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 char *query_transport = "";
  58 int verbose = FALSE;
  59 int server_port = DEFAULT_PORT;
  60 double warning_interval = UNDEFINED;
  61 double critical_interval = UNDEFINED;
  62 struct timeval tv;
  63
  64 int
  65 main (int argc, char **argv)
  66 {
  67   char *command_line;
  68   output chld_out, chld_err;
  69   char *msg = NULL;
  70   size_t i;
  71   char *t;
  72   long microsec;
  73   double elapsed_time;
  74   int result = STATE_UNKNOWN;
  75
  76   setlocale (LC_ALL, "");
  77   bindtextdomain (PACKAGE, LOCALEDIR);
  78   textdomain (PACKAGE);
  79
  80   /* Set signal handling and alarm */
  81   if (signal (SIGALRM, runcmd_timeout_alarm_handler) == SIG_ERR)
  82     usage_va(_("Cannot catch SIGALRM"));
  83
  84   /* Parse extra opts if any */
  85   argv=np_extra_opts (&argc, argv, progname);
  86
  87   if (process_arguments (argc, argv) == ERROR)
  88     usage_va(_("Could not parse arguments"));
  89
  90   /* get the command to run */
  91   xasprintf (&command_line, "%s @%s -p %d %s -t %s %s %s",
  92             PATH_TO_DIG, dns_server, server_port, query_address, record_type, dig_args, query_transport);
  93
  94   alarm (timeout_interval);
  95   gettimeofday (&tv, NULL);
  96
  97   if (verbose) {
  98     printf ("%s\n", command_line);
  99     if(expected_address != NULL) {
 100       printf (_("Looking for: '%s'\n"), expected_address);
 101     } else {
 102       printf (_("Looking for: '%s'\n"), query_address);
 103     }
 104   }
 105
 106   /* run the command */
 107   if(np_runcmd(command_line, &chld_out, &chld_err, 0) != 0) {
 108     result = STATE_WARNING;
 109     msg = (char *)_("dig returned an error status");
 110   }
 111
 112   for(i = 0; i < chld_out.lines; i++) {
 113     /* the server is responding, we just got the host name... */
 114     if (strstr (chld_out.line[i], ";; ANSWER SECTION:")) {
 115
 116       /* loop through the whole 'ANSWER SECTION' */
 117       for(; i < chld_out.lines; i++) {
 118         /* get the host address */
 119         if (verbose)
 120           printf ("%s\n", chld_out.line[i]);
 121
 122         if (strstr (chld_out.line[i], (expected_address == NULL ? query_address : expected_address)) != NULL) {
 123           msg = chld_out.line[i];
 124           result = STATE_OK;
 125
 126           /* Translate output TAB -> SPACE */
 127           t = msg;
 128           while ((t = strchr(t, '\t')) != NULL) *t = ' ';
 129           break;
 130         }
 131       }
 132
 133       if (result == STATE_UNKNOWN) {
 134         msg = (char *)_("Server not found in ANSWER SECTION");
 135         result = STATE_WARNING;
 136       }
 137
 138       /* we found the answer section, so break out of the loop */
 139       break;
 140     }
 141   }
 142
 143   if (result == STATE_UNKNOWN) {
 144     msg = (char *)_("No ANSWER SECTION found");
 145     result = STATE_CRITICAL;
 146   }
 147
 148   /* If we get anything on STDERR, at least set warning */
 149   if(chld_err.buflen > 0) {
 150     result = max_state(result, STATE_WARNING);
 151     if(!msg) for(i = 0; i < chld_err.lines; i++) {
 152       msg = strchr(chld_err.line[0], ':');
 153       if(msg) {
 154         msg++;
 155         break;
 156       }
 157     }
 158   }
 159
 160   microsec = deltime (tv);
 161   elapsed_time = (double)microsec / 1.0e6;
 162
 163   if (critical_interval > UNDEFINED && elapsed_time > critical_interval)
 164     result = STATE_CRITICAL;
 165
 166   else if (warning_interval > UNDEFINED && elapsed_time > warning_interval)
 167     result = STATE_WARNING;
 168
 169   printf ("DNS %s - %.3f seconds response time (%s)|%s\n",
 170           state_text (result), elapsed_time,
 171           msg ? msg : _("Probably a non-existent host/domain"),
 172           fperfdata("time", elapsed_time, "s",
 173                     (warning_interval>UNDEFINED?TRUE:FALSE),
 174                     warning_interval,
 175                     (critical_interval>UNDEFINED?TRUE:FALSE),
 176             critical_interval,
 177             TRUE, 0, FALSE, 0));
 178   return result;
 179 }
 180
 181
 182
 183 /* process command-line arguments */
 184 int
 185 process_arguments (int argc, char **argv)
 186 {
 187   int c;
 188
 189   int option = 0;
 190   static struct option longopts[] = {
 191     {"hostname", required_argument, 0, 'H'},
 192     {"query_address", required_argument, 0, 'l'},
 193     {"warning", required_argument, 0, 'w'},
 194     {"critical", required_argument, 0, 'c'},
 195     {"timeout", required_argument, 0, 't'},
 196     {"dig-arguments", required_argument, 0, 'A'},
 197     {"verbose", no_argument, 0, 'v'},
 198     {"version", no_argument, 0, 'V'},
 199     {"help", no_argument, 0, 'h'},
 200     {"record_type", required_argument, 0, 'T'},
 201     {"expected_address", required_argument, 0, 'a'},
 202     {"port", required_argument, 0, 'p'},
 203     {"use-ipv4", no_argument, 0, '4'},
 204     {"use-ipv6", no_argument, 0, '6'},
