xref: /freebsd/crypto/openssh/log.c (revision ad30f8e79bd1007cc2476e491bd21b4f5e389e0a)
1 /* $OpenBSD: log.c,v 1.41 2008/06/10 04:50:25 dtucker Exp $ */
2 /*
3  * Author: Tatu Ylonen <ylo@cs.hut.fi>
4  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5  *                    All rights reserved
6  *
7  * As far as I am concerned, the code I have written for this software
8  * can be used freely for any purpose.  Any derived versions of this
9  * software must be clearly marked as such, and if the derived work is
10  * incompatible with the protocol description in the RFC file, it must be
11  * called by a name other than "ssh" or "Secure Shell".
12  */
13 /*
14  * Copyright (c) 2000 Markus Friedl.  All rights reserved.
15  *
16  * Redistribution and use in source and binary forms, with or without
17  * modification, are permitted provided that the following conditions
18  * are met:
19  * 1. Redistributions of source code must retain the above copyright
20  *    notice, this list of conditions and the following disclaimer.
21  * 2. Redistributions in binary form must reproduce the above copyright
22  *    notice, this list of conditions and the following disclaimer in the
23  *    documentation and/or other materials provided with the distribution.
24  *
25  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
26  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
27  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
28  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
29  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
30  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
31  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
32  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
33  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
34  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
35  */
36 
37 #include "includes.h"
38 
39 #include <sys/types.h>
40 
41 #include <stdarg.h>
42 #include <stdio.h>
43 #include <stdlib.h>
44 #include <string.h>
45 #include <syslog.h>
46 #include <unistd.h>
47 #include <errno.h>
48 #if defined(HAVE_STRNVIS) && defined(HAVE_VIS_H)
49 # include <vis.h>
50 #endif
51 
52 #include "xmalloc.h"
53 #include "log.h"
54 
55 static LogLevel log_level = SYSLOG_LEVEL_INFO;
56 static int log_on_stderr = 1;
57 static int log_facility = LOG_AUTH;
58 static char *argv0;
59 
60 extern char *__progname;
61 
62 #define LOG_SYSLOG_VIS	(VIS_CSTYLE|VIS_NL|VIS_TAB|VIS_OCTAL)
63 #define LOG_STDERR_VIS	(VIS_SAFE|VIS_OCTAL)
64 
65 /* textual representation of log-facilities/levels */
66 
67 static struct {
68 	const char *name;
69 	SyslogFacility val;
70 } log_facilities[] = {
71 	{ "DAEMON",	SYSLOG_FACILITY_DAEMON },
72 	{ "USER",	SYSLOG_FACILITY_USER },
73 	{ "AUTH",	SYSLOG_FACILITY_AUTH },
74 #ifdef LOG_AUTHPRIV
75 	{ "AUTHPRIV",	SYSLOG_FACILITY_AUTHPRIV },
76 #endif
77 	{ "LOCAL0",	SYSLOG_FACILITY_LOCAL0 },
78 	{ "LOCAL1",	SYSLOG_FACILITY_LOCAL1 },
79 	{ "LOCAL2",	SYSLOG_FACILITY_LOCAL2 },
80 	{ "LOCAL3",	SYSLOG_FACILITY_LOCAL3 },
81 	{ "LOCAL4",	SYSLOG_FACILITY_LOCAL4 },
82 	{ "LOCAL5",	SYSLOG_FACILITY_LOCAL5 },
83 	{ "LOCAL6",	SYSLOG_FACILITY_LOCAL6 },
84 	{ "LOCAL7",	SYSLOG_FACILITY_LOCAL7 },
85 	{ NULL,		SYSLOG_FACILITY_NOT_SET }
86 };
87 
88 static struct {
89 	const char *name;
90 	LogLevel val;
91 } log_levels[] =
92 {
93 	{ "QUIET",	SYSLOG_LEVEL_QUIET },
94 	{ "FATAL",	SYSLOG_LEVEL_FATAL },
95 	{ "ERROR",	SYSLOG_LEVEL_ERROR },
96 	{ "INFO",	SYSLOG_LEVEL_INFO },
97 	{ "VERBOSE",	SYSLOG_LEVEL_VERBOSE },
98 	{ "DEBUG",	SYSLOG_LEVEL_DEBUG1 },
99 	{ "DEBUG1",	SYSLOG_LEVEL_DEBUG1 },
100 	{ "DEBUG2",	SYSLOG_LEVEL_DEBUG2 },
101 	{ "DEBUG3",	SYSLOG_LEVEL_DEBUG3 },
102 	{ NULL,		SYSLOG_LEVEL_NOT_SET }
103 };
104 
105 SyslogFacility
106 log_facility_number(char *name)
107 {
108 	int i;
109 
110 	if (name != NULL)
111 		for (i = 0; log_facilities[i].name; i++)
112 			if (strcasecmp(log_facilities[i].name, name) == 0)
113 				return log_facilities[i].val;
114 	return SYSLOG_FACILITY_NOT_SET;
115 }
116 
117 const char *
118 log_facility_name(SyslogFacility facility)
119 {
120 	u_int i;
121 
122 	for (i = 0;  log_facilities[i].name; i++)
123 		if (log_facilities[i].val == facility)
124 			return log_facilities[i].name;
125 	return NULL;
126 }
127 
128 LogLevel
129 log_level_number(char *name)
130 {
131 	int i;
132 
133 	if (name != NULL)
134 		for (i = 0; log_levels[i].name; i++)
135 			if (strcasecmp(log_levels[i].name, name) == 0)
136 				return log_levels[i].val;
137 	return SYSLOG_LEVEL_NOT_SET;
138 }
139 
140 const char *
141 log_level_name(LogLevel level)
142 {
143 	u_int i;
144 
145 	for (i = 0; log_levels[i].name != NULL; i++)
146 		if (log_levels[i].val == level)
147 			return log_levels[i].name;
148 	return NULL;
149 }
150 
151 /* Error messages that should be logged. */
152 
153 void
154 error(const char *fmt,...)
