plugins/check_dig.c

   1 /*****************************************************************************
   2 *
   3 * Nagios check_dig plugin
   4 *
   5 * License: GPL
   6 * Copyright (c) 2002-2007 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 = "2002-2007";
  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 int verbose = FALSE;
  61 int server_port = DEFAULT_PORT;
  62 double warning_interval = UNDEFINED;
  63 double critical_interval = UNDEFINED;
  64 struct timeval tv;
  65
  66 int
  67 main (int argc, char **argv)
  68 {
  69   char *command_line;
  70   output chld_out, chld_err;
  71   char *msg = NULL;
  72   size_t i;
  73   char *t;
  74   long microsec;
  75   double elapsed_time;
  76   int result = STATE_UNKNOWN;
  77
  78   setlocale (LC_ALL, "");
  79   bindtextdomain (PACKAGE, LOCALEDIR);
  80   textdomain (PACKAGE);
  81
  82   /* Set signal handling and alarm */
  83   if (signal (SIGALRM, popen_timeout_alarm_handler) == SIG_ERR)
  84     usage_va(_("Cannot catch SIGALRM"));
  85
  86   if (process_arguments (argc, argv) == ERROR)
  87     usage_va(_("Could not parse arguments"));
  88
  89   /* get the command to run */
  90   asprintf (&command_line, "%s @%s -p %d %s -t %s",
  91             PATH_TO_DIG, dns_server, server_port, query_address, record_type);
  92
  93   alarm (timeout_interval);
  94   gettimeofday (&tv, NULL);
  95
  96   if (verbose) {
  97     printf ("%s\n", command_line);
  98     if(expected_address != NULL) {
  99       printf (_("Looking for: '%s'\n"), expected_address);
 100     } else {
 101       printf (_("Looking for: '%s'\n"), query_address);
 102     }
 103   }
 104
 105   /* run the command */
 106   if(np_runcmd(command_line, &chld_out, &chld_err, 0) != 0) {
 107     result = STATE_WARNING;
 108     msg = (char *)_("dig returned an error status");
 109   }
 110
 111   for(i = 0; i < chld_out.lines; i++) {
 112     /* the server is responding, we just got the host name... */
 113     if (strstr (chld_out.line[i], ";; ANSWER SECTION:")) {
 114
 115       /* loop through the whole 'ANSWER SECTION' */
 116       for(; i < chld_out.lines; i++) {
 117         /* get the host address */
 118         if (verbose)
 119           printf ("%s\n", chld_out.line[i]);
 120
 121         if (strstr (chld_out.line[i], (expected_address == NULL ? query_address : expected_address)) != NULL) {
 122           msg = chld_out.line[i];
 123           result = STATE_OK;
 124
 125           /* Translate output TAB -> SPACE */
 126           t = msg;
 127           while ((t = strchr(t, '\t')) != NULL) *t = ' ';
 128           break;
 129         }
 130       }
 131
 132       if (result == STATE_UNKNOWN) {
 133         msg = (char *)_("Server not found in ANSWER SECTION");
 134         result = STATE_WARNING;
 135       }
 136
 137       /* we found the answer section, so break out of the loop */
 138       break;
 139     }
 140   }
 141
 142   if (result == STATE_UNKNOWN)
 143     msg = (char *)_("No ANSWER SECTION found");
 144
 145   /* If we get anything on STDERR, at least set warning */
 146   if(chld_err.buflen > 0) {
 147     result = max_state(result, STATE_WARNING);
 148     if(!msg) for(i = 0; i < chld_err.lines; i++) {
 149       msg = strchr(chld_err.line[0], ':');
 150       if(msg) {
 151         msg++;
 152         break;
 153       }
 154     }
 155   }
 156
 157   microsec = deltime (tv);
 158   elapsed_time = (double)microsec / 1.0e6;
 159
 160   if (critical_interval > UNDEFINED && elapsed_time > critical_interval)
 161     result = STATE_CRITICAL;
 162
 163   else if (warning_interval > UNDEFINED && elapsed_time > warning_interval)
 164     result = STATE_WARNING;
 165
 166   printf ("DNS %s - %.3f seconds response time (%s)|%s\n",
 167           state_text (result), elapsed_time,
 168           msg ? msg : _("Probably a non-existent host/domain"),
 169           fperfdata("time", elapsed_time, "s",
 170                     (warning_interval>UNDEFINED?TRUE:FALSE),
 171                     warning_interval,
 172                     (critical_interval>UNDEFINED?TRUE:FALSE),
 173             critical_interval,
 174             TRUE, 0, FALSE, 0));
 175   return result;
 176 }
 177
 178
 179
 180 /* process command-line arguments */
 181 int
 182 process_arguments (int argc, char **argv)
 183 {
 184   int c;
 185
 186   int option = 0;
 187   static struct option longopts[] = {
 188     {"hostname", required_argument, 0, 'H'},
