xref: /original-bsd/usr.sbin/syslogd/syslogd.c (revision 4a884f8b) 
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[] = "@(#)syslogd.c	5.51 (Berkeley) 03/08/93";
16 #endif /* not lint */
17 
18 /*
19  *  syslogd -- log system messages
20  *
21  * This program implements a system log. It takes a series of lines.
22  * Each line may have a priority, signified as "<n>" as
23  * the first characters of the line.  If this is
24  * not present, a default priority is used.
25  *
26  * To kill syslogd, send a signal 15 (terminate).  A signal 1 (hup) will
27  * cause it to reread its configuration file.
28  *
29  * Defined Constants:
30  *
31  * MAXLINE -- the maximimum line length that can be handled.
32  * DEFUPRI -- the default priority for user messages
33  * DEFSPRI -- the default priority for kernel messages
34  *
35  * Author: Eric Allman
36  * extensive changes by Ralph Campbell
37  * more extensive changes by Eric Allman (again)
38  */
39 
40 #define	MAXLINE		1024		/* maximum line length */
41 #define	MAXSVLINE	120		/* maximum saved line length */
42 #define DEFUPRI		(LOG_USER|LOG_NOTICE)
43 #define DEFSPRI		(LOG_KERN|LOG_CRIT)
44 #define TIMERINTVL	30		/* interval for checking flush, mark */
45 
46 #include <sys/param.h>
47 #include <sys/ioctl.h>
48 #include <sys/stat.h>
49 #include <sys/wait.h>
50 #include <sys/socket.h>
51 #include <sys/msgbuf.h>
52 #include <sys/uio.h>
53 #include <sys/un.h>
54 #include <sys/time.h>
55 #include <sys/resource.h>
56 
57 #include <netinet/in.h>
58 #include <netdb.h>
59 #include <arpa/inet.h>
60 
61 #include <ctype.h>
62 #include <errno.h>
63 #include <fcntl.h>
64 #include <setjmp.h>
65 #include <signal.h>
66 #include <stdio.h>
67 #include <stdlib.h>
68 #include <string.h>
69 #include <unistd.h>
70 #include <utmp.h>
71 #include "pathnames.h"
72 
73 #define SYSLOG_NAMES
74 #include <sys/syslog.h>
75 
76 char	*LogName = _PATH_LOG;
77 char	*ConfFile = _PATH_LOGCONF;
78 char	*PidFile = _PATH_LOGPID;
79 char	ctty[] = _PATH_CONSOLE;
80 
81 #define FDMASK(fd)	(1 << (fd))
82 
83 #define	dprintf		if (Debug) printf
84 
85 #define MAXUNAMES	20	/* maximum number of user names */
86 
87 /*
88  * Flags to logmsg().
89  */
90 
91 #define IGN_CONS	0x001	/* don't print on console */
92 #define SYNC_FILE	0x002	/* do fsync on file after printing */
93 #define ADDDATE		0x004	/* add a date to the message */
94 #define MARK		0x008	/* this message is a mark */
95 
96 /*
97  * This structure represents the files that will have log
98  * copies printed.
99  */
100 
101 struct filed {
102 	struct	filed *f_next;		/* next in linked list */
103 	short	f_type;			/* entry type, see below */
104 	short	f_file;			/* file descriptor */
105 	time_t	f_time;			/* time this was last written */
106 	u_char	f_pmask[LOG_NFACILITIES+1];	/* priority mask */
107 	union {
108 		char	f_uname[MAXUNAMES][UT_NAMESIZE+1];
109 		struct {
110 			char	f_hname[MAXHOSTNAMELEN+1];
111 			struct sockaddr_in	f_addr;
112 		} f_forw;		/* forwarding address */
113 		char	f_fname[MAXPATHLEN];
114 	} f_un;
115 	char	f_prevline[MAXSVLINE];		/* last message logged */
116 	char	f_lasttime[16];			/* time of last occurrence */
117 	char	f_prevhost[MAXHOSTNAMELEN+1];	/* host from which recd. */
118 	int	f_prevpri;			/* pri of f_prevline */
119 	int	f_prevlen;			/* length of f_prevline */
120 	int	f_prevcount;			/* repetition cnt of prevline */
121 	int	f_repeatcount;			/* number of "repeated" msgs */
122 };
123 
124 /*
125  * Intervals at which we flush out "message repeated" messages,
126  * in seconds after previous message is logged.  After each flush,
127  * we move to the next interval until we reach the largest.
