1 /* $NetBSD: log.c,v 1.26 2022/12/01 22:57:37 christos Exp $ */
2 /* $OpenBSD: log.c,v 1.60 2021/09/16 15:11:19 djm Exp $ */
3
4 /*
5 * Author: Tatu Ylonen <ylo@cs.hut.fi>
6 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
7 * All rights reserved
8 *
9 * As far as I am concerned, the code I have written for this software
10 * can be used freely for any purpose. Any derived versions of this
11 * software must be clearly marked as such, and if the derived work is
12 * incompatible with the protocol description in the RFC file, it must be
13 * called by a name other than "ssh" or "Secure Shell".
14 */
15 /*
16 * Copyright (c) 2000 Markus Friedl. All rights reserved.
17 *
18 * Redistribution and use in source and binary forms, with or without
19 * modification, are permitted provided that the following conditions
20 * are met:
21 * 1. Redistributions of source code must retain the above copyright
22 * notice, this list of conditions and the following disclaimer.
23 * 2. Redistributions in binary form must reproduce the above copyright
24 * notice, this list of conditions and the following disclaimer in the
25 * documentation and/or other materials provided with the distribution.
26 *
27 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
28 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
29 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
30 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
31 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
32 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
33 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
34 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
35 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
36 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
37 */
38
39 #include "includes.h"
40 __RCSID("$NetBSD: log.c,v 1.26 2022/12/01 22:57:37 christos Exp $");
41 #include <sys/types.h>
42 #include <sys/uio.h>
43
44 #include <fcntl.h>
45 #include <stdarg.h>
46 #include <stdio.h>
47 #include <stdlib.h>
48 #include <string.h>
49 #include <syslog.h>
50 #include <unistd.h>
51 #include <errno.h>
52 #include <vis.h>
53
54 #include "log.h"
55 #include "match.h"
56
57 static LogLevel log_level = SYSLOG_LEVEL_INFO;
58 static int log_on_stderr = 1;
59 static int log_stderr_fd = STDERR_FILENO;
60 static int log_facility = LOG_AUTH;
61 static const char *argv0;
62 static log_handler_fn *log_handler;
63 static void *log_handler_ctx;
64 static char **log_verbose;
65 static size_t nlog_verbose;
66 extern char *__progname;
67
68 /* textual representation of log-facilities/levels */
69
70 static struct {
71 const char *name;
72 SyslogFacility val;
73 } log_facilities[] = {
74 { "DAEMON", SYSLOG_FACILITY_DAEMON },
75 { "USER", SYSLOG_FACILITY_USER },
76 { "AUTH", SYSLOG_FACILITY_AUTH },
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 LogLevel
log_level_get(void)106 log_level_get(void)
107 {
108 return log_level;
109 }
110
111 SyslogFacility
log_facility_number(char * name)112 log_facility_number(char *name)
113 {
114 int i;
115
116 if (name != NULL)
117 for (i = 0; log_facilities[i].name; i++)
118 if (strcasecmp(log_facilities[i].name, name) == 0)
119 return log_facilities[i].val;
120 return SYSLOG_FACILITY_NOT_SET;
121 }
122
123 const char *
log_facility_name(SyslogFacility facility)124 log_facility_name(SyslogFacility facility)
125 {
126 u_int i;
127
128 for (i = 0; log_facilities[i].name; i++)
129 if (log_facilities[i].val == facility)
130 return log_facilities[i].name;
131 return NULL;
132 }
133
134 LogLevel
log_level_number(char * name)135 log_level_number(char *name)
136 {
137 int i;
138
139 if (name != NULL)
140 for (i = 0; log_levels[i].name; i++)
141 if (strcasecmp(log_levels[i].name, name) == 0)
142 return log_levels[i].val;
143 return SYSLOG_LEVEL_NOT_SET;
144 }
145
146 const char *
log_level_name(LogLevel level)147 log_level_name(LogLevel level)
148 {
149 u_int i;
150
151 for (i = 0; log_levels[i].name != NULL; i++)
152 if (log_levels[i].val == level)
153 return log_levels[i].name;
154 return NULL;
155 }
156
157 void
log_verbose_add(const char * s)158 log_verbose_add(const char *s)
159 {
160 char **tmp;
161
162 /* Ignore failures here */
163 if ((tmp = recallocarray(log_verbose, nlog_verbose, nlog_verbose + 1,
164 sizeof(*log_verbose))) != NULL) {
165 log_verbose = tmp;
166 if ((log_verbose[nlog_verbose] = strdup(s)) != NULL)
167 nlog_verbose++;
168 }
169 }
170
171 void
log_verbose_reset(void)172 log_verbose_reset(void)
173 {
174 size_t i;
175
176 for (i = 0; i < nlog_verbose; i++)
177 free(log_verbose[i]);
178 free(log_verbose);
179 log_verbose = NULL;
180 nlog_verbose = 0;
181 }
182
183 /*
184 * Initialize the log.
