log.c revision 1.21 
1/*
2 * Author: Tatu Ylonen <ylo@cs.hut.fi>
3 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
4 *                    All rights reserved
5 *
6 * As far as I am concerned, the code I have written for this software
7 * can be used freely for any purpose.  Any derived versions of this
8 * software must be clearly marked as such, and if the derived work is
9 * incompatible with the protocol description in the RFC file, it must be
10 * called by a name other than "ssh" or "Secure Shell".
11 */
12/*
13 * Copyright (c) 2000 Markus Friedl.  All rights reserved.
14 *
15 * Redistribution and use in source and binary forms, with or without
16 * modification, are permitted provided that the following conditions
17 * are met:
18 * 1. Redistributions of source code must retain the above copyright
19 *    notice, this list of conditions and the following disclaimer.
20 * 2. Redistributions in binary form must reproduce the above copyright
21 *    notice, this list of conditions and the following disclaimer in the
22 *    documentation and/or other materials provided with the distribution.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
25 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
26 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
27 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
28 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
29 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
30 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
31 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
32 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
33 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
34 */
35
36#include "includes.h"
37RCSID("$OpenBSD: log.c,v 1.21 2002/02/04 12:15:25 markus Exp $");
38
39#include "log.h"
40#include "xmalloc.h"
41
42#include <syslog.h>
43
44static LogLevel log_level = SYSLOG_LEVEL_INFO;
45static int log_on_stderr = 1;
46static int log_facility = LOG_AUTH;
47static char *argv0;
48
49extern char *__progname;
50
51/* textual representation of log-facilities/levels */
52
53static struct {
54	const char *name;
55	SyslogFacility val;
56} log_facilities[] = {
57	{ "DAEMON",	SYSLOG_FACILITY_DAEMON },
58	{ "USER",	SYSLOG_FACILITY_USER },
59	{ "AUTH",	SYSLOG_FACILITY_AUTH },
60	{ "LOCAL0",	SYSLOG_FACILITY_LOCAL0 },
61	{ "LOCAL1",	SYSLOG_FACILITY_LOCAL1 },
62	{ "LOCAL2",	SYSLOG_FACILITY_LOCAL2 },
63	{ "LOCAL3",	SYSLOG_FACILITY_LOCAL3 },
64	{ "LOCAL4",	SYSLOG_FACILITY_LOCAL4 },
65	{ "LOCAL5",	SYSLOG_FACILITY_LOCAL5 },
66	{ "LOCAL6",	SYSLOG_FACILITY_LOCAL6 },
67	{ "LOCAL7",	SYSLOG_FACILITY_LOCAL7 },
68	{ NULL,		SYSLOG_FACILITY_NOT_SET }
69};
70
71static struct {
72	const char *name;
73	LogLevel val;
74} log_levels[] =
75{
76	{ "QUIET",	SYSLOG_LEVEL_QUIET },
77	{ "FATAL",	SYSLOG_LEVEL_FATAL },
78	{ "ERROR",	SYSLOG_LEVEL_ERROR },
79	{ "INFO",	SYSLOG_LEVEL_INFO },
80	{ "VERBOSE",	SYSLOG_LEVEL_VERBOSE },
81	{ "DEBUG",	SYSLOG_LEVEL_DEBUG1 },
82	{ "DEBUG1",	SYSLOG_LEVEL_DEBUG1 },
83	{ "DEBUG2",	SYSLOG_LEVEL_DEBUG2 },
84	{ "DEBUG3",	SYSLOG_LEVEL_DEBUG3 },
85	{ NULL,		SYSLOG_LEVEL_NOT_SET }
86};
87
88static void	 do_log(LogLevel level, const char *fmt, va_list args);
89
90SyslogFacility
91log_facility_number(char *name)
92{
93	int i;
94	if (name != NULL)
95		for (i = 0; log_facilities[i].name; i++)
96			if (strcasecmp(log_facilities[i].name, name) == 0)
97				return log_facilities[i].val;
98	return SYSLOG_FACILITY_NOT_SET;
99}
100
101LogLevel
102log_level_number(char *name)
103{
104	int i;
105	if (name != NULL)
106		for (i = 0; log_levels[i].name; i++)
107			if (strcasecmp(log_levels[i].name, name) == 0)
108				return log_levels[i].val;
109	return SYSLOG_LEVEL_NOT_SET;
110}
111/* Fatal messages.  This function never returns. */
112
113void
114fatal(const char *fmt,...)
