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syslogd.c revision 1.11
      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 1.11 1997/06/29 18:57:45 christos 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/un.h>
     85 #include <sys/time.h>
     86 #include <sys/resource.h>
     87 
     88 #include <netinet/in.h>
     89 #include <netdb.h>
     90 #include <arpa/inet.h>
     91 
     92 #include <ctype.h>
     93 #include <errno.h>
     94 #include <fcntl.h>
     95 #include <setjmp.h>
     96 #include <signal.h>
     97 #include <stdio.h>
     98 #include <stdlib.h>
     99 #include <string.h>
    100 #include <unistd.h>
    101 #include <utmp.h>
    102 #include <util.h>
    103 #include "pathnames.h"
    104 
    105 #define SYSLOG_NAMES
    106 #include <sys/syslog.h>
    107 
    108 char	*LogName = _PATH_LOG;
    109 char	*ConfFile = _PATH_LOGCONF;
    110 char	*PidFile = _PATH_LOGPID;
    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 
    196 void	cfline __P((char *, struct filed *));
    197 char   *cvthname __P((struct sockaddr_in *));
    198 int	decode __P((const char *, CODE *));
    199 void	die __P((int));
    200 void	domark __P((int));
    201 void	fprintlog __P((struct filed *, int, char *));
    202 void	init __P((int));
    203 void	logerror __P((char *));
    204 void	logmsg __P((int, char *, char *, int));
    205 void	printline __P((char *, char *));
    206 void	printsys __P((char *));
    207 void	reapchild __P((int));
    208 void	usage __P((void));
    209 void	wallmsg __P((struct filed *, struct iovec *));
    210 int	main __P((int, char *[]));
    211 
    212 int
    213 main(argc, argv)
    214 	int argc;
    215 	char *argv[];
    216 {
    217 	int ch, funix, i, inetm, fklog, klogm, len;
    218 	struct sockaddr_un sunx, fromunix;
    219 	struct sockaddr_in sin, frominet;
    220 	FILE *fp;
    221 	char *p, line[MSG_BSIZE + 1];
    222 
    223 	while ((ch = getopt(argc, argv, "dsf:m:p:")) != EOF)
    224 		switch(ch) {
    225 		case 'd':		/* debug */
    226 			Debug++;
    227 			break;
    228 		case 'f':		/* configuration file */
    229 			ConfFile = optarg;
    230 			break;
    231 		case 'm':		/* mark interval */
    232 			MarkInterval = atoi(optarg) * 60;
    233 			break;
    234 		case 'p':		/* path */
    235 			LogName = optarg;
    236 			break;
    237 		case 's':		/* no network mode */
    238 			SecureMode++;
    239 			break;
    240 		case '?':
    241 		default:
    242 			usage();
    243 		}
    244 	if ((argc -= optind) != 0)
    245 		usage();
    246 
    247 	if (!Debug)
    248 		(void)daemon(0, 0);
    249 	else
    250 		setlinebuf(stdout);
    251 
    252 	consfile.f_type = F_CONSOLE;
    253 	(void)strcpy(consfile.f_un.f_fname, ctty);
    254 	(void)gethostname(LocalHostName, sizeof(LocalHostName));
    255 	if ((p = strchr(LocalHostName, '.')) != NULL) {
    256 		*p++ = '\0';
    257 		LocalDomain = p;
    258 	} else
    259 		LocalDomain = "";
    260 	(void)signal(SIGTERM, die);
    261 	(void)signal(SIGINT, Debug ? die : SIG_IGN);
    262 	(void)signal(SIGQUIT, Debug ? die : SIG_IGN);
    263 	(void)signal(SIGCHLD, reapchild);
    264 	(void)signal(SIGALRM, domark);
    265 	(void)alarm(TIMERINTVL);
    266 	(void)unlink(LogName);
    267 
    268 #ifndef SUN_LEN
    269 #define SUN_LEN(unp) (strlen((unp)->sun_path) + 2)
    270 #endif
    271 	memset(&sunx, 0, sizeof(sunx));
    272 	sunx.sun_family = AF_UNIX;
    273 	(void)strncpy(sunx.sun_path, LogName, sizeof(sunx.sun_path));
    274 	funix = socket(AF_UNIX, SOCK_DGRAM, 0);