185 */
186
187 void
log_init(const char * av0,LogLevel level,SyslogFacility facility,int on_stderr)188 log_init(const char *av0, LogLevel level, SyslogFacility facility,
189 int on_stderr)
190 {
191 argv0 = av0;
192
193 if (log_change_level(level) != 0) {
194 fprintf(stderr, "Unrecognized internal syslog level code %d\n",
195 (int) level);
196 exit(1);
197 }
198
199 log_handler = NULL;
200 log_handler_ctx = NULL;
201
202 log_on_stderr = on_stderr;
203 if (on_stderr)
204 return;
205
206 switch (facility) {
207 case SYSLOG_FACILITY_DAEMON:
208 log_facility = LOG_DAEMON;
209 break;
210 case SYSLOG_FACILITY_USER:
211 log_facility = LOG_USER;
212 break;
213 case SYSLOG_FACILITY_AUTH:
214 log_facility = LOG_AUTH;
215 break;
216 case SYSLOG_FACILITY_LOCAL0:
217 log_facility = LOG_LOCAL0;
218 break;
219 case SYSLOG_FACILITY_LOCAL1:
220 log_facility = LOG_LOCAL1;
221 break;
222 case SYSLOG_FACILITY_LOCAL2:
223 log_facility = LOG_LOCAL2;
224 break;
225 case SYSLOG_FACILITY_LOCAL3:
226 log_facility = LOG_LOCAL3;
227 break;
228 case SYSLOG_FACILITY_LOCAL4:
229 log_facility = LOG_LOCAL4;
230 break;
231 case SYSLOG_FACILITY_LOCAL5:
232 log_facility = LOG_LOCAL5;
233 break;
234 case SYSLOG_FACILITY_LOCAL6:
235 log_facility = LOG_LOCAL6;
236 break;
237 case SYSLOG_FACILITY_LOCAL7:
238 log_facility = LOG_LOCAL7;
239 break;
240 default:
241 fprintf(stderr,
242 "Unrecognized internal syslog facility code %d\n",
243 (int) facility);
244 exit(1);
245 }
246 }
247
248 int
log_change_level(LogLevel new_log_level)249 log_change_level(LogLevel new_log_level)
250 {
251 /* no-op if log_init has not been called */
252 if (argv0 == NULL)
253 return 0;
254
255 switch (new_log_level) {
256 case SYSLOG_LEVEL_QUIET:
257 case SYSLOG_LEVEL_FATAL:
258 case SYSLOG_LEVEL_ERROR:
259 case SYSLOG_LEVEL_INFO:
260 case SYSLOG_LEVEL_VERBOSE:
261 case SYSLOG_LEVEL_DEBUG1:
262 case SYSLOG_LEVEL_DEBUG2:
263 case SYSLOG_LEVEL_DEBUG3:
264 log_level = new_log_level;
265 return 0;
266 default:
267 return -1;
268 }
269 }
270
271 int
log_is_on_stderr(void)272 log_is_on_stderr(void)
273 {
274 return log_on_stderr && log_stderr_fd == STDERR_FILENO;
275 }
276
277 /* redirect what would usually get written to stderr to specified file */
278 void
log_redirect_stderr_to(const char * logfile)279 log_redirect_stderr_to(const char *logfile)
280 {
281 int fd;
282
283 if (logfile == NULL) {
284 if (log_stderr_fd != STDERR_FILENO) {
285 close(log_stderr_fd);
286 log_stderr_fd = STDERR_FILENO;
287 }
288 return;
289 }
290
291 if ((fd = open(logfile, O_WRONLY|O_CREAT|O_APPEND, 0600)) == -1) {
292 fprintf(stderr, "Couldn't open logfile %s: %s\n", logfile,
293 strerror(errno));
294 exit(1);
295 }
296 log_stderr_fd = fd;
297 }
298
299 #define MSGBUFSIZ 1024
300
301 void
set_log_handler(log_handler_fn * handler,void * ctx)302 set_log_handler(log_handler_fn *handler, void *ctx)
303 {
