xref: /freebsd-12.1/usr.sbin/syslogd/syslogd.c (revision 75b3fc34)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1983, 1988, 1993, 1994
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 /*-
32  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
33  *
34  * Copyright (c) 2018 Prodrive Technologies, https://prodrive-technologies.com/
35  * Author: Ed Schouten <[email protected]>
36  *
37  * Redistribution and use in source and binary forms, with or without
38  * modification, are permitted provided that the following conditions
39  * are met:
40  * 1. Redistributions of source code must retain the above copyright
41  *    notice, this list of conditions and the following disclaimer.
42  * 2. Redistributions in binary form must reproduce the above copyright
43  *    notice, this list of conditions and the following disclaimer in the
44  *    documentation and/or other materials provided with the distribution.
45  *
46  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
47  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
48  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
49  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
50  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
51  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
52  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
53  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
54  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
55  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
56  * SUCH DAMAGE.
57  */
58 
59 #ifndef lint
60 static const char copyright[] =
61 "@(#) Copyright (c) 1983, 1988, 1993, 1994\n\
62 	The Regents of the University of California.  All rights reserved.\n";
63 #endif /* not lint */
64 
65 #ifndef lint
66 #if 0
67 static char sccsid[] = "@(#)syslogd.c	8.3 (Berkeley) 4/4/94";
68 #endif
69 #endif /* not lint */
70 
71 #include <sys/cdefs.h>
72 __FBSDID("$FreeBSD$");
73 
74 /*
75  *  syslogd -- log system messages
76  *
77  * This program implements a system log. It takes a series of lines.
78  * Each line may have a priority, signified as "<n>" as
79  * the first characters of the line.  If this is
80  * not present, a default priority is used.
81  *
82  * To kill syslogd, send a signal 15 (terminate).  A signal 1 (hup) will
83  * cause it to reread its configuration file.
84  *
85  * Defined Constants:
86  *
87  * MAXLINE -- the maximum line length that can be handled.
88  * DEFUPRI -- the default priority for user messages
89  * DEFSPRI -- the default priority for kernel messages
90  *
91  * Author: Eric Allman
92  * extensive changes by Ralph Campbell
93  * more extensive changes by Eric Allman (again)
94  * Extension to log by program name as well as facility and priority
95  *   by Peter da Silva.
96  * -u and -v by Harlan Stenn.
97  * Priority comparison code by Harlan Stenn.
98  */
99 
100 /* Maximum number of characters in time of last occurrence */
101 #define	MAXLINE		2048		/* maximum line length */
102 #define	MAXSVLINE	MAXLINE		/* maximum saved line length */
103 #define	DEFUPRI		(LOG_USER|LOG_NOTICE)
104 #define	DEFSPRI		(LOG_KERN|LOG_CRIT)
105 #define	TIMERINTVL	30		/* interval for checking flush, mark */
106 #define	TTYMSGTIME	1		/* timeout passed to ttymsg */
107 #define	RCVBUF_MINSIZE	(80 * 1024)	/* minimum size of dgram rcv buffer */
108 
109 #include <sys/param.h>
110 #include <sys/ioctl.h>
111 #include <sys/mman.h>
112 #include <sys/queue.h>
113 #include <sys/resource.h>
114 #include <sys/socket.h>
115 #include <sys/stat.h>
116 #include <sys/syslimits.h>
117 #include <sys/time.h>
118 #include <sys/uio.h>
119 #include <sys/un.h>
120 #include <sys/wait.h>
121 
122 #if defined(INET) || defined(INET6)
123 #include <netinet/in.h>
124 #include <arpa/inet.h>
125 #endif
126 
127 #include <assert.h>
128 #include <ctype.h>
129 #include <dirent.h>
130 #include <err.h>
131 #include <errno.h>
132 #include <fcntl.h>
133 #include <fnmatch.h>
134 #include <libutil.h>
135 #include <limits.h>
136 #include <netdb.h>
137 #include <paths.h>
138 #include <signal.h>
139 #include <stdbool.h>
140 #include <stdio.h>
141 #include <stdlib.h>
142 #include <string.h>
143 #include <sysexits.h>
144 #include <unistd.h>
145 #include <utmpx.h>
146 
147 #include "pathnames.h"
148 #include "ttymsg.h"
149 
150 #define SYSLOG_NAMES
151 #include <sys/syslog.h>
152 
153 static const char *ConfFile = _PATH_LOGCONF;
154 static const char *PidFile = _PATH_LOGPID;
155 static const char ctty[] = _PATH_CONSOLE;
156 static const char include_str[] = "include";
157 static const char include_ext[] = ".conf";
158 
159 #define	dprintf		if (Debug) printf
160 
161 #define	MAXUNAMES	20	/* maximum number of user names */
162 
163 #define	sstosa(ss)	((struct sockaddr *)(ss))
164 #ifdef INET
165 #define	sstosin(ss)	((struct sockaddr_in *)(void *)(ss))
166 #define	satosin(sa)	((struct sockaddr_in *)(void *)(sa))
167 #endif
168 #ifdef INET6
169 #define	sstosin6(ss)	((struct sockaddr_in6 *)(void *)(ss))
170 #define	satosin6(sa)	((struct sockaddr_in6 *)(void *)(sa))
171 #define	s6_addr32	__u6_addr.__u6_addr32
172 #define	IN6_ARE_MASKED_ADDR_EQUAL(d, a, m)	(	\
173 	(((d)->s6_addr32[0] ^ (a)->s6_addr32[0]) & (m)->s6_addr32[0]) == 0 && \
174 	(((d)->s6_addr32[1] ^ (a)->s6_addr32[1]) & (m)->s6_addr32[1]) == 0 && \
175 	(((d)->s6_addr32[2] ^ (a)->s6_addr32[2]) & (m)->s6_addr32[2]) == 0 && \
176 	(((d)->s6_addr32[3] ^ (a)->s6_addr32[3]) & (m)->s6_addr32[3]) == 0 )
177 #endif
178 /*
179  * List of peers and sockets for binding.
180  */
181 struct peer {
182 	const char	*pe_name;
183 	const char	*pe_serv;
184 	mode_t		pe_mode;
185 	STAILQ_ENTRY(peer)	next;
186 };
187 static STAILQ_HEAD(, peer) pqueue = STAILQ_HEAD_INITIALIZER(pqueue);
188 
189 struct socklist {
190 	struct sockaddr_storage	sl_ss;
191 	int			sl_socket;
192 	struct peer		*sl_peer;
193 	int			(*sl_recv)(struct socklist *);
194 	STAILQ_ENTRY(socklist)	next;
195 };
196 static STAILQ_HEAD(, socklist) shead = STAILQ_HEAD_INITIALIZER(shead);
197 
198 /*
199  * Flags to logmsg().
200  */
201 
202 #define	IGN_CONS	0x001	/* don't print on console */
203 #define	SYNC_FILE	0x002	/* do fsync on file after printing */
204 #define	MARK		0x008	/* this message is a mark */
205 
206 /* Timestamps of log entries. */
207 struct logtime {
208 	struct tm	tm;
209 	suseconds_t	usec;
210 };
211 
212 /* Traditional syslog timestamp format. */
213 #define	RFC3164_DATELEN	15
214 #define	RFC3164_DATEFMT	"%b %e %H:%M:%S"
215 
216 /*
217  * This structure represents the files that will have log
218  * copies printed.
219  * We require f_file to be valid if f_type is F_FILE, F_CONSOLE, F_TTY
220  * or if f_type is F_PIPE and f_pid > 0.
221  */
222 
223 struct filed {
224 	STAILQ_ENTRY(filed)	next;	/* next in linked list */
225 	short	f_type;			/* entry type, see below */
226 	short	f_file;			/* file descriptor */
227 	time_t	f_time;			/* time this was last written */
228 	char	*f_host;		/* host from which to recd. */
229 	u_char	f_pmask[LOG_NFACILITIES+1];	/* priority mask */
230 	u_char	f_pcmp[LOG_NFACILITIES+1];	/* compare priority */
231 #define PRI_LT	0x1
232 #define PRI_EQ	0x2
233 #define PRI_GT	0x4
234 	char	*f_program;		/* program this applies to */
235 	union {
236 		char	f_uname[MAXUNAMES][MAXLOGNAME];
237 		struct {
238 			char	f_hname[MAXHOSTNAMELEN];
239 			struct addrinfo *f_addr;
240 
241 		} f_forw;		/* forwarding address */
242 		char	f_fname[MAXPATHLEN];
243 		struct {
244 			char	f_pname[MAXPATHLEN];
245 			pid_t	f_pid;
246 		} f_pipe;
247 	} f_un;
248 #define	fu_uname	f_un.f_uname
249 #define	fu_forw_hname	f_un.f_forw.f_hname
250 #define	fu_forw_addr	f_un.f_forw.f_addr
251 #define	fu_fname	f_un.f_fname
252 #define	fu_pipe_pname	f_un.f_pipe.f_pname
253 #define	fu_pipe_pid	f_un.f_pipe.f_pid
254 	char	f_prevline[MAXSVLINE];		/* last message logged */
255 	struct logtime f_lasttime;		/* time of last occurrence */
256 	int	f_prevpri;			/* pri of f_prevline */
257 	size_t	f_prevlen;			/* length of f_prevline */
258 	int	f_prevcount;			/* repetition cnt of prevline */
259 	u_int	f_repeatcount;			/* number of "repeated" msgs */
260 	int	f_flags;			/* file-specific flags */
261 #define	FFLAG_SYNC 0x01
262 #define	FFLAG_NEEDSYNC	0x02
263 };
264 
265 /*
266  * Queue of about-to-be dead processes we should watch out for.
267  */
268 struct deadq_entry {
269 	pid_t				dq_pid;
270 	int				dq_timeout;
271 	TAILQ_ENTRY(deadq_entry)	dq_entries;
272 };
273 static TAILQ_HEAD(, deadq_entry) deadq_head =
274     TAILQ_HEAD_INITIALIZER(deadq_head);
275 
276 /*
277  * The timeout to apply to processes waiting on the dead queue.  Unit
278  * of measure is `mark intervals', i.e. 20 minutes by default.
279  * Processes on the dead queue will be terminated after that time.
280  */
281 
282 #define	 DQ_TIMO_INIT	2
283 
284 /*
285  * Struct to hold records of network addresses that are allowed to log
286  * to us.
287  */
288 struct allowedpeer {
289 	int isnumeric;
290 	u_short port;
291 	union {
292 		struct {
293 			struct sockaddr_storage addr;
294 			struct sockaddr_storage mask;
295 		} numeric;
296 		char *name;
297 	} u;
298 #define a_addr u.numeric.addr
299 #define a_mask u.numeric.mask
300 #define a_name u.name
301 	STAILQ_ENTRY(allowedpeer)	next;
302 };
303 static STAILQ_HEAD(, allowedpeer) aphead = STAILQ_HEAD_INITIALIZER(aphead);
304 
305 
306 /*
307  * Intervals at which we flush out "message repeated" messages,
308  * in seconds after previous message is logged.  After each flush,
309  * we move to the next interval until we reach the largest.
310  */
311 static int repeatinterval[] = { 30, 120, 600 };	/* # of secs before flush */
312 #define	MAXREPEAT	(nitems(repeatinterval) - 1)
313 #define	REPEATTIME(f)	((f)->f_time + repeatinterval[(f)->f_repeatcount])
314 #define	BACKOFF(f)	do {						\
315 				if (++(f)->f_repeatcount > MAXREPEAT)	\
316 					(f)->f_repeatcount = MAXREPEAT;	\
317 			} while (0)
318 
319 /* values for f_type */
320 #define F_UNUSED	0		/* unused entry */
321 #define F_FILE		1		/* regular file */
322 #define F_TTY		2		/* terminal */
323 #define F_CONSOLE	3		/* console terminal */
324 #define F_FORW		4		/* remote machine */
325 #define F_USERS		5		/* list of users */
326 #define F_WALL		6		/* everyone logged on */
327 #define F_PIPE		7		/* pipe to program */
328 
329 static const char *TypeNames[] = {
330 	"UNUSED",	"FILE",		"TTY",		"CONSOLE",
331 	"FORW",		"USERS",	"WALL",		"PIPE"
332 };
333 
334 static STAILQ_HEAD(, filed) fhead =
335     STAILQ_HEAD_INITIALIZER(fhead);	/* Log files that we write to */
336 static struct filed consfile;	/* Console */
337 
338 static int	Debug;		/* debug flag */
339 static int	Foreground = 0;	/* Run in foreground, instead of daemonizing */
340 static int	resolve = 1;	/* resolve hostname */
341 static char	LocalHostName[MAXHOSTNAMELEN];	/* our hostname */
342 static const char *LocalDomain;	/* our local domain name */
343 static int	Initialized;	/* set when we have initialized ourselves */
344 static int	MarkInterval = 20 * 60;	/* interval between marks in seconds */
345 static int	MarkSeq;	/* mark sequence number */
346 static int	NoBind;		/* don't bind() as suggested by RFC 3164 */
347 static int	SecureMode;	/* when true, receive only unix domain socks */
348 #ifdef INET6
349 static int	family = PF_UNSPEC; /* protocol family (IPv4, IPv6 or both) */
350 #else
351 static int	family = PF_INET; /* protocol family (IPv4 only) */
352 #endif
353 static int	mask_C1 = 1;	/* mask characters from 0x80 - 0x9F */
354 static int	send_to_all;	/* send message to all IPv4/IPv6 addresses */
355 static int	use_bootfile;	/* log entire bootfile for every kern msg */
356 static int	no_compress;	/* don't compress messages (1=pipes, 2=all) */
357 static int	logflags = O_WRONLY|O_APPEND; /* flags used to open log files */
358 
359 static char	bootfile[MAXLINE+1]; /* booted kernel file */
360 
361 static int	RemoteAddDate;	/* Always set the date on remote messages */
362 static int	RemoteHostname;	/* Log remote hostname from the message */
363 
364 static int	UniquePriority;	/* Only log specified priority? */
365 static int	LogFacPri;	/* Put facility and priority in log message: */
366 				/* 0=no, 1=numeric, 2=names */
367 static int	KeepKernFac;	/* Keep remotely logged kernel facility */
368 static int	needdofsync = 0; /* Are any file(s) waiting to be fsynced? */
369 static struct pidfh *pfh;
370 static int	sigpipe[2];	/* Pipe to catch a signal during select(). */
371 static bool	RFC3164OutputFormat = true; /* Use legacy format by default. */
372 
373 static volatile sig_atomic_t MarkSet, WantDie, WantInitialize, WantReapchild;
374 
375 struct iovlist;
376 
377 static int	allowaddr(char *);
378 static int	addfile(struct filed *);
379 static int	addpeer(struct peer *);
380 static int	addsock(struct sockaddr *, socklen_t, struct socklist *);
381 static struct filed *cfline(const char *, const char *, const char *);
382 static const char *cvthname(struct sockaddr *);
383 static void	deadq_enter(pid_t, const char *);
384 static int	deadq_remove(struct deadq_entry *);
385 static int	deadq_removebypid(pid_t);
386 static int	decode(const char *, const CODE *);
387 static void	die(int) __dead2;
388 static void	dodie(int);
389 static void	dofsync(void);
390 static void	domark(int);
391 static void	fprintlog_first(struct filed *, const char *, const char *,
392     const char *, const char *, const char *, const char *, int);
393 static void	fprintlog_write(struct filed *, struct iovlist *, int);
394 static void	fprintlog_successive(struct filed *, int);
395 static void	init(int);
396 static void	logerror(const char *);
397 static void	logmsg(int, const struct logtime *, const char *, const char *,
398     const char *, const char *, const char *, const char *, int);
399 static void	log_deadchild(pid_t, int, const char *);
400 static void	markit(void);
401 static int	socksetup(struct peer *);
402 static int	socklist_recv_file(struct socklist *);
403 static int	socklist_recv_sock(struct socklist *);
404 static int	socklist_recv_signal(struct socklist *);
405 static void	sighandler(int);
406 static int	skip_message(const char *, const char *, int);
407 static void	parsemsg(const char *, char *);
408 static void	printsys(char *);
409 static int	p_open(const char *, pid_t *);
410 static void	reapchild(int);
411 static const char *ttymsg_check(struct iovec *, int, char *, int);
412 static void	usage(void);
413 static int	validate(struct sockaddr *, const char *);
414 static void	unmapped(struct sockaddr *);
415 static void	wallmsg(struct filed *, struct iovec *, const int iovlen);
416 static int	waitdaemon(int);
417 static void	timedout(int);
418 static void	increase_rcvbuf(int);
419 
420 static void
close_filed(struct filed * f)421 close_filed(struct filed *f)
422 {
423 
424 	if (f == NULL || f->f_file == -1)
425 		return;
426 
427 	switch (f->f_type) {
428 	case F_FORW:
429 		if (f->f_un.f_forw.f_addr) {
430 			freeaddrinfo(f->f_un.f_forw.f_addr);
431 			f->f_un.f_forw.f_addr = NULL;
432 		}
433 		/* FALLTHROUGH */
434 
435 	case F_FILE:
436 	case F_TTY:
437 	case F_CONSOLE:
438 		f->f_type = F_UNUSED;
439 		break;
440 	case F_PIPE:
441 		f->fu_pipe_pid = 0;
442 		break;
443 	}
444 	(void)close(f->f_file);
445 	f->f_file = -1;
446 }
447 
448 static int
addfile(struct filed * f0)449 addfile(struct filed *f0)
450 {
451 	struct filed *f;
452 
453 	f = calloc(1, sizeof(*f));
454 	if (f == NULL)
455 		err(1, "malloc failed");
456 	*f = *f0;
457 	STAILQ_INSERT_TAIL(&fhead, f, next);
458 
459 	return (0);
460 }
461 
462 static int
addpeer(struct peer * pe0)463 addpeer(struct peer *pe0)
464 {
465 	struct peer *pe;
466 
467 	pe = calloc(1, sizeof(*pe));
468 	if (pe == NULL)
469 		err(1, "malloc failed");
470 	*pe = *pe0;
471 	STAILQ_INSERT_TAIL(&pqueue, pe, next);
472 
473 	return (0);
474 }
475 
476 static int
addsock(struct sockaddr * sa,socklen_t sa_len,struct socklist * sl0)477 addsock(struct sockaddr *sa, socklen_t sa_len, struct socklist *sl0)
478 {
479 	struct socklist *sl;
480 
481 	sl = calloc(1, sizeof(*sl));
482 	if (sl == NULL)
483 		err(1, "malloc failed");
484 	*sl = *sl0;
485 	if (sa != NULL && sa_len > 0)
486 		memcpy(&sl->sl_ss, sa, sa_len);
487 	STAILQ_INSERT_TAIL(&shead, sl, next);
488 
489 	return (0);
490 }
491 
492 int
main(int argc,char * argv[])493 main(int argc, char *argv[])
494 {
495 	int ch, i, s, fdsrmax = 0, bflag = 0, pflag = 0, Sflag = 0;
496 	fd_set *fdsr = NULL;
497 	struct timeval tv, *tvp;
498 	struct peer *pe;
499 	struct socklist *sl;
500 	pid_t ppid = 1, spid;
501 	char *p;
502 
503 	if (madvise(NULL, 0, MADV_PROTECT) != 0)
504 		dprintf("madvise() failed: %s\n", strerror(errno));
505 
506 	while ((ch = getopt(argc, argv, "468Aa:b:cCdf:FHkl:m:nNoO:p:P:sS:Tuv"))
507 	    != -1)
508 		switch (ch) {
509 #ifdef INET
510 		case '4':
511 			family = PF_INET;
512 			break;
513 #endif
514 #ifdef INET6
515 		case '6':
516 			family = PF_INET6;
517 			break;
518 #endif
519 		case '8':
520 			mask_C1 = 0;
521 			break;
522 		case 'A':
523 			send_to_all++;
524 			break;
525 		case 'a':		/* allow specific network addresses only */
526 			if (allowaddr(optarg) == -1)
527 				usage();
528 			break;
529 		case 'b':
530 			bflag = 1;
531 			p = strchr(optarg, ']');
532 			if (p != NULL)
533 				p = strchr(p + 1, ':');
534 			else {
535 				p = strchr(optarg, ':');
536 				if (p != NULL && strchr(p + 1, ':') != NULL)
537 					p = NULL; /* backward compatibility */
538 			}
539 			if (p == NULL) {
540 				/* A hostname or filename only. */
541 				addpeer(&(struct peer){
542 					.pe_name = optarg,
543 					.pe_serv = "syslog"
544 				});
545 			} else {
546 				/* The case of "name:service". */
547 				*p++ = '\0';
548 				addpeer(&(struct peer){
549 					.pe_serv = p,
550 					.pe_name = (strlen(optarg) == 0) ?