128  */
129 int	repeatinterval[] = { 30, 120, 600 };	/* # of secs before flush */
130 #define	MAXREPEAT ((sizeof(repeatinterval) / sizeof(repeatinterval[0])) - 1)
131 #define	REPEATTIME(f)	((f)->f_time + repeatinterval[(f)->f_repeatcount])
132 #define	BACKOFF(f)	{ if (++(f)->f_repeatcount > MAXREPEAT) \
133 				 (f)->f_repeatcount = MAXREPEAT; \
134 			}
135 
136 /* values for f_type */
137 #define F_UNUSED	0		/* unused entry */
138 #define F_FILE		1		/* regular file */
139 #define F_TTY		2		/* terminal */
140 #define F_CONSOLE	3		/* console terminal */
141 #define F_FORW		4		/* remote machine */
142 #define F_USERS		5		/* list of users */
143 #define F_WALL		6		/* everyone logged on */
144 
145 char	*TypeNames[7] = {
146 	"UNUSED",	"FILE",		"TTY",		"CONSOLE",
147 	"FORW",		"USERS",	"WALL"
148 };
149 
150 struct	filed *Files;
151 struct	filed consfile;
152 
153 int	Debug;			/* debug flag */
154 char	LocalHostName[MAXHOSTNAMELEN+1];	/* our hostname */
155 char	*LocalDomain;		/* our local domain name */
156 int	InetInuse = 0;		/* non-zero if INET sockets are being used */
157 int	finet;			/* Internet datagram socket */
158 int	LogPort;		/* port number for INET connections */
159 int	Initialized = 0;	/* set when we have initialized ourselves */
160 int	MarkInterval = 20 * 60;	/* interval between marks in seconds */
161 int	MarkSeq = 0;		/* mark sequence number */
162 
163 void  cfline __P((char *, struct filed *));
164 char *cvthname __P((struct sockaddr_in *));
165 void  daemon __P((int, int));
166 int   decode __P((const char *, CODE *));
167 void  die __P((int));
168 void  domark __P((int));
169 void  fprintlog __P((struct filed *, int, char *));
170 void  init __P((int));
171 void  logerror __P((char *));
172 void  logmsg __P((int, char *, char *, int));
173 void  printline __P((char *, char *));
174 void  printsys __P((char *));
175 void  reapchild __P((int));
176 char *ttymsg __P((struct iovec *, int, char *, int));
177 void  usage __P((void));
178 void  wallmsg __P((struct filed *, struct iovec *));
179 
180 int
181 main(argc, argv)
182 	int argc;
183 	char *argv[];
184 {
185 	register int i;
186 	register char *p;
187 	int funix, inetm, fklog, klogm, len;
188 	struct sockaddr_un sunx, fromunix;
189 	struct sockaddr_in sin, frominet;
190 	FILE *fp;
191 	int ch;
192 	char line[MSG_BSIZE + 1];
193 
194 	while ((ch = getopt(argc, argv, "df:m:p:")) != EOF)
195 		switch((char)ch) {
196 		case 'd':		/* debug */
197 			Debug++;
198 			break;
199 		case 'f':		/* configuration file */
200 			ConfFile = optarg;
201 			break;
202 		case 'm':		/* mark interval */
203 			MarkInterval = atoi(optarg) * 60;
204 			break;
205 		case 'p':		/* path */
206 			LogName = optarg;
207 			break;
208 		case '?':
209 		default:
210 			usage();
211 		}
212 	if (argc -= optind)
213 		usage();
214 
215 	if (!Debug)
216 		daemon(0, 0);
217 	else
218 		setlinebuf(stdout);
219 
220 	consfile.f_type = F_CONSOLE;
221 	(void)strcpy(consfile.f_un.f_fname, ctty);
222 	(void)gethostname(LocalHostName, sizeof LocalHostName);
223 	if (p = index(LocalHostName, '.')) {
224 		*p++ = '\0';
225 		LocalDomain = p;
226 	} else
227 		LocalDomain = "";
228 	(void)signal(SIGTERM, die);
229 	(void)signal(SIGINT, Debug ? die : SIG_IGN);
230 	(void)signal(SIGQUIT, Debug ? die : SIG_IGN);
231 	(void)signal(SIGCHLD, reapchild);
232 	(void)signal(SIGALRM, domark);
233 	(void)alarm(TIMERINTVL);
234 	(void)unlink(LogName);
235 
236 #ifndef SUN_LEN
237 #define SUN_LEN(unp) (strlen((unp)->sun_path) + 2)
238 #endif
239 	bzero((char *)&sunx, sizeof(sunx));
240 	sunx.sun_family = AF_UNIX;
241 	(void)strncpy(sunx.sun_path, LogName, sizeof sunx.sun_path);
242 	funix = socket(AF_UNIX, SOCK_DGRAM, 0);
243 	if (funix < 0 ||
244 	    bind(funix, (struct sockaddr *)&sunx, SUN_LEN(&sunx)) < 0 ||
245 	    chmod(LogName, 0666) < 0) {
246 		(void) sprintf(line, "cannot create %s", LogName);
