log.c

   1 /* $OpenBSD: log.c,v 1.41 2008/06/10 04:50:25 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)
  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
  60 extern char *__progname;
  61
  62 #define LOG_SYSLOG_VIS  (VIS_CSTYLE|VIS_NL|VIS_TAB|VIS_OCTAL)
  63 #define LOG_STDERR_VIS  (VIS_SAFE|VIS_OCTAL)
  64
  65 /* textual representation of log-facilities/levels */
  66
  67 static struct {
  68         const char *name;
  69         SyslogFacility val;
  70 } log_facilities[] = {
  71         { "DAEMON",     SYSLOG_FACILITY_DAEMON },
  72         { "USER",       SYSLOG_FACILITY_USER },
  73         { "AUTH",       SYSLOG_FACILITY_AUTH },
  74 #ifdef LOG_AUTHPRIV
  75         { "AUTHPRIV",   SYSLOG_FACILITY_AUTHPRIV },
  76 #endif
  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 SyslogFacility
 106 log_facility_number(char *name)
 107 {
 108         int i;
 109
 110         if (name != NULL)
 111                 for (i = 0; log_facilities[i].name; i++)
 112                         if (strcasecmp(log_facilities[i].name, name) == 0)
 113                                 return log_facilities[i].val;
 114         return SYSLOG_FACILITY_NOT_SET;
 115 }
 116
 117 const char *
 118 log_facility_name(SyslogFacility facility)
 119 {
 120         u_int i;
 121
 122         for (i = 0;  log_facilities[i].name; i++)
 123                 if (log_facilities[i].val == facility)
 124                         return log_facilities[i].name;
 125         return NULL;
 126 }
 127
 128 LogLevel
 129 log_level_number(char *name)
 130 {
 131         int i;
 132
 133         if (name != NULL)
 134                 for (i = 0; log_levels[i].name; i++)
 135                         if (strcasecmp(log_levels[i].name, name) == 0)
 136                                 return log_levels[i].val;
 137         return SYSLOG_LEVEL_NOT_SET;
 138 }
 139
 140 const char *
 141 log_level_name(LogLevel level)
 142 {
 143         u_int i;
 144
 145         for (i = 0; log_levels[i].name != NULL; i++)
 146                 if (log_levels[i].val == level)
 147                         return log_levels[i].name;
 148         return NULL;
 149 }
 150
 151 /* Error messages that should be logged. */
 152
 153 void
 154 error(const char *fmt,...)
 155 {
 156         va_list args;
 157
 158         va_start(args, fmt);
 159         do_log(SYSLOG_LEVEL_ERROR, fmt, args);
 160         va_end(args);
 161 }
 162
 163 void
 164 sigdie(const char *fmt,...)
 165 {
 166 #ifdef DO_LOG_SAFE_IN_SIGHAND
 167         va_list args;
 168
 169         va_start(args, fmt);
 170         do_log(SYSLOG_LEVEL_FATAL, fmt, args);
 171         va_end(args);
 172 #endif
 173         _exit(1);
 174 }
 175
 176
 177 /* Log this message (information that usually should go to the log). */
 178
 179 void
 180 logit(const char *fmt,...)
 181 {
 182         va_list args;
 183
 184         va_start(args, fmt);
 185         do_log(SYSLOG_LEVEL_INFO, fmt, args);
 186         va_end(args);
 187 }
 188
 189 /* More detailed messages (information that does not need to go to the log). */
 190
 191 void
 192 verbose(const char *fmt,...)
 193 {
 194         va_list args;
 195
 196         va_start(args, fmt);
 197         do_log(SYSLOG_LEVEL_VERBOSE, fmt, args);
 198         va_end(args);
 199 }
 200
 201 /* Debugging messages that should not be logged during normal operation. */
 202
 203 void
 204 debug(const char *fmt,...)
 205 {
 206         va_list args;
 207
 208         va_start(args, fmt);
 209         do_log(SYSLOG_LEVEL_DEBUG1, fmt, args);
 210         va_end(args);
 211 }
 212
 213 void
 214 debug2(const char *fmt,...)
 215 {
 216         va_list args;
 217
 218         va_start(args, fmt);
 219         do_log(SYSLOG_LEVEL_DEBUG2, fmt, args);
 220         va_end(args);
 221 }
 222
 223 void
 224 debug3(const char *fmt,...)
 225 {
 226         va_list args;
 227
 228         va_start(args, fmt);
 229         do_log(SYSLOG_LEVEL_DEBUG3, fmt, args);
 230         va_end(args);
 231 }
 232
 233 /*
 234  * Initialize the log.