551 					    NULL : optarg,
552 				});
553 			}
554 			break;
555 		case 'c':
556 			no_compress++;
557 			break;
558 		case 'C':
559 			logflags |= O_CREAT;
560 			break;
561 		case 'd':		/* debug */
562 			Debug++;
563 			break;
564 		case 'f':		/* configuration file */
565 			ConfFile = optarg;
566 			break;
567 		case 'F':		/* run in foreground instead of daemon */
568 			Foreground++;
569 			break;
570 		case 'H':
571 			RemoteHostname = 1;
572 			break;
573 		case 'k':		/* keep remote kern fac */
574 			KeepKernFac = 1;
575 			break;
576 		case 'l':
577 		case 'p':
578 		case 'S':
579 		    {
580 			long	perml;
581 			mode_t	mode;
582 			char	*name, *ep;
583 
584 			if (ch == 'l')
585 				mode = DEFFILEMODE;
586 			else if (ch == 'p') {
587 				mode = DEFFILEMODE;
588 				pflag = 1;
589 			} else {
590 				mode = S_IRUSR | S_IWUSR;
591 				Sflag = 1;
592 			}
593 			if (optarg[0] == '/')
594 				name = optarg;
595 			else if ((name = strchr(optarg, ':')) != NULL) {
596 				*name++ = '\0';
597 				if (name[0] != '/')
598 					errx(1, "socket name must be absolute "
599 					    "path");
600 				if (isdigit(*optarg)) {
601 					perml = strtol(optarg, &ep, 8);
602 				    if (*ep || perml < 0 ||
603 					perml & ~(S_IRWXU|S_IRWXG|S_IRWXO))
604 					    errx(1, "invalid mode %s, exiting",
605 						optarg);
606 				    mode = (mode_t )perml;
607 				} else
608 					errx(1, "invalid mode %s, exiting",
609 					    optarg);
610 			} else
611 				errx(1, "invalid filename %s, exiting",
612 				    optarg);
613 			addpeer(&(struct peer){
614 				.pe_name = name,
615 				.pe_mode = mode
616 			});
617 			break;
618 		   }
619 		case 'm':		/* mark interval */
620 			MarkInterval = atoi(optarg) * 60;
621 			break;
622 		case 'N':
623 			NoBind = 1;
624 			SecureMode = 1;
625 			break;
626 		case 'n':
627 			resolve = 0;
628 			break;
629 		case 'O':
630 			if (strcmp(optarg, "bsd") == 0 ||
631 			    strcmp(optarg, "rfc3164") == 0)
632 				RFC3164OutputFormat = true;
633 			else if (strcmp(optarg, "syslog") == 0 ||
634 			    strcmp(optarg, "rfc5424") == 0)
635 				RFC3164OutputFormat = false;
636 			else
637 				usage();
638 			break;
639 		case 'o':
640 			use_bootfile = 1;
641 			break;
642 		case 'P':		/* path for alt. PID */
643 			PidFile = optarg;
644 			break;
645 		case 's':		/* no network mode */
646 			SecureMode++;
647 			break;
648 		case 'T':
649 			RemoteAddDate = 1;
650 			break;
651 		case 'u':		/* only log specified priority */
652 			UniquePriority++;
653 			break;
654 		case 'v':		/* log facility and priority */
655 		  	LogFacPri++;
656 			break;
657 		default:
658 			usage();
659 		}
660 	if ((argc -= optind) != 0)
661 		usage();
662 
663 	/* Pipe to catch a signal during select(). */
664 	s = pipe2(sigpipe, O_CLOEXEC);
665 	if (s < 0) {
666 		err(1, "cannot open a pipe for signals");
667 	} else {
668 		addsock(NULL, 0, &(struct socklist){
669 		    .sl_socket = sigpipe[0],
670 		    .sl_recv = socklist_recv_signal
671 		});
672 	}
673 
674 	/* Listen by default: /dev/klog. */
675 	s = open(_PATH_KLOG, O_RDONLY | O_NONBLOCK | O_CLOEXEC, 0);
676 	if (s < 0) {
677 		dprintf("can't open %s (%d)\n", _PATH_KLOG, errno);
678 	} else {
679 		addsock(NULL, 0, &(struct socklist){
680 			.sl_socket = s,
681 			.sl_recv = socklist_recv_file,
682 		});
683 	}
684 	/* Listen by default: *:514 if no -b flag. */
685 	if (bflag == 0)
686 		addpeer(&(struct peer){
687 			.pe_serv = "syslog"
688 		});
689 	/* Listen by default: /var/run/log if no -p flag. */
690 	if (pflag == 0)
691 		addpeer(&(struct peer){
692 			.pe_name = _PATH_LOG,
693 			.pe_mode = DEFFILEMODE,
694 		});
695 	/* Listen by default: /var/run/logpriv if no -S flag. */
696 	if (Sflag == 0)
697 		addpeer(&(struct peer){
698 			.pe_name = _PATH_LOG_PRIV,
699 			.pe_mode = S_IRUSR | S_IWUSR,
700 		});
701 	STAILQ_FOREACH(pe, &pqueue, next)
702 		socksetup(pe);
703 
704 	pfh = pidfile_open(PidFile, 0600, &spid);
705 	if (pfh == NULL) {
706 		if (errno == EEXIST)
707 			errx(1, "syslogd already running, pid: %d", spid);
708 		warn("cannot open pid file");
709 	}
710 
711 	if ((!Foreground) && (!Debug)) {
712 		ppid = waitdaemon(30);
713 		if (ppid < 0) {
714 			warn("could not become daemon");
715 			pidfile_remove(pfh);
716 			exit(1);
717 		}
718 	} else if (Debug)
719 		setlinebuf(stdout);
720 
721 	consfile.f_type = F_CONSOLE;
722 	(void)strlcpy(consfile.fu_fname, ctty + sizeof _PATH_DEV - 1,
723 	    sizeof(consfile.fu_fname));
724 	(void)strlcpy(bootfile, getbootfile(), sizeof(bootfile));
725 	(void)signal(SIGTERM, dodie);
726 	(void)signal(SIGINT, Debug ? dodie : SIG_IGN);
727 	(void)signal(SIGQUIT, Debug ? dodie : SIG_IGN);
728 	(void)signal(SIGHUP, sighandler);
729 	(void)signal(SIGCHLD, sighandler);
730 	(void)signal(SIGALRM, domark);
731 	(void)signal(SIGPIPE, SIG_IGN);	/* We'll catch EPIPE instead. */
732 	(void)alarm(TIMERINTVL);
733 
734 	/* tuck my process id away */
735 	pidfile_write(pfh);
736 
737 	dprintf("off & running....\n");
738 
739 	tvp = &tv;
740 	tv.tv_sec = tv.tv_usec = 0;
741 
742 	STAILQ_FOREACH(sl, &shead, next) {
743 		if (sl->sl_socket > fdsrmax)
744 			fdsrmax = sl->sl_socket;
745 	}
746 	fdsr = (fd_set *)calloc(howmany(fdsrmax+1, NFDBITS),
747 	    sizeof(*fdsr));
748 	if (fdsr == NULL)
749 		errx(1, "calloc fd_set");
750 
751 	for (;;) {
752 		if (Initialized == 0)
753 			init(0);
754 		else if (WantInitialize)
755 			init(WantInitialize);
756 		if (WantReapchild)
757 			reapchild(WantReapchild);
758 		if (MarkSet)
759 			markit();
760 		if (WantDie) {
761 			free(fdsr);
762 			die(WantDie);
763 		}
764 
765 		bzero(fdsr, howmany(fdsrmax+1, NFDBITS) *
766 		    sizeof(*fdsr));
767 
768 		STAILQ_FOREACH(sl, &shead, next) {
769 			if (sl->sl_socket != -1 && sl->sl_recv != NULL)
770 				FD_SET(sl->sl_socket, fdsr);
771 		}
772 		i = select(fdsrmax + 1, fdsr, NULL, NULL,
773 		    needdofsync ? &tv : tvp);
774 		switch (i) {
775 		case 0:
776 			dofsync();
777 			needdofsync = 0;
778 			if (tvp) {
779 				tvp = NULL;
780 				if (ppid != 1)
781 					kill(ppid, SIGALRM);
782 			}
783 			continue;
784 		case -1:
785 			if (errno != EINTR)
786 				logerror("select");
787 			continue;
788 		}
789 		STAILQ_FOREACH(sl, &shead, next) {
790 			if (FD_ISSET(sl->sl_socket, fdsr))
791 				(*sl->sl_recv)(sl);
792 		}
793 	}
794 	free(fdsr);
795 }
796 
797 static int
socklist_recv_signal(struct socklist * sl __unused)798 socklist_recv_signal(struct socklist *sl __unused)
799 {
800 	ssize_t len;
801 	int i, nsig, signo;
802 
803 	if (ioctl(sigpipe[0], FIONREAD, &i) != 0) {
804 		logerror("ioctl(FIONREAD)");
805 		err(1, "signal pipe read failed");
806 	}
807 	nsig = i / sizeof(signo);
808 	dprintf("# of received signals = %d\n", nsig);
809 	for (i = 0; i < nsig; i++) {
810 		len = read(sigpipe[0], &signo, sizeof(signo));
811 		if (len != sizeof(signo)) {
812 			logerror("signal pipe read failed");
813 			err(1, "signal pipe read failed");
814 		}
815 		dprintf("Received signal: %d from fd=%d\n", signo,
816 		    sigpipe[0]);
817 		switch (signo) {
818 		case SIGHUP:
819 			WantInitialize = 1;
820 			break;
821 		case SIGCHLD:
822 			WantReapchild = 1;
823 			break;
824 		}
825 	}
826 	return (0);
827 }
828 
829 static int
socklist_recv_sock(struct socklist * sl)830 socklist_recv_sock(struct socklist *sl)
831 {
832 	struct sockaddr_storage ss;
833 	struct sockaddr *sa = (struct sockaddr *)&ss;
834 	socklen_t sslen;
835 	const char *hname;
836 	char line[MAXLINE + 1];
837 	int len;
838 
839 	sslen = sizeof(ss);
840 	len = recvfrom(sl->sl_socket, line, sizeof(line) - 1, 0, sa, &sslen);
841 	dprintf("received sa_len = %d\n", sslen);
842 	if (len == 0)
843 		return (-1);
844 	if (len < 0) {
845 		if (errno != EINTR)
846 			logerror("recvfrom");
847 		return (-1);
848 	}
849 	/* Received valid data. */
850 	line[len] = '\0';
851 	if (sl->sl_ss.ss_family == AF_LOCAL)
852 		hname = LocalHostName;
853 	else {
854 		hname = cvthname(sa);
855 		unmapped(sa);
856 		if (validate(sa, hname) == 0) {
857 			dprintf("Message from %s was ignored.", hname);
858 			return (-1);
859 		}
860 	}
861 	parsemsg(hname, line);
862 
863 	return (0);
864 }
865 
866 static void
unmapped(struct sockaddr * sa)867 unmapped(struct sockaddr *sa)
868 {
869 #if defined(INET) && defined(INET6)
870 	struct sockaddr_in6 *sin6;
871 	struct sockaddr_in sin;
872 
873 	if (sa == NULL ||
874 	    sa->sa_family != AF_INET6 ||
875 	    sa->sa_len != sizeof(*sin6))
876 		return;
877 	sin6 = satosin6(sa);
878 	if (!IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr))
879 		return;
880 	sin = (struct sockaddr_in){
881 		.sin_family = AF_INET,
882 		.sin_len = sizeof(sin),
883 		.sin_port = sin6->sin6_port
884 	};
885 	memcpy(&sin.sin_addr, &sin6->sin6_addr.s6_addr[12],
886 	    sizeof(sin.sin_addr));
887 	memcpy(sa, &sin, sizeof(sin));
888 #else
889 	if (sa == NULL)
890 		return;
891 #endif
892 }
893 
894 static void
usage(void)895 usage(void)
896 {
897 
898 	fprintf(stderr,
899 		"usage: syslogd [-468ACcdFHknosTuv] [-a allowed_peer]\n"
900 		"               [-b bind_address] [-f config_file]\n"
901 		"               [-l [mode:]path] [-m mark_interval]\n"
902 		"               [-O format] [-P pid_file] [-p log_socket]\n"
903 		"               [-S logpriv_socket]\n");
904 	exit(1);
905 }
906 
907 /*
908  * Removes characters from log messages that are unsafe to display.
909  * TODO: Permit UTF-8 strings that include a BOM per RFC 5424?
