#!/usr/bin/perl
# Buffer Overflow Pattern generator v 1.0
# Written by Wireghoul - http://www.justanotherhacker.com
use strict;
use warnings;

sub generate {
    my $len=shift;
    my $pattern='Aa0';
    my $out = '';
    while (length($out) < $len) {
        $out.=$pattern;
        $pattern++;
    }
    return substr($out,0,$len);
}

sub search {
    my $string = shift;
    # If we get a hex string, decode and reverse it
    if ($string =~ /0x/) {
        $string =~ s/([a-fA-F0-9][a-fA-F0-9])/chr(hex($1))/eg;
        $string =~ s/0x//;
        $string = reverse $string;
    }
    my $pat = 'Aa0';
    my $out = '';
    while ($out !~ m/$string/) {
        $out.=$pat;
        $pat++;
    }
    return index($out, $string);
}

if (!$ARGV[0]) { 
   print "Buffer overflow pattern generator by Wireghoul\n$0 <size> creates pattern of size characters\n$0 string finds offset of string in pattern\n"; 
   exit 0 ;
}
if ($ARGV[0] =~ m/^\d+$/) {
    print generate($ARGV[0])."\n";
} else {
    print search($ARGV[0])."\n";
}