xref: /netbsd-src/usr.sbin/syslogd/syslogd.c (revision 61f282557f0bc41c0b762c629a2f4c14be8b7591)
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[] = "@(#)syslogd.c	5.45 (Berkeley) 3/2/91";
42 #endif /* not lint */
43 
44 /*
45  *  syslogd -- log system messages
46  *
47  * This program implements a system log. It takes a series of lines.
48  * Each line may have a priority, signified as "<n>" as
49  * the first characters of the line.  If this is
50  * not present, a default priority is used.
51  *
52  * To kill syslogd, send a signal 15 (terminate).  A signal 1 (hup) will
53  * cause it to reread its configuration file.
54  *
55  * Defined Constants:
56  *
57  * MAXLINE -- the maximimum line length that can be handled.
58  * DEFUPRI -- the default priority for user messages
59  * DEFSPRI -- the default priority for kernel messages
60  *
61  * Author: Eric Allman
62  * extensive changes by Ralph Campbell
63  * more extensive changes by Eric Allman (again)
64  */
65 
66 #define	MAXLINE		1024		/* maximum line length */
67 #define	MAXSVLINE	120		/* maximum saved line length */
68 #define DEFUPRI		(LOG_USER|LOG_NOTICE)
69 #define DEFSPRI		(LOG_KERN|LOG_CRIT)
70 #define TIMERINTVL	30		/* interval for checking flush, mark */
71 
72 #include <sys/param.h>
73 #include <sys/errno.h>
74 #include <sys/ioctl.h>
75 #include <sys/stat.h>
76 #include <sys/wait.h>
77 #include <sys/socket.h>
78 #include <sys/file.h>
79 #include <sys/msgbuf.h>
80 #include <sys/uio.h>
81 #include <sys/un.h>
82 #include <sys/time.h>
83 #include <sys/resource.h>
84 #include <sys/signal.h>
85 
86 #include <netinet/in.h>
87 #include <netdb.h>
88 
89 #include <utmp.h>
90 #include <setjmp.h>
91 #include <stdio.h>
92 #include <ctype.h>
93 #include <string.h>
94 #include <unistd.h>
95 #include "pathnames.h"
96 
97 #define SYSLOG_NAMES
98 #include <sys/syslog.h>
99 
100 char	*LogName = _PATH_LOG;
101 char	*ConfFile = _PATH_LOGCONF;
102 char	*PidFile = _PATH_LOGPID;
103 char	ctty[] = _PATH_CONSOLE;
104 
105 #define FDMASK(fd)	(1 << (fd))
106 
107 #define	dprintf		if (Debug) printf
108 
109 #define MAXUNAMES	20	/* maximum number of user names */
110 
111 /*
112  * Flags to logmsg().
113  */
114 
115 #define IGN_CONS	0x001	/* don't print on console */
116 #define SYNC_FILE	0x002	/* do fsync on file after printing */
117 #define ADDDATE		0x004	/* add a date to the message */
118 #define MARK		0x008	/* this message is a mark */
119 
120 /*
121  * This structure represents the files that will have log
122  * copies printed.
123  */
124 
125 struct filed {
126 	struct	filed *f_next;		/* next in linked list */
127 	short	f_type;			/* entry type, see below */
128 	short	f_file;			/* file descriptor */
129 	time_t	f_time;			/* time this was last written */
130 	u_char	f_pmask[LOG_NFACILITIES+1];	/* priority mask */
131 	union {
132 		char	f_uname[MAXUNAMES][UT_NAMESIZE+1];
133 		struct {
134 			char	f_hname[MAXHOSTNAMELEN+1];
135 			struct sockaddr_in	f_addr;
136 		} f_forw;		/* forwarding address */
137 		char	f_fname[MAXPATHLEN];
138 	} f_un;
139 	char	f_prevline[MAXSVLINE];		/* last message logged */
140 	char	f_lasttime[16];			/* time of last occurrence */
141 	char	f_prevhost[MAXHOSTNAMELEN+1];	/* host from which recd. */
142 	int	f_prevpri;			/* pri of f_prevline */
143 	int	f_prevlen;			/* length of f_prevline */
144 	int	f_prevcount;			/* repetition cnt of prevline */
145 	int	f_repeatcount;			/* number of "repeated" msgs */
146 };
147 
148 /*
149  * Intervals at which we flush out "message repeated" messages,
150  * in seconds after previous message is logged.  After each flush,
151  * we move to the next interval until we reach the largest.
