plugins/check_dig.c

   1 /*****************************************************************************
   2 *
   3 * Monitoring check_dig plugin
   4 *
   5 * License: GPL
   6 * Copyright (c) 2002-2008 Monitoring 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 = "devel@monitoring-plugins.org";
  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 #define DEFAULT_TRIES 3
  52
  53 char *query_address = NULL;
  54 char *record_type = "A";
  55 char *expected_address = NULL;
  56 char *dns_server = NULL;
  57 char *dig_args = "";
  58 char *query_transport = "";
  59 int verbose = FALSE;
  60 int server_port = DEFAULT_PORT;
  61 int number_tries = DEFAULT_TRIES;
  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   int timeout_interval_dig;
  78
  79   setlocale (LC_ALL, "");
  80   bindtextdomain (PACKAGE, LOCALEDIR);
  81   textdomain (PACKAGE);
  82
  83   /* Set signal handling and alarm */
  84   if (signal (SIGALRM, runcmd_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   /* dig applies the timeout to each try, so we need to work around this */
  94   timeout_interval_dig = timeout_interval / number_tries + number_tries;
  95
  96   /* get the command to run */
  97   xasprintf (&command_line, "%s %s %s -p %d @%s %s %s +tries=%d +time=%d",
  98             PATH_TO_DIG, dig_args, query_transport, server_port, dns_server, query_address, record_type, number_tries, timeout_interval_dig);
  99
 100   alarm (timeout_interval);
 101   gettimeofday (&tv, NULL);
 102
 103   if (verbose) {
 104     printf ("%s\n", command_line);
 105     if(expected_address != NULL) {
 106       printf (_("Looking for: '%s'\n"), expected_address);
 107     } else {
 108       printf (_("Looking for: '%s'\n"), query_address);
 109     }
 110   }
 111
 112   /* run the command */
 113   if(np_runcmd(command_line, &chld_out, &chld_err, 0) != 0) {
 114     result = STATE_WARNING;
 115     msg = (char *)_("dig returned an error status");
 116   }
 117
 118   for(i = 0; i < chld_out.lines; i++) {
 119     /* the server is responding, we just got the host name... */
 120     if (strstr (chld_out.line[i], ";; ANSWER SECTION:")) {
 121
 122       /* loop through the whole 'ANSWER SECTION' */
 123       for(; i < chld_out.lines; i++) {
 124         /* get the host address */
 125         if (verbose)
 126           printf ("%s\n", chld_out.line[i]);
 127
 128         if (strstr (chld_out.line[i], (expected_address == NULL ? query_address : expected_address)) != NULL) {
 129           msg = chld_out.line[i];
 130           result = STATE_OK;
 131
 132           /* Translate output TAB -> SPACE */
 133           t = msg;
 134           while ((t = strchr(t, '\t')) != NULL) *t = ' ';
 135           break;
 136         }
 137       }
 138
 139       if (result == STATE_UNKNOWN) {
 140         msg = (char *)_("Server not found in ANSWER SECTION");
 141         result = STATE_WARNING;
 142       }
 143
 144       /* we found the answer section, so break out of the loop */
 145       break;
 146     }
 147   }
 148
 149   if (result == STATE_UNKNOWN) {
 150     msg = (char *)_("No ANSWER SECTION found");
 151     result = STATE_CRITICAL;
 152   }
 153
 154   /* If we get anything on STDERR, at least set warning */
 155   if(chld_err.buflen > 0) {
 156     result = max_state(result, STATE_WARNING);
 157     if(!msg) for(i = 0; i < chld_err.lines; i++) {
 158       msg = strchr(chld_err.line[0], ':');
 159       if(msg) {
 160         msg++;
 161         break;
 162       }
 163     }
 164   }
 165
 166   microsec = deltime (tv);
 167   elapsed_time = (double)microsec / 1.0e6;
 168
 169   if (critical_interval > UNDEFINED && elapsed_time > critical_interval)
 170     result = STATE_CRITICAL;
 171
 172   else if (warning_interval > UNDEFINED && elapsed_time > warning_interval)
 173     result = STATE_WARNING;
 174
 175   printf ("DNS %s - %.3f seconds response time (%s)|%s\n",
 176           state_text (result), elapsed_time,
 177           msg ? msg : _("Probably a non-existent host/domain"),
 178           fperfdata("time", elapsed_time, "s",
 179                     (warning_interval>UNDEFINED?TRUE:FALSE),
 180                     warning_interval,
 181                     (critical_interval>UNDEFINED?TRUE:FALSE),
 182             critical_interval,
 183             TRUE, 0, FALSE, 0));
 184   return result;
 185 }
 186
 187
 188
 189 /* process command-line arguments */
 190 int
 191 process_arguments (int argc, char **argv)
 192 {
 193   int c;
 194
 195   int option = 0;
 196   static struct option longopts[] = {
 197     {"hostname", required_argument, 0, 'H'},
 198     {"query_address", required_argument, 0, 'l'},
 199     {"warning", required_argument, 0, 'w'},
 200     {"critical", required_argument, 0, 'c'},
 201     {"timeout", required_argument, 0, 't'},
 202     {"dig-arguments", required_argument, 0, 'A'},
 203     {"verbose", no_argument, 0, 'v'},
 204     {"version", no_argument, 0, 'V'},
 205     {"help", no_argument, 0, 'h'},
 206     {"record_type", required_argument, 0, 'T'},
 207     {"expected_address", required_argument, 0, 'a'},
 208     {"port", required_argument, 0, 'p'},
 209     {"use-ipv4", no_argument, 0, '4'},
