How can I generate a range of IP addresses in Perl?

Question

I need to generate a list of IP-addresses (IPv4) in Perl. I have start and end addresses, for example 1.1.1.1 and 1.10.20.30. How can I print all the addresses inbetween?

Answer 1

It's all in how you code it. This is the fastest way I know.

my $start = 0x010101; # 1.1.1
my $end   = 0x0a141e; # 10.20.30

for my $ip ( $start..$end ) { 
    my @ip = ( $ip >> 16 & 0xff
             , $ip >>  8 & 0xff
             , $ip       & 0xff
             );
    print join( '.', 1, @ip ), "\n";
}

Answer 2

Use Net::IP's looping feature:

The + operator is overloaded in order to allow looping though a whole range of IP addresses:

Answer 3

TMTOWTDI:

sub inc_ip { $_[0] = pack "N", 1 + unpack "N", $_[0] }
my $start = 1.1.1.1;
my $end = 1.10.20.30;
for ( $ip = $start; $ip le $end; inc_ip($ip) ) {
    printf "%vd\n", $ip;
}

Answer 4

Use Net::IP. From the CPAN documentation:

my $ip = new Net::IP ('195.45.6.7 - 195.45.6.19') || die;
# Loop
do {
    print $ip->ip(), "\n";
} while (++$ip);

This approach is more flexible because Net::IP accepts CIDR notation e.g. 193.0.1/24 and also supports IPv6.

Edit: if you are working with netblocks specifically, you might investigate Net::Netmask.

Answer 5

I am able to print the ip addresses using the following 2 methods, but I am not able to save the individual elemens into an array.

For eg I am not able to :

sub inc_ip { $[0] = pack "N", 1 + unpack "N", $[0] } my $start = 1.1.1.1; my $end = 1.10.20.30; for ( $ip = $start; $ip le $end; inc_ip($ip) ) { printf "%vd\n", $ip; ---- This works push (@array, $ip) ; ---does not . How can I do this ?

}

Similarly

my $ip = new Net::IP ('195.45.6.7 - 195.45.6.19') || die; -- this works my $ip = new Net::IP ('$start - $end') || die; -- This does not work

Loop

do { print $ip->ip(), "\n"; push (@array,$ip->ip()) ; ---This does not work . } while (++$ip);