xref: /freebsd/crypto/openssh/log.c (revision 41466b50c1d5bfd1cf6adaae547a579a75d7c04e)
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"
37 RCSID("$OpenBSD: log.c,v 1.17 2001/03/04 17:42:28 millert Exp $");
38 
39 #include "log.h"
40 #include "xmalloc.h"
41 
42 #include <syslog.h>
43 
44 static LogLevel log_level = SYSLOG_LEVEL_INFO;
45 static int log_on_stderr = 1;
46 static int log_facility = LOG_AUTH;
47 static char *argv0;
48 
49 extern char *__progname;
50 
51 /* textual representation of log-facilities/levels */
52 
53 static 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, 0 }
69 };
70 
71 static 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, 0 }
86 };
87 
88 SyslogFacility
89 log_facility_number(char *name)
90 {
91 	int i;
92 	if (name != NULL)
93 		for (i = 0; log_facilities[i].name; i++)
94 			if (strcasecmp(log_facilities[i].name, name) == 0)
95 				return log_facilities[i].val;
96 	return (SyslogFacility) - 1;
97 }
98 
99 LogLevel
100 log_level_number(char *name)
101 {
102 	int i;
103 	if (name != NULL)
104 		for (i = 0; log_levels[i].name; i++)
105 			if (strcasecmp(log_levels[i].name, name) == 0)
106 				return log_levels[i].val;
107 	return (LogLevel) - 1;
108 }
109 /* Fatal messages.  This function never returns. */
110 
111 void
112 fatal(const char *fmt,...)
113 {
114 	va_list args;
115 	va_start(args, fmt);
116 	do_log(SYSLOG_LEVEL_FATAL, fmt, args);
117 	va_end(args);
118 	fatal_cleanup();
119 }
120 
121 /* Error messages that should be logged. */
122 
123 void
124 error(const char *fmt,...)
125 {
126 	va_list args;
127 	va_start(args, fmt);
128 	do_log(SYSLOG_LEVEL_ERROR, fmt, args);
129 	va_end(args);
130 }
131 
132 /* Log this message (information that usually should go to the log). */
133 
134 void
135 log(const char *fmt,...)
136 {
137 	va_list args;
138 	va_start(args, fmt);
139 	do_log(SYSLOG_LEVEL_INFO, fmt, args);
140 	va_end(args);
141 }
142 
143 /* More detailed messages (information that does not need to go to the log). */
144 
145 void
146 verbose(const char *fmt,...)
147 {
148 	va_list args;
149 	va_start(args, fmt);
150 	do_log(SYSLOG_LEVEL_VERBOSE, fmt, args);
151 	va_end(args);
152 }
153 
154 /* Debugging messages that should not be logged during normal operation. */
155 
156 void
157 debug(const char *fmt,...)
158 {
159 	va_list args;
160 	va_start(args, fmt);
161 	do_log(SYSLOG_LEVEL_DEBUG1, fmt, args);
162 	va_end(args);
163 }
164 
165 void
166 debug2(const char *fmt,...)
167 {
168 	va_list args;
169 	va_start(args, fmt);
170 	do_log(SYSLOG_LEVEL_DEBUG2, fmt, args);
171 	va_end(args);
172 }
173 
174 void
175 debug3(const char *fmt,...)
176 {
177 	va_list args;
178 	va_start(args, fmt);
179 	do_log(SYSLOG_LEVEL_DEBUG3, fmt, args);
180 	va_end(args);
181 }
182 
183 /* Fatal cleanup */
184 
185 struct fatal_cleanup {
186 	struct fatal_cleanup *next;
187 	void (*proc) (void *);
188 	void *context;
189 };
190 
191 static struct fatal_cleanup *fatal_cleanups = NULL;
192 
193 /* Registers a cleanup function to be called by fatal() before exiting. */
194 
195 void
196 fatal_add_cleanup(void (*proc) (void *), void *context)
197 {
198 	struct fatal_cleanup *cu;
199 
200 	cu = xmalloc(sizeof(*cu));
201 	cu->proc = proc;
202 	cu->context = context;
203 	cu->next = fatal_cleanups;
204 	fatal_cleanups = cu;
205 }
206 
207 /* Removes a cleanup frunction to be called at fatal(). */
208 
209 void
210 fatal_remove_cleanup(void (*proc) (void *context), void *context)
211 {
212 	struct fatal_cleanup **cup, *cu;
213 
214 	for (cup = &fatal_cleanups; *cup; cup = &cu->next) {
215 		cu = *cup;
216 		if (cu->proc == proc && cu->context == context) {
217 			*cup = cu->next;
218 			xfree(cu);
219 			return;
220 		}
221 	}
222 	fatal("fatal_remove_cleanup: no such cleanup function: 0x%lx 0x%lx",
223 	    (u_long) proc, (u_long) context);
224 }
225 
226 /* Cleanup and exit */
227 void
228 fatal_cleanup(void)
229 {
230 	struct fatal_cleanup *cu, *next_cu;
231 	static int called = 0;
232 
233 	if (called)
234 		exit(255);
235 	called = 1;
236 	/* Call cleanup functions. */
237 	for (cu = fatal_cleanups; cu; cu = next_cu) {
238 		next_cu = cu->next;
239 		debug("Calling cleanup 0x%lx(0x%lx)",
240 		      (u_long) cu->proc, (u_long) cu->context);
241 		(*cu->proc) (cu->context);
242 	}
243 	exit(255);
244 }
245 
246 
247 /*
248  * Initialize the log.
