xref: /netbsd-src/usr.sbin/syslogd/syslogd.c (revision 3b435a73967be44dfb4a27315acd72bfacde430c)
1 /*
2  * Copyright (c) 1983, 1988, 1993, 1994
3  *	The Regents of the University of California.  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 #include <sys/cdefs.h>
35 #ifndef lint
36 __COPYRIGHT("@(#) Copyright (c) 1983, 1988, 1993, 1994\n\
37 	The Regents of the University of California.  All rights reserved.\n");
38 #endif /* not lint */
39 
40 #ifndef lint
41 #if 0
42 static char sccsid[] = "@(#)syslogd.c	8.3 (Berkeley) 4/4/94";
43 #else
44 __RCSID("$NetBSD: syslogd.c,v 1.28 1999/06/07 15:34:07 lukem Exp $");
45 #endif
46 #endif /* not lint */
47 
48 /*
49  *  syslogd -- log system messages
50  *
51  * This program implements a system log. It takes a series of lines.
52  * Each line may have a priority, signified as "<n>" as
53  * the first characters of the line.  If this is
54  * not present, a default priority is used.
55  *
56  * To kill syslogd, send a signal 15 (terminate).  A signal 1 (hup) will
57  * cause it to reread its configuration file.
58  *
59  * Defined Constants:
60  *
61  * MAXLINE -- the maximimum line length that can be handled.
62  * DEFUPRI -- the default priority for user messages
63  * DEFSPRI -- the default priority for kernel messages
64  *
65  * Author: Eric Allman
66  * extensive changes by Ralph Campbell
67  * more extensive changes by Eric Allman (again)
68  */
69 
70 #define	MAXLINE		1024		/* maximum line length */
71 #define	MAXSVLINE	120		/* maximum saved line length */
72 #define DEFUPRI		(LOG_USER|LOG_NOTICE)
73 #define DEFSPRI		(LOG_KERN|LOG_CRIT)
74 #define TIMERINTVL	30		/* interval for checking flush, mark */
75 #define TTYMSGTIME	1		/* timeout passed to ttymsg */
76 
77 #include <sys/param.h>
78 #include <sys/ioctl.h>
79 #include <sys/stat.h>
80 #include <sys/wait.h>
81 #include <sys/socket.h>
82 #include <sys/msgbuf.h>
83 #include <sys/uio.h>
84 #include <sys/poll.h>
85 #include <sys/un.h>
86 #include <sys/time.h>
87 #include <sys/resource.h>
88 #include <sys/sysctl.h>
89 
90 #include <netinet/in.h>
91 #include <netdb.h>
92 #include <arpa/inet.h>
93 
94 #include <ctype.h>
95 #include <errno.h>
96 #include <fcntl.h>
97 #include <setjmp.h>
98 #include <signal.h>
99 #include <stdio.h>
100 #include <stdlib.h>
101 #include <string.h>
102 #include <unistd.h>
103 #include <utmp.h>
104 #include <util.h>
105 #include "pathnames.h"
106 
107 #define SYSLOG_NAMES
108 #include <sys/syslog.h>
109 
110 char	*ConfFile = _PATH_LOGCONF;
111 char	ctty[] = _PATH_CONSOLE;
112 
113 #define FDMASK(fd)	(1 << (fd))
114 
115 #define	dprintf		if (Debug) printf
116 
117 #define MAXUNAMES	20	/* maximum number of user names */
118 
119 /*
120  * Flags to logmsg().
121  */
122 
123 #define IGN_CONS	0x001	/* don't print on console */
124 #define SYNC_FILE	0x002	/* do fsync on file after printing */
125 #define ADDDATE		0x004	/* add a date to the message */
126 #define MARK		0x008	/* this message is a mark */
127 
128 /*
129  * This structure represents the files that will have log
130  * copies printed.
131  */
132 
133 struct filed {
134 	struct	filed *f_next;		/* next in linked list */
135 	short	f_type;			/* entry type, see below */
136 	short	f_file;			/* file descriptor */
137 	time_t	f_time;			/* time this was last written */
138 	u_char	f_pmask[LOG_NFACILITIES+1];	/* priority mask */
139 	union {
140 		char	f_uname[MAXUNAMES][UT_NAMESIZE+1];
141 		struct {
142 			char	f_hname[MAXHOSTNAMELEN+1];
143 			struct sockaddr_in	f_addr;
144 		} f_forw;		/* forwarding address */
145 		char	f_fname[MAXPATHLEN];
146 	} f_un;
147 	char	f_prevline[MAXSVLINE];		/* last message logged */
148 	char	f_lasttime[16];			/* time of last occurrence */
149 	char	f_prevhost[MAXHOSTNAMELEN+1];	/* host from which recd. */
150 	int	f_prevpri;			/* pri of f_prevline */
151 	int	f_prevlen;			/* length of f_prevline */
152 	int	f_prevcount;			/* repetition cnt of prevline */
153 	int	f_repeatcount;			/* number of "repeated" msgs */
154 };
155 
156 /*
157  * Intervals at which we flush out "message repeated" messages,
158  * in seconds after previous message is logged.  After each flush,
159  * we move to the next interval until we reach the largest.