304 log_handler = handler;
305 log_handler_ctx = ctx;
306 }
307
308 static void
do_log(LogLevel level,int force,const char * suffix,const char * fmt,va_list args)309 do_log(LogLevel level, int force, const char *suffix, const char *fmt,
310 va_list args)
311 {
312 #ifdef SYSLOG_DATA_INIT
313 struct syslog_data sdata = SYSLOG_DATA_INIT;
314 #endif
315 char msgbuf[MSGBUFSIZ], *msgbufp;
316 char visbuf[MSGBUFSIZ * 4 + 1];
317 size_t len, len2;
318 const char *txt = NULL;
319 int pri = LOG_INFO;
320 int saved_errno = errno;
321 log_handler_fn *tmp_handler;
322 const char *progname = argv0 != NULL ? argv0 : __progname;
323
324 if (!force && level > log_level)
325 return;
326
327 switch (level) {
328 case SYSLOG_LEVEL_FATAL:
329 if (!log_on_stderr)
330 txt = "fatal";
331 pri = LOG_CRIT;
332 break;
333 case SYSLOG_LEVEL_ERROR:
334 if (!log_on_stderr)
335 txt = "error";
336 pri = LOG_ERR;
337 break;
338 case SYSLOG_LEVEL_INFO:
339 pri = LOG_INFO;
340 break;
341 case SYSLOG_LEVEL_VERBOSE:
342 pri = LOG_INFO;
343 break;
344 case SYSLOG_LEVEL_DEBUG1:
345 txt = "debug1";
346 pri = LOG_DEBUG;
347 break;
348 case SYSLOG_LEVEL_DEBUG2:
349 txt = "debug2";
350 pri = LOG_DEBUG;
351 break;
352 case SYSLOG_LEVEL_DEBUG3:
353 txt = "debug3";
354 pri = LOG_DEBUG;
355 break;
356 default:
357 txt = "internal error";
358 pri = LOG_ERR;
359 break;
360 }
361 len = sizeof(msgbuf);
362 msgbufp = msgbuf;
363 if (txt != NULL && log_handler == NULL) {
364 len2 = strlen(txt);
365 if (len2 > len - 2)
366 len2 = len - 2;
367 memcpy(msgbufp, txt, len2);
368 msgbufp += len2;
369 *msgbufp++ = ':';
370 *msgbufp++ = ' ';
371 len -= len2 + 2;
372 }
373 vsnprintf(msgbufp, len, fmt, args);
374 if (suffix != NULL) {
375 snprintf(visbuf, sizeof(visbuf), "%s: %s", msgbuf, suffix);
376 strlcpy(msgbuf, visbuf, sizeof(msgbuf));
377 }
378 strnvis(visbuf, sizeof(visbuf), msgbuf, VIS_SAFE|VIS_OCTAL);
379 if (log_handler != NULL) {
380 /* Avoid recursion */
381 tmp_handler = log_handler;
382 log_handler = NULL;
383 tmp_handler(level, force, visbuf, log_handler_ctx);
384 log_handler = tmp_handler;
385 } else if (log_on_stderr) {
386 snprintf(msgbuf, sizeof msgbuf, "%s%s%.*s\r\n",
387 (log_on_stderr > 1) ? progname : "",
388 (log_on_stderr > 1) ? ": " : "",
389 (int)sizeof msgbuf - 10, visbuf);
390 (void)write(log_stderr_fd, msgbuf, strlen(msgbuf));
391 } else {
392 #ifdef SYSLOG_DATA_INIT
393 openlog_r(progname, LOG_PID, log_facility, &sdata);
394 syslog_r(pri, &sdata, "%.500s", visbuf);
395 closelog_r(&sdata);
396 #else
397 openlog(progname, LOG_PID, log_facility);
398 syslog(pri, "%.500s", visbuf);
399 closelog();
400 #endif
401 }
402 errno = saved_errno;
403 }
404
405 void
sshlog(const char * file,const char * func,int line,int showfunc,LogLevel level,const char * suffix,const char * fmt,...)406 sshlog(const char *file, const char *func, int line, int showfunc,
