1 /* $OpenBSD: log.c,v 1.42 2011/06/17 21:44:30 djm 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 static log_handler_fn *log_handler;
60 static void *log_handler_ctx;
61
62 extern char *__progname;
63
64 #define LOG_SYSLOG_VIS (VIS_CSTYLE|VIS_NL|VIS_TAB|VIS_OCTAL)
65 #define LOG_STDERR_VIS (VIS_SAFE|VIS_OCTAL)
66
67 /* textual representation of log-facilities/levels */
68
69 static struct {
70 const char *name;
71 SyslogFacility val;
72 } log_facilities[] = {
73 { "DAEMON", SYSLOG_FACILITY_DAEMON },
74 { "USER", SYSLOG_FACILITY_USER },
75 { "AUTH", SYSLOG_FACILITY_AUTH },
76 #ifdef LOG_AUTHPRIV
77 { "AUTHPRIV", SYSLOG_FACILITY_AUTHPRIV },
78 #endif
79 { "LOCAL0", SYSLOG_FACILITY_LOCAL0 },
80 { "LOCAL1", SYSLOG_FACILITY_LOCAL1 },
81 { "LOCAL2", SYSLOG_FACILITY_LOCAL2 },
82 { "LOCAL3", SYSLOG_FACILITY_LOCAL3 },
83 { "LOCAL4", SYSLOG_FACILITY_LOCAL4 },
84 { "LOCAL5", SYSLOG_FACILITY_LOCAL5 },
85 { "LOCAL6", SYSLOG_FACILITY_LOCAL6 },
86 { "LOCAL7", SYSLOG_FACILITY_LOCAL7 },
87 { NULL, SYSLOG_FACILITY_NOT_SET }
88 };
89
90 static struct {
91 const char *name;
92 LogLevel val;
93 } log_levels[] =
94 {
95 { "QUIET", SYSLOG_LEVEL_QUIET },
96 { "FATAL", SYSLOG_LEVEL_FATAL },
97 { "ERROR", SYSLOG_LEVEL_ERROR },
98 { "INFO", SYSLOG_LEVEL_INFO },
99 { "VERBOSE", SYSLOG_LEVEL_VERBOSE },
100 { "DEBUG", SYSLOG_LEVEL_DEBUG1 },
101 { "DEBUG1", SYSLOG_LEVEL_DEBUG1 },
102 { "DEBUG2", SYSLOG_LEVEL_DEBUG2 },
103 { "DEBUG3", SYSLOG_LEVEL_DEBUG3 },
104 { NULL, SYSLOG_LEVEL_NOT_SET }
105 };
106
107 SyslogFacility
log_facility_number(char * name)108 log_facility_number(char *name)
109 {
110 int i;
111
112 if (name != NULL)
113 for (i = 0; log_facilities[i].name; i++)
114 if (strcasecmp(log_facilities[i].name, name) == 0)
115 return log_facilities[i].val;
116 return SYSLOG_FACILITY_NOT_SET;
117 }
118
119 const char *
log_facility_name(SyslogFacility facility)120 log_facility_name(SyslogFacility facility)
121 {
122 u_int i;
123
124 for (i = 0; log_facilities[i].name; i++)
125 if (log_facilities[i].val == facility)
126 return log_facilities[i].name;
127 return NULL;
128 }
129
130 LogLevel
log_level_number(char * name)131 log_level_number(char *name)
132 {
133 int i;
134
135 if (name != NULL)
136 for (i = 0; log_levels[i].name; i++)
137 if (strcasecmp(log_levels[i].name, name) == 0)
138 return log_levels[i].val;
139 return SYSLOG_LEVEL_NOT_SET;
140 }
141
142 const char *
log_level_name(LogLevel level)143 log_level_name(LogLevel level)
144 {
145 u_int i;
146
147 for (i = 0; log_levels[i].name != NULL; i++)
148 if (log_levels[i].val == level)
149 return log_levels[i].name;
150 return NULL;
151 }
152
153 /* Error messages that should be logged. */
154
155 void
error(const char * fmt,...)156 error(const char *fmt,...)
157 {
158 va_list args;
159
160 va_start(args, fmt);
161 do_log(SYSLOG_LEVEL_ERROR, fmt, args);
162 va_end(args);
163 }
164
165 void
sigdie(const char * fmt,...)166 sigdie(const char *fmt,...)
167 {
168 #ifdef DO_LOG_SAFE_IN_SIGHAND
169 va_list args;
170
171 va_start(args, fmt);
172 do_log(SYSLOG_LEVEL_FATAL, fmt, args);
173 va_end(args);
174 #endif
175 _exit(1);
176 }
177
178
179 /* Log this message (information that usually should go to the log). */
180
181 void
logit(const char * fmt,...)182 logit(const char *fmt,...)
183 {
184 va_list args;
185
186 va_start(args, fmt);
187 do_log(SYSLOG_LEVEL_INFO, fmt, args);
188 va_end(args);
189 }
190
191 /* More detailed messages (information that does not need to go to the log). */
192
193 void
verbose(const char * fmt,...)194 verbose(const char *fmt,...)
195 {
196 va_list args;
197
198 va_start(args, fmt);
199 do_log(SYSLOG_LEVEL_VERBOSE, fmt, args);
200 va_end(args);
201 }
202
203 /* Debugging messages that should not be logged during normal operation. */
204
205 void
debug(const char * fmt,...)206 debug(const char *fmt,...)
207 {
208 va_list args;
209
210 va_start(args, fmt);
211 do_log(SYSLOG_LEVEL_DEBUG1, fmt, args);
212 va_end(args);
213 }
214
215 void
debug2(const char * fmt,...)216 debug2(const char *fmt,...)
