plugins/check_dig.c

   1 /******************************************************************************
   2 *
   3 * check_dig.c
   4 *
   5 * Program: dig plugin for Nagios
   6 * License: GPL
   7 * Copyright (c) 2000
   8 *
   9 * $Id$
  10 *
  11 *****************************************************************************/
  12
  13 #include "config.h"
  14 #include "common.h"
  15 #include "utils.h"
  16 #include "popen.h"
  17
  18 #define PROGNAME "check_dig"
  19
  20 int process_arguments (int, char **);
  21 int call_getopt (int, char **);
  22 int validate_arguments (void);
  23 int check_disk (int usp, int free_disk);
  24 void print_help (void);
  25 void print_usage (void);
  26
  27 char *query_address = NULL;
  28 char *dns_server = NULL;
  29 int verbose = FALSE;
  30
  31 int
  32 main (int argc, char **argv)
  33 {
  34         char input_buffer[MAX_INPUT_BUFFER];
  35         char *command_line = NULL;
  36         char *output = NULL;
  37         int result = STATE_UNKNOWN;
  38
  39         /* Set signal handling and alarm */
  40         if (signal (SIGALRM, popen_timeout_alarm_handler) == SIG_ERR)
  41                 usage ("Cannot catch SIGALRM\n");
  42
  43         if (process_arguments (argc, argv) != OK)
  44                 usage ("Could not parse arguments\n");
  45
  46         /* get the command to run */
  47         command_line =
  48                 ssprintf (command_line, "%s @%s %s", PATH_TO_DIG, dns_server,
  49                                                         query_address);
  50
  51         alarm (timeout_interval);
  52         time (&start_time);
  53
  54         if (verbose)
  55                 printf ("%s\n", command_line);
  56         /* run the command */
  57         child_process = spopen (command_line);
  58         if (child_process == NULL) {
  59                 printf ("Could not open pipe: %s\n", command_line);
  60                 return STATE_UNKNOWN;
  61         }
  62
  63         child_stderr = fdopen (child_stderr_array[fileno (child_process)], "r");
  64         if (child_stderr == NULL)
  65                 printf ("Could not open stderr for %s\n", command_line);
  66
  67         output = strscpy (output, "");
  68
  69         while (fgets (input_buffer, MAX_INPUT_BUFFER - 1, child_process)) {
  70
  71                 /* the server is responding, we just got the host name... */
  72                 if (strstr (input_buffer, ";; ANSWER SECTION:")) {
  73
  74                         /* get the host address */
  75                         if (!fgets (input_buffer, MAX_INPUT_BUFFER - 1, child_process))
  76                                 break;
  77
  78                         if (strpbrk (input_buffer, "\r\n"))
  79                                 input_buffer[strcspn (input_buffer, "\r\n")] = '\0';
  80
  81                         if (strstr (input_buffer, query_address) == input_buffer) {
  82                                 output = strscpy (output, input_buffer);
  83                                 result = STATE_OK;
  84                         }
  85                         else {
  86                                 strcpy (output, "Server not found in ANSWER SECTION");
  87                                 result = STATE_WARNING;
  88                         }
  89
  90                         continue;
  91                 }
  92
  93         }
  94
  95         if (result != STATE_OK) {
  96                 strcpy (output, "No ANSWER SECTION found");
  97         }
  98
  99         while (fgets (input_buffer, MAX_INPUT_BUFFER - 1, child_stderr)) {
 100                 /* If we get anything on STDERR, at least set warning */
 101                 result = max_state (result, STATE_WARNING);
 102                 printf ("%s", input_buffer);
 103                 if (!strcmp (output, ""))
 104                         strcpy (output, 1 + index (input_buffer, ':'));
 105         }
 106
 107         (void) fclose (child_stderr);
 108
 109         /* close the pipe */
 110         if (spclose (child_process)) {
 111                 result = max_state (result, STATE_WARNING);
 112                 if (!strcmp (output, ""))
 113                         strcpy (output, "nslookup returned error status");
 114         }
 115
 116         (void) time (&end_time);
 117
 118         if (result == STATE_OK)
 119                 printf ("DNS ok - %d seconds response time (%s)\n",
 120                                                 (int) (end_time - start_time), output);
 121         else if (result == STATE_WARNING)
 122                 printf ("DNS WARNING - %s\n",
 123                                                 !strcmp (output,
 124                                                                                  "") ? " Probably a non-existent host/domain" : output);
 125         else if (result == STATE_CRITICAL)
 126                 printf ("DNS CRITICAL - %s\n",
 127                                                 !strcmp (output,
 128                                                                                  "") ? " Probably a non-existent host/domain" : output);
 129         else
 130                 printf ("DNS problem - %s\n",
 131                                                 !strcmp (output,
 132                                                                                  "") ? " Probably a non-existent host/domain" : output);
 133
 134         return result;
 135 }
 136
 137 /* process command-line arguments */
