xref: /original-bsd/sbin/routed/main.c (revision e61fc7ea)
1 /*
2  * Copyright (c) 1983, 1988 Regents of the University of California.
3  * All rights reserved.
4  *
5  * %sccs.include.redist.c%
6  */
7 
8 #ifndef lint
9 char copyright[] =
10 "@(#) Copyright (c) 1983, 1988 Regents of the University of California.\n\
11  All rights reserved.\n";
12 #endif /* not lint */
13 
14 #ifndef lint
15 static char sccsid[] = "@(#)main.c	5.21 (Berkeley) 06/29/90";
16 #endif /* not lint */
17 
18 /*
19  * Routing Table Management Daemon
20  */
21 #include "defs.h"
22 #include <sys/ioctl.h>
23 #include <sys/file.h>
24 
25 #include <net/if.h>
26 
27 #include <sys/errno.h>
28 #include <sys/signal.h>
29 #include <sys/syslog.h>
30 #include "pathnames.h"
31 
32 int	supplier = -1;		/* process should supply updates */
33 int	gateway = 0;		/* 1 if we are a gateway to parts beyond */
34 int	debug = 0;
35 int	bufspace = 127*1024;	/* max. input buffer size to request */
36 
37 struct	rip *msg = (struct rip *)packet;
38 int	hup(), rtdeleteall(), sigtrace();
39 
40 main(argc, argv)
41 	int argc;
42 	char *argv[];
43 {
44 	int n, cc, nfd, omask, tflags = 0;
45 	struct sockaddr from;
46 	struct timeval *tvp, waittime;
47 	struct itimerval itval;
48 	register struct rip *query = msg;
49 	fd_set ibits;
50 	u_char retry;
51 
52 	argv0 = argv;
53 #if BSD >= 43
54 	openlog("routed", LOG_PID | LOG_ODELAY, LOG_DAEMON);
55 	setlogmask(LOG_UPTO(LOG_WARNING));
56 #else
57 	openlog("routed", LOG_PID);
58 #define LOG_UPTO(x) (x)
59 #define setlogmask(x) (x)
60 #endif
61 	sp = getservbyname("router", "udp");
62 	if (sp == NULL) {
63 		fprintf(stderr, "routed: router/udp: unknown service\n");
64 		exit(1);
65 	}
66 	addr.sin_family = AF_INET;
67 	addr.sin_port = sp->s_port;
68 	s = getsocket(AF_INET, SOCK_DGRAM, &addr);
69 	if (s < 0)
70 		exit(1);
71 	argv++, argc--;
72 	while (argc > 0 && **argv == '-') {
73 		if (strcmp(*argv, "-s") == 0) {
74 			supplier = 1;
75 			argv++, argc--;
76 			continue;
77 		}
78 		if (strcmp(*argv, "-q") == 0) {
79 			supplier = 0;
80 			argv++, argc--;
81 			continue;
82 		}
83 		if (strcmp(*argv, "-t") == 0) {
84 			tflags++;
85 			setlogmask(LOG_UPTO(LOG_DEBUG));
86 			argv++, argc--;
87 			continue;
88 		}
89 		if (strcmp(*argv, "-d") == 0) {
90 			debug++;
91 			setlogmask(LOG_UPTO(LOG_DEBUG));
92 			argv++, argc--;
93 			continue;
94 		}
95 		if (strcmp(*argv, "-g") == 0) {
96 			gateway = 1;
97 			argv++, argc--;
98 			continue;
99 		}
100 		fprintf(stderr,
101 			"usage: routed [ -s ] [ -q ] [ -t ] [ -g ]\n");
102 		exit(1);
103 	}
104 
105 	if (debug == 0)
106 		daemon(0, 0);
107 	/*
108 	 * Any extra argument is considered
109 	 * a tracing log file.
