custom auth and hashing laravel 5.1

I have an existing database.

users :
username => varchar
password => md5 hashing

I am new to laravel, I was try to create simple login and register from laravel docs, thats work fine, but in docs are create for laravel, now I want to create same login/register but with existing datas.

I was read some Question from How to use SHA1 encryption instead of BCrypt in Laravel 4? but I dont understand how to use it.

any adv?

sory for my bad grammer.

I'll Try to answer my question. I take it from Facebook Group Laravel Indonesia

Create directory app/libraries
Add app/libraries to composer.json

"classmap": ["database","app/libraries"],

Create MD5Hasher.php in app/libraries

<?php    
namespace App\Libraries;        
use Illuminate\Contracts\Hashing\Hasher as HasherContract;

class MD5Hasher implements HasherContract {

public function make($value, array $options = array()) {
$value = env('SALT', '').$value;
return md5($value);
}

public function check($value, $hashedValue, array $options = array()) {
return $this->make($value) === $hashedValue;
}

public function needsRehash($hashedValue, array $options = array()) {
return false;
}

}

Create MD5HashServiceProvider.php in app/libraries

<?php

namespace App\Libraries;

use Illuminate\Support\ServiceProvider;

class MD5HashServiceProvider extends ServiceProvider {

/**
* Register the service provider.
*
* @return void
*/
public function register() {
$this->app['hash'] = $this->app->share(function () {
return new MD5Hasher();
});

}

/**
* Get the services provided by the provider.
*
* @return array
*/
public function provides() {
return array('hash');
}

}

in config/app.php

Find Illuminate\Hashing\HashServiceProvider::class,

Change to App\Libraries\MD5HashServiceProvider::class,

in AuthController.php

Add protected $username = 'username';

return Validator::make($data, [
            //'name' => 'required|max:255',
            'username' => 'required',
            'password' => 'required|confirmed|min:5',
        ]);

return User::create([
            //'name' => $data['name'],
            'username' => $data['username'],
            'password' => md5($data['password']),
        ]);

in App\Users.php

Change protected $fillable = ['name', 'email', 'password'];

To protected $fillable = ['username', 'password'];
Don't forget to run composer dumpautoload