152  */
153 int	repeatinterval[] = { 30, 120, 600 };	/* # of secs before flush */
154 #define	MAXREPEAT ((sizeof(repeatinterval) / sizeof(repeatinterval[0])) - 1)
155 #define	REPEATTIME(f)	((f)->f_time + repeatinterval[(f)->f_repeatcount])
156 #define	BACKOFF(f)	{ if (++(f)->f_repeatcount > MAXREPEAT) \
157 				 (f)->f_repeatcount = MAXREPEAT; \
158 			}
159 
160 /* values for f_type */
161 #define F_UNUSED	0		/* unused entry */
162 #define F_FILE		1		/* regular file */
163 #define F_TTY		2		/* terminal */
164 #define F_CONSOLE	3		/* console terminal */
165 #define F_FORW		4		/* remote machine */
166 #define F_USERS		5		/* list of users */
167 #define F_WALL		6		/* everyone logged on */
168 
169 char	*TypeNames[7] = {
170 	"UNUSED",	"FILE",		"TTY",		"CONSOLE",
171 	"FORW",		"USERS",	"WALL"
172 };
173 
174 struct	filed *Files;
175 struct	filed consfile;
176 
177 int	Debug;			/* debug flag */
178 char	LocalHostName[MAXHOSTNAMELEN+1];	/* our hostname */
179 char	*LocalDomain;		/* our local domain name */
180 int	InetInuse = 0;		/* non-zero if INET sockets are being used */
181 int	finet;			/* Internet datagram socket */
182 int	LogPort;		/* port number for INET connections */
183 int	Initialized = 0;	/* set when we have initialized ourselves */
184 int	MarkInterval = 20 * 60;	/* interval between marks in seconds */
185 int	MarkSeq = 0;		/* mark sequence number */
186 
187 extern	int errno;
188 extern	char *ctime(), *index(), *calloc();
189 
190 main(argc, argv)
191 	int argc;
192 	char **argv;
193 {
194 	register int i;
195 	register char *p;
196 	int funix, inetm, fklog, klogm, len;
197 	struct sockaddr_un sunx, fromunix;
198 	struct sockaddr_in sin, frominet;
199 	FILE *fp;
200 	int ch;
201 	char line[MSG_BSIZE + 1];
202 	extern int optind;
203 	extern char *optarg;
204 	void die(), domark(), init(), reapchild();
205 
206 	while ((ch = getopt(argc, argv, "df:m:p:")) != EOF)
207 		switch((char)ch) {
208 		case 'd':		/* debug */
209 			Debug++;
210 			break;
211 		case 'f':		/* configuration file */
212 			ConfFile = optarg;
213 			break;
214 		case 'm':		/* mark interval */
215 			MarkInterval = atoi(optarg) * 60;
216 			break;
217 		case 'p':		/* path */
218 			LogName = optarg;
219 			break;
220 		case '?':
221 		default:
222 			usage();
223 		}
224 	if (argc -= optind)
225 		usage();
226 
227 	if (!Debug)
228 		daemon(0, 0);
229 	else
230 		setlinebuf(stdout);
231 
232 	consfile.f_type = F_CONSOLE;
233 	(void) strcpy(consfile.f_un.f_fname, ctty);
234 	(void) gethostname(LocalHostName, sizeof LocalHostName);
235 	if (p = index(LocalHostName, '.')) {
236 		*p++ = '\0';
237 		LocalDomain = p;
238 	}
239 	else
240 		LocalDomain = "";
241 	(void) signal(SIGTERM, die);
242 	(void) signal(SIGINT, Debug ? die : SIG_IGN);
243 	(void) signal(SIGQUIT, Debug ? die : SIG_IGN);
244 	(void) signal(SIGCHLD, reapchild);
245 	(void) signal(SIGALRM, domark);
246 	(void) alarm(TIMERINTVL);
247 	(void) unlink(LogName);
248 
249 	bzero((char *)&sunx, sizeof(sunx));
250 	sunx.sun_family = AF_UNIX;
251 	(void) strncpy(sunx.sun_path, LogName, sizeof sunx.sun_path);
252 	funix = socket(AF_UNIX, SOCK_DGRAM, 0);
253 	if (funix < 0 || bind(funix, (struct sockaddr *) &sunx,
254 	    sizeof(sunx.sun_family)+sizeof(sunx.sun_len)+
255 	    strlen(sunx.sun_path)) < 0 ||
256 	    chmod(LogName, 0666) < 0) {
257 		(void) sprintf(line, "cannot create %s", LogName);
258 		logerror(line);
259 		dprintf("cannot create %s (%d)\n", LogName, errno);
260 		die(0);
261 	}
262 	finet = socket(AF_INET, SOCK_DGRAM, 0);
263 	if (finet >= 0) {
264 		struct servent *sp;
265 
266 		sp = getservbyname("syslog", "udp");
