ActiveEncryption transparently encrypt (and decrypt!) attributes. It works with any class, but it's primarly intended to be used with ActiveRecord models. Under the hood, it doesn't reinvent the wheel and uses the tried and tested ActiveSupport::MessageEncryptor.
Add this line to your application's Gemfile:
gem 'active_encryption'
And then execute:
bundle
Or install it yourself as:
gem install active_encryption
ActiveEncryption is cryptographically signed. To be sure the gem you install hasn’t been tampered with:
Add my public key (if you haven’t already) as a trusted certificate
gem cert --add <(curl -Ls https://raw.github.com/Zircode/active_encryption/master/certs/garnu.pem)
gem install active_encryption -P MediumSecurity
The MediumSecurity
trust profile will verify signed gems, but allow the
installation of unsigned dependencies.
This is necessary because not all of dependencies are signed, so we cannot use
HighSecurity
.
ActiveEncryption works with Ruby on Rails 5.0 or higher.
Run the generator:
rails generate active_encryption:install
The generator creates two files:
- an initializer:
config/initializers/active_encryption.rb
- a encryption setting YAML file:
config/encryption_settings.yml
class User
encrypted_attr :ssn
end
Or if you're using ActiveRecord:
class User < ApplicationRecord
encrypted_attr :ssn
end
In this example, ActiveEncryption assumes that you have an attribute
ssn_encrypted
.
Therefore, you might need a database migration:
class CreateUsers < ActiveRecord::Migration[5.0]
def change
create_table :users do |t|
t.string :ssn_encrypted
t.timestamps
end
end
end
When storing your encrypted data, please consider the length requirements of the database column where you're storing the encrypted data.
If you're using Rails, the generator created an initializer
config/initializers/active_encryption.rb
, otherwise you need to create
similar file to configure ActiveEncryption:
# frozen_string_literal: true
ActiveEncryption.configure do |config|
# Store containing the encryption settings
# Use "config/encryption_settings.yml" to store the settings:
config.encryption_setting_store =
ActiveEncryption::EncryptionSetting::YamlStore.new(
'/path/encryption_settings.yml' # CHANGE ME
)
# ID of the encryption setting to use by default:
config.default_encryption_setting_id = :default
end
You also need a encryption_settings.yml
file:
# WARNING: Changing these encryption settings prevents the decryption
# of already encrypted data.
# Default encryption setting
default:
# secret: must be a cryptographically random string.
# The secret is hashed with PBKDF2 to generate the encryption key.
#
# You can generate one with:
# - "rails secret"
# - SecureRandom.hex(64)
# - or, SecureRandom.urlsafe_base64(64)
#
## WARNING ##
# The secret value should NOT be stored in this file directly.
# You should instead refer to where the secret value is stored
# e.g. refer to Rails credentials/secrets, an environment variable or
# a KMS/HSM, etc.
secret: <%= ENV['SECRET_KEY'] %>
# Salt used to generate the encryption key based on the secret
secret_salt: 'ActiveEncryption salt: RANDOM_SALT' # CHANGE ME
# Number of iterations for PBKDF2 on the secret.
secret_iterations: 65536
# Cipher to use. Can be any cipher returned by OpenSSL::Cipher.ciphers.
cipher: aes-256-gcm
# Digest to use to sign. Default is SHA1. Recommended is SHA256.
# Ignored when using an AEAD cipher like 'aes-256-gcm'.
digest: SHA256
encrypted_attr
accepts options to override the settings in
encryption_settings.yml
.
For example, you can override the secret
and cipher
with options:
encrypted_attr :ssn, secret: 'some secret', cipher: 'aes-128-gcm'
The following attributes are configurable in an encryption setting:
Attribute | Description | Default value |
---|---|---|
cipher |
String with the encryption cipher to use. Can be any cipher returned by OpenSSL::Cipher.ciphers. | 'aes-256-gcm' |
digest |
String with the digest to use to sign. Ignored when using an AEAD cipher like 'aes-256-gcm'. | 'SHA1' |
id |
Unique ID to identify an encryption setting. It can be an Integer, String, or Symbol. | nil |
key |
Cryptographicaly random binary string of the exact size required by the cipher. E.g. 'aes-256-gcm' requires 32 bytes (256 bits). Can be generated with SecureRandom.bytes(32) . It is STRONGLY recommended NOT to set this directly but to use a secret for key derivation. |
nil |
purpose |
Confines the encrypted attribute to a specific purpose. See https://api.rubyonrails.org/classes/ActiveSupport/MessageEncryptor.html | nil |
secret |
String used to derive an encryption key with PBKDF2. Can be generated with SecureRandom.hex(64) or SecureRandom.urlsafe_base64(64) . |
nil |
secret_iterations |
Number of iterations of PBKDF2 to derive the key from the secret. See https://api.rubyonrails.org/classes/ActiveSupport/KeyGenerator.html | 65536 |
secret_salt |
Salt for PBKDF2 to derive the key from the secret. | 'ActiveEncryption default key salt' |
serializer |
Object serializer to use. E.g.: 'YAML'. | Marshal |
Keys or secrets must NEVER be stored in version control (e.g. git) or in the database in an unencrypted form.
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. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the Contributor Covenant code of conduct.
The gem is available as open source under the terms of the MIT License.
Everyone interacting in the ActiveEncryption project’s codebases, issue trackers, chat rooms and mailing lists is expected to follow the code of conduct.