xref: /netbsd-src/usr.sbin/syslogd/syslogd.c (revision ce0bb6e8d2e560ecacbe865a848624f94498063b)
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: @(#)syslogd.c	5.45 (Berkeley) 3/2/91";*/
42 static char rcsid[] = "$Id: syslogd.c,v 1.2 1993/08/01 17:55:38 mycroft Exp $";
43 #endif /* not lint */
44 
45 /*
46  *  syslogd -- log system messages
47  *
48  * This program implements a system log. It takes a series of lines.
49  * Each line may have a priority, signified as "<n>" as
50  * the first characters of the line.  If this is
51  * not present, a default priority is used.
52  *
53  * To kill syslogd, send a signal 15 (terminate).  A signal 1 (hup) will
54  * cause it to reread its configuration file.
55  *
56  * Defined Constants:
57  *
58  * MAXLINE -- the maximimum line length that can be handled.
59  * DEFUPRI -- the default priority for user messages
60  * DEFSPRI -- the default priority for kernel messages
61  *
62  * Author: Eric Allman
63  * extensive changes by Ralph Campbell
64  * more extensive changes by Eric Allman (again)
65  */
66 
67 #define	MAXLINE		1024		/* maximum line length */
68 #define	MAXSVLINE	120		/* maximum saved line length */
69 #define DEFUPRI		(LOG_USER|LOG_NOTICE)
70 #define DEFSPRI		(LOG_KERN|LOG_CRIT)
71 #define TIMERINTVL	30		/* interval for checking flush, mark */
72 
73 #include <sys/param.h>
74 #include <sys/errno.h>
75 #include <sys/ioctl.h>
76 #include <sys/stat.h>
77 #include <sys/wait.h>
78 #include <sys/socket.h>
79 #include <sys/file.h>
80 #include <sys/msgbuf.h>
81 #include <sys/uio.h>
82 #include <sys/un.h>
83 #include <sys/time.h>
84 #include <sys/resource.h>
85 #include <sys/signal.h>
86 
87 #include <netinet/in.h>
88 #include <netdb.h>
89 
90 #include <utmp.h>
91 #include <setjmp.h>
92 #include <stdio.h>
93 #include <ctype.h>
94 #include <string.h>
95 #include <unistd.h>
96 #include "pathnames.h"
97 
98 #define SYSLOG_NAMES
99 #include <sys/syslog.h>
100 
101 char	*LogName = _PATH_LOG;
102 char	*ConfFile = _PATH_LOGCONF;
103 char	*PidFile = _PATH_LOGPID;
104 char	ctty[] = _PATH_CONSOLE;
105 
106 #define FDMASK(fd)	(1 << (fd))
107 
108 #define	dprintf		if (Debug) printf
109 
110 #define MAXUNAMES	20	/* maximum number of user names */
111 
112 /*
113  * Flags to logmsg().
114  */
115 
116 #define IGN_CONS	0x001	/* don't print on console */
117 #define SYNC_FILE	0x002	/* do fsync on file after printing */
118 #define ADDDATE		0x004	/* add a date to the message */
119 #define MARK		0x008	/* this message is a mark */
120 
121 /*
122  * This structure represents the files that will have log
123  * copies printed.
124  */
125 
126 struct filed {
127 	struct	filed *f_next;		/* next in linked list */
128 	short	f_type;			/* entry type, see below */
129 	short	f_file;			/* file descriptor */
130 	time_t	f_time;			/* time this was last written */
131 	u_char	f_pmask[LOG_NFACILITIES+1];	/* priority mask */
132 	union {
133 		char	f_uname[MAXUNAMES][UT_NAMESIZE+1];
134 		struct {
135 			char	f_hname[MAXHOSTNAMELEN+1];
136 			struct sockaddr_in	f_addr;
137 		} f_forw;		/* forwarding address */
138 		char	f_fname[MAXPATHLEN];
139 	} f_un;
140 	char	f_prevline[MAXSVLINE];		/* last message logged */
141 	char	f_lasttime[16];			/* time of last occurrence */
142 	char	f_prevhost[MAXHOSTNAMELEN+1];	/* host from which recd. */
143 	int	f_prevpri;			/* pri of f_prevline */
144 	int	f_prevlen;			/* length of f_prevline */
145 	int	f_prevcount;			/* repetition cnt of prevline */
146 	int	f_repeatcount;			/* number of "repeated" msgs */
147 };
148 
149 /*
150  * Intervals at which we flush out "message repeated" messages,
151  * in seconds after previous message is logged.  After each flush,
152  * we move to the next interval until we reach the largest.