155 {
156 	va_list args;
157 
158 	va_start(args, fmt);
159 	do_log(SYSLOG_LEVEL_ERROR, fmt, args);
160 	va_end(args);
161 }
162 
163 void
164 sigdie(const char *fmt,...)
165 {
166 #ifdef DO_LOG_SAFE_IN_SIGHAND
167 	va_list args;
168 
169 	va_start(args, fmt);
170 	do_log(SYSLOG_LEVEL_FATAL, fmt, args);
171 	va_end(args);
172 #endif
173 	_exit(1);
174 }
175 
176 
177 /* Log this message (information that usually should go to the log). */
178 
179 void
180 logit(const char *fmt,...)
181 {
182 	va_list args;
183 
184 	va_start(args, fmt);
185 	do_log(SYSLOG_LEVEL_INFO, fmt, args);
186 	va_end(args);
187 }
188 
189 /* More detailed messages (information that does not need to go to the log). */
190 
191 void
192 verbose(const char *fmt,...)
193 {
194 	va_list args;
195 
196 	va_start(args, fmt);
197 	do_log(SYSLOG_LEVEL_VERBOSE, fmt, args);
198 	va_end(args);
199 }
200 
201 /* Debugging messages that should not be logged during normal operation. */
202 
203 void
204 debug(const char *fmt,...)
205 {
206 	va_list args;
207 
208 	va_start(args, fmt);
209 	do_log(SYSLOG_LEVEL_DEBUG1, fmt, args);
210 	va_end(args);
211 }
212 
213 void
214 debug2(const char *fmt,...)
215 {
216 	va_list args;
217 
218 	va_start(args, fmt);
219 	do_log(SYSLOG_LEVEL_DEBUG2, fmt, args);
220 	va_end(args);
221 }
222 
223 void
224 debug3(const char *fmt,...)
225 {
226 	va_list args;
227 
228 	va_start(args, fmt);
229 	do_log(SYSLOG_LEVEL_DEBUG3, fmt, args);
230 	va_end(args);
231 }
232 
233 /*
234  * Initialize the log.
235  */
236 
237 void
238 log_init(char *av0, LogLevel level, SyslogFacility facility, int on_stderr)
239 {
240 #if defined(HAVE_OPENLOG_R) && defined(SYSLOG_DATA_INIT)
241 	struct syslog_data sdata = SYSLOG_DATA_INIT;
242 #endif
243 
244 	argv0 = av0;
245 
246 	switch (level) {
247 	case SYSLOG_LEVEL_QUIET:
248 	case SYSLOG_LEVEL_FATAL:
249 	case SYSLOG_LEVEL_ERROR:
250 	case SYSLOG_LEVEL_INFO:
251 	case SYSLOG_LEVEL_VERBOSE:
252 	case SYSLOG_LEVEL_DEBUG1:
253 	case SYSLOG_LEVEL_DEBUG2:
254 	case SYSLOG_LEVEL_DEBUG3:
255 		log_level = level;
256 		break;
257 	default:
258 		fprintf(stderr, "Unrecognized internal syslog level code %d\n",
259 		    (int) level);
260 		exit(1);
261 	}
262 
263 	log_on_stderr = on_stderr;
264 	if (on_stderr)
265 		return;
266 
267 	switch (facility) {
268 	case SYSLOG_FACILITY_DAEMON:
269 		log_facility = LOG_DAEMON;
270 		break;
271 	case SYSLOG_FACILITY_USER:
272 		log_facility = LOG_USER;
273 		break;
274 	case SYSLOG_FACILITY_AUTH:
275 		log_facility = LOG_AUTH;
276 		break;
277 #ifdef LOG_AUTHPRIV
278 	case SYSLOG_FACILITY_AUTHPRIV:
279 		log_facility = LOG_AUTHPRIV;
280 		break;
281 #endif
282 	case SYSLOG_FACILITY_LOCAL0:
283 		log_facility = LOG_LOCAL0;
284 		break;
285 	case SYSLOG_FACILITY_LOCAL1:
286 		log_facility = LOG_LOCAL1;
287 		break;
288 	case SYSLOG_FACILITY_LOCAL2:
289 		log_facility = LOG_LOCAL2;
290 		break;
291 	case SYSLOG_FACILITY_LOCAL3:
292 		log_facility = LOG_LOCAL3;
293 		break;
294 	case SYSLOG_FACILITY_LOCAL4:
295 		log_facility = LOG_LOCAL4;
296 		break;
297 	case SYSLOG_FACILITY_LOCAL5:
298 		log_facility = LOG_LOCAL5;
299 		break;
300 	case SYSLOG_FACILITY_LOCAL6:
301 		log_facility = LOG_LOCAL6;
302 		break;
303 	case SYSLOG_FACILITY_LOCAL7:
304 		log_facility = LOG_LOCAL7;
305 		break;
306 	default:
307 		fprintf(stderr,
308 		    "Unrecognized internal syslog facility code %d\n",
309 		    (int) facility);
310 		exit(1);
311 	}
312 
313 	/*
314 	 * If an external library (eg libwrap) attempts to use syslog
315 	 * immediately after reexec, syslog may be pointing to the wrong
316 	 * facility, so we force an open/close of syslog here.
