Perl DtDNS Client based on https://www.dtdns.com/info/downloads/dtdns-ssl.pm.txt

dtdns-ssl.pm

#!/usr/bin/perl
#
# SSL Client for DtDNS Version 1.0 06/01/01
# SSL Client for DtDNS Version 1.2 11/25/02
# SSL Client for DtDNS Version 1.3 10/17/14
# R.W. (Bob) Hughes
# Modified to check against nslookup by Kevin Killingsworth
# ver 1.2 added test for "not valid" hostname
# ver 1.3 changed external ip and dns lookup (Alexandre Aquiles)
#
# To add Net::SSLeay and LWP::Simple
# perl -MCPAN -eshell;
# cpan> install Net::SSLeay
# cpan> install Bundle::LWP
#========================================================================
require 5.004;
use Socket;
use Net::SSLeay qw(die_now die_if_ssl_error);
use Sys::Hostname;
use LWP::Simple;
use strict;
#========================================================================
if ($#ARGV < 0) {
   print "\nUsage:\n\n";
   print "  $0\t\tPrints this screen\n";
   print "  $0 up\tSends our current IP\n";
   print "  $0 down\tSends 0.0.0.0 to put this host off line\n";
   print "  $0 sync\tChecks NS IP against current IP and updates if needed\n";
   exit(1);
}
#========================================================================
# 
# You will need to change these as needed
#
my $DtDNS_hostname="xxx"; # Your DtDNS hostname
my $DtDNS_passwd="xxxxx";  # Your DtDNS password
my $DtDNS_domain="dtdns.net";   # Your DtDNS domain
my $Ext_port="eth0";            # Your Interface to the Big I

#========================================================================
my $remote  = 'www.dtdns.com';	
my $port    = 443;  		
#========================================================================
#
# Set the IP to either the IP of the Internet facing Interface or 0.0.0.0
# for off line notification, or check to see if they match and then
# set if they don't.
#

#
# Get the External IP
# (the real IP)
#
my ($My_ip);
chomp(my $My_ip = get("http://icanhazip.com/"));
die "Couldn't get external IP" unless defined $My_ip;
print "Current external IP: $My_ip\n";

#
# Get the NameServer IP
# (what the NameServer thinks the real IP is)
#
my $name = "$DtDNS_hostname.$DtDNS_domain";
my ($My_nsip);
$My_nsip = inet_ntoa(inet_aton($name)) or die "Couldn't resolve $name: $!\n";
print "Resolved '$name' to: $My_nsip\n";

#
# Now see what we need to be doing...
#
my $ToDo = shift(@ARGV);
$ToDo =~ tr/A-Z/a-z/;

if ($ToDo eq 'up' or $ToDo eq 'sync') {
	if ($My_ip eq $My_nsip) {
	# Do nothing, we've got everything right...
		print "NameServer IP is current.... Exiting\n";
		exit;
	} else {
	# Updatedate it...
		print "NameServer IP is out of date, updating...\n";
	}
} elsif ($ToDo eq 'down') {
	$My_ip = "0.0.0.0";  # Set the ip to 'offline'...
} else {
	print "The options are \"up\", \"down\" or \"sync\".... Exiting\n";
        exit;
}

#========================================================================
#
# Message to send
#
my $msg="GET /api/autodns.cfm?id=$DtDNS_hostname&pw=$DtDNS_passwd&ip=$My_ip HTTP/1.1\nHost: www.dtdns.com\nUser-Agent: Hugheshut-ssl\n\n";
#========================================================================
#
# Strict likes these
#
my ($iaddr, $paddr, $ctx, $ssl, $res, $got);
#========================================================================

Net::SSLeay::load_error_strings();
Net::SSLeay::SSLeay_add_ssl_algorithms();
Net::SSLeay::randomize();

if ($port =~ /\D/) { $port = getservbyname($port, 'tcp') }
die "No port" unless $port;

$iaddr   = inet_aton($remote)               	or die "No host: $remote";
$paddr   = sockaddr_in($port, $iaddr);

print "Contacting DtDNS for update...\n";

socket(S, &AF_INET, &SOCK_STREAM, 0)  	or die "Can Not create Socket: $!\n";
connect(S, $paddr)    			or die "Can not connect to DtDNS: $!\n";

select(S);
$| = 1;
select(STDOUT);

$ctx = Net::SSLeay::CTX_new()		or die_now("Failes to create SSL_CTX $!");
Net::SSLeay::CTX_set_options($ctx, &Net::SSLeay::OP_ALL)
    and die_if_ssl_error("ssl ctx set options");
$ssl = Net::SSLeay::new($ctx)		or die_now("Failed to create SSL $!");
Net::SSLeay::set_fd($ssl, fileno(S));
$res = Net::SSLeay::connect($ssl)	and die_if_ssl_error("ssl connect:");

#
# Informational
#
#print "Cipher '" . Net::SSLeay::get_cipher($ssl) . "'\n"; 

# Now Write the message
$res = Net::SSLeay::write($ssl, $msg)	or die_if_ssl_error("ssl write");
 
#print "Shutting down Socket\n";
shutdown S, 1;

while (1) {
$got = Net::SSLeay::read($ssl) 		or die_if_ssl_error("ssl read");
	if ($got=~/Host / or $got=~/not valid/) {
		print "$got\n";
                last;
	}
}

Net::SSLeay::free ($ssl);
Net::SSLeay::CTX_free ($ctx);

close (S)            			or die "close: $!";
exit;