plugins/check_dig.c

   1 /*****************************************************************************
   2 *
   3 * Nagios check_dig plugin
   4 *
   5 * License: GPL
   6 * Copyright (c) 1999-2006 nagios-plugins team
   7 *
   8 * Last Modified: $Date$
   9 *
  10 * Description:
  11 *
  12 * This file contains the check_dig plugin
  13 *
  14 * License Information:
  15 *
  16 * This program is free software; you can redistribute it and/or modify
  17 * it under the terms of the GNU General Public License as published by
  18 * the Free Software Foundation; either version 2 of the License, or
  19 * (at your option) any later version.
  20 *
  21 * This program is distributed in the hope that it will be useful,
  22 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  23 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  24 * GNU General Public License for more details.
  25 *
  26 * You should have received a copy of the GNU General Public License
  27 * along with this program; if not, write to the Free Software
  28 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  29 *
  30 * $Id$
  31 *
  32 *****************************************************************************/
  33
  34 /* Hackers note:
  35  *  There are typecasts to (char *) from _("foo bar") in this file.
  36  *  They prevent compiler warnings. Never (ever), permute strings obtained
  37  *  that are typecast from (const char *) (which happens when --disable-nls)
  38  *  because on some architectures those strings are in non-writable memory */
  39
  40 const char *progname = "check_dig";
  41 const char *revision = "$Revision$";
  42 const char *copyright = "2002-2006";
  43 const char *email = "nagiosplug-devel@lists.sourceforge.net";
  44
  45 #include "common.h"
  46 #include "netutils.h"
  47 #include "utils.h"
  48 #include "runcmd.h"
  49
  50 int process_arguments (int, char **);
  51 int validate_arguments (void);
  52 void print_help (void);
  53 void print_usage (void);
  54
  55 #define UNDEFINED 0
  56 #define DEFAULT_PORT 53
  57
  58 char *query_address = NULL;
  59 char *record_type = "A";
  60 char *expected_address = NULL;
  61 char *dns_server = NULL;
  62 int verbose = FALSE;
  63 int server_port = DEFAULT_PORT;
  64 double warning_interval = UNDEFINED;
  65 double critical_interval = UNDEFINED;
  66 struct timeval tv;
  67
  68 int
  69 main (int argc, char **argv)
  70 {
  71   char *command_line;
  72   output chld_out, chld_err;
  73   char *msg = NULL;
  74   size_t i;
  75   char *t;
  76   long microsec;
  77   double elapsed_time;
  78   int result = STATE_UNKNOWN;
  79
  80   setlocale (LC_ALL, "");
  81   bindtextdomain (PACKAGE, LOCALEDIR);
  82   textdomain (PACKAGE);
  83
  84   /* Set signal handling and alarm */
  85   if (signal (SIGALRM, popen_timeout_alarm_handler) == SIG_ERR)
  86     usage_va(_("Cannot catch SIGALRM"));
  87
  88   if (process_arguments (argc, argv) == ERROR)
  89     usage_va(_("Could not parse arguments"));
  90
  91   /* get the command to run */
  92   asprintf (&command_line, "%s @%s -p %d %s -t %s",
  93             PATH_TO_DIG, dns_server, server_port, query_address, record_type);
  94
  95   alarm (timeout_interval);
  96   gettimeofday (&tv, NULL);
  97
  98   if (verbose) {
  99     printf ("%s\n", command_line);
 100     if(expected_address != NULL) {
 101       printf (_("Looking for: '%s'\n"), expected_address);
 102     } else {
 103       printf (_("Looking for: '%s'\n"), query_address);
 104     }
 105   }
 106
 107   /* run the command */
 108   if(np_runcmd(command_line, &chld_out, &chld_err, 0) != 0) {
