#!/usr/bin/ruby
#
# find all domains that bit-squat a given domain.
#
# Based on this article: http://domainincite.com/bit-squatting-%E2%80%93-the-latest-risk-to-domain-name-owners/
#
# improvements: use a regex rather than URI.parse

require 'uri'

def validate(url)
  uri = URI.parse(url)
  if uri.class != URI::HTTP
    false
  else
    true
  end
rescue URI::InvalidURIError
  false
end

domain = ARGV[0]

if domain.nil?
  puts "usage: bit_squat.rb <google>"
  exit -1
end

if /\./ =~ domain
  puts "don't put dots, just domain root"
end


bits = domain.unpack("B*")[0].chars.to_a

(0..bits.length).each do |idx|
  our_bits = bits.dup

  if our_bits[idx] == "0"
    our_bits[idx] = "1"
  else
    our_bits[idx] = "0"
  end

  squattable = [our_bits.join("")].pack("B*")

  if validate("http://#{squattable}.com")
    puts squattable
  end
end