153  */
154 int	repeatinterval[] = { 30, 120, 600 };	/* # of secs before flush */
155 #define	MAXREPEAT ((sizeof(repeatinterval) / sizeof(repeatinterval[0])) - 1)
156 #define	REPEATTIME(f)	((f)->f_time + repeatinterval[(f)->f_repeatcount])
157 #define	BACKOFF(f)	{ if (++(f)->f_repeatcount > MAXREPEAT) \
158 				 (f)->f_repeatcount = MAXREPEAT; \
159 			}
160 
161 /* values for f_type */
162 #define F_UNUSED	0		/* unused entry */
163 #define F_FILE		1		/* regular file */
164 #define F_TTY		2		/* terminal */
165 #define F_CONSOLE	3		/* console terminal */
166 #define F_FORW		4		/* remote machine */
167 #define F_USERS		5		/* list of users */
168 #define F_WALL		6		/* everyone logged on */
169 
170 char	*TypeNames[7] = {
171 	"UNUSED",	"FILE",		"TTY",		"CONSOLE",
172 	"FORW",		"USERS",	"WALL"
173 };
174 
175 struct	filed *Files;
176 struct	filed consfile;
177 
178 int	Debug;			/* debug flag */
179 char	LocalHostName[MAXHOSTNAMELEN+1];	/* our hostname */
180 char	*LocalDomain;		/* our local domain name */
181 int	InetInuse = 0;		/* non-zero if INET sockets are being used */
182 int	finet;			/* Internet datagram socket */
183 int	LogPort;		/* port number for INET connections */
184 int	Initialized = 0;	/* set when we have initialized ourselves */
185 int	MarkInterval = 20 * 60;	/* interval between marks in seconds */
186 int	MarkSeq = 0;		/* mark sequence number */
187 
188 extern	int errno;
189 extern	char *ctime(), *index(), *calloc();
190 
191 main(argc, argv)
192 	int argc;
193 	char **argv;
194 {
195 	register int i;
196 	register char *p;
197 	int funix, inetm, fklog, klogm, len;
198 	struct sockaddr_un sunx, fromunix;
199 	struct sockaddr_in sin, frominet;
200 	FILE *fp;
201 	int ch;
202 	char line[MSG_BSIZE + 1];
203 	extern int optind;
204 	extern char *optarg;
205 	void die(), domark(), init(), reapchild();
206 
207 	while ((ch = getopt(argc, argv, "df:m:p:")) != EOF)
208 		switch((char)ch) {
209 		case 'd':		/* debug */
210 			Debug++;
211 			break;
212 		case 'f':		/* configuration file */
213 			ConfFile = optarg;
214 			break;
215 		case 'm':		/* mark interval */
216 			MarkInterval = atoi(optarg) * 60;
217 			break;
218 		case 'p':		/* path */
219 			LogName = optarg;
220 			break;
221 		case '?':
222 		default:
223 			usage();
224 		}
225 	if (argc -= optind)
226 		usage();
227 
228 	if (!Debug)
229 		daemon(0, 0);
230 	else
231 		setlinebuf(stdout);
232 
233 	consfile.f_type = F_CONSOLE;
234 	(void) strcpy(consfile.f_un.f_fname, ctty);
235 	(void) gethostname(LocalHostName, sizeof LocalHostName);
236 	if (p = index(LocalHostName, '.')) {
237 		*p++ = '\0';
238 		LocalDomain = p;
239 	}
240 	else
241 		LocalDomain = "";
242 	(void) signal(SIGTERM, die);
243 	(void) signal(SIGINT, Debug ? die : SIG_IGN);
244 	(void) signal(SIGQUIT, Debug ? die : SIG_IGN);
245 	(void) signal(SIGCHLD, reapchild);
246 	(void) signal(SIGALRM, domark);
247 	(void) alarm(TIMERINTVL);
248 	(void) unlink(LogName);
249 
250 	bzero((char *)&sunx, sizeof(sunx));
251 	sunx.sun_family = AF_UNIX;
252 	(void) strncpy(sunx.sun_path, LogName, sizeof sunx.sun_path);
253 	funix = socket(AF_UNIX, SOCK_DGRAM, 0);
254 	if (funix < 0 || bind(funix, (struct sockaddr *) &sunx,
255 	    sizeof(sunx.sun_family)+sizeof(sunx.sun_len)+
256 	    strlen(sunx.sun_path)) < 0 ||
257 	    chmod(LogName, 0666) < 0) {
258 		(void) sprintf(line, "cannot create %s", LogName);
259 		logerror(line);
260 		dprintf("cannot create %s (%d)\n", LogName, errno);
261 		die(0);
262 	}
263 	finet = socket(AF_INET, SOCK_DGRAM, 0);
264 	if (finet >= 0) {
265 		struct servent *sp;
266 
267 		sp = getservbyname("syslog", "udp");