247 		logerror(line);
248 		dprintf("cannot create %s (%d)\n", LogName, errno);
249 		die(0);
250 	}
251 	finet = socket(AF_INET, SOCK_DGRAM, 0);
252 	inetm = 0;
253 	if (finet >= 0) {
254 		struct servent *sp;
255 
256 		sp = getservbyname("syslog", "udp");
257 		if (sp == NULL) {
258 			errno = 0;
259 			logerror("syslog/udp: unknown service");
260 			die(0);
261 		}
262 		bzero((char *)&sin, sizeof(sin));
263 		sin.sin_family = AF_INET;
264 		sin.sin_port = LogPort = sp->s_port;
265 		if (bind(finet, (struct sockaddr *)&sin, sizeof(sin)) < 0) {
266 			logerror("bind");
267 			if (!Debug)
268 				die(0);
269 		} else {
270 			inetm = FDMASK(finet);
271 			InetInuse = 1;
272 		}
273 	}
274 	if ((fklog = open(_PATH_KLOG, O_RDONLY, 0)) >= 0)
275 		klogm = FDMASK(fklog);
276 	else {
277 		dprintf("can't open %s (%d)\n", _PATH_KLOG, errno);
278 		klogm = 0;
279 	}
280 
281 	/* tuck my process id away */
282 	fp = fopen(PidFile, "w");
283 	if (fp != NULL) {
284 		fprintf(fp, "%d\n", getpid());
285 		(void) fclose(fp);
286 	}
287 
288 	dprintf("off & running....\n");
289 
290 	init(0);
291 	(void)signal(SIGHUP, init);
292 
293 	for (;;) {
294 		int nfds, readfds = FDMASK(funix) | inetm | klogm;
295 
296 		errno = 0;
297 		dprintf("readfds = %#x\n", readfds);
298 		nfds = select(20, (fd_set *)&readfds, (fd_set *)NULL,
299 		    (fd_set *)NULL, (struct timeval *)NULL);
300 		if (nfds == 0)
301 			continue;
302 		if (nfds < 0) {
303 			if (errno != EINTR)
304 				logerror("select");
305 			continue;
306 		}
307 		dprintf("got a message (%d, %#x)\n", nfds, readfds);
308 		if (readfds & klogm) {
309 			i = read(fklog, line, sizeof(line) - 1);
310 			if (i > 0) {
311 				line[i] = '\0';
312 				printsys(line);
313 			} else if (i < 0 && errno != EINTR) {
314 				logerror("klog");
315 				fklog = -1;
316 				klogm = 0;
317 			}
318 		}
319 		if (readfds & FDMASK(funix)) {
320 			len = sizeof fromunix;
321 			i = recvfrom(funix, line, MAXLINE, 0,
322 			    (struct sockaddr *)&fromunix, &len);
323 			if (i > 0) {
324 				line[i] = '\0';
325 				printline(LocalHostName, line);
326 			} else if (i < 0 && errno != EINTR)
327 				logerror("recvfrom unix");
328 		}
329 		if (readfds & inetm) {
330 			len = sizeof frominet;
331 			i = recvfrom(finet, line, MAXLINE, 0,
332 			    (struct sockaddr *)&frominet, &len);
333 			if (i > 0) {
334 				line[i] = '\0';
335 				printline(cvthname(&frominet), line);
336 			} else if (i < 0 && errno != EINTR)
337 				logerror("recvfrom inet");
338 		}
339 	}
340 }
341 
342 void
343 usage()
344 {
345 	(void)fprintf(stderr,
346 	    "usage: syslogd [-f conffile] [-m markinterval] [-p logpath]\n");
347 	exit(1);
348 }
349 
350 /*
351  * Take a raw input line, decode the message, and print the message
352  * on the appropriate log files.
353  */
354 void
355 printline(hname, msg)
356 	char *hname;
357 	char *msg;
358 {
359 	register char *p, *q;
360 	register int c;
361 	char line[MAXLINE + 1];
362 	int pri;
363 
364 	/* test for special codes */
365 	pri = DEFUPRI;
366 	p = msg;
367 	if (*p == '<') {
368 		pri = 0;
369 		while (isdigit(*++p))
370 			pri = 10 * pri + (*p - '0');
371 		if (*p == '>')
372 			++p;
373 	}
374 	if (pri &~ (LOG_FACMASK|LOG_PRIMASK))
375 		pri = DEFUPRI;
376 
377 	/* don't allow users to log kernel messages */
378 	if (LOG_FAC(pri) == LOG_KERN)
379 		pri = LOG_MAKEPRI(LOG_USER, LOG_PRI(pri));
380 
381 	q = line;
382 
383 	while ((c = *p++ & 0177) != '\0' &&
384 	    q < &line[sizeof(line) - 1])
385 		if (iscntrl(c))
386 			if (c == '\n')
387 				*q++ = ' ';
388 			else if (c == '\t')
389 				*q++ = '\t';
390 			else {
391 				*q++ = '^';
392 				*q++ = c ^ 0100;
393 			}
394 		else
395 			*q++ = c;
396 	*q = '\0';
397 
398 	logmsg(pri, line, hname, 0);
399 }
400 
401 /*
402  * Take a raw input line from /dev/klog, split and format similar to syslog().
