README

This Bundle provides a Symfony2 password encoder service that uses scrypt for password encoding.

Why you should use scrypt

The scrypt key derivation function is designed to be far more secure against hardware brute-force attacks than alternative functions such as PBKDF2 or bcrypt.

The designers of scrypt estimate that on modern (2009) hardware, if 5 seconds are spent computing a derived key, the cost of a hardware brute-force attack against scrypt is roughly 4000 times greater than the cost of a similar attack against bcrypt (to find the same password), and 20000 times greater than a similar attack against PBKDF2.

But I'm already using Bcrypt!

Installation

Add this to your composer.json:

{
    "require": {
        "usu/scrypt-password-encoder-bundle": "dev-master"
    }
}

Then run:

$ composer update usu/scrypt-password-encoder-bundle

Add the bundle in app/AppKernel.php:

$bundles = array(
    // ...
    new Usu\ScryptPasswordEncoderBundle\UsuScryptPasswordEncoderBundle(),
);

And, finally, set the encoder in app/config/security.yml:

security:
    encoders:
        Symfony\Component\Security\Core\User\User:
            id: security.encoder.scrypt

Or, if you are using the excellent FOSUserBundle:

security:
    encoders:
        FOS\UserBundle\Model\UserInterface:
          id: security.encoder.scrypt

Configuration

You can change the default bundle values (shown below) by adding the following to your config.yml file:

usu_scrypt_password_encoder:
    cpu_cost: 2048
    memory_cost: 4
    parallelization_cost: 1
    key_length: 64

Changing any of the above parameters will result in a different key (auto updating of old passwords is not currently supported).

The parameter key_length determines the size in bytes of the derived key; eg: a 64 bytes key will result in a 88 characters string after the automatic base64_encode.

Please refer to the original documentation for additional informnation.

Testing

This bundle is fully tested with PHPUnit.

Go to the root folder, install the dev dependencies with composer, and then run the phpunit test suite

$ composer --dev install
$ ./vendor/bin/phpunit

License

This bundle is released under the MIT license. See the complete license in the bundle:

Resources/meta/LICENSE

Acknowledgements

I would like to thank elnur for creating the great ElnurBlowfishPasswordEncoderBundle that inspired me to release this and pbhogan from which I borrowed the "Why you should use scrypt" readme section.