268 		if (sp == NULL) {
269 			errno = 0;
270 			logerror("syslog/udp: unknown service");
271 			die(0);
272 		}
273 		bzero((char *)&sin, sizeof(sin));
274 		sin.sin_family = AF_INET;
275 		sin.sin_port = LogPort = sp->s_port;
276 		if (bind(finet, (struct sockaddr *)&sin, sizeof(sin)) < 0) {
277 			logerror("bind");
278 			if (!Debug)
279 				die(0);
280 		} else {
281 			inetm = FDMASK(finet);
282 			InetInuse = 1;
283 		}
284 	}
285 	if ((fklog = open(_PATH_KLOG, O_RDONLY, 0)) >= 0)
286 		klogm = FDMASK(fklog);
287 	else {
288 		dprintf("can't open %s (%d)\n", _PATH_KLOG, errno);
289 		klogm = 0;
290 	}
291 
292 	/* tuck my process id away */
293 	fp = fopen(PidFile, "w");
294 	if (fp != NULL) {
295 		fprintf(fp, "%d\n", getpid());
296 		(void) fclose(fp);
297 	}
298 
299 	dprintf("off & running....\n");
300 
301 	init();
302 	(void) signal(SIGHUP, init);
303 
304 	for (;;) {
305 		int nfds, readfds = FDMASK(funix) | inetm | klogm;
306 
307 		errno = 0;
308 		dprintf("readfds = %#x\n", readfds);
309 		nfds = select(20, (fd_set *) &readfds, (fd_set *) NULL,
310 		    (fd_set *) NULL, (struct timeval *) NULL);
311 		if (nfds == 0)
312 			continue;
313 		if (nfds < 0) {
314 			if (errno != EINTR)
315 				logerror("select");
316 			continue;
317 		}
318 		dprintf("got a message (%d, %#x)\n", nfds, readfds);
319 		if (readfds & klogm) {
320 			i = read(fklog, line, sizeof(line) - 1);
321 			if (i > 0) {
322 				line[i] = '\0';
323 				printsys(line);
324 			} else if (i < 0 && errno != EINTR) {
325 				logerror("klog");
326 				fklog = -1;
327 				klogm = 0;
328 			}
329 		}
330 		if (readfds & FDMASK(funix)) {
331 			len = sizeof fromunix;
332 			i = recvfrom(funix, line, MAXLINE, 0,
333 			    (struct sockaddr *) &fromunix, &len);
334 			if (i > 0) {
335 				line[i] = '\0';
336 				printline(LocalHostName, line);
337 			} else if (i < 0 && errno != EINTR)
338 				logerror("recvfrom unix");
339 		}
340 		if (readfds & inetm) {
341 			len = sizeof frominet;
342 			i = recvfrom(finet, line, MAXLINE, 0,
343 			    (struct sockaddr *) &frominet, &len);
344 			if (i > 0) {
345 				extern char *cvthname();
346 
347 				line[i] = '\0';
348 				printline(cvthname(&frominet), line);
349 			} else if (i < 0 && errno != EINTR)
350 				logerror("recvfrom inet");
351 		}
352 	}
353 }
354 
355 usage()
356 {
357 	(void) fprintf(stderr,
358 	    "usage: syslogd [-f conffile] [-m markinterval] [-p logpath]\n");
359 	exit(1);
360 }
361 
362 /*
363  * Take a raw input line, decode the message, and print the message
364  * on the appropriate log files.
365  */
366 
367 printline(hname, msg)
368 	char *hname;
369 	char *msg;
370 {
371 	register char *p, *q;
372 	register int c;
373 	char line[MAXLINE + 1];
374 	int pri;
375 
376 	/* test for special codes */
377 	pri = DEFUPRI;
378 	p = msg;
379 	if (*p == '<') {
380 		pri = 0;
381 		while (isdigit(*++p))
382 			pri = 10 * pri + (*p - '0');
383 		if (*p == '>')
384 			++p;
385 	}
386 	if (pri &~ (LOG_FACMASK|LOG_PRIMASK))
387 		pri = DEFUPRI;
388 
389 	/* don't allow users to log kernel messages */
390 	if (LOG_FAC(pri) == LOG_KERN)
391 		pri = LOG_MAKEPRI(LOG_USER, LOG_PRI(pri));
392 
393 	q = line;
394 
395 	while ((c = *p++ & 0177) != '\0' &&
396 	    q < &line[sizeof(line) - 1])
397 		if (iscntrl(c))
398 			if (c == '\n')
399 				*q++ = ' ';
400 			else if (c == '\t')
401 				*q++ = '\t';
402 			else {
403 				*q++ = '^';
404 				*q++ = c ^ 0100;
405 			}
406 		else
407 			*q++ = c;
408 	*q = '\0';
409 
410 	logmsg(pri, line, hname, 0);
411 }
412 
413 /*
414  * Take a raw input line from /dev/klog, split and format similar to syslog().