 109     result = STATE_WARNING;
 110     msg = (char *)_("dig returned an error status");
 111   }
 112
 113   for(i = 0; i < chld_out.lines; i++) {
 114     /* the server is responding, we just got the host name... */
 115     if (strstr (chld_out.line[i], ";; ANSWER SECTION:")) {
 116
 117       /* loop through the whole 'ANSWER SECTION' */
 118       for(; i < chld_out.lines; i++) {
 119         /* get the host address */
 120         if (verbose)
 121           printf ("%s\n", chld_out.line[i]);
 122
 123         if (strstr (chld_out.line[i], (expected_address == NULL ? query_address : expected_address)) != NULL) {
 124           msg = chld_out.line[i];
 125           result = STATE_OK;
 126
 127           /* Translate output TAB -> SPACE */
 128           t = msg;
 129           while ((t = strchr(t, '\t')) != NULL) *t = ' ';
 130           break;
 131         }
 132       }
 133
 134       if (result == STATE_UNKNOWN) {
 135         msg = (char *)_("Server not found in ANSWER SECTION");
 136         result = STATE_WARNING;
 137       }
 138
 139       /* we found the answer section, so break out of the loop */
 140       break;
 141     }
 142   }
 143
 144   if (result == STATE_UNKNOWN)
 145     msg = (char *)_("No ANSWER SECTION found");
 146
 147   /* If we get anything on STDERR, at least set warning */
 148   if(chld_err.buflen > 0) {
 149     result = max_state(result, STATE_WARNING);
 150     if(!msg) for(i = 0; i < chld_err.lines; i++) {
 151       msg = strchr(chld_err.line[0], ':');
 152       if(msg) {
 153         msg++;
 154         break;
 155       }
 156     }
 157   }
 158
 159   microsec = deltime (tv);
 160   elapsed_time = (double)microsec / 1.0e6;
 161
 162   if (critical_interval > UNDEFINED && elapsed_time > critical_interval)
 163     result = STATE_CRITICAL;
 164
 165   else if (warning_interval > UNDEFINED && elapsed_time > warning_interval)
 166     result = STATE_WARNING;
 167
 168   printf ("DNS %s - %.3f seconds response time (%s)|%s\n",
 169           state_text (result), elapsed_time,
 170           msg ? msg : _("Probably a non-existent host/domain"),
 171           fperfdata("time", elapsed_time, "s",
 172                     (warning_interval>UNDEFINED?TRUE:FALSE),
 173                     warning_interval,
 174                     (critical_interval>UNDEFINED?TRUE:FALSE),
 175             critical_interval,
 176             TRUE, 0, FALSE, 0));
 177   return result;
 178 }
 179
 180
 181
 182 /* process command-line arguments */
 183 int
 184 process_arguments (int argc, char **argv)
 185 {
 186   int c;
 187
 188   int option = 0;
 189   static struct option longopts[] = {
 190     {"hostname", required_argument, 0, 'H'},
 191     {"query_address", required_argument, 0, 'l'},
 192     {"warning", required_argument, 0, 'w'},
 193     {"critical", required_argument, 0, 'c'},
 194     {"timeout", required_argument, 0, 't'},
 195     {"verbose", no_argument, 0, 'v'},
 196     {"version", no_argument, 0, 'V'},
 197     {"help", no_argument, 0, 'h'},
 198     {"record_type", required_argument, 0, 'T'},
 199     {"expected_address", required_argument, 0, 'a'},
 200     {"port", required_argument, 0, 'p'},
 201     {0, 0, 0, 0}
 202   };
 203
 204   if (argc < 2)
 205     return ERROR;
 206
 207   while (1) {
 208     c = getopt_long (argc, argv, "hVvt:l:H:w:c:T:p:a:", longopts, &option);
 209
 210     if (c == -1 || c == EOF)
 211       break;
 212
 213     switch (c) {
 214     case 'h':                 /* help */
 215       print_help ();
 216       exit (STATE_OK);
 217     case 'V':                 /* version */