267 		if (sp == NULL) {
268 			errno = 0;
269 			logerror("syslog/udp: unknown service");
270 			die(0);
271 		}
272 		bzero((char *)&sin, sizeof(sin));
273 		sin.sin_family = AF_INET;
274 		sin.sin_port = LogPort = sp->s_port;
275 		if (bind(finet, (struct sockaddr *)&sin, sizeof(sin)) < 0) {
276 			logerror("bind");
277 			if (!Debug)
278 				die(0);
279 		} else {
280 			inetm = FDMASK(finet);
281 			InetInuse = 1;
282 		}
283 	}
284 	if ((fklog = open(_PATH_KLOG, O_RDONLY, 0)) >= 0)
285 		klogm = FDMASK(fklog);
286 	else {
287 		dprintf("can't open %s (%d)\n", _PATH_KLOG, errno);
288 		klogm = 0;
289 	}
290 
291 	/* tuck my process id away */
292 	fp = fopen(PidFile, "w");
293 	if (fp != NULL) {
294 		fprintf(fp, "%d\n", getpid());
295 		(void) fclose(fp);
296 	}
297 
298 	dprintf("off & running....\n");
299 
300 	init();
301 	(void) signal(SIGHUP, init);
302 
303 	for (;;) {
304 		int nfds, readfds = FDMASK(funix) | inetm | klogm;
305 
306 		errno = 0;
307 		dprintf("readfds = %#x\n", readfds);
308 		nfds = select(20, (fd_set *) &readfds, (fd_set *) NULL,
309 		    (fd_set *) NULL, (struct timeval *) NULL);
310 		if (nfds == 0)
311 			continue;
312 		if (nfds < 0) {
313 			if (errno != EINTR)
314 				logerror("select");
315 			continue;
316 		}
317 		dprintf("got a message (%d, %#x)\n", nfds, readfds);
318 		if (readfds & klogm) {
319 			i = read(fklog, line, sizeof(line) - 1);
320 			if (i > 0) {
321 				line[i] = '\0';
322 				printsys(line);
323 			} else if (i < 0 && errno != EINTR) {
324 				logerror("klog");
325 				fklog = -1;
326 				klogm = 0;
327 			}
328 		}
329 		if (readfds & FDMASK(funix)) {
330 			len = sizeof fromunix;
331 			i = recvfrom(funix, line, MAXLINE, 0,
332 			    (struct sockaddr *) &fromunix, &len);
333 			if (i > 0) {
334 				line[i] = '\0';
335 				printline(LocalHostName, line);
336 			} else if (i < 0 && errno != EINTR)
337 				logerror("recvfrom unix");
338 		}
339 		if (readfds & inetm) {
340 			len = sizeof frominet;
341 			i = recvfrom(finet, line, MAXLINE, 0,
342 			    (struct sockaddr *) &frominet, &len);
343 			if (i > 0) {
344 				extern char *cvthname();
345 
346 				line[i] = '\0';
347 				printline(cvthname(&frominet), line);
348 			} else if (i < 0 && errno != EINTR)
349 				logerror("recvfrom inet");
350 		}
351 	}
352 }
353 
354 usage()
355 {
356 	(void) fprintf(stderr,
357 	    "usage: syslogd [-f conffile] [-m markinterval] [-p logpath]\n");
358 	exit(1);
359 }
360 
361 /*
362  * Take a raw input line, decode the message, and print the message
363  * on the appropriate log files.
364  */
365 
366 printline(hname, msg)
367 	char *hname;
368 	char *msg;
369 {
370 	register char *p, *q;
371 	register int c;
372 	char line[MAXLINE + 1];
373 	int pri;
374 
375 	/* test for special codes */
376 	pri = DEFUPRI;
377 	p = msg;
378 	if (*p == '<') {
379 		pri = 0;
380 		while (isdigit(*++p))
381 			pri = 10 * pri + (*p - '0');
382 		if (*p == '>')
383 			++p;
384 	}
385 	if (pri &~ (LOG_FACMASK|LOG_PRIMASK))
386 		pri = DEFUPRI;
387 
388 	/* don't allow users to log kernel messages */
389 	if (LOG_FAC(pri) == LOG_KERN)
390 		pri = LOG_MAKEPRI(LOG_USER, LOG_PRI(pri));
391 
392 	q = line;
393 
394 	while ((c = *p++ & 0177) != '\0' &&
395 	    q < &line[sizeof(line) - 1])
396 		if (iscntrl(c))
397 			if (c == '\n')
398 				*q++ = ' ';
399 			else if (c == '\t')
400 				*q++ = '\t';
401 			else {
402 				*q++ = '^';
403 				*q++ = c ^ 0100;
404 			}
405 		else
406 			*q++ = c;
407 	*q = '\0';
408 
409 	logmsg(pri, line, hname, 0);
410 }
411 
412 /*
413  * Take a raw input line from /dev/klog, split and format similar to syslog().
