/****************************************************************************** * * Program: SNMP plugin for Nagios * License: GPL * * License Information: * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. *****************************************************************************/ #include "config.h" #include "common.h" #include "utils.h" #include "popen.h" #define PROGNAME "check_dig" #define REVISION "$Revision$" #define COPYRIGHT "2000-2002" #define AUTHOR "Karl DeBisschop" #define EMAIL "karl@debisschop.net" #define SUMMARY "Test the DNS service on the specified host using dig\n" int process_arguments (int, char **); int validate_arguments (void); void print_help (void); void print_usage (void); char *query_address = NULL; char *dns_server = NULL; int verbose = FALSE; int main (int argc, char **argv) { char input_buffer[MAX_INPUT_BUFFER]; char *command_line = NULL; char *output = ""; int result = STATE_UNKNOWN; /* Set signal handling and alarm */ if (signal (SIGALRM, popen_timeout_alarm_handler) == SIG_ERR) usage ("Cannot catch SIGALRM\n"); if (process_arguments (argc, argv) != OK) usage ("Could not parse arguments\n"); /* get the command to run */ asprintf (&command_line, "%s @%s %s", PATH_TO_DIG, dns_server, query_address); alarm (timeout_interval); time (&start_time); if (verbose) printf ("%s\n", command_line); /* run the command */ child_process = spopen (command_line); if (child_process == NULL) { printf ("Could not open pipe: %s\n", command_line); return STATE_UNKNOWN; } child_stderr = fdopen (child_stderr_array[fileno (child_process)], "r"); if (child_stderr == NULL) printf ("Could not open stderr for %s\n", command_line); output = strscpy (output, ""); while (fgets (input_buffer, MAX_INPUT_BUFFER - 1, child_process)) { /* the server is responding, we just got the host name... */ if (strstr (input_buffer, ";; ANSWER SECTION:")) { /* get the host address */ if (!fgets (input_buffer, MAX_INPUT_BUFFER - 1, child_process)) break; if (strpbrk (input_buffer, "\r\n")) input_buffer[strcspn (input_buffer, "\r\n")] = '\0'; if (strstr (input_buffer, query_address) == input_buffer) { output = strscpy (output, input_buffer); result = STATE_OK; } else { strscpy (output, "Server not found in ANSWER SECTION"); result = STATE_WARNING; } continue; } } if (result != STATE_OK) { strscpy (output, "No ANSWER SECTION found"); } while (fgets (input_buffer, MAX_INPUT_BUFFER - 1, child_stderr)) { /* If we get anything on STDERR, at least set warning */ result = max_state (result, STATE_WARNING); printf ("%s", input_buffer); if (!strcmp (output, "")) strscpy (output, 1 + index (input_buffer, ':')); } (void) fclose (child_stderr); /* close the pipe */ if (spclose (child_process)) { result = max_state (result, STATE_WARNING); if (!strcmp (output, "")) strscpy (output, "nslookup returned error status"); } (void) time (&end_time); if (result == STATE_OK) printf ("DNS ok - %d seconds response time (%s)\n", (int) (end_time - start_time), output); else if (result == STATE_WARNING) printf ("DNS WARNING - %s\n", !strcmp (output, "") ? " Probably a non-existent host/domain" : output); else if (result == STATE_CRITICAL) printf ("DNS CRITICAL - %s\n", !strcmp (output, "") ? " Probably a non-existent host/domain" : output); else printf ("DNS problem - %s\n", !strcmp (output, "") ? " Probably a non-existent host/domain" : output); return result; } /* process command-line arguments */ int process_arguments (int argc, char **argv) { int c; #ifdef HAVE_GETOPT_H int option_index = 0; static struct option long_options[] = { {"hostname", required_argument, 0, 'H'}, {"query_address", required_argument, 0, 'e'}, {"verbose", no_argument, 0, 'v'}, {"version", no_argument, 0, 'V'}, {"help", no_argument, 0, 'h'}, {0, 0, 0, 0} }; #endif if (argc < 2) return ERROR; while (1) { #ifdef HAVE_GETOPT_H c = getopt_long (argc, argv, "hVvt:l:H:", long_options, &option_index); #else c = getopt (argc, argv, "hVvt:l:H:"); #endif if (c == -1 || c == EOF) break; switch (c) { case '?': /* help */ usage3 ("Unknown argument", optopt); case 'H': /* hostname */ if (is_host (optarg)) { dns_server = optarg; } else { usage ("Invalid host name\n"); } break; case 'l': /* username */ query_address = optarg; break; case 'v': /* verbose */ verbose = TRUE; break; case 't': /* timeout */ if (is_intnonneg (optarg)) { timeout_interval = atoi (optarg); } else { usage ("Time interval must be a nonnegative integer\n"); } break; case 'V': /* version */ print_revision (PROGNAME, "$Revision$"); exit (STATE_OK); case 'h': /* help */ print_help (); exit (STATE_OK); } } c = optind; if (dns_server == NULL) { if (c < argc) { if (is_host (argv[c])) { dns_server = argv[c]; } else { usage ("Invalid host name"); } } else { dns_server = strscpy (NULL, "127.0.0.1"); } } return validate_arguments (); } int validate_arguments (void) { return OK; } void print_help (void) { print_revision (PROGNAME, "$Revision$"); printf ("Copyright (c) %s %s <%s>\n\n%s\n", COPYRIGHT, AUTHOR, EMAIL, SUMMARY); print_usage (); printf ("\nOptions:\n" " -H, --hostname=STRING or IPADDRESS\n" " Check server on the indicated host\n" " -l, --lookup=STRING\n" " machine name to lookup\n" " -t, --timeout=INTEGER\n" " Seconds before connection attempt times out (default: %d)\n" " -v, --verbose\n" " Print extra information (command-line use only)\n" " -h, --help\n" " Print detailed help screen\n" " -V, --version\n" " Print version information\n\n", DEFAULT_SOCKET_TIMEOUT); support (); } void print_usage (void) { printf ("Usage: %s -H host -l lookup [-t timeout] [-v]\n" " %s --help\n" " %s --version\n", PROGNAME, PROGNAME, PROGNAME); }