plugins/check_dig.c

   1 /*****************************************************************************
   2 *
   3 * Nagios check_dig plugin
   4 *
   5 * License: GPL
   6 * Copyright (c) 2002-2008 Nagios Plugins Development Team
   7 *
   8 * Last Modified: $Date$
   9 *
  10 * Description:
  11 *
  12 * This file contains the check_dig plugin
  13 *
  14 *
  15 * This program is free software: you can redistribute it and/or modify
  16 * it under the terms of the GNU General Public License as published by
  17 * the Free Software Foundation, either version 3 of the License, or
  18 * (at your option) any later version.
  19 *
  20 * This program is distributed in the hope that it will be useful,
  21 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  22 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  23 * GNU General Public License for more details.
  24 *
  25 * You should have received a copy of the GNU General Public License
  26 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  27 *
  28 * $Id$
  29 *
  30 *****************************************************************************/
  31
  32 /* Hackers note:
  33  *  There are typecasts to (char *) from _("foo bar") in this file.
  34  *  They prevent compiler warnings. Never (ever), permute strings obtained
  35  *  that are typecast from (const char *) (which happens when --disable-nls)
  36  *  because on some architectures those strings are in non-writable memory */
  37
  38 const char *progname = "check_dig";
  39 const char *revision = "$Revision$";
  40 const char *copyright = "2002-2008";
  41 const char *email = "nagiosplug-devel@lists.sourceforge.net";
  42
  43 #include "common.h"
  44 #include "netutils.h"
  45 #include "utils.h"
  46 #include "runcmd.h"
  47
  48 int process_arguments (int, char **);
  49 int validate_arguments (void);
  50 void print_help (void);
  51 void print_usage (void);
  52
  53 #define UNDEFINED 0
  54 #define DEFAULT_PORT 53
  55
  56 char *query_address = NULL;
  57 char *record_type = "A";
  58 char *expected_address = NULL;
  59 char *dns_server = NULL;
  60 char *dig_args = "";
  61 int verbose = FALSE;
  62 int server_port = DEFAULT_PORT;
  63 double warning_interval = UNDEFINED;
  64 double critical_interval = UNDEFINED;
  65 struct timeval tv;
  66
  67 int
  68 main (int argc, char **argv)
  69 {
  70   char *command_line;
  71   output chld_out, chld_err;
  72   char *msg = NULL;
  73   size_t i;
  74   char *t;
  75   long microsec;
  76   double elapsed_time;
  77   int result = STATE_UNKNOWN;
  78
  79   setlocale (LC_ALL, "");
  80   bindtextdomain (PACKAGE, LOCALEDIR);
  81   textdomain (PACKAGE);
  82
  83   /* Set signal handling and alarm */
  84   if (signal (SIGALRM, popen_timeout_alarm_handler) == SIG_ERR)
  85     usage_va(_("Cannot catch SIGALRM"));
  86
  87   /* Parse extra opts if any */
  88   argv=np_extra_opts (&argc, argv, progname);
  89
  90   if (process_arguments (argc, argv) == ERROR)
  91     usage_va(_("Could not parse arguments"));
  92
  93   /* get the command to run */
  94   asprintf (&command_line, "%s @%s -p %d %s -t %s %s",
  95             PATH_TO_DIG, dns_server, server_port, query_address, record_type, dig_args);
  96
  97   alarm (timeout_interval);
  98   gettimeofday (&tv, NULL);
  99
 100   if (verbose) {
 101     printf ("%s\n", command_line);
 102     if(expected_address != NULL) {
 103       printf (_("Looking for: '%s'\n"), expected_address);
 104     } else {
 105       printf (_("Looking for: '%s'\n"), query_address);
 106     }
 107   }
 108
 109   /* run the command */
 110   if(np_runcmd(command_line, &chld_out, &chld_err, 0) != 0) {
 111     result = STATE_WARNING;
 112     msg = (char *)_("dig returned an error status");
 113   }
 114
 115   for(i = 0; i < chld_out.lines; i++) {
 116     /* the server is responding, we just got the host name... */