160  */
161 int	repeatinterval[] = { 30, 120, 600 };	/* # of secs before flush */
162 #define	MAXREPEAT ((sizeof(repeatinterval) / sizeof(repeatinterval[0])) - 1)
163 #define	REPEATTIME(f)	((f)->f_time + repeatinterval[(f)->f_repeatcount])
164 #define	BACKOFF(f)	{ if (++(f)->f_repeatcount > MAXREPEAT) \
165 				 (f)->f_repeatcount = MAXREPEAT; \
166 			}
167 
168 /* values for f_type */
169 #define F_UNUSED	0		/* unused entry */
170 #define F_FILE		1		/* regular file */
171 #define F_TTY		2		/* terminal */
172 #define F_CONSOLE	3		/* console terminal */
173 #define F_FORW		4		/* remote machine */
174 #define F_USERS		5		/* list of users */
175 #define F_WALL		6		/* everyone logged on */
176 
177 char	*TypeNames[7] = {
178 	"UNUSED",	"FILE",		"TTY",		"CONSOLE",
179 	"FORW",		"USERS",	"WALL"
180 };
181 
182 struct	filed *Files;
183 struct	filed consfile;
184 
185 int	Debug;			/* debug flag */
186 char	LocalHostName[MAXHOSTNAMELEN+1];	/* our hostname */
187 char	*LocalDomain;		/* our local domain name */
188 int	InetInuse = 0;		/* non-zero if INET sockets are being used */
189 int	finet;			/* Internet datagram socket */
190 int	LogPort;		/* port number for INET connections */
191 int	Initialized = 0;	/* set when we have initialized ourselves */
192 int	MarkInterval = 20 * 60;	/* interval between marks in seconds */
193 int	MarkSeq = 0;		/* mark sequence number */
194 int	SecureMode = 0;		/* when true, speak only unix domain socks */
195 char	**LogPaths;		/* array of pathnames to read messages from */
196 
197 void	cfline __P((char *, struct filed *));
198 char   *cvthname __P((struct sockaddr_in *));
199 int	decode __P((const char *, CODE *));
200 void	die __P((int));
201 void	domark __P((int));
202 void	fprintlog __P((struct filed *, int, char *));
203 int	getmsgbufsize __P((void));
204 void	init __P((int));
205 void	logerror __P((char *));
206 void	logmsg __P((int, char *, char *, int));
207 void	printline __P((char *, char *));
208 void	printsys __P((char *));
209 void	reapchild __P((int));
210 void	usage __P((void));
211 void	wallmsg __P((struct filed *, struct iovec *));
212 int	main __P((int, char *[]));
213 void	logpath_add __P((char ***, int *, int *, char *));
214 void	logpath_fileadd __P((char ***, int *, int *, char *));
215 
216 int
217 main(argc, argv)
218 	int argc;
219 	char *argv[];
220 {
221 	int ch, *funix, i, j, fklog, len, linesize;
222 	int nfinetix, nfklogix, nfunixbaseix, nfds;
223 	int funixsize = 0, funixmaxsize = 0;
224 	struct sockaddr_un sunx, fromunix;
225 	struct sockaddr_in sin, frominet;
226 	char *p, *line, **pp;
227 	struct pollfd *readfds;
228 
229 	while ((ch = getopt(argc, argv, "dsf:m:p:P:")) != -1)
230 		switch(ch) {
231 		case 'd':		/* debug */
232 			Debug++;
233 			break;
234 		case 'f':		/* configuration file */
235 			ConfFile = optarg;
236 			break;
237 		case 'm':		/* mark interval */
238 			MarkInterval = atoi(optarg) * 60;
239 			break;
240 		case 'p':		/* path */
241 			logpath_add(&LogPaths, &funixsize,
242 			    &funixmaxsize, optarg);
243 			break;
244 		case 'P':		/* file of paths */
245 			logpath_fileadd(&LogPaths, &funixsize,
246 			    &funixmaxsize, optarg);
247 			break;
248 		case 's':		/* no network mode */
249 			SecureMode++;
250 			break;
251 		case '?':
252 		default:
253 			usage();
254 		}
255 	if ((argc -= optind) != 0)
256 		usage();
257 
258 	if (!Debug)
259 		(void)daemon(0, 0);
260 	else
261 		setlinebuf(stdout);
262 
263 	consfile.f_type = F_CONSOLE;
264 	(void)strcpy(consfile.f_un.f_fname, ctty);
265 	(void)gethostname(LocalHostName, sizeof(LocalHostName));
266 	LocalHostName[sizeof(LocalHostName) - 1] = '\0';
267 	if ((p = strchr(LocalHostName, '.')) != NULL) {
268 		*p++ = '\0';
269 		LocalDomain = p;
270 	} else
271 		LocalDomain = "";
272 	linesize = getmsgbufsize();
273 	if (linesize < MAXLINE)
274 		linesize = MAXLINE;
275 	linesize++;
276 	line = malloc(linesize);
277 	if (line == NULL) {
278 		logerror("couldn't allocate line buffer");
279 		die(0);
280 	}
281 	(void)signal(SIGTERM, die);
282 	(void)signal(SIGINT, Debug ? die : SIG_IGN);
283 	(void)signal(SIGQUIT, Debug ? die : SIG_IGN);
284 	(void)signal(SIGCHLD, reapchild);
285 	(void)signal(SIGALRM, domark);
286 	(void)alarm(TIMERINTVL);
287 
288 #ifndef SUN_LEN
289 #define SUN_LEN(unp) (strlen((unp)->sun_path) + 2)
290 #endif
291 	if (funixsize == 0)
292 		logpath_add(&LogPaths, &funixsize,
293 		    &funixmaxsize, _PATH_LOG);
294 	funix = (int *)malloc(sizeof(int) * funixsize);
295 	if (funix == NULL) {
296 		logerror("couldn't allocate funix descriptors");
297 		die(0);
298 	}
299 	for (j = 0, pp = LogPaths; *pp; pp++, j++) {
300 		unlink(*pp);
301 		memset(&sunx, 0, sizeof(sunx));
302 		sunx.sun_family = AF_LOCAL;
303 		(void)strncpy(sunx.sun_path, *pp, sizeof(sunx.sun_path));
304 		funix[j] = socket(AF_LOCAL, SOCK_DGRAM, 0);
305 		if (funix[j] < 0 || bind(funix[j],
306 		    (struct sockaddr *)&sunx, SUN_LEN(&sunx)) < 0 ||
307 		    chmod(*pp, 0666) < 0) {
308 			int serrno = errno;
309 			(void)snprintf(line, sizeof line,
310 			    "cannot create %s", *pp);
311 			errno = serrno;
312 			logerror(line);
313 			errno = serrno;
314 			dprintf("cannot create %s (%d)\n", *pp, errno);
