xref: /netbsd-src/usr.sbin/syslogd/syslogd.h (revision b5677b36047b601b9addaaa494a58ceae82c2a6c)
1 /*	$NetBSD: syslogd.h,v 1.2 2008/11/07 07:36:38 minskim Exp $	*/
2 
3 /*-
4  * Copyright (c) 2008 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Martin Sch�tte.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *        This product includes software developed by the NetBSD
21  *        Foundation, Inc. and its contributors.
22  * 4. Neither the name of The NetBSD Foundation nor the names of its
23  *    contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36  * POSSIBILITY OF SUCH DAMAGE.
37  */
38 #ifndef SYSLOGD_H_
39 #define SYSLOGD_H_
40 /*
41  * hold common data structures and prototypes
42  * for syslogd.c and tls.c
43  *
44  */
45 
46 #include <sys/cdefs.h>
47 #define MAXLINE		1024		/* maximum line length */
48 #define MAXSVLINE	120		/* maximum saved line length */
49 #define DEFUPRI		(LOG_USER|LOG_NOTICE)
50 #define DEFSPRI		(LOG_KERN|LOG_NOTICE)
51 #define TIMERINTVL	30		/* interval for checking flush, mark */
52 #define TTYMSGTIME	1		/* timeout passed to ttymsg */
53 
54 #include <sys/param.h>
55 #include <sys/socket.h>
56 #include <sys/sysctl.h>
57 #include <sys/types.h>
58 #include <sys/un.h>
59 #include <sys/wait.h>
60 #include <sys/queue.h>
61 #include <netinet/in.h>
62 #include <sys/event.h>
63 #include <event.h>
64 
65 #include <assert.h>
66 #include <ctype.h>
67 #include <errno.h>
68 #include <fcntl.h>
69 #include <grp.h>
70 #include <locale.h>
71 #include <netdb.h>
72 #include <pwd.h>
73 #include <signal.h>
74 #include <stdarg.h>
75 #include <stdio.h>
76 #include <stdlib.h>
77 #include <string.h>
78 #include <unistd.h>
79 #include <stdbool.h>
80 #include <utmp.h>
81 #ifdef __NetBSD_Version__
82 #include <util.h>
83 #include "utmpentry.h"
84 #endif /* __NetBSD_Version__ */
85 #ifdef __FreeBSD_version
86 #include <libutil.h>
87 #include <sys/stat.h>
88 #include <sys/uio.h>
89 #include <limits.h>
90 #endif /* __FreeBSD_version */
91 
92 #ifndef DISABLE_TLS
93 #include <netinet/tcp.h>
94 #include <openssl/ssl.h>
95 #endif /* !DISABLE_TLS */
96 
97 #include <sys/stdint.h>
98 #include <sys/resource.h>
99 
100 /* additional queue macros copied from FreeBSD	*/
101 #ifndef SLIST_FOREACH_SAFE
102 #define SLIST_FOREACH_SAFE(var, head, field, tvar)	    \
103     for ((var) = SLIST_FIRST((head));		    \
104 	(var) && ((tvar) = SLIST_NEXT((var), field), 1);	\
105 	(var) = (tvar))
106 #endif /* !SLIST_FOREACH_SAFE */
107 #ifndef STAILQ_FOREACH_SAFE
108 #define STAILQ_FOREACH_SAFE(var, head, field, tvar)	    \
109     for ((var) = STAILQ_FIRST((head));		    \
110 	(var) && ((tvar) = STAILQ_NEXT((var), field), 1);	\
111 	(var) = (tvar))
112 #endif /* !STAILQ_FOREACH_SAFE */
113 #ifndef STAILQ_LAST
114 #define STAILQ_LAST(head, type, field)			\
115     (STAILQ_EMPTY((head)) ?			\
116 	NULL :				\
117 	    ((struct type *)			\
118 	((char *)((head)->stqh_last) - offsetof(struct type, field))))
119 #endif /* !STAILQ_LAST */
120 #ifndef STAILQ_CONCAT
121 #define STAILQ_CONCAT(head1, head2) do {	\
