#!/usr/bin/perl

use warnings;
use strict;
use CGI;
use CGI::Carp qw(fatalsToBrowser);

my $user = $ARGV[0];
my $password_old = $ARGV[1];
my $password_new = $ARGV[2];
my $host = $ARGV[3];

use Net::SSH::Expect;

my $ssh = Net::SSH::Expect->new (

   host => "$host",
   user => "$user",
   password => "$password_old",
   raw_pty => 1,

);

my $login_output = $ssh->login();

$ssh->exec("stty raw -echo");

$ssh->send("passwd");
$ssh->waitfor('password:\s*\z', 1) or die "prompt 'password' not found after 1 second";
$ssh->send("$password_old");
$ssh->waitfor(':\s*\z', 1) or die "prompt 'New password:' not found";
$ssh->send("$password_new");
$ssh->waitfor(':\s*\z', 1) or die "prompt 'Confirm new password:' not found";
$ssh->send("$password_new");
my ($before_match, $match) = $ssh->waitfor('>\s*\z', 1);  # waitfor() in a list context