414  */
415 
416 printsys(msg)
417 	char *msg;
418 {
419 	register char *p, *q;
420 	register int c;
421 	char line[MAXLINE + 1];
422 	int pri, flags;
423 	char *lp;
424 
425 	(void) strcpy(line, _PATH_UNIX);
426 	(void) strcat(line, ": ");
427 	lp = line + strlen(line);
428 	for (p = msg; *p != '\0'; ) {
429 		flags = SYNC_FILE | ADDDATE;	/* fsync file after write */
430 		pri = DEFSPRI;
431 		if (*p == '<') {
432 			pri = 0;
433 			while (isdigit(*++p))
434 				pri = 10 * pri + (*p - '0');
435 			if (*p == '>')
436 				++p;
437 		} else {
438 			/* kernel printf's come out on console */
439 			flags |= IGN_CONS;
440 		}
441 		if (pri &~ (LOG_FACMASK|LOG_PRIMASK))
442 			pri = DEFSPRI;
443 		q = lp;
444 		while (*p != '\0' && (c = *p++) != '\n' &&
445 		    q < &line[MAXLINE])
446 			*q++ = c;
447 		*q = '\0';
448 		logmsg(pri, line, LocalHostName, flags);
449 	}
450 }
451 
452 time_t	now;
453 
454 /*
455  * Log a message to the appropriate log files, users, etc. based on
456  * the priority.
457  */
458 
459 logmsg(pri, msg, from, flags)
460 	int pri;
461 	char *msg, *from;
462 	int flags;
463 {
464 	register struct filed *f;
465 	int fac, prilev;
466 	int omask, msglen;
467 	char *timestamp;
468 	time_t time();
469 
470 	dprintf("logmsg: pri %o, flags %x, from %s, msg %s\n",
471 	    pri, flags, from, msg);
472 
473 	omask = sigblock(sigmask(SIGHUP)|sigmask(SIGALRM));
474 
475 	/*
476 	 * Check to see if msg looks non-standard.
477 	 */
478 	msglen = strlen(msg);
479 	if (msglen < 16 || msg[3] != ' ' || msg[6] != ' ' ||
480 	    msg[9] != ':' || msg[12] != ':' || msg[15] != ' ')
481 		flags |= ADDDATE;
482 
483 	(void) time(&now);
484 	if (flags & ADDDATE)
485 		timestamp = ctime(&now) + 4;
486 	else {
487 		timestamp = msg;
488 		msg += 16;
489 		msglen -= 16;
490 	}
491 
492 	/* extract facility and priority level */
493 	if (flags & MARK)
494 		fac = LOG_NFACILITIES;
495 	else
496 		fac = LOG_FAC(pri);
497 	prilev = LOG_PRI(pri);
498 
499 	/* log the message to the particular outputs */
500 	if (!Initialized) {
501 		f = &consfile;
502 		f->f_file = open(ctty, O_WRONLY, 0);
503 
504 		if (f->f_file >= 0) {
505 			fprintlog(f, flags, msg);
506 			(void) close(f->f_file);
507 		}
508 		(void) sigsetmask(omask);
509 		return;
510 	}
511 	for (f = Files; f; f = f->f_next) {
512 		/* skip messages that are incorrect priority */
513 		if (f->f_pmask[fac] < prilev ||
514 		    f->f_pmask[fac] == INTERNAL_NOPRI)
515 			continue;
516 
517 		if (f->f_type == F_CONSOLE && (flags & IGN_CONS))
518 			continue;
519 
520 		/* don't output marks to recently written files */
521 		if ((flags & MARK) && (now - f->f_time) < MarkInterval / 2)
522 			continue;
523 
524 		/*
525 		 * suppress duplicate lines to this file
526 		 */
527 		if ((flags & MARK) == 0 && msglen == f->f_prevlen &&
528 		    !strcmp(msg, f->f_prevline) &&
529 		    !strcmp(from, f->f_prevhost)) {
530 			(void) strncpy(f->f_lasttime, timestamp, 15);
531 			f->f_prevcount++;
532 			dprintf("msg repeated %d times, %ld sec of %d\n",
533 			    f->f_prevcount, now - f->f_time,
534 			    repeatinterval[f->f_repeatcount]);
535 			/*
536 			 * If domark would have logged this by now,
537 			 * flush it now (so we don't hold isolated messages),
538 			 * but back off so we'll flush less often
539 			 * in the future.
