xref: /netbsd-src/crypto/external/bsd/openssh/dist/log.c (revision d909946ca08dceb44d7d0f22ec9488679695d976)
1 /*	$NetBSD: log.c,v 1.14 2016/08/02 13:45:12 christos Exp $	*/
2 /* $OpenBSD: log.c,v 1.48 2016/07/15 05:01:58 dtucker Exp $ */
3 /*
4  * Author: Tatu Ylonen <ylo@cs.hut.fi>
5  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
6  *                    All rights reserved
7  *
8  * As far as I am concerned, the code I have written for this software
9  * can be used freely for any purpose.  Any derived versions of this
10  * software must be clearly marked as such, and if the derived work is
11  * incompatible with the protocol description in the RFC file, it must be
12  * called by a name other than "ssh" or "Secure Shell".
13  */
14 /*
15  * Copyright (c) 2000 Markus Friedl.  All rights reserved.
16  *
17  * Redistribution and use in source and binary forms, with or without
18  * modification, are permitted provided that the following conditions
19  * are met:
20  * 1. Redistributions of source code must retain the above copyright
21  *    notice, this list of conditions and the following disclaimer.
22  * 2. Redistributions in binary form must reproduce the above copyright
23  *    notice, this list of conditions and the following disclaimer in the
24  *    documentation and/or other materials provided with the distribution.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
27  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
28  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
29  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
30  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
31  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
32  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
33  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
34  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
35  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
36  */
37 
38 #include "includes.h"
39 __RCSID("$NetBSD: log.c,v 1.14 2016/08/02 13:45:12 christos Exp $");
40 #include <sys/types.h>
41 #include <sys/uio.h>
42 
43 #include <fcntl.h>
44 #include <stdarg.h>
45 #include <stdio.h>
46 #include <stdlib.h>
47 #include <string.h>
48 #include <syslog.h>
49 #include <unistd.h>
50 #include <errno.h>
51 #include <vis.h>
52 
53 #include "log.h"
54 
55 static LogLevel log_level = SYSLOG_LEVEL_INFO;
56 static int log_on_stderr = 1;
57 static int log_stderr_fd = STDERR_FILENO;
58 static int log_facility = LOG_AUTH;
59 static const char *argv0;
60 static log_handler_fn *log_handler;
61 static void *log_handler_ctx;
62 
63 extern char *__progname;
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 	{ "LOCAL0",	SYSLOG_FACILITY_LOCAL0 },
75 	{ "LOCAL1",	SYSLOG_FACILITY_LOCAL1 },
76 	{ "LOCAL2",	SYSLOG_FACILITY_LOCAL2 },
77 	{ "LOCAL3",	SYSLOG_FACILITY_LOCAL3 },
78 	{ "LOCAL4",	SYSLOG_FACILITY_LOCAL4 },
79 	{ "LOCAL5",	SYSLOG_FACILITY_LOCAL5 },
80 	{ "LOCAL6",	SYSLOG_FACILITY_LOCAL6 },
81 	{ "LOCAL7",	SYSLOG_FACILITY_LOCAL7 },
82 	{ NULL,		SYSLOG_FACILITY_NOT_SET }
83 };
84 
85 static struct {
86 	const char *name;
87 	LogLevel val;
88 } log_levels[] =
89 {
90 	{ "QUIET",	SYSLOG_LEVEL_QUIET },
91 	{ "FATAL",	SYSLOG_LEVEL_FATAL },
92 	{ "ERROR",	SYSLOG_LEVEL_ERROR },
93 	{ "INFO",	SYSLOG_LEVEL_INFO },
94 	{ "VERBOSE",	SYSLOG_LEVEL_VERBOSE },
95 	{ "DEBUG",	SYSLOG_LEVEL_DEBUG1 },
96 	{ "DEBUG1",	SYSLOG_LEVEL_DEBUG1 },
97 	{ "DEBUG2",	SYSLOG_LEVEL_DEBUG2 },
98 	{ "DEBUG3",	SYSLOG_LEVEL_DEBUG3 },
99 	{ NULL,		SYSLOG_LEVEL_NOT_SET }
100 };
101 
102 SyslogFacility
103 log_facility_number(char *name)
104 {
105 	int i;
106 
107 	if (name != NULL)
108 		for (i = 0; log_facilities[i].name; i++)
109 			if (strcasecmp(log_facilities[i].name, name) == 0)
110 				return log_facilities[i].val;
111 	return SYSLOG_FACILITY_NOT_SET;
112 }
113 
114 const char *
115 log_facility_name(SyslogFacility facility)
116 {
117 	u_int i;
118 
119 	for (i = 0;  log_facilities[i].name; i++)
120 		if (log_facilities[i].val == facility)
121 			return log_facilities[i].name;
122 	return NULL;
123 }
124 
125 LogLevel
126 log_level_number(char *name)
127 {
128 	int i;
129 
130 	if (name != NULL)
131 		for (i = 0; log_levels[i].name; i++)
132 			if (strcasecmp(log_levels[i].name, name) == 0)
133 				return log_levels[i].val;
134 	return SYSLOG_LEVEL_NOT_SET;
135 }
136 
137 const char *
138 log_level_name(LogLevel level)
139 {
140 	u_int i;
141 
142 	for (i = 0; log_levels[i].name != NULL; i++)
143 		if (log_levels[i].val == level)
144 			return log_levels[i].name;
145 	return NULL;
146 }
147 
148 /* Error messages that should be logged. */
149 
150 void
151 error(const char *fmt,...)
