This is the concern mixed in Active Record models to make them encryptable. It adds the encrypts attribute declaration, as well as the API to encrypt and decrypt records.
# File activerecord/lib/active_record/encryption/encryptable_record.rb, line 129
def add_length_validation_for_encrypted_columns
encrypted_attributes&.each do |attribute_name|
validate_column_size attribute_name
end
end # File activerecord/lib/active_record/encryption/encryptable_record.rb, line 148 def ciphertext_for(attribute_name) read_attribute_before_type_cast(attribute_name) end
Returns the ciphertext for attribute_name.
# File activerecord/lib/active_record/encryption/encryptable_record.rb, line 158 def decrypt decrypt_attributes if has_encrypted_attributes? end
Decrypts all the encryptable attributes and saves the changes.
# File activerecord/lib/active_record/encryption/encryptable_record.rb, line 58
def deterministic_encrypted_attributes
@deterministic_encrypted_attributes ||= encrypted_attributes&.find_all do |attribute_name|
type_for_attribute(attribute_name).deterministic?
end
end Returns the list of deterministic encryptable attributes in the model class.
# File activerecord/lib/active_record/encryption/encryptable_record.rb, line 153 def encrypt encrypt_attributes if has_encrypted_attributes? end
Encrypts all the encryptable attributes and saves the changes.
# File activerecord/lib/active_record/encryption/encryptable_record.rb, line 84
def encrypt_attribute(name, attribute_scheme)
encrypted_attributes << name.to_sym
attribute name do |cast_type|
ActiveRecord::Encryption::EncryptedAttributeType.new scheme: attribute_scheme, cast_type: cast_type
end
preserve_original_encrypted(name) if attribute_scheme.ignore_case?
ActiveRecord::Encryption.encrypted_attribute_was_declared(self, name)
end # File activerecord/lib/active_record/encryption/encryptable_record.rb, line 143 def encrypted_attribute?(attribute_name) ActiveRecord::Encryption.encryptor.encrypted? ciphertext_for(attribute_name) end
Returns whether a given attribute is encrypted or not.
# File activerecord/lib/active_record/encryption/encryptable_record.rb, line 47
def encrypts(*names, key_provider: nil, key: nil, deterministic: false, downcase: false, ignore_case: false, previous: [], **context_properties)
self.encrypted_attributes ||= Set.new # not using :default because the instance would be shared across classes
scheme = scheme_for key_provider: key_provider, key: key, deterministic: deterministic, downcase: downcase, \
ignore_case: ignore_case, previous: previous, **context_properties
names.each do |name|
encrypt_attribute name, scheme
end
end Encrypts the name attribute.
:key_provider - Configure a KeyProvider for serving the keys to encrypt and decrypt this attribute. If not provided, it will default to ActiveRecord::Encryption.key_provider.
:key - A password to derive the key from. It's a shorthand for a :key_provider that serves derivated keys. Both options can't be used at the same time.
:key_provider - Set a :key_provider to provide encryption and decryption keys. If not provided, it will default to the key provider set with `config.key_provider`.
:deterministic - By default, encryption is not deterministic. It will use a random initialization vector for each encryption operation. This means that encrypting the same content with the same key twice will generate different ciphertexts. When set to true, it will generate the initialization vector based on the encrypted content. This means that the same content will generate the same ciphertexts. This enables querying encrypted text with Active Record. Deterministic encryption will use the oldest encryption scheme to encrypt new data by default. You can change this by setting +deterministic: { fixed: false }+. That will make it use the newest encryption scheme for encrypting new data.
:downcase - When true, it converts the encrypted content to downcase automatically. This allows to effectively ignore case when querying data. Notice that the case is lost. Use :ignore_case if you are interested in preserving it.
:ignore_case - When true, it behaves like :downcase but, it also preserves the original case in a specially designated column +original_<name>+. When reading the encrypted content, the version with the original case is served. But you can still execute queries that will ignore the case. This option can only be used when :deterministic is true.
:context_properties - Additional properties that will override Context settings when this attribute is encrypted and decrypted. E.g: encryptor:, cipher:, message_serializer:, etc.
:previous - List of previous encryption schemes. When provided, they will be used in order when trying to read the attribute. Each entry of the list can contain the properties supported by encrypts. Also, when deterministic encryption is used, they will be used to generate additional ciphertexts to check in the queries.
# File activerecord/lib/active_record/encryption/encryptable_record.rb, line 78
def global_previous_schemes_for(scheme)
ActiveRecord::Encryption.config.previous_schemes.collect do |previous_scheme|
scheme.merge(previous_scheme)
end
end # File activerecord/lib/active_record/encryption/encryptable_record.rb, line 123 def load_schema! super add_length_validation_for_encrypted_columns if ActiveRecord::Encryption.config.validate_column_size end
# File activerecord/lib/active_record/encryption/encryptable_record.rb, line 106
def override_accessors_to_preserve_original(name, original_attribute_name)
include(Module.new do
define_method name do
if ((value = super()) && encrypted_attribute?(name)) || !ActiveRecord::Encryption.config.support_unencrypted_data
send(original_attribute_name)
else
value
end
end
define_method "#{name}=" do |value|
self.send "#{original_attribute_name}=", value
super(value)
end
end)
end # File activerecord/lib/active_record/encryption/encryptable_record.rb, line 95
def preserve_original_encrypted(name)
original_attribute_name = "#{ORIGINAL_ATTRIBUTE_PREFIX}#{name}".to_sym
if !ActiveRecord::Encryption.config.support_unencrypted_data && !column_names.include?(original_attribute_name.to_s)
raise Errors::Configuration, "To use :ignore_case for '#{name}' you must create an additional column named '#{original_attribute_name}'"
end
encrypts original_attribute_name
override_accessors_to_preserve_original name, original_attribute_name
end # File activerecord/lib/active_record/encryption/encryptable_record.rb, line 70
def scheme_for(key_provider: nil, key: nil, deterministic: false, downcase: false, ignore_case: false, previous: [], **context_properties)
ActiveRecord::Encryption::Scheme.new(key_provider: key_provider, key: key, deterministic: deterministic,
downcase: downcase, ignore_case: ignore_case, **context_properties).tap do |scheme|
scheme.previous_schemes = global_previous_schemes_for(scheme) +
Array.wrap(previous).collect { |scheme_config| ActiveRecord::Encryption::Scheme.new(**scheme_config) }
end
end # File activerecord/lib/active_record/encryption/encryptable_record.rb, line 65
def source_attribute_from_preserved_attribute(attribute_name)
attribute_name.to_s.sub(ORIGINAL_ATTRIBUTE_PREFIX, "") if /^#{ORIGINAL_ATTRIBUTE_PREFIX}/.match?(attribute_name)
end Given a attribute name, it returns the name of the source attribute when it's a preserved one.
# File activerecord/lib/active_record/encryption/encryptable_record.rb, line 135
def validate_column_size(attribute_name)
if limit = columns_hash[attribute_name.to_s]&.limit
validates_length_of attribute_name, maximum: limit
end
end
© 2004–2021 David Heinemeier Hansson
Licensed under the MIT License.