415  */
416 
417 printsys(msg)
418 	char *msg;
419 {
420 	register char *p, *q;
421 	register int c;
422 	char line[MAXLINE + 1];
423 	int pri, flags;
424 	char *lp;
425 
426 	(void) strcpy(line, _PATH_UNIX);
427 	(void) strcat(line, ": ");
428 	lp = line + strlen(line);
429 	for (p = msg; *p != '\0'; ) {
430 		flags = SYNC_FILE | ADDDATE;	/* fsync file after write */
431 		pri = DEFSPRI;
432 		if (*p == '<') {
433 			pri = 0;
434 			while (isdigit(*++p))
435 				pri = 10 * pri + (*p - '0');
436 			if (*p == '>')
437 				++p;
438 		} else {
439 			/* kernel printf's come out on console */
440 			flags |= IGN_CONS;
441 		}
442 		if (pri &~ (LOG_FACMASK|LOG_PRIMASK))
443 			pri = DEFSPRI;
444 		q = lp;
445 		while (*p != '\0' && (c = *p++) != '\n' &&
446 		    q < &line[MAXLINE])
447 			*q++ = c;
448 		*q = '\0';
449 		logmsg(pri, line, LocalHostName, flags);
450 	}
451 }
452 
453 time_t	now;
454 
455 /*
456  * Log a message to the appropriate log files, users, etc. based on
457  * the priority.
458  */
459 
460 logmsg(pri, msg, from, flags)
461 	int pri;
462 	char *msg, *from;
463 	int flags;
464 {
465 	register struct filed *f;
466 	int fac, prilev;
467 	int omask, msglen;
468 	char *timestamp;
469 	time_t time();
470 
471 	dprintf("logmsg: pri %o, flags %x, from %s, msg %s\n",
472 	    pri, flags, from, msg);
473 
474 	omask = sigblock(sigmask(SIGHUP)|sigmask(SIGALRM));
475 
476 	/*
477 	 * Check to see if msg looks non-standard.
478 	 */
479 	msglen = strlen(msg);
480 	if (msglen < 16 || msg[3] != ' ' || msg[6] != ' ' ||
481 	    msg[9] != ':' || msg[12] != ':' || msg[15] != ' ')
482 		flags |= ADDDATE;
483 
484 	(void) time(&now);
485 	if (flags & ADDDATE)
486 		timestamp = ctime(&now) + 4;
487 	else {
488 		timestamp = msg;
489 		msg += 16;
490 		msglen -= 16;
491 	}
492 
493 	/* extract facility and priority level */
494 	if (flags & MARK)
495 		fac = LOG_NFACILITIES;
496 	else
497 		fac = LOG_FAC(pri);
498 	prilev = LOG_PRI(pri);
499 
500 	/* log the message to the particular outputs */
501 	if (!Initialized) {
502 		f = &consfile;
503 		f->f_file = open(ctty, O_WRONLY, 0);
504 
505 		if (f->f_file >= 0) {
506 			fprintlog(f, flags, msg);
507 			(void) close(f->f_file);
508 		}
509 		(void) sigsetmask(omask);
510 		return;
511 	}
512 	for (f = Files; f; f = f->f_next) {
513 		/* skip messages that are incorrect priority */
514 		if (f->f_pmask[fac] < prilev ||
515 		    f->f_pmask[fac] == INTERNAL_NOPRI)
516 			continue;
517 
518 		if (f->f_type == F_CONSOLE && (flags & IGN_CONS))
519 			continue;
520 
521 		/* don't output marks to recently written files */
522 		if ((flags & MARK) && (now - f->f_time) < MarkInterval / 2)
523 			continue;
524 
525 		/*
526 		 * suppress duplicate lines to this file
527 		 */
528 		if ((flags & MARK) == 0 && msglen == f->f_prevlen &&
529 		    !strcmp(msg, f->f_prevline) &&
530 		    !strcmp(from, f->f_prevhost)) {
531 			(void) strncpy(f->f_lasttime, timestamp, 15);
532 			f->f_prevcount++;
533 			dprintf("msg repeated %d times, %ld sec of %d\n",
534 			    f->f_prevcount, now - f->f_time,
535 			    repeatinterval[f->f_repeatcount]);
536 			/*
537 			 * If domark would have logged this by now,
538 			 * flush it now (so we don't hold isolated messages),
539 			 * but back off so we'll flush less often
540 			 * in the future.