152 {
153 	va_list args;
154 
155 	va_start(args, fmt);
156 	do_log(SYSLOG_LEVEL_ERROR, fmt, args);
157 	va_end(args);
158 }
159 
160 void
161 sigdie(const char *fmt,...)
162 {
163 	va_list args;
164 
165 	va_start(args, fmt);
166 	do_log(SYSLOG_LEVEL_FATAL, fmt, args);
167 	va_end(args);
168 	_exit(1);
169 }
170 
171 void
172 logdie(const char *fmt,...)
173 {
174 	va_list args;
175 
176 	va_start(args, fmt);
177 	do_log(SYSLOG_LEVEL_INFO, fmt, args);
178 	va_end(args);
179 	cleanup_exit(255);
180 }
181 
182 /* Log this message (information that usually should go to the log). */
183 
184 void
185 logit(const char *fmt,...)
186 {
187 	va_list args;
188 
189 	va_start(args, fmt);
190 	do_log(SYSLOG_LEVEL_INFO, fmt, args);
191 	va_end(args);
192 }
193 
194 /* More detailed messages (information that does not need to go to the log). */
195 
196 void
197 verbose(const char *fmt,...)
198 {
199 	va_list args;
200 
201 	va_start(args, fmt);
202 	do_log(SYSLOG_LEVEL_VERBOSE, fmt, args);
203 	va_end(args);
204 }
205 
206 /* Debugging messages that should not be logged during normal operation. */
207 
208 void
209 debug(const char *fmt,...)
210 {
211 	va_list args;
212 
213 	va_start(args, fmt);
214 	do_log(SYSLOG_LEVEL_DEBUG1, fmt, args);
215 	va_end(args);
216 }
217 
218 void
219 debug2(const char *fmt,...)
220 {
221 	va_list args;
222 
223 	va_start(args, fmt);
224 	do_log(SYSLOG_LEVEL_DEBUG2, fmt, args);
225 	va_end(args);
226 }
227 
228 void
229 debug3(const char *fmt,...)
230 {
231 	va_list args;
232 
233 	va_start(args, fmt);
234 	do_log(SYSLOG_LEVEL_DEBUG3, fmt, args);
235 	va_end(args);
236 }
237 
238 /*
239  * Initialize the log.
240  */
241 
242 void
243 log_init(const char *av0, LogLevel level, SyslogFacility facility,
244     int on_stderr)
245 {
246 	argv0 = av0;
247 
248 	switch (level) {
249 	case SYSLOG_LEVEL_QUIET:
250 	case SYSLOG_LEVEL_FATAL:
251 	case SYSLOG_LEVEL_ERROR:
252 	case SYSLOG_LEVEL_INFO:
253 	case SYSLOG_LEVEL_VERBOSE:
254 	case SYSLOG_LEVEL_DEBUG1:
255 	case SYSLOG_LEVEL_DEBUG2:
256 	case SYSLOG_LEVEL_DEBUG3:
257 		log_level = level;
258 		break;
259 	default:
260 		fprintf(stderr, "Unrecognized internal syslog level code %d\n",
261 		    (int) level);
262 		exit(1);
263 	}
264 
265 	log_handler = NULL;
266 	log_handler_ctx = NULL;
267 
268 	log_on_stderr = on_stderr;
269 	if (on_stderr)
270 		return;
271 
272 	switch (facility) {
273 	case SYSLOG_FACILITY_DAEMON:
274 		log_facility = LOG_DAEMON;
275 		break;
276 	case SYSLOG_FACILITY_USER:
277 		log_facility = LOG_USER;
278 		break;
279 	case SYSLOG_FACILITY_AUTH:
280 		log_facility = LOG_AUTH;
281 		break;
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 void
315 log_change_level(LogLevel new_log_level)
316 {
317 	/* no-op if log_init has not been called */
318 	if (argv0 == NULL)
319 		return;
320 	log_init(argv0, new_log_level, log_facility, log_on_stderr);
321 }
322 
323 int
324 log_is_on_stderr(void)
325 {
326 	return log_on_stderr && log_stderr_fd == STDERR_FILENO;
327 }
328 
329 /* redirect what would usually get written to stderr to specified file */
330 void
331 log_redirect_stderr_to(const char *logfile)
332 {
333 	int fd;
334 
335 	if ((fd = open(logfile, O_WRONLY|O_CREAT|O_APPEND, 0600)) == -1) {
336 		fprintf(stderr, "Couldn't open logfile %s: %s\n", logfile,
337 		     strerror(errno));
338 		exit(1);
339 	}
340 	log_stderr_fd = fd;
341 }
342 
343 #define MSGBUFSIZ 1024
344 
345 void
346 set_log_handler(log_handler_fn *handler, void *ctx)
347 {
348 	log_handler = handler;
349 	log_handler_ctx = ctx;
350 }
351 
352 void
353 do_log2(LogLevel level, const char *fmt,...)