110 	 */
111 	if (argc > 0)
112 		traceon(*argv);
113 	while (tflags-- > 0)
114 		bumploglevel();
115 
116 	(void) gettimeofday(&now, (struct timezone *)NULL);
117 	/*
118 	 * Collect an initial view of the world by
119 	 * checking the interface configuration and the gateway kludge
120 	 * file.  Then, send a request packet on all
121 	 * directly connected networks to find out what
122 	 * everyone else thinks.
123 	 */
124 	rtinit();
125 	ifinit();
126 	gwkludge();
127 	if (gateway > 0)
128 		rtdefault();
129 	if (supplier < 0)
130 		supplier = 0;
131 	query->rip_cmd = RIPCMD_REQUEST;
132 	query->rip_vers = RIPVERSION;
133 	if (sizeof(query->rip_nets[0].rip_dst.sa_family) > 1)	/* XXX */
134 		query->rip_nets[0].rip_dst.sa_family = htons((u_short)AF_UNSPEC);
135 	else
136 		query->rip_nets[0].rip_dst.sa_family = AF_UNSPEC;
137 	query->rip_nets[0].rip_metric = htonl((u_long)HOPCNT_INFINITY);
138 	toall(sendmsg);
139 	signal(SIGALRM, timer);
140 	signal(SIGHUP, hup);
141 	signal(SIGTERM, hup);
142 	signal(SIGINT, rtdeleteall);
143 	signal(SIGUSR1, sigtrace);
144 	signal(SIGUSR2, sigtrace);
145 	itval.it_interval.tv_sec = TIMER_RATE;
146 	itval.it_value.tv_sec = TIMER_RATE;
147 	itval.it_interval.tv_usec = 0;
148 	itval.it_value.tv_usec = 0;
149 	srandom(getpid());
150 	if (setitimer(ITIMER_REAL, &itval, (struct itimerval *)NULL) < 0)
151 		syslog(LOG_ERR, "setitimer: %m\n");
152 
153 	FD_ZERO(&ibits);
154 	nfd = s + 1;			/* 1 + max(fd's) */
155 	for (;;) {
156 		FD_SET(s, &ibits);
157 		/*
158 		 * If we need a dynamic update that was held off,
159 		 * needupdate will be set, and nextbcast is the time
160 		 * by which we want select to return.  Compute time
161 		 * until dynamic update should be sent, and select only
162 		 * until then.  If we have already passed nextbcast,
163 		 * just poll.
164 		 */
165 		if (needupdate) {
166 			waittime = nextbcast;
167 			timevalsub(&waittime, &now);
168 			if (waittime.tv_sec < 0) {
169 				waittime.tv_sec = 0;
170 				waittime.tv_usec = 0;
171 			}
172 			if (traceactions)
173 				fprintf(ftrace,
174 				 "select until dynamic update %d/%d sec/usec\n",
175 				    waittime.tv_sec, waittime.tv_usec);
176 			tvp = &waittime;
177 		} else
178 			tvp = (struct timeval *)NULL;
179 		n = select(nfd, &ibits, 0, 0, tvp);
180 		if (n <= 0) {
181 			/*
182 			 * Need delayed dynamic update if select returned
183 			 * nothing and we timed out.  Otherwise, ignore
184 			 * errors (e.g. EINTR).