541 			 */
542 			if (now > REPEATTIME(f)) {
543 				fprintlog(f, flags, (char *)NULL);
544 				BACKOFF(f);
545 			}
546 		} else {
547 			/* new line, save it */
548 			if (f->f_prevcount)
549 				fprintlog(f, 0, (char *)NULL);
550 			f->f_repeatcount = 0;
551 			(void) strncpy(f->f_lasttime, timestamp, 15);
552 			(void) strncpy(f->f_prevhost, from,
553 					sizeof(f->f_prevhost));
554 			if (msglen < MAXSVLINE) {
555 				f->f_prevlen = msglen;
556 				f->f_prevpri = pri;
557 				(void) strcpy(f->f_prevline, msg);
558 				fprintlog(f, flags, (char *)NULL);
559 			} else {
560 				f->f_prevline[0] = 0;
561 				f->f_prevlen = 0;
562 				fprintlog(f, flags, msg);
563 			}
564 		}
565 	}
566 	(void) sigsetmask(omask);
567 }
568 
569 fprintlog(f, flags, msg)
570 	register struct filed *f;
571 	int flags;
572 	char *msg;
573 {
574 	struct iovec iov[6];
575 	register struct iovec *v;
576 	register int l;
577 	char line[MAXLINE + 1], repbuf[80], greetings[200];
578 
579 	v = iov;
580 	if (f->f_type == F_WALL) {
581 		v->iov_base = greetings;
582 		v->iov_len = sprintf(greetings,
583 		    "\r\n\7Message from syslogd@%s at %.24s ...\r\n",
584 		    f->f_prevhost, ctime(&now));
585 		v++;
586 		v->iov_base = "";
587 		v->iov_len = 0;
588 		v++;
589 	} else {
590 		v->iov_base = f->f_lasttime;
591 		v->iov_len = 15;
592 		v++;
593 		v->iov_base = " ";
594 		v->iov_len = 1;
595 		v++;
596 	}
597 	v->iov_base = f->f_prevhost;
598 	v->iov_len = strlen(v->iov_base);
599 	v++;
600 	v->iov_base = " ";
601 	v->iov_len = 1;
602 	v++;
603 
604 	if (msg) {
605 		v->iov_base = msg;
606 		v->iov_len = strlen(msg);
607 	} else if (f->f_prevcount > 1) {
608 		v->iov_base = repbuf;
609 		v->iov_len = sprintf(repbuf, "last message repeated %d times",
610 		    f->f_prevcount);
611 	} else {
612 		v->iov_base = f->f_prevline;
613 		v->iov_len = f->f_prevlen;
614 	}
615 	v++;
616 
617 	dprintf("Logging to %s", TypeNames[f->f_type]);
618 	f->f_time = now;
619 
620 	switch (f->f_type) {
621 	case F_UNUSED:
622 		dprintf("\n");
623 		break;
624 
625 	case F_FORW:
626 		dprintf(" %s\n", f->f_un.f_forw.f_hname);
627 		l = sprintf(line, "<%d>%.15s %s", f->f_prevpri,
628 		    iov[0].iov_base, iov[4].iov_base);
629 		if (l > MAXLINE)
630 			l = MAXLINE;
631 		if (sendto(finet, line, l, 0,
632 		    (struct sockaddr *)&f->f_un.f_forw.f_addr,
633 		    sizeof f->f_un.f_forw.f_addr) != l) {
634 			int e = errno;
635 			(void) close(f->f_file);
636 			f->f_type = F_UNUSED;
637 			errno = e;
638 			logerror("sendto");
639 		}
640 		break;
641 
642 	case F_CONSOLE:
643 		if (flags & IGN_CONS) {
644 			dprintf(" (ignored)\n");
645 			break;
646 		}
647 		/* FALLTHROUGH */
648 
649 	case F_TTY:
650 	case F_FILE:
651 		dprintf(" %s\n", f->f_un.f_fname);
652 		if (f->f_type != F_FILE) {
653 			v->iov_base = "\r\n";
654 			v->iov_len = 2;
655 		} else {
656 			v->iov_base = "\n";
657 			v->iov_len = 1;
658 		}
659 	again:
660 		if (writev(f->f_file, iov, 6) < 0) {
661 			int e = errno;
662 			(void) close(f->f_file);
663 			/*
664 			 * Check for errors on TTY's due to loss of tty
665 			 */
666 			if ((e == EIO || e == EBADF) && f->f_type != F_FILE) {
667 				f->f_file = open(f->f_un.f_fname,
668 				    O_WRONLY|O_APPEND, 0);
669 				if (f->f_file < 0) {
670 					f->f_type = F_UNUSED;
671 					logerror(f->f_un.f_fname);
672 				} else
673 					goto again;
674 			} else {
675 				f->f_type = F_UNUSED;
676 				errno = e;
677 				logerror(f->f_un.f_fname);
678 			}
679 		} else if (flags & SYNC_FILE)
680 			(void) fsync(f->f_file);
681 		break;
682 
683 	case F_USERS:
684 	case F_WALL:
685 		dprintf("\n");
686 		v->iov_base = "\r\n";
687 		v->iov_len = 2;
688 		wallmsg(f, iov);
689 		break;
690 	}
691 	f->f_prevcount = 0;
692 }
693 
694 /*
695  *  WALLMSG -- Write a message to the world at large
696  *
697  *	Write the specified message to either the entire
698  *	world, or a list of approved users.
