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 * Description:
   9 *
  10 * This file contains the check_dig plugin
  11 *
  12 *
  13 * This program is free software: you can redistribute it and/or modify
  14 * it under the terms of the GNU General Public License as published by
  15 * the Free Software Foundation, either version 3 of the License, or
  16 * (at your option) any later version.
  17 *
  18 * This program is distributed in the hope that it will be useful,
  19 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  20 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  21 * GNU General Public License for more details.
  22 *
  23 * You should have received a copy of the GNU General Public License
  24 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  25 *
  26 *
  27 *****************************************************************************/
  28
  29 /* Hackers note:
  30  *  There are typecasts to (char *) from _("foo bar") in this file.
  31  *  They prevent compiler warnings. Never (ever), permute strings obtained
  32  *  that are typecast from (const char *) (which happens when --disable-nls)
  33  *  because on some architectures those strings are in non-writable memory */
  34
  35 const char *progname = "check_dig";
  36 const char *copyright = "2002-2008";
  37 const char *email = "nagiosplug-devel@lists.sourceforge.net";
  38
  39 #include "common.h"
  40 #include "netutils.h"
  41 #include "utils.h"
  42 #include "runcmd.h"
  43
  44 int process_arguments (int, char **);
  45 int validate_arguments (void);
  46 void print_help (void);
  47 void print_usage (void);
  48
  49 #define UNDEFINED 0
  50 #define DEFAULT_PORT 53
  51
  52 char *query_address = NULL;
  53 char *record_type = "A";
  54 char *expected_address = NULL;
  55 char *dns_server = NULL;
  56 char *dig_args = "";
  57 int verbose = FALSE;
  58 int server_port = DEFAULT_PORT;
  59 double warning_interval = UNDEFINED;
  60 double critical_interval = UNDEFINED;
  61 struct timeval tv;
  62
  63 int
  64 main (int argc, char **argv)
  65 {
  66   char *command_line;
  67   output chld_out, chld_err;
  68   char *msg = NULL;
  69   size_t i;
  70   char *t;
  71   long microsec;
  72   double elapsed_time;
  73   int result = STATE_UNKNOWN;
  74
  75   setlocale (LC_ALL, "");
  76   bindtextdomain (PACKAGE, LOCALEDIR);
  77   textdomain (PACKAGE);
  78
  79   /* Set signal handling and alarm */
  80   if (signal (SIGALRM, popen_timeout_alarm_handler) == SIG_ERR)
  81     usage_va(_("Cannot catch SIGALRM"));
  82
  83   /* Parse extra opts if any */
  84   argv=np_extra_opts (&argc, argv, progname);
  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 %s",
  91             PATH_TO_DIG, dns_server, server_port, query_address, record_type, dig_args);
  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     result = STATE_CRITICAL;
 145   }
 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     {"dig-arguments", required_argument, 0, 'A'},
 196     {"verbose", no_argument, 0, 'v'},
 197     {"version", no_argument, 0, 'V'},
 198     {"help", no_argument, 0, 'h'},
 199     {"record_type", required_argument, 0, 'T'},
 200     {"expected_address", required_argument, 0, 'a'},
 201     {"port", required_argument, 0, 'p'},
 202     {0, 0, 0, 0}
 203   };
 204
 205   if (argc < 2)
 206     return ERROR;
 207
 208   while (1) {
 209     c = getopt_long (argc, argv, "hVvt:l:H:w:c:T:p:a:A:", longopts, &option);
 210
 211     if (c == -1 || c == EOF)
 212       break;
 213
 214     switch (c) {
 215     case 'h':                 /* help */
 216       print_help ();
 217       exit (STATE_OK);
 218     case 'V':                 /* version */
 219       print_revision (progname, NP_VERSION);
 220       exit (STATE_OK);
 221     case 'H':                 /* hostname */
 222       host_or_die(optarg);
 223       dns_server = optarg;
 224       break;
 225     case 'p':                 /* server port */
 226       if (is_intpos (optarg)) {
 227         server_port = atoi (optarg);
