log.c

   1 /* $OpenBSD: log.c,v 1.39 2006/08/18 09:13:25 deraadt 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 #if defined(HAVE_STRNVIS) && defined(HAVE_VIS_H)
  48 # include <vis.h>
  49 #endif
  50
  51 #include "xmalloc.h"
  52 #include "log.h"
  53
  54 static LogLevel log_level = SYSLOG_LEVEL_INFO;
  55 static int log_on_stderr = 1;
  56 static int log_facility = LOG_AUTH;
  57 static char *argv0;
  58
  59 extern char *__progname;
  60
  61 #define LOG_SYSLOG_VIS  (VIS_CSTYLE|VIS_NL|VIS_TAB|VIS_OCTAL)
  62 #define LOG_STDERR_VIS  (VIS_SAFE|VIS_OCTAL)
  63
  64 /* textual representation of log-facilities/levels */
  65
  66 static struct {
  67         const char *name;
  68         SyslogFacility val;
  69 } log_facilities[] = {
  70         { "DAEMON",     SYSLOG_FACILITY_DAEMON },
  71         { "USER",       SYSLOG_FACILITY_USER },
  72         { "AUTH",       SYSLOG_FACILITY_AUTH },
  73 #ifdef LOG_AUTHPRIV
  74         { "AUTHPRIV",   SYSLOG_FACILITY_AUTHPRIV },
  75 #endif
  76         { "LOCAL0",     SYSLOG_FACILITY_LOCAL0 },
  77         { "LOCAL1",     SYSLOG_FACILITY_LOCAL1 },
  78         { "LOCAL2",     SYSLOG_FACILITY_LOCAL2 },
  79         { "LOCAL3",     SYSLOG_FACILITY_LOCAL3 },
  80         { "LOCAL4",     SYSLOG_FACILITY_LOCAL4 },
  81         { "LOCAL5",     SYSLOG_FACILITY_LOCAL5 },
  82         { "LOCAL6",     SYSLOG_FACILITY_LOCAL6 },
  83         { "LOCAL7",     SYSLOG_FACILITY_LOCAL7 },
  84         { NULL,         SYSLOG_FACILITY_NOT_SET }
  85 };
  86
  87 static struct {
  88         const char *name;
  89         LogLevel val;
  90 } log_levels[] =
  91 {
  92         { "QUIET",      SYSLOG_LEVEL_QUIET },
  93         { "FATAL",      SYSLOG_LEVEL_FATAL },
  94         { "ERROR",      SYSLOG_LEVEL_ERROR },
  95         { "INFO",       SYSLOG_LEVEL_INFO },
  96         { "VERBOSE",    SYSLOG_LEVEL_VERBOSE },
  97         { "DEBUG",      SYSLOG_LEVEL_DEBUG1 },
  98         { "DEBUG1",     SYSLOG_LEVEL_DEBUG1 },
  99         { "DEBUG2",     SYSLOG_LEVEL_DEBUG2 },
 100         { "DEBUG3",     SYSLOG_LEVEL_DEBUG3 },
 101         { NULL,         SYSLOG_LEVEL_NOT_SET }
 102 };
 103
 104 SyslogFacility
 105 log_facility_number(char *name)
 106 {
 107         int i;
 108
 109         if (name != NULL)
 110                 for (i = 0; log_facilities[i].name; i++)
 111                         if (strcasecmp(log_facilities[i].name, name) == 0)
 112                                 return log_facilities[i].val;
 113         return SYSLOG_FACILITY_NOT_SET;
 114 }
 115
 116 LogLevel
 117 log_level_number(char *name)
 118 {
 119         int i;
 120
 121         if (name != NULL)
 122                 for (i = 0; log_levels[i].name; i++)
 123                         if (strcasecmp(log_levels[i].name, name) == 0)
 124                                 return log_levels[i].val;
 125         return SYSLOG_LEVEL_NOT_SET;
 126 }
 127
 128 /* Error messages that should be logged. */
 129
 130 void
 131 error(const char *fmt,...)
 132 {
 133         va_list args;
 134
 135         va_start(args, fmt);
 136         do_log(SYSLOG_LEVEL_ERROR, fmt, args);
 137         va_end(args);
 138 }
 139
 140 void
 141 sigdie(const char *fmt,...)
