Re: Re: Checking IP's with an IP/mask

I don't know much about network addresses, but isn't something like this sufficient?

use Socket;

sub IsInRange {
    my ($addr,$base) = @_;
    my $bits;
    ($base, $bits) = split /\//, $base;
    return ( (unpack("N", inet_aton($base)) >> (32 - $bits)) == 
        (unpack ("N", inet_aton($addr)) >> (32 - $bits)) );
}
[download]

Comment on Re: Re: Checking IP's with an IP/mask Download Code

Replies are listed 'Best First'.
Re^3: Checking IP's with an IP/mask by tadman (Prior) on Apr 24, 2001 at 18:49 UTC
This should work too, and is probably better because of simplicity. For those wondering, what this code effectively does is compare the network numbers of the $addr and the $base specification by shifting the host bits off the end (with the `>>` operator). What I was doing was building a range specification, which given the task, is really overkill. Well put.	[reply] [d/l]