910  */
911 static void
parsemsg_remove_unsafe_characters(const char * in,char * out,size_t outlen)912 parsemsg_remove_unsafe_characters(const char *in, char *out, size_t outlen)
913 {
914 	char *q;
915 	int c;
916 
917 	q = out;
918 	while ((c = (unsigned char)*in++) != '\0' && q < out + outlen - 4) {
919 		if (mask_C1 && (c & 0x80) && c < 0xA0) {
920 			c &= 0x7F;
921 			*q++ = 'M';
922 			*q++ = '-';
923 		}
924 		if (isascii(c) && iscntrl(c)) {
925 			if (c == '\n') {
926 				*q++ = ' ';
927 			} else if (c == '\t') {
928 				*q++ = '\t';
929 			} else {
930 				*q++ = '^';
931 				*q++ = c ^ 0100;
932 			}
933 		} else {
934 			*q++ = c;
935 		}
936 	}
937 	*q = '\0';
938 }
939 
940 /*
941  * Parses a syslog message according to RFC 5424, assuming that PRI and
942  * VERSION (i.e., "<%d>1 ") have already been parsed by parsemsg(). The
943  * parsed result is passed to logmsg().
944  */
945 static void
parsemsg_rfc5424(const char * from,int pri,char * msg)946 parsemsg_rfc5424(const char *from, int pri, char *msg)
947 {
948 	const struct logtime *timestamp;
949 	struct logtime timestamp_remote;
950 	const char *omsg, *hostname, *app_name, *procid, *msgid,
951 	    *structured_data;
952 	char line[MAXLINE + 1];
953 
954 #define	FAIL_IF(field, expr) do {					\
955 	if (expr) {							\
956 		dprintf("Failed to parse " field " from %s: %s\n",	\
957 		    from, omsg);					\
958 		return;							\
959 	}								\
960 } while (0)
961 #define	PARSE_CHAR(field, sep) do {					\
962 	FAIL_IF(field, *msg != sep);					\
963 	++msg;								\
964 } while (0)
965 #define	IF_NOT_NILVALUE(var)						\
966 	if (msg[0] == '-' && msg[1] == ' ') {				\
967 		msg += 2;						\
968 		var = NULL;						\
969 	} else if (msg[0] == '-' && msg[1] == '\0') {			\
970 		++msg;							\
971 		var = NULL;						\
972 	} else
973 
974 	omsg = msg;
975 	IF_NOT_NILVALUE(timestamp) {
976 		/* Parse RFC 3339-like timestamp. */
977 #define	PARSE_NUMBER(dest, length, min, max) do {			\
978 	int i, v;							\
979 									\
980 	v = 0;								\
981 	for (i = 0; i < length; ++i) {					\
982 		FAIL_IF("TIMESTAMP", *msg < '0' || *msg > '9');		\
983 		v = v * 10 + *msg++ - '0';				\
984 	}								\
985 	FAIL_IF("TIMESTAMP", v < min || v > max);			\
986 	dest = v;							\
987 } while (0)
988 		/* Date and time. */
989 		memset(&timestamp_remote, 0, sizeof(timestamp_remote));
990 		PARSE_NUMBER(timestamp_remote.tm.tm_year, 4, 0, 9999);
991 		timestamp_remote.tm.tm_year -= 1900;
992 		PARSE_CHAR("TIMESTAMP", '-');
993 		PARSE_NUMBER(timestamp_remote.tm.tm_mon, 2, 1, 12);
994 		--timestamp_remote.tm.tm_mon;
995 		PARSE_CHAR("TIMESTAMP", '-');
996 		PARSE_NUMBER(timestamp_remote.tm.tm_mday, 2, 1, 31);
997 		PARSE_CHAR("TIMESTAMP", 'T');
998 		PARSE_NUMBER(timestamp_remote.tm.tm_hour, 2, 0, 23);
999 		PARSE_CHAR("TIMESTAMP", ':');
1000 		PARSE_NUMBER(timestamp_remote.tm.tm_min, 2, 0, 59);
1001 		PARSE_CHAR("TIMESTAMP", ':');
1002 		PARSE_NUMBER(timestamp_remote.tm.tm_sec, 2, 0, 59);
1003 		/* Perform normalization. */
1004 		timegm(&timestamp_remote.tm);
1005 		/* Optional: fractional seconds. */
1006 		if (msg[0] == '.' && msg[1] >= '0' && msg[1] <= '9') {
1007 			int i;
1008 
1009 			++msg;
1010 			for (i = 100000; i != 0; i /= 10) {
1011 				if (*msg < '0' || *msg > '9')
1012 					break;
1013 				timestamp_remote.usec += (*msg++ - '0') * i;
1014 			}
1015 		}
1016 		/* Timezone. */
1017 		if (*msg == 'Z') {
1018 			/* UTC. */
1019 			++msg;
1020 		} else {
1021 			int sign, tz_hour, tz_min;
1022 
1023 			/* Local time zone offset. */
1024 			FAIL_IF("TIMESTAMP", *msg != '-' && *msg != '+');
1025 			sign = *msg++ == '-' ? -1 : 1;
1026 			PARSE_NUMBER(tz_hour, 2, 0, 23);
1027 			PARSE_CHAR("TIMESTAMP", ':');
1028 			PARSE_NUMBER(tz_min, 2, 0, 59);
1029 			timestamp_remote.tm.tm_gmtoff =
1030 			    sign * (tz_hour * 3600 + tz_min * 60);
1031 		}
1032 #undef PARSE_NUMBER
1033 		PARSE_CHAR("TIMESTAMP", ' ');
1034 		timestamp = RemoteAddDate ? NULL : &timestamp_remote;
1035 	}
1036 
1037 	/* String fields part of the HEADER. */
1038 #define	PARSE_STRING(field, var)					\
1039 	IF_NOT_NILVALUE(var) {						\
1040 		var = msg;						\
1041 		while (*msg >= '!' && *msg <= '~')			\
1042 			++msg;						\
1043 		FAIL_IF(field, var == msg);				\
1044 		PARSE_CHAR(field, ' ');					\
1045 		msg[-1] = '\0';						\
1046 	}
1047 	PARSE_STRING("HOSTNAME", hostname);
1048 	if (hostname == NULL || !RemoteHostname)
1049 		hostname = from;
1050 	PARSE_STRING("APP-NAME", app_name);
1051 	PARSE_STRING("PROCID", procid);
1052 	PARSE_STRING("MSGID", msgid);
1053 #undef PARSE_STRING
1054 
1055 	/* Structured data. */
1056 #define	PARSE_SD_NAME() do {						\
1057 	const char *start;						\
1058 									\
1059 	start = msg;							\
1060 	while (*msg >= '!' && *msg <= '~' && *msg != '=' &&		\
1061 	    *msg != ']' && *msg != '"')					\
1062 		++msg;							\
1063 	FAIL_IF("STRUCTURED-NAME", start == msg);			\
1064 } while (0)
1065 	IF_NOT_NILVALUE(structured_data) {
1066 		/* SD-ELEMENT. */
1067 		while (*msg == '[') {
1068 			++msg;
1069 			/* SD-ID. */
1070 			PARSE_SD_NAME();
1071 			/* SD-PARAM. */
1072 			while (*msg == ' ') {
1073 				++msg;
1074 				/* PARAM-NAME. */
1075 				PARSE_SD_NAME();
1076 				PARSE_CHAR("STRUCTURED-NAME", '=');
1077 				PARSE_CHAR("STRUCTURED-NAME", '"');
1078 				while (*msg != '"') {
1079 					FAIL_IF("STRUCTURED-NAME",
1080 					    *msg == '\0');
1081 					if (*msg++ == '\\') {
1082 						FAIL_IF("STRUCTURED-NAME",
1083 						    *msg == '\0');
1084 						++msg;
1085 					}
1086 				}
1087 				++msg;
1088 			}
1089 			PARSE_CHAR("STRUCTURED-NAME", ']');
1090 		}
1091 		PARSE_CHAR("STRUCTURED-NAME", ' ');
1092 		msg[-1] = '\0';
1093 	}
1094 #undef PARSE_SD_NAME
1095 
1096 #undef FAIL_IF
1097 #undef PARSE_CHAR
1098 #undef IF_NOT_NILVALUE
1099 
1100 	parsemsg_remove_unsafe_characters(msg, line, sizeof(line));
1101 	logmsg(pri, timestamp, hostname, app_name, procid, msgid,
1102 	    structured_data, line, 0);
1103 }
1104 
1105 /*
1106  * Trims the application name ("TAG" in RFC 3164 terminology) and
1107  * process ID from a message if present.
1108  */
1109 static void
parsemsg_rfc3164_app_name_procid(char ** msg,const char ** app_name,const char ** procid)1110 parsemsg_rfc3164_app_name_procid(char **msg, const char **app_name,
1111     const char **procid) {
1112 	char *m, *app_name_begin, *procid_begin;
1113 	size_t app_name_length, procid_length;
1114 
1115 	m = *msg;
1116 
1117 	/* Application name. */
1118 	app_name_begin = m;
1119 	app_name_length = strspn(m,
1120 	    "abcdefghijklmnopqrstuvwxyz"
1121 	    "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
1122 	    "0123456789"
1123 	    "_-/");
1124 	if (app_name_length == 0)
1125 		goto bad;
1126 	m += app_name_length;
1127 
1128 	/* Process identifier (optional). */
1129 	if (*m == '[') {
1130 		procid_begin = ++m;
1131 		procid_length = strspn(m, "0123456789");
1132 		if (procid_length == 0)
1133 			goto bad;
1134 		m += procid_length;
1135 		if (*m++ != ']')
1136 			goto bad;
1137 	} else {
1138 		procid_begin = NULL;
1139 		procid_length = 0;
1140 	}
1141 
1142 	/* Separator. */
1143 	if (m[0] != ':' || m[1] != ' ')
1144 		goto bad;
1145 
1146 	/* Split strings from input. */
1147 	app_name_begin[app_name_length] = '\0';
1148 	if (procid_begin != 0)
1149 		procid_begin[procid_length] = '\0';
1150 
1151 	*msg = m + 2;
1152 	*app_name = app_name_begin;
1153 	*procid = procid_begin;
1154 	return;
1155 bad:
1156 	*app_name = NULL;
1157 	*procid = NULL;
1158 }
1159 
1160 /*
1161  * Parses a syslog message according to RFC 3164, assuming that PRI
1162  * (i.e., "<%d>") has already been parsed by parsemsg(). The parsed
1163  * result is passed to logmsg().
1164  */
1165 static void
parsemsg_rfc3164(const char * from,int pri,char * msg)1166 parsemsg_rfc3164(const char *from, int pri, char *msg)
1167 {
1168 	struct tm tm_parsed;
1169 	const struct logtime *timestamp;
1170 	struct logtime timestamp_remote;
1171 	const char *app_name, *procid;
1172 	size_t i, msglen;
1173 	char line[MAXLINE + 1];
1174 
1175 	/*
1176 	 * Parse the TIMESTAMP provided by the remote side. If none is
1177 	 * found, assume this is not an RFC 3164 formatted message,
1178 	 * only containing a TAG and a MSG.
1179 	 */
1180 	timestamp = NULL;
1181 	if (strptime(msg, RFC3164_DATEFMT, &tm_parsed) ==
1182 	    msg + RFC3164_DATELEN && msg[RFC3164_DATELEN] == ' ') {
1183 		msg += RFC3164_DATELEN + 1;
1184 		if (!RemoteAddDate) {
1185 			struct tm tm_now;
1186 			time_t t_now;
1187 			int year;
1188 
1189 			/*
1190 			 * As the timestamp does not contain the year
1191 			 * number, daylight saving time information, nor
1192 			 * a time zone, attempt to infer it. Due to
1193 			 * clock skews, the timestamp may even be part
1194 			 * of the next year. Use the last year for which
1195 			 * the timestamp is at most one week in the
1196 			 * future.
1197 			 *
1198 			 * This loop can only run for at most three
1199 			 * iterations before terminating.
1200 			 */
1201 			t_now = time(NULL);
1202 			localtime_r(&t_now, &tm_now);
1203 			for (year = tm_now.tm_year + 1;; --year) {
1204 				assert(year >= tm_now.tm_year - 1);
1205 				timestamp_remote.tm = tm_parsed;
1206 				timestamp_remote.tm.tm_year = year;
1207 				timestamp_remote.tm.tm_isdst = -1;
1208 				timestamp_remote.usec = 0;
1209 				if (mktime(&timestamp_remote.tm) <
1210 				    t_now + 7 * 24 * 60 * 60)
1211 					break;
1212 			}
1213 			timestamp = &timestamp_remote;
1214 		}
1215 
1216 		/*
1217 		 * A single space character MUST also follow the HOSTNAME field.
1218 		 */
1219 		msglen = strlen(msg);
1220 		for (i = 0; i < MIN(MAXHOSTNAMELEN, msglen); i++) {
1221 			if (msg[i] == ' ') {
1222 				if (RemoteHostname) {
1223 					msg[i] = '\0';
1224 					from = msg;
1225 				}
1226 				msg += i + 1;
1227 				break;
1228 			}
1229 			/*
1230 			 * Support non RFC compliant messages, without hostname.
1231 			 */
1232 			if (msg[i] == ':')
1233 				break;
1234 		}
1235 		if (i == MIN(MAXHOSTNAMELEN, msglen)) {
1236 			dprintf("Invalid HOSTNAME from %s: %s\n", from, msg);
1237 			return;
1238 		}
1239 	}
1240 
1241 	/* Remove the TAG, if present. */
1242 	parsemsg_rfc3164_app_name_procid(&msg, &app_name, &procid);
1243 	parsemsg_remove_unsafe_characters(msg, line, sizeof(line));
1244 	logmsg(pri, timestamp, from, app_name, procid, NULL, NULL, line, 0);
1245 }
1246 
1247 /*
1248  * Takes a raw input line, extracts PRI and determines whether the
1249  * message is formatted according to RFC 3164 or RFC 5424. Continues
1250  * parsing of addition fields in the message according to those
1251  * standards and prints the message on the appropriate log files.
1252  */
1253 static void
parsemsg(const char * from,char * msg)1254 parsemsg(const char *from, char *msg)
1255 {
1256 	char *q;
1257 	long n;
1258 	size_t i;
1259 	int pri;
1260 
1261 	/* Parse PRI. */
1262 	if (msg[0] != '<' || !isdigit(msg[1])) {
1263 		dprintf("Invalid PRI from %s\n", from);
1264 		return;
1265 	}
1266 	for (i = 2; i <= 4; i++) {
1267 		if (msg[i] == '>')
1268 			break;
1269 		if (!isdigit(msg[i])) {
1270 			dprintf("Invalid PRI header from %s\n", from);
1271 			return;
1272 		}
1273 	}
1274 	if (msg[i] != '>') {
1275 		dprintf("Invalid PRI header from %s\n", from);
1276 		return;
1277 	}
1278 	errno = 0;
1279 	n = strtol(msg + 1, &q, 10);
1280 	if (errno != 0 || *q != msg[i] || n < 0 || n >= INT_MAX) {
1281 		dprintf("Invalid PRI %ld from %s: %s\n",
1282 		    n, from, strerror(errno));
1283 		return;
1284 	}
1285 	pri = n;
1286 	if (pri &~ (LOG_FACMASK|LOG_PRIMASK))
1287 		pri = DEFUPRI;
1288 
1289 	/*
1290 	 * Don't allow users to log kernel messages.
1291 	 * NOTE: since LOG_KERN == 0 this will also match
1292 	 *       messages with no facility specified.
1293 	 */
1294 	if ((pri & LOG_FACMASK) == LOG_KERN && !KeepKernFac)
1295 		pri = LOG_MAKEPRI(LOG_USER, LOG_PRI(pri));
1296 
1297 	/* Parse VERSION. */
1298 	msg += i + 1;
1299 	if (msg[0] == '1' && msg[1] == ' ')
1300 		parsemsg_rfc5424(from, pri, msg + 2);
1301 	else
1302 		parsemsg_rfc3164(from, pri, msg);
1303 }
1304 
1305 /*
1306  * Read /dev/klog while data are available, split into lines.
1307  */
1308 static int
socklist_recv_file(struct socklist * sl)1309 socklist_recv_file(struct socklist *sl)
1310 {
1311 	char *p, *q, line[MAXLINE + 1];
1312 	int len, i;
1313 
1314 	len = 0;
1315 	for (;;) {
1316 		i = read(sl->sl_socket, line + len, MAXLINE - 1 - len);
1317 		if (i > 0) {
1318 			line[i + len] = '\0';
1319 		} else {
1320 			if (i < 0 && errno != EINTR && errno != EAGAIN) {
1321 				logerror("klog");
1322 				close(sl->sl_socket);
1323 				sl->sl_socket = -1;
1324 			}
1325 			break;
1326 		}
1327 
1328 		for (p = line; (q = strchr(p, '\n')) != NULL; p = q + 1) {
1329 			*q = '\0';
1330 			printsys(p);
1331 		}
1332 		len = strlen(p);
1333 		if (len >= MAXLINE - 1) {
1334 			printsys(p);
1335 			len = 0;
1336 		}
1337 		if (len > 0)
1338 			memmove(line, p, len + 1);
1339 	}
1340 	if (len > 0)
1341 		printsys(line);
1342 
1343 	return (len);
1344 }
1345 
1346 /*
1347  * Take a raw input line from /dev/klog, format similar to syslog().
