Spryker - PropelEncryptionBehavior

Seamlessly encrypt/decrypt Propel2 data fields. This library is a plugin for the Propel2 ORM framework. The library is a fork of Athens\Encryption.

For example:

// schema.xml

    <table name="my_class">
        <column name="id" type="integer" required="true" primaryKey="true" autoIncrement="true"/>

        <column name="my_data" type="varchar" size="255"/>
        <column name="my_secret_data" type="BLOB"/>
        <column name="my_searchable_data" type="varbinary" size="255"/>

        <behavior name="encryption">
            <parameter name="column_name_1" value="my_secret_data"/>
            <parameter name="searchable_column_name_1" value="my_searchable_data"/>
            <parameter name="searchable" value="false"/>
        </behavior>
    </table>

// Before any database queries:

    use Spryker\PropelEncryptionBehavior\Cipher;
    Cipher::createInstance("mysecretpassphrase");


// In your application:

    $o = new MyClass();

    $o->setMyData("Some data that will remain as plain text.");
    $o->setMySecretData("Some data that will be encrypted.");

    $o->save();

// Later:

    $o = MyClassQuery::create()->findOneByMyData("Some data that will remain as plain text.");

    echo $o->getMySecretData();
    // "Some data that will be encrypted."

    // If you need to use different passphrases in different queries:

    use Spryker\PropelEncryptionBehavior\Cipher;

    Cipher::resetInstance();
    Cipher::createInstance("mysecretpassphrase_2");

    // ... read or write data with another passphrase

Given the table definition above, the string "Some data that will be encrypted." is encrypted in memory before being sent to the database. When we retrieve MySecretData later, the ciphertext is decrypted before being returned.

Note/Tradeoff

spryker/propel-encryption-behavior breaks Propel's native search/find/sort methods on the encrypted field(s). Because the plain-texts of encrypted fields are not available to the database, no database method of search or sort can operate on these fields. A search or sort can only be accomplished by retrieving all rows, decrypting all values, and performing a search/sort on those. If you have many rows and you need to search/sort on encrypted fields, this process may be impractically slow.

Installation

composer require spryker/propel-encryption-behavior

Use

This client library provides a Cipher class and one Propel2 Behavior class.

To designate a field as encrypted in your Propel schema, set its type as VARBINARY, LONGVARBINARY or BLOB and include the encryption behavior. Parameters that define encrypted columns should contain column_name_* prefix in the name attribute. You may include multiple columns in the encryption behavior:

    <table name="my_class">
        <column name="id" type="integer" required="true" primaryKey="true" autoIncrement="true"/>

        <column name="my_data" type="varchar" size="255"/>

        <column name="my_secret_data" type="varbinary" size="255"/>
        <column name="my_secret_data2" type="varbinary" size="255"/>

        <behavior name="encryption">
            <parameter name="column_name_1" value="my_secret_data"/>
            <parameter name="column_name_2" value="my_secret_data2"/>
        </behavior>
    </table>

Then build your models and database as usual.

Before querying the database, you must initialize the Cipher class with your passphrase:

    // Intialize the cipher
    Cipher::createInstance($my_passphrase);

The argument $my_passphrase should be a string of random characters. A length of 32-64 characters is appropriate for your passphrase. Because the cipher is initialized with every page load, the passphrase must be stored on your server in a location accessible to PHP. However, the passphrase should not be in a file which is viewable to web-visitors, and it almost certainly should not be included in your source/version control (git, scm, etc.).

That's it! The class setters for MySecretData and MySecretData2 now seamlessly encrypt their data before it is sent to the database. The class getters for MySecretData and MySecretData2 seamlessly decrypt data after retrieving it from the database.

Remember that search/find and sort are now broken for MySecretData and MySecretData2, for reasons discussed above.

Filtering

By default all encrypted columns are not searchable. It's possible to make all encrypted columns of a table searchable by setting a parameter searchable to true

    <table name="my_class">
        <column name="id" type="integer" required="true" primaryKey="true" autoIncrement="true"/>
        <column name="my_data" type="varchar" size="255"/>
        <column name="my_secret_data" type="varbinary" size="255"/>

        <behavior name="encryption">
            <parameter name="column_name_1" value="my_secret_data"/>
            <parameter name="searchable" value="true"/>
        </behavior>
    </table>

It's also possible to make a particular column as searchable using searchable_column_name_* prefix

    <table name="my_class">
        <column name="id" type="INTEGER" required="true" primaryKey="true" autoIncrement="true"/>
        <column name="my_data" type="VARCHAR" size="255"/>
        <column name="my_secret_data" type="BLOB"/>
        <column name="my_secret_searchable_data" type="VARBINARY" size="255"/>

        <behavior name="encryption">
            <parameter name="column_name_1" value="my_secret_data"/>
            <parameter name="searchable_column_name_1" value="my_secret_searchable_data"/>
        </behavior>
    </table>

Be aware: For the searchable columns will be used a fixed IV. It looses data security.