xref: /netbsd-src/sbin/routed/main.c (revision 5f7096188587a2c7c95fa3c69b78e1ec9c7923d0)
1 /*
2  * Copyright (c) 1983, 1988 Regents of the University of California.
3  * 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 char copyright[] =
36 "@(#) Copyright (c) 1983, 1988 Regents of the University of California.\n\
37  All rights reserved.\n";
38 #endif /* not lint */
39 
40 #ifndef lint
41 /*static char sccsid[] = "from: @(#)main.c	5.23 (Berkeley) 7/1/91";*/
42 static char rcsid[] = "$Id: main.c,v 1.4 1993/08/01 18:24:26 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 	s = getsocket(AF_INET, SOCK_DGRAM, &addr);
96 	if (s < 0)
97 		exit(1);
98 	argv++, argc--;
99 	while (argc > 0 && **argv == '-') {
100 		if (strcmp(*argv, "-s") == 0) {
101 			supplier = 1;
102 			argv++, argc--;
103 			continue;
104 		}
105 		if (strcmp(*argv, "-q") == 0) {
106 			supplier = 0;
107 			argv++, argc--;
108 			continue;
109 		}
110 		if (strcmp(*argv, "-t") == 0) {
111 			tflags++;
112 			setlogmask(LOG_UPTO(LOG_DEBUG));
113 			argv++, argc--;
114 			continue;
115 		}
116 		if (strcmp(*argv, "-d") == 0) {
117 			debug++;
118 			setlogmask(LOG_UPTO(LOG_DEBUG));
119 			argv++, argc--;
120 			continue;
121 		}
122 		if (strcmp(*argv, "-g") == 0) {
123 			gateway = 1;
124 			argv++, argc--;
125 			continue;
126 		}
127 		fprintf(stderr,
128 			"usage: routed [ -s ] [ -q ] [ -t ] [ -g ]\n");
129 		exit(1);
130 	}
131 
132 	if (debug == 0)
133 		daemon(0, 0);
134 	/*
135 	 * Any extra argument is considered
136 	 * a tracing log file.
137 	 */
138 	if (argc > 0)
139 		traceon(*argv);
140 	while (tflags-- > 0)
141 		bumploglevel();
142 
143 	(void) gettimeofday(&now, (struct timezone *)NULL);
144 	/*
145 	 * Collect an initial view of the world by
146 	 * checking the interface configuration and the gateway kludge
147 	 * file.  Then, send a request packet on all
148 	 * directly connected networks to find out what
149 	 * everyone else thinks.
150 	 */
151 	rtinit();
152 	ifinit();
153 	gwkludge();
154 	if (gateway > 0)
155 		rtdefault();
156 	if (supplier < 0)
157 		supplier = 0;
158 	query->rip_cmd = RIPCMD_REQUEST;
159 	query->rip_vers = RIPVERSION;
160 	if (sizeof(query->rip_nets[0].rip_dst.sa_family) > 1)	/* XXX */
161 		query->rip_nets[0].rip_dst.sa_family = htons((u_short)AF_UNSPEC);
162 	else
163 		query->rip_nets[0].rip_dst.sa_family = AF_UNSPEC;
164 	query->rip_nets[0].rip_metric = htonl((u_long)HOPCNT_INFINITY);
165 	toall(sndmsg);
166 	signal(SIGALRM, timer);
167 	signal(SIGHUP, hup);
168 	signal(SIGTERM, hup);
169 	signal(SIGINT, rtdeleteall);
170 	signal(SIGUSR1, sigtrace);
171 	signal(SIGUSR2, sigtrace);
172 	itval.it_interval.tv_sec = TIMER_RATE;
173 	itval.it_value.tv_sec = TIMER_RATE;
174 	itval.it_interval.tv_usec = 0;
175 	itval.it_value.tv_usec = 0;
176 	srandom(getpid());
177 	if (setitimer(ITIMER_REAL, &itval, (struct itimerval *)NULL) < 0)
178 		syslog(LOG_ERR, "setitimer: %m\n");
179 
180 	FD_ZERO(&ibits);
181 	nfd = s + 1;			/* 1 + max(fd's) */
182 	for (;;) {
183 		FD_SET(s, &ibits);
184 		/*
185 		 * If we need a dynamic update that was held off,
186 		 * needupdate will be set, and nextbcast is the time
187 		 * by which we want select to return.  Compute time
188 		 * until dynamic update should be sent, and select only
189 		 * until then.  If we have already passed nextbcast,
190 		 * just poll.
191 		 */
192 		if (needupdate) {
193 			waittime = nextbcast;
194 			timevalsub(&waittime, &now);
195 			if (waittime.tv_sec < 0) {
196 				waittime.tv_sec = 0;
197 				waittime.tv_usec = 0;
198 			}
199 			if (traceactions)
200 				fprintf(ftrace,
201 				 "select until dynamic update %d/%d sec/usec\n",
202 				    waittime.tv_sec, waittime.tv_usec);
203 			tvp = &waittime;
204 		} else
205 			tvp = (struct timeval *)NULL;
206 		n = select(nfd, &ibits, 0, 0, tvp);
207 		if (n <= 0) {
208 			/*
209 			 * Need delayed dynamic update if select returned
210 			 * nothing and we timed out.  Otherwise, ignore
211 			 * errors (e.g. EINTR).