 142 {
 143 #ifdef DO_LOG_SAFE_IN_SIGHAND
 144         va_list args;
 145
 146         va_start(args, fmt);
 147         do_log(SYSLOG_LEVEL_FATAL, fmt, args);
 148         va_end(args);
 149 #endif
 150         _exit(1);
 151 }
 152
 153
 154 /* Log this message (information that usually should go to the log). */
 155
 156 void
 157 logit(const char *fmt,...)
 158 {
 159         va_list args;
 160
 161         va_start(args, fmt);
 162         do_log(SYSLOG_LEVEL_INFO, fmt, args);
 163         va_end(args);
 164 }
 165
 166 /* More detailed messages (information that does not need to go to the log). */
 167
 168 void
 169 verbose(const char *fmt,...)
 170 {
 171         va_list args;
 172
 173         va_start(args, fmt);
 174         do_log(SYSLOG_LEVEL_VERBOSE, fmt, args);
 175         va_end(args);
 176 }
 177
 178 /* Debugging messages that should not be logged during normal operation. */
 179
 180 void
 181 debug(const char *fmt,...)
 182 {
 183         va_list args;
 184
 185         va_start(args, fmt);
 186         do_log(SYSLOG_LEVEL_DEBUG1, fmt, args);
 187         va_end(args);
 188 }
 189
 190 void
 191 debug2(const char *fmt,...)
 192 {
 193         va_list args;
 194
 195         va_start(args, fmt);
 196         do_log(SYSLOG_LEVEL_DEBUG2, fmt, args);
 197         va_end(args);
 198 }
 199
 200 void
 201 debug3(const char *fmt,...)
 202 {
 203         va_list args;
 204
 205         va_start(args, fmt);
 206         do_log(SYSLOG_LEVEL_DEBUG3, fmt, args);
 207         va_end(args);
 208 }
 209
 210 /*
 211  * Initialize the log.
 212  */
 213
 214 void
 215 log_init(char *av0, LogLevel level, SyslogFacility facility, int on_stderr)
 216 {
 217 #if defined(HAVE_OPENLOG_R) && defined(SYSLOG_DATA_INIT)
 218         struct syslog_data sdata = SYSLOG_DATA_INIT;
 219 #endif
 220
 221         argv0 = av0;
 222
 223         switch (level) {
 224         case SYSLOG_LEVEL_QUIET:
 225         case SYSLOG_LEVEL_FATAL:
 226         case SYSLOG_LEVEL_ERROR:
 227         case SYSLOG_LEVEL_INFO:
 228         case SYSLOG_LEVEL_VERBOSE:
 229         case SYSLOG_LEVEL_DEBUG1:
 230         case SYSLOG_LEVEL_DEBUG2:
 231         case SYSLOG_LEVEL_DEBUG3:
 232                 log_level = level;
 233                 break;
 234         default:
 235                 fprintf(stderr, "Unrecognized internal syslog level code %d\n",
 236                     (int) level);
 237                 exit(1);
 238         }
 239
 240         log_on_stderr = on_stderr;
 241         if (on_stderr)
 242                 return;
 243
 244         switch (facility) {
 245         case SYSLOG_FACILITY_DAEMON:
 246                 log_facility = LOG_DAEMON;
 247                 break;
 248         case SYSLOG_FACILITY_USER:
 249                 log_facility = LOG_USER;
 250                 break;
 251         case SYSLOG_FACILITY_AUTH:
 252                 log_facility = LOG_AUTH;
 253                 break;
 254 #ifdef LOG_AUTHPRIV
 255         case SYSLOG_FACILITY_AUTHPRIV:
 256                 log_facility = LOG_AUTHPRIV;
 257                 break;
 258 #endif
 259         case SYSLOG_FACILITY_LOCAL0:
 260                 log_facility = LOG_LOCAL0;
 261                 break;
 262         case SYSLOG_FACILITY_LOCAL1:
 263                 log_facility = LOG_LOCAL1;
 264                 break;
 265         case SYSLOG_FACILITY_LOCAL2:
 266                 log_facility = LOG_LOCAL2;
 267                 break;
 268         case SYSLOG_FACILITY_LOCAL3:
 269                 log_facility = LOG_LOCAL3;
 270                 break;
 271         case SYSLOG_FACILITY_LOCAL4:
 272                 log_facility = LOG_LOCAL4;
 273                 break;
 274         case SYSLOG_FACILITY_LOCAL5:
 275                 log_facility = LOG_LOCAL5;
 276                 break;
 277         case SYSLOG_FACILITY_LOCAL6:
 278                 log_facility = LOG_LOCAL6;
 279                 break;
 280         case SYSLOG_FACILITY_LOCAL7:
 281                 log_facility = LOG_LOCAL7;
 282                 break;
 283         default:
 284                 fprintf(stderr,
 285                     "Unrecognized internal syslog facility code %d\n",
 286                     (int) facility);
 287                 exit(1);
 288         }
 289
 290         /*
 291          * If an external library (eg libwrap) attempts to use syslog
 292          * immediately after reexec, syslog may be pointing to the wrong
 293          * facility, so we force an open/close of syslog here.