403  */
404 void
405 printsys(msg)
406 	char *msg;
407 {
408 	register char *p, *q;
409 	register int c;
410 	char line[MAXLINE + 1];
411 	int pri, flags;
412 	char *lp;
413 
414 	(void)strcpy(line, "vmunix: ");
415 	lp = line + strlen(line);
416 	for (p = msg; *p != '\0'; ) {
417 		flags = SYNC_FILE | ADDDATE;	/* fsync file after write */
418 		pri = DEFSPRI;
419 		if (*p == '<') {
420 			pri = 0;
421 			while (isdigit(*++p))
422 				pri = 10 * pri + (*p - '0');
423 			if (*p == '>')
424 				++p;
425 		} else {
426 			/* kernel printf's come out on console */
427 			flags |= IGN_CONS;
428 		}
429 		if (pri &~ (LOG_FACMASK|LOG_PRIMASK))
430 			pri = DEFSPRI;
431 		q = lp;
432 		while (*p != '\0' && (c = *p++) != '\n' &&
433 		    q < &line[MAXLINE])
434 			*q++ = c;
435 		*q = '\0';
436 		logmsg(pri, line, LocalHostName, flags);
437 	}
438 }
439 
440 time_t	now;
441 
442 /*
443  * Log a message to the appropriate log files, users, etc. based on
444  * the priority.
445  */
446 void
447 logmsg(pri, msg, from, flags)
448 	int pri;
449 	char *msg, *from;
450 	int flags;
451 {
452 	register struct filed *f;
453 	int fac, prilev;
454 	int omask, msglen;
455 	char *timestamp;
456 
457 	dprintf("logmsg: pri %o, flags %x, from %s, msg %s\n",
458 	    pri, flags, from, msg);
459 
460 	omask = sigblock(sigmask(SIGHUP)|sigmask(SIGALRM));
461 
462 	/*
463 	 * Check to see if msg looks non-standard.
464 	 */
465 	msglen = strlen(msg);
466 	if (msglen < 16 || msg[3] != ' ' || msg[6] != ' ' ||
467 	    msg[9] != ':' || msg[12] != ':' || msg[15] != ' ')
468 		flags |= ADDDATE;
469 
470 	(void)time(&now);
471 	if (flags & ADDDATE)
472 		timestamp = ctime(&now) + 4;
473 	else {
474 		timestamp = msg;
475 		msg += 16;
476 		msglen -= 16;
477 	}
478 
479 	/* extract facility and priority level */
480 	if (flags & MARK)
481 		fac = LOG_NFACILITIES;
482 	else
483 		fac = LOG_FAC(pri);
484 	prilev = LOG_PRI(pri);
485 
486 	/* log the message to the particular outputs */
487 	if (!Initialized) {
488 		f = &consfile;
489 		f->f_file = open(ctty, O_WRONLY, 0);
490 
491 		if (f->f_file >= 0) {
492 			fprintlog(f, flags, msg);
493 			(void)close(f->f_file);
494 		}
495 		(void)sigsetmask(omask);
496 		return;
497 	}
498 	for (f = Files; f; f = f->f_next) {
499 		/* skip messages that are incorrect priority */
500 		if (f->f_pmask[fac] < prilev ||
501 		    f->f_pmask[fac] == INTERNAL_NOPRI)
502 			continue;
503 
504 		if (f->f_type == F_CONSOLE && (flags & IGN_CONS))
505 			continue;
506 
507 		/* don't output marks to recently written files */
508 		if ((flags & MARK) && (now - f->f_time) < MarkInterval / 2)
509 			continue;
510 
511 		/*
512 		 * suppress duplicate lines to this file
513 		 */
514 		if ((flags & MARK) == 0 && msglen == f->f_prevlen &&
515 		    !strcmp(msg, f->f_prevline) &&
516 		    !strcmp(from, f->f_prevhost)) {
517 			(void)strncpy(f->f_lasttime, timestamp, 15);
518 			f->f_prevcount++;
519 			dprintf("msg repeated %d times, %ld sec of %d\n",
520 			    f->f_prevcount, now - f->f_time,
521 			    repeatinterval[f->f_repeatcount]);
522 			/*
523 			 * If domark would have logged this by now,
524 			 * flush it now (so we don't hold isolated messages),
525 			 * but back off so we'll flush less often
526 			 * in the future.