 210     {"use-ipv6", no_argument, 0, '6'},
 211     {0, 0, 0, 0}
 212   };
 213
 214   if (argc < 2)
 215     return ERROR;
 216
 217   while (1) {
 218     c = getopt_long (argc, argv, "hVvt:l:H:w:c:T:p:a:A:46", longopts, &option);
 219
 220     if (c == -1 || c == EOF)
 221       break;
 222
 223     switch (c) {
 224     case 'h':                 /* help */
 225       print_help ();
 226       exit (STATE_OK);
 227     case 'V':                 /* version */
 228       print_revision (progname, NP_VERSION);
 229       exit (STATE_OK);
 230     case 'H':                 /* hostname */
 231       host_or_die(optarg);
 232       dns_server = optarg;
 233       break;
 234     case 'p':                 /* server port */
 235       if (is_intpos (optarg)) {
 236         server_port = atoi (optarg);
 237       }
 238       else {
 239         usage_va(_("Port must be a positive integer - %s"), optarg);
 240       }
 241       break;
 242     case 'l':                 /* address to lookup */
 243       query_address = optarg;
 244       break;
 245     case 'w':                 /* warning */
 246       if (is_nonnegative (optarg)) {
 247         warning_interval = strtod (optarg, NULL);
 248       }
 249       else {
 250         usage_va(_("Warning interval must be a positive integer - %s"), optarg);
 251       }
 252       break;
 253     case 'c':                 /* critical */
 254       if (is_nonnegative (optarg)) {
 255         critical_interval = strtod (optarg, NULL);
 256       }
 257       else {
 258         usage_va(_("Critical interval must be a positive integer - %s"), optarg);
 259       }
 260       break;
 261     case 't':                 /* timeout */
 262       if (is_intnonneg (optarg)) {
 263         timeout_interval = atoi (optarg);
 264       }
 265       else {
 266         usage_va(_("Timeout interval must be a positive integer - %s"), optarg);
 267       }
 268       break;
 269     case 'A':                 /* dig arguments */
 270       dig_args = strdup(optarg);
 271       break;
 272     case 'v':                 /* verbose */
 273       verbose = TRUE;
 274       break;
 275     case 'T':
 276       record_type = optarg;
 277       break;
 278     case 'a':
 279       expected_address = optarg;
 280       break;
 281     case '4':
 282       query_transport = "-4";
 283       break;
 284     case '6':
 285       query_transport = "-6";
 286       break;
 287     default:                  /* usage5 */
 288       usage5();
 289     }
 290   }
 291
 292   c = optind;
 293   if (dns_server == NULL) {
 294     if (c < argc) {
 295       host_or_die(argv[c]);
 296       dns_server = argv[c];
 297     }
 298     else {
 299       if (strcmp(query_transport,"-6") == 0)
 300         dns_server = strdup("::1");
 301       else
 302         dns_server = strdup ("127.0.0.1");
 303     }
 304   }
 305
 306   return validate_arguments ();
 307 }
 308
 309
 310
 311 int
 312 validate_arguments (void)
 313 {
 314   if (query_address != NULL)
 315     return OK;
 316   else
 317     return ERROR;
 318 }
 319
 320
 321
 322 void
 323 print_help (void)
 324 {
 325   char *myport;
 326
 327   xasprintf (&myport, "%d", DEFAULT_PORT);
 328
 329   print_revision (progname, NP_VERSION);
 330
 331   printf ("Copyright (c) 2000 Karl DeBisschop <kdebisschop@users.sourceforge.net>\n");
 332   printf (COPYRIGHT, copyright, email);
 333
 334   printf (_("This plugin test the DNS service on the specified host using dig"));
 335
 336   printf ("\n\n");
 337
 338   print_usage ();
 339
 340   printf (UT_HELP_VRSN);
 341
 342   printf (UT_EXTRA_OPTS);
 343
 344   printf (UT_HOST_PORT, 'p', myport);
 345
 346   printf (" %s\n","-4, --use-ipv4");
 347   printf ("    %s\n",_("Force dig to only use IPv4 query transport"));
 348   printf (" %s\n","-6, --use-ipv6");
 349   printf ("    %s\n",_("Force dig to only use IPv6 query transport"));
 350   printf (" %s\n","-l, --query_address=STRING");
 351   printf ("    %s\n",_("Machine name to lookup"));
 352   printf (" %s\n","-T, --record_type=STRING");
 353   printf ("    %s\n",_("Record type to lookup (default: A)"));
 354   printf (" %s\n","-a, --expected_address=STRING");
 355   printf ("    %s\n",_("An address expected to be in the answer section. If not set, uses whatever"));
 356   printf ("    %s\n",_("was in -l"));
 357   printf (" %s\n","-A, --dig-arguments=STRING");
 358   printf ("    %s\n",_("Pass STRING as argument(s) to dig"));
 359   printf (UT_WARN_CRIT);
 360   printf (UT_CONN_TIMEOUT, DEFAULT_SOCKET_TIMEOUT);
 361   printf (UT_VERBOSE);
 362
 363   printf ("\n");
 364   printf ("%s\n", _("Examples:"));
 365   printf (" %s\n", "check_dig -H DNSSERVER -l www.example.com -A \"+tcp\"");
 366   printf (" %s\n", "This will send a tcp query to DNSSERVER for www.example.com");
 367
 368   printf (UT_SUPPORT);
 369 }
 370
 371
 372
 373 void
 374 print_usage (void)
 375 {
 376   printf ("%s\n", _("Usage:"));
 377   printf ("%s -l <query_address> [-H <host>] [-p <server port>]\n", progname);
 378   printf (" [-T <query type>] [-w <warning interval>] [-c <critical interval>]\n");
 379   printf (" [-t <timeout>] [-a <expected answer address>] [-v]\n");
 380 }