122   if (!STAILQ_EMPTY((head2))) {		\
123     *(head1)->stqh_last = (head2)->stqh_first;	  \
124     (head1)->stqh_last = (head2)->stqh_last;	\
125     STAILQ_INIT((head2));	  \
126   }		  \
127 } while (0)
128 #endif /* !STAILQ_CONCAT */
129 #ifndef TAILQ_CONCAT
130 #define TAILQ_CONCAT(head1, head2, field) do {		    \
131     if (!TAILQ_EMPTY(head2)) {			\
132 	*(head1)->tqh_last = (head2)->tqh_first;	\
133 	(head2)->tqh_first->field.tqe_prev = (head1)->tqh_last; \
134 	(head1)->tqh_last = (head2)->tqh_last;		\
135 	TAILQ_INIT((head2));			\
136     }				    \
137 } while (0)
138 #endif /* !TAILQ_CONCAT */
139 
140 #include "pathnames.h"
141 #include <sys/syslog.h>
142 
143 /* some differences between the BSDs  */
144 #ifdef __FreeBSD_version
145 #undef _PATH_UNIX
146 #define _PATH_UNIX "kernel"
147 #define HAVE_STRNDUP 0
148 #endif /* __FreeBSD_version */
149 
150 #ifdef __NetBSD_Version__
151 #define HAVE_STRNDUP 1
152 #define HAVE_DEHUMANIZE_NUMBER 1
153 #endif /* __NetBSD_Version__ */
154 
155 #ifndef HAVE_DEHUMANIZE_NUMBER	/* not in my 4.0-STABLE yet */
156 extern int dehumanize_number(const char *str, int64_t *size);
157 #endif /* !HAVE_DEHUMANIZE_NUMBER */
158 
159 #if !HAVE_STRNDUP
160 char *strndup(const char *str, size_t n);
161 #endif /* !HAVE_STRNDUP */
162 
163 #ifdef LIBWRAP
164 #include <tcpd.h>
165 #endif
166 
167 #define FDMASK(fd)	(1 << (fd))
168 
169 #define A_CNT(x)	(sizeof((x)) / sizeof((x)[0]))
170 
171 /* debug messages with categories */
172 #define D_NONE	   0
173 #define D_CALL	   1	/* function calls */
174 #define D_DATA	   2	/* syslog message reading/formatting */
175 #define D_NET	   4	/* sockets/network */
176 #define D_FILE	   8	/* local files */
177 #define D_TLS	  16	/* TLS */
178 #define D_PARSE	  32	/* configuration/parsing */
179 #define D_EVENT	  64	/* libevent */
180 #define D_BUFFER 128	/* message queues */
181 #define D_MEM	 256	/* malloc/free */
182 #define D_MEM2	1024	/* every single malloc/free */
183 #define D_SIGN	2048	/* -sign */
184 #define D_MISC	4096	/* everything else */
185 #define D_ALL	(D_CALL | D_DATA | D_NET | D_FILE | D_TLS | D_PARSE |  \
186 		 D_EVENT | D_BUFFER | D_MEM | D_MEM2 | D_SIGN | D_MISC)
187 #define D_DEFAULT (D_CALL | D_NET | D_FILE | D_TLS | D_MISC)
188 
189 
190 /* build with -DNDEBUG to remove all assert()s and DPRINTF()s */
191 #ifdef NDEBUG
192 #define DPRINTF(x, ...) (void)0
193 #else
194 #define DPRINTF(x, ...) /*LINTED null effect */(void)(Debug & (x) \
195     ? (printf("%s:%s:%s:%.4d\t", make_timestamp(NULL, true), \
196     __FILE__, __func__, __LINE__), printf(__VA_ARGS__)) : 0)
197 #endif
198 
199 /* shortcuts for libevent */
200 #define EVENT_ADD(x) do {						\
201 	DPRINTF(D_EVENT, "event_add(%s@%p)\n", #x, x);			\
202 	if (event_add(x, NULL) == -1) {					\
203 		DPRINTF(D_EVENT, "Failure in event_add()\n");		\
204 	}								\
205 } while (/*CONSTCOND*/0)
206 #define RETRYEVENT_ADD(x) do {						\
207 	struct timeval _tv;						\
208 	_tv.tv_sec = 0;							\
209 	_tv.tv_usec = TLS_RETRY_EVENT_USEC;				\