527 			 */
528 			if (now > REPEATTIME(f)) {
529 				fprintlog(f, flags, (char *)NULL);
530 				BACKOFF(f);
531 			}
532 		} else {
533 			/* new line, save it */
534 			if (f->f_prevcount)
535 				fprintlog(f, 0, (char *)NULL);
536 			f->f_repeatcount = 0;
537 			(void)strncpy(f->f_lasttime, timestamp, 15);
538 			(void)strncpy(f->f_prevhost, from,
539 					sizeof(f->f_prevhost));
540 			if (msglen < MAXSVLINE) {
541 				f->f_prevlen = msglen;
542 				f->f_prevpri = pri;
543 				(void)strcpy(f->f_prevline, msg);
544 				fprintlog(f, flags, (char *)NULL);
545 			} else {
546 				f->f_prevline[0] = 0;
547 				f->f_prevlen = 0;
548 				fprintlog(f, flags, msg);
549 			}
550 		}
551 	}
552 	(void)sigsetmask(omask);
553 }
554 
555 void
556 fprintlog(f, flags, msg)
557 	register struct filed *f;
558 	int flags;
559 	char *msg;
560 {
561 	struct iovec iov[6];
562 	register struct iovec *v;
563 	register int l;
564 	char line[MAXLINE + 1], repbuf[80], greetings[200];
565 
566 	v = iov;
567 	if (f->f_type == F_WALL) {
568 		v->iov_base = greetings;
569 		v->iov_len = sprintf(greetings,
570 		    "\r\n\7Message from syslogd@%s at %.24s ...\r\n",
571 		    f->f_prevhost, ctime(&now));
572 		v++;
573 		v->iov_base = "";
574 		v->iov_len = 0;
575 		v++;
576 	} else {
577 		v->iov_base = f->f_lasttime;
578 		v->iov_len = 15;
579 		v++;
580 		v->iov_base = " ";
581 		v->iov_len = 1;
582 		v++;
583 	}
584 	v->iov_base = f->f_prevhost;
585 	v->iov_len = strlen(v->iov_base);
586 	v++;
587 	v->iov_base = " ";
588 	v->iov_len = 1;
589 	v++;
590 
591 	if (msg) {
592 		v->iov_base = msg;
593 		v->iov_len = strlen(msg);
594 	} else if (f->f_prevcount > 1) {
595 		v->iov_base = repbuf;
596 		v->iov_len = sprintf(repbuf, "last message repeated %d times",
597 		    f->f_prevcount);
598 	} else {
599 		v->iov_base = f->f_prevline;
600 		v->iov_len = f->f_prevlen;
601 	}
602 	v++;
603 
604 	dprintf("Logging to %s", TypeNames[f->f_type]);
605 	f->f_time = now;
606 
607 	switch (f->f_type) {
608 	case F_UNUSED:
609 		dprintf("\n");
610 		break;
611 
612 	case F_FORW:
613 		dprintf(" %s\n", f->f_un.f_forw.f_hname);
614 		l = sprintf(line, "<%d>%.15s %s", f->f_prevpri,
615 		    iov[0].iov_base, iov[4].iov_base);
616 		if (l > MAXLINE)
617 			l = MAXLINE;
618 		if (sendto(finet, line, l, 0,
619 		    (struct sockaddr *)&f->f_un.f_forw.f_addr,
620 		    sizeof f->f_un.f_forw.f_addr) != l) {
621 			int e = errno;
622 			(void)close(f->f_file);
623 			f->f_type = F_UNUSED;
624 			errno = e;
625 			logerror("sendto");
626 		}
627 		break;
628 
629 	case F_CONSOLE:
630 		if (flags & IGN_CONS) {
631 			dprintf(" (ignored)\n");
632 			break;
633 		}
634 		/* FALLTHROUGH */
635 
636 	case F_TTY:
637 	case F_FILE:
638 		dprintf(" %s\n", f->f_un.f_fname);
639 		if (f->f_type != F_FILE) {
640 			v->iov_base = "\r\n";
641 			v->iov_len = 2;
642 		} else {
643 			v->iov_base = "\n";
644 			v->iov_len = 1;
645 		}
646 	again:
647 		if (writev(f->f_file, iov, 6) < 0) {
648 			int e = errno;
649 			(void)close(f->f_file);
650 			/*
651 			 * Check for errors on TTY's due to loss of tty
652 			 */
653 			if ((e == EIO || e == EBADF) && f->f_type != F_FILE) {
654 				f->f_file = open(f->f_un.f_fname,
655 				    O_WRONLY|O_APPEND, 0);
656 				if (f->f_file < 0) {
657 					f->f_type = F_UNUSED;
658 					logerror(f->f_un.f_fname);
659 				} else
660 					goto again;
661 			} else {
662 				f->f_type = F_UNUSED;
663 				errno = e;
664 				logerror(f->f_un.f_fname);
665 			}
666 		} else if (flags & SYNC_FILE)
667 			(void)fsync(f->f_file);
668 		break;
669 
670 	case F_USERS:
671 	case F_WALL:
672 		dprintf("\n");
673 		v->iov_base = "\r\n";
674 		v->iov_len = 2;
675 		wallmsg(f, iov);
676 		break;
677 	}
678 	f->f_prevcount = 0;
679 }
680 
681 /*
682  *  WALLMSG -- Write a message to the world at large
683  *
684  *	Write the specified message to either the entire
685  *	world, or a list of approved users.