1348  */
1349 static void
printsys(char * msg)1350 printsys(char *msg)
1351 {
1352 	char *p, *q;
1353 	long n;
1354 	int flags, isprintf, pri;
1355 
1356 	flags = SYNC_FILE;	/* fsync after write */
1357 	p = msg;
1358 	pri = DEFSPRI;
1359 	isprintf = 1;
1360 	if (*p == '<') {
1361 		errno = 0;
1362 		n = strtol(p + 1, &q, 10);
1363 		if (*q == '>' && n >= 0 && n < INT_MAX && errno == 0) {
1364 			p = q + 1;
1365 			pri = n;
1366 			isprintf = 0;
1367 		}
1368 	}
1369 	/*
1370 	 * Kernel printf's and LOG_CONSOLE messages have been displayed
1371 	 * on the console already.
1372 	 */
1373 	if (isprintf || (pri & LOG_FACMASK) == LOG_CONSOLE)
1374 		flags |= IGN_CONS;
1375 	if (pri &~ (LOG_FACMASK|LOG_PRIMASK))
1376 		pri = DEFSPRI;
1377 	logmsg(pri, NULL, LocalHostName, "kernel", NULL, NULL, NULL, p, flags);
1378 }
1379 
1380 static time_t	now;
1381 
1382 /*
1383  * Match a program or host name against a specification.
1384  * Return a non-0 value if the message must be ignored
1385  * based on the specification.
1386  */
1387 static int
skip_message(const char * name,const char * spec,int checkcase)1388 skip_message(const char *name, const char *spec, int checkcase)
1389 {
1390 	const char *s;
1391 	char prev, next;
1392 	int exclude = 0;
1393 	/* Behaviour on explicit match */
1394 
1395 	if (spec == NULL)
1396 		return 0;
1397 	switch (*spec) {
1398 	case '-':
1399 		exclude = 1;
1400 		/*FALLTHROUGH*/
1401 	case '+':
1402 		spec++;
1403 		break;
1404 	default:
1405 		break;
1406 	}
1407 	if (checkcase)
1408 		s = strstr (spec, name);
1409 	else
1410 		s = strcasestr (spec, name);
1411 
1412 	if (s != NULL) {
1413 		prev = (s == spec ? ',' : *(s - 1));
1414 		next = *(s + strlen (name));
1415 
1416 		if (prev == ',' && (next == '\0' || next == ','))
1417 			/* Explicit match: skip iff the spec is an
1418 			   exclusive one. */
1419 			return exclude;
1420 	}
1421 
1422 	/* No explicit match for this name: skip the message iff
1423 	   the spec is an inclusive one. */
1424 	return !exclude;
1425 }
1426 
1427 /*
1428  * Logs a message to the appropriate log files, users, etc. based on the
1429  * priority. Log messages are always formatted according to RFC 3164,
1430  * even if they were in RFC 5424 format originally, The MSGID and
1431  * STRUCTURED-DATA fields are thus discarded for the time being.
1432  */
1433 static void
logmsg(int pri,const struct logtime * timestamp,const char * hostname,const char * app_name,const char * procid,const char * msgid,const char * structured_data,const char * msg,int flags)1434 logmsg(int pri, const struct logtime *timestamp, const char *hostname,
1435     const char *app_name, const char *procid, const char *msgid,
1436     const char *structured_data, const char *msg, int flags)
1437 {
1438 	struct timeval tv;
1439 	struct logtime timestamp_now;
1440 	struct filed *f;
1441 	size_t savedlen;
1442 	int fac, prilev;
1443 	char saved[MAXSVLINE];
1444 
1445 	dprintf("logmsg: pri %o, flags %x, from %s, msg %s\n",
1446 	    pri, flags, hostname, msg);
1447 
1448 	(void)gettimeofday(&tv, NULL);
1449 	now = tv.tv_sec;
1450 	if (timestamp == NULL) {
1451 		localtime_r(&now, &timestamp_now.tm);
1452 		timestamp_now.usec = tv.tv_usec;
1453 		timestamp = &timestamp_now;
1454 	}
1455 
1456 	/* extract facility and priority level */
1457 	if (flags & MARK)
1458 		fac = LOG_NFACILITIES;
1459 	else
1460 		fac = LOG_FAC(pri);
1461 
1462 	/* Check maximum facility number. */
1463 	if (fac > LOG_NFACILITIES)
1464 		return;
1465 
1466 	prilev = LOG_PRI(pri);
1467 
1468 	/* log the message to the particular outputs */
1469 	if (!Initialized) {
1470 		f = &consfile;
1471 		/*
1472 		 * Open in non-blocking mode to avoid hangs during open
1473 		 * and close(waiting for the port to drain).
1474 		 */
1475 		f->f_file = open(ctty, O_WRONLY | O_NONBLOCK, 0);
1476 
1477 		if (f->f_file >= 0) {
1478 			f->f_lasttime = *timestamp;
1479 			fprintlog_first(f, hostname, app_name, procid, msgid,
1480 			    structured_data, msg, flags);
1481 			close(f->f_file);
1482 			f->f_file = -1;
1483 		}
1484 		return;
1485 	}
1486 
1487 	/*
1488 	 * Store all of the fields of the message, except the timestamp,
1489 	 * in a single string. This string is used to detect duplicate
1490 	 * messages.
1491 	 */
1492 	assert(hostname != NULL);
1493 	assert(msg != NULL);
1494 	savedlen = snprintf(saved, sizeof(saved),
1495 	    "%d %s %s %s %s %s %s", pri, hostname,
1496 	    app_name == NULL ? "-" : app_name, procid == NULL ? "-" : procid,
1497 	    msgid == NULL ? "-" : msgid,
1498 	    structured_data == NULL ? "-" : structured_data, msg);
1499 
1500 	STAILQ_FOREACH(f, &fhead, next) {
1501 		/* skip messages that are incorrect priority */
1502 		if (!(((f->f_pcmp[fac] & PRI_EQ) && (f->f_pmask[fac] == prilev))
1503 		     ||((f->f_pcmp[fac] & PRI_LT) && (f->f_pmask[fac] < prilev))
1504 		     ||((f->f_pcmp[fac] & PRI_GT) && (f->f_pmask[fac] > prilev))
1505 		     )
1506 		    || f->f_pmask[fac] == INTERNAL_NOPRI)
1507 			continue;
1508 
1509 		/* skip messages with the incorrect hostname */
1510 		if (skip_message(hostname, f->f_host, 0))
1511 			continue;
1512 
1513 		/* skip messages with the incorrect program name */
1514 		if (skip_message(app_name == NULL ? "" : app_name,
1515 		    f->f_program, 1))
1516 			continue;
1517 
1518 		/* skip message to console if it has already been printed */
1519 		if (f->f_type == F_CONSOLE && (flags & IGN_CONS))
1520 			continue;
1521 
1522 		/* don't output marks to recently written files */
1523 		if ((flags & MARK) && (now - f->f_time) < MarkInterval / 2)
1524 			continue;
1525 
1526 		/*
1527 		 * suppress duplicate lines to this file
1528 		 */
1529 		if (no_compress - (f->f_type != F_PIPE) < 1 &&
1530 		    (flags & MARK) == 0 && savedlen == f->f_prevlen &&
1531 		    strcmp(saved, f->f_prevline) == 0) {
1532 			f->f_lasttime = *timestamp;
1533 			f->f_prevcount++;
1534 			dprintf("msg repeated %d times, %ld sec of %d\n",
1535 			    f->f_prevcount, (long)(now - f->f_time),
1536 			    repeatinterval[f->f_repeatcount]);
1537 			/*
1538 			 * If domark would have logged this by now,
1539 			 * flush it now (so we don't hold isolated messages),
1540 			 * but back off so we'll flush less often
1541 			 * in the future.
1542 			 */
1543 			if (now > REPEATTIME(f)) {
1544 				fprintlog_successive(f, flags);
1545 				BACKOFF(f);
1546 			}
1547 		} else {
1548 			/* new line, save it */
1549 			if (f->f_prevcount)
1550 				fprintlog_successive(f, 0);
1551 			f->f_repeatcount = 0;
1552 			f->f_prevpri = pri;
1553 			f->f_lasttime = *timestamp;
1554 			static_assert(sizeof(f->f_prevline) == sizeof(saved),
1555 			    "Space to store saved line incorrect");
1556 			(void)strcpy(f->f_prevline, saved);
1557 			f->f_prevlen = savedlen;
1558 			fprintlog_first(f, hostname, app_name, procid, msgid,
1559 			    structured_data, msg, flags);
1560 		}
1561 	}
1562 }
1563 
1564 static void
dofsync(void)1565 dofsync(void)
1566 {
1567 	struct filed *f;
1568 
1569 	STAILQ_FOREACH(f, &fhead, next) {
1570 		if ((f->f_type == F_FILE) &&
1571 		    (f->f_flags & FFLAG_NEEDSYNC)) {
1572 			f->f_flags &= ~FFLAG_NEEDSYNC;
1573 			(void)fsync(f->f_file);
1574 		}
1575 	}
1576 }
1577 
1578 /*
1579  * List of iovecs to which entries can be appended.
1580  * Used for constructing the message to be logged.
1581  */
1582 struct iovlist {
1583 	struct iovec	iov[TTYMSG_IOV_MAX];
1584 	size_t		iovcnt;
1585 	size_t		totalsize;
1586 };
1587 
1588 static void
iovlist_init(struct iovlist * il)1589 iovlist_init(struct iovlist *il)
1590 {
1591 
1592 	il->iovcnt = 0;
1593 	il->totalsize = 0;
1594 }
1595 
1596 static void
iovlist_append(struct iovlist * il,const char * str)1597 iovlist_append(struct iovlist *il, const char *str)
1598 {
1599 	size_t size;
1600 
1601 	/* Discard components if we've run out of iovecs. */
1602 	if (il->iovcnt < nitems(il->iov)) {
1603 		size = strlen(str);
1604 		il->iov[il->iovcnt++] = (struct iovec){
1605 			.iov_base	= __DECONST(char *, str),
1606 			.iov_len	= size,
1607 		};
1608 		il->totalsize += size;
1609 	}
1610 }
1611 
1612 #if defined(INET) || defined(INET6)
1613 static void
iovlist_truncate(struct iovlist * il,size_t size)1614 iovlist_truncate(struct iovlist *il, size_t size)
1615 {
1616 	struct iovec *last;
1617 	size_t diff;
1618 
1619 	while (il->totalsize > size) {
1620 		diff = il->totalsize - size;
1621 		last = &il->iov[il->iovcnt - 1];
1622 		if (diff >= last->iov_len) {
1623 			/* Remove the last iovec entirely. */
1624 			--il->iovcnt;
1625 			il->totalsize -= last->iov_len;
1626 		} else {
1627 			/* Remove the last iovec partially. */
1628 			last->iov_len -= diff;
1629 			il->totalsize -= diff;
1630 		}
1631 	}
1632 }
1633 #endif
1634 
1635 static void
fprintlog_write(struct filed * f,struct iovlist * il,int flags)1636 fprintlog_write(struct filed *f, struct iovlist *il, int flags)
1637 {
1638 	struct msghdr msghdr;
1639 	struct addrinfo *r;
1640 	struct socklist *sl;
1641 	const char *msgret;
1642 	ssize_t lsent;
1643 
1644 	switch (f->f_type) {
1645 	case F_FORW:
1646 		/* Truncate messages to RFC 5426 recommended size. */
1647 		dprintf(" %s", f->fu_forw_hname);
1648 		switch (f->fu_forw_addr->ai_addr->sa_family) {
1649 #ifdef INET
1650 		case AF_INET:
1651 			dprintf(":%d\n",
1652 			    ntohs(satosin(f->fu_forw_addr->ai_addr)->sin_port));
1653 			iovlist_truncate(il, 480);
1654 			break;
1655 #endif
1656 #ifdef INET6
1657 		case AF_INET6:
1658 			dprintf(":%d\n",
1659 			    ntohs(satosin6(f->fu_forw_addr->ai_addr)->sin6_port));
1660 			iovlist_truncate(il, 1180);
1661 			break;
1662 #endif
1663 		default:
1664 			dprintf("\n");
1665 		}
1666 
1667 		lsent = 0;
1668 		for (r = f->fu_forw_addr; r; r = r->ai_next) {
1669 			memset(&msghdr, 0, sizeof(msghdr));
1670 			msghdr.msg_name = r->ai_addr;
1671 			msghdr.msg_namelen = r->ai_addrlen;
1672 			msghdr.msg_iov = il->iov;
1673 			msghdr.msg_iovlen = il->iovcnt;
1674 			STAILQ_FOREACH(sl, &shead, next) {
1675 				if (sl->sl_ss.ss_family == AF_LOCAL ||
1676 				    sl->sl_ss.ss_family == AF_UNSPEC ||
1677 				    sl->sl_socket < 0)
1678 					continue;
1679 				lsent = sendmsg(sl->sl_socket, &msghdr, 0);
1680 				if (lsent == (ssize_t)il->totalsize)
1681 					break;
1682 			}
1683 			if (lsent == (ssize_t)il->totalsize && !send_to_all)
1684 				break;
1685 		}
1686 		dprintf("lsent/totalsize: %zd/%zu\n", lsent, il->totalsize);
1687 		if (lsent != (ssize_t)il->totalsize) {
1688 			int e = errno;
1689 			logerror("sendto");
1690 			errno = e;
1691 			switch (errno) {
1692 			case ENOBUFS:
1693 			case ENETDOWN:
1694 			case ENETUNREACH:
1695 			case EHOSTUNREACH:
1696 			case EHOSTDOWN:
1697 			case EADDRNOTAVAIL:
1698 				break;
1699 			/* case EBADF: */
1700 			/* case EACCES: */
1701 			/* case ENOTSOCK: */
1702 			/* case EFAULT: */
1703 			/* case EMSGSIZE: */
1704 			/* case EAGAIN: */
1705 			/* case ENOBUFS: */
1706 			/* case ECONNREFUSED: */
1707 			default:
1708 				dprintf("removing entry: errno=%d\n", e);
1709 				f->f_type = F_UNUSED;
1710 				break;
1711 			}
1712 		}
1713 		break;
1714 
1715 	case F_FILE:
1716 		dprintf(" %s\n", f->fu_fname);
1717 		iovlist_append(il, "\n");
1718 		if (writev(f->f_file, il->iov, il->iovcnt) < 0) {
1719 			/*
1720 			 * If writev(2) fails for potentially transient errors
1721 			 * like the filesystem being full, ignore it.
1722 			 * Otherwise remove this logfile from the list.
