Script to read information from remote X509 certificates

x509_cert_scan.rb

#!/usr/bin/env ruby

require 'openssl'
require 'socket'
require 'timeout'

DEFAULT_PORT=443
CONNECT_TIMEOUT=5

targets = ARGV.empty? ? ARGF : ARGV

targets.each do |target|
  begin
    host, port = target.chomp.split(':')
    port ||= DEFAULT_PORT

    print "#{host}:#{port}\t"

    Timeout::timeout(CONNECT_TIMEOUT) do
      tcp_sock = TCPSocket.new(host, port)
      ssl_sock = OpenSSL::SSL::SSLSocket.new(tcp_sock)
      ssl_sock.connect
      x509_cert = OpenSSL::X509::Certificate.new(ssl_sock.peer_cert)
      puts x509_cert.inspect
    end
  rescue SystemCallError, SocketError, OpenSSL::SSL::SSLError, Timeout::Error => e
    puts "#{e.class} - #{e}"
  end
end