354 {
355 	va_list args;
356 
357 	va_start(args, fmt);
358 	do_log(level, fmt, args);
359 	va_end(args);
360 }
361 
362 void
363 do_log(LogLevel level, const char *fmt, va_list args)
364 {
365 #ifdef SYSLOG_DATA_INIT
366 	struct syslog_data sdata = SYSLOG_DATA_INIT;
367 #endif
368 	char msgbuf[MSGBUFSIZ], *msgbufp;
369 	char visbuf[MSGBUFSIZ * 4 + 1];
370 	size_t len, len2;
371 	const char *txt = NULL;
372 	int pri = LOG_INFO;
373 	int saved_errno = errno;
374 	log_handler_fn *tmp_handler;
375 
376 	if (level > log_level)
377 		return;
378 
379 	switch (level) {
380 	case SYSLOG_LEVEL_FATAL:
381 		if (!log_on_stderr)
382 			txt = "fatal";
383 		pri = LOG_CRIT;
384 		break;
385 	case SYSLOG_LEVEL_ERROR:
386 		if (!log_on_stderr)
387 			txt = "error";
388 		pri = LOG_ERR;
389 		break;
390 	case SYSLOG_LEVEL_INFO:
391 		pri = LOG_INFO;
392 		break;
393 	case SYSLOG_LEVEL_VERBOSE:
394 		pri = LOG_INFO;
395 		break;
396 	case SYSLOG_LEVEL_DEBUG1:
397 		txt = "debug1";
398 		pri = LOG_DEBUG;
399 		break;
400 	case SYSLOG_LEVEL_DEBUG2:
401 		txt = "debug2";
402 		pri = LOG_DEBUG;
403 		break;
404 	case SYSLOG_LEVEL_DEBUG3:
405 		txt = "debug3";
406 		pri = LOG_DEBUG;
407 		break;
408 	default:
409 		txt = "internal error";
410 		pri = LOG_ERR;
411 		break;
412 	}
413 	len = sizeof(msgbuf);
414 	msgbufp = msgbuf;
415 	if (txt != NULL && log_handler == NULL) {
416 		len2 = strlen(txt);
417 		if (len2 > len - 2)
418 			len2 = len - 2;
419 		memcpy(msgbufp, txt, len2);
420 		msgbufp += len2;
421 		*msgbufp++ = ':';
422 		*msgbufp++ = ' ';
423 		len -= len2 + 2;
424 	}
425 	vsnprintf(msgbufp, len, fmt, args);
426 	strnvis(visbuf, sizeof(visbuf), msgbuf, VIS_SAFE|VIS_OCTAL);
427 	if (log_handler != NULL) {
428 		/* Avoid recursion */
429 		tmp_handler = log_handler;
430 		log_handler = NULL;
431 		tmp_handler(level, visbuf, log_handler_ctx);
432 		log_handler = tmp_handler;
433 	} else if (log_on_stderr) {
434 		snprintf(msgbuf, sizeof msgbuf, "%s\r\n", visbuf);
435 		(void)write(log_stderr_fd, msgbuf, strlen(msgbuf));
436 	} else {
437 #ifdef SYSLOG_DATA_INIT
438 		openlog_r(argv0 ? argv0 : __progname, LOG_PID, log_facility, &sdata);
439 		syslog_r(pri, &sdata, "%.500s", visbuf);
440 		closelog_r(&sdata);
441 #else
442 		openlog(argv0 ? argv0 : __progname, LOG_PID, log_facility);
443 		syslog(pri, "%.500s", visbuf);
444 		closelog();
445 #endif
446 	}
447 	errno = saved_errno;
448 }
449