Symfony2 - Change encoders for existing users - php

Question

If you have an existing code base with users and their passwords, how can you change the password encoder and have users' passwords update?
In other words, let's say all user passwords are in MD5 and you want to transition to PBKDF2. The common strategy is to simply re-hash the password whenever the user logs in next.
However, I'm not sure how to do this in Symfony. Would it be done in the login controller? Or is there a way to do it in the EncoderInterface object?

Answer 1

Check out this blog... seems like this is what you're looking for...
How to change the way Symfony2 encodes passwords
You need to extend MessageDigestPasswordEncoder class, overwrite its methods and copy that class to the Security folder in your bundle (create one if not exist)
Check out the following example of how to extend MessageDigestPasswordEncoder
use Symfony\Component\Security\Core\Encoder\MessageDigestPasswordEncoder as BaseMessageDigestPasswordEncoder;
class MessageDigestPasswordEncoder extends BaseMessageDigestPasswordEncoder
{
private $algorithm;
private $encodeHashAsBase64;
public function __construct($algorithm = 'sha512', $encodeHashAsBase64 = true, $iterations = 5000)
{
$this->algorithm = $algorithm;
$this->encodeHashAsBase64 = $encodeHashAsBase64;
$this->iterations = $iterations;
}
protected function mergePasswordAndSalt($password, $salt)
{
if (empty($salt)) {
return $password;
}
return $salt.$password; // or do whatever you need with the password and salt
}
public function encodePassword($raw, $salt)
{
// this is the original code from the extended class, change it as needed
if (!in_array($this->algorithm, hash_algos(), true)) {
throw new \LogicException(sprintf('The algorithm "%s" is not supported.', $this->algorithm));
}
$salted = $this->mergePasswordAndSalt($raw, $salt);
$digest = hash($this->algorithm, $salted, true);
// "stretch" hash
for ($i = 1; $i < $this->iterations; $i++) {
$digest = hash($this->algorithm, $digest.$salted, true);
}
return $this->encodeHashAsBase64 ? base64_encode($digest) : bin2hex($digest);
}
}
After you have your class ready update your config.yml
# app/config/config.yml
# ...
parameters:
security.encoder.digest.class: Ens\TestBundle\Security\MessageDigestPasswordEncoder