249  */
250 
251 void
252 log_init(char *av0, LogLevel level, SyslogFacility facility, int on_stderr)
253 {
254 	argv0 = av0;
255 
256 	switch (level) {
257 	case SYSLOG_LEVEL_QUIET:
258 	case SYSLOG_LEVEL_FATAL:
259 	case SYSLOG_LEVEL_ERROR:
260 	case SYSLOG_LEVEL_INFO:
261 	case SYSLOG_LEVEL_VERBOSE:
262 	case SYSLOG_LEVEL_DEBUG1:
263 	case SYSLOG_LEVEL_DEBUG2:
264 	case SYSLOG_LEVEL_DEBUG3:
265 		log_level = level;
266 		break;
267 	default:
268 		fprintf(stderr, "Unrecognized internal syslog level code %d\n",
269 		    (int) level);
270 		exit(1);
271 	}
272 
273 	log_on_stderr = on_stderr;
274 	if (on_stderr)
275 		return;
276 
277 	switch (facility) {
278 	case SYSLOG_FACILITY_DAEMON:
279 		log_facility = LOG_DAEMON;
280 		break;
281 	case SYSLOG_FACILITY_USER:
282 		log_facility = LOG_USER;
283 		break;
284 	case SYSLOG_FACILITY_AUTH:
285 		log_facility = LOG_AUTH;
286 		break;
287 	case SYSLOG_FACILITY_LOCAL0:
288 		log_facility = LOG_LOCAL0;
289 		break;
290 	case SYSLOG_FACILITY_LOCAL1:
291 		log_facility = LOG_LOCAL1;
292 		break;
293 	case SYSLOG_FACILITY_LOCAL2:
294 		log_facility = LOG_LOCAL2;
295 		break;
296 	case SYSLOG_FACILITY_LOCAL3:
297 		log_facility = LOG_LOCAL3;
298 		break;
299 	case SYSLOG_FACILITY_LOCAL4:
300 		log_facility = LOG_LOCAL4;
301 		break;
302 	case SYSLOG_FACILITY_LOCAL5:
303 		log_facility = LOG_LOCAL5;
304 		break;
305 	case SYSLOG_FACILITY_LOCAL6:
306 		log_facility = LOG_LOCAL6;
307 		break;
308 	case SYSLOG_FACILITY_LOCAL7:
309 		log_facility = LOG_LOCAL7;
310 		break;
311 	default:
312 		fprintf(stderr,
313 		    "Unrecognized internal syslog facility code %d\n",
314 		    (int) facility);
315 		exit(1);
316 	}
317 }
318 
319 #define MSGBUFSIZ 1024
320 
321 void
322 do_log(LogLevel level, const char *fmt, va_list args)
323 {
324 	char msgbuf[MSGBUFSIZ];
325 	char fmtbuf[MSGBUFSIZ];
326 	char *txt = NULL;
327 	int pri = LOG_INFO;
328 
329 	if (level > log_level)
330 		return;
331 
332 	switch (level) {
333 	case SYSLOG_LEVEL_FATAL:
334 		if (!log_on_stderr)
335 			txt = "fatal";
336 		pri = LOG_CRIT;
337 		break;
338 	case SYSLOG_LEVEL_ERROR:
339 		if (!log_on_stderr)
340 			txt = "error";
341 		pri = LOG_ERR;
342 		break;
343 	case SYSLOG_LEVEL_INFO:
344 		pri = LOG_INFO;
345 		break;
346 	case SYSLOG_LEVEL_VERBOSE:
347 		pri = LOG_INFO;
348 		break;
349 	case SYSLOG_LEVEL_DEBUG1:
350 		txt = "debug1";
351 		pri = LOG_DEBUG;
352 		break;
353 	case SYSLOG_LEVEL_DEBUG2:
354 		txt = "debug2";
355 		pri = LOG_DEBUG;
356 		break;
357 	case SYSLOG_LEVEL_DEBUG3:
358 		txt = "debug3";
359 		pri = LOG_DEBUG;
360 		break;
361 	default:
362 		txt = "internal error";
363 		pri = LOG_ERR;
364 		break;
365 	}
366 	if (txt != NULL) {
367 		snprintf(fmtbuf, sizeof(fmtbuf), "%s: %s", txt, fmt);
368 		vsnprintf(msgbuf, sizeof(msgbuf), fmtbuf, args);
369 	} else {
370 		vsnprintf(msgbuf, sizeof(msgbuf), fmt, args);
371 	}
372 	if (log_on_stderr) {
373 		fprintf(stderr, "%s\r\n", msgbuf);
374 	} else {
375 		openlog(argv0 ? argv0 : __progname, LOG_PID, log_facility);
376 		syslog(pri, "%.500s", msgbuf);
377 		closelog();
378 	}
379 }
380