699  */
700 
701 wallmsg(f, iov)
702 	register struct filed *f;
703 	struct iovec *iov;
704 {
705 	static int reenter;			/* avoid calling ourselves */
706 	register FILE *uf;
707 	register int i;
708 	struct utmp ut;
709 	char *p, *ttymsg();
710 
711 	if (reenter++)
712 		return;
713 	if ((uf = fopen(_PATH_UTMP, "r")) == NULL) {
714 		logerror(_PATH_UTMP);
715 		reenter = 0;
716 		return;
717 	}
718 	/* NOSTRICT */
719 	while (fread((char *) &ut, sizeof ut, 1, uf) == 1) {
720 		if (ut.ut_name[0] == '\0')
721 			continue;
722 		if (f->f_type == F_WALL) {
723 			if (p = ttymsg(iov, 6, ut.ut_line, 1)) {
724 				errno = 0;	/* already in msg */
725 				logerror(p);
726 			}
727 			continue;
728 		}
729 		/* should we send the message to this user? */
730 		for (i = 0; i < MAXUNAMES; i++) {
731 			if (!f->f_un.f_uname[i][0])
732 				break;
733 			if (!strncmp(f->f_un.f_uname[i], ut.ut_name,
734 			    UT_NAMESIZE)) {
735 				if (p = ttymsg(iov, 6, ut.ut_line, 1)) {
736 					errno = 0;	/* already in msg */
737 					logerror(p);
738 				}
739 				break;
740 			}
741 		}
742 	}
743 	(void) fclose(uf);
744 	reenter = 0;
745 }
746 
747 void
748 reapchild()
749 {
750 	union wait status;
751 
752 	while (wait3((int *)&status, WNOHANG, (struct rusage *) NULL) > 0)
753 		;
754 }
755 
756 /*
757  * Return a printable representation of a host address.
758  */
759 char *
760 cvthname(f)
761 	struct sockaddr_in *f;
762 {
763 	struct hostent *hp;
764 	register char *p;
765 	extern char *inet_ntoa();
766 
767 	dprintf("cvthname(%s)\n", inet_ntoa(f->sin_addr));
768 
769 	if (f->sin_family != AF_INET) {
770 		dprintf("Malformed from address\n");
771 		return ("???");
772 	}
773 	hp = gethostbyaddr((char *)&f->sin_addr,
774 	    sizeof(struct in_addr), f->sin_family);
775 	if (hp == 0) {
776 		dprintf("Host name for your address (%s) unknown\n",
777 			inet_ntoa(f->sin_addr));
778 		return (inet_ntoa(f->sin_addr));
779 	}
780 	if ((p = index(hp->h_name, '.')) && strcmp(p + 1, LocalDomain) == 0)
781 		*p = '\0';
782 	return (hp->h_name);
783 }
784 
785 void
786 domark()
787 {
788 	register struct filed *f;
789 	time_t time();
790 
791 	now = time((time_t *)NULL);
792 	MarkSeq += TIMERINTVL;
793 	if (MarkSeq >= MarkInterval) {
794 		logmsg(LOG_INFO, "-- MARK --", LocalHostName, ADDDATE|MARK);
795 		MarkSeq = 0;
796 	}
797 
798 	for (f = Files; f; f = f->f_next) {
799 		if (f->f_prevcount && now >= REPEATTIME(f)) {
800 			dprintf("flush %s: repeated %d times, %d sec.\n",
801 			    TypeNames[f->f_type], f->f_prevcount,
802 			    repeatinterval[f->f_repeatcount]);
803 			fprintlog(f, 0, (char *)NULL);
804 			BACKOFF(f);
805 		}
806 	}
807 	(void) alarm(TIMERINTVL);
808 }
809 
810 /*
811  * Print syslogd errors some place.
812  */
813 logerror(type)
814 	char *type;
815 {
816 	char buf[100], *strerror();
817 
818 	if (errno)
819 		(void) sprintf(buf, "syslogd: %s: %s", type, strerror(errno));
820 	else
821 		(void) sprintf(buf, "syslogd: %s", type);
822 	errno = 0;
823 	dprintf("%s\n", buf);
824 	logmsg(LOG_SYSLOG|LOG_ERR, buf, LocalHostName, ADDDATE);
825 }
826 
827 void
828 die(sig)
829 {
830 	register struct filed *f;
831 	char buf[100];
832 
833 	for (f = Files; f != NULL; f = f->f_next) {
834 		/* flush any pending output */
835 		if (f->f_prevcount)
836 			fprintlog(f, 0, (char *)NULL);
837 	}
838 	if (sig) {
839 		dprintf("syslogd: exiting on signal %d\n", sig);
840 		(void) sprintf(buf, "exiting on signal %d", sig);
841 		errno = 0;
842 		logerror(buf);
843 	}
844 	(void) unlink(LogName);
845 	exit(0);
846 }
847 
848 /*
849  *  INIT -- Initialize syslogd from configuration table
850  */
851 
852 void
853 init()
854 {
855 	register int i;
856 	register FILE *cf;
857 	register struct filed *f, *next, **nextp;
858 	register char *p;
859 	char cline[BUFSIZ];
860 
861 	dprintf("init\n");
862 
863 	/*
864 	 *  Close all open log files.