540 			 */
541 			if (now > REPEATTIME(f)) {
542 				fprintlog(f, flags, (char *)NULL);
543 				BACKOFF(f);
544 			}
545 		} else {
546 			/* new line, save it */
547 			if (f->f_prevcount)
548 				fprintlog(f, 0, (char *)NULL);
549 			f->f_repeatcount = 0;
550 			(void) strncpy(f->f_lasttime, timestamp, 15);
551 			(void) strncpy(f->f_prevhost, from,
552 					sizeof(f->f_prevhost));
553 			if (msglen < MAXSVLINE) {
554 				f->f_prevlen = msglen;
555 				f->f_prevpri = pri;
556 				(void) strcpy(f->f_prevline, msg);
557 				fprintlog(f, flags, (char *)NULL);
558 			} else {
559 				f->f_prevline[0] = 0;
560 				f->f_prevlen = 0;
561 				fprintlog(f, flags, msg);
562 			}
563 		}
564 	}
565 	(void) sigsetmask(omask);
566 }
567 
568 fprintlog(f, flags, msg)
569 	register struct filed *f;
570 	int flags;
571 	char *msg;
572 {
573 	struct iovec iov[6];
574 	register struct iovec *v;
575 	register int l;
576 	char line[MAXLINE + 1], repbuf[80], greetings[200];
577 
578 	v = iov;
579 	if (f->f_type == F_WALL) {
580 		v->iov_base = greetings;
581 		v->iov_len = sprintf(greetings,
582 		    "\r\n\7Message from syslogd@%s at %.24s ...\r\n",
583 		    f->f_prevhost, ctime(&now));
584 		v++;
585 		v->iov_base = "";
586 		v->iov_len = 0;
587 		v++;
588 	} else {
589 		v->iov_base = f->f_lasttime;
590 		v->iov_len = 15;
591 		v++;
592 		v->iov_base = " ";
593 		v->iov_len = 1;
594 		v++;
595 	}
596 	v->iov_base = f->f_prevhost;
597 	v->iov_len = strlen(v->iov_base);
598 	v++;
599 	v->iov_base = " ";
600 	v->iov_len = 1;
601 	v++;
602 
603 	if (msg) {
604 		v->iov_base = msg;
605 		v->iov_len = strlen(msg);
606 	} else if (f->f_prevcount > 1) {
607 		v->iov_base = repbuf;
608 		v->iov_len = sprintf(repbuf, "last message repeated %d times",
609 		    f->f_prevcount);
610 	} else {
611 		v->iov_base = f->f_prevline;
612 		v->iov_len = f->f_prevlen;
613 	}
614 	v++;
615 
616 	dprintf("Logging to %s", TypeNames[f->f_type]);
617 	f->f_time = now;
618 
619 	switch (f->f_type) {
620 	case F_UNUSED:
621 		dprintf("\n");
622 		break;
623 
624 	case F_FORW:
625 		dprintf(" %s\n", f->f_un.f_forw.f_hname);
626 		l = sprintf(line, "<%d>%.15s %s", f->f_prevpri,
627 		    iov[0].iov_base, iov[4].iov_base);
628 		if (l > MAXLINE)
629 			l = MAXLINE;
630 		if (sendto(finet, line, l, 0,
631 		    (struct sockaddr *)&f->f_un.f_forw.f_addr,
632 		    sizeof f->f_un.f_forw.f_addr) != l) {
633 			int e = errno;
634 			(void) close(f->f_file);
635 			f->f_type = F_UNUSED;
636 			errno = e;
637 			logerror("sendto");
638 		}
639 		break;
640 
641 	case F_CONSOLE:
642 		if (flags & IGN_CONS) {
643 			dprintf(" (ignored)\n");
644 			break;
645 		}
646 		/* FALLTHROUGH */
647 
648 	case F_TTY:
649 	case F_FILE:
650 		dprintf(" %s\n", f->f_un.f_fname);
651 		if (f->f_type != F_FILE) {
652 			v->iov_base = "\r\n";
653 			v->iov_len = 2;
654 		} else {
655 			v->iov_base = "\n";
656 			v->iov_len = 1;
657 		}
658 	again:
659 		if (writev(f->f_file, iov, 6) < 0) {
660 			int e = errno;
661 			(void) close(f->f_file);
662 			/*
663 			 * Check for errors on TTY's due to loss of tty
664 			 */
665 			if ((e == EIO || e == EBADF) && f->f_type != F_FILE) {
666 				f->f_file = open(f->f_un.f_fname,
667 				    O_WRONLY|O_APPEND, 0);
668 				if (f->f_file < 0) {
669 					f->f_type = F_UNUSED;
670 					logerror(f->f_un.f_fname);
671 				} else
672 					goto again;
673 			} else {
674 				f->f_type = F_UNUSED;
675 				errno = e;
676 				logerror(f->f_un.f_fname);
677 			}
678 		} else if (flags & SYNC_FILE)
679 			(void) fsync(f->f_file);
680 		break;
681 
682 	case F_USERS:
683 	case F_WALL:
684 		dprintf("\n");
685 		v->iov_base = "\r\n";
686 		v->iov_len = 2;
687 		wallmsg(f, iov);
688 		break;
689 	}
690 	f->f_prevcount = 0;
691 }
692 
693 /*
694  *  WALLMSG -- Write a message to the world at large
695  *
696  *	Write the specified message to either the entire
697  *	world, or a list of approved users.
