof(fd_mask) * 8),
250 	((s) % (sizeof(fd_mask) * 8)),
251 	(1 << ((s) % (sizeof(fd_mask) * 8))),
252 	ibits.fds_bits[(s)/(sizeof(fd_mask) * 8)] & (1 << ((s) % (sizeof(fd_mask) * 8))),
253 	&ibits
254 	);
255 */
256 		if (FD_ISSET(s, &ibits))
257 #else
258 		if (ibits.fds_bits[s/32] & (1 << s))
259 #endif
260 			process(s);
261 		/* handle ICMP redirects */
262 		sigsetmask(omask);
263 	}
264 }
265 
266 timevaladd(t1, t2)
267 	struct timeval *t1, *t2;
268 {
269 
270 	t1->tv_sec += t2->tv_sec;
271 	if ((t1->tv_usec += t2->tv_usec) > 1000000) {
272 		t1->tv_sec++;
273 		t1->tv_usec -= 1000000;
274 	}
275 }
276 
277 timevalsub(t1, t2)
278 	struct timeval *t1, *t2;
279 {
280 
281 	t1->tv_sec -= t2->tv_sec;
282 	if ((t1->tv_usec -= t2->tv_usec) < 0) {
283 		t1->tv_sec--;
284 		t1->tv_usec += 1000000;
285 	}
286 }
287 
288 process(fd)
289 	int fd;
290 {
291 	struct sockaddr from;
292 	int fromlen, cc;
293 	union {
294 		char	buf[MAXPACKETSIZE+1];
295 		struct	rip rip;
296 	} inbuf;
297 
298 	for (;;) {
299 		fromlen = sizeof (from);
300 		cc = recvfrom(fd, &inbuf, sizeof (inbuf), 0, &from, &fromlen);
301 		if (cc <= 0) {
302 			if (cc < 0 && errno != EWOULDBLOCK)
303 				perror("recvfrom");
304 			break;
305 		}
306 		if (fromlen != sizeof (struct sockaddr_in))
307 			break;
308 		rip_input(&from, &inbuf.rip, cc);
309 	}
310 }
311 
312 getsocket(domain, type, sin)
313 	int domain, type;
314 	struct sockaddr_in *sin;
315 {
316 	int sock, on = 1;
317 
318 	if ((sock = socket(domain, type, 0)) < 0) {
319 		perror("socket");
320 		syslog(LOG_ERR, "socket: %m");
321 		return (-1);
322 	}
323 #ifdef SO_BROADCAST
324 	if (setsockopt(sock, SOL_SOCKET, SO_BROADCAST, &on, sizeof (on)) < 0) {
325 		syslog(LOG_ERR, "setsockopt SO_BROADCAST: %m");
326 		close(sock);
327 		return (-1);
328 	}
329 #endif
330 #ifdef SO_RCVBUF
331 	for (on = bufspace; ; on -= 1024) {
332 		if (setsockopt(sock, SOL_SOCKET, SO_RCVBUF,
333 		    &on, sizeof (on)) == 0)
334 			break;
335 		if (on <= 8*1024) {
336 			syslog(LOG_ERR, "setsockopt SO_RCVBUF: %m");
337 			break;
338 		}
339 	}
340 	if (traceactions)
341 		fprintf(ftrace, "recv buf %d\n", on);
342 #endif
343 	if (bind(sock, (struct sockaddr *)sin, sizeof (*sin)) < 0) {
344 		perror("bind");
345 		syslog(LOG_ERR, "bind: %m");
346 		close(sock);
347 		return (-1);
348 	}
349 	if (fcntl(sock, F_SETFL, O_NONBLOCK) == -1)
350 		syslog(LOG_ERR, "fcntl O_NONBLOCK: %m\n");
351 	return (sock);
352 }
353