Ruby OpenSSL Cipher

decrypt.rb

require 'openssl'
require 'digest/sha1'
require 'yaml'

puts "Enter passphrase: "

passphrase = gets.chomp

cipher = OpenSSL::Cipher::Cipher.new("AES-256-CBC")

cipher.decrypt

cipher.key = Digest::SHA1.hexdigest(passphrase).unpack('a2'*32).map{|x| x.hex}.pack('c'*32)

config = YAML::load_file("config.yml")

cipher.iv = config[:iv]

output = ""
output << cipher.update(config[:encrypted])
output << cipher.final

puts "Decrypted text: #{output}"

exit

encrypt.rb

require 'openssl'
require 'digest/sha1'
require 'yaml'

puts "Enter passphrase: "

passphrase = gets.chomp

puts "Enter text to encrypt: "

encrypt = gets.chomp

puts "Encrypting '#{encrypt}' with AES-256-CBC using passphrase '#{passphrase}'"

cipher = OpenSSL::Cipher::Cipher.new("AES-256-CBC")
cipher.encrypt
# your pass is what is used to encrypt/decrypt
cipher.key = key = Digest::SHA1.hexdigest(passphrase).unpack('a2'*32).map{|x| x.hex}.pack('c'*32)
cipher.iv = iv = cipher.random_iv
encrypted = cipher.update(encrypt)
encrypted << cipher.final

puts "Saving encrypted result: '#{encrypted}' with iv: #{iv}"

yaml_obj = {
  :iv => iv,
  :encrypted => encrypted
}

File.open('config.yml', 'w') do |out|
  YAML::dump(yaml_obj, out)
end

exit

Nice. Now, this does mean that the log files will have the cleartext though :)