    275 	if (funix < 0 ||
    276 	    bind(funix, (struct sockaddr *)&sunx, SUN_LEN(&sunx)) < 0 ||
    277 	    chmod(LogName, 0666) < 0) {
    278 		(void) sprintf(line, "cannot create %s", LogName);
    279 		logerror(line);
    280 		dprintf("cannot create %s (%d)\n", LogName, errno);
    281 		die(0);
    282 	}
    283 
    284 	if (!SecureMode)
    285 		finet = socket(AF_INET, SOCK_DGRAM, 0);
    286 	else
    287 		finet = -1;
    288 
    289 	inetm = 0;
    290 	if (finet >= 0) {
    291 		struct servent *sp;
    292 
    293 		sp = getservbyname("syslog", "udp");
    294 		if (sp == NULL) {
    295 			errno = 0;
    296 			logerror("syslog/udp: unknown service");
    297 			die(0);
    298 		}
    299 		memset(&sin, 0, sizeof(sin));
    300 		sin.sin_family = AF_INET;
    301 		sin.sin_port = LogPort = sp->s_port;
    302 		if (bind(finet, (struct sockaddr *)&sin, sizeof(sin)) < 0) {
    303 			logerror("bind");
    304 			if (!Debug)
    305 				die(0);
    306 		} else {
    307 			inetm = FDMASK(finet);
    308 			InetInuse = 1;
    309 		}
    310 	}
    311 	if ((fklog = open(_PATH_KLOG, O_RDONLY, 0)) >= 0)
    312 		klogm = FDMASK(fklog);
    313 	else {
    314 		dprintf("can't open %s (%d)\n", _PATH_KLOG, errno);
    315 		klogm = 0;
    316 	}
    317 
    318 	/* tuck my process id away, if i'm not in debug mode */
    319 	if (Debug == 0) {
    320 		fp = fopen(PidFile, "w");
    321 		if (fp != NULL) {
    322 			fprintf(fp, "%d\n", getpid());
    323 			(void) fclose(fp);
    324 		}
    325 	}
    326 
    327 	dprintf("off & running....\n");
    328 
    329 	init(0);
    330 	(void)signal(SIGHUP, init);
    331 
    332 	for (;;) {
    333 		int nfds, readfds = FDMASK(funix) | inetm | klogm;
    334 
    335 		dprintf("readfds = %#x\n", readfds);
    336 		nfds = select(20, (fd_set *)&readfds, (fd_set *)NULL,
    337 		    (fd_set *)NULL, (struct timeval *)NULL);
    338 		if (nfds == 0)
    339 			continue;
    340 		if (nfds < 0) {
    341 			if (errno != EINTR)
    342 				logerror("select");
    343 			continue;
    344 		}
    345 		dprintf("got a message (%d, %#x)\n", nfds, readfds);
    346 		if (readfds & klogm) {
    347 			i = read(fklog, line, sizeof(line) - 1);
    348 			if (i > 0) {
    349 				line[i] = '\0';
    350 				printsys(line);
    351 			} else if (i < 0 && errno != EINTR) {
    352 				logerror("klog");
    353 				fklog = -1;
    354 				klogm = 0;
    355 			}
    356 		}
    357 		if (readfds & FDMASK(funix)) {
    358 			len = sizeof(fromunix);
    359 			i = recvfrom(funix, line, MAXLINE, 0,
    360 			    (struct sockaddr *)&fromunix, &len);
    361 			if (i > 0) {
    362 				line[i] = '\0';
    363 				printline(LocalHostName, line);
    364 			} else if (i < 0 && errno != EINTR)
    365 				logerror("recvfrom unix");
    366 		}
    367 		if (readfds & inetm) {
    368 			len = sizeof(frominet);
    369 			i = recvfrom(finet, line, MAXLINE, 0,
    370 			    (struct sockaddr *)&frominet, &len);
    371 			if (i > 0) {
    372 				line[i] = '\0';
    373 				printline(cvthname(&frominet), line);
    374 			} else if (i < 0 && errno != EINTR)
    375 				logerror("recvfrom inet");
    376 		}
    377 	}
    378 }
    379 
    380 void
    381 usage()
    382 {
    383 
    384 	(void)fprintf(stderr,
    385 	    "usage: syslogd [-f conffile] [-m markinterval] [-p logpath]\n");
    386 	exit(1);
    387 }
    388 
    389 /*
    390  * Take a raw input line, decode the message, and print the message
    391  * on the appropriate log files.
