Script that uses nmap to look for local devices that respond to broadcast ping and have open telnet ports

telscan

#!/usr/bin/env ruby
 
# Looks for local devices that respond to broadcast ping and have open telnet ports
 
`ifconfig`.scan(/broadcast ([\d.]+)/) do |b,|
  next unless b[/^(192|10)\./]
  puts "Scanning #{b.gsub(/255/, '*')}"
  `ping -c2 #{b}`.scan(/from ([\d.]+)/).uniq.sort_by {|a,|
    a.split('.').map {|p| p.to_i }
  }.each do |a,|
    if `nmap -Pn -sT -p 23 #{a}`.include? "open  telnet"
      arp = `arp #{a}`
      puts arp[/at/] ? arp : a
    end
  end
end