 138 int
 139 process_arguments (int argc, char **argv)
 140 {
 141         int c;
 142
 143         if (argc < 2)
 144                 return ERROR;
 145
 146
 147         c = 0;
 148         while ((c += (call_getopt (argc - c, &argv[c]))) < argc) {
 149
 150                 if (is_option (argv[c]))
 151                         continue;
 152
 153                 if (dns_server == NULL) {
 154                         if (is_host (argv[c])) {
 155                                 dns_server = argv[c];
 156                         }
 157                         else {
 158                                 usage ("Invalid host name");
 159                         }
 160                 }
 161         }
 162
 163         if (dns_server == NULL)
 164                 dns_server = strscpy (NULL, "127.0.0.1");
 165
 166         return validate_arguments ();
 167 }
 168
 169
 170
 171
 172
 173
 174 int
 175 call_getopt (int argc, char **argv)
 176 {
 177         int c, i = 0;
 178
 179 #ifdef HAVE_GETOPT_H
 180         int option_index = 0;
 181         static struct option long_options[] = {
 182                 {"hostname", required_argument, 0, 'H'},
 183                 {"query_address", required_argument, 0, 'e'},
 184                 {"verbose", no_argument, 0, 'v'},
 185                 {"version", no_argument, 0, 'V'},
 186                 {"help", no_argument, 0, 'h'},
 187                 {0, 0, 0, 0}
 188         };
 189 #endif
 190
 191         while (1) {
 192 #ifdef HAVE_GETOPT_H
 193                 c = getopt_long (argc, argv, "+hVvt:l:H:", long_options, &option_index);
 194 #else
 195                 c = getopt (argc, argv, "+?hVvt:l:H:");
 196 #endif
 197
 198                 i++;
 199
 200                 if (c == -1 || c == EOF || c == 1)
 201                         break;
 202
 203                 switch (c) {
 204                 case 't':
 205                 case 'l':
 206                 case 'H':
 207                         i++;
 208                 }
 209
 210                 switch (c) {
 211                 case 'H':                                                                       /* hostname */
 212                         if (is_host (optarg)) {
 213                                 dns_server = optarg;
 214                         }
 215                         else {
 216                                 usage ("Invalid host name\n");
 217                         }
 218                         break;
 219                 case 'l':                                                                       /* username */
 220                         query_address = optarg;
 221                         break;
 222                 case 'v':                                                                       /* verbose */
 223                         verbose = TRUE;
 224                         break;
 225                 case 't':                                                                       /* timeout */
 226                         if (is_intnonneg (optarg)) {
 227                                 timeout_interval = atoi (optarg);
 228                         }
 229                         else {
 230                                 usage ("Time interval must be a nonnegative integer\n");
 231                         }
 232                         break;
 233                 case 'V':                                                                       /* version */
 234                         print_revision (PROGNAME, "$Revision$");
 235                         exit (STATE_OK);
 236                 case 'h':                                                                       /* help */
 237                         print_help ();
 238                         exit (STATE_OK);
 239                 case '?':                                                                       /* help */
 240                         usage ("Invalid argument\n");
 241                 }
 242         }
 243         return i;
 244 }
 245
 246
 247
 248
 249
 250 int
 251 validate_arguments (void)
 252 {
 253         return OK;
 254 }
 255
 256
 257
 258
 259
 260 void
 261 print_help (void)
 262 {
 263         print_revision (PROGNAME, "$Revision$");
 264         printf
 265                 ("Copyright (c) 2000 Karl DeBisschop\n\n"
 266                  "This plugin use dig to test the DNS service on the specified host.\n\n");
 267         print_usage ();
 268         printf
 269                 ("\nOptions:\n"
 270                  " -H, --hostname=STRING or IPADDRESS\n"
 271                  "   Check server on the indicated host\n"
 272                  " -l, --lookup=STRING\n"
 273                  "   machine name to lookup\n"
 274                  " -t, --timeout=INTEGER\n"
 275                  "   Seconds before connection attempt times out (default: %d)\n"
 276                  " -v, --verbose\n"
 277                  "   Print extra information (command-line use only)\n"
 278                  " -h, --help\n"
 279                  "   Print detailed help screen\n"
 280                  " -V, --version\n"
 281                  "   Print version information\n\n", DEFAULT_SOCKET_TIMEOUT);
 282         support ();
 283 }
 284
 285
 286
 287
 288
 289 void
 290 print_usage (void)
 291 {
 292         printf
 293                 ("Usage: %s -H host -l lookup [-t timeout] [-v]\n"
 294                  "       %s --help\n"
 295                  "       %s --version\n", PROGNAME, PROGNAME, PROGNAME);
 296 }