    392  */
    393 void
    394 printline(hname, msg)
    395 	char *hname;
    396 	char *msg;
    397 {
    398 	int c, pri;
    399 	char *p, *q, line[MAXLINE + 1];
    400 
    401 	/* test for special codes */
    402 	pri = DEFUPRI;
    403 	p = msg;
    404 	if (*p == '<') {
    405 		pri = 0;
    406 		while (isdigit(*++p))
    407 			pri = 10 * pri + (*p - '0');
    408 		if (*p == '>')
    409 			++p;
    410 	}
    411 	if (pri &~ (LOG_FACMASK|LOG_PRIMASK))
    412 		pri = DEFUPRI;
    413 
    414 	/* don't allow users to log kernel messages */
    415 	if (LOG_FAC(pri) == LOG_KERN)
    416 		pri = LOG_MAKEPRI(LOG_USER, LOG_PRI(pri));
    417 
    418 	q = line;
    419 
    420 	while ((c = *p++ & 0177) != '\0' &&
    421 	    q < &line[sizeof(line) - 1])
    422 		if (iscntrl(c))
    423 			if (c == '\n')
    424 				*q++ = ' ';
    425 			else if (c == '\t')
    426 				*q++ = '\t';
    427 			else {
    428 				*q++ = '^';
    429 				*q++ = c ^ 0100;
    430 			}
    431 		else
    432 			*q++ = c;
    433 	*q = '\0';
    434 
    435 	logmsg(pri, line, hname, 0);
    436 }
    437 
    438 /*
    439  * Take a raw input line from /dev/klog, split and format similar to syslog().
    440  */
    441 void
    442 printsys(msg)
    443 	char *msg;
    444 {
    445 	int c, pri, flags;
    446 	char *lp, *p, *q, line[MAXLINE + 1];
    447 
    448 	(void)strcpy(line, _PATH_UNIX);
    449 	(void)strcat(line, ": ");
    450 	lp = line + strlen(line);
    451 	for (p = msg; *p != '\0'; ) {
    452 		flags = SYNC_FILE | ADDDATE;	/* fsync file after write */
    453 		pri = DEFSPRI;
    454 		if (*p == '<') {
    455 			pri = 0;
    456 			while (isdigit(*++p))
    457 				pri = 10 * pri + (*p - '0');
    458 			if (*p == '>')
    459 				++p;
    460 		} else {
    461 			/* kernel printf's come out on console */
    462 			flags |= IGN_CONS;
    463 		}
    464 		if (pri &~ (LOG_FACMASK|LOG_PRIMASK))
    465 			pri = DEFSPRI;
    466 		q = lp;
    467 		while (*p != '\0' && (c = *p++) != '\n' &&
    468 		    q < &line[MAXLINE])
    469 			*q++ = c;
    470 		*q = '\0';
    471 		logmsg(pri, line, LocalHostName, flags);
    472 	}
    473 }
    474 
    475 time_t	now;
    476 
    477 /*
    478  * Log a message to the appropriate log files, users, etc. based on
    479  * the priority.
    480  */
    481 void
    482 logmsg(pri, msg, from, flags)
    483 	int pri;
    484 	char *msg, *from;
    485 	int flags;
    486 {
    487 	struct filed *f;
    488 	int fac, msglen, omask, prilev;
    489 	char *timestamp;
    490 
    491 	dprintf("logmsg: pri 0%o, flags 0x%x, from %s, msg %s\n",
    492 	    pri, flags, from, msg);
    493 
    494 	omask = sigblock(sigmask(SIGHUP)|sigmask(SIGALRM));
    495 
    496 	/*
    497 	 * Check to see if msg looks non-standard.
    498 	 */
    499 	msglen = strlen(msg);
    500 	if (msglen < 16 || msg[3] != ' ' || msg[6] != ' ' ||
    501 	    msg[9] != ':' || msg[12] != ':' || msg[15] != ' ')
    502 		flags |= ADDDATE;
    503 
    504 	(void)time(&now);
    505 	if (flags & ADDDATE)
    506 		timestamp = ctime(&now) + 4;
    507 	else {
    508 		timestamp = msg;
    509 		msg += 16;
    510 		msglen -= 16;
    511 	}
    512 
    513 	/* extract facility and priority level */
    514 	if (flags & MARK)
    515 		fac = LOG_NFACILITIES;
    516 	else
    517 		fac = LOG_FAC(pri);
    518 	prilev = LOG_PRI(pri);
    519 
    520 	/* log the message to the particular outputs */
    521 	if (!Initialized) {
    522 		f = &consfile;
    523 		f->f_file = open(ctty, O_WRONLY, 0);
    524 
    525 		if (f->f_file >= 0) {
    526 			fprintlog(f, flags, msg);
    527 			(void)close(f->f_file);
    528 		}
    529 		(void)sigsetmask(omask);
    530 		return;
    531 	}
    532 	for (f = Files; f; f = f->f_next) {
    533 		/* skip messages that are incorrect priority */
    534 		if (f->f_pmask[fac] < prilev ||
    535 		    f->f_pmask[fac] == INTERNAL_NOPRI)
    536 			continue;
    537 
    538 		if (f->f_type == F_CONSOLE && (flags & IGN_CONS))
    539 			continue;
    540 
    541 		/* don't output marks to recently written files */
    542 		if ((flags & MARK) && (now - f->f_time) < MarkInterval / 2)
    543 			continue;
    544 
    545 		/*
    546 		 * suppress duplicate lines to this file
    547 		 */
    548 		if ((flags & MARK) == 0 && msglen == f->f_prevlen &&
    549 		    !strcmp(msg, f->f_prevline) &&
    550 		    !strcmp(from, f->f_prevhost)) {
    551 			(void)strncpy(f->f_lasttime, timestamp, 15);
    552 			f->f_prevcount++;
    553 			dprintf("msg repeated %d times, %ld sec of %d\n",
    554 			    f->f_prevcount, now - f->f_time,
    555 			    repeatinterval[f->f_repeatcount]);
    556 			/*
    557 			 * If domark would have logged this by now,
    558 			 * flush it now (so we don't hold isolated messages),
    559 			 * but back off so we'll flush less often
    560 			 * in the future.