 205     {0, 0, 0, 0}
 206   };
 207
 208   if (argc < 2)
 209     return ERROR;
 210
 211   while (1) {
 212     c = getopt_long (argc, argv, "hVvt:l:H:w:c:T:p:a:A:46", longopts, &option);
 213
 214     if (c == -1 || c == EOF)
 215       break;
 216
 217     switch (c) {
 218     case 'h':                 /* help */
 219       print_help ();
 220       exit (STATE_OK);
 221     case 'V':                 /* version */
 222       print_revision (progname, NP_VERSION);
 223       exit (STATE_OK);
 224     case 'H':                 /* hostname */
 225       host_or_die(optarg);
 226       dns_server = optarg;
 227       break;
 228     case 'p':                 /* server port */
 229       if (is_intpos (optarg)) {
 230         server_port = atoi (optarg);
 231       }
 232       else {
 233         usage_va(_("Port must be a positive integer - %s"), optarg);
 234       }
 235       break;
 236     case 'l':                 /* address to lookup */
 237       query_address = optarg;
 238       break;
 239     case 'w':                 /* warning */
 240       if (is_nonnegative (optarg)) {
 241         warning_interval = strtod (optarg, NULL);
 242       }
 243       else {
 244         usage_va(_("Warning interval must be a positive integer - %s"), optarg);
 245       }
 246       break;
 247     case 'c':                 /* critical */
 248       if (is_nonnegative (optarg)) {
 249         critical_interval = strtod (optarg, NULL);
 250       }
 251       else {
 252         usage_va(_("Critical interval must be a positive integer - %s"), optarg);
 253       }
 254       break;
 255     case 't':                 /* timeout */
 256       if (is_intnonneg (optarg)) {
 257         timeout_interval = atoi (optarg);
 258       }
 259       else {
 260         usage_va(_("Timeout interval must be a positive integer - %s"), optarg);
 261       }
 262       break;
 263     case 'A':                 /* dig arguments */
 264       dig_args = strdup(optarg);
 265       break;
 266     case 'v':                 /* verbose */
 267       verbose = TRUE;
 268       break;
 269     case 'T':
 270       record_type = optarg;
 271       break;
 272     case 'a':
 273       expected_address = optarg;
 274       break;
 275     case '4':
 276       query_transport = "-4";
 277       break;
 278     case '6':
 279       query_transport = "-6";
 280       break;
 281     default:                  /* usage5 */
 282       usage5();
 283     }
 284   }
 285
 286   c = optind;
 287   if (dns_server == NULL) {
 288     if (c < argc) {
 289       host_or_die(argv[c]);
 290       dns_server = argv[c];
 291     }
 292     else {
 293       dns_server = strdup ("127.0.0.1");
 294     }
 295   }
 296
 297   return validate_arguments ();
 298 }
 299
 300
 301
 302 int
 303 validate_arguments (void)
 304 {
 305   if (query_address != NULL)
 306     return OK;
 307   else
 308     return ERROR;
 309 }
 310
 311
 312
 313 void
 314 print_help (void)
 315 {
 316   char *myport;
 317
 318   xasprintf (&myport, "%d", DEFAULT_PORT);
 319
 320   print_revision (progname, NP_VERSION);
 321
 322   printf ("Copyright (c) 2000 Karl DeBisschop <kdebisschop@users.sourceforge.net>\n");
 323   printf (COPYRIGHT, copyright, email);
 324
 325   printf (_("This plugin test the DNS service on the specified host using dig"));
 326
 327   printf ("\n\n");
 328
 329   print_usage ();
 330
 331   printf (UT_HELP_VRSN);
 332
 333   printf (UT_EXTRA_OPTS);
 334
 335   printf (UT_HOST_PORT, 'p', myport);
 336
 337   printf (" %s\n","-4, --use-ipv4");
 338   printf ("    %s\n",_("Force dig to only use IPv4 query transport"));
 339   printf (" %s\n","-6, --use-ipv6");
 340   printf ("    %s\n",_("Force dig to only use IPv6 query transport"));
 341   printf (" %s\n","-l, --query_address=STRING");
 342   printf ("    %s\n",_("Machine name to lookup"));
 343   printf (" %s\n","-T, --record_type=STRING");
 344   printf ("    %s\n",_("Record type to lookup (default: A)"));
 345   printf (" %s\n","-a, --expected_address=STRING");
 346   printf ("    %s\n",_("An address expected to be in the answer section. If not set, uses whatever"));
 347   printf ("    %s\n",_("was in -l"));
 348   printf (" %s\n","-A, --dig-arguments=STRING");
 349   printf ("    %s\n",_("Pass STRING as argument(s) to dig"));
 350   printf (UT_WARN_CRIT);
 351   printf (UT_TIMEOUT, DEFAULT_SOCKET_TIMEOUT);
 352   printf (UT_VERBOSE);
 353
 354   printf ("\n");
 355   printf ("%s\n", _("Examples:"));
 356   printf (" %s\n", "check_dig -H DNSSERVER -l www.example.com -A \"+tcp\"");
 357   printf (" %s\n", "This will send a tcp query to DNSSERVER for www.example.com");
 358
 359   printf (UT_SUPPORT);
 360 }
 361
 362
 363
 364 void
 365 print_usage (void)
 366 {
 367   printf ("%s\n", _("Usage:"));
 368   printf ("%s -l <query_address> [-H <host>] [-p <server port>]\n", progname);
 369   printf (" [-T <query type>] [-w <warning interval>] [-c <critical interval>]\n");
 370   printf (" [-t <timeout>] [-a <expected answer address>] [-v]\n");
 371 }