1723 			 */
1724 			if (errno != ENOSPC) {
1725 				int e = errno;
1726 				close_filed(f);
1727 				errno = e;
1728 				logerror(f->fu_fname);
1729 			}
1730 		} else if ((flags & SYNC_FILE) && (f->f_flags & FFLAG_SYNC)) {
1731 			f->f_flags |= FFLAG_NEEDSYNC;
1732 			needdofsync = 1;
1733 		}
1734 		break;
1735 
1736 	case F_PIPE:
1737 		dprintf(" %s\n", f->fu_pipe_pname);
1738 		iovlist_append(il, "\n");
1739 		if (f->fu_pipe_pid == 0) {
1740 			if ((f->f_file = p_open(f->fu_pipe_pname,
1741 						&f->fu_pipe_pid)) < 0) {
1742 				logerror(f->fu_pipe_pname);
1743 				break;
1744 			}
1745 		}
1746 		if (writev(f->f_file, il->iov, il->iovcnt) < 0) {
1747 			int e = errno;
1748 
1749 			deadq_enter(f->fu_pipe_pid, f->fu_pipe_pname);
1750 			close_filed(f);
1751 			errno = e;
1752 			logerror(f->fu_pipe_pname);
1753 		}
1754 		break;
1755 
1756 	case F_CONSOLE:
1757 		if (flags & IGN_CONS) {
1758 			dprintf(" (ignored)\n");
1759 			break;
1760 		}
1761 		/* FALLTHROUGH */
1762 
1763 	case F_TTY:
1764 		dprintf(" %s%s\n", _PATH_DEV, f->fu_fname);
1765 		iovlist_append(il, "\r\n");
1766 		errno = 0;	/* ttymsg() only sometimes returns an errno */
1767 		if ((msgret = ttymsg(il->iov, il->iovcnt, f->fu_fname, 10))) {
1768 			f->f_type = F_UNUSED;
1769 			logerror(msgret);
1770 		}
1771 		break;
1772 
1773 	case F_USERS:
1774 	case F_WALL:
1775 		dprintf("\n");
1776 		iovlist_append(il, "\r\n");
1777 		wallmsg(f, il->iov, il->iovcnt);
1778 		break;
1779 	}
1780 }
1781 
1782 static void
fprintlog_rfc5424(struct filed * f,const char * hostname,const char * app_name,const char * procid,const char * msgid,const char * structured_data,const char * msg,int flags)1783 fprintlog_rfc5424(struct filed *f, const char *hostname, const char *app_name,
1784     const char *procid, const char *msgid, const char *structured_data,
1785     const char *msg, int flags)
1786 {
1787 	struct iovlist il;
1788 	suseconds_t usec;
1789 	int i;
1790 	char timebuf[33], priority_number[5];
1791 
1792 	iovlist_init(&il);
1793 	if (f->f_type == F_WALL)
1794 		iovlist_append(&il, "\r\n\aMessage from syslogd ...\r\n");
1795 	iovlist_append(&il, "<");
1796 	snprintf(priority_number, sizeof(priority_number), "%d", f->f_prevpri);
1797 	iovlist_append(&il, priority_number);
1798 	iovlist_append(&il, ">1 ");
1799 	if (strftime(timebuf, sizeof(timebuf), "%FT%T.______%z",
1800 	    &f->f_lasttime.tm) == sizeof(timebuf) - 2) {
1801 		/* Add colon to the time zone offset, which %z doesn't do. */
1802 		timebuf[32] = '\0';
1803 		timebuf[31] = timebuf[30];
1804 		timebuf[30] = timebuf[29];
1805 		timebuf[29] = ':';
1806 
1807 		/* Overwrite space for microseconds with actual value. */
1808 		usec = f->f_lasttime.usec;
1809 		for (i = 25; i >= 20; --i) {
1810 			timebuf[i] = usec % 10 + '0';
1811 			usec /= 10;
1812 		}
1813 		iovlist_append(&il, timebuf);
1814 	} else
1815 		iovlist_append(&il, "-");
1816 	iovlist_append(&il, " ");
1817 	iovlist_append(&il, hostname);
1818 	iovlist_append(&il, " ");
1819 	iovlist_append(&il, app_name == NULL ? "-" : app_name);
1820 	iovlist_append(&il, " ");
1821 	iovlist_append(&il, procid == NULL ? "-" : procid);
1822 	iovlist_append(&il, " ");
1823 	iovlist_append(&il, msgid == NULL ? "-" : msgid);
1824 	iovlist_append(&il, " ");
1825 	iovlist_append(&il, structured_data == NULL ? "-" : structured_data);
1826 	iovlist_append(&il, " ");
1827 	iovlist_append(&il, msg);
1828 
1829 	fprintlog_write(f, &il, flags);
1830 }
1831 
1832 static void
fprintlog_rfc3164(struct filed * f,const char * hostname,const char * app_name,const char * procid,const char * msg,int flags)1833 fprintlog_rfc3164(struct filed *f, const char *hostname, const char *app_name,
1834     const char *procid, const char *msg, int flags)
1835 {
1836 	struct iovlist il;
1837 	const CODE *c;
1838 	int facility, priority;
1839 	char timebuf[RFC3164_DATELEN + 1], facility_number[5],
1840 	    priority_number[5];
1841 	bool facility_found, priority_found;
1842 
1843 	if (strftime(timebuf, sizeof(timebuf), RFC3164_DATEFMT,
1844 	    &f->f_lasttime.tm) == 0)
1845 		timebuf[0] = '\0';
1846 
1847 	iovlist_init(&il);
1848 	switch (f->f_type) {
1849 	case F_FORW:
1850 		/* Message forwarded over the network. */
1851 		iovlist_append(&il, "<");
1852 		snprintf(priority_number, sizeof(priority_number), "%d",
1853 		    f->f_prevpri);
1854 		iovlist_append(&il, priority_number);
1855 		iovlist_append(&il, ">");
1856 		iovlist_append(&il, timebuf);
1857 		if (strcasecmp(hostname, LocalHostName) != 0) {
1858 			iovlist_append(&il, " Forwarded from ");
1859 			iovlist_append(&il, hostname);
1860 			iovlist_append(&il, ":");
1861 		}
1862 		iovlist_append(&il, " ");
1863 		break;
1864 
1865 	case F_WALL:
1866 		/* Message written to terminals. */
1867 		iovlist_append(&il, "\r\n\aMessage from syslogd@");
1868 		iovlist_append(&il, hostname);
1869 		iovlist_append(&il, " at ");
1870 		iovlist_append(&il, timebuf);
1871 		iovlist_append(&il, " ...\r\n");
1872 		break;
1873 
1874 	default:
1875 		/* Message written to files. */
1876 		iovlist_append(&il, timebuf);
1877 		iovlist_append(&il, " ");
1878 
1879 		if (LogFacPri) {
1880 			iovlist_append(&il, "<");
1881 
1882 			facility = f->f_prevpri & LOG_FACMASK;
1883 			facility_found = false;
1884 			if (LogFacPri > 1) {
1885 				for (c = facilitynames; c->c_name; c++) {
1886 					if (c->c_val == facility) {
1887 						iovlist_append(&il, c->c_name);
1888 						facility_found = true;
1889 						break;
1890 					}
1891 				}
1892 			}
1893 			if (!facility_found) {
1894 				snprintf(facility_number,
1895 				    sizeof(facility_number), "%d",
1896 				    LOG_FAC(facility));
1897 				iovlist_append(&il, facility_number);
1898 			}
1899 
1900 			iovlist_append(&il, ".");
1901 
1902 			priority = LOG_PRI(f->f_prevpri);
1903 			priority_found = false;
1904 			if (LogFacPri > 1) {
1905 				for (c = prioritynames; c->c_name; c++) {
1906 					if (c->c_val == priority) {
1907 						iovlist_append(&il, c->c_name);
1908 						priority_found = true;
1909 						break;
1910 					}
1911 				}
1912 			}
1913 			if (!priority_found) {
1914 				snprintf(priority_number,
1915 				    sizeof(priority_number), "%d", priority);
1916 				iovlist_append(&il, priority_number);
1917 			}
1918 
1919 			iovlist_append(&il, "> ");
1920 		}
1921 
1922 		iovlist_append(&il, hostname);
1923 		iovlist_append(&il, " ");
1924 		break;
1925 	}
1926 
1927 	/* Message body with application name and process ID prefixed. */
1928 	if (app_name != NULL) {
1929 		iovlist_append(&il, app_name);
1930 		if (procid != NULL) {
1931 			iovlist_append(&il, "[");
1932 			iovlist_append(&il, procid);
1933 			iovlist_append(&il, "]");
1934 		}
1935 		iovlist_append(&il, ": ");
1936 	}
1937 	iovlist_append(&il, msg);
1938 
1939 	fprintlog_write(f, &il, flags);
1940 }
1941 
1942 static void
fprintlog_first(struct filed * f,const char * hostname,const char * app_name,const char * procid,const char * msgid __unused,const char * structured_data __unused,const char * msg,int flags)1943 fprintlog_first(struct filed *f, const char *hostname, const char *app_name,
1944     const char *procid, const char *msgid __unused,
1945     const char *structured_data __unused, const char *msg, int flags)
1946 {
1947 
1948 	dprintf("Logging to %s", TypeNames[f->f_type]);
1949 	f->f_time = now;
1950 	f->f_prevcount = 0;
1951 	if (f->f_type == F_UNUSED) {
1952 		dprintf("\n");
1953 		return;
1954 	}
1955 
1956 	if (RFC3164OutputFormat)
1957 		fprintlog_rfc3164(f, hostname, app_name, procid, msg, flags);
1958 	else
1959 		fprintlog_rfc5424(f, hostname, app_name, procid, msgid,
1960 		    structured_data, msg, flags);
1961 }
1962 
1963 /*
1964  * Prints a message to a log file that the previously logged message was
1965  * received multiple times.
1966  */
1967 static void
fprintlog_successive(struct filed * f,int flags)1968 fprintlog_successive(struct filed *f, int flags)
1969 {
1970 	char msg[100];
1971 
1972 	assert(f->f_prevcount > 0);
1973 	snprintf(msg, sizeof(msg), "last message repeated %d times",
1974 	    f->f_prevcount);
1975 	fprintlog_first(f, LocalHostName, "syslogd", NULL, NULL, NULL, msg,
1976 	    flags);
1977 }
1978 
1979 /*
1980  *  WALLMSG -- Write a message to the world at large
1981  *
1982  *	Write the specified message to either the entire
1983  *	world, or a list of approved users.
1984  */
1985 static void
wallmsg(struct filed * f,struct iovec * iov,const int iovlen)1986 wallmsg(struct filed *f, struct iovec *iov, const int iovlen)
1987 {
1988 	static int reenter;			/* avoid calling ourselves */
1989 	struct utmpx *ut;
1990 	int i;
1991 	const char *p;
1992 
1993 	if (reenter++)
1994 		return;
1995 	setutxent();
1996 	/* NOSTRICT */
1997 	while ((ut = getutxent()) != NULL) {
1998 		if (ut->ut_type != USER_PROCESS)
1999 			continue;
2000 		if (f->f_type == F_WALL) {
2001 			if ((p = ttymsg(iov, iovlen, ut->ut_line,
2002 			    TTYMSGTIME)) != NULL) {
2003 				errno = 0;	/* already in msg */
2004 				logerror(p);
2005 			}
2006 			continue;
2007 		}
2008 		/* should we send the message to this user? */
2009 		for (i = 0; i < MAXUNAMES; i++) {
2010 			if (!f->fu_uname[i][0])
2011 				break;
2012 			if (!strcmp(f->fu_uname[i], ut->ut_user)) {
2013 				if ((p = ttymsg_check(iov, iovlen, ut->ut_line,
2014 				    TTYMSGTIME)) != NULL) {
2015 					errno = 0;	/* already in msg */
2016 					logerror(p);
2017 				}
2018 				break;
2019 			}
2020 		}
2021 	}
2022 	endutxent();
2023 	reenter = 0;
2024 }
2025 
2026 /*
2027  * Wrapper routine for ttymsg() that checks the terminal for messages enabled.
2028  */
2029 static const char *
ttymsg_check(struct iovec * iov,int iovcnt,char * line,int tmout)2030 ttymsg_check(struct iovec *iov, int iovcnt, char *line, int tmout)
2031 {
2032 	static char device[1024];
2033 	static char errbuf[1024];
2034 	struct stat sb;
2035 
2036 	(void) snprintf(device, sizeof(device), "%s%s", _PATH_DEV, line);
2037 
2038 	if (stat(device, &sb) < 0) {
2039 		(void) snprintf(errbuf, sizeof(errbuf),
2040 		    "%s: %s", device, strerror(errno));
2041 		return (errbuf);
2042 	}
2043 	if ((sb.st_mode & S_IWGRP) == 0)
2044 		/* Messages disabled. */
2045 		return (NULL);
2046 	return ttymsg(iov, iovcnt, line, tmout);
2047 }
2048 
2049 static void
reapchild(int signo __unused)2050 reapchild(int signo __unused)
2051 {
2052 	int status;
2053 	pid_t pid;
2054 	struct filed *f;
2055 
2056 	while ((pid = wait3(&status, WNOHANG, (struct rusage *)NULL)) > 0) {
2057 		/* First, look if it's a process from the dead queue. */
2058 		if (deadq_removebypid(pid))
2059 			continue;
2060 
2061 		/* Now, look in list of active processes. */
2062 		STAILQ_FOREACH(f, &fhead, next) {
2063 			if (f->f_type == F_PIPE &&
2064 			    f->fu_pipe_pid == pid) {
2065 				close_filed(f);
2066 				log_deadchild(pid, status, f->fu_pipe_pname);
2067 				break;
2068 			}
2069 		}
2070 	}
2071 	WantReapchild = 0;
2072 }
2073 
2074 /*
2075  * Return a printable representation of a host address.
2076  */
2077 static const char *
cvthname(struct sockaddr * f)2078 cvthname(struct sockaddr *f)
2079 {
2080 	int error, hl;
2081 	static char hname[NI_MAXHOST], ip[NI_MAXHOST];
2082 
2083 	dprintf("cvthname(%d) len = %d\n", f->sa_family, f->sa_len);
2084 	error = getnameinfo(f, f->sa_len, ip, sizeof(ip), NULL, 0,
2085 		    NI_NUMERICHOST);
2086 	if (error) {
2087 		dprintf("Malformed from address %s\n", gai_strerror(error));
2088 		return ("???");
2089 	}
2090 	dprintf("cvthname(%s)\n", ip);
2091 
2092 	if (!resolve)
2093 		return (ip);
2094 
2095 	error = getnameinfo(f, f->sa_len, hname, sizeof(hname),
2096 		    NULL, 0, NI_NAMEREQD);
2097 	if (error) {
2098 		dprintf("Host name for your address (%s) unknown\n", ip);
2099 		return (ip);
2100 	}
2101 	hl = strlen(hname);
2102 	if (hl > 0 && hname[hl-1] == '.')
2103 		hname[--hl] = '\0';
2104 	trimdomain(hname, hl);
2105 	return (hname);
2106 }
2107 
2108 static void
dodie(int signo)2109 dodie(int signo)
2110 {
2111 
2112 	WantDie = signo;
2113 }
2114 
2115 static void
domark(int signo __unused)2116 domark(int signo __unused)
2117 {
2118 
2119 	MarkSet = 1;
2120 }
2121 
2122 /*
2123  * Print syslogd errors some place.
2124  */
2125 static void
logerror(const char * msg)2126 logerror(const char *msg)
2127 {
2128 	char buf[512];
2129 	static int recursed = 0;
2130 
2131 	/* If there's an error while trying to log an error, give up. */
2132 	if (recursed)
2133 		return;
2134 	recursed++;
2135 	if (errno != 0) {
2136 		(void)snprintf(buf, sizeof(buf), "%s: %s", msg,
2137 		    strerror(errno));
2138 		msg = buf;
2139 	}
2140 	errno = 0;
2141 	dprintf("%s\n", buf);
2142 	logmsg(LOG_SYSLOG|LOG_ERR, NULL, LocalHostName, "syslogd", NULL, NULL,
2143 	    NULL, msg, 0);
2144 	recursed--;
2145 }
2146 
2147 static void
die(int signo)2148 die(int signo)
2149 {
2150 	struct filed *f;
2151 	struct socklist *sl;
2152 	char buf[100];
2153 
2154 	STAILQ_FOREACH(f, &fhead, next) {
2155 		/* flush any pending output */
2156 		if (f->f_prevcount)
2157 			fprintlog_successive(f, 0);
2158 		if (f->f_type == F_PIPE && f->fu_pipe_pid > 0)
2159 			close_filed(f);
2160 	}
2161 	if (signo) {
2162 		dprintf("syslogd: exiting on signal %d\n", signo);
2163 		(void)snprintf(buf, sizeof(buf), "exiting on signal %d", signo);
2164 		errno = 0;
2165 		logerror(buf);
2166 	}
2167 	STAILQ_FOREACH(sl, &shead, next) {
2168 		if (sl->sl_ss.ss_family == AF_LOCAL)
2169 			unlink(sl->sl_peer->pe_name);
2170 	}
2171 	pidfile_remove(pfh);
2172 
2173 	exit(1);
2174 }
2175 
2176 static int
configfiles(const struct dirent * dp)2177 configfiles(const struct dirent *dp)
2178 {
2179 	const char *p;
2180 	size_t ext_len;
2181 
2182 	if (dp->d_name[0] == '.')
2183 		return (0);
2184 
2185 	ext_len = sizeof(include_ext) -1;
2186 
2187 	if (dp->d_namlen <= ext_len)
2188 		return (0);
2189 
2190 	p = &dp->d_name[dp->d_namlen - ext_len];
2191 	if (strcmp(p, include_ext) != 0)
2192 		return (0);
2193 
2194 	return (1);
2195 }
2196 
2197 static void
readconfigfile(FILE * cf,int allow_includes)2198 readconfigfile(FILE *cf, int allow_includes)
2199 {
2200 	FILE *cf2;
2201 	struct filed *f;
2202 	struct dirent **ent;
2203 	char cline[LINE_MAX];
2204 	char host[MAXHOSTNAMELEN];
2205 	char prog[LINE_MAX];
2206 	char file[MAXPATHLEN];
2207 	char *p, *tmp;
2208 	int i, nents;
2209 	size_t include_len;
2210 
2211 	/*
2212 	 *  Foreach line in the conf table, open that file.