185 			 */
186 			if (n < 0) {
187 				if (errno == EINTR)
188 					continue;
189 				syslog(LOG_ERR, "select: %m");
190 			}
191 			omask = sigblock(sigmask(SIGALRM));
192 			if (n == 0 && needupdate) {
193 				if (traceactions)
194 					fprintf(ftrace,
195 					    "send delayed dynamic update\n");
196 				(void) gettimeofday(&now,
197 					    (struct timezone *)NULL);
198 				toall(supply, RTS_CHANGED,
199 				    (struct interface *)NULL);
200 				lastbcast = now;
201 				needupdate = 0;
202 				nextbcast.tv_sec = 0;
203 			}
204 			sigsetmask(omask);
205 			continue;
206 		}
207 		(void) gettimeofday(&now, (struct timezone *)NULL);
208 		omask = sigblock(sigmask(SIGALRM));
209 #ifdef doesntwork
210 /*
211 printf("s %d, ibits %x index %d, mod %d, sh %x, or %x &ibits %x\n",
212 	s,
213 	ibits.fds_bits[0],
214 	(s)/(sizeof(fd_mask) * 8),
215 	((s) % (sizeof(fd_mask) * 8)),
216 	(1 << ((s) % (sizeof(fd_mask) * 8))),
217 	ibits.fds_bits[(s)/(sizeof(fd_mask) * 8)] & (1 << ((s) % (sizeof(fd_mask) * 8))),
218 	&ibits
219 	);
220 */
221 		if (FD_ISSET(s, &ibits))
222 #else
223 		if (ibits.fds_bits[s/32] & (1 << s))
224 #endif
225 			process(s);
226 		/* handle ICMP redirects */
227 		sigsetmask(omask);
228 	}
229 }
230 
231 timevaladd(t1, t2)
232 	struct timeval *t1, *t2;
233 {
234 
235 	t1->tv_sec += t2->tv_sec;
236 	if ((t1->tv_usec += t2->tv_usec) > 1000000) {
237 		t1->tv_sec++;
238 		t1->tv_usec -= 1000000;
239 	}
240 }
241 
242 timevalsub(t1, t2)
243 	struct timeval *t1, *t2;
244 {
245 
246 	t1->tv_sec -= t2->tv_sec;
247 	if ((t1->tv_usec -= t2->tv_usec) < 0) {
248 		t1->tv_sec--;
249 		t1->tv_usec += 1000000;
250 	}
251 }
252 
253 process(fd)
254 	int fd;
255 {
256 	struct sockaddr from;
257 	int fromlen, cc;
258 	union {
259 		char	buf[MAXPACKETSIZE+1];
260 		struct	rip rip;
261 	} inbuf;
262 
263 	for (;;) {
264 		fromlen = sizeof (from);
265 		cc = recvfrom(fd, &inbuf, sizeof (inbuf), 0, &from, &fromlen);
266 		if (cc <= 0) {
267 			if (cc < 0 && errno != EWOULDBLOCK)
268 				perror("recvfrom");
269 			break;
270 		}
271 		if (fromlen != sizeof (struct sockaddr_in))
272 			break;
273 		rip_input(&from, &inbuf.rip, cc);
274 	}
275 }
276 
277 getsocket(domain, type, sin)
278 	int domain, type;
279 	struct sockaddr_in *sin;
280 {
281 	int sock, on = 1;
282 
283 	if ((sock = socket(domain, type, 0)) < 0) {
284 		perror("socket");
285 		syslog(LOG_ERR, "socket: %m");
286 		return (-1);
287 	}
288 #ifdef SO_BROADCAST
289 	if (setsockopt(sock, SOL_SOCKET, SO_BROADCAST, &on, sizeof (on)) < 0) {
290 		syslog(LOG_ERR, "setsockopt SO_BROADCAST: %m");
291 		close(sock);
292 		return (-1);
293 	}
294 #endif
295 #ifdef SO_RCVBUF
296 	for (on = bufspace; ; on -= 1024) {
297 		if (setsockopt(sock, SOL_SOCKET, SO_RCVBUF,
298 		    &on, sizeof (on)) == 0)
299 			break;
300 		if (on <= 8*1024) {
301 			syslog(LOG_ERR, "setsockopt SO_RCVBUF: %m");
302 			break;
303 		}
304 	}
305 	if (traceactions)
306 		fprintf(ftrace, "recv buf %d\n", on);
307 #endif
308 	if (bind(sock, sin, sizeof (*sin), 0) < 0) {
309 		perror("bind");
310 		syslog(LOG_ERR, "bind: %m");
311 		close(sock);
312 		return (-1);
313 	}
314 	if (fcntl(sock, F_SETFL, FNDELAY) == -1)
315 		syslog(LOG_ERR, "fcntl FNDELAY: %m\n");
316 	return (sock);
317 }
318