 235  */
 236
 237 void
 238 log_init(char *av0, LogLevel level, SyslogFacility facility, int on_stderr)
 239 {
 240 #if defined(HAVE_OPENLOG_R) && defined(SYSLOG_DATA_INIT)
 241         struct syslog_data sdata = SYSLOG_DATA_INIT;
 242 #endif
 243
 244         argv0 = av0;
 245
 246         switch (level) {
 247         case SYSLOG_LEVEL_QUIET:
 248         case SYSLOG_LEVEL_FATAL:
 249         case SYSLOG_LEVEL_ERROR:
 250         case SYSLOG_LEVEL_INFO:
 251         case SYSLOG_LEVEL_VERBOSE:
 252         case SYSLOG_LEVEL_DEBUG1:
 253         case SYSLOG_LEVEL_DEBUG2:
 254         case SYSLOG_LEVEL_DEBUG3:
 255                 log_level = level;
 256                 break;
 257         default:
 258                 fprintf(stderr, "Unrecognized internal syslog level code %d\n",
 259                     (int) level);
 260                 exit(1);
 261         }
 262
 263         log_on_stderr = on_stderr;
 264         if (on_stderr)
 265                 return;
 266
 267         switch (facility) {
 268         case SYSLOG_FACILITY_DAEMON:
 269                 log_facility = LOG_DAEMON;
 270                 break;
 271         case SYSLOG_FACILITY_USER:
 272                 log_facility = LOG_USER;
 273                 break;
 274         case SYSLOG_FACILITY_AUTH:
 275                 log_facility = LOG_AUTH;
 276                 break;
 277 #ifdef LOG_AUTHPRIV
 278         case SYSLOG_FACILITY_AUTHPRIV:
 279                 log_facility = LOG_AUTHPRIV;
 280                 break;
 281 #endif
 282         case SYSLOG_FACILITY_LOCAL0:
 283                 log_facility = LOG_LOCAL0;
 284                 break;
 285         case SYSLOG_FACILITY_LOCAL1:
 286                 log_facility = LOG_LOCAL1;
 287                 break;
 288         case SYSLOG_FACILITY_LOCAL2:
 289                 log_facility = LOG_LOCAL2;
 290                 break;
 291         case SYSLOG_FACILITY_LOCAL3:
 292                 log_facility = LOG_LOCAL3;
 293                 break;
 294         case SYSLOG_FACILITY_LOCAL4:
 295                 log_facility = LOG_LOCAL4;
 296                 break;
 297         case SYSLOG_FACILITY_LOCAL5:
 298                 log_facility = LOG_LOCAL5;
 299                 break;
 300         case SYSLOG_FACILITY_LOCAL6:
 301                 log_facility = LOG_LOCAL6;
 302                 break;
 303         case SYSLOG_FACILITY_LOCAL7:
 304                 log_facility = LOG_LOCAL7;
 305                 break;
 306         default:
 307                 fprintf(stderr,
 308                     "Unrecognized internal syslog facility code %d\n",
 309                     (int) facility);
 310                 exit(1);
 311         }
 312
 313         /*
 314          * If an external library (eg libwrap) attempts to use syslog
 315          * immediately after reexec, syslog may be pointing to the wrong
 316          * facility, so we force an open/close of syslog here.
 317          */
 318 #if defined(HAVE_OPENLOG_R) && defined(SYSLOG_DATA_INIT)
 319         openlog_r(argv0 ? argv0 : __progname, LOG_PID, log_facility, &sdata);
 320         closelog_r(&sdata);
 321 #else
 322         openlog(argv0 ? argv0 : __progname, LOG_PID, log_facility);
 323         closelog();
 324 #endif
 325 }
 326
 327 #define MSGBUFSIZ 1024
 328
 329 void
 330 do_log(LogLevel level, const char *fmt, va_list args)
 331 {
 332 #if defined(HAVE_OPENLOG_R) && defined(SYSLOG_DATA_INIT)
 333         struct syslog_data sdata = SYSLOG_DATA_INIT;
 334 #endif
 335         char msgbuf[MSGBUFSIZ];
 336         char fmtbuf[MSGBUFSIZ];
 337         char *txt = NULL;
 338         int pri = LOG_INFO;
 339         int saved_errno = errno;
 340
 341         if (level > log_level)
 342                 return;
 343
 344         switch (level) {
 345         case SYSLOG_LEVEL_FATAL:
 346                 if (!log_on_stderr)
 347                         txt = "fatal";
 348                 pri = LOG_CRIT;
 349                 break;
 350         case SYSLOG_LEVEL_ERROR:
 351                 if (!log_on_stderr)
 352                         txt = "error";
 353                 pri = LOG_ERR;
 354                 break;
 355         case SYSLOG_LEVEL_INFO:
 356                 pri = LOG_INFO;
 357                 break;
 358         case SYSLOG_LEVEL_VERBOSE:
 359                 pri = LOG_INFO;
 360                 break;
 361         case SYSLOG_LEVEL_DEBUG1:
 362                 txt = "debug1";
 363                 pri = LOG_DEBUG;
 364                 break;
 365         case SYSLOG_LEVEL_DEBUG2:
 366                 txt = "debug2";
 367                 pri = LOG_DEBUG;
 368                 break;
 369         case SYSLOG_LEVEL_DEBUG3:
 370                 txt = "debug3";
 371                 pri = LOG_DEBUG;
 372                 break;
 373         default:
 374                 txt = "internal error";
 375                 pri = LOG_ERR;
 376                 break;
 377         }
 378         if (txt != NULL) {
 379                 snprintf(fmtbuf, sizeof(fmtbuf), "%s: %s", txt, fmt);
 380                 vsnprintf(msgbuf, sizeof(msgbuf), fmtbuf, args);
 381         } else {
 382                 vsnprintf(msgbuf, sizeof(msgbuf), fmt, args);
 383         }
 384         strnvis(fmtbuf, msgbuf, sizeof(fmtbuf),
 385             log_on_stderr ? LOG_STDERR_VIS : LOG_SYSLOG_VIS);
 386         if (log_on_stderr) {
 387                 snprintf(msgbuf, sizeof msgbuf, "%s\r\n", fmtbuf);
 388                 write(STDERR_FILENO, msgbuf, strlen(msgbuf));
 389         } else {
 390 #if defined(HAVE_OPENLOG_R) && defined(SYSLOG_DATA_INIT)
 391                 openlog_r(argv0 ? argv0 : __progname, LOG_PID, log_facility, &sdata);
 392                 syslog_r(pri, &sdata, "%.500s", fmtbuf);
 393                 closelog_r(&sdata);
 394 #else
 395                 openlog(argv0 ? argv0 : __progname, LOG_PID, log_facility);
 396                 syslog(pri, "%.500s", fmtbuf);
 397                 closelog();
 398 #endif
 399         }
 400         errno = saved_errno;
 401 }