315 			die(0);
316 		}
317 		dprintf("listening on unix dgram socket %s\n", *pp);
318 	}
319 
320 	if (!SecureMode)
321 		finet = socket(AF_INET, SOCK_DGRAM, 0);
322 	else
323 		finet = -1;
324 
325 	if (finet >= 0) {
326 		struct servent *sp;
327 
328 		sp = getservbyname("syslog", "udp");
329 		if (sp == NULL) {
330 			errno = 0;
331 			logerror("syslog/udp: unknown service");
332 			die(0);
333 		}
334 		memset(&sin, 0, sizeof(sin));
335 		sin.sin_family = AF_INET;
336 		sin.sin_port = LogPort = sp->s_port;
337 		if (bind(finet, (struct sockaddr *)&sin, sizeof(sin)) < 0) {
338 			logerror("bind");
339 			if (!Debug)
340 				die(0);
341 		} else {
342 			InetInuse = 1;
343 		}
344 		dprintf("listening on inet socket\n");
345 	}
346 	if ((fklog = open(_PATH_KLOG, O_RDONLY, 0)) < 0) {
347 		dprintf("can't open %s (%d)\n", _PATH_KLOG, errno);
348 	} else {
349 		dprintf("listening on kernel log %s\n", _PATH_KLOG);
350 	}
351 
352 	/* tuck my process id away, if i'm not in debug mode */
353 	if (Debug == 0)
354 		pidfile(NULL);
355 
356 	dprintf("off & running....\n");
357 
358 	init(0);
359 	(void)signal(SIGHUP, init);
360 
361 	/* setup pollfd set. */
362 	readfds = (struct pollfd *)malloc(sizeof(struct pollfd) *
363 					  (funixsize + 2));
364 	if (readfds == NULL) {
365 		logerror("couldn't allocate pollfds");
366 		die(0);
367 	}
368 	nfds = 0;
369 	if (fklog >= 0) {
370 		nfklogix = nfds++;
371 		readfds[nfklogix].fd = fklog;
372 		readfds[nfklogix].events = POLLIN | POLLPRI;
373 	}
374 	if (finet >= 0) {
375 		nfinetix = nfds++;
376 		readfds[nfinetix].fd = finet;
377 		readfds[nfinetix].events = POLLIN | POLLPRI;
378 	}
379 	nfunixbaseix = nfds;
380 	for (j = 0, pp = LogPaths; *pp; pp++) {
381 		readfds[nfds].fd = funix[j++];
382 		readfds[nfds++].events = POLLIN | POLLPRI;
383 	}
384 
385 	for (;;) {
386 		int rv;
387 
388 		rv = poll(readfds, nfds, INFTIM);
389 		if (rv == 0)
390 			continue;
391 		if (rv < 0) {
392 			if (errno != EINTR)
393 				logerror("poll");
394 			continue;
395 		}
396 		dprintf("got a message (%d)\n", rv);
397 		if (fklog >= 0 &&
398 		    (readfds[nfklogix].revents & (POLLIN | POLLPRI))) {
399 			dprintf("kernel log active\n");
400 			i = read(fklog, line, linesize - 1);
401 			if (i > 0) {
402 				line[i] = '\0';
403 				printsys(line);
404 			} else if (i < 0 && errno != EINTR) {
405 				logerror("klog");
406 				fklog = -1;
407 			}
408 		}
409 		for (j = 0, pp = LogPaths; *pp; pp++, j++) {
410 			if ((readfds[nfunixbaseix + j].revents &
411 			    (POLLIN | POLLPRI)) == 0)
412 				continue;
413 
414 			dprintf("unix socket (%s) active\n", *pp);
415 			len = sizeof(fromunix);
416 			i = recvfrom(funix[j], line, MAXLINE, 0,
417 			    (struct sockaddr *)&fromunix, &len);
418 			if (i > 0) {
419 				line[i] = '\0';
420 				printline(LocalHostName, line);
421 			} else if (i < 0 && errno != EINTR) {
422 				char buf[MAXPATHLEN];
423 				int serrno = errno;
424 
425 				(void)snprintf(buf, sizeof buf,
426 				    "recvfrom unix %s", *pp);
427 				errno = serrno;
428 				logerror(buf);
429 			}
430 		}
431 		if (finet >= 0 &&
432 		    (readfds[nfinetix].revents & (POLLIN | POLLPRI))) {
433 			dprintf("inet socket active\n");
434 			len = sizeof(frominet);
435 			i = recvfrom(finet, line, MAXLINE, 0,
436 			    (struct sockaddr *)&frominet, &len);
437 			if (i > 0) {
438 				line[i] = '\0';
439 				printline(cvthname(&frominet), line);
440 			} else if (i < 0 && errno != EINTR)
441 				logerror("recvfrom inet");
442 		}
443 	}
444 }
445 
446 void
447 usage()
448 {
449 
450 	(void)fprintf(stderr,
451 	    "usage: syslogd [-f conffile] [-m markinterval] [-p logpath1] [-p logpath2 ..]\n");
452 	exit(1);
453 }
454 
455 /*
456  * given a pointer to an array of char *'s, a pointer to it's current
457  * size and current allocated max size, and a new char * to add, add
458  * it, update everything as necessary, possibly allocating a new array
459  */
460 void
461 logpath_add(lp, szp, maxszp, new)
462 	char ***lp;
463 	int *szp;
464 	int *maxszp;
465 	char *new;
466 {
467 
468 	if (*szp == *maxszp) {
469 		if (*maxszp == 0) {
470 			*maxszp = 4;	/* start of with enough for now */
471 			*lp = NULL;
472 		}
473 		else
474 			*maxszp *= 2;
475 		*lp = realloc(*lp, sizeof(char *) * (*maxszp + 1));
476 		if (*lp == NULL) {
477 			logerror("couldn't allocate line buffer");
478 			die(0);
479 		}
480 	}
481 	(*lp)[(*szp)++] = new;
482 	(*lp)[(*szp)] = NULL;		/* always keep it NULL terminated */
483 }
484 
485 /* do a file of log sockets */
486 void
487 logpath_fileadd(lp, szp, maxszp, file)
488 	char ***lp;
489 	int *szp;
490 	int *maxszp;
491 	char *file;
492 {
493 	FILE *fp;
494 	char *line;
495 	size_t len;
496 
497 	fp = fopen(file, "r");
498 	if (fp == NULL) {
499 		int serrno = errno;
500 
501 		dprintf("can't open %s (%d)\n", file, errno);
502 		errno = serrno;
503 		logerror("could not open socket file list");
504 		die(0);
505 	}
506 
507 	while ((line = fgetln(fp, &len))) {
508 		line[len - 1] = 0;
509 		logpath_add(lp, szp, maxszp, line);
510 	}
511 	fclose(fp);
512 }
513 
514 /*
515  * Take a raw input line, decode the message, and print the message
516  * on the appropriate log files.