686  */
687 void
688 wallmsg(f, iov)
689 	register struct filed *f;
690 	struct iovec *iov;
691 {
692 	static int reenter;			/* avoid calling ourselves */
693 	register FILE *uf;
694 	register int i;
695 	struct utmp ut;
696 	char *p;
697 
698 	if (reenter++)
699 		return;
700 	if ((uf = fopen(_PATH_UTMP, "r")) == NULL) {
701 		logerror(_PATH_UTMP);
702 		reenter = 0;
703 		return;
704 	}
705 	/* NOSTRICT */
706 	while (fread((char *)&ut, sizeof ut, 1, uf) == 1) {
707 		if (ut.ut_name[0] == '\0')
708 			continue;
709 		if (f->f_type == F_WALL) {
710 			if (p = ttymsg(iov, 6, ut.ut_line, 60*5)) {
711 				errno = 0;	/* already in msg */
712 				logerror(p);
713 			}
714 			continue;
715 		}
716 		/* should we send the message to this user? */
717 		for (i = 0; i < MAXUNAMES; i++) {
718 			if (!f->f_un.f_uname[i][0])
719 				break;
720 			if (!strncmp(f->f_un.f_uname[i], ut.ut_name,
721 			    UT_NAMESIZE)) {
722 				if (p = ttymsg(iov, 6, ut.ut_line, 60*5)) {
723 					errno = 0;	/* already in msg */
724 					logerror(p);
725 				}
726 				break;
727 			}
728 		}
729 	}
730 	(void)fclose(uf);
731 	reenter = 0;
732 }
733 
734 void
735 reapchild(signo)
736 	int signo;
737 {
738 	union wait status;
739 
740 	while (wait3((int *)&status, WNOHANG, (struct rusage *)NULL) > 0)
741 		;
742 }
743 
744 /*
745  * Return a printable representation of a host address.
746  */
747 char *
748 cvthname(f)
749 	struct sockaddr_in *f;
750 {
751 	struct hostent *hp;
752 	register char *p;
753 
754 	dprintf("cvthname(%s)\n", inet_ntoa(f->sin_addr));
755 
756 	if (f->sin_family != AF_INET) {
757 		dprintf("Malformed from address\n");
758 		return ("???");
759 	}
760 	hp = gethostbyaddr((char *)&f->sin_addr,
761 	    sizeof(struct in_addr), f->sin_family);
762 	if (hp == 0) {
763 		dprintf("Host name for your address (%s) unknown\n",
764 			inet_ntoa(f->sin_addr));
765 		return (inet_ntoa(f->sin_addr));
766 	}
767 	if ((p = index(hp->h_name, '.')) && strcmp(p + 1, LocalDomain) == 0)
768 		*p = '\0';
769 	return (hp->h_name);
770 }
771 
772 void
773 domark(signo)
774 	int signo;
775 {
776 	register struct filed *f;
777 
778 	now = time((time_t *)NULL);
779 	MarkSeq += TIMERINTVL;
780 	if (MarkSeq >= MarkInterval) {
781 		logmsg(LOG_INFO, "-- MARK --", LocalHostName, ADDDATE|MARK);
782 		MarkSeq = 0;
783 	}
784 
785 	for (f = Files; f; f = f->f_next) {
786 		if (f->f_prevcount && now >= REPEATTIME(f)) {
787 			dprintf("flush %s: repeated %d times, %d sec.\n",
788 			    TypeNames[f->f_type], f->f_prevcount,
789 			    repeatinterval[f->f_repeatcount]);
790 			fprintlog(f, 0, (char *)NULL);
791 			BACKOFF(f);
792 		}
793 	}
794 	(void)alarm(TIMERINTVL);
795 }
796 
797 /*
798  * Print syslogd errors some place.
799  */
800 void
801 logerror(type)
802 	char *type;
803 {
804 	char buf[100];
805 
806 	if (errno)
807 		(void)snprintf(buf,
808 		    sizeof(buf), "syslogd: %s: %s", type, strerror(errno));
809 	else
810 		(void)snprintf(buf, sizeof(buf), "syslogd: %s", type);
811 	errno = 0;
812 	dprintf("%s\n", buf);
813 	logmsg(LOG_SYSLOG|LOG_ERR, buf, LocalHostName, ADDDATE);
814 }
815 
816 void
817 die(signo)
818 	int signo;
819 {
820 	register struct filed *f;
821 	char buf[100];
822 
823 	for (f = Files; f != NULL; f = f->f_next) {
824 		/* flush any pending output */
825 		if (f->f_prevcount)
826 			fprintlog(f, 0, (char *)NULL);
827 	}
828 	if (signo) {
829 		dprintf("syslogd: exiting on signal %d\n", signo);
830 		(void)sprintf(buf, "exiting on signal %d", signo);
831 		errno = 0;
832 		logerror(buf);
833 	}
834 	(void)unlink(LogName);
835 	exit(0);
836 }
837 
838 /*
839  *  INIT -- Initialize syslogd from configuration table
840  */
841 void
842 init(signo)
843 	int signo;
844 {
845 	register int i;
846 	register FILE *cf;
847 	register struct filed *f, *next, **nextp;
848 	register char *p;
849 	char cline[BUFSIZ];
850 
851 	dprintf("init\n");
852 
853 	/*
854 	 *  Close all open log files.