212 			 */
213 			if (n < 0) {
214 				if (errno == EINTR)
215 					continue;
216 				syslog(LOG_ERR, "select: %m");
217 			}
218 			omask = sigblock(sigmask(SIGALRM));
219 			if (n == 0 && needupdate) {
220 				if (traceactions)
221 					fprintf(ftrace,
222 					    "send delayed dynamic update\n");
223 				(void) gettimeofday(&now,
224 					    (struct timezone *)NULL);
225 				toall(supply, RTS_CHANGED,
226 				    (struct interface *)NULL);
227 				lastbcast = now;
228 				needupdate = 0;
229 				nextbcast.tv_sec = 0;
230 			}
231 			sigsetmask(omask);
232 			continue;
233 		}
234 		(void) gettimeofday(&now, (struct timezone *)NULL);
235 		omask = sigblock(sigmask(SIGALRM));
236 #ifdef doesntwork
237 /*
238 printf("s %d, ibits %x index %d, mod %d, sh %x, or %x &ibits %x\n",
239 	s,
240 	ibits.fds_bits[0],
241 	(s)/(sizeof(fd_mask) * 8),
242 	((s) % (sizeof(fd_mask) * 8)),
243 	(1 << ((s) % (sizeof(fd_mask) * 8))),
244 	ibits.fds_bits[(s)/(sizeof(fd_mask) * 8)] & (1 << ((s) % (sizeof(fd_mask) * 8))),
245 	&ibits
246 	);
247 */
248 		if (FD_ISSET(s, &ibits))
249 #else
250 		if (ibits.fds_bits[s/32] & (1 << s))
251 #endif
252 			process(s);
253 		/* handle ICMP redirects */
254 		sigsetmask(omask);
255 	}
256 }
257 
258 timevaladd(t1, t2)
259 	struct timeval *t1, *t2;
260 {
261 
262 	t1->tv_sec += t2->tv_sec;
263 	if ((t1->tv_usec += t2->tv_usec) > 1000000) {
264 		t1->tv_sec++;
265 		t1->tv_usec -= 1000000;
266 	}
267 }
268 
269 timevalsub(t1, t2)
270 	struct timeval *t1, *t2;
271 {
272 
273 	t1->tv_sec -= t2->tv_sec;
274 	if ((t1->tv_usec -= t2->tv_usec) < 0) {
275 		t1->tv_sec--;
276 		t1->tv_usec += 1000000;
277 	}
278 }
279 
280 process(fd)
281 	int fd;
282 {
283 	struct sockaddr from;
284 	int fromlen, cc;
285 	union {
286 		char	buf[MAXPACKETSIZE+1];
287 		struct	rip rip;
288 	} inbuf;
289 
290 	for (;;) {
291 		fromlen = sizeof (from);
292 		cc = recvfrom(fd, &inbuf, sizeof (inbuf), 0, &from, &fromlen);
293 		if (cc <= 0) {
294 			if (cc < 0 && errno != EWOULDBLOCK)
295 				perror("recvfrom");
296 			break;
297 		}
298 		if (fromlen != sizeof (struct sockaddr_in))
299 			break;
300 		rip_input(&from, &inbuf.rip, cc);
301 	}
302 }
303 
304 getsocket(domain, type, sin)
305 	int domain, type;
306 	struct sockaddr_in *sin;
307 {
308 	int sock, on = 1;
309 
310 	if ((sock = socket(domain, type, 0)) < 0) {
311 		perror("socket");
312 		syslog(LOG_ERR, "socket: %m");
313 		return (-1);
314 	}
315 #ifdef SO_BROADCAST
316 	if (setsockopt(sock, SOL_SOCKET, SO_BROADCAST, &on, sizeof (on)) < 0) {
317 		syslog(LOG_ERR, "setsockopt SO_BROADCAST: %m");
318 		close(sock);
319 		return (-1);
320 	}
321 #endif
322 #ifdef SO_RCVBUF
323 	for (on = bufspace; ; on -= 1024) {
324 		if (setsockopt(sock, SOL_SOCKET, SO_RCVBUF,
325 		    &on, sizeof (on)) == 0)
326 			break;
327 		if (on <= 8*1024) {
328 			syslog(LOG_ERR, "setsockopt SO_RCVBUF: %m");
329 			break;
330 		}
331 	}
332 	if (traceactions)
333 		fprintf(ftrace, "recv buf %d\n", on);
334 #endif
335 	if (bind(sock, (struct sockaddr *)sin, sizeof (*sin)) < 0) {
336 		perror("bind");
337 		syslog(LOG_ERR, "bind: %m");
338 		close(sock);
339 		return (-1);
340 	}
341 	if (fcntl(sock, F_SETFL, O_NONBLOCK) == -1)
342 		syslog(LOG_ERR, "fcntl O_NONBLOCK: %m\n");
343 	return (sock);
344 }
345