865 	 */
866 	Initialized = 0;
867 	for (f = Files; f != NULL; f = next) {
868 		/* flush any pending output */
869 		if (f->f_prevcount)
870 			fprintlog(f, 0, (char *)NULL);
871 
872 		switch (f->f_type) {
873 		  case F_FILE:
874 		  case F_TTY:
875 		  case F_CONSOLE:
876 		  case F_FORW:
877 			(void) close(f->f_file);
878 			break;
879 		}
880 		next = f->f_next;
881 		free((char *) f);
882 	}
883 	Files = NULL;
884 	nextp = &Files;
885 
886 	/* open the configuration file */
887 	if ((cf = fopen(ConfFile, "r")) == NULL) {
888 		dprintf("cannot open %s\n", ConfFile);
889 		*nextp = (struct filed *)calloc(1, sizeof(*f));
890 		cfline("*.ERR\t/dev/console", *nextp);
891 		(*nextp)->f_next = (struct filed *)calloc(1, sizeof(*f));
892 		cfline("*.PANIC\t*", (*nextp)->f_next);
893 		Initialized = 1;
894 		return;
895 	}
896 
897 	/*
898 	 *  Foreach line in the conf table, open that file.
899 	 */
900 	f = NULL;
901 	while (fgets(cline, sizeof cline, cf) != NULL) {
902 		/*
903 		 * check for end-of-section, comments, strip off trailing
904 		 * spaces and newline character.
905 		 */
906 		for (p = cline; isspace(*p); ++p);
907 		if (*p == NULL || *p == '#')
908 			continue;
909 		for (p = index(cline, '\0'); isspace(*--p););
910 		*++p = '\0';
911 		f = (struct filed *)calloc(1, sizeof(*f));
912 		*nextp = f;
913 		nextp = &f->f_next;
914 		cfline(cline, f);
915 	}
916 
917 	/* close the configuration file */
918 	(void) fclose(cf);
919 
920 	Initialized = 1;
921 
922 	if (Debug) {
923 		for (f = Files; f; f = f->f_next) {
924 			for (i = 0; i <= LOG_NFACILITIES; i++)
925 				if (f->f_pmask[i] == INTERNAL_NOPRI)
926 					printf("X ");
927 				else
928 					printf("%d ", f->f_pmask[i]);
929 			printf("%s: ", TypeNames[f->f_type]);
930 			switch (f->f_type) {
931 			case F_FILE:
932 			case F_TTY:
933 			case F_CONSOLE:
934 				printf("%s", f->f_un.f_fname);
935 				break;
936 
937 			case F_FORW:
938 				printf("%s", f->f_un.f_forw.f_hname);
939 				break;
940 
941 			case F_USERS:
942 				for (i = 0; i < MAXUNAMES && *f->f_un.f_uname[i]; i++)
943 					printf("%s, ", f->f_un.f_uname[i]);
944 				break;
945 			}
946 			printf("\n");
947 		}
948 	}
949 
950 	logmsg(LOG_SYSLOG|LOG_INFO, "syslogd: restart", LocalHostName, ADDDATE);
951 	dprintf("syslogd: restarted\n");
952 }
953 
954 /*
955  * Crack a configuration file line
956  */
957 
958 cfline(line, f)
959 	char *line;
960 	register struct filed *f;
961 {
962 	register char *p;
963 	register char *q;
964 	register int i;
965 	char *bp;
966 	int pri;
967 	struct hostent *hp;
968 	char buf[MAXLINE], ebuf[100];
969 
970 	dprintf("cfline(%s)\n", line);
971 
972 	errno = 0;	/* keep strerror() stuff out of logerror messages */
973 
974 	/* clear out file entry */
975 	bzero((char *) f, sizeof *f);
976 	for (i = 0; i <= LOG_NFACILITIES; i++)
977 		f->f_pmask[i] = INTERNAL_NOPRI;
978 
979 	/* scan through the list of selectors */
980 	for (p = line; *p && *p != '\t';) {
981 
982 		/* find the end of this facility name list */
983 		for (q = p; *q && *q != '\t' && *q++ != '.'; )
984 			continue;
985 
986 		/* collect priority name */
987 		for (bp = buf; *q && !index("\t,;", *q); )
988 			*bp++ = *q++;
989 		*bp = '\0';