 294          */
 295 #if defined(HAVE_OPENLOG_R) && defined(SYSLOG_DATA_INIT)
 296         openlog_r(argv0 ? argv0 : __progname, LOG_PID, log_facility, &sdata);
 297         closelog_r(&sdata);
 298 #else
 299         openlog(argv0 ? argv0 : __progname, LOG_PID, log_facility);
 300         closelog();
 301 #endif
 302 }
 303
 304 #define MSGBUFSIZ 1024
 305
 306 void
 307 do_log(LogLevel level, const char *fmt, va_list args)
 308 {
 309 #if defined(HAVE_OPENLOG_R) && defined(SYSLOG_DATA_INIT)
 310         struct syslog_data sdata = SYSLOG_DATA_INIT;
 311 #endif
 312         char msgbuf[MSGBUFSIZ];
 313         char fmtbuf[MSGBUFSIZ];
 314         char *txt = NULL;
 315         int pri = LOG_INFO;
 316
 317         if (level > log_level)
 318                 return;
 319
 320         switch (level) {
 321         case SYSLOG_LEVEL_FATAL:
 322                 if (!log_on_stderr)
 323                         txt = "fatal";
 324                 pri = LOG_CRIT;
 325                 break;
 326         case SYSLOG_LEVEL_ERROR:
 327                 if (!log_on_stderr)
 328                         txt = "error";
 329                 pri = LOG_ERR;
 330                 break;
 331         case SYSLOG_LEVEL_INFO:
 332                 pri = LOG_INFO;
 333                 break;
 334         case SYSLOG_LEVEL_VERBOSE:
 335                 pri = LOG_INFO;
 336                 break;
 337         case SYSLOG_LEVEL_DEBUG1:
 338                 txt = "debug1";
 339                 pri = LOG_DEBUG;
 340                 break;
 341         case SYSLOG_LEVEL_DEBUG2:
 342                 txt = "debug2";
 343                 pri = LOG_DEBUG;
 344                 break;
 345         case SYSLOG_LEVEL_DEBUG3:
 346                 txt = "debug3";
 347                 pri = LOG_DEBUG;
 348                 break;
 349         default:
 350                 txt = "internal error";
 351                 pri = LOG_ERR;
 352                 break;
 353         }
 354         if (txt != NULL) {
 355                 snprintf(fmtbuf, sizeof(fmtbuf), "%s: %s", txt, fmt);
 356                 vsnprintf(msgbuf, sizeof(msgbuf), fmtbuf, args);
 357         } else {
 358                 vsnprintf(msgbuf, sizeof(msgbuf), fmt, args);
 359         }
 360         strnvis(fmtbuf, msgbuf, sizeof(fmtbuf),
 361             log_on_stderr ? LOG_STDERR_VIS : LOG_SYSLOG_VIS);
 362         if (log_on_stderr) {
 363                 snprintf(msgbuf, sizeof msgbuf, "%s\r\n", fmtbuf);
 364                 write(STDERR_FILENO, msgbuf, strlen(msgbuf));
 365         } else {
 366 #if defined(HAVE_OPENLOG_R) && defined(SYSLOG_DATA_INIT)
 367                 openlog_r(argv0 ? argv0 : __progname, LOG_PID, log_facility, &sdata);
 368                 syslog_r(pri, &sdata, "%.500s", fmtbuf);
 369                 closelog_r(&sdata);
 370 #else
 371                 openlog(argv0 ? argv0 : __progname, LOG_PID, log_facility);
 372                 syslog(pri, "%.500s", fmtbuf);
 373                 closelog();
 374 #endif
 375         }
 376 }