407 LogLevel level, const char *suffix, const char *fmt, ...)
408 {
409 va_list args;
410
411 va_start(args, fmt);
412 sshlogv(file, func, line, showfunc, level, suffix, fmt, args);
413 va_end(args);
414 }
415
416 void
sshlogdie(const char * file,const char * func,int line,int showfunc,LogLevel level,const char * suffix,const char * fmt,...)417 sshlogdie(const char *file, const char *func, int line, int showfunc,
418 LogLevel level, const char *suffix, const char *fmt, ...)
419 {
420 va_list args;
421
422 va_start(args, fmt);
423 sshlogv(file, func, line, showfunc, SYSLOG_LEVEL_INFO,
424 suffix, fmt, args);
425 va_end(args);
426 cleanup_exit(254);
427 }
428
429 void
sshsigdie(const char * file,const char * func,int line,int showfunc,LogLevel level,const char * suffix,const char * fmt,...)430 sshsigdie(const char *file, const char *func, int line, int showfunc,
431 LogLevel level, const char *suffix, const char *fmt, ...)
432 {
433 va_list args;
434
435 va_start(args, fmt);
436 sshlogv(file, func, line, showfunc, SYSLOG_LEVEL_FATAL,
437 suffix, fmt, args);
438 va_end(args);
439 _exit(1);
440 }
441
442 void
sshlogv(const char * file,const char * func,int line,int showfunc,LogLevel level,const char * suffix,const char * fmt,va_list args)443 sshlogv(const char *file, const char *func, int line, int showfunc,
444 LogLevel level, const char *suffix, const char *fmt, va_list args)
445 {
446 char tag[128], fmt2[MSGBUFSIZ + 128];
447 int forced = 0;
448 const char *cp;
449 size_t i;
450
451 snprintf(tag, sizeof(tag), "%.48s:%.48s():%d (pid=%ld)",
452 (cp = strrchr(file, '/')) == NULL ? file : cp + 1, func, line,
453 (long)getpid());
454 for (i = 0; i < nlog_verbose; i++) {
455 if (match_pattern_list(tag, log_verbose[i], 0) == 1) {
456 forced = 1;
457 break;
458 }
459 }
460
461 if (forced)
462 snprintf(fmt2, sizeof(fmt2), "%s: %s", tag, fmt);
463 else if (showfunc)
464 snprintf(fmt2, sizeof(fmt2), "%s: %s", func, fmt);
465 else
466 strlcpy(fmt2, fmt, sizeof(fmt2));
467
468 do_log(level, forced, suffix, fmt2, args);
469 }
470
471 void
sshlogdirect(LogLevel level,int forced,const char * fmt,...)472 sshlogdirect(LogLevel level, int forced, const char *fmt, ...)
473 {
474 va_list args;
475
476 va_start(args, fmt);
477 do_log(level, forced, NULL, fmt, args);
478 va_end(args);
479 }
480