1 /* $OpenBSD: log.c,v 1.45 2013/05/16 09:08:41 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 <fcntl.h> 42 #include <stdarg.h> 43 #include <stdio.h> 44 #include <stdlib.h> 45 #include <string.h> 46 #include <syslog.h> 47 #include <unistd.h> 48 #include <errno.h> 49 #if defined(HAVE_STRNVIS) && defined(HAVE_VIS_H) && !defined(BROKEN_STRNVIS) 50 # include <vis.h> 51 #endif 52 53 #include "xmalloc.h" 54 #include "log.h" 55 56 static LogLevel log_level = SYSLOG_LEVEL_INFO; 57 static int log_on_stderr = 1; 58 static int log_stderr_fd = STDERR_FILENO; 59 static int log_facility = LOG_AUTH; 60 static char *argv0; 61 static log_handler_fn *log_handler; 62 static void *log_handler_ctx; 63 64 extern char *__progname; 65 66 #define LOG_SYSLOG_VIS (VIS_CSTYLE|VIS_NL|VIS_TAB|VIS_OCTAL) 67 #define LOG_STDERR_VIS (VIS_SAFE|VIS_OCTAL) 68 69 /* textual representation of log-facilities/levels */ 70 71 static struct { 72 const char *name; 73 SyslogFacility val; 74 } log_facilities[] = { 75 { "DAEMON", SYSLOG_FACILITY_DAEMON }, 76 { "USER", SYSLOG_FACILITY_USER }, 77 { "AUTH", SYSLOG_FACILITY_AUTH }, 78 #ifdef LOG_AUTHPRIV 79 { "AUTHPRIV", SYSLOG_FACILITY_AUTHPRIV }, 80 #endif 81 { "LOCAL0", SYSLOG_FACILITY_LOCAL0 }, 82 { "LOCAL1", SYSLOG_FACILITY_LOCAL1 }, 83 { "LOCAL2", SYSLOG_FACILITY_LOCAL2 }, 84 { "LOCAL3", SYSLOG_FACILITY_LOCAL3 }, 85 { "LOCAL4", SYSLOG_FACILITY_LOCAL4 }, 86 { "LOCAL5", SYSLOG_FACILITY_LOCAL5 }, 87 { "LOCAL6", SYSLOG_FACILITY_LOCAL6 }, 88 { "LOCAL7", SYSLOG_FACILITY_LOCAL7 }, 89 { NULL, SYSLOG_FACILITY_NOT_SET } 90 }; 91 92 static struct { 93 const char *name; 94 LogLevel val; 95 } log_levels[] = 96 { 97 { "QUIET", SYSLOG_LEVEL_QUIET }, 98 { "FATAL", SYSLOG_LEVEL_FATAL }, 99 { "ERROR", SYSLOG_LEVEL_ERROR }, 100 { "INFO", SYSLOG_LEVEL_INFO }, 101 { "VERBOSE", SYSLOG_LEVEL_VERBOSE }, 102 { "DEBUG", SYSLOG_LEVEL_DEBUG1 }, 103 { "DEBUG1", SYSLOG_LEVEL_DEBUG1 }, 104 { "DEBUG2", SYSLOG_LEVEL_DEBUG2 }, 105 { "DEBUG3", SYSLOG_LEVEL_DEBUG3 }, 106 { NULL, SYSLOG_LEVEL_NOT_SET } 107 }; 108 109 SyslogFacility 110 log_facility_number(char *name) 111 { 112 int i; 113 114 if (name != NULL) 115 for (i = 0; log_facilities[i].name; i++) 116 if (strcasecmp(log_facilities[i].name, name) == 0) 117 return log_facilities[i].val; 118 return SYSLOG_FACILITY_NOT_SET; 119 } 120 121 const char * 122 log_facility_name(SyslogFacility facility) 123 { 124 u_int i; 125 126 for (i = 0; log_facilities[i].name; i++) 127 if (log_facilities[i].val == facility) 128 return log_facilities[i].name; 129 return NULL; 130 } 131 132 LogLevel 133 log_level_number(char *name) 134 { 135 int i; 136 137 if (name != NULL) 138 for (i = 0; log_levels[i].name; i++) 139 if (strcasecmp(log_levels[i].name, name) == 0) 140 return log_levels[i].val; 141 return SYSLOG_LEVEL_NOT_SET; 142 } 143 144 const char * 145 log_level_name(LogLevel level) 146 { 147 u_int i; 148 149 for (i = 0; log_levels[i].name != NULL; i++) 150 if (log_levels[i].val == level) 151 return log_levels[i].name; 152 return NULL; 153 } 154 155 /* Error messages that should be logged. */ 156 157 void 158 error(const char *fmt,...) 159 { 160 va_list args; 161 162 va_start(args, fmt); 163 do_log(SYSLOG_LEVEL_ERROR, fmt, args); 164 va_end(args); 165 } 166 167 void 168 sigdie(const char *fmt,...) 