Crypto module to encrypt/decrypt with AES128 and AES256

crypto.rb

module Crypto
  module AES128
    class << self
      def encrypt(data)
        aes = OpenSSL::Cipher.new('AES-128-CBC')
        aes.encrypt
        aes.key = Digest::MD5.digest(ENV['SECRET_KEY'])
        crypt = aes.update(data) + aes.final
        Base64.urlsafe_encode64(crypt)
      end

      def decrypt(data)
        aes = OpenSSL::Cipher.new('AES-128-CBC')
        aes.decrypt
        aes.key = Digest::MD5.digest(ENV['SECRET_KEY'])
        tempkey = Base64.urlsafe_decode64(data)
        aes.update(tempkey) + aes.final
      end
    end
  end

  module AES256
    class << self
      def encrypt(data)
        aes = OpenSSL::Cipher.new('AES-256-CBC')
        aes.encrypt
        aes.key = Digest::SHA256.digest(ENV['SECRET_KEY'])
        crypt = aes.update(data) + aes.final
        Base64.urlsafe_encode64(crypt)
      end

      def decrypt(data)
        aes = OpenSSL::Cipher.new('AES-256-CBC')
        aes.decrypt
        aes.key = Digest::SHA256.digest(ENV['SECRET_KEY'])
        tempkey = Base64.urlsafe_decode64(data)
        aes.update(tempkey) + aes.final
      end
    end
  end
end