    561 			 */
    562 			if (now > REPEATTIME(f)) {
    563 				fprintlog(f, flags, (char *)NULL);
    564 				BACKOFF(f);
    565 			}
    566 		} else {
    567 			/* new line, save it */
    568 			if (f->f_prevcount)
    569 				fprintlog(f, 0, (char *)NULL);
    570 			f->f_repeatcount = 0;
    571 			f->f_prevpri = pri;
    572 			(void)strncpy(f->f_lasttime, timestamp, 15);
    573 			(void)strncpy(f->f_prevhost, from,
    574 					sizeof(f->f_prevhost));
    575 			if (msglen < MAXSVLINE) {
    576 				f->f_prevlen = msglen;
    577 				(void)strcpy(f->f_prevline, msg);
    578 				fprintlog(f, flags, (char *)NULL);
    579 			} else {
    580 				f->f_prevline[0] = 0;
    581 				f->f_prevlen = 0;
    582 				fprintlog(f, flags, msg);
    583 			}
    584 		}
    585 	}
    586 	(void)sigsetmask(omask);
    587 }
    588 
    589 void
    590 fprintlog(f, flags, msg)
    591 	struct filed *f;
    592 	int flags;
    593 	char *msg;
    594 {
    595 	struct iovec iov[6];
    596 	struct iovec *v;
    597 	int l;
    598 	char line[MAXLINE + 1], repbuf[80], greetings[200];
    599 
    600 	v = iov;
    601 	if (f->f_type == F_WALL) {
    602 		v->iov_base = greetings;
    603 		v->iov_len = sprintf(greetings,
    604 		    "\r\n\7Message from syslogd@%s at %.24s ...\r\n",
    605 		    f->f_prevhost, ctime(&now));
    606 		v++;
    607 		v->iov_base = "";
    608 		v->iov_len = 0;
    609 		v++;
    610 	} else {
    611 		v->iov_base = f->f_lasttime;
    612 		v->iov_len = 15;
    613 		v++;
    614 		v->iov_base = " ";
    615 		v->iov_len = 1;
    616 		v++;
    617 	}
    618 	v->iov_base = f->f_prevhost;
    619 	v->iov_len = strlen(v->iov_base);
    620 	v++;
    621 	v->iov_base = " ";
    622 	v->iov_len = 1;
    623 	v++;
    624 
    625 	if (msg) {
    626 		v->iov_base = msg;
    627 		v->iov_len = strlen(msg);
    628 	} else if (f->f_prevcount > 1) {
    629 		v->iov_base = repbuf;
    630 		v->iov_len = sprintf(repbuf, "last message repeated %d times",
    631 		    f->f_prevcount);
    632 	} else {
    633 		v->iov_base = f->f_prevline;
    634 		v->iov_len = f->f_prevlen;
    635 	}
    636 	v++;
    637 
    638 	dprintf("Logging to %s", TypeNames[f->f_type]);
    639 	f->f_time = now;
    640 
    641 	switch (f->f_type) {
    642 	case F_UNUSED:
    643 		dprintf("\n");
    644 		break;
    645 
    646 	case F_FORW:
    647 		dprintf(" %s\n", f->f_un.f_forw.f_hname);
    648 		l = sprintf(line, "<%d>%.15s %s", f->f_prevpri,
    649 		    iov[0].iov_base, iov[4].iov_base);
    650 		if (l > MAXLINE)
    651 			l = MAXLINE;
    652 		if ((finet >= 0) &&
    653 		     (sendto(finet, line, l, 0,
    654 			     (struct sockaddr *)&f->f_un.f_forw.f_addr,
    655 			     sizeof(f->f_un.f_forw.f_addr)) != l)) {
    656 			int e = errno;
    657 			(void)close(f->f_file);
    658 			f->f_type = F_UNUSED;
    659 			errno = e;
    660 			logerror("sendto");
    661 		}
    662 		break;
    663 
    664 	case F_CONSOLE:
    665 		if (flags & IGN_CONS) {
    666 			dprintf(" (ignored)\n");
    667 			break;
    668 		}
    669 		/* FALLTHROUGH */
    670 
    671 	case F_TTY:
    672 	case F_FILE:
    673 		dprintf(" %s\n", f->f_un.f_fname);
    674 		if (f->f_type != F_FILE) {
    675 			v->iov_base = "\r\n";
    676 			v->iov_len = 2;
    677 		} else {
    678 			v->iov_base = "\n";
    679 			v->iov_len = 1;
    680 		}
    681 	again:
    682 		if (writev(f->f_file, iov, 6) < 0) {
    683 			int e = errno;
    684 			(void)close(f->f_file);
    685 			/*
    686 			 * Check for errors on TTY's due to loss of tty
    687 			 */
    688 			if ((e == EIO || e == EBADF) && f->f_type != F_FILE) {
    689 				f->f_file = open(f->f_un.f_fname,
    690 				    O_WRONLY|O_APPEND, 0);
    691 				if (f->f_file < 0) {
    692 					f->f_type = F_UNUSED;
    693 					logerror(f->f_un.f_fname);
    694 				} else
    695 					goto again;
    696 			} else {
    697 				f->f_type = F_UNUSED;
    698 				errno = e;
    699 				logerror(f->f_un.f_fname);
    700 			}
    701 		} else if (flags & SYNC_FILE)
    702 			(void)fsync(f->f_file);
    703 		break;
    704 
    705 	case F_USERS:
    706 	case F_WALL:
    707 		dprintf("\n");
    708 		v->iov_base = "\r\n";
    709 		v->iov_len = 2;
    710 		wallmsg(f, iov);
    711 		break;
    712 	}
    713 	f->f_prevcount = 0;
    714 }
    715 
    716 /*
    717  *  WALLMSG -- Write a message to the world at large
    718  *
    719  *	Write the specified message to either the entire
    720  *	world, or a list of approved users.
    721  */
    722 void
    723 wallmsg(f, iov)
    724 	struct filed *f;
    725 	struct iovec *iov;
    726 {
    727 	static int reenter;			/* avoid calling ourselves */
    728 	FILE *uf;
    729 	struct utmp ut;
    730 	int i;
    731 	char *p;
    732 	char line[sizeof(ut.ut_line) + 1];
    733 
    734 	if (reenter++)
    735 		return;
    736 	if ((uf = fopen(_PATH_UTMP, "r")) == NULL) {
    737 		logerror(_PATH_UTMP);
    738 		reenter = 0;
    739 		return;
    740 	}
    741 	/* NOSTRICT */
    742 	while (fread((char *)&ut, sizeof(ut), 1, uf) == 1) {
    743 		if (ut.ut_name[0] == '\0')
    744 			continue;
    745 		strncpy(line, ut.ut_line, sizeof(ut.ut_line));
    746 		line[sizeof(ut.ut_line)] = '\0';
    747 		if (f->f_type == F_WALL) {
    748 			if ((p = ttymsg(iov, 6, line, TTYMSGTIME)) != NULL) {
    749 				errno = 0;	/* already in msg */
    750 				logerror(p);
    751 			}
    752 			continue;
    753 		}
    754 		/* should we send the message to this user? */
    755 		for (i = 0; i < MAXUNAMES; i++) {
    756 			if (!f->f_un.f_uname[i][0])
    757 				break;
    758 			if (!strncmp(f->f_un.f_uname[i], ut.ut_name,
    759 			    UT_NAMESIZE)) {
    760 				if ((p = ttymsg(iov, 6, line, TTYMSGTIME))
    761 								!= NULL) {
    762 					errno = 0;	/* already in msg */
    763 					logerror(p);
    764 				}
    765 				break;
    766 			}
    767 		}
    768 	}
    769 	(void)fclose(uf);
    770 	reenter = 0;
    771 }
    772 
    773 void
    774 reapchild(signo)
    775 	int signo;
    776 {
    777 	union wait status;
    778 
    779 	while (wait3((int *)&status, WNOHANG, (struct rusage *)NULL) > 0)
    780 		;
    781 }
    782 
    783 /*
    784  * Return a printable representation of a host address.