210 	DPRINTF(D_EVENT, "retryevent_add(%s@%p)\n", #x, x);		\
211 	if (event_add(x, &_tv) == -1) {					\
212 		DPRINTF(D_EVENT, "Failure in event_add()\n");		\
213 	}								\
214 } while (/*CONSTCOND*/0)
215 #define DEL_EVENT(x) do {						\
216 	DPRINTF(D_MEM2, "DEL_EVENT(%s@%p)\n", #x, x);			\
217 	if ((x) && (event_del(x) == -1)) {				\
218 		DPRINTF(D_EVENT, "Failure in event_del()\n");		\
219 	}								\
220 } while (/*CONSTCOND*/0)
221 
222 /* safe calls to free() */
223 #define FREEPTR(x)	if (x) {					\
224 		DPRINTF(D_MEM2, "free(%s@%p)\n", #x, x);		\
225 		free(x);	 x = NULL; }
226 #define FREE_SSL(x)	if (x) {					\
227 		DPRINTF(D_MEM2, "SSL_free(%s@%p)\n", #x, x);		\
228 		SSL_free(x);	 x = NULL; }
229 #define FREE_SSL_CTX(x) if (x) {					\
230 		DPRINTF(D_MEM2, "SSL_CTX_free(%s@%p)\n", #x, x);	\
231 		SSL_CTX_free(x); x = NULL; }
232 
233 /* reference counting macros for buffers */
234 #define NEWREF(x) ((x) ? (DPRINTF(D_BUFFER, "inc refcount of " #x \
235 			" @ %p: %zu --> %zu\n", (x), (x)->refcount, \
236 			(x)->refcount + 1), (x)->refcount++, (x))\
237 		       : (DPRINTF(D_BUFFER, "inc refcount of NULL!\n"), NULL))
238 #define DELREF(x) /*LINTED null effect*/(void)((x) ? (DPRINTF(D_BUFFER, "dec refcount of " #x \
239 			" @ %p: %zu --> %zu\n", (x), (x)->refcount, \
240 			(x)->refcount - 1), buf_msg_free(x), NULL) \
241 		       : (DPRINTF(D_BUFFER, "dec refcount of NULL!\n"), NULL))
242 
243 /* assumption:
244  * - malloc()/calloc() only fails if not enough memory available
245  * - once init() has set up all global variables etc.
246  *   the bulk of available memory is used for buffers
247  *   and can be freed if necessary
248  */
249 #define MALLOC(ptr, size) do {						\
250 	while(!(ptr = malloc(size))) {					\
251 		DPRINTF(D_MEM, "Unable to allocate memory");		\
252 		message_allqueues_purge();				\
253 	}								\
254 	DPRINTF(D_MEM2, "MALLOC(%s@%p, %zu)\n", #ptr, ptr, size);	\
255 } while (/*CONSTCOND*/0)
256 
257 #define CALLOC(ptr, size) do {						\
258 	while(!(ptr = calloc(1, size))) {				\
259 		DPRINTF(D_MEM, "Unable to allocate memory");		\
260 		message_allqueues_purge();				\
261 	}								\
262 	DPRINTF(D_MEM2, "CALLOC(%s@%p, %zu)\n", #ptr, ptr, size);	\
263 } while (/*CONSTCOND*/0)
264 
265 /* define strlen(NULL) to be 0 */
266 #define SAFEstrlen(x) ((x) ? strlen(x) : 0)
267 
268 /* shorthand to block/restore signals for the duration of one function */
269 #define BLOCK_SIGNALS(omask, newmask) do {				\
270 	sigemptyset(&newmask);						\
271 	sigaddset(&newmask, SIGHUP);					\
272 	sigaddset(&newmask, SIGALRM);					\
273 	sigprocmask(SIG_BLOCK, &newmask, &omask);			\
274 } while (/*CONSTCOND*/0)
275 
276 #define RESTORE_SIGNALS(omask) sigprocmask(SIG_SETMASK, &omask, NULL)
277 
278 /* small optimization to call send_queue() only if queue has elements */
279 #define SEND_QUEUE(f) do {						\
280 	if ((f)->f_qelements)						\
281 		send_queue(0, 0, f);	      				\
282 } while (/*CONSTCOND*/0)
283 
284 #define MAXUNAMES		20	/* maximum number of user names */