317 	 */
318 #if defined(HAVE_OPENLOG_R) && defined(SYSLOG_DATA_INIT)
319 	openlog_r(argv0 ? argv0 : __progname, LOG_PID, log_facility, &sdata);
320 	closelog_r(&sdata);
321 #else
322 	openlog(argv0 ? argv0 : __progname, LOG_PID, log_facility);
323 	closelog();
324 #endif
325 }
326 
327 #define MSGBUFSIZ 1024
328 
329 void
330 do_log(LogLevel level, const char *fmt, va_list args)
331 {
332 #if defined(HAVE_OPENLOG_R) && defined(SYSLOG_DATA_INIT)
333 	struct syslog_data sdata = SYSLOG_DATA_INIT;
334 #endif
335 	char msgbuf[MSGBUFSIZ];
336 	char fmtbuf[MSGBUFSIZ];
337 	char *txt = NULL;
338 	int pri = LOG_INFO;
339 	int saved_errno = errno;
340 
341 	if (level > log_level)
342 		return;
343 
344 	switch (level) {
345 	case SYSLOG_LEVEL_FATAL:
346 		if (!log_on_stderr)
347 			txt = "fatal";
348 		pri = LOG_CRIT;
349 		break;
350 	case SYSLOG_LEVEL_ERROR:
351 		if (!log_on_stderr)
352 			txt = "error";
353 		pri = LOG_ERR;
354 		break;
355 	case SYSLOG_LEVEL_INFO:
356 		pri = LOG_INFO;
357 		break;
358 	case SYSLOG_LEVEL_VERBOSE:
359 		pri = LOG_INFO;
360 		break;
361 	case SYSLOG_LEVEL_DEBUG1:
362 		txt = "debug1";
363 		pri = LOG_DEBUG;
364 		break;
365 	case SYSLOG_LEVEL_DEBUG2:
366 		txt = "debug2";
367 		pri = LOG_DEBUG;
368 		break;
369 	case SYSLOG_LEVEL_DEBUG3:
370 		txt = "debug3";
371 		pri = LOG_DEBUG;
372 		break;
373 	default:
374 		txt = "internal error";
375 		pri = LOG_ERR;
376 		break;
377 	}
378 	if (txt != NULL) {
379 		snprintf(fmtbuf, sizeof(fmtbuf), "%s: %s", txt, fmt);
380 		vsnprintf(msgbuf, sizeof(msgbuf), fmtbuf, args);
381 	} else {
382 		vsnprintf(msgbuf, sizeof(msgbuf), fmt, args);
383 	}
384 	strnvis(fmtbuf, msgbuf, sizeof(fmtbuf),
385 	    log_on_stderr ? LOG_STDERR_VIS : LOG_SYSLOG_VIS);
386 	if (log_on_stderr) {
387 		snprintf(msgbuf, sizeof msgbuf, "%s\r\n", fmtbuf);
388 		write(STDERR_FILENO, msgbuf, strlen(msgbuf));
389 	} else {
390 #if defined(HAVE_OPENLOG_R) && defined(SYSLOG_DATA_INIT)
391 		openlog_r(argv0 ? argv0 : __progname, LOG_PID, log_facility, &sdata);
392 		syslog_r(pri, &sdata, "%.500s", fmtbuf);
393 		closelog_r(&sdata);
394 #else
395 		openlog(argv0 ? argv0 : __progname, LOG_PID, log_facility);
396 		syslog(pri, "%.500s", fmtbuf);
397 		closelog();
398 #endif
399 	}
400 	errno = saved_errno;
401 }
402