encrypted_attributes ¶ ↑

encrypted_attributes adds support for automatically encrypting ActiveRecord attributes.

Resources¶ ↑

API

• rdoc.info/github/pluginaweek/encrypted_attributes/master/frames

Bugs

• github.com/pluginaweek/encrypted_attributes/issues

Development

• github.com/pluginaweek/encrypted_attributes

Testing

• travis-ci.org/pluginaweek/encrypted_attributes

Source

• git://github.com/pluginaweek/encrypted_attributes.git

Mailing List

• groups.google.com/group/pluginaweek-talk

Description¶ ↑

Encrypting attributes can be repetitive especially when doing so throughout various models and various projects. encrypted_attributes, in association with the encrypted_strings library, helps make encrypting ActiveRecord attributes easier by automating the process.

The options that encrypts takes includes all of the encryption options for the specific type of cipher being used from the encrypted_strings library. Therefore, if setting the key for asymmetric encryption, this would be passed into the encrypts method. Examples of this are show in the Usage section.

Usage¶ ↑

Encryption Modes¶ ↑

SHA, symmetric, and asymmetric encryption modes are supported (default is SHA):

class User < ActiveRecord::Base
  encrypts :password, :salt => 'secret'
  # encrypts :password, :mode => :symmetric, :password => 'secret'
  # encrypts :password, :mode => :asymmetric, :public_key_file => '/keys/public', :private_key_file => '/keys/private'
end

Dynamic Configuration¶ ↑

The encryption configuration can be dynamically set like so:

class User < ActiveRecord::Base
  encrypts :password, :mode => :sha do |user|
    {:salt => "#{user.login}-#{Time.now}", :embed_salt => true}
  end
end

In this case, the salt and password values are combined and stored in the attribute being encrypted. Therefore, there’s no need to add a second column for storing the salt value.

To store the dynamic salt in a separate column:

class User < ActiveRecord::Base
  encrypts :password, :mode => :sha, :before => :create_salt do |user|
    {:salt => user.salt}
  end

  def create_salt
    self.salt = "#{login}-#{Time.now}"
  end
end

Targeted Encryption¶ ↑

If you want to store the encrypted value in a different attribute than the attribute being encrypted:

class User < ActiveRecord::Base
  encrypts :password, :to => :crypted_password
end

Conditional Encryption¶ ↑

Like ActiveRecord validations, encrypts can take :if and :unless parameters that determine whether the encryption should occur. For example,

class User < ActiveRecord::Base
  encrypts :password, :if => lambda {Rails.env != 'development'}
end

Additional information¶ ↑

For more examples of actual migrations and models that encrypt attributes, see the actual API and unit tests. Also, see encrypted_strings for more information about the various options that can be passed in.

Testing¶ ↑

Before you can run any tests, the following gem must be installed:

• plugin_test_helper

To run against a specific version of Rails:

rake test RAILS_FRAMEWORK_ROOT=/path/to/rails

Dependencies¶ ↑

• Rails 2.1 or later

• encrypted_strings