698  */
699 
700 wallmsg(f, iov)
701 	register struct filed *f;
702 	struct iovec *iov;
703 {
704 	static int reenter;			/* avoid calling ourselves */
705 	register FILE *uf;
706 	register int i;
707 	struct utmp ut;
708 	char *p, *ttymsg();
709 
710 	if (reenter++)
711 		return;
712 	if ((uf = fopen(_PATH_UTMP, "r")) == NULL) {
713 		logerror(_PATH_UTMP);
714 		reenter = 0;
715 		return;
716 	}
717 	/* NOSTRICT */
718 	while (fread((char *) &ut, sizeof ut, 1, uf) == 1) {
719 		if (ut.ut_name[0] == '\0')
720 			continue;
721 		if (f->f_type == F_WALL) {
722 			if (p = ttymsg(iov, 6, ut.ut_line, 1)) {
723 				errno = 0;	/* already in msg */
724 				logerror(p);
725 			}
726 			continue;
727 		}
728 		/* should we send the message to this user? */
729 		for (i = 0; i < MAXUNAMES; i++) {
730 			if (!f->f_un.f_uname[i][0])
731 				break;
732 			if (!strncmp(f->f_un.f_uname[i], ut.ut_name,
733 			    UT_NAMESIZE)) {
734 				if (p = ttymsg(iov, 6, ut.ut_line, 1)) {
735 					errno = 0;	/* already in msg */
736 					logerror(p);
737 				}
738 				break;
739 			}
740 		}
741 	}
742 	(void) fclose(uf);
743 	reenter = 0;
744 }
745 
746 void
747 reapchild()
748 {
749 	union wait status;
750 
751 	while (wait3((int *)&status, WNOHANG, (struct rusage *) NULL) > 0)
752 		;
753 }
754 
755 /*
756  * Return a printable representation of a host address.
757  */
758 char *
759 cvthname(f)
760 	struct sockaddr_in *f;
761 {
762 	struct hostent *hp;
763 	register char *p;
764 	extern char *inet_ntoa();
765 
766 	dprintf("cvthname(%s)\n", inet_ntoa(f->sin_addr));
767 
768 	if (f->sin_family != AF_INET) {
769 		dprintf("Malformed from address\n");
770 		return ("???");
771 	}
772 	hp = gethostbyaddr((char *)&f->sin_addr,
773 	    sizeof(struct in_addr), f->sin_family);
774 	if (hp == 0) {
775 		dprintf("Host name for your address (%s) unknown\n",
776 			inet_ntoa(f->sin_addr));
777 		return (inet_ntoa(f->sin_addr));
778 	}
779 	if ((p = index(hp->h_name, '.')) && strcmp(p + 1, LocalDomain) == 0)
780 		*p = '\0';
781 	return (hp->h_name);
782 }
783 
784 void
785 domark()
786 {
787 	register struct filed *f;
788 	time_t time();
789 
790 	now = time((time_t *)NULL);
791 	MarkSeq += TIMERINTVL;
792 	if (MarkSeq >= MarkInterval) {
793 		logmsg(LOG_INFO, "-- MARK --", LocalHostName, ADDDATE|MARK);
794 		MarkSeq = 0;
795 	}
796 
797 	for (f = Files; f; f = f->f_next) {
798 		if (f->f_prevcount && now >= REPEATTIME(f)) {
799 			dprintf("flush %s: repeated %d times, %d sec.\n",
800 			    TypeNames[f->f_type], f->f_prevcount,
801 			    repeatinterval[f->f_repeatcount]);
802 			fprintlog(f, 0, (char *)NULL);
803 			BACKOFF(f);
804 		}
805 	}
806 	(void) alarm(TIMERINTVL);
807 }
808 
809 /*
810  * Print syslogd errors some place.
811  */
812 logerror(type)
813 	char *type;
814 {
815 	char buf[100], *strerror();
816 
817 	if (errno)
818 		(void) sprintf(buf, "syslogd: %s: %s", type, strerror(errno));
819 	else
820 		(void) sprintf(buf, "syslogd: %s", type);
821 	errno = 0;
822 	dprintf("%s\n", buf);
823 	logmsg(LOG_SYSLOG|LOG_ERR, buf, LocalHostName, ADDDATE);
824 }
825 
826 void
827 die(sig)
828 {
829 	register struct filed *f;
830 	char buf[100];
831 
832 	for (f = Files; f != NULL; f = f->f_next) {
833 		/* flush any pending output */
834 		if (f->f_prevcount)
835 			fprintlog(f, 0, (char *)NULL);
836 	}
837 	if (sig) {
838 		dprintf("syslogd: exiting on signal %d\n", sig);
839 		(void) sprintf(buf, "exiting on signal %d", sig);
840 		errno = 0;
841 		logerror(buf);
842 	}
843 	(void) unlink(LogName);
844 	exit(0);
845 }
846 
847 /*
848  *  INIT -- Initialize syslogd from configuration table
849  */
850 
851 void
852 init()
853 {
854 	register int i;
855 	register FILE *cf;
856 	register struct filed *f, *next, **nextp;
857 	register char *p;
858 	char cline[BUFSIZ];
859 
860 	dprintf("init\n");
861 
862 	/*
863 	 *  Close all open log files.
