EncryptColumn

Encrypt any column with an optional hash (using searchable: true) or conditionally (if: Proc) also has a failsafe (failsafe: true) feature to write to different db column in the database, i.e. <name>_ciphertext. This prevents users from accidentally commenting out the encrypt declaration and writing plaintext to the database.

Add this line to your application's Gemfile:

gem 'encrypt_column'

And then execute:

$ bundle

Or install it yourself as:

$ gem install encrypt_column

Specify the column to be encrypted as so (i.e. encrypt ssn column):

  encrypt :ssn

To add a <Model>.with_<field_name>(<field_value>) search method (using a hash column named <column_name>_hash or ssn_hash)

  encrypt :ssn, searchable: true

Usage like so:

  SecureTable.with_ssn('123456789')

To use a failsafe column name to prevent accidental removal of encryption specify "failsafe: true". This will store the data in a column name <column_name>_ciphertext (i.e. ssn_ciphertext) but allow for read/write access by the original column name.

  encrypt :ssn, failsafe: true

To conditionally encrypt a column you can specify an if statement like so:

  encrypt :card_number,  if: -> (x) { x.card_type == 'credit' }

Use all the options combined, like so:

  encrypt :card_number, searchable: true, failsafe: true, if -> (x) { x.card_type == 'credit' }

The gem uses the ENCRYPTION_KEY environment variable for encryption setup:

  ENV['ENCRYPTION_KEY'] = 'your_encryption_key_goes_here'

Alternatively, you can specify the encryption key as an option in the encrypt line:

  encrypt :ssn, key: 'your_encryption_key_goes_here'

and optionally a HASH_SALT if the searchable option is used.

  ENV['HASH_SALT'] = 'some_salt'

Or specify the hash salt in the encrypt line:

  encrypt :ssn, :searchable, hash_salt: 'your_hash_salt_goes_here', key: 'your_encryption_key_goes_here'

After checking out the repo, run bin/setup to install dependencies. Then, run rake spec to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.

Bug reports and pull requests are welcome on GitHub at https://github.com/danlherman/encrypt_column.

The gem is available as open source under the terms of the MIT License.