855 	 */
856 	Initialized = 0;
857 	for (f = Files; f != NULL; f = next) {
858 		/* flush any pending output */
859 		if (f->f_prevcount)
860 			fprintlog(f, 0, (char *)NULL);
861 
862 		switch (f->f_type) {
863 		case F_FILE:
864 		case F_TTY:
865 		case F_CONSOLE:
866 		case F_FORW:
867 			(void)close(f->f_file);
868 			break;
869 		}
870 		next = f->f_next;
871 		free((char *)f);
872 	}
873 	Files = NULL;
874 	nextp = &Files;
875 
876 	/* open the configuration file */
877 	if ((cf = fopen(ConfFile, "r")) == NULL) {
878 		dprintf("cannot open %s\n", ConfFile);
879 		*nextp = (struct filed *)calloc(1, sizeof(*f));
880 		cfline("*.ERR\t/dev/console", *nextp);
881 		(*nextp)->f_next = (struct filed *)calloc(1, sizeof(*f));
882 		cfline("*.PANIC\t*", (*nextp)->f_next);
883 		Initialized = 1;
884 		return;
885 	}
886 
887 	/*
888 	 *  Foreach line in the conf table, open that file.
889 	 */
890 	f = NULL;
891 	while (fgets(cline, sizeof cline, cf) != NULL) {
892 		/*
893 		 * check for end-of-section, comments, strip off trailing
894 		 * spaces and newline character.
895 		 */
896 		for (p = cline; isspace(*p); ++p);
897 		if (*p == NULL || *p == '#')
898 			continue;
899 		for (p = index(cline, '\0'); isspace(*--p););
900 		*++p = '\0';
901 		f = (struct filed *)calloc(1, sizeof(*f));
902 		*nextp = f;
903 		nextp = &f->f_next;
904 		cfline(cline, f);
905 	}
906 
907 	/* close the configuration file */
908 	(void)fclose(cf);
909 
910 	Initialized = 1;
911 
912 	if (Debug) {
913 		for (f = Files; f; f = f->f_next) {
914 			for (i = 0; i <= LOG_NFACILITIES; i++)
915 				if (f->f_pmask[i] == INTERNAL_NOPRI)
916 					printf("X ");
917 				else
918 					printf("%d ", f->f_pmask[i]);
919 			printf("%s: ", TypeNames[f->f_type]);
920 			switch (f->f_type) {
921 			case F_FILE:
922 			case F_TTY:
923 			case F_CONSOLE:
924 				printf("%s", f->f_un.f_fname);
925 				break;
926 
927 			case F_FORW:
928 				printf("%s", f->f_un.f_forw.f_hname);
929 				break;
930 
931 			case F_USERS:
932 				for (i = 0; i < MAXUNAMES && *f->f_un.f_uname[i]; i++)
933 					printf("%s, ", f->f_un.f_uname[i]);
934 				break;
935 			}
936 			printf("\n");
937 		}
938 	}
939 
940 	logmsg(LOG_SYSLOG|LOG_INFO, "syslogd: restart", LocalHostName, ADDDATE);
941 	dprintf("syslogd: restarted\n");
942 }
943 
944 /*
945  * Crack a configuration file line
946  */
947 void
948 cfline(line, f)
949 	char *line;
950 	register struct filed *f;
951 {
952 	register char *p;
953 	register char *q;
954 	register int i;
955 	char *bp;
956 	int pri;
957 	struct hostent *hp;
958 	char buf[MAXLINE], ebuf[100];
959 
960 	dprintf("cfline(%s)\n", line);
961 
962 	errno = 0;	/* keep strerror() stuff out of logerror messages */
963 
964 	/* clear out file entry */
965 	bzero((char *)f, sizeof *f);
966 	for (i = 0; i <= LOG_NFACILITIES; i++)
967 		f->f_pmask[i] = INTERNAL_NOPRI;
968 
969 	/* scan through the list of selectors */
970 	for (p = line; *p && *p != '\t';) {
971 
972 		/* find the end of this facility name list */
973 		for (q = p; *q && *q != '\t' && *q++ != '.'; )
974 			continue;
975 
976 		/* collect priority name */
977 		for (bp = buf; *q && !index("\t,;", *q); )
978 			*bp++ = *q++;
979 		*bp = '\0';
980 
981 		/* skip cruft */