864 	 */
865 	Initialized = 0;
866 	for (f = Files; f != NULL; f = next) {
867 		/* flush any pending output */
868 		if (f->f_prevcount)
869 			fprintlog(f, 0, (char *)NULL);
870 
871 		switch (f->f_type) {
872 		  case F_FILE:
873 		  case F_TTY:
874 		  case F_CONSOLE:
875 		  case F_FORW:
876 			(void) close(f->f_file);
877 			break;
878 		}
879 		next = f->f_next;
880 		free((char *) f);
881 	}
882 	Files = NULL;
883 	nextp = &Files;
884 
885 	/* open the configuration file */
886 	if ((cf = fopen(ConfFile, "r")) == NULL) {
887 		dprintf("cannot open %s\n", ConfFile);
888 		*nextp = (struct filed *)calloc(1, sizeof(*f));
889 		cfline("*.ERR\t/dev/console", *nextp);
890 		(*nextp)->f_next = (struct filed *)calloc(1, sizeof(*f));
891 		cfline("*.PANIC\t*", (*nextp)->f_next);
892 		Initialized = 1;
893 		return;
894 	}
895 
896 	/*
897 	 *  Foreach line in the conf table, open that file.
898 	 */
899 	f = NULL;
900 	while (fgets(cline, sizeof cline, cf) != NULL) {
901 		/*
902 		 * check for end-of-section, comments, strip off trailing
903 		 * spaces and newline character.
904 		 */
905 		for (p = cline; isspace(*p); ++p);
906 		if (*p == NULL || *p == '#')
907 			continue;
908 		for (p = index(cline, '\0'); isspace(*--p););
909 		*++p = '\0';
910 		f = (struct filed *)calloc(1, sizeof(*f));
911 		*nextp = f;
912 		nextp = &f->f_next;
913 		cfline(cline, f);
914 	}
915 
916 	/* close the configuration file */
917 	(void) fclose(cf);
918 
919 	Initialized = 1;
920 
921 	if (Debug) {
922 		for (f = Files; f; f = f->f_next) {
923 			for (i = 0; i <= LOG_NFACILITIES; i++)
924 				if (f->f_pmask[i] == INTERNAL_NOPRI)
925 					printf("X ");
926 				else
927 					printf("%d ", f->f_pmask[i]);
928 			printf("%s: ", TypeNames[f->f_type]);
929 			switch (f->f_type) {
930 			case F_FILE:
931 			case F_TTY:
932 			case F_CONSOLE:
933 				printf("%s", f->f_un.f_fname);
934 				break;
935 
936 			case F_FORW:
937 				printf("%s", f->f_un.f_forw.f_hname);
938 				break;
939 
940 			case F_USERS:
941 				for (i = 0; i < MAXUNAMES && *f->f_un.f_uname[i]; i++)
942 					printf("%s, ", f->f_un.f_uname[i]);
943 				break;
944 			}
945 			printf("\n");
946 		}
947 	}
948 
949 	logmsg(LOG_SYSLOG|LOG_INFO, "syslogd: restart", LocalHostName, ADDDATE);
950 	dprintf("syslogd: restarted\n");
951 }
952 
953 /*
954  * Crack a configuration file line
955  */
956 
957 cfline(line, f)
958 	char *line;
959 	register struct filed *f;
960 {
961 	register char *p;
962 	register char *q;
963 	register int i;
964 	char *bp;
965 	int pri;
966 	struct hostent *hp;
967 	char buf[MAXLINE], ebuf[100];
968 
969 	dprintf("cfline(%s)\n", line);
970 
971 	errno = 0;	/* keep strerror() stuff out of logerror messages */
972 
973 	/* clear out file entry */
974 	bzero((char *) f, sizeof *f);
975 	for (i = 0; i <= LOG_NFACILITIES; i++)
976 		f->f_pmask[i] = INTERNAL_NOPRI;
977 
978 	/* scan through the list of selectors */
979 	for (p = line; *p && *p != '\t';) {
980 
981 		/* find the end of this facility name list */
982 		for (q = p; *q && *q != '\t' && *q++ != '.'; )
983 			continue;
984 
985 		/* collect priority name */
986 		for (bp = buf; *q && !index("\t,;", *q); )
987 			*bp++ = *q++;
988 		*bp = '\0';
