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 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 #define MSGBUFSIZ 1024 333 334 void 335 set_log_handler(log_handler_fn *handler, void *ctx) 336 { 337 log_handler = handler; 338 log_handler_ctx = ctx; 339 } 340 341 void 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 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