log.c

   1 /* $OpenBSD: log.c,v 1.40 2007/05/17 07:50:31 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
  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 LogLevel
 118 log_level_number(char *name)
 119 {
 120         int i;
 121
 122         if (name != NULL)
 123                 for (i = 0; log_levels[i].name; i++)
 124                         if (strcasecmp(log_levels[i].name, name) == 0)
 125                                 return log_levels[i].val;
 126         return SYSLOG_LEVEL_NOT_SET;
 127 }
 128
 129 /* Error messages that should be logged. */
 130
 131 void
 132 error(const char *fmt,...)
 133 {
 134         va_list args;
 135
 136         va_start(args, fmt);
 137         do_log(SYSLOG_LEVEL_ERROR, fmt, args);
 138         va_end(args);
 139 }
 140
 141 void
 142 sigdie(const char *fmt,...)
 143 {
 144 #ifdef DO_LOG_SAFE_IN_SIGHAND
 145         va_list args;
 146
 147         va_start(args, fmt);
 148         do_log(SYSLOG_LEVEL_FATAL, fmt, args);
 149         va_end(args);
 150 #endif
 151         _exit(1);
 152 }
 153
 154
 155 /* Log this message (information that usually should go to the log). */
 156
 157 void
 158 logit(const char *fmt,...)
 159 {
 160         va_list args;
 161
 162         va_start(args, fmt);
 163         do_log(SYSLOG_LEVEL_INFO, fmt, args);
 164         va_end(args);
 165 }
 166
 167 /* More detailed messages (information that does not need to go to the log). */
 168
 169 void
 170 verbose(const char *fmt,...)
 171 {
 172         va_list args;
 173
 174         va_start(args, fmt);
 175         do_log(SYSLOG_LEVEL_VERBOSE, fmt, args);
 176         va_end(args);
 177 }
 178
 179 /* Debugging messages that should not be logged during normal operation. */
 180
 181 void
 182 debug(const char *fmt,...)
 183 {
 184         va_list args;
 185
 186         va_start(args, fmt);
 187         do_log(SYSLOG_LEVEL_DEBUG1, fmt, args);
 188         va_end(args);
 189 }
 190
 191 void
 192 debug2(const char *fmt,...)
 193 {
 194         va_list args;
 195
 196         va_start(args, fmt);
 197         do_log(SYSLOG_LEVEL_DEBUG2, fmt, args);
 198         va_end(args);
 199 }
 200
 201 void
 202 debug3(const char *fmt,...)
 203 {
 204         va_list args;
 205
 206         va_start(args, fmt);
 207         do_log(SYSLOG_LEVEL_DEBUG3, fmt, args);
 208         va_end(args);
 209 }
 210
 211 /*
 212  * Initialize the log.
 213  */
 214
 215 void
 216 log_init(char *av0, LogLevel level, SyslogFacility facility, int on_stderr)
 217 {
 218 #if defined(HAVE_OPENLOG_R) && defined(SYSLOG_DATA_INIT)
 219         struct syslog_data sdata = SYSLOG_DATA_INIT;
 220 #endif
 221
 222         argv0 = av0;
 223
 224         switch (level) {
 225         case SYSLOG_LEVEL_QUIET:
 226         case SYSLOG_LEVEL_FATAL:
 227         case SYSLOG_LEVEL_ERROR:
 228         case SYSLOG_LEVEL_INFO:
 229         case SYSLOG_LEVEL_VERBOSE:
 230         case SYSLOG_LEVEL_DEBUG1:
 231         case SYSLOG_LEVEL_DEBUG2:
 232         case SYSLOG_LEVEL_DEBUG3:
 233                 log_level = level;
 234                 break;
 235         default:
 236                 fprintf(stderr, "Unrecognized internal syslog level code %d\n",
 237                     (int) level);
 238                 exit(1);
 239         }
 240
 241         log_on_stderr = on_stderr;
 242         if (on_stderr)
 243                 return;
 244
 245         switch (facility) {
 246         case SYSLOG_FACILITY_DAEMON:
 247                 log_facility = LOG_DAEMON;
 248                 break;
 249         case SYSLOG_FACILITY_USER:
 250                 log_facility = LOG_USER;
 251                 break;
 252         case SYSLOG_FACILITY_AUTH:
 253                 log_facility = LOG_AUTH;
 254                 break;
 255 #ifdef LOG_AUTHPRIV
 256         case SYSLOG_FACILITY_AUTHPRIV:
 257                 log_facility = LOG_AUTHPRIV;
 258                 break;
 259 #endif
 260         case SYSLOG_FACILITY_LOCAL0:
 261                 log_facility = LOG_LOCAL0;
 262                 break;
 263         case SYSLOG_FACILITY_LOCAL1:
 264                 log_facility = LOG_LOCAL1;
 265                 break;
 266         case SYSLOG_FACILITY_LOCAL2:
 267                 log_facility = LOG_LOCAL2;
 268                 break;
 269         case SYSLOG_FACILITY_LOCAL3:
 270                 log_facility = LOG_LOCAL3;
 271                 break;
 272         case SYSLOG_FACILITY_LOCAL4:
 273                 log_facility = LOG_LOCAL4;
 274                 break;
 275         case SYSLOG_FACILITY_LOCAL5:
 276                 log_facility = LOG_LOCAL5;
 277                 break;
 278         case SYSLOG_FACILITY_LOCAL6:
 279                 log_facility = LOG_LOCAL6;
 280                 break;
 281         case SYSLOG_FACILITY_LOCAL7:
 282                 log_facility = LOG_LOCAL7;
 283                 break;
 284         default:
 285                 fprintf(stderr,
 286                     "Unrecognized internal syslog facility code %d\n",
 287                     (int) facility);
 288                 exit(1);
 289         }
 290
 291         /*
 292          * If an external library (eg libwrap) attempts to use syslog
 293          * immediately after reexec, syslog may be pointing to the wrong
 294          * facility, so we force an open/close of syslog here.