115{
116	va_list args;
117	va_start(args, fmt);
118	do_log(SYSLOG_LEVEL_FATAL, fmt, args);
119	va_end(args);
120	fatal_cleanup();
121}
122
123/* Error messages that should be logged. */
124
125void
126error(const char *fmt,...)
127{
128	va_list args;
129	va_start(args, fmt);
130	do_log(SYSLOG_LEVEL_ERROR, fmt, args);
131	va_end(args);
132}
133
134/* Log this message (information that usually should go to the log). */
135
136void
137log(const char *fmt,...)
138{
139	va_list args;
140	va_start(args, fmt);
141	do_log(SYSLOG_LEVEL_INFO, fmt, args);
142	va_end(args);
143}
144
145/* More detailed messages (information that does not need to go to the log). */
146
147void
148verbose(const char *fmt,...)
149{
150	va_list args;
151	va_start(args, fmt);
152	do_log(SYSLOG_LEVEL_VERBOSE, fmt, args);
153	va_end(args);
154}
155
156/* Debugging messages that should not be logged during normal operation. */
157
158void
159debug(const char *fmt,...)
160{
161	va_list args;
162	va_start(args, fmt);
163	do_log(SYSLOG_LEVEL_DEBUG1, fmt, args);
164	va_end(args);
165}
166
167void
168debug2(const char *fmt,...)
169{
170	va_list args;
171	va_start(args, fmt);
172	do_log(SYSLOG_LEVEL_DEBUG2, fmt, args);
173	va_end(args);
174}
175
176void
177debug3(const char *fmt,...)
178{
179	va_list args;
180	va_start(args, fmt);
181	do_log(SYSLOG_LEVEL_DEBUG3, fmt, args);
182	va_end(args);
183}
184
185/* Fatal cleanup */
186
187struct fatal_cleanup {
188	struct fatal_cleanup *next;
189	void (*proc) (void *);
190	void *context;
191};
192
193static struct fatal_cleanup *fatal_cleanups = NULL;
194
195/* Registers a cleanup function to be called by fatal() before exiting. */
196
197void
198fatal_add_cleanup(void (*proc) (void *), void *context)
199{
200	struct fatal_cleanup *cu;
201
202	cu = xmalloc(sizeof(*cu));
203	cu->proc = proc;
204	cu->context = context;
205	cu->next = fatal_cleanups;
206	fatal_cleanups = cu;
207}
208
209/* Removes a cleanup frunction to be called at fatal(). */
210
211void
212fatal_remove_cleanup(void (*proc) (void *context), void *context)
213{
214	struct fatal_cleanup **cup, *cu;
215
216	for (cup = &fatal_cleanups; *cup; cup = &cu->next) {
217		cu = *cup;
218		if (cu->proc == proc && cu->context == context) {
219			*cup = cu->next;
220			xfree(cu);
221			return;
222		}
223	}
224	fatal("fatal_remove_cleanup: no such cleanup function: 0x%lx 0x%lx",
225	    (u_long) proc, (u_long) context);
226}
227
228/* Cleanup and exit */
229void
230fatal_cleanup(void)
231{
232	struct fatal_cleanup *cu, *next_cu;
233	static int called = 0;
234
235	if (called)
236		exit(255);
237	called = 1;
238	/* Call cleanup functions. */
239	for (cu = fatal_cleanups; cu; cu = next_cu) {
240		next_cu = cu->next;
241		debug("Calling cleanup 0x%lx(0x%lx)",
242		    (u_long) cu->proc, (u_long) cu->context);
243		(*cu->proc) (cu->context);
244	}
245	exit(255);
246}
247
248
249/*
250 * Initialize the log.