285 #define BSD_TIMESTAMPLEN	14+1
286 #define MAX_TIMESTAMPLEN	31+1
287 
288 /* maximum field lengths in syslog-protocol */
289 #define PRI_MAX	      5
290 #define HOST_MAX    255
291 #define APPNAME_MAX  48
292 #define PROCID_MAX  128
293 #define MSGID_MAX    32
294 /* longest possible header length */
295 #define HEADER_LEN_MAX (PRI_MAX + 1 + 1 + MAX_TIMESTAMPLEN + 1 + HOST_MAX \
296 			+ 1 + APPNAME_MAX + 1 + PROCID_MAX + 1 + MSGID_MAX)
297 
298 /* allowed number of priorities by IETF standards */
299 #define IETF_NUM_PRIVALUES  192
300 
301 /* check if message with fac/sev belogs to a destination f */
302 #define MATCH_PRI(f, fac, sev) \
303 	   (  (((f)->f_pcmp[fac] & PRI_EQ) && ((f)->f_pmask[fac] == (sev))) \
304 	    ||(((f)->f_pcmp[fac] & PRI_LT) && ((f)->f_pmask[fac]  < (sev)))  \
305 	    ||(((f)->f_pcmp[fac] & PRI_GT) && ((f)->f_pmask[fac]  > (sev)))  \
306 	   )
307 
308 /* shorthand to test Byte Order Mark which indicates UTF-8 content */
309 #define IS_BOM(p) ( \
310     (p)[0] != '\0' && (unsigned char)(p)[0] == (unsigned char)0xEF && \
311     (p)[1] != '\0' && (unsigned char)(p)[1] == (unsigned char)0xBB && \
312     (p)[2] != '\0' && (unsigned char)(p)[2] == (unsigned char)0xBF)
313 
314 /* message buffer container used for processing, formatting, and queueing */
315 struct buf_msg {
316 	size_t	 refcount;
317 	int	 pri;
318 	int	 flags;
319 	char	*timestamp;
320 	char	*recvhost;
321 	char	*host;
322 	char	*prog;
323 	char	*pid;
324 	char	*msgid;
325 	char	*sd;	    /* structured data */
326 	char	*msg;	    /* message content */
327 	char	*msgorig;   /* in case we advance *msg beyond header fields
328 			       we still want to free() the original ptr  */
329 	size_t	 msglen;    /* strlen(msg) */
330 	size_t	 msgsize;   /* allocated memory size   */
331 	size_t	 tlsprefixlen; /* bytes for the TLS length prefix */
332 	size_t	 prilen;       /* bytes for priority and version  */
333 };
334 
335 /* queue of messages */
336 struct buf_queue {
337 	struct buf_msg* msg;
338 	STAILQ_ENTRY(buf_queue) entries;
339 };
340 STAILQ_HEAD(buf_queue_head, buf_queue);
341 
342 /* a pair of a socket and an associated event object */
343 struct socketEvent {
344 	int fd;
345 	struct event *ev;
346 };
347 
348 /*
349  * Flags to logmsg().
350  */
351 #define IGN_CONS	0x001	/* don't print on console */
352 #define SYNC_FILE	0x002	/* do fsync on file after printing */
353 #define ADDDATE		0x004	/* add a date to the message */
354 #define MARK		0x008	/* this message is a mark */
355 #define ISKERNEL	0x010	/* kernel generated message */
356 #define BSDSYSLOG	0x020	/* line in traditional BSD Syslog format */
357 #define SIGN_MSG	0x040	/* syslog-sign data, not signed again */
358 
359 /* strategies for message_queue_purge() */
360 #define PURGE_OLDEST		1
361 #define PURGE_BY_PRIORITY	2
362 
363 /*
364  * This structure represents the files that will have log
365  * copies printed.
366  * We require f_file to be valid if f_type is F_FILE, F_CONSOLE, F_TTY,
367  * or if f_type is F_PIPE and f_pid > 0.
