#!/usr/bin/perl

use Net::Netmask;

#$FS = '\t';
#$, = ' ';
$\ = "\n";


use Getopt::Long;
&GetOptions ("ip=s", "mask=s", "checkip=s", "help");

$ERRFLAG = 0;

if ( $opt_help == 1 ) {
  &usage;
  exit 0;
}

if ( !$opt_ip ) {
  print "option '--ip=aaa.bbb.ccc.ddd' is obligatory";
  $ERRFLAG = 1;
}

if ( !$opt_mask ) {
  print "option '--mask=aaa.bbb.ccc.ddd | --mask=0xaabbccdd' is obligatory";
  $ERRFLAG = 1;
}

if ( $ERRFLAG ) {
  &usage;
  exit 1;
}

$block = new Net::Netmask ($opt_ip, $opt_mask);
print "a.b.c.d/bits .... ", $block->desc();
print "netaddress ...... ", $block->base();
print "netmask ......... ", $block->mask();
print "broadcast ....... ", $block->broadcast();
print "hostmask ........ ", $block->hostmask();
#print "subnet-bits ..... ", $block->bits();
print "blocksize ....... ", $block->size();
print "hostaddresses ... ", $block->nth(1), " - ", $block->nth(-2);
print "next net ........ ", $block->next();
if ( $opt_checkip ) {
    print "\nchecked host .... ", $block->match($opt_checkip), "\nif 'checked host' = 0 then hostip doesn't match this network";
}

sub usage {
    print "\nusage: $0 [--help] --ip=ip-address --mask=netmask [--checkip=ip-address]\n";
    print "       ip-address    aaa.bbb.ccc.ddd (decimal)";
    print "       netmask       aaa.bbb.ccc.ddd | 0xaabbccdd (hexadecimal)\n";
    print "       checkip       aaa.bbb.ccc.ddd (decimal)";
    print "examples: $0 --ip=192.168.210.196 --mask=255.255.255.192";
    print "          $0 --ip=192.168.210.196 --mask=0xffffffc0";
    print "          $0 --ip=192.168.210.192 --mask=255.255.255.192 --checkip=192.168.210.196";
}