251 */
252
253void
254log_init(char *av0, LogLevel level, SyslogFacility facility, int on_stderr)
255{
256	argv0 = av0;
257
258	switch (level) {
259	case SYSLOG_LEVEL_QUIET:
260	case SYSLOG_LEVEL_FATAL:
261	case SYSLOG_LEVEL_ERROR:
262	case SYSLOG_LEVEL_INFO:
263	case SYSLOG_LEVEL_VERBOSE:
264	case SYSLOG_LEVEL_DEBUG1:
265	case SYSLOG_LEVEL_DEBUG2:
266	case SYSLOG_LEVEL_DEBUG3:
267		log_level = level;
268		break;
269	default:
270		fprintf(stderr, "Unrecognized internal syslog level code %d\n",
271		    (int) level);
272		exit(1);
273	}
274
275	log_on_stderr = on_stderr;
276	if (on_stderr)
277		return;
278
279	switch (facility) {
280	case SYSLOG_FACILITY_DAEMON:
281		log_facility = LOG_DAEMON;
282		break;
283	case SYSLOG_FACILITY_USER:
284		log_facility = LOG_USER;
285		break;
286	case SYSLOG_FACILITY_AUTH:
287		log_facility = LOG_AUTH;
288		break;
289	case SYSLOG_FACILITY_LOCAL0:
290		log_facility = LOG_LOCAL0;
291		break;
292	case SYSLOG_FACILITY_LOCAL1:
293		log_facility = LOG_LOCAL1;
294		break;
295	case SYSLOG_FACILITY_LOCAL2:
296		log_facility = LOG_LOCAL2;
297		break;
298	case SYSLOG_FACILITY_LOCAL3:
299		log_facility = LOG_LOCAL3;
300		break;
301	case SYSLOG_FACILITY_LOCAL4:
302		log_facility = LOG_LOCAL4;
303		break;
304	case SYSLOG_FACILITY_LOCAL5:
305		log_facility = LOG_LOCAL5;
306		break;
307	case SYSLOG_FACILITY_LOCAL6:
308		log_facility = LOG_LOCAL6;
309		break;
310	case SYSLOG_FACILITY_LOCAL7:
311		log_facility = LOG_LOCAL7;
312		break;
313	default:
314		fprintf(stderr,
315		    "Unrecognized internal syslog facility code %d\n",
316		    (int) facility);
317		exit(1);
318	}
319}
320
321#define MSGBUFSIZ 1024
322
323static void
324do_log(LogLevel level, const char *fmt, va_list args)
325{
326	char msgbuf[MSGBUFSIZ];
327	char fmtbuf[MSGBUFSIZ];
328	char *txt = NULL;
329	int pri = LOG_INFO;
330
331	if (level > log_level)
332		return;
333
334	switch (level) {
335	case SYSLOG_LEVEL_FATAL:
336		if (!log_on_stderr)
337			txt = "fatal";
338		pri = LOG_CRIT;
339		break;
340	case SYSLOG_LEVEL_ERROR:
341		if (!log_on_stderr)
342			txt = "error";
343		pri = LOG_ERR;
344		break;
345	case SYSLOG_LEVEL_INFO:
346		pri = LOG_INFO;
347		break;
348	case SYSLOG_LEVEL_VERBOSE:
349		pri = LOG_INFO;
350		break;
351	case SYSLOG_LEVEL_DEBUG1:
352		txt = "debug1";
353		pri = LOG_DEBUG;
354		break;
355	case SYSLOG_LEVEL_DEBUG2:
356		txt = "debug2";
357		pri = LOG_DEBUG;
358		break;
359	case SYSLOG_LEVEL_DEBUG3:
360		txt = "debug3";
361		pri = LOG_DEBUG;
362		break;
363	default:
364		txt = "internal error";
365		pri = LOG_ERR;
366		break;
367	}
368	if (txt != NULL) {
369		snprintf(fmtbuf, sizeof(fmtbuf), "%s: %s", txt, fmt);
370		vsnprintf(msgbuf, sizeof(msgbuf), fmtbuf, args);
371	} else {
372		vsnprintf(msgbuf, sizeof(msgbuf), fmt, args);
373	}
374	if (log_on_stderr) {
375		fprintf(stderr, "%s\r\n", msgbuf);
376	} else {
377		openlog(argv0 ? argv0 : __progname, LOG_PID, log_facility);
378		syslog(pri, "%.500s", msgbuf);
379		closelog();
380	}
381}
382