368  */
369 
370 struct filed {
371 	struct	filed *f_next;		/* next in linked list */
372 	short	f_type;			/* entry type, see below */
373 	short	f_file;			/* file descriptor */
374 	time_t	f_time;			/* time this was last written */
375 	char	*f_host;		/* host from which to record */
376 	u_char	f_pmask[LOG_NFACILITIES+1];	/* priority mask */
377 	u_char	f_pcmp[LOG_NFACILITIES+1];	/* compare priority */
378 #define PRI_LT	0x1
379 #define PRI_EQ	0x2
380 #define PRI_GT	0x4
381 	char	*f_program;		/* program this applies to */
382 	union {
383 		char	f_uname[MAXUNAMES][UT_NAMESIZE+1];
384 		struct {
385 			char	f_hname[MAXHOSTNAMELEN];
386 			struct	addrinfo *f_addr;
387 		} f_forw;		/* UDP forwarding address */
388 #ifndef DISABLE_TLS
389 		struct {
390 			SSL	*ssl;			/* SSL object  */
391 			struct tls_conn_settings *tls_conn;  /* certificate info */
392 		} f_tls;		/* TLS forwarding address */
393 #endif /* !DISABLE_TLS */
394 		char	f_fname[MAXPATHLEN];
395 		struct {
396 			char	f_pname[MAXPATHLEN];
397 			pid_t	f_pid;
398 		} f_pipe;
399 	} f_un;
400 #ifndef DISABLE_SIGN
401 	struct signature_group_t *f_sg;	     /* one signature group */
402 #endif /* !DISABLE_SIGN */
403 	struct buf_queue_head f_qhead;	     /* undelivered msgs queue */
404 	size_t	      	      f_qelements;   /* elements in queue */
405 	size_t		      f_qsize;	     /* size of queue in bytes */
406 	struct buf_msg	     *f_prevmsg;     /* last message logged */
407 	struct event	     *f_sq_event;    /* timer for send_queue() */
408 	int		      f_prevcount;   /* repetition cnt of prevmsg */
409 	int		      f_repeatcount; /* number of "repeated" msgs */
410 	int		      f_lasterror;   /* last error on writev() */
411 	int		      f_flags;	     /* file-specific flags */
412 #define FFLAG_SYNC	0x01	/* for F_FILE: fsync after every msg */
413 #define FFLAG_FULL	0x02	/* for F_FILE | F_PIPE: write PRI header */
414 #define FFLAG_SIGN	0x04	/* for syslog-sign with SG="3":
415 				 * sign the messages to this destination */
416 };
417 
418 #ifndef DISABLE_TLS
419 
420 /* linked list for allowed TLS peer credentials
421  * (one for fingerprint, one for cert-files)
422  */
423 SLIST_HEAD(peer_cred_head, peer_cred);
424 struct peer_cred {
425 	SLIST_ENTRY(peer_cred) entries;
426 	char *data;
427 };
428 
429 /* config options for TLS server-side */
430 struct tls_global_options_t {
431 	SSL_CTX *global_TLS_CTX;
432 	struct peer_cred_head fprint_head;  /* trusted client fingerprints */
433 	struct peer_cred_head cert_head;    /* trusted client cert files   */
434 	char *keyfile;	    /* file with private key	 */
435 	char *certfile;	    /* file with own certificate */
436 	char *CAfile;	    /* file with CA certificate	 */
437 	char *CAdir;	    /* alternative: path to directory with CA certs */
438 	char *x509verify;   /* level of peer verification */
439 	char *bindhost;	    /* hostname/IP to bind to	  */
440 	char *bindport;	    /* port/service to bind to	  */
441 	char *server;	    /* if !NULL: do not listen to incoming TLS	  */
442 	char *gen_cert;	    /* if !NULL: generate self-signed certificate */
443 };
444 
445 /* TLS needs three sets of sockets:
446  * - listening sockets: a fixed size array TLS_Listen_Set, just like finet for UDP.
447  * - outgoing connections: managed as part of struct filed.
448  * - incoming connections: variable sized, thus a linked list TLS_Incoming.
449  */
450 /* every connection has its own input buffer with status
451  * variables for message reading */
452 SLIST_HEAD(TLS_Incoming, TLS_Incoming_Conn);
453 
454 struct TLS_Incoming_Conn {
455 	SLIST_ENTRY(TLS_Incoming_Conn) entries;
456 	struct tls_conn_settings *tls_conn;
457 	int socket;
458 	char *inbuf;		    /* input buffer */
459 	size_t inbuflen;
460 	size_t cur_msg_len;	    /* length of current msg */
461 	size_t cur_msg_start;	    /* beginning of current msg */
462 	size_t read_pos;	    /* ring buffer position to write to */
463 	size_t errorcount;	    /* to close faulty connections */
464 	bool closenow;		    /* close connection as soon as buffer processed */
465 	bool dontsave;		    /* for receiving oversized messages w/o saving them */
466 };
467 
468 #endif /* !DISABLE_TLS */
469 
470 #endif /*SYSLOGD_H_*/
471