517  */
518 void
519 printline(hname, msg)
520 	char *hname;
521 	char *msg;
522 {
523 	int c, pri;
524 	char *p, *q, line[MAXLINE + 1];
525 
526 	/* test for special codes */
527 	pri = DEFUPRI;
528 	p = msg;
529 	if (*p == '<') {
530 		pri = 0;
531 		while (isdigit(*++p))
532 			pri = 10 * pri + (*p - '0');
533 		if (*p == '>')
534 			++p;
535 	}
536 	if (pri &~ (LOG_FACMASK|LOG_PRIMASK))
537 		pri = DEFUPRI;
538 
539 	/* don't allow users to log kernel messages */
540 	if (LOG_FAC(pri) == LOG_KERN)
541 		pri = LOG_MAKEPRI(LOG_USER, LOG_PRI(pri));
542 
543 	q = line;
544 
545 	while ((c = *p++ & 0177) != '\0' &&
546 	    q < &line[sizeof(line) - 1])
547 		if (iscntrl(c))
548 			if (c == '\n')
549 				*q++ = ' ';
550 			else if (c == '\t')
551 				*q++ = '\t';
552 			else {
553 				*q++ = '^';
554 				*q++ = c ^ 0100;
555 			}
556 		else
557 			*q++ = c;
558 	*q = '\0';
559 
560 	logmsg(pri, line, hname, 0);
561 }
562 
563 /*
564  * Take a raw input line from /dev/klog, split and format similar to syslog().
565  */
566 void
567 printsys(msg)
568 	char *msg;
569 {
570 	int c, pri, flags;
571 	char *lp, *p, *q, line[MAXLINE + 1];
572 
573 	(void)strcpy(line, _PATH_UNIX);
574 	(void)strcat(line, ": ");
575 	lp = line + strlen(line);
576 	for (p = msg; *p != '\0'; ) {
577 		flags = SYNC_FILE | ADDDATE;	/* fsync file after write */
578 		pri = DEFSPRI;
579 		if (*p == '<') {
580 			pri = 0;
581 			while (isdigit(*++p))
582 				pri = 10 * pri + (*p - '0');
583 			if (*p == '>')
584 				++p;
585 		} else {
586 			/* kernel printf's come out on console */
587 			flags |= IGN_CONS;
588 		}
589 		if (pri &~ (LOG_FACMASK|LOG_PRIMASK))
590 			pri = DEFSPRI;
591 		q = lp;
592 		while (*p != '\0' && (c = *p++) != '\n' &&
593 		    q < &line[MAXLINE])
594 			*q++ = c;
595 		*q = '\0';
596 		logmsg(pri, line, LocalHostName, flags);
597 	}
598 }
599 
600 time_t	now;
601 
602 /*
603  * Log a message to the appropriate log files, users, etc. based on
604  * the priority.
605  */
606 void
607 logmsg(pri, msg, from, flags)
608 	int pri;
609 	char *msg, *from;
610 	int flags;
611 {
612 	struct filed *f;
613 	int fac, msglen, omask, prilev;
614 	char *timestamp;
615 
616 	dprintf("logmsg: pri 0%o, flags 0x%x, from %s, msg %s\n",
617 	    pri, flags, from, msg);
618 
619 	omask = sigblock(sigmask(SIGHUP)|sigmask(SIGALRM));
620 
621 	/*
622 	 * Check to see if msg looks non-standard.