 189     {"query_address", required_argument, 0, 'l'},
 190     {"warning", required_argument, 0, 'w'},
 191     {"critical", required_argument, 0, 'c'},
 192     {"timeout", required_argument, 0, 't'},
 193     {"verbose", no_argument, 0, 'v'},
 194     {"version", no_argument, 0, 'V'},
 195     {"help", no_argument, 0, 'h'},
 196     {"record_type", required_argument, 0, 'T'},
 197     {"expected_address", required_argument, 0, 'a'},
 198     {"port", required_argument, 0, 'p'},
 199     {0, 0, 0, 0}
 200   };
 201
 202   if (argc < 2)
 203     return ERROR;
 204
 205   while (1) {
 206     c = getopt_long (argc, argv, "hVvt:l:H:w:c:T:p:a:", longopts, &option);
 207
 208     if (c == -1 || c == EOF)
 209       break;
 210
 211     switch (c) {
 212     case 'h':                 /* help */
 213       print_help ();
 214       exit (STATE_OK);
 215     case 'V':                 /* version */
 216       print_revision (progname, revision);
 217       exit (STATE_OK);
 218     case 'H':                 /* hostname */
 219       host_or_die(optarg);
 220       dns_server = optarg;
 221       break;
 222     case 'p':                 /* server port */
 223       if (is_intpos (optarg)) {
 224         server_port = atoi (optarg);
 225       }
 226       else {
 227         usage_va(_("Port must be a positive integer - %s"), optarg);
 228       }
 229       break;
 230     case 'l':                 /* address to lookup */
 231       query_address = optarg;
 232       break;
 233     case 'w':                 /* warning */
 234       if (is_nonnegative (optarg)) {
 235         warning_interval = strtod (optarg, NULL);
 236       }
 237       else {
 238         usage_va(_("Warning interval must be a positive integer - %s"), optarg);
 239       }
 240       break;
 241     case 'c':                 /* critical */
 242       if (is_nonnegative (optarg)) {
 243         critical_interval = strtod (optarg, NULL);
 244       }
 245       else {
 246         usage_va(_("Critical interval must be a positive integer - %s"), optarg);
 247       }
 248       break;
 249     case 't':                 /* timeout */
 250       if (is_intnonneg (optarg)) {
 251         timeout_interval = atoi (optarg);
 252       }
 253       else {
 254         usage_va(_("Timeout interval must be a positive integer - %s"), optarg);
 255       }
 256       break;
 257     case 'v':                 /* verbose */
 258       verbose = TRUE;
 259       break;
 260     case 'T':
 261       record_type = optarg;
 262       break;
 263     case 'a':
 264       expected_address = optarg;
 265       break;
 266     default:                  /* usage5 */
 267       usage5();
 268     }
 269   }
 270
 271   c = optind;
 272   if (dns_server == NULL) {
 273     if (c < argc) {
 274       host_or_die(argv[c]);
 275       dns_server = argv[c];
 276     }
 277     else {
 278       dns_server = strdup ("127.0.0.1");
 279     }
 280   }
 281
 282   return validate_arguments ();
 283 }
 284
 285
 286
 287 int
 288 validate_arguments (void)
 289 {
 290   return OK;
 291 }
 292
 293
 294
 295 void
 296 print_help (void)
 297 {
 298   char *myport;
 299
 300   asprintf (&myport, "%d", DEFAULT_PORT);
 301
 302   print_revision (progname, revision);
 303
 304   printf ("Copyright (c) 2000 Karl DeBisschop <kdebisschop@users.sourceforge.net>\n");
 305   printf (COPYRIGHT, copyright, email);
 306
 307   printf (_("This plugin test the DNS service on the specified host using dig"));
 308
 309   printf ("\n\n");
 310
 311   print_usage ();
 312
 313   printf (_(UT_HELP_VRSN));
 314
 315   printf (_(UT_HOST_PORT), 'p', myport);
 316
 317   printf (" %s\n","-l, --lookup=STRING");
 318   printf ("    %s\n",_("machine name to lookup"));
 319   printf (" %s\n","-T, --record_type=STRING");
 320   printf ("    %s\n",_("record type to lookup (default: A)"));
 321   printf (" %s\n","-a, --expected_address=STRING");
 322   printf ("    %s\n",_("an address expected to be in the answer section.if not set, uses whatever was in -l"));
 323   printf (_(UT_WARN_CRIT));
 324   printf (_(UT_TIMEOUT), DEFAULT_SOCKET_TIMEOUT);
 325   printf (_(UT_VERBOSE));
 326   printf (_(UT_SUPPORT));
 327 }
 328
 329
 330
 331 void
 332 print_usage (void)
 333 {
 334   printf (_("Usage:"));
 335   printf ("%s -H host -l lookup [-p <server port>] [-T <query type>]", progname);
 336   printf (" [-w <warning interval>] [-c <critical interval>] [-t <timeout>]");
 337   printf (" [-a <expected answer address>] [-v]\n");
 338 }