2213 	 */
2214 	include_len = sizeof(include_str) -1;
2215 	(void)strlcpy(host, "*", sizeof(host));
2216 	(void)strlcpy(prog, "*", sizeof(prog));
2217 	while (fgets(cline, sizeof(cline), cf) != NULL) {
2218 		/*
2219 		 * check for end-of-section, comments, strip off trailing
2220 		 * spaces and newline character. #!prog is treated specially:
2221 		 * following lines apply only to that program.
2222 		 */
2223 		for (p = cline; isspace(*p); ++p)
2224 			continue;
2225 		if (*p == 0)
2226 			continue;
2227 		if (allow_includes &&
2228 		    strncmp(p, include_str, include_len) == 0 &&
2229 		    isspace(p[include_len])) {
2230 			p += include_len;
2231 			while (isspace(*p))
2232 				p++;
2233 			tmp = p;
2234 			while (*tmp != '\0' && !isspace(*tmp))
2235 				tmp++;
2236 			*tmp = '\0';
2237 			dprintf("Trying to include files in '%s'\n", p);
2238 			nents = scandir(p, &ent, configfiles, alphasort);
2239 			if (nents == -1) {
2240 				dprintf("Unable to open '%s': %s\n", p,
2241 				    strerror(errno));
2242 				continue;
2243 			}
2244 			for (i = 0; i < nents; i++) {
2245 				if (snprintf(file, sizeof(file), "%s/%s", p,
2246 				    ent[i]->d_name) >= (int)sizeof(file)) {
2247 					dprintf("ignoring path too long: "
2248 					    "'%s/%s'\n", p, ent[i]->d_name);
2249 					free(ent[i]);
2250 					continue;
2251 				}
2252 				free(ent[i]);
2253 				cf2 = fopen(file, "r");
2254 				if (cf2 == NULL)
2255 					continue;
2256 				dprintf("reading %s\n", file);
2257 				readconfigfile(cf2, 0);
2258 				fclose(cf2);
2259 			}
2260 			free(ent);
2261 			continue;
2262 		}
2263 		if (*p == '#') {
2264 			p++;
2265 			if (*p != '!' && *p != '+' && *p != '-')
2266 				continue;
2267 		}
2268 		if (*p == '+' || *p == '-') {
2269 			host[0] = *p++;
2270 			while (isspace(*p))
2271 				p++;
2272 			if ((!*p) || (*p == '*')) {
2273 				(void)strlcpy(host, "*", sizeof(host));
2274 				continue;
2275 			}
2276 			if (*p == '@')
2277 				p = LocalHostName;
2278 			for (i = 1; i < MAXHOSTNAMELEN - 1; i++) {
2279 				if (!isalnum(*p) && *p != '.' && *p != '-'
2280 				    && *p != ',' && *p != ':' && *p != '%')
2281 					break;
2282 				host[i] = *p++;
2283 			}
2284 			host[i] = '\0';
2285 			continue;
2286 		}
2287 		if (*p == '!') {
2288 			p++;
2289 			while (isspace(*p)) p++;
2290 			if ((!*p) || (*p == '*')) {
2291 				(void)strlcpy(prog, "*", sizeof(prog));
2292 				continue;
2293 			}
2294 			for (i = 0; i < LINE_MAX - 1; i++) {
2295 				if (!isprint(p[i]) || isspace(p[i]))
2296 					break;
2297 				prog[i] = p[i];
2298 			}
2299 			prog[i] = 0;
2300 			continue;
2301 		}
2302 		for (p = cline + 1; *p != '\0'; p++) {
2303 			if (*p != '#')
2304 				continue;
2305 			if (*(p - 1) == '\\') {
2306 				strcpy(p - 1, p);
2307 				p--;
2308 				continue;
2309 			}
2310 			*p = '\0';
2311 			break;
2312 		}
2313 		for (i = strlen(cline) - 1; i >= 0 && isspace(cline[i]); i--)
2314 			cline[i] = '\0';
2315 		f = cfline(cline, prog, host);
2316 		if (f != NULL)
2317 			addfile(f);
2318 		free(f);
2319 	}
2320 }
2321 
2322 static void
sighandler(int signo)2323 sighandler(int signo)
2324 {
2325 
2326 	/* Send an wake-up signal to the select() loop. */
2327 	write(sigpipe[1], &signo, sizeof(signo));
2328 }
2329 
2330 /*
2331  *  INIT -- Initialize syslogd from configuration table
2332  */
2333 static void
init(int signo)2334 init(int signo)
2335 {
2336 	int i;
2337 	FILE *cf;
2338 	struct filed *f;
2339 	char *p;
2340 	char oldLocalHostName[MAXHOSTNAMELEN];
2341 	char hostMsg[2*MAXHOSTNAMELEN+40];
2342 	char bootfileMsg[LINE_MAX];
2343 
2344 	dprintf("init\n");
2345 	WantInitialize = 0;
2346 
2347 	/*
2348 	 * Load hostname (may have changed).
2349 	 */
2350 	if (signo != 0)
2351 		(void)strlcpy(oldLocalHostName, LocalHostName,
2352 		    sizeof(oldLocalHostName));
2353 	if (gethostname(LocalHostName, sizeof(LocalHostName)))
2354 		err(EX_OSERR, "gethostname() failed");
2355 	if ((p = strchr(LocalHostName, '.')) != NULL) {
2356 		/* RFC 5424 prefers logging FQDNs. */
2357 		if (RFC3164OutputFormat)
2358 			*p = '\0';
2359 		LocalDomain = p + 1;
2360 	} else {
2361 		LocalDomain = "";
2362 	}
2363 
2364 	/*
2365 	 * Load / reload timezone data (in case it changed).
2366 	 *
2367 	 * Just calling tzset() again does not work, the timezone code
2368 	 * caches the result.  However, by setting the TZ variable, one
2369 	 * can defeat the caching and have the timezone code really
2370 	 * reload the timezone data.  Respect any initial setting of
2371 	 * TZ, in case the system is configured specially.
2372 	 */
2373 	dprintf("loading timezone data via tzset()\n");
2374 	if (getenv("TZ")) {
2375 		tzset();
2376 	} else {
2377 		setenv("TZ", ":/etc/localtime", 1);
2378 		tzset();
2379 		unsetenv("TZ");
2380 	}
2381 
2382 	/*
2383 	 *  Close all open log files.
2384 	 */
2385 	Initialized = 0;
2386 	STAILQ_FOREACH(f, &fhead, next) {
2387 		/* flush any pending output */
2388 		if (f->f_prevcount)
2389 			fprintlog_successive(f, 0);
2390 
2391 		switch (f->f_type) {
2392 		case F_FILE:
2393 		case F_FORW:
2394 		case F_CONSOLE:
2395 		case F_TTY:
2396 			close_filed(f);
2397 			break;
2398 		case F_PIPE:
2399 			deadq_enter(f->fu_pipe_pid, f->fu_pipe_pname);
2400 			close_filed(f);
2401 			break;
2402 		}
2403 	}
2404 	while(!STAILQ_EMPTY(&fhead)) {
2405 		f = STAILQ_FIRST(&fhead);
2406 		STAILQ_REMOVE_HEAD(&fhead, next);
2407 		free(f->f_program);
2408 		free(f->f_host);
2409 		free(f);
2410 	}
2411 
2412 	/* open the configuration file */
2413 	if ((cf = fopen(ConfFile, "r")) == NULL) {
2414 		dprintf("cannot open %s\n", ConfFile);
2415 		f = cfline("*.ERR\t/dev/console", "*", "*");
2416 		if (f != NULL)
2417 			addfile(f);
2418 		free(f);
2419 		f = cfline("*.PANIC\t*", "*", "*");
2420 		if (f != NULL)
2421 			addfile(f);
2422 		free(f);
2423 		Initialized = 1;
2424 
2425 		return;
2426 	}
2427 
2428 	readconfigfile(cf, 1);
2429 
2430 	/* close the configuration file */
2431 	(void)fclose(cf);
2432 
2433 	Initialized = 1;
2434 
2435 	if (Debug) {
2436 		int port;
2437 		STAILQ_FOREACH(f, &fhead, next) {
2438 			for (i = 0; i <= LOG_NFACILITIES; i++)
2439 				if (f->f_pmask[i] == INTERNAL_NOPRI)
2440 					printf("X ");
2441 				else
2442 					printf("%d ", f->f_pmask[i]);
2443 			printf("%s: ", TypeNames[f->f_type]);
2444 			switch (f->f_type) {
2445 			case F_FILE:
2446 				printf("%s", f->fu_fname);
2447 				break;
2448 
2449 			case F_CONSOLE:
2450 			case F_TTY:
2451 				printf("%s%s", _PATH_DEV, f->fu_fname);
2452 				break;
2453 
2454 			case F_FORW:
2455 				switch (f->fu_forw_addr->ai_addr->sa_family) {
2456 #ifdef INET
2457 				case AF_INET:
2458 					port = ntohs(satosin(f->fu_forw_addr->ai_addr)->sin_port);
2459 					break;
2460 #endif
2461 #ifdef INET6
2462 				case AF_INET6:
2463 					port = ntohs(satosin6(f->fu_forw_addr->ai_addr)->sin6_port);
2464 					break;
2465 #endif
2466 				default:
2467 					port = 0;
2468 				}
2469 				if (port != 514) {
2470 					printf("%s:%d",
2471 						f->fu_forw_hname, port);
2472 				} else {
2473 					printf("%s", f->fu_forw_hname);
2474 				}
2475 				break;
2476 
2477 			case F_PIPE:
2478 				printf("%s", f->fu_pipe_pname);
2479 				break;
2480 
2481 			case F_USERS:
2482 				for (i = 0; i < MAXUNAMES && *f->fu_uname[i]; i++)
2483 					printf("%s, ", f->fu_uname[i]);
2484 				break;
2485 			}
2486 			if (f->f_program)
2487 				printf(" (%s)", f->f_program);
2488 			printf("\n");
2489 		}
2490 	}
2491 
2492 	logmsg(LOG_SYSLOG | LOG_INFO, NULL, LocalHostName, "syslogd", NULL,
2493 	    NULL, NULL, "restart", 0);
2494 	dprintf("syslogd: restarted\n");
2495 	/*
2496 	 * Log a change in hostname, but only on a restart.
2497 	 */
2498 	if (signo != 0 && strcmp(oldLocalHostName, LocalHostName) != 0) {
2499 		(void)snprintf(hostMsg, sizeof(hostMsg),
2500 		    "hostname changed, \"%s\" to \"%s\"",
2501 		    oldLocalHostName, LocalHostName);
2502 		logmsg(LOG_SYSLOG | LOG_INFO, NULL, LocalHostName, "syslogd",
2503 		    NULL, NULL, NULL, hostMsg, 0);
2504 		dprintf("%s\n", hostMsg);
2505 	}
2506 	/*
2507 	 * Log the kernel boot file if we aren't going to use it as
2508 	 * the prefix, and if this is *not* a restart.
2509 	 */
2510 	if (signo == 0 && !use_bootfile) {
2511 		(void)snprintf(bootfileMsg, sizeof(bootfileMsg),
2512 		    "kernel boot file is %s", bootfile);
2513 		logmsg(LOG_KERN | LOG_INFO, NULL, LocalHostName, "syslogd",
2514 		    NULL, NULL, NULL, bootfileMsg, 0);
2515 		dprintf("%s\n", bootfileMsg);
2516 	}
2517 }
2518 
2519 /*
2520  * Crack a configuration file line
2521  */
2522 static struct filed *
cfline(const char * line,const char * prog,const char * host)2523 cfline(const char *line, const char *prog, const char *host)
2524 {
2525 	struct filed *f;
2526 	struct addrinfo hints, *res;
2527 	int error, i, pri, syncfile;
2528 	const char *p, *q;
2529 	char *bp;
2530 	char buf[MAXLINE], ebuf[100];
2531 
2532 	dprintf("cfline(\"%s\", f, \"%s\", \"%s\")\n", line, prog, host);
2533 
2534 	f = calloc(1, sizeof(*f));
2535 	if (f == NULL) {
2536 		logerror("malloc");
2537 		exit(1);
2538 	}
2539 	errno = 0;	/* keep strerror() stuff out of logerror messages */
2540 
2541 	for (i = 0; i <= LOG_NFACILITIES; i++)
2542 		f->f_pmask[i] = INTERNAL_NOPRI;
2543 
2544 	/* save hostname if any */
2545 	if (host && *host == '*')
2546 		host = NULL;
2547 	if (host) {
2548 		int hl;
2549 
2550 		f->f_host = strdup(host);
2551 		if (f->f_host == NULL) {
2552 			logerror("strdup");
2553 			exit(1);
2554 		}
2555 		hl = strlen(f->f_host);
2556 		if (hl > 0 && f->f_host[hl-1] == '.')
2557 			f->f_host[--hl] = '\0';
2558 		trimdomain(f->f_host, hl);
2559 	}
2560 
2561 	/* save program name if any */
2562 	if (prog && *prog == '*')
2563 		prog = NULL;
2564 	if (prog) {
2565 		f->f_program = strdup(prog);
2566 		if (f->f_program == NULL) {
2567 			logerror("strdup");
2568 			exit(1);
2569 		}
2570 	}
2571 
2572 	/* scan through the list of selectors */
2573 	for (p = line; *p && *p != '\t' && *p != ' ';) {
2574 		int pri_done;
2575 		int pri_cmp;
2576 		int pri_invert;
2577 
2578 		/* find the end of this facility name list */
2579 		for (q = p; *q && *q != '\t' && *q != ' ' && *q++ != '.'; )
2580 			continue;
2581 
2582 		/* get the priority comparison */
2583 		pri_cmp = 0;
2584 		pri_done = 0;
2585 		pri_invert = 0;
2586 		if (*q == '!') {
2587 			pri_invert = 1;
2588 			q++;
2589 		}
2590 		while (!pri_done) {
2591 			switch (*q) {
2592 			case '<':
2593 				pri_cmp |= PRI_LT;
2594 				q++;
2595 				break;
2596 			case '=':
2597 				pri_cmp |= PRI_EQ;
2598 				q++;
2599 				break;
2600 			case '>':
2601 				pri_cmp |= PRI_GT;
2602 				q++;
2603 				break;
2604 			default:
2605 				pri_done++;
2606 				break;
2607 			}
2608 		}
2609 
2610 		/* collect priority name */
2611 		for (bp = buf; *q && !strchr("\t,; ", *q); )
2612 			*bp++ = *q++;
2613 		*bp = '\0';
2614 
2615 		/* skip cruft */
2616 		while (strchr(",;", *q))
2617 			q++;
2618 
2619 		/* decode priority name */
2620 		if (*buf == '*') {
2621 			pri = LOG_PRIMASK;
2622 			pri_cmp = PRI_LT | PRI_EQ | PRI_GT;
2623 		} else {
2624 			/* Ignore trailing spaces. */
2625 			for (i = strlen(buf) - 1; i >= 0 && buf[i] == ' '; i--)
2626 				buf[i] = '\0';
2627 
2628 			pri = decode(buf, prioritynames);
2629 			if (pri < 0) {
2630 				errno = 0;
2631 				(void)snprintf(ebuf, sizeof ebuf,
2632 				    "unknown priority name \"%s\"", buf);
2633 				logerror(ebuf);
2634 				free(f);
2635 				return (NULL);
2636 			}
2637 		}
2638 		if (!pri_cmp)
2639 			pri_cmp = (UniquePriority)
2640 				  ? (PRI_EQ)
2641 				  : (PRI_EQ | PRI_GT)
2642 				  ;
2643 		if (pri_invert)
2644 			pri_cmp ^= PRI_LT | PRI_EQ | PRI_GT;
2645 
2646 		/* scan facilities */
2647 		while (*p && !strchr("\t.; ", *p)) {
2648 			for (bp = buf; *p && !strchr("\t,;. ", *p); )
2649 				*bp++ = *p++;
2650 			*bp = '\0';
2651 
2652 			if (*buf == '*') {
2653 				for (i = 0; i < LOG_NFACILITIES; i++) {
2654 					f->f_pmask[i] = pri;
2655 					f->f_pcmp[i] = pri_cmp;
2656 				}
2657 			} else {
2658 				i = decode(buf, facilitynames);
2659 				if (i < 0) {
2660 					errno = 0;
2661 					(void)snprintf(ebuf, sizeof ebuf,
2662 					    "unknown facility name \"%s\"",
2663 					    buf);
2664 					logerror(ebuf);
2665 					free(f);
2666 					return (NULL);
2667 				}
2668 				f->f_pmask[i >> 3] = pri;
2669 				f->f_pcmp[i >> 3] = pri_cmp;
2670 			}
2671 			while (*p == ',' || *p == ' ')
2672 				p++;
2673 		}
2674 
2675 		p = q;
2676 	}
2677 
2678 	/* skip to action part */
2679 	while (*p == '\t' || *p == ' ')
2680 		p++;
2681 
2682 	if (*p == '-') {
2683 		syncfile = 0;
2684 		p++;
2685 	} else
2686 		syncfile = 1;
2687 
2688 	switch (*p) {
2689 	case '@':
2690 		{
2691 			char *tp;
2692 			char endkey = ':';
2693 			/*
2694 			 * scan forward to see if there is a port defined.