623 	 */
624 	msglen = strlen(msg);
625 	if (msglen < 16 || msg[3] != ' ' || msg[6] != ' ' ||
626 	    msg[9] != ':' || msg[12] != ':' || msg[15] != ' ')
627 		flags |= ADDDATE;
628 
629 	(void)time(&now);
630 	if (flags & ADDDATE)
631 		timestamp = ctime(&now) + 4;
632 	else {
633 		timestamp = msg;
634 		msg += 16;
635 		msglen -= 16;
636 	}
637 
638 	/* extract facility and priority level */
639 	if (flags & MARK)
640 		fac = LOG_NFACILITIES;
641 	else
642 		fac = LOG_FAC(pri);
643 	prilev = LOG_PRI(pri);
644 
645 	/* log the message to the particular outputs */
646 	if (!Initialized) {
647 		f = &consfile;
648 		f->f_file = open(ctty, O_WRONLY, 0);
649 
650 		if (f->f_file >= 0) {
651 			fprintlog(f, flags, msg);
652 			(void)close(f->f_file);
653 		}
654 		(void)sigsetmask(omask);
655 		return;
656 	}
657 	for (f = Files; f; f = f->f_next) {
658 		/* skip messages that are incorrect priority */
659 		if (f->f_pmask[fac] < prilev ||
660 		    f->f_pmask[fac] == INTERNAL_NOPRI)
661 			continue;
662 
663 		if (f->f_type == F_CONSOLE && (flags & IGN_CONS))
664 			continue;
665 
666 		/* don't output marks to recently written files */
667 		if ((flags & MARK) && (now - f->f_time) < MarkInterval / 2)
668 			continue;
669 
670 		/*
671 		 * suppress duplicate lines to this file
672 		 */
673 		if ((flags & MARK) == 0 && msglen == f->f_prevlen &&
674 		    !strcmp(msg, f->f_prevline) &&
675 		    !strcmp(from, f->f_prevhost)) {
676 			(void)strncpy(f->f_lasttime, timestamp, 15);
677 			f->f_prevcount++;
678 			dprintf("msg repeated %d times, %ld sec of %d\n",
679 			    f->f_prevcount, (long)(now - f->f_time),
680 			    repeatinterval[f->f_repeatcount]);
681 			/*
682 			 * If domark would have logged this by now,
683 			 * flush it now (so we don't hold isolated messages),
684 			 * but back off so we'll flush less often
685 			 * in the future.
686 			 */
687 			if (now > REPEATTIME(f)) {
688 				fprintlog(f, flags, (char *)NULL);
689 				BACKOFF(f);
690 			}
691 		} else {
692 			/* new line, save it */
693 			if (f->f_prevcount)
694 				fprintlog(f, 0, (char *)NULL);
695 			f->f_repeatcount = 0;
696 			f->f_prevpri = pri;
697 			(void)strncpy(f->f_lasttime, timestamp, 15);
698 			(void)strncpy(f->f_prevhost, from,
699 					sizeof(f->f_prevhost));
700 			if (msglen < MAXSVLINE) {
701 				f->f_prevlen = msglen;
702 				(void)strcpy(f->f_prevline, msg);
703 				fprintlog(f, flags, (char *)NULL);
704 			} else {
705 				f->f_prevline[0] = 0;
706 				f->f_prevlen = 0;
707 				fprintlog(f, flags, msg);
708 			}
709 		}
710 	}
711 	(void)sigsetmask(omask);
712 }
713 
714 void
715 fprintlog(f, flags, msg)
716 	struct filed *f;
717 	int flags;
718 	char *msg;
719 {
720 	struct iovec iov[6];
721 	struct iovec *v;
722 	int l;
723 	char line[MAXLINE + 1], repbuf[80], greetings[200];
724 
725 	v = iov;
726 	if (f->f_type == F_WALL) {
727 		v->iov_base = greetings;
728 		v->iov_len = snprintf(greetings, sizeof greetings,
729 		    "\r\n\7Message from syslogd@%s at %.24s ...\r\n",
730 		    f->f_prevhost, ctime(&now));
731 		v++;
732 		v->iov_base = "";
733 		v->iov_len = 0;
734 		v++;
735 	} else {
736 		v->iov_base = f->f_lasttime;
737 		v->iov_len = 15;
738 		v++;
739 		v->iov_base = " ";
740 		v->iov_len = 1;
741 		v++;
742 	}
743 	v->iov_base = f->f_prevhost;
744 	v->iov_len = strlen(v->iov_base);
745 	v++;
746 	v->iov_base = " ";
747 	v->iov_len = 1;
748 	v++;
749 
750 	if (msg) {
751 		v->iov_base = msg;
752 		v->iov_len = strlen(msg);
753 	} else if (f->f_prevcount > 1) {
754 		v->iov_base = repbuf;
755 		v->iov_len = snprintf(repbuf, sizeof repbuf,
756 		    "last message repeated %d times", f->f_prevcount);
757 	} else {
758 		v->iov_base = f->f_prevline;
759 		v->iov_len = f->f_prevlen;
760 	}
761 	v++;
762 
763 	dprintf("Logging to %s", TypeNames[f->f_type]);
764 	f->f_time = now;
765 
766 	switch (f->f_type) {
767 	case F_UNUSED:
768 		dprintf("\n");
769 		break;
770 
771 	case F_FORW:
772 		dprintf(" %s\n", f->f_un.f_forw.f_hname);
773 		/* check for local vs remote messages (from FreeBSD PR#bin/7055) */
774 		if (strcmp(f->f_prevhost, LocalHostName)) {
775 			l = snprintf(line, sizeof(line) - 1,
776 				     "<%d>%.15s [%s]: %s",
777 				     f->f_prevpri, (char *) iov[0].iov_base,
778 				     f->f_prevhost, (char *) iov[4].iov_base);
779 		} else {
780 			l = snprintf(line, sizeof(line) - 1, "<%d>%.15s %s",
781 				     f->f_prevpri, (char *) iov[0].iov_base,
782 				     (char *) iov[4].iov_base);
783 		}
784 		if (l > MAXLINE)
785 			l = MAXLINE;