 218       print_revision (progname, revision);
 219       exit (STATE_OK);
 220     case 'H':                 /* hostname */
 221       host_or_die(optarg);
 222       dns_server = optarg;
 223       break;
 224     case 'p':                 /* server port */
 225       if (is_intpos (optarg)) {
 226         server_port = atoi (optarg);
 227       }
 228       else {
 229         usage_va(_("Port must be a positive integer - %s"), optarg);
 230       }
 231       break;
 232     case 'l':                 /* address to lookup */
 233       query_address = optarg;
 234       break;
 235     case 'w':                 /* warning */
 236       if (is_nonnegative (optarg)) {
 237         warning_interval = strtod (optarg, NULL);
 238       }
 239       else {
 240         usage_va(_("Warning interval must be a positive integer - %s"), optarg);
 241       }
 242       break;
 243     case 'c':                 /* critical */
 244       if (is_nonnegative (optarg)) {
 245         critical_interval = strtod (optarg, NULL);
 246       }
 247       else {
 248         usage_va(_("Critical interval must be a positive integer - %s"), optarg);
 249       }
 250       break;
 251     case 't':                 /* timeout */
 252       if (is_intnonneg (optarg)) {
 253         timeout_interval = atoi (optarg);
 254       }
 255       else {
 256         usage_va(_("Timeout interval must be a positive integer - %s"), optarg);
 257       }
 258       break;
 259     case 'v':                 /* verbose */
 260       verbose = TRUE;
 261       break;
 262     case 'T':
 263       record_type = optarg;
 264       break;
 265     case 'a':
 266       expected_address = optarg;
 267       break;
 268     default:                  /* usage5 */
 269       usage5();
 270     }
 271   }
 272
 273   c = optind;
 274   if (dns_server == NULL) {
 275     if (c < argc) {
 276       host_or_die(argv[c]);
 277       dns_server = argv[c];
 278     }
 279     else {
 280       dns_server = strdup ("127.0.0.1");
 281     }
 282   }
 283
 284   return validate_arguments ();
 285 }
 286
 287
 288
 289 int
 290 validate_arguments (void)
 291 {
 292   return OK;
 293 }
 294
 295
 296
 297 void
 298 print_help (void)
 299 {
 300   char *myport;
 301
 302   asprintf (&myport, "%d", DEFAULT_PORT);
 303
 304   print_revision (progname, revision);
 305
 306   printf ("Copyright (c) 2000 Karl DeBisschop <kdebisschop@users.sourceforge.net>\n");
 307   printf (COPYRIGHT, copyright, email);
 308
 309   printf (_("This plugin test the DNS service on the specified host using dig"));
 310
 311   printf ("\n\n");
 312
 313   print_usage ();
 314
 315   printf (_(UT_HELP_VRSN));
 316
 317   printf (_(UT_HOST_PORT), 'p', myport);
 318
 319   printf (" %s\n","-l, --lookup=STRING");
 320   printf ("    %s\n",_("machine name to lookup"));
 321   printf (" %s\n","-T, --record_type=STRING");
 322   printf ("    %s\n",_("record type to lookup (default: A)"));
 323   printf (" %s\n","-a, --expected_address=STRING");
 324   printf ("    %s\n",_("an address expected to be in the answer section.if not set, uses whatever was in -l"));
 325   printf (_(UT_WARN_CRIT));
 326   printf (_(UT_TIMEOUT), DEFAULT_SOCKET_TIMEOUT);
 327   printf (_(UT_VERBOSE));
 328   printf (_(UT_SUPPORT));
 329 }
 330
 331
 332
 333 void
 334 print_usage (void)
 335 {
 336   printf (_("Usage:"));
 337   printf ("%s -H host -l lookup [-p <server port>] [-T <query type>]", progname);
 338   printf (" [-w <warning interval>] [-c <critical interval>] [-t <timeout>]");
 339   printf (" [-a <expected answer address>] [-v]\n");
 340 }