2695 			 * so we can't use strlcpy..
2696 			 */
2697 			i = sizeof(f->fu_forw_hname);
2698 			tp = f->fu_forw_hname;
2699 			p++;
2700 
2701 			/*
2702 			 * an ipv6 address should start with a '[' in that case
2703 			 * we should scan for a ']'
2704 			 */
2705 			if (*p == '[') {
2706 				p++;
2707 				endkey = ']';
2708 			}
2709 			while (*p && (*p != endkey) && (i-- > 0)) {
2710 				*tp++ = *p++;
2711 			}
2712 			if (endkey == ']' && *p == endkey)
2713 				p++;
2714 			*tp = '\0';
2715 		}
2716 		/* See if we copied a domain and have a port */
2717 		if (*p == ':')
2718 			p++;
2719 		else
2720 			p = NULL;
2721 
2722 		hints = (struct addrinfo){
2723 			.ai_family = family,
2724 			.ai_socktype = SOCK_DGRAM
2725 		};
2726 		error = getaddrinfo(f->fu_forw_hname,
2727 				p ? p : "syslog", &hints, &res);
2728 		if (error) {
2729 			logerror(gai_strerror(error));
2730 			break;
2731 		}
2732 		f->fu_forw_addr = res;
2733 		f->f_type = F_FORW;
2734 		break;
2735 
2736 	case '/':
2737 		if ((f->f_file = open(p, logflags, 0600)) < 0) {
2738 			f->f_type = F_UNUSED;
2739 			logerror(p);
2740 			break;
2741 		}
2742 		if (syncfile)
2743 			f->f_flags |= FFLAG_SYNC;
2744 		if (isatty(f->f_file)) {
2745 			if (strcmp(p, ctty) == 0)
2746 				f->f_type = F_CONSOLE;
2747 			else
2748 				f->f_type = F_TTY;
2749 			(void)strlcpy(f->fu_fname, p + sizeof(_PATH_DEV) - 1,
2750 			    sizeof(f->fu_fname));
2751 		} else {
2752 			(void)strlcpy(f->fu_fname, p, sizeof(f->fu_fname));
2753 			f->f_type = F_FILE;
2754 		}
2755 		break;
2756 
2757 	case '|':
2758 		f->fu_pipe_pid = 0;
2759 		(void)strlcpy(f->fu_pipe_pname, p + 1,
2760 		    sizeof(f->fu_pipe_pname));
2761 		f->f_type = F_PIPE;
2762 		break;
2763 
2764 	case '*':
2765 		f->f_type = F_WALL;
2766 		break;
2767 
2768 	default:
2769 		for (i = 0; i < MAXUNAMES && *p; i++) {
2770 			for (q = p; *q && *q != ','; )
2771 				q++;
2772 			(void)strncpy(f->fu_uname[i], p, MAXLOGNAME - 1);
2773 			if ((q - p) >= MAXLOGNAME)
2774 				f->fu_uname[i][MAXLOGNAME - 1] = '\0';
2775 			else
2776 				f->fu_uname[i][q - p] = '\0';
2777 			while (*q == ',' || *q == ' ')
2778 				q++;
2779 			p = q;
2780 		}
2781 		f->f_type = F_USERS;
2782 		break;
2783 	}
2784 	return (f);
2785 }
2786 
2787 
2788 /*
2789  *  Decode a symbolic name to a numeric value
2790  */
2791 static int
decode(const char * name,const CODE * codetab)2792 decode(const char *name, const CODE *codetab)
2793 {
2794 	const CODE *c;
2795 	char *p, buf[40];
2796 
2797 	if (isdigit(*name))
2798 		return (atoi(name));
2799 
2800 	for (p = buf; *name && p < &buf[sizeof(buf) - 1]; p++, name++) {
2801 		if (isupper(*name))
2802 			*p = tolower(*name);
2803 		else
2804 			*p = *name;
2805 	}
2806 	*p = '\0';
2807 	for (c = codetab; c->c_name; c++)
2808 		if (!strcmp(buf, c->c_name))
2809 			return (c->c_val);
2810 
2811 	return (-1);
2812 }
2813 
2814 static void
markit(void)2815 markit(void)
2816 {
2817 	struct filed *f;
2818 	struct deadq_entry *dq, *dq0;
2819 
2820 	now = time((time_t *)NULL);
2821 	MarkSeq += TIMERINTVL;
2822 	if (MarkSeq >= MarkInterval) {
2823 		logmsg(LOG_INFO, NULL, LocalHostName, NULL, NULL, NULL, NULL,
2824 		    "-- MARK --", MARK);
2825 		MarkSeq = 0;
2826 	}
2827 
2828 	STAILQ_FOREACH(f, &fhead, next) {
2829 		if (f->f_prevcount && now >= REPEATTIME(f)) {
2830 			dprintf("flush %s: repeated %d times, %d sec.\n",
2831 			    TypeNames[f->f_type], f->f_prevcount,
2832 			    repeatinterval[f->f_repeatcount]);
2833 			fprintlog_successive(f, 0);
2834 			BACKOFF(f);
2835 		}
2836 	}
2837 
2838 	/* Walk the dead queue, and see if we should signal somebody. */
2839 	TAILQ_FOREACH_SAFE(dq, &deadq_head, dq_entries, dq0) {
2840 		switch (dq->dq_timeout) {
2841 		case 0:
2842 			/* Already signalled once, try harder now. */
2843 			if (kill(dq->dq_pid, SIGKILL) != 0)
2844 				(void)deadq_remove(dq);
2845 			break;
2846 
2847 		case 1:
2848 			/*
2849 			 * Timed out on dead queue, send terminate
2850 			 * signal.  Note that we leave the removal
2851 			 * from the dead queue to reapchild(), which
2852 			 * will also log the event (unless the process
2853 			 * didn't even really exist, in case we simply
2854 			 * drop it from the dead queue).
2855 			 */
2856 			if (kill(dq->dq_pid, SIGTERM) != 0)
2857 				(void)deadq_remove(dq);
2858 			else
2859 				dq->dq_timeout--;
2860 			break;
2861 		default:
2862 			dq->dq_timeout--;
2863 		}
2864 	}
2865 	MarkSet = 0;
2866 	(void)alarm(TIMERINTVL);
2867 }
2868 
2869 /*
2870  * fork off and become a daemon, but wait for the child to come online
2871  * before returning to the parent, or we get disk thrashing at boot etc.
2872  * Set a timer so we don't hang forever if it wedges.
2873  */
2874 static int
waitdaemon(int maxwait)2875 waitdaemon(int maxwait)
2876 {
2877 	int fd;
2878 	int status;
2879 	pid_t pid, childpid;
2880 
2881 	switch (childpid = fork()) {
2882 	case -1:
2883 		return (-1);
2884 	case 0:
2885 		break;
2886 	default:
2887 		signal(SIGALRM, timedout);
2888 		alarm(maxwait);
2889 		while ((pid = wait3(&status, 0, NULL)) != -1) {
2890 			if (WIFEXITED(status))
2891 				errx(1, "child pid %d exited with return code %d",
2892 					pid, WEXITSTATUS(status));
2893 			if (WIFSIGNALED(status))
2894 				errx(1, "child pid %d exited on signal %d%s",
2895 					pid, WTERMSIG(status),
2896 					WCOREDUMP(status) ? " (core dumped)" :
2897 					"");
2898 			if (pid == childpid)	/* it's gone... */
2899 				break;
2900 		}
2901 		exit(0);
2902 	}
2903 
2904 	if (setsid() == -1)
2905 		return (-1);
2906 
2907 	(void)chdir("/");
2908 	if ((fd = open(_PATH_DEVNULL, O_RDWR, 0)) != -1) {
2909 		(void)dup2(fd, STDIN_FILENO);
2910 		(void)dup2(fd, STDOUT_FILENO);
2911 		(void)dup2(fd, STDERR_FILENO);
2912 		if (fd > STDERR_FILENO)
2913 			(void)close(fd);
2914 	}
2915 	return (getppid());
2916 }
2917 
2918 /*
2919  * We get a SIGALRM from the child when it's running and finished doing it's
2920  * fsync()'s or O_SYNC writes for all the boot messages.
2921  *
2922  * We also get a signal from the kernel if the timer expires, so check to
2923  * see what happened.
2924  */
2925 static void
timedout(int sig __unused)2926 timedout(int sig __unused)
2927 {
2928 	int left;
2929 	left = alarm(0);
2930 	signal(SIGALRM, SIG_DFL);
2931 	if (left == 0)
2932 		errx(1, "timed out waiting for child");
2933 	else
2934 		_exit(0);
2935 }
2936 
2937 /*
2938  * Add `s' to the list of allowable peer addresses to accept messages
2939  * from.
2940  *
2941  * `s' is a string in the form:
2942  *
2943  *    [*]domainname[:{servicename|portnumber|*}]
2944  *
2945  * or
2946  *
2947  *    netaddr/maskbits[:{servicename|portnumber|*}]
2948  *
2949  * Returns -1 on error, 0 if the argument was valid.
2950  */
2951 static int
2952 #if defined(INET) || defined(INET6)
allowaddr(char * s)2953 allowaddr(char *s)
2954 #else
2955 allowaddr(char *s __unused)
2956 #endif
2957 {
2958 #if defined(INET) || defined(INET6)
2959 	char *cp1, *cp2;
2960 	struct allowedpeer *ap;
2961 	struct servent *se;
2962 	int masklen = -1;
2963 	struct addrinfo hints, *res = NULL;
2964 #ifdef INET
2965 	in_addr_t *addrp, *maskp;
2966 #endif
2967 #ifdef INET6
2968 	uint32_t *addr6p, *mask6p;
2969 #endif
2970 	char ip[NI_MAXHOST];
2971 
2972 	ap = calloc(1, sizeof(*ap));
2973 	if (ap == NULL)
2974 		err(1, "malloc failed");
2975 
2976 #ifdef INET6
2977 	if (*s != '[' || (cp1 = strchr(s + 1, ']')) == NULL)
2978 #endif
2979 		cp1 = s;
2980 	if ((cp1 = strrchr(cp1, ':'))) {
2981 		/* service/port provided */
2982 		*cp1++ = '\0';
2983 		if (strlen(cp1) == 1 && *cp1 == '*')
2984 			/* any port allowed */
2985 			ap->port = 0;
2986 		else if ((se = getservbyname(cp1, "udp"))) {
2987 			ap->port = ntohs(se->s_port);
2988 		} else {
2989 			ap->port = strtol(cp1, &cp2, 0);
2990 			/* port not numeric */
2991 			if (*cp2 != '\0')
2992 				goto err;
2993 		}
2994 	} else {
2995 		if ((se = getservbyname("syslog", "udp")))
2996 			ap->port = ntohs(se->s_port);
2997 		else
2998 			/* sanity, should not happen */
2999 			ap->port = 514;
3000 	}
3001 
3002 	if ((cp1 = strchr(s, '/')) != NULL &&
3003 	    strspn(cp1 + 1, "0123456789") == strlen(cp1 + 1)) {
3004 		*cp1 = '\0';
3005 		if ((masklen = atoi(cp1 + 1)) < 0)
3006 			goto err;
3007 	}
3008 #ifdef INET6
3009 	if (*s == '[') {
3010 		cp2 = s + strlen(s) - 1;
3011 		if (*cp2 == ']') {
3012 			++s;
3013 			*cp2 = '\0';
3014 		} else {
3015 			cp2 = NULL;
3016 		}
3017 	} else {
3018 		cp2 = NULL;
3019 	}
3020 #endif
3021 	hints = (struct addrinfo){
3022 		.ai_family = PF_UNSPEC,
3023 		.ai_socktype = SOCK_DGRAM,
3024 		.ai_flags = AI_PASSIVE | AI_NUMERICHOST
3025 	};
3026 	if (getaddrinfo(s, NULL, &hints, &res) == 0) {
3027 		ap->isnumeric = 1;
3028 		memcpy(&ap->a_addr, res->ai_addr, res->ai_addrlen);
3029 		ap->a_mask = (struct sockaddr_storage){
3030 			.ss_family = res->ai_family,
3031 			.ss_len = res->ai_addrlen
3032 		};
3033 		switch (res->ai_family) {
3034 #ifdef INET
3035 		case AF_INET:
3036 			maskp = &sstosin(&ap->a_mask)->sin_addr.s_addr;
3037 			addrp = &sstosin(&ap->a_addr)->sin_addr.s_addr;
3038 			if (masklen < 0) {
3039 				/* use default netmask */
3040 				if (IN_CLASSA(ntohl(*addrp)))
3041 					*maskp = htonl(IN_CLASSA_NET);
3042 				else if (IN_CLASSB(ntohl(*addrp)))
3043 					*maskp = htonl(IN_CLASSB_NET);
3044 				else
3045 					*maskp = htonl(IN_CLASSC_NET);
3046 			} else if (masklen == 0) {
3047 				*maskp = 0;
3048 			} else if (masklen <= 32) {
3049 				/* convert masklen to netmask */
3050 				*maskp = htonl(~((1 << (32 - masklen)) - 1));
3051 			} else {
3052 				goto err;
3053 			}
3054 			/* Lose any host bits in the network number. */
3055 			*addrp &= *maskp;
3056 			break;
3057 #endif
3058 #ifdef INET6
3059 		case AF_INET6:
3060 			if (masklen > 128)
3061 				goto err;
3062 
3063 			if (masklen < 0)
3064 				masklen = 128;
3065 			mask6p = (uint32_t *)&sstosin6(&ap->a_mask)->sin6_addr.s6_addr32[0];
3066 			addr6p = (uint32_t *)&sstosin6(&ap->a_addr)->sin6_addr.s6_addr32[0];
3067 			/* convert masklen to netmask */
3068 			while (masklen > 0) {
3069 				if (masklen < 32) {
3070 					*mask6p =
3071 					    htonl(~(0xffffffff >> masklen));
3072 					*addr6p &= *mask6p;
3073 					break;
3074 				} else {
3075 					*mask6p++ = 0xffffffff;
3076 					addr6p++;
3077 					masklen -= 32;
3078 				}
3079 			}
3080 			break;
3081 #endif
3082 		default:
3083 			goto err;
3084 		}
3085 		freeaddrinfo(res);
3086 	} else {
3087 		/* arg `s' is domain name */
3088 		ap->isnumeric = 0;
3089 		ap->a_name = s;
3090 		if (cp1)
3091 			*cp1 = '/';
3092 #ifdef INET6
3093 		if (cp2) {
3094 			*cp2 = ']';
3095 			--s;
3096 		}
3097 #endif
3098 	}
3099 	STAILQ_INSERT_TAIL(&aphead, ap, next);
3100 
3101 	if (Debug) {
3102 		printf("allowaddr: rule ");
3103 		if (ap->isnumeric) {
3104 			printf("numeric, ");
3105 			getnameinfo(sstosa(&ap->a_addr),
3106 				    (sstosa(&ap->a_addr))->sa_len,
3107 				    ip, sizeof ip, NULL, 0, NI_NUMERICHOST);
3108 			printf("addr = %s, ", ip);
3109 			getnameinfo(sstosa(&ap->a_mask),
3110 				    (sstosa(&ap->a_mask))->sa_len,
3111 				    ip, sizeof ip, NULL, 0, NI_NUMERICHOST);
3112 			printf("mask = %s; ", ip);
3113 		} else {
3114 			printf("domainname = %s; ", ap->a_name);
3115 		}
3116 		printf("port = %d\n", ap->port);
3117 	}
3118 
3119 	return (0);
3120 err:
3121 	if (res != NULL)
3122 		freeaddrinfo(res);
3123 	free(ap);
3124 #endif
3125 	return (-1);
3126 }
3127 
3128 /*
3129  * Validate that the remote peer has permission to log to us.