786 		if ((finet >= 0) &&
787 		     (sendto(finet, line, l, 0,
788 			     (struct sockaddr *)&f->f_un.f_forw.f_addr,
789 			     sizeof(f->f_un.f_forw.f_addr)) != l)) {
790 			int e = errno;
791 			f->f_type = F_UNUSED;
792 			errno = e;
793 			logerror("sendto");
794 		}
795 		break;
796 
797 	case F_CONSOLE:
798 		if (flags & IGN_CONS) {
799 			dprintf(" (ignored)\n");
800 			break;
801 		}
802 		/* FALLTHROUGH */
803 
804 	case F_TTY:
805 	case F_FILE:
806 		dprintf(" %s\n", f->f_un.f_fname);
807 		if (f->f_type != F_FILE) {
808 			v->iov_base = "\r\n";
809 			v->iov_len = 2;
810 		} else {
811 			v->iov_base = "\n";
812 			v->iov_len = 1;
813 		}
814 	again:
815 		if (writev(f->f_file, iov, 6) < 0) {
816 			int e = errno;
817 			(void)close(f->f_file);
818 			/*
819 			 * Check for errors on TTY's due to loss of tty
820 			 */
821 			if ((e == EIO || e == EBADF) && f->f_type != F_FILE) {
822 				f->f_file = open(f->f_un.f_fname,
823 				    O_WRONLY|O_APPEND, 0);
824 				if (f->f_file < 0) {
825 					f->f_type = F_UNUSED;
826 					logerror(f->f_un.f_fname);
827 				} else
828 					goto again;
829 			} else {
830 				f->f_type = F_UNUSED;
831 				errno = e;
832 				logerror(f->f_un.f_fname);
833 			}
834 		} else if (flags & SYNC_FILE)
835 			(void)fsync(f->f_file);
836 		break;
837 
838 	case F_USERS:
839 	case F_WALL:
840 		dprintf("\n");
841 		v->iov_base = "\r\n";
842 		v->iov_len = 2;
843 		wallmsg(f, iov);
844 		break;
845 	}
846 	f->f_prevcount = 0;
847 }
848 
849 /*
850  *  WALLMSG -- Write a message to the world at large
851  *
852  *	Write the specified message to either the entire
853  *	world, or a list of approved users.
854  */
855 void
856 wallmsg(f, iov)
857 	struct filed *f;
858 	struct iovec *iov;
859 {
860 	static int reenter;			/* avoid calling ourselves */
861 	FILE *uf;
862 	struct utmp ut;
863 	int i;
864 	char *p;
865 	char line[sizeof(ut.ut_line) + 1];
866 
867 	if (reenter++)
868 		return;
869 	if ((uf = fopen(_PATH_UTMP, "r")) == NULL) {
870 		logerror(_PATH_UTMP);
871 		reenter = 0;
872 		return;
873 	}
874 	/* NOSTRICT */
875 	while (fread((char *)&ut, sizeof(ut), 1, uf) == 1) {
876 		if (ut.ut_name[0] == '\0')
877 			continue;
878 		strncpy(line, ut.ut_line, sizeof(ut.ut_line));
879 		line[sizeof(ut.ut_line)] = '\0';
880 		if (f->f_type == F_WALL) {
881 			if ((p = ttymsg(iov, 6, line, TTYMSGTIME)) != NULL) {
882 				errno = 0;	/* already in msg */
883 				logerror(p);
884 			}
885 			continue;
886 		}
887 		/* should we send the message to this user? */
888 		for (i = 0; i < MAXUNAMES; i++) {
889 			if (!f->f_un.f_uname[i][0])
890 				break;
891 			if (!strncmp(f->f_un.f_uname[i], ut.ut_name,
892 			    UT_NAMESIZE)) {
893 				if ((p = ttymsg(iov, 6, line, TTYMSGTIME))
894 								!= NULL) {
895 					errno = 0;	/* already in msg */
896 					logerror(p);
897 				}
898 				break;
899 			}
900 		}
901 	}
902 	(void)fclose(uf);
903 	reenter = 0;
904 }
905 
906 void
907 reapchild(signo)
908 	int signo;
909 {
910 	union wait status;
911 
912 	while (wait3((int *)&status, WNOHANG, (struct rusage *)NULL) > 0)
913 		;
914 }
915 
916 /*
917  * Return a printable representation of a host address.
918  */
919 char *
920 cvthname(f)
921 	struct sockaddr_in *f;
922 {
923 	struct hostent *hp;
924 	char *p;
925 
926 	dprintf("cvthname(%s)\n", inet_ntoa(f->sin_addr));
927 
928 	if (f->sin_family != AF_INET) {
929 		dprintf("Malformed from address\n");
930 		return ("???");
931 	}
932 	hp = gethostbyaddr((char *)&f->sin_addr,
933 	    sizeof(struct in_addr), f->sin_family);
934 	if (hp == 0) {
935 		dprintf("Host name for your address (%s) unknown\n",
936 			inet_ntoa(f->sin_addr));
937 		return (inet_ntoa(f->sin_addr));
938 	}
939 	if ((p = strchr(hp->h_name, '.')) && strcmp(p + 1, LocalDomain) == 0)
940 		*p = '\0';
941 	return (hp->h_name);
942 }
943 
944 void
945 domark(signo)
946 	int signo;
947 {
948 	struct filed *f;
949 
950 	now = time((time_t *)NULL);
951 	MarkSeq += TIMERINTVL;
952 	if (MarkSeq >= MarkInterval) {
953 		logmsg(LOG_INFO, "-- MARK --", LocalHostName, ADDDATE|MARK);
954 		MarkSeq = 0;
955 	}
956 
957 	for (f = Files; f; f = f->f_next) {
958 		if (f->f_prevcount && now >= REPEATTIME(f)) {
959 			dprintf("flush %s: repeated %d times, %d sec.\n",
960 			    TypeNames[f->f_type], f->f_prevcount,
961 			    repeatinterval[f->f_repeatcount]);
962 			fprintlog(f, 0, (char *)NULL);
963 			BACKOFF(f);
964 		}
965 	}
966 	(void)alarm(TIMERINTVL);
967 }
968 
969 /*
970  * Print syslogd errors some place.
