Работа с DNS

#!/usr/bin/perl

# Author: Sanjeev Jaiswal ( http://www.aliencoders.org/ )

# Description: It will take website name or IP address as an input

# It will display IP Address(es), name server(s), mail server(s) and SOA records if you pass website name

# It will display PTR record i.e. reverse lookup if you pass IP Address

# Currently we are not validating IP address though, but you modify to validate IP as well

use strict;

use warnings;

use Net::DNS;

use Net::IP;

die "Usage: perl $0 [site_name|IP Address]\n" unless(scalar $ARGV[0]);

my $site;

my $ip_address;

if($ARGV[0] =~/^(\d+\.){3}\d+$/){

  $ip_address = new Net::IP($ARGV[0],4);

} else {

  $site = $ARGV[0];

  $site =~ s#http[s]?://##;

  $site =~ s/www\.//;

  print "Not a valid site name format, Try again\n" and exit unless($site =~ /^((?!-)[A-Za-z0-9-]{1,63}(?<!-)\.)+[A-Za-z]{2,6}$/);

}

my $res = Net::DNS::Resolver->new;

if($site){

  show_ip();

  show_ns();

  show_mx();

  show_soa();

}

show_ip_lookup() if($ip_address);

# For IP Address

sub show_ip {

  my $query = $res->search($site);

  if ($query) {

    print "\nIP Address(es):\n";

    foreach my $rr ($query->answer) {

        next unless $rr->type eq "A";

        print $rr->address, "\n";

    }

  }

  else {

    warn "Query failed: ", $res->errorstring;

  }

}

#For Name servers

sub show_ns {

  my $reply = $res->query("$site", "NS");

  if ($reply) {

    print "\nName Server(s)\n";

    foreach my $rr (grep { $_->type eq "NS" } $reply->answer) {

      print $rr->nsdname, "\n";

    }

  }

  else {

    warn "query failed: ", $res->errorstring, "\n";

  }

}

# For Mail servers

sub show_mx {

  my @mx   = mx($res, $site);

  if (@mx) {

    print "\nMail Server(s)\n";

    foreach my $rr (@mx) {

      print $rr->preference, " ", $rr->exchange, "\n";

    }

  } else {

      warn "Can\'t find MX records for $site: ", $res->errorstring, "\n";

  }

}

#For SOA Records

sub show_soa {

  my $reply = $res->query("$site", "SOA");

  if ($reply) {

    print "\nSOA Record(s)\n";

   ($reply->answer)[0]->print;

  } else {

    print "query failed: ", $res->errorstring, "\n";

  }

}

#Show reverse lookup value of an IP Address

sub show_ip_lookup {

  my $answer = $res->query($ip_address->reverse_ip(),\'PTR\');

  my $namer  = $answer->{\'answer\'}[0];

  print "Reverse lookup: $namer->{\'ptrdname\'}\n" if(defined $namer->{\'ptrdname\'});

}

- See more at: http://www.aliencoders.org/forum/Thread-how-to-get-dns-information-using-perl-script#sthash.c4KmsWCr.dpuf