3130  */
3131 static int
validate(struct sockaddr * sa,const char * hname)3132 validate(struct sockaddr *sa, const char *hname)
3133 {
3134 	int i;
3135 	char name[NI_MAXHOST], ip[NI_MAXHOST], port[NI_MAXSERV];
3136 	struct allowedpeer *ap;
3137 #ifdef INET
3138 	struct sockaddr_in *sin4, *a4p = NULL, *m4p = NULL;
3139 #endif
3140 #ifdef INET6
3141 	struct sockaddr_in6 *sin6, *a6p = NULL, *m6p = NULL;
3142 #endif
3143 	struct addrinfo hints, *res;
3144 	u_short sport;
3145 	int num = 0;
3146 
3147 	STAILQ_FOREACH(ap, &aphead, next) {
3148 		num++;
3149 	}
3150 	dprintf("# of validation rule: %d\n", num);
3151 	if (num == 0)
3152 		/* traditional behaviour, allow everything */
3153 		return (1);
3154 
3155 	(void)strlcpy(name, hname, sizeof(name));
3156 	hints = (struct addrinfo){
3157 		.ai_family = PF_UNSPEC,
3158 		.ai_socktype = SOCK_DGRAM,
3159 		.ai_flags = AI_PASSIVE | AI_NUMERICHOST
3160 	};
3161 	if (getaddrinfo(name, NULL, &hints, &res) == 0)
3162 		freeaddrinfo(res);
3163 	else if (strchr(name, '.') == NULL) {
3164 		strlcat(name, ".", sizeof name);
3165 		strlcat(name, LocalDomain, sizeof name);
3166 	}
3167 	if (getnameinfo(sa, sa->sa_len, ip, sizeof(ip), port, sizeof(port),
3168 			NI_NUMERICHOST | NI_NUMERICSERV) != 0)
3169 		return (0);	/* for safety, should not occur */
3170 	dprintf("validate: dgram from IP %s, port %s, name %s;\n",
3171 		ip, port, name);
3172 	sport = atoi(port);
3173 
3174 	/* now, walk down the list */
3175 	i = 0;
3176 	STAILQ_FOREACH(ap, &aphead, next) {
3177 		i++;
3178 		if (ap->port != 0 && ap->port != sport) {
3179 			dprintf("rejected in rule %d due to port mismatch.\n",
3180 			    i);
3181 			continue;
3182 		}
3183 
3184 		if (ap->isnumeric) {
3185 			if (ap->a_addr.ss_family != sa->sa_family) {
3186 				dprintf("rejected in rule %d due to address family mismatch.\n", i);
3187 				continue;
3188 			}
3189 #ifdef INET
3190 			else if (ap->a_addr.ss_family == AF_INET) {
3191 				sin4 = satosin(sa);
3192 				a4p = satosin(&ap->a_addr);
3193 				m4p = satosin(&ap->a_mask);
3194 				if ((sin4->sin_addr.s_addr & m4p->sin_addr.s_addr)
3195 				    != a4p->sin_addr.s_addr) {
3196 					dprintf("rejected in rule %d due to IP mismatch.\n", i);
3197 					continue;
3198 				}
3199 			}
3200 #endif
3201 #ifdef INET6
3202 			else if (ap->a_addr.ss_family == AF_INET6) {
3203 				sin6 = satosin6(sa);
3204 				a6p = satosin6(&ap->a_addr);
3205 				m6p = satosin6(&ap->a_mask);
3206 				if (a6p->sin6_scope_id != 0 &&
3207 				    sin6->sin6_scope_id != a6p->sin6_scope_id) {
3208 					dprintf("rejected in rule %d due to scope mismatch.\n", i);
3209 					continue;
3210 				}
3211 				if (!IN6_ARE_MASKED_ADDR_EQUAL(&sin6->sin6_addr,
3212 				    &a6p->sin6_addr, &m6p->sin6_addr)) {
3213 					dprintf("rejected in rule %d due to IP mismatch.\n", i);
3214 					continue;
3215 				}
3216 			}
3217 #endif
3218 			else
3219 				continue;
3220 		} else {
3221 			if (fnmatch(ap->a_name, name, FNM_NOESCAPE) ==
3222 			    FNM_NOMATCH) {
3223 				dprintf("rejected in rule %d due to name "
3224 				    "mismatch.\n", i);
3225 				continue;
3226 			}
3227 		}
3228 		dprintf("accepted in rule %d.\n", i);
3229 		return (1);	/* hooray! */
3230 	}
3231 	return (0);
3232 }
3233 
3234 /*
3235  * Fairly similar to popen(3), but returns an open descriptor, as
3236  * opposed to a FILE *.
3237  */
3238 static int
p_open(const char * prog,pid_t * rpid)3239 p_open(const char *prog, pid_t *rpid)
3240 {
3241 	int pfd[2], nulldesc;
3242 	pid_t pid;
3243 	char *argv[4]; /* sh -c cmd NULL */
3244 	char errmsg[200];
3245 
3246 	if (pipe(pfd) == -1)
3247 		return (-1);
3248 	if ((nulldesc = open(_PATH_DEVNULL, O_RDWR)) == -1)
3249 		/* we are royally screwed anyway */
3250 		return (-1);
3251 
3252 	switch ((pid = fork())) {
3253 	case -1:
3254 		close(nulldesc);
3255 		return (-1);
3256 
3257 	case 0:
3258 		(void)setsid();	/* Avoid catching SIGHUPs. */
3259 		argv[0] = strdup("sh");
3260 		argv[1] = strdup("-c");
3261 		argv[2] = strdup(prog);
3262 		argv[3] = NULL;
3263 		if (argv[0] == NULL || argv[1] == NULL || argv[2] == NULL) {
3264 			logerror("strdup");
3265 			exit(1);
3266 		}
3267 
3268 		alarm(0);
3269 
3270 		/* Restore signals marked as SIG_IGN. */
3271 		(void)signal(SIGINT, SIG_DFL);
3272 		(void)signal(SIGQUIT, SIG_DFL);
3273 		(void)signal(SIGPIPE, SIG_DFL);
3274 
3275 		dup2(pfd[0], STDIN_FILENO);
3276 		dup2(nulldesc, STDOUT_FILENO);
3277 		dup2(nulldesc, STDERR_FILENO);
3278 		closefrom(STDERR_FILENO + 1);
3279 
3280 		(void)execvp(_PATH_BSHELL, argv);
3281 		_exit(255);
3282 	}
3283 	close(nulldesc);
3284 	close(pfd[0]);
3285 	/*
3286 	 * Avoid blocking on a hung pipe.  With O_NONBLOCK, we are
3287 	 * supposed to get an EWOULDBLOCK on writev(2), which is
3288 	 * caught by the logic above anyway, which will in turn close
3289 	 * the pipe, and fork a new logging subprocess if necessary.
3290 	 * The stale subprocess will be killed some time later unless
3291 	 * it terminated itself due to closing its input pipe (so we
3292 	 * get rid of really dead puppies).
3293 	 */
3294 	if (fcntl(pfd[1], F_SETFL, O_NONBLOCK) == -1) {
3295 		/* This is bad. */
3296 		(void)snprintf(errmsg, sizeof errmsg,
3297 			       "Warning: cannot change pipe to PID %d to "
3298 			       "non-blocking behaviour.",
3299 			       (int)pid);
3300 		logerror(errmsg);
3301 	}
3302 	*rpid = pid;
3303 	return (pfd[1]);
3304 }
3305 
3306 static void
deadq_enter(pid_t pid,const char * name)3307 deadq_enter(pid_t pid, const char *name)
3308 {
3309 	struct deadq_entry *dq;
3310 	int status;
3311 
3312 	if (pid == 0)
3313 		return;
3314 	/*
3315 	 * Be paranoid, if we can't signal the process, don't enter it
3316 	 * into the dead queue (perhaps it's already dead).  If possible,
3317 	 * we try to fetch and log the child's status.
3318 	 */
3319 	if (kill(pid, 0) != 0) {
3320 		if (waitpid(pid, &status, WNOHANG) > 0)
3321 			log_deadchild(pid, status, name);
3322 		return;
3323 	}
3324 
3325 	dq = malloc(sizeof(*dq));
3326 	if (dq == NULL) {
3327 		logerror("malloc");
3328 		exit(1);
3329 	}
3330 	*dq = (struct deadq_entry){
3331 		.dq_pid = pid,
3332 		.dq_timeout = DQ_TIMO_INIT
3333 	};
3334 	TAILQ_INSERT_TAIL(&deadq_head, dq, dq_entries);
3335 }
3336 
3337 static int
deadq_remove(struct deadq_entry * dq)3338 deadq_remove(struct deadq_entry *dq)
3339 {
3340 	if (dq != NULL) {
3341 		TAILQ_REMOVE(&deadq_head, dq, dq_entries);
3342 		free(dq);
3343 		return (1);
3344 	}
3345 
3346 	return (0);
3347 }
3348 
3349 static int
deadq_removebypid(pid_t pid)3350 deadq_removebypid(pid_t pid)
3351 {
3352 	struct deadq_entry *dq;
3353 
3354 	TAILQ_FOREACH(dq, &deadq_head, dq_entries) {
3355 		if (dq->dq_pid == pid)
3356 			break;
3357 	}
3358 	return (deadq_remove(dq));
3359 }
3360 
3361 static void
log_deadchild(pid_t pid,int status,const char * name)3362 log_deadchild(pid_t pid, int status, const char *name)
3363 {
3364 	int code;
3365 	char buf[256];
3366 	const char *reason;
3367 
3368 	errno = 0; /* Keep strerror() stuff out of logerror messages. */
3369 	if (WIFSIGNALED(status)) {
3370 		reason = "due to signal";
3371 		code = WTERMSIG(status);
3372 	} else {
3373 		reason = "with status";
3374 		code = WEXITSTATUS(status);
3375 		if (code == 0)
3376 			return;
3377 	}
3378 	(void)snprintf(buf, sizeof buf,
3379 		       "Logging subprocess %d (%s) exited %s %d.",
3380 		       pid, name, reason, code);
3381 	logerror(buf);
3382 }
3383 
3384 static int
socksetup(struct peer * pe)3385 socksetup(struct peer *pe)
3386 {
3387 	struct addrinfo hints, *res, *res0;
3388 	int error;
3389 	char *cp;
3390 	int (*sl_recv)(struct socklist *);
3391 	/*
3392 	 * We have to handle this case for backwards compatibility:
3393 	 * If there are two (or more) colons but no '[' and ']',
3394 	 * assume this is an inet6 address without a service.
3395 	 */
3396 	if (pe->pe_name != NULL) {
3397 #ifdef INET6
3398 		if (pe->pe_name[0] == '[' &&
3399 		    (cp = strchr(pe->pe_name + 1, ']')) != NULL) {
3400 			pe->pe_name = &pe->pe_name[1];
3401 			*cp = '\0';
3402 			if (cp[1] == ':' && cp[2] != '\0')
3403 				pe->pe_serv = cp + 2;
3404 		} else {
3405 #endif
3406 			cp = strchr(pe->pe_name, ':');
3407 			if (cp != NULL && strchr(cp + 1, ':') == NULL) {
3408 				*cp = '\0';
3409 				if (cp[1] != '\0')
3410 					pe->pe_serv = cp + 1;
3411 				if (cp == pe->pe_name)
3412 					pe->pe_name = NULL;
3413 			}
3414 #ifdef INET6
3415 		}
3416 #endif
3417 	}
3418 	hints = (struct addrinfo){
3419 		.ai_family = AF_UNSPEC,
3420 		.ai_socktype = SOCK_DGRAM,
3421 		.ai_flags = AI_PASSIVE
3422 	};
3423 	if (pe->pe_name != NULL)
3424 		dprintf("Trying peer: %s\n", pe->pe_name);
3425 	if (pe->pe_serv == NULL)
3426 		pe->pe_serv = "syslog";
3427 	error = getaddrinfo(pe->pe_name, pe->pe_serv, &hints, &res0);
3428 	if (error) {
3429 		char *msgbuf;
3430 
3431 		asprintf(&msgbuf, "getaddrinfo failed for %s%s: %s",
3432 		    pe->pe_name == NULL ? "" : pe->pe_name, pe->pe_serv,
3433 		    gai_strerror(error));
3434 		errno = 0;
3435 		if (msgbuf == NULL)
3436 			logerror(gai_strerror(error));
3437 		else
3438 			logerror(msgbuf);
3439 		free(msgbuf);
3440 		die(0);
3441 	}
3442 	for (res = res0; res != NULL; res = res->ai_next) {
3443 		int s;
3444 
3445 		if (res->ai_family != AF_LOCAL &&
3446 		    SecureMode > 1) {
3447 			/* Only AF_LOCAL in secure mode. */
3448 			continue;
3449 		}
3450 		if (family != AF_UNSPEC &&
3451 		    res->ai_family != AF_LOCAL && res->ai_family != family)
3452 			continue;
3453 
3454 		s = socket(res->ai_family, res->ai_socktype,
3455 		    res->ai_protocol);
3456 		if (s < 0) {
3457 			logerror("socket");
3458 			error++;
3459 			continue;
3460 		}
3461 #ifdef INET6
3462 		if (res->ai_family == AF_INET6) {
3463 			if (setsockopt(s, IPPROTO_IPV6, IPV6_V6ONLY,
3464 			       &(int){1}, sizeof(int)) < 0) {
3465 				logerror("setsockopt(IPV6_V6ONLY)");
3466 				close(s);
3467 				error++;
3468 				continue;
3469 			}
3470 		}
3471 #endif
3472 		if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR,
3473 		    &(int){1}, sizeof(int)) < 0) {
3474 			logerror("setsockopt(SO_REUSEADDR)");
3475 			close(s);
3476 			error++;
3477 			continue;
3478 		}
3479 
3480 		/*
3481 		 * Bind INET and UNIX-domain sockets.
3482 		 *
3483 		 * A UNIX-domain socket is always bound to a pathname
3484 		 * regardless of -N flag.
3485 		 *
3486 		 * For INET sockets, RFC 3164 recommends that client
3487 		 * side message should come from the privileged syslogd port.
3488 		 *
3489 		 * If the system administrator chooses not to obey
3490 		 * this, we can skip the bind() step so that the
3491 		 * system will choose a port for us.
3492 		 */
3493 		if (res->ai_family == AF_LOCAL)
3494 			unlink(pe->pe_name);
3495 		if (res->ai_family == AF_LOCAL ||
3496 		    NoBind == 0 || pe->pe_name != NULL) {
3497 			if (bind(s, res->ai_addr, res->ai_addrlen) < 0) {
3498 				logerror("bind");
3499 				close(s);
3500 				error++;
3501 				continue;
3502 			}
3503 			if (res->ai_family == AF_LOCAL ||
3504 			    SecureMode == 0)
3505 				increase_rcvbuf(s);
3506 		}
3507 		if (res->ai_family == AF_LOCAL &&
3508 		    chmod(pe->pe_name, pe->pe_mode) < 0) {
3509 			dprintf("chmod %s: %s\n", pe->pe_name,
3510 			    strerror(errno));
3511 			close(s);
3512 			error++;
3513 			continue;
3514 		}
3515 		dprintf("new socket fd is %d\n", s);
3516 		if (res->ai_socktype != SOCK_DGRAM) {
3517 			listen(s, 5);
3518 		}
3519 		sl_recv = socklist_recv_sock;
3520 #if defined(INET) || defined(INET6)
3521 		if (SecureMode && (res->ai_family == AF_INET ||
3522 		    res->ai_family == AF_INET6)) {
3523 			dprintf("shutdown\n");
3524 			/* Forbid communication in secure mode. */
3525 			if (shutdown(s, SHUT_RD) < 0 &&
3526 			    errno != ENOTCONN) {
3527 				logerror("shutdown");
3528 				if (!Debug)
3529 					die(0);
3530 			}
3531 			sl_recv = NULL;
3532 		} else
3533 #endif
3534 			dprintf("listening on socket\n");
3535 		dprintf("sending on socket\n");
3536 		addsock(res->ai_addr, res->ai_addrlen,
3537 		    &(struct socklist){
3538 			.sl_socket = s,
3539 			.sl_peer = pe,
3540 			.sl_recv = sl_recv
3541 		});
3542 	}
3543 	freeaddrinfo(res0);
3544 
3545 	return(error);
3546 }
3547 
3548 static void
increase_rcvbuf(int fd)3549 increase_rcvbuf(int fd)
3550 {
3551 	socklen_t len;
3552 
3553 	if (getsockopt(fd, SOL_SOCKET, SO_RCVBUF, &len,
3554 	    &(socklen_t){sizeof(len)}) == 0) {
3555 		if (len < RCVBUF_MINSIZE) {
3556 			len = RCVBUF_MINSIZE;
3557 			setsockopt(fd, SOL_SOCKET, SO_RCVBUF, &len, sizeof(len));
3558 		}
3559 	}
3560 }
3561