 117     if (strstr (chld_out.line[i], ";; ANSWER SECTION:")) {
 118
 119       /* loop through the whole 'ANSWER SECTION' */
 120       for(; i < chld_out.lines; i++) {
 121         /* get the host address */
 122         if (verbose)
 123           printf ("%s\n", chld_out.line[i]);
 124
 125         if (strstr (chld_out.line[i], (expected_address == NULL ? query_address : expected_address)) != NULL) {
 126           msg = chld_out.line[i];
 127           result = STATE_OK;
 128
 129           /* Translate output TAB -> SPACE */
 130           t = msg;
 131           while ((t = strchr(t, '\t')) != NULL) *t = ' ';
 132           break;
 133         }
 134       }
 135
 136       if (result == STATE_UNKNOWN) {
 137         msg = (char *)_("Server not found in ANSWER SECTION");
 138         result = STATE_WARNING;
 139       }
 140
 141       /* we found the answer section, so break out of the loop */
 142       break;
 143     }
 144   }
 145
 146   if (result == STATE_UNKNOWN)
 147     msg = (char *)_("No ANSWER SECTION found");
 148
 149   /* If we get anything on STDERR, at least set warning */
 150   if(chld_err.buflen > 0) {
 151     result = max_state(result, STATE_WARNING);
 152     if(!msg) for(i = 0; i < chld_err.lines; i++) {
 153       msg = strchr(chld_err.line[0], ':');
 154       if(msg) {
 155         msg++;
 156         break;
 157       }
 158     }
 159   }
 160
 161   microsec = deltime (tv);
 162   elapsed_time = (double)microsec / 1.0e6;
 163
 164   if (critical_interval > UNDEFINED && elapsed_time > critical_interval)
 165     result = STATE_CRITICAL;
 166
 167   else if (warning_interval > UNDEFINED && elapsed_time > warning_interval)
 168     result = STATE_WARNING;
 169
 170   printf ("DNS %s - %.3f seconds response time (%s)|%s\n",
 171           state_text (result), elapsed_time,
 172           msg ? msg : _("Probably a non-existent host/domain"),
 173           fperfdata("time", elapsed_time, "s",
 174                     (warning_interval>UNDEFINED?TRUE:FALSE),
 175                     warning_interval,
 176                     (critical_interval>UNDEFINED?TRUE:FALSE),
 177             critical_interval,
 178             TRUE, 0, FALSE, 0));
 179   return result;
 180 }
 181
 182
 183
 184 /* process command-line arguments */
 185 int
 186 process_arguments (int argc, char **argv)
 187 {
 188   int c;
 189
 190   int option = 0;
 191   static struct option longopts[] = {
 192     {"hostname", required_argument, 0, 'H'},
 193     {"query_address", required_argument, 0, 'l'},
 194     {"warning", required_argument, 0, 'w'},
 195     {"critical", required_argument, 0, 'c'},
 196     {"timeout", required_argument, 0, 't'},
 197     {"dig-arguments", required_argument, 0, 'A'},
 198     {"verbose", no_argument, 0, 'v'},
 199     {"version", no_argument, 0, 'V'},
 200     {"help", no_argument, 0, 'h'},
 201     {"record_type", required_argument, 0, 'T'},
 202     {"expected_address", required_argument, 0, 'a'},
 203     {"port", required_argument, 0, 'p'},
 204     {0, 0, 0, 0}
 205   };
 206
 207   if (argc < 2)
 208     return ERROR;
 209
 210   while (1) {
 211     c = getopt_long (argc, argv, "hVvt:l:H:w:c:T:p:a:A:", longopts, &option);
 212
 213     if (c == -1 || c == EOF)
 214       break;
 215
 216     switch (c) {
 217     case 'h':                 /* help */
 218       print_help ();
 219       exit (STATE_OK);
 220     case 'V':                 /* version */
 221       print_revision (progname, revision);
 222       exit (STATE_OK);
 223     case 'H':                 /* hostname */
 224       host_or_die(optarg);
 225       dns_server = optarg;
 226       break;
 227     case 'p':                 /* server port */
 228       if (is_intpos (optarg)) {
 229         server_port = atoi (optarg);
 230       }
 231       else {
 232         usage_va(_("Port must be a positive integer - %s"), optarg);
