I'm trying to learn more Perl. I've wanted to recreate the functionality of dsniff in Perl. I'm still relatively new to Perl, and not all that familiar with regex, but I think that's what I'll need to use. My current code is: 
#!/usr/bin/perl -w

use strict;
use Net::PcapUtils;
use NetPacket::Ethernet qw(:strip);
use NetPacket::IP qw(:strip);
use NetPacket::TCP;

sub process_pkt {
    my($arg, $hdr, $pkt) = @_;

    my $tcp_obj = NetPacket::TCP->decode(ip_strip(eth_strip($pkt)));

    if (($tcp_obj->{src_port} == 80) or ($tcp_obj->{dest_port} == 80))
+ {
        print ($tcp_obj->{data});
    }
}

Net::PcapUtils::loop(\&process_pkt, FILTER => 'tcp');

[download]
This prints ALL the data going via HTTP. How would/should I go about parsing out JUST the GET string with the full URL information? Your help is greatly appreciated.

In reply to recreate dsniff in perl by nashr

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