 228       }
 229       else {
 230         usage_va(_("Port must be a positive integer - %s"), optarg);
 231       }
 232       break;
 233     case 'l':                 /* address to lookup */
 234       query_address = optarg;
 235       break;
 236     case 'w':                 /* warning */
 237       if (is_nonnegative (optarg)) {
 238         warning_interval = strtod (optarg, NULL);
 239       }
 240       else {
 241         usage_va(_("Warning interval must be a positive integer - %s"), optarg);
 242       }
 243       break;
 244     case 'c':                 /* critical */
 245       if (is_nonnegative (optarg)) {
 246         critical_interval = strtod (optarg, NULL);
 247       }
 248       else {
 249         usage_va(_("Critical interval must be a positive integer - %s"), optarg);
 250       }
 251       break;
 252     case 't':                 /* timeout */
 253       if (is_intnonneg (optarg)) {
 254         timeout_interval = atoi (optarg);
 255       }
 256       else {
 257         usage_va(_("Timeout interval must be a positive integer - %s"), optarg);
 258       }
 259       break;
 260     case 'A':                 /* dig arguments */
 261       dig_args = strdup(optarg);
 262       break;
 263     case 'v':                 /* verbose */
 264       verbose = TRUE;
 265       break;
 266     case 'T':
 267       record_type = optarg;
 268       break;
 269     case 'a':
 270       expected_address = optarg;
 271       break;
 272     default:                  /* usage5 */
 273       usage5();
 274     }
 275   }
 276
 277   c = optind;
 278   if (dns_server == NULL) {
 279     if (c < argc) {
 280       host_or_die(argv[c]);
 281       dns_server = argv[c];
 282     }
 283     else {
 284       dns_server = strdup ("127.0.0.1");
 285     }
 286   }
 287
 288   return validate_arguments ();
 289 }
 290
 291
 292
 293 int
 294 validate_arguments (void)
 295 {
 296   if (query_address != NULL)
 297     return OK;
 298   else
 299     return ERROR;
 300 }
 301
 302
 303
 304 void
 305 print_help (void)
 306 {
 307   char *myport;
 308
 309   asprintf (&myport, "%d", DEFAULT_PORT);
 310
 311   print_revision (progname, NP_VERSION);
 312
 313   printf ("Copyright (c) 2000 Karl DeBisschop <kdebisschop@users.sourceforge.net>\n");
 314   printf (COPYRIGHT, copyright, email);
 315
 316   printf (_("This plugin test the DNS service on the specified host using dig"));
 317
 318   printf ("\n\n");
 319
 320   print_usage ();
 321
 322   printf (_(UT_HELP_VRSN));
 323
 324   printf (_(UT_EXTRA_OPTS));
 325
 326   printf (_(UT_HOST_PORT), 'p', myport);
 327
 328   printf (" %s\n","-l, --query_address=STRING");
 329   printf ("    %s\n",_("Machine name to lookup"));
 330   printf (" %s\n","-T, --record_type=STRING");
 331   printf ("    %s\n",_("Record type to lookup (default: A)"));
 332   printf (" %s\n","-a, --expected_address=STRING");
 333   printf ("    %s\n",_("An address expected to be in the answer section. If not set, uses whatever"));
 334   printf ("    %s\n",_("was in -l"));
 335   printf (" %s\n","-A, --dig-arguments=STRING");
 336   printf ("    %s\n",_("Pass STRING as argument(s) to dig"));
 337   printf (_(UT_WARN_CRIT));
 338   printf (_(UT_TIMEOUT), DEFAULT_SOCKET_TIMEOUT);
 339   printf (_(UT_VERBOSE));
 340
 341   printf ("\n");
 342   printf ("%s\n", _("Examples:"));
 343   printf (" %s\n", "check_dig -H DNSSERVER -l www.example.com -A \"+tcp\"");
 344   printf (" %s\n", "This will send a tcp query to DNSSERVER for www.example.com");
 345
 346 #ifdef NP_EXTRA_OPTS
 347   printf ("\n");
 348   printf ("%s\n", _("Notes:"));
 349   printf (_(UT_EXTRA_OPTS_NOTES));
 350 #endif
 351
 352   printf (_(UT_SUPPORT));
 353 }
 354
 355
 356
 357 void
 358 print_usage (void)
 359 {
 360   printf (_("Usage:"));
 361   printf ("%s -l <query_address> [-H <host>] [-p <server port>]\n", progname);
 362   printf (" [-T <query type>] [-w <warning interval>] [-c <critical interval>]\n");
 363   printf (" [-t <timeout>] [-a <expected answer address>] [-v]\n");
 364 }