 233       }
 234       break;
 235     case 'l':                 /* address to lookup */
 236       query_address = optarg;
 237       break;
 238     case 'w':                 /* warning */
 239       if (is_nonnegative (optarg)) {
 240         warning_interval = strtod (optarg, NULL);
 241       }
 242       else {
 243         usage_va(_("Warning interval must be a positive integer - %s"), optarg);
 244       }
 245       break;
 246     case 'c':                 /* critical */
 247       if (is_nonnegative (optarg)) {
 248         critical_interval = strtod (optarg, NULL);
 249       }
 250       else {
 251         usage_va(_("Critical interval must be a positive integer - %s"), optarg);
 252       }
 253       break;
 254     case 't':                 /* timeout */
 255       if (is_intnonneg (optarg)) {
 256         timeout_interval = atoi (optarg);
 257       }
 258       else {
 259         usage_va(_("Timeout interval must be a positive integer - %s"), optarg);
 260       }
 261       break;
 262     case 'A':                 /* dig arguments */
 263       dig_args = strdup(optarg);
 264       break;
 265     case 'v':                 /* verbose */
 266       verbose = TRUE;
 267       break;
 268     case 'T':
 269       record_type = optarg;
 270       break;
 271     case 'a':
 272       expected_address = optarg;
 273       break;
 274     default:                  /* usage5 */
 275       usage5();
 276     }
 277   }
 278
 279   c = optind;
 280   if (dns_server == NULL) {
 281     if (c < argc) {
 282       host_or_die(argv[c]);
 283       dns_server = argv[c];
 284     }
 285     else {
 286       dns_server = strdup ("127.0.0.1");
 287     }
 288   }
 289
 290   return validate_arguments ();
 291 }
 292
 293
 294
 295 int
 296 validate_arguments (void)
 297 {
 298   return OK;
 299 }
 300
 301
 302
 303 void
 304 print_help (void)
 305 {
 306   char *myport;
 307
 308   asprintf (&myport, "%d", DEFAULT_PORT);
 309
 310   print_revision (progname, revision);
 311
 312   printf ("Copyright (c) 2000 Karl DeBisschop <kdebisschop@users.sourceforge.net>\n");
 313   printf (COPYRIGHT, copyright, email);
 314
 315   printf (_("This plugin test the DNS service on the specified host using dig"));
 316
 317   printf ("\n\n");
 318
 319   print_usage ();
 320
 321   printf (_(UT_HELP_VRSN));
 322
 323   printf (_(UT_EXTRA_OPTS));
 324
 325   printf (_(UT_HOST_PORT), 'p', myport);
 326
 327   printf (" %s\n","-l, --query_address=STRING");
 328   printf ("    %s\n",_("Machine name to lookup"));
 329   printf (" %s\n","-T, --record_type=STRING");
 330   printf ("    %s\n",_("Record type to lookup (default: A)"));
 331   printf (" %s\n","-a, --expected_address=STRING");
 332   printf ("    %s\n",_("An address expected to be in the answer section. If not set, uses whatever"));
 333   printf ("    %s\n",_("was in -l"));
 334   printf (" %s\n","-A, --dig-arguments=STRING");
 335   printf ("    %s\n",_("Pass STRING as argument(s) to dig"));
 336   printf (_(UT_WARN_CRIT));
 337   printf (_(UT_TIMEOUT), DEFAULT_SOCKET_TIMEOUT);
 338   printf (_(UT_VERBOSE));
 339
 340   printf ("\n");
 341   printf ("%s\n", _("Examples:"));
 342   printf (" %s\n", "check_dig -H DNSSERVER -l www.example.com -A \"+tcp\"");
 343   printf (" %s\n", "This will send a tcp query to DNSSERVER for www.example.com");
 344
 345 #ifdef NP_EXTRA_OPTS
 346   printf ("\n");
 347   printf ("%s\n", _("Notes:"));
 348   printf (_(UT_EXTRA_OPTS_NOTES));
 349 #endif
 350
 351   printf (_(UT_SUPPORT));
 352 }
 353
 354
 355
 356 void
 357 print_usage (void)
 358 {
 359   printf (_("Usage:"));
 360   printf ("%s -H <host> -l <query_address> [-p <server port>]\n", progname);
 361   printf (" [-T <query type>] [-w <warning interval>] [-c <critical interval>]\n");
 362   printf (" [-t <timeout>] [-a <expected answer address>] [-v]\n");
 363 }