169 { 170 #ifdef DO_LOG_SAFE_IN_SIGHAND 171 va_list args; 172 173 va_start(args, fmt); 174 do_log(SYSLOG_LEVEL_FATAL, fmt, args); 175 va_end(args); 176 #endif 177 _exit(1); 178 } 179 180 181 /* Log this message (information that usually should go to the log). */ 182 183 void 184 logit(const char *fmt,...) 185 { 186 va_list args; 187 188 va_start(args, fmt); 189 do_log(SYSLOG_LEVEL_INFO, fmt, args); 190 va_end(args); 191 } 192 193 /* More detailed messages (information that does not need to go to the log). */ 194 195 void 196 verbose(const char *fmt,...) 197 { 198 va_list args; 199 200 va_start(args, fmt); 201 do_log(SYSLOG_LEVEL_VERBOSE, fmt, args); 202 va_end(args); 203 } 204 205 /* Debugging messages that should not be logged during normal operation. */ 206 207 void 208 debug(const char *fmt,...) 209 { 210 va_list args; 211 212 va_start(args, fmt); 213 do_log(SYSLOG_LEVEL_DEBUG1, fmt, args); 214 va_end(args); 215 } 216 217 void 218 debug2(const char *fmt,...) 219 { 220 va_list args; 221 222 va_start(args, fmt); 223 do_log(SYSLOG_LEVEL_DEBUG2, fmt, args); 224 va_end(args); 225 } 226 227 void 228 debug3(const char *fmt,...) 229 { 230 va_list args; 231 232 va_start(args, fmt); 233 do_log(SYSLOG_LEVEL_DEBUG3, fmt, args); 234 va_end(args); 235 } 236 237 /* 238 * Initialize the log. 239 */ 240 241 void 242 log_init(char *av0, LogLevel level, SyslogFacility facility, int on_stderr) 243 { 244 #if defined(HAVE_OPENLOG_R) && defined(SYSLOG_DATA_INIT) 245 struct syslog_data sdata = SYSLOG_DATA_INIT; 246 #endif 247 248 argv0 = av0; 249 250 switch (level) { 251 case SYSLOG_LEVEL_QUIET: 252 case SYSLOG_LEVEL_FATAL: 253 case SYSLOG_LEVEL_ERROR: 254 case SYSLOG_LEVEL_INFO: 255 case SYSLOG_LEVEL_VERBOSE: 256 case SYSLOG_LEVEL_DEBUG1: 257 case SYSLOG_LEVEL_DEBUG2: 258 case SYSLOG_LEVEL_DEBUG3: 259 log_level = level; 260 break; 261 default: 262 fprintf(stderr, "Unrecognized internal syslog level code %d\n", 263 (int) level); 264 exit(1); 265 } 266 267 log_handler = NULL; 268 log_handler_ctx = NULL; 269 270 log_on_stderr = on_stderr; 271 if (on_stderr) 272 return; 273 274 switch (facility) { 275 case SYSLOG_FACILITY_DAEMON: 276 log_facility = LOG_DAEMON; 277 break; 278 case SYSLOG_FACILITY_USER: 279 log_facility = LOG_USER; 280 break; 281 case SYSLOG_FACILITY_AUTH: 282 log_facility = LOG_AUTH; 283 break; 284 #ifdef LOG_AUTHPRIV 285 case SYSLOG_FACILITY_AUTHPRIV: 286 log_facility = LOG_AUTHPRIV; 287 break; 288 #endif 289 case SYSLOG_FACILITY_LOCAL0: 290 log_facility = LOG_LOCAL0; 291 break; 292 case SYSLOG_FACILITY_LOCAL1: 293 log_facility = LOG_LOCAL1; 294 break; 295 case SYSLOG_FACILITY_LOCAL2: 296 log_facility = LOG_LOCAL2; 297 break; 298 case SYSLOG_FACILITY_LOCAL3: 299 log_facility = LOG_LOCAL3; 300 break; 301 case SYSLOG_FACILITY_LOCAL4: 302 log_facility = LOG_LOCAL4; 303 break; 304 case SYSLOG_FACILITY_LOCAL5: 305 log_facility = LOG_LOCAL5; 306 break; 307 case SYSLOG_FACILITY_LOCAL6: 308 log_facility = LOG_LOCAL6; 309 break; 310 case SYSLOG_FACILITY_LOCAL7: 311 log_facility = LOG_LOCAL7; 312 break; 313 default: 314 fprintf(stderr, 315 "Unrecognized internal syslog facility code %d\n", 316 (int) facility); 317 exit(1); 318 } 319 320 /* 321 * If an external library (eg libwrap) attempts to use syslog 322 * immediately after reexec, syslog may be pointing to the wrong 323 * facility, so we force an open/close of syslog here. 324 */ 325 #if defined(HAVE_OPENLOG_R) && defined(SYSLOG_DATA_INIT) 326 openlog_r(argv0 ? argv0 : __progname, LOG_PID, log_facility, &sdata); 327 closelog_r(&sdata); 328 #else 329 openlog(argv0 ? argv0 : __progname, LOG_PID, log_facility); 330 closelog(); 331 #endif 332 } 333 334 void 335 log_change_level(LogLevel new_log_level) 336 { 337 /* no-op if log_init has not been called */ 338 if (argv0 == NULL) 339 return; 340 log_init(argv0, new_log_level, log_facility, log_on_stderr); 341 } 342 343 int 344 log_is_on_stderr(void) 345 { 346 return log_on_stderr; 347 } 348 349 /* redirect what would usually get written to stderr to specified file */ 350 void 351 log_redirect_stderr_to(const char *logfile) 352 { 353 int fd; 354 355 if ((fd = open(logfile, O_WRONLY|O_CREAT|O_APPEND, 0600)) == -1) { 356 fprintf(stderr, "Couldn't open logfile %s: %s\n", logfile, 357 strerror(errno)); 358 exit(1); 359 } 360 log_stderr_fd = fd; 361 } 362 363 #define MSGBUFSIZ 1024 364 365 void 366 set_log_handler(log_handler_fn *handler, void *ctx) 367 { 368 log_handler = handler; 369 log_handler_ctx = ctx; 370 } 371 372 void 373 do_log2(LogLevel level, const char *fmt,...) 374 { 375 va_list args; 376 377 va_start(args, fmt); 378 do_log(level, fmt, args); 379 va_end(args); 380 } 381 382 void 383 do_log(LogLevel level, const char *fmt, va_list args) 384 { 385 #if defined(HAVE_OPENLOG_R) && defined(SYSLOG_DATA_INIT) 386 struct syslog_data sdata = SYSLOG_DATA_INIT; 387 #endif 388 char msgbuf[MSGBUFSIZ]; 389 char fmtbuf[MSGBUFSIZ]; 390 char *txt = NULL; 391 int pri = LOG_INFO; 392 int saved_errno = errno; 393 log_handler_fn *tmp_handler; 394 395 if (level > log_level) 396 return; 397 398 switch (level) { 399 case SYSLOG_LEVEL_FATAL: 400 if (!log_on_stderr) 401 txt = "fatal"; 402 pri = LOG_CRIT; 403 break; 404 case SYSLOG_LEVEL_ERROR: 405 if (!log_on_stderr) 406 txt = "error"; 407 pri = LOG_ERR; 408 break; 409 case SYSLOG_LEVEL_INFO: 410 pri = LOG_INFO; 411 break; 412 case SYSLOG_LEVEL_VERBOSE: 413 pri = LOG_INFO; 414 break; 415 case SYSLOG_LEVEL_DEBUG1: 416 txt = "debug1"; 417 pri = LOG_DEBUG; 418 break; 419 case SYSLOG_LEVEL_DEBUG2: 420 txt = "debug2"; 421 pri = LOG_DEBUG; 422 break; 423 case SYSLOG_LEVEL_DEBUG3: 424 txt = "debug3"; 425 pri = LOG_DEBUG; 426 break; 427 default: 428 txt = "internal error"; 429 pri = LOG_ERR; 430 break; 431 } 432 if (txt != NULL && log_handler == NULL) { 433 snprintf(fmtbuf, sizeof(fmtbuf), "%s: %s", txt, fmt); 434 vsnprintf(msgbuf, sizeof(msgbuf), fmtbuf, args); 435 } else { 436 vsnprintf(msgbuf, sizeof(msgbuf), fmt, args); 437 } 438 strnvis(fmtbuf, msgbuf, sizeof(fmtbuf), 439 log_on_stderr ? LOG_STDERR_VIS : LOG_SYSLOG_VIS); 440 if (log_handler != NULL) { 441 /* Avoid recursion */ 442 tmp_handler = log_handler; 443 log_handler = NULL; 444 tmp_handler(level, fmtbuf, log_handler_ctx); 445 log_handler = tmp_handler; 446 } else if (log_on_stderr) { 447 snprintf(msgbuf, sizeof msgbuf, "%s\r\n", fmtbuf); 448 (void)write(log_stderr_fd, msgbuf, strlen(msgbuf)); 449 } else { 450 #if defined(HAVE_OPENLOG_R) && defined(SYSLOG_DATA_INIT) 451 openlog_r(argv0 ? argv0 : __progname, LOG_PID, log_facility, &sdata); 452 syslog_r(pri, &sdata, "%.500s", fmtbuf); 453 closelog_r(&sdata); 454 #else 455 openlog(argv0 ? argv0 : __progname, LOG_PID, log_facility); 456 syslog(pri, "%.500s", fmtbuf); 457 closelog(); 458 #endif 459 } 460 errno = saved_errno; 461 } 462