217 {
218 va_list args;
219
220 va_start(args, fmt);
221 do_log(SYSLOG_LEVEL_DEBUG2, fmt, args);
222 va_end(args);
223 }
224
225 void
debug3(const char * fmt,...)226 debug3(const char *fmt,...)
227 {
228 va_list args;
229
230 va_start(args, fmt);
231 do_log(SYSLOG_LEVEL_DEBUG3, fmt, args);
232 va_end(args);
233 }
234
235 /*
236 * Initialize the log.
237 */
238
239 void
log_init(char * av0,LogLevel level,SyslogFacility facility,int on_stderr)240 log_init(char *av0, LogLevel level, SyslogFacility facility, int on_stderr)
241 {
242 #if defined(HAVE_OPENLOG_R) && defined(SYSLOG_DATA_INIT)
243 struct syslog_data sdata = SYSLOG_DATA_INIT;
244 #endif
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 #ifdef LOG_AUTHPRIV
283 case SYSLOG_FACILITY_AUTHPRIV:
284 log_facility = LOG_AUTHPRIV;
285 break;
286 #endif
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 * If an external library (eg libwrap) attempts to use syslog
320 * immediately after reexec, syslog may be pointing to the wrong
321 * facility, so we force an open/close of syslog here.
322 */
323 #if defined(HAVE_OPENLOG_R) && defined(SYSLOG_DATA_INIT)
324 openlog_r(argv0 ? argv0 : __progname, LOG_PID, log_facility, &sdata);
325 closelog_r(&sdata);
326 #else
327 openlog(argv0 ? argv0 : __progname, LOG_PID, log_facility);
328 closelog();
329 #endif
330 }
331
332 #define MSGBUFSIZ 1024
333
334 void
set_log_handler(log_handler_fn * handler,void * ctx)335 set_log_handler(log_handler_fn *handler, void *ctx)
336 {
337 log_handler = handler;
338 log_handler_ctx = ctx;
339 }
340
341 void
do_log2(LogLevel level,const char * fmt,...)342 do_log2(LogLevel level, const char *fmt,...)
343 {
344 va_list args;
345
346 va_start(args, fmt);
347 do_log(level, fmt, args);
348 va_end(args);
349 }
350
351 void
do_log(LogLevel level,const char * fmt,va_list args)352 do_log(LogLevel level, const char *fmt, va_list args)
353 {
354 #if defined(HAVE_OPENLOG_R) && defined(SYSLOG_DATA_INIT)
355 struct syslog_data sdata = SYSLOG_DATA_INIT;
356 #endif
357 char msgbuf[MSGBUFSIZ];
358 char fmtbuf[MSGBUFSIZ];
359 char *txt = NULL;
360 int pri = LOG_INFO;
361 int saved_errno = errno;
362 log_handler_fn *tmp_handler;
363
364 if (level > log_level)
365 return;
366
367 switch (level) {
368 case SYSLOG_LEVEL_FATAL:
369 if (!log_on_stderr)
370 txt = "fatal";
371 pri = LOG_CRIT;
372 break;
373 case SYSLOG_LEVEL_ERROR:
374 if (!log_on_stderr)
375 txt = "error";
376 pri = LOG_ERR;
377 break;
378 case SYSLOG_LEVEL_INFO:
379 pri = LOG_INFO;
380 break;
381 case SYSLOG_LEVEL_VERBOSE:
382 pri = LOG_INFO;
383 break;
384 case SYSLOG_LEVEL_DEBUG1:
385 txt = "debug1";
386 pri = LOG_DEBUG;
387 break;
388 case SYSLOG_LEVEL_DEBUG2:
389 txt = "debug2";
390 pri = LOG_DEBUG;
391 break;
392 case SYSLOG_LEVEL_DEBUG3:
393 txt = "debug3";
394 pri = LOG_DEBUG;
395 break;
396 default:
397 txt = "internal error";
398 pri = LOG_ERR;
399 break;
400 }
401 if (txt != NULL && log_handler == NULL) {
402 snprintf(fmtbuf, sizeof(fmtbuf), "%s: %s", txt, fmt);
403 vsnprintf(msgbuf, sizeof(msgbuf), fmtbuf, args);
404 } else {
405 vsnprintf(msgbuf, sizeof(msgbuf), fmt, args);
406 }
407 strnvis(fmtbuf, msgbuf, sizeof(fmtbuf),
408 log_on_stderr ? LOG_STDERR_VIS : LOG_SYSLOG_VIS);
409 if (log_handler != NULL) {
410 /* Avoid recursion */
411 tmp_handler = log_handler;
412 log_handler = NULL;
413 tmp_handler(level, fmtbuf, log_handler_ctx);
414 log_handler = tmp_handler;
415 } else if (log_on_stderr) {
416 snprintf(msgbuf, sizeof msgbuf, "%s\r\n", fmtbuf);
417 write(STDERR_FILENO, msgbuf, strlen(msgbuf));
418 } else {
419 #if defined(HAVE_OPENLOG_R) && defined(SYSLOG_DATA_INIT)
420 openlog_r(argv0 ? argv0 : __progname, LOG_PID, log_facility, &sdata);
421 syslog_r(pri, &sdata, "%.500s", fmtbuf);
422 closelog_r(&sdata);
423 #else
424 openlog(argv0 ? argv0 : __progname, LOG_PID, log_facility);
425 syslog(pri, "%.500s", fmtbuf);
426 closelog();
427 #endif
428 }
429 errno = saved_errno;
430 }
431