    785  */
    786 char *
    787 cvthname(f)
    788 	struct sockaddr_in *f;
    789 {
    790 	struct hostent *hp;
    791 	char *p;
    792 
    793 	dprintf("cvthname(%s)\n", inet_ntoa(f->sin_addr));
    794 
    795 	if (f->sin_family != AF_INET) {
    796 		dprintf("Malformed from address\n");
    797 		return ("???");
    798 	}
    799 	hp = gethostbyaddr((char *)&f->sin_addr,
    800 	    sizeof(struct in_addr), f->sin_family);
    801 	if (hp == 0) {
    802 		dprintf("Host name for your address (%s) unknown\n",
    803 			inet_ntoa(f->sin_addr));
    804 		return (inet_ntoa(f->sin_addr));
    805 	}
    806 	if ((p = strchr(hp->h_name, '.')) && strcmp(p + 1, LocalDomain) == 0)
    807 		*p = '\0';
    808 	return (hp->h_name);
    809 }
    810 
    811 void
    812 domark(signo)
    813 	int signo;
    814 {
    815 	struct filed *f;
    816 
    817 	now = time((time_t *)NULL);
    818 	MarkSeq += TIMERINTVL;
    819 	if (MarkSeq >= MarkInterval) {
    820 		logmsg(LOG_INFO, "-- MARK --", LocalHostName, ADDDATE|MARK);
    821 		MarkSeq = 0;
    822 	}
    823 
    824 	for (f = Files; f; f = f->f_next) {
    825 		if (f->f_prevcount && now >= REPEATTIME(f)) {
    826 			dprintf("flush %s: repeated %d times, %d sec.\n",
    827 			    TypeNames[f->f_type], f->f_prevcount,
    828 			    repeatinterval[f->f_repeatcount]);
    829 			fprintlog(f, 0, (char *)NULL);
    830 			BACKOFF(f);
    831 		}
    832 	}
    833 	(void)alarm(TIMERINTVL);
    834 }
    835 
    836 /*
    837  * Print syslogd errors some place.
    838  */
    839 void
    840 logerror(type)
    841 	char *type;
    842 {
    843 	char buf[100];
    844 
    845 	if (errno)
    846 		(void)snprintf(buf,
    847 		    sizeof(buf), "syslogd: %s: %s", type, strerror(errno));
    848 	else
    849 		(void)snprintf(buf, sizeof(buf), "syslogd: %s", type);
    850 	errno = 0;
    851 	dprintf("%s\n", buf);
    852 	logmsg(LOG_SYSLOG|LOG_ERR, buf, LocalHostName, ADDDATE);
    853 }
    854 
    855 void
    856 die(signo)
    857 	int signo;
    858 {
    859 	struct filed *f;
    860 	char buf[100];
    861 
    862 	for (f = Files; f != NULL; f = f->f_next) {
    863 		/* flush any pending output */
    864 		if (f->f_prevcount)
    865 			fprintlog(f, 0, (char *)NULL);
    866 	}
    867 	if (signo) {
    868 		dprintf("syslogd: exiting on signal %d\n", signo);
    869 		(void)sprintf(buf, "exiting on signal %d", signo);
    870 		errno = 0;
    871 		logerror(buf);
    872 	}
    873 	(void)unlink(LogName);
    874 	exit(0);
    875 }
    876 
    877 /*
    878  *  INIT -- Initialize syslogd from configuration table
    879  */
    880 void
    881 init(signo)
    882 	int signo;
    883 {
    884 	int i;
    885 	FILE *cf;
    886 	struct filed *f, *next, **nextp;
    887 	char *p;
    888 	char cline[LINE_MAX];
    889 
    890 	dprintf("init\n");
    891 
    892 	/*
    893 	 *  Close all open log files.