982 		while (index(", ;", *q))
983 			q++;
984 
985 		/* decode priority name */
986 		if (*buf == '*')
987 			pri = LOG_PRIMASK + 1;
988 		else {
989 			pri = decode(buf, prioritynames);
990 			if (pri < 0) {
991 				(void)sprintf(ebuf,
992 				    "unknown priority name \"%s\"", buf);
993 				logerror(ebuf);
994 				return;
995 			}
996 		}
997 
998 		/* scan facilities */
999 		while (*p && !index("\t.;", *p)) {
1000 			for (bp = buf; *p && !index("\t,;.", *p); )
1001 				*bp++ = *p++;
1002 			*bp = '\0';
1003 			if (*buf == '*')
1004 				for (i = 0; i < LOG_NFACILITIES; i++)
1005 					f->f_pmask[i] = pri;
1006 			else {
1007 				i = decode(buf, facilitynames);
1008 				if (i < 0) {
1009 					(void)sprintf(ebuf,
1010 					    "unknown facility name \"%s\"",
1011 					    buf);
1012 					logerror(ebuf);
1013 					return;
1014 				}
1015 				f->f_pmask[i >> 3] = pri;
1016 			}
1017 			while (*p == ',' || *p == ' ')
1018 				p++;
1019 		}
1020 
1021 		p = q;
1022 	}
1023 
1024 	/* skip to action part */
1025 	while (*p == '\t')
1026 		p++;
1027 
1028 	switch (*p)
1029 	{
1030 	case '@':
1031 		if (!InetInuse)
1032 			break;
1033 		(void)strcpy(f->f_un.f_forw.f_hname, ++p);
1034 		hp = gethostbyname(p);
1035 		if (hp == NULL) {
1036 			extern int h_errno, h_nerr;
1037 			extern char *h_errlist[];
1038 
1039 			logerror((u_int)h_errno < h_nerr ?
1040 			    h_errlist[h_errno] : "Unknown error");
1041 			break;
1042 		}
1043 		bzero((char *)&f->f_un.f_forw.f_addr,
1044 			 sizeof f->f_un.f_forw.f_addr);
1045 		f->f_un.f_forw.f_addr.sin_family = AF_INET;
1046 		f->f_un.f_forw.f_addr.sin_port = LogPort;
1047 		bcopy(hp->h_addr, (char *)&f->f_un.f_forw.f_addr.sin_addr, hp->h_length);
1048 		f->f_type = F_FORW;
1049 		break;
1050 
1051 	case '/':
1052 		(void)strcpy(f->f_un.f_fname, p);
1053 		if ((f->f_file = open(p, O_WRONLY|O_APPEND, 0)) < 0) {
1054 			f->f_file = F_UNUSED;
1055 			logerror(p);
1056 			break;
1057 		}
1058 		if (isatty(f->f_file))
1059 			f->f_type = F_TTY;
1060 		else
1061 			f->f_type = F_FILE;
1062 		if (strcmp(p, ctty) == 0)
1063 			f->f_type = F_CONSOLE;
1064 		break;
1065 
1066 	case '*':
1067 		f->f_type = F_WALL;
1068 		break;
1069 
1070 	default:
1071 		for (i = 0; i < MAXUNAMES && *p; i++) {
1072 			for (q = p; *q && *q != ','; )
1073 				q++;
1074 			(void)strncpy(f->f_un.f_uname[i], p, UT_NAMESIZE);
1075 			if ((q - p) > UT_NAMESIZE)
1076 				f->f_un.f_uname[i][UT_NAMESIZE] = '\0';
1077 			else
1078 				f->f_un.f_uname[i][q - p] = '\0';
1079 			while (*q == ',' || *q == ' ')
1080 				q++;
1081 			p = q;
1082 		}
1083 		f->f_type = F_USERS;
1084 		break;
1085 	}
1086 }
1087 
1088 
1089 /*
1090  *  Decode a symbolic name to a numeric value
1091  */
1092 int
1093 decode(name, codetab)
1094 	const char *name;
1095 	CODE *codetab;
1096 {
1097 	register CODE *c;
1098 	register char *p;
1099 	char buf[40];
1100 
1101 	if (isdigit(*name))
1102 		return (atoi(name));
1103 
1104 	for (p = buf; *name && p < &buf[sizeof(buf) - 1]; p++, name++) {
1105 		if (isupper(*name))
1106 			*p = tolower(*name);
1107 		else
1108 			*p = *name;
1109 	}
1110 	*p = '\0';
1111 	for (c = codetab; c->c_name; c++)
1112 		if (!strcmp(buf, c->c_name))
1113 			return (c->c_val);
1114 
1115 	return (-1);
1116 }
1117