989 
990 		/* skip cruft */
991 		while (index(", ;", *q))
992 			q++;
993 
994 		/* decode priority name */
995 		if (*buf == '*')
996 			pri = LOG_PRIMASK + 1;
997 		else {
998 			pri = decode(buf, prioritynames);
999 			if (pri < 0) {
1000 				(void) sprintf(ebuf,
1001 				    "unknown priority name \"%s\"", buf);
1002 				logerror(ebuf);
1003 				return;
1004 			}
1005 		}
1006 
1007 		/* scan facilities */
1008 		while (*p && !index("\t.;", *p)) {
1009 			for (bp = buf; *p && !index("\t,;.", *p); )
1010 				*bp++ = *p++;
1011 			*bp = '\0';
1012 			if (*buf == '*')
1013 				for (i = 0; i < LOG_NFACILITIES; i++)
1014 					f->f_pmask[i] = pri;
1015 			else {
1016 				i = decode(buf, facilitynames);
1017 				if (i < 0) {
1018 					(void) sprintf(ebuf,
1019 					    "unknown facility name \"%s\"",
1020 					    buf);
1021 					logerror(ebuf);
1022 					return;
1023 				}
1024 				f->f_pmask[i >> 3] = pri;
1025 			}
1026 			while (*p == ',' || *p == ' ')
1027 				p++;
1028 		}
1029 
1030 		p = q;
1031 	}
1032 
1033 	/* skip to action part */
1034 	while (*p == '\t')
1035 		p++;
1036 
1037 	switch (*p)
1038 	{
1039 	case '@':
1040 		if (!InetInuse)
1041 			break;
1042 		(void) strcpy(f->f_un.f_forw.f_hname, ++p);
1043 		hp = gethostbyname(p);
1044 		if (hp == NULL) {
1045 			extern int h_errno, h_nerr;
1046 			extern char **h_errlist;
1047 
1048 			logerror((u_int)h_errno < h_nerr ?
1049 			    h_errlist[h_errno] : "Unknown error");
1050 			break;
1051 		}
1052 		bzero((char *) &f->f_un.f_forw.f_addr,
1053 			 sizeof f->f_un.f_forw.f_addr);
1054 		f->f_un.f_forw.f_addr.sin_family = AF_INET;
1055 		f->f_un.f_forw.f_addr.sin_port = LogPort;
1056 		bcopy(hp->h_addr, (char *) &f->f_un.f_forw.f_addr.sin_addr, hp->h_length);
1057 		f->f_type = F_FORW;
1058 		break;
1059 
1060 	case '/':
1061 		(void) strcpy(f->f_un.f_fname, p);
1062 		if ((f->f_file = open(p, O_WRONLY|O_APPEND, 0)) < 0) {
1063 			f->f_file = F_UNUSED;
1064 			logerror(p);
1065 			break;
1066 		}
1067 		if (isatty(f->f_file))
1068 			f->f_type = F_TTY;
1069 		else
1070 			f->f_type = F_FILE;
1071 		if (strcmp(p, ctty) == 0)
1072 			f->f_type = F_CONSOLE;
1073 		break;
1074 
1075 	case '*':
1076 		f->f_type = F_WALL;
1077 		break;
1078 
1079 	default:
1080 		for (i = 0; i < MAXUNAMES && *p; i++) {
1081 			for (q = p; *q && *q != ','; )
1082 				q++;
1083 			(void) strncpy(f->f_un.f_uname[i], p, UT_NAMESIZE);
1084 			if ((q - p) > UT_NAMESIZE)
1085 				f->f_un.f_uname[i][UT_NAMESIZE] = '\0';
1086 			else
1087 				f->f_un.f_uname[i][q - p] = '\0';
1088 			while (*q == ',' || *q == ' ')
1089 				q++;
1090 			p = q;
1091 		}
1092 		f->f_type = F_USERS;
1093 		break;
1094 	}
1095 }
1096 
1097 
1098 /*
1099  *  Decode a symbolic name to a numeric value
1100  */
1101 
1102 decode(name, codetab)
1103 	char *name;
1104 	CODE *codetab;
1105 {
1106 	register CODE *c;
1107 	register char *p;
1108 	char buf[40];
1109 
1110 	if (isdigit(*name))
1111 		return (atoi(name));
1112 
1113 	(void) strcpy(buf, name);
1114 	for (p = buf; *p; p++)
1115 		if (isupper(*p))
1116 			*p = tolower(*p);
1117 	for (c = codetab; c->c_name; c++)
1118 		if (!strcmp(buf, c->c_name))
1119 			return (c->c_val);
1120 
1121 	return (-1);
1122 }
1123