 295          */
 296 #if defined(HAVE_OPENLOG_R) && defined(SYSLOG_DATA_INIT)
 297         openlog_r(argv0 ? argv0 : __progname, LOG_PID, log_facility, &sdata);
 298         closelog_r(&sdata);
 299 #else
 300         openlog(argv0 ? argv0 : __progname, LOG_PID, log_facility);
 301         closelog();
 302 #endif
 303 }
 304
 305 #define MSGBUFSIZ 1024
 306
 307 void
 308 do_log(LogLevel level, const char *fmt, va_list args)
 309 {
 310 #if defined(HAVE_OPENLOG_R) && defined(SYSLOG_DATA_INIT)
 311         struct syslog_data sdata = SYSLOG_DATA_INIT;
 312 #endif
 313         char msgbuf[MSGBUFSIZ];
 314         char fmtbuf[MSGBUFSIZ];
 315         char *txt = NULL;
 316         int pri = LOG_INFO;
 317         int saved_errno = errno;
 318
 319         if (level > log_level)
 320                 return;
 321
 322         switch (level) {
 323         case SYSLOG_LEVEL_FATAL:
 324                 if (!log_on_stderr)
 325                         txt = "fatal";
 326                 pri = LOG_CRIT;
 327                 break;
 328         case SYSLOG_LEVEL_ERROR:
 329                 if (!log_on_stderr)
 330                         txt = "error";
 331                 pri = LOG_ERR;
 332                 break;
 333         case SYSLOG_LEVEL_INFO:
 334                 pri = LOG_INFO;
 335                 break;
 336         case SYSLOG_LEVEL_VERBOSE:
 337                 pri = LOG_INFO;
 338                 break;
 339         case SYSLOG_LEVEL_DEBUG1:
 340                 txt = "debug1";
 341                 pri = LOG_DEBUG;
 342                 break;
 343         case SYSLOG_LEVEL_DEBUG2:
 344                 txt = "debug2";
 345                 pri = LOG_DEBUG;
 346                 break;
 347         case SYSLOG_LEVEL_DEBUG3:
 348                 txt = "debug3";
 349                 pri = LOG_DEBUG;
 350                 break;
 351         default:
 352                 txt = "internal error";
 353                 pri = LOG_ERR;
 354                 break;
 355         }
 356         if (txt != NULL) {
 357                 snprintf(fmtbuf, sizeof(fmtbuf), "%s: %s", txt, fmt);
 358                 vsnprintf(msgbuf, sizeof(msgbuf), fmtbuf, args);
 359         } else {
 360                 vsnprintf(msgbuf, sizeof(msgbuf), fmt, args);
 361         }
 362         strnvis(fmtbuf, msgbuf, sizeof(fmtbuf),
 363             log_on_stderr ? LOG_STDERR_VIS : LOG_SYSLOG_VIS);
 364         if (log_on_stderr) {
 365                 snprintf(msgbuf, sizeof msgbuf, "%s\r\n", fmtbuf);
 366                 write(STDERR_FILENO, msgbuf, strlen(msgbuf));
 367         } else {
 368 #if defined(HAVE_OPENLOG_R) && defined(SYSLOG_DATA_INIT)
 369                 openlog_r(argv0 ? argv0 : __progname, LOG_PID, log_facility, &sdata);
 370                 syslog_r(pri, &sdata, "%.500s", fmtbuf);
 371                 closelog_r(&sdata);
 372 #else
 373                 openlog(argv0 ? argv0 : __progname, LOG_PID, log_facility);
 374                 syslog(pri, "%.500s", fmtbuf);
 375                 closelog();
 376 #endif
 377         }
 378         errno = saved_errno;
 379 }