1 /* $OpenBSD: log.c,v 1.43 2012/09/06 04:37:39 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 <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) && !defined(BROKEN_STRNVIS) 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 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 * 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 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 * 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 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 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 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 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 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 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 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 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 void 333 log_change_level(LogLevel new_log_level) 334 { 335 /* no-op if log_init has not been called */ 336 if (argv0 == NULL) 337 return; 338 log_init(argv0, new_log_level, log_facility, log_on_stderr); 339 } 340 341 int 342 log_is_on_stderr(void) 343 { 344 return log_on_stderr; 345 } 346 347 #define MSGBUFSIZ 1024 348 349 void 350 set_log_handler(log_handler_fn *handler, void *ctx) 351 { 352 log_handler = handler; 353 log_handler_ctx = ctx; 354 } 355 356 void 357 do_log2(LogLevel level, const char *fmt,...) 358 { 359 va_list args; 360 361 va_start(args, fmt); 362 do_log(level, fmt, args); 363 va_end(args); 364 } 365 366 void 367 do_log(LogLevel level, const char *fmt, va_list args) 368 { 369 #if defined(HAVE_OPENLOG_R) && defined(SYSLOG_DATA_INIT) 370 struct syslog_data sdata = SYSLOG_DATA_INIT; 371 #endif 372 char msgbuf[MSGBUFSIZ]; 373 char fmtbuf[MSGBUFSIZ]; 374 char *txt = NULL; 375 int pri = LOG_INFO; 376 int saved_errno = errno; 377 log_handler_fn *tmp_handler; 378 379 if (level > log_level) 380 return; 381 382 switch (level) { 383 case SYSLOG_LEVEL_FATAL: 384 if (!log_on_stderr) 385 txt = "fatal"; 386 pri = LOG_CRIT; 387 break; 388 case SYSLOG_LEVEL_ERROR: 389 if (!log_on_stderr) 390 txt = "error"; 391 pri = LOG_ERR; 392 break; 393 case SYSLOG_LEVEL_INFO: 394 pri = LOG_INFO; 395 break; 396 case SYSLOG_LEVEL_VERBOSE: 397 pri = LOG_INFO; 398 break; 399 case SYSLOG_LEVEL_DEBUG1: 400 txt = "debug1"; 401 pri = LOG_DEBUG; 402 break; 403 case SYSLOG_LEVEL_DEBUG2: 404 txt = "debug2"; 405 pri = LOG_DEBUG; 406 break; 407 case SYSLOG_LEVEL_DEBUG3: 408 txt = "debug3"; 409 pri = LOG_DEBUG; 410 break; 411 default: 412 txt = "internal error"; 413 pri = LOG_ERR; 414 break; 415 } 416 if (txt != NULL && log_handler == NULL) { 417 snprintf(fmtbuf, sizeof(fmtbuf), "%s: %s", txt, fmt); 418 vsnprintf(msgbuf, sizeof(msgbuf), fmtbuf, args); 419 } else { 420 vsnprintf(msgbuf, sizeof(msgbuf), fmt, args); 421 } 422 strnvis(fmtbuf, msgbuf, sizeof(fmtbuf), 423 log_on_stderr ? LOG_STDERR_VIS : LOG_SYSLOG_VIS); 424 if (log_handler != NULL) { 425 /* Avoid recursion */ 426 tmp_handler = log_handler; 427 log_handler = NULL; 428 tmp_handler(level, fmtbuf, log_handler_ctx); 429 log_handler = tmp_handler; 430 } else if (log_on_stderr) { 431 snprintf(msgbuf, sizeof msgbuf, "%s\r\n", fmtbuf); 432 write(STDERR_FILENO, msgbuf, strlen(msgbuf)); 433 } else { 434 #if defined(HAVE_OPENLOG_R) && defined(SYSLOG_DATA_INIT) 435 openlog_r(argv0 ? argv0 : __progname, LOG_PID, log_facility, &sdata); 436 syslog_r(pri, &sdata, "%.500s", fmtbuf); 437 closelog_r(&sdata); 438 #else 439 openlog(argv0 ? argv0 : __progname, LOG_PID, log_facility); 440 syslog(pri, "%.500s", fmtbuf); 441 closelog(); 442 #endif 443 } 444 errno = saved_errno; 445 } 446