971  */
972 void
973 logerror(type)
974 	char *type;
975 {
976 	char buf[100];
977 
978 	if (errno)
979 		(void)snprintf(buf,
980 		    sizeof(buf), "syslogd: %s: %s", type, strerror(errno));
981 	else
982 		(void)snprintf(buf, sizeof(buf), "syslogd: %s", type);
983 	errno = 0;
984 	dprintf("%s\n", buf);
985 	logmsg(LOG_SYSLOG|LOG_ERR, buf, LocalHostName, ADDDATE);
986 }
987 
988 void
989 die(signo)
990 	int signo;
991 {
992 	struct filed *f;
993 	char buf[100], **p;
994 
995 	for (f = Files; f != NULL; f = f->f_next) {
996 		/* flush any pending output */
997 		if (f->f_prevcount)
998 			fprintlog(f, 0, (char *)NULL);
999 	}
1000 	if (signo) {
1001 		dprintf("syslogd: exiting on signal %d\n", signo);
1002 		(void)snprintf(buf, sizeof buf, "exiting on signal %d", signo);
1003 		errno = 0;
1004 		logerror(buf);
1005 	}
1006 	for (p = LogPaths; p && *p; p++)
1007 		unlink(*p);
1008 	exit(0);
1009 }
1010 
1011 /*
1012  *  INIT -- Initialize syslogd from configuration table
1013  */
1014 void
1015 init(signo)
1016 	int signo;
1017 {
1018 	int i;
1019 	FILE *cf;
1020 	struct filed *f, *next, **nextp;
1021 	char *p;
1022 	char cline[LINE_MAX];
1023 
1024 	dprintf("init\n");
1025 
1026 	/*
1027 	 *  Close all open log files.
1028 	 */
1029 	Initialized = 0;
1030 	for (f = Files; f != NULL; f = next) {
1031 		/* flush any pending output */
1032 		if (f->f_prevcount)
1033 			fprintlog(f, 0, (char *)NULL);
1034 
1035 		switch (f->f_type) {
1036 		case F_FILE:
1037 		case F_TTY:
1038 		case F_CONSOLE:
1039 			(void)close(f->f_file);
1040 			break;
1041 		}
1042 		next = f->f_next;
1043 		free((char *)f);
1044 	}
1045 	Files = NULL;
1046 	nextp = &Files;
1047 
1048 	/* open the configuration file */
1049 	if ((cf = fopen(ConfFile, "r")) == NULL) {
1050 		dprintf("cannot open %s\n", ConfFile);
1051 		*nextp = (struct filed *)calloc(1, sizeof(*f));
1052 		cfline("*.ERR\t/dev/console", *nextp);
1053 		(*nextp)->f_next = (struct filed *)calloc(1, sizeof(*f));
1054 		cfline("*.PANIC\t*", (*nextp)->f_next);
1055 		Initialized = 1;
1056 		return;
1057 	}
1058 
1059 	/*
1060 	 *  Foreach line in the conf table, open that file.
1061 	 */
1062 	f = NULL;
1063 	while (fgets(cline, sizeof(cline), cf) != NULL) {
1064 		/*
1065 		 * check for end-of-section, comments, strip off trailing
1066 		 * spaces and newline character.
1067 		 */
1068 		for (p = cline; isspace(*p); ++p)
1069 			continue;
1070 		if (*p == '\0' || *p == '#')
1071 			continue;
1072 		for (p = strchr(cline, '\0'); isspace(*--p);)
1073 			continue;
1074 		*++p = '\0';
1075 		f = (struct filed *)calloc(1, sizeof(*f));
1076 		*nextp = f;
1077 		nextp = &f->f_next;
1078 		cfline(cline, f);
1079 	}
1080 
1081 	/* close the configuration file */
1082 	(void)fclose(cf);
1083 
1084 	Initialized = 1;
1085 
1086 	if (Debug) {
1087 		for (f = Files; f; f = f->f_next) {
1088 			for (i = 0; i <= LOG_NFACILITIES; i++)
1089 				if (f->f_pmask[i] == INTERNAL_NOPRI)
1090 					printf("X ");
1091 				else
1092 					printf("%d ", f->f_pmask[i]);
1093 			printf("%s: ", TypeNames[f->f_type]);
1094 			switch (f->f_type) {
1095 			case F_FILE:
1096 			case F_TTY:
1097 			case F_CONSOLE:
1098 				printf("%s", f->f_un.f_fname);
1099 				break;
1100 
1101 			case F_FORW:
1102 				printf("%s", f->f_un.f_forw.f_hname);
1103 				break;
1104 
1105 			case F_USERS:
1106 				for (i = 0; i < MAXUNAMES && *f->f_un.f_uname[i]; i++)
1107 					printf("%s, ", f->f_un.f_uname[i]);
1108 				break;
1109 			}
1110 			printf("\n");
1111 		}
1112 	}
1113 
1114 	logmsg(LOG_SYSLOG|LOG_INFO, "syslogd: restart", LocalHostName, ADDDATE);
1115 	dprintf("syslogd: restarted\n");
1116 }
1117 
1118 /*
1119  * Crack a configuration file line
1120  */
1121 void
1122 cfline(line, f)
1123 	char *line;
1124 	struct filed *f;
1125 {
1126 	struct hostent *hp;
1127 	int i, pri;
1128 	char *bp, *p, *q;
1129 	char buf[MAXLINE], ebuf[100];
1130 
1131 	dprintf("cfline(%s)\n", line);
1132 
1133 	errno = 0;	/* keep strerror() stuff out of logerror messages */
1134 
1135 	/* clear out file entry */
1136 	memset(f, 0, sizeof(*f));
1137 	for (i = 0; i <= LOG_NFACILITIES; i++)
1138 		f->f_pmask[i] = INTERNAL_NOPRI;
1139 
1140 	/* scan through the list of selectors */
1141 	for (p = line; *p && *p != '\t';) {
1142 
1143 		/* find the end of this facility name list */
1144 		for (q = p; *q && *q != '\t' && *q++ != '.'; )
1145 			continue;
1146 
1147 		/* collect priority name */
1148 		for (bp = buf; *q && !strchr("\t,;", *q); )
1149 			*bp++ = *q++;
1150 		*bp = '\0';
1151 
1152 		/* skip cruft */
1153 		while (strchr(", ;", *q))
1154 			q++;
1155 
1156 		/* decode priority name */
1157 		if (*buf == '*')
1158 			pri = LOG_PRIMASK + 1;
1159 		else {
1160 			pri = decode(buf, prioritynames);
1161 			if (pri < 0) {
1162 				(void)snprintf(ebuf, sizeof ebuf,
1163 				    "unknown priority name \"%s\"", buf);
1164 				logerror(ebuf);
1165 				return;
1166 			}
1167 		}
1168 
1169 		/* scan facilities */
1170 		while (*p && !strchr("\t.;", *p)) {
1171 			for (bp = buf; *p && !strchr("\t,;.", *p); )
1172 				*bp++ = *p++;
1173 			*bp = '\0';
1174 			if (*buf == '*')
1175 				for (i = 0; i < LOG_NFACILITIES; i++)
1176 					f->f_pmask[i] = pri;
1177 			else {
1178 				i = decode(buf, facilitynames);
1179 				if (i < 0) {
1180 					(void)snprintf(ebuf, sizeof ebuf,
1181 					    "unknown facility name \"%s\"",
1182 					    buf);
1183 					logerror(ebuf);
1184 					return;
1185 				}
1186 				f->f_pmask[i >> 3] = pri;
1187 			}
1188 			while (*p == ',' || *p == ' ')
1189 				p++;
1190 		}
1191 
1192 		p = q;
1193 	}
1194 
1195 	/* skip to action part */
1196 	while (*p == '\t')
1197 		p++;
1198 
1199 	switch (*p)
1200 	{
1201 	case '@':
1202 		if (!InetInuse)
1203 			break;
1204 		(void)strcpy(f->f_un.f_forw.f_hname, ++p);
1205 		hp = gethostbyname(p);
1206 		if (hp == NULL) {
1207 			extern int h_errno;
1208 
1209 			logerror((char *)hstrerror(h_errno));
1210 			break;
1211 		}
1212 		memset(&f->f_un.f_forw.f_addr, 0,
1213 			 sizeof(f->f_un.f_forw.f_addr));
1214 		f->f_un.f_forw.f_addr.sin_family = AF_INET;
1215 		f->f_un.f_forw.f_addr.sin_port = LogPort;
1216 		memmove(&f->f_un.f_forw.f_addr.sin_addr, hp->h_addr, hp->h_length);
1217 		f->f_type = F_FORW;
1218 		break;
1219 
1220 	case '/':
1221 		(void)strcpy(f->f_un.f_fname, p);
1222 		if ((f->f_file = open(p, O_WRONLY|O_APPEND, 0)) < 0) {
1223 			f->f_type = F_UNUSED;
1224 			logerror(p);
1225 			break;
1226 		}
1227 		if (isatty(f->f_file))
1228 			f->f_type = F_TTY;
1229 		else
1230 			f->f_type = F_FILE;
1231 		if (strcmp(p, ctty) == 0)
1232 			f->f_type = F_CONSOLE;
1233 		break;
1234 
1235 	case '*':
1236 		f->f_type = F_WALL;
1237 		break;
1238 
1239 	default:
1240 		for (i = 0; i < MAXUNAMES && *p; i++) {
1241 			for (q = p; *q && *q != ','; )
1242 				q++;
1243 			(void)strncpy(f->f_un.f_uname[i], p, UT_NAMESIZE);
1244 			if ((q - p) > UT_NAMESIZE)
1245 				f->f_un.f_uname[i][UT_NAMESIZE] = '\0';
1246 			else
1247 				f->f_un.f_uname[i][q - p] = '\0';
1248 			while (*q == ',' || *q == ' ')
1249 				q++;
1250 			p = q;
1251 		}
1252 		f->f_type = F_USERS;
1253 		break;
1254 	}
1255 }
1256 
1257 
1258 /*
1259  *  Decode a symbolic name to a numeric value
1260  */
1261 int
1262 decode(name, codetab)
1263 	const char *name;
1264 	CODE *codetab;
1265 {
1266 	CODE *c;
1267 	char *p, buf[40];
1268 
1269 	if (isdigit(*name))
1270 		return (atoi(name));
1271 
1272 	for (p = buf; *name && p < &buf[sizeof(buf) - 1]; p++, name++) {
1273 		if (isupper(*name))
1274 			*p = tolower(*name);
1275 		else
1276 			*p = *name;
1277 	}
1278 	*p = '\0';
1279 	for (c = codetab; c->c_name; c++)
1280 		if (!strcmp(buf, c->c_name))
1281 			return (c->c_val);
1282 
1283 	return (-1);
1284 }
1285 
1286 /*
1287  * Retrieve the size of the kernel message buffer, via sysctl.
1288  */
1289 int
1290 getmsgbufsize()
1291 {
1292 	int msgbufsize, mib[2];
1293 	size_t size;
1294 
1295 	mib[0] = CTL_KERN;
1296 	mib[1] = KERN_MSGBUFSIZE;
1297 	size = sizeof msgbufsize;
1298 	if (sysctl(mib, 2, &msgbufsize, &size, NULL, 0) == -1) {
1299 		dprintf("couldn't get kern.msgbufsize\n");
1300 		return (0);
1301 	}
1302 	return (msgbufsize);
1303 }
1304