plugins-scripts/check_netdns.pl

   1 #!@PERL@ -w
   2
   3 # Perl version of check_dns plugin which calls DNS directly instead of
   4 # relying on nslookup (which has bugs)
   5 #
   6 # Copyright 2000, virCIO, LLP
   7 #
   8 # Revision 1.3  2002/05/07 05:35:49  sghosh
   9 # 2nd fix for ePN
  10 #
  11 # Revision 1.2  2002/05/02 16:43:29  sghosh
  12 # fix for embedded perl
  13 #
  14 # Revision 1.1.1.1  2002/02/28 06:43:00  egalstad
  15 # Initial import of existing plugin code
  16 #
  17 # Revision 1.1  2000/08/03 20:41:12  karldebisschop
  18 # rename to avoid conflict when installing
  19 #
  20 # Revision 1.1  2000/08/03 19:27:08  karldebisschop
  21 # use Net::DNS to check name server
  22 #
  23 # Revision 1.1  2000/07/20 19:09:13  cwg
  24 # All the pieces needed to use my version of check_dns.
  25 #
  26 #
  27
  28 use Getopt::Long;
  29 use Net::DNS;
  30 use FindBin;
  31 use lib "$FindBin::Bin";
  32 use utils;
  33
  34 my $PROGNAME = "check_netdns";
  35 sub print_help ();
  36 sub print_version();
  37 sub print_usage ();
  38
  39 $ENV{'PATH'}='@TRUSTED_PATH@';
  40 $ENV{'BASH_ENV'}='';
  41 $ENV{'ENV'}='';
  42
  43 Getopt::Long::Configure(`bundling`);
  44 GetOptions("V" => $opt_V,         "version" => $opt_V,
  45                                          "h" => $opt_h,         "help" => $opt_h,
  46                                          "t=i" => $opt_t,       "timeout=i" => $opt_t,
  47                                          "s=s" => $opt_s,       "server=s" => $opt_s,
  48                                          "H=s" => $opt_H,       "hostname=s" => $opt_H);
  49
  50 # -h means display verbose help screen
  51 if($opt_h){ print_help(); exit 3; }
  52
  53 # -V means display version number
  54 if ($opt_V) { print_version(); exit 3; }
  55
  56 # -H means host name
  57 $opt_H = shift unless ($opt_H);
  58 unless ($opt_H) { print_usage(); exit -1; }
  59 if ($opt_H &&
  60                 $opt_H =~ m/^([0-9]+.[0-9]+.[0-9]+.[0-9]+|[a-zA-Z][-a-zA-Z0]+(.[a-zA-Z][-a-zA-Z0]+)*)$/)
  61 {
  62         $host = $1;
  63 } else {
  64         print "$opt_H is not a valid host name";
  65         exit -1;
  66 }
  67
  68 # -s means server name
  69 $opt_s = shift unless ($opt_s);
  70 if ($opt_s) {
  71         if ($opt_s =~ m/^([0-9]+.[0-9]+.[0-9]+.[0-9]+|[a-zA-Z][-a-zA-Z0]+(.[a-zA-Z][-a-zA-Z0]+)*)$/)
  72         {
  73                 $server = $1;
  74         } else {
  75                 print "$opt_s is not a valid host name";
  76                 exit 3;
  77         }
  78 }
  79
  80 # -t means timeout
  81 my $timeout = 10 unless ($opt_t);
  82
  83 my $res = new Net::DNS::Resolver;
  84 #$res->debug(1);
  85 if ($server) {
  86         $res->nameservers($server);
  87 }
  88
  89 $res->tcp_timeout($timeout);
  90 $SIG{ALRM} = &catch_alarm;
  91 alarm($timeout);
  92
  93 $query = $res->query($host);
  94 if ($query) {
  95         my @answer = $query->answer;
  96         if (@answer) {
  97                 print join(`/`, map {
  98                         $_->type . ` ` . $_->rdatastr;
  99                 } @answer);
 100                 exit 0;
 101         } else {
 102                 print "empty answer";
 103                 exit 2;
 104         }
 105 }
 106 else {
 107         print "query failed: ", $res->errorstring, "";
 108         exit 2;
 109 }
 110
 111 sub catch_alarm {
 112         print "query timed out";
 113         exit 2;
 114 }
 115
 116 sub print_version () {
 117         my $arg0 =  $0;
 118         chomp $arg0;
 119         print "$arg0                        version 0.1";
 120 }
 121 sub print_help() {
 122         print_version();
 123         print "";
 124         print "Check if a nameserver can resolve a given hostname.";
 125         print "";
 126         print_usage();
 127         print "";
 128         print "-H, --hostname=HOST";
 129         print "   The name or address you want to query";
 130         print "-s, --server=HOST";
 131         print "   Optional DNS server you want to use for the lookup";
 132         print "-t, --timeout=INTEGER";
 133         print "   Seconds before connection times out (default: 10)";
 134         print "-h, --help";
 135         print "   Print detailed help";
 136         print "-V, --version";
 137         print "   Print version numbers and license information";
 138 }
 139
 140 sub print_usage () {
 141         my $arg0 = $0;
 142         chomp $arg0;
 143         print "$arg0 check_dns -H host [-s server] [-t timeout]";
 144         print "$arg0 [-h | --help]";
 145         print "$arg0 [-V | --version]";
 146 }
 147