990 
991 		/* skip cruft */
992 		while (index(", ;", *q))
993 			q++;
994 
995 		/* decode priority name */
996 		if (*buf == '*')
997 			pri = LOG_PRIMASK + 1;
998 		else {
999 			pri = decode(buf, prioritynames);
1000 			if (pri < 0) {
1001 				(void) sprintf(ebuf,
1002 				    "unknown priority name \"%s\"", buf);
1003 				logerror(ebuf);
1004 				return;
1005 			}
1006 		}
1007 
1008 		/* scan facilities */
1009 		while (*p && !index("\t.;", *p)) {
1010 			for (bp = buf; *p && !index("\t,;.", *p); )
1011 				*bp++ = *p++;
1012 			*bp = '\0';
1013 			if (*buf == '*')
1014 				for (i = 0; i < LOG_NFACILITIES; i++)
1015 					f->f_pmask[i] = pri;
1016 			else {
1017 				i = decode(buf, facilitynames);
1018 				if (i < 0) {
1019 					(void) sprintf(ebuf,
1020 					    "unknown facility name \"%s\"",
1021 					    buf);
1022 					logerror(ebuf);
1023 					return;
1024 				}
1025 				f->f_pmask[i >> 3] = pri;
1026 			}
1027 			while (*p == ',' || *p == ' ')
1028 				p++;
1029 		}
1030 
1031 		p = q;
1032 	}
1033 
1034 	/* skip to action part */
1035 	while (*p == '\t')
1036 		p++;
1037 
1038 	switch (*p)
1039 	{
1040 	case '@':
1041 		if (!InetInuse)
1042 			break;
1043 		(void) strcpy(f->f_un.f_forw.f_hname, ++p);
1044 		hp = gethostbyname(p);
1045 		if (hp == NULL) {
1046 			extern int h_errno, h_nerr;
1047 			extern char **h_errlist;
1048 
1049 			logerror((u_int)h_errno < h_nerr ?
1050 			    h_errlist[h_errno] : "Unknown error");
1051 			break;
1052 		}
1053 		bzero((char *) &f->f_un.f_forw.f_addr,
1054 			 sizeof f->f_un.f_forw.f_addr);
1055 		f->f_un.f_forw.f_addr.sin_family = AF_INET;
1056 		f->f_un.f_forw.f_addr.sin_port = LogPort;
1057 		bcopy(hp->h_addr, (char *) &f->f_un.f_forw.f_addr.sin_addr, hp->h_length);
1058 		f->f_type = F_FORW;
1059 		break;
1060 
1061 	case '/':
1062 		(void) strcpy(f->f_un.f_fname, p);
1063 		if ((f->f_file = open(p, O_WRONLY|O_APPEND, 0)) < 0) {
1064 			f->f_file = F_UNUSED;
1065 			logerror(p);
1066 			break;
1067 		}
1068 		if (isatty(f->f_file))
1069 			f->f_type = F_TTY;
1070 		else
1071 			f->f_type = F_FILE;
1072 		if (strcmp(p, ctty) == 0)
1073 			f->f_type = F_CONSOLE;
1074 		break;
1075 
1076 	case '*':
1077 		f->f_type = F_WALL;
1078 		break;
1079 
1080 	default:
1081 		for (i = 0; i < MAXUNAMES && *p; i++) {
1082 			for (q = p; *q && *q != ','; )
1083 				q++;
1084 			(void) strncpy(f->f_un.f_uname[i], p, UT_NAMESIZE);
1085 			if ((q - p) > UT_NAMESIZE)
1086 				f->f_un.f_uname[i][UT_NAMESIZE] = '\0';
1087 			else
1088 				f->f_un.f_uname[i][q - p] = '\0';
1089 			while (*q == ',' || *q == ' ')
1090 				q++;
1091 			p = q;
1092 		}
1093 		f->f_type = F_USERS;
1094 		break;
1095 	}
1096 }
1097 
1098 
1099 /*
1100  *  Decode a symbolic name to a numeric value
1101  */
1102 
1103 decode(name, codetab)
1104 	char *name;
1105 	CODE *codetab;
1106 {
1107 	register CODE *c;
1108 	register char *p;
1109 	char buf[40];
1110 
1111 	if (isdigit(*name))
1112 		return (atoi(name));
1113 
1114 	(void) strcpy(buf, name);
1115 	for (p = buf; *p; p++)
1116 		if (isupper(*p))
1117 			*p = tolower(*p);
1118 	for (c = codetab; c->c_name; c++)
1119 		if (!strcmp(buf, c->c_name))
1120 			return (c->c_val);
1121 
1122 	return (-1);
1123 }
1124