sample encryption and decryption data with Advanced Encryption Standard (AES) for ruby

sample_encryption_decryption_with_aes_for_ruby.rb

# Encrypts and Decrypts block of data given an encryption key and an
# initialization vector (iv).  Keys, iv's, and the data returned
# are all binary strings.  Cipher algorithm should be array [256, CBC],
# or any of the cipher types supported by OpenSSL otherwise default will be used.
# Pass nil if the encryption type doesn't use iv's (like ECB) or ignore it if you using.

# USAGE:
# encrypt_to_hex_format(
#   'ThisPasswordIsReallyHardToGuess', 'initializervector', 'Hey! please encrypt me'
#   )

# decrypt_from_hex_format(
#   'ThisPasswordIsReallyHardToGuess', 'initializervector', 'Hey! pass encrypted string here'
#   )
require 'openssl'

module Aes
  def encrypt_to_hex_format(alg = 'aes-256-cbc', key, iv, data)
    bin2hex(send(:perform, :encrypt, alg, key, iv, data))
  end

  def decrypt_from_hex_format(alg = 'aes-256-cbc', key, iv, data)
    perform(:decrypt, alg, key, iv, send(:hex2bin, data))
  end

  def encrypt_to_base64_format; end # TODO:

  def decrypt_from_base64_format; end # TODO:

  def perform(method, alg, key, iv, data)
    cipher ||= OpenSSL::Cipher.new(alg)
    cipher.send(method)
    cipher.key = key
    cipher.iv = iv unless iv.nil?
    cipher.update(data) << cipher.final
  end

  private

  def bin2hex(str)
    str.unpack('C*').map { |b| '%02X' % b }.join('')
  end

  def hex2bin(str)
    [str].pack 'H*'
  end

  def bin2base64; end # TODO:

  def base64_bin; end # TODO:
end