Ruby class to use the Blowfish encryption / decryption algorithm in a Rails environment. Based on https://gist.github.com/nono/2995118

blowfish.rb

#!/usr/bin/env ruby

require 'openssl'

class Blowfish
  def self.key
    Rails.application.secrets.secret_key_base
  end

  def self.encrypt(decrypted_string, salt=nil)
    decrypted_string += salt unless salt.nil?
    decrypted_string += ' ' until decrypted_string.bytesize % 8 == 0
    cipher = OpenSSL::Cipher.new('bf-ecb').encrypt
    cipher.padding = 0
    cipher.key = key

    binary_data = (cipher.update(decrypted_string) << cipher.final)
    binary_data.unpack('H*').first
  end

  def self.decrypt(encrypted_string, salt=nil)
    cipher = OpenSSL::Cipher.new('bf-ecb').decrypt
    cipher.padding = 0
    cipher.key = key

    binary_data = [encrypted_string].pack('H*')
    decrypted_string = cipher.update(binary_data) << cipher.final
    decrypted_string.force_encoding(Encoding::UTF_8)

    decrypted_string.strip!
    decrypted_string.gsub! /#{Regexp.quote(salt)}$/, '' unless salt.nil?

    decrypted_string
  end
end

# The encryption key is the Rails secret_key_base
bf = Blowfish.new
sentence = ARGV[0] || "foo bar foo bar foo bar foo bar foo bar foo bar baz"

# Use a salt parameter to enforce security against brute force attacks
salt = SecureRandom.hex
encrypted = bf.encrypt(sentence, salt)
puts encrypted.length
puts sentence.inspect
puts "Encrypt: #{encrypted}"
puts "Decoded: #{bf.decrypt encrypted, salt}"

Have you ever tried to run this code?