    894 	 */
    895 	Initialized = 0;
    896 	for (f = Files; f != NULL; f = next) {
    897 		/* flush any pending output */
    898 		if (f->f_prevcount)
    899 			fprintlog(f, 0, (char *)NULL);
    900 
    901 		switch (f->f_type) {
    902 		case F_FILE:
    903 		case F_TTY:
    904 		case F_CONSOLE:
    905 		case F_FORW:
    906 			(void)close(f->f_file);
    907 			break;
    908 		}
    909 		next = f->f_next;
    910 		free((char *)f);
    911 	}
    912 	Files = NULL;
    913 	nextp = &Files;
    914 
    915 	/* open the configuration file */
    916 	if ((cf = fopen(ConfFile, "r")) == NULL) {
    917 		dprintf("cannot open %s\n", ConfFile);
    918 		*nextp = (struct filed *)calloc(1, sizeof(*f));
    919 		cfline("*.ERR\t/dev/console", *nextp);
    920 		(*nextp)->f_next = (struct filed *)calloc(1, sizeof(*f));
    921 		cfline("*.PANIC\t*", (*nextp)->f_next);
    922 		Initialized = 1;
    923 		return;
    924 	}
    925 
    926 	/*
    927 	 *  Foreach line in the conf table, open that file.
    928 	 */
    929 	f = NULL;
    930 	while (fgets(cline, sizeof(cline), cf) != NULL) {
    931 		/*
    932 		 * check for end-of-section, comments, strip off trailing
    933 		 * spaces and newline character.
    934 		 */
    935 		for (p = cline; isspace(*p); ++p)
    936 			continue;
    937 		if (*p == '\0' || *p == '#')
    938 			continue;
    939 		for (p = strchr(cline, '\0'); isspace(*--p);)
    940 			continue;
    941 		*++p = '\0';
    942 		f = (struct filed *)calloc(1, sizeof(*f));
    943 		*nextp = f;
    944 		nextp = &f->f_next;
    945 		cfline(cline, f);
    946 	}
    947 
    948 	/* close the configuration file */
    949 	(void)fclose(cf);
    950 
    951 	Initialized = 1;
    952 
    953 	if (Debug) {
    954 		for (f = Files; f; f = f->f_next) {
    955 			for (i = 0; i <= LOG_NFACILITIES; i++)
    956 				if (f->f_pmask[i] == INTERNAL_NOPRI)
    957 					printf("X ");
    958 				else
    959 					printf("%d ", f->f_pmask[i]);
    960 			printf("%s: ", TypeNames[f->f_type]);
    961 			switch (f->f_type) {
    962 			case F_FILE:
    963 			case F_TTY:
    964 			case F_CONSOLE:
    965 				printf("%s", f->f_un.f_fname);
    966 				break;
    967 
    968 			case F_FORW:
    969 				printf("%s", f->f_un.f_forw.f_hname);
    970 				break;
    971 
    972 			case F_USERS:
    973 				for (i = 0; i < MAXUNAMES && *f->f_un.f_uname[i]; i++)
    974 					printf("%s, ", f->f_un.f_uname[i]);
    975 				break;
    976 			}
    977 			printf("\n");
    978 		}
    979 	}
    980 
    981 	logmsg(LOG_SYSLOG|LOG_INFO, "syslogd: restart", LocalHostName, ADDDATE);
    982 	dprintf("syslogd: restarted\n");
    983 }
    984 
    985 /*
    986  * Crack a configuration file line
    987  */
    988 void
    989 cfline(line, f)
    990 	char *line;
    991 	struct filed *f;
    992 {
    993 	struct hostent *hp;
    994 	int i, pri;
    995 	char *bp, *p, *q;
    996 	char buf[MAXLINE], ebuf[100];
    997 
    998 	dprintf("cfline(%s)\n", line);
    999 
   1000 	errno = 0;	/* keep strerror() stuff out of logerror messages */
   1001 
   1002 	/* clear out file entry */
   1003 	memset(f, 0, sizeof(*f));
   1004 	for (i = 0; i <= LOG_NFACILITIES; i++)
   1005 		f->f_pmask[i] = INTERNAL_NOPRI;
   1006 
   1007 	/* scan through the list of selectors */
   1008 	for (p = line; *p && *p != '\t';) {
   1009 
   1010 		/* find the end of this facility name list */
   1011 		for (q = p; *q && *q != '\t' && *q++ != '.'; )
   1012 			continue;
   1013 
   1014 		/* collect priority name */
   1015 		for (bp = buf; *q && !strchr("\t,;", *q); )
