Laravel Hashing

「ハッシュ化」とは、「元データ」をハッシュアルゴリズム（md5、sha1、sha2等）に従って、固定長のランダムに見える値に「不可逆変換」する行為
Google検索もデータをhash化してるんじゃなかったっけ。

Introduction
The Laravel Hash facade provides secure Bcrypt and Argon2 hashing for storing user passwords. If you are using the built-in LoginController and RegisterController classes that are included with your Laravel application, they will use Bcrypt for registration and authentication by default.

Tip!! Bcrypt is a great choice for hashing passwords because its “work factor” is adjustable, which means that the time it takes to generate a hash can be increased as hardware power increases.

Bcrypt、Argon2? パスワード保存に使うアルゴリズム。なるほど。
Argon2は2015年7月に開催されたパスワードハッシュ競技会（英語版）で優勝した鍵導出関数
なるほどー、面白いね、この分野。

Basic Usage
You may hash a password by calling the make method on the Hash facade:

namespace App\Http\Controllers;

use Illuminate\Http\Request;
use Illuminate\Support\Facades\Hash;
use