   1016 			*bp++ = *q++;
   1017 		*bp = '\0';
   1018 
   1019 		/* skip cruft */
   1020 		while (strchr(", ;", *q))
   1021 			q++;
   1022 
   1023 		/* decode priority name */
   1024 		if (*buf == '*')
   1025 			pri = LOG_PRIMASK + 1;
   1026 		else {
   1027 			pri = decode(buf, prioritynames);
   1028 			if (pri < 0) {
   1029 				(void)sprintf(ebuf,
   1030 				    "unknown priority name \"%s\"", buf);
   1031 				logerror(ebuf);
   1032 				return;
   1033 			}
   1034 		}
   1035 
   1036 		/* scan facilities */
   1037 		while (*p && !strchr("\t.;", *p)) {
   1038 			for (bp = buf; *p && !strchr("\t,;.", *p); )
   1039 				*bp++ = *p++;
   1040 			*bp = '\0';
   1041 			if (*buf == '*')
   1042 				for (i = 0; i < LOG_NFACILITIES; i++)
   1043 					f->f_pmask[i] = pri;
   1044 			else {
   1045 				i = decode(buf, facilitynames);
   1046 				if (i < 0) {
   1047 					(void)sprintf(ebuf,
   1048 					    "unknown facility name \"%s\"",
   1049 					    buf);
   1050 					logerror(ebuf);
   1051 					return;
   1052 				}
   1053 				f->f_pmask[i >> 3] = pri;
   1054 			}
   1055 			while (*p == ',' || *p == ' ')
   1056 				p++;
   1057 		}
   1058 
   1059 		p = q;
   1060 	}
   1061 
   1062 	/* skip to action part */
   1063 	while (*p == '\t')
   1064 		p++;
   1065 
   1066 	switch (*p)
   1067 	{
   1068 	case '@':
   1069 		if (!InetInuse)
   1070 			break;
   1071 		(void)strcpy(f->f_un.f_forw.f_hname, ++p);
   1072 		hp = gethostbyname(p);
   1073 		if (hp == NULL) {
   1074 			extern int h_errno;
   1075 
   1076 			logerror((char *)hstrerror(h_errno));
   1077 			break;
   1078 		}
   1079 		memset(&f->f_un.f_forw.f_addr, 0,
   1080 			 sizeof(f->f_un.f_forw.f_addr));
   1081 		f->f_un.f_forw.f_addr.sin_family = AF_INET;
   1082 		f->f_un.f_forw.f_addr.sin_port = LogPort;
   1083 		memmove(&f->f_un.f_forw.f_addr.sin_addr, hp->h_addr, hp->h_length);
   1084 		f->f_type = F_FORW;
   1085 		break;
   1086 
   1087 	case '/':
   1088 		(void)strcpy(f->f_un.f_fname, p);
   1089 		if ((f->f_file = open(p, O_WRONLY|O_APPEND, 0)) < 0) {
   1090 			f->f_file = F_UNUSED;
   1091 			logerror(p);
   1092 			break;
   1093 		}
   1094 		if (isatty(f->f_file))
   1095 			f->f_type = F_TTY;
   1096 		else
   1097 			f->f_type = F_FILE;
   1098 		if (strcmp(p, ctty) == 0)
   1099 			f->f_type = F_CONSOLE;
   1100 		break;
   1101 
   1102 	case '*':
   1103 		f->f_type = F_WALL;
   1104 		break;
   1105 
   1106 	default:
   1107 		for (i = 0; i < MAXUNAMES && *p; i++) {
   1108 			for (q = p; *q && *q != ','; )
   1109 				q++;
   1110 			(void)strncpy(f->f_un.f_uname[i], p, UT_NAMESIZE);
   1111 			if ((q - p) > UT_NAMESIZE)
   1112 				f->f_un.f_uname[i][UT_NAMESIZE] = '\0';
   1113 			else
   1114 				f->f_un.f_uname[i][q - p] = '\0';
   1115 			while (*q == ',' || *q == ' ')
   1116 				q++;
   1117 			p = q;
   1118 		}
   1119 		f->f_type = F_USERS;
   1120 		break;
   1121 	}
   1122 }
   1123 
   1124 
   1125 /*
   1126  *  Decode a symbolic name to a numeric value
   1127  */
   1128 int
   1129 decode(name, codetab)
   1130 	const char *name;
   1131 	CODE *codetab;
   1132 {
   1133 	CODE *c;
   1134 	char *p, buf[40];
   1135 
   1136 	if (isdigit(*name))
   1137 		return (atoi(name));
   1138 
   1139 	for (p = buf; *name && p < &buf[sizeof(buf) - 1]; p++, name++) {
   1140 		if (isupper(*name))
   1141 			*p = tolower(*name);
   1142 		else
   1143 			*p = *name;
   1144 	}
   1145 	*p = '\0';
   1146 	for (c = codetab; c->c_name; c++)
   1147 		if (!strcmp(buf, c->c_name))
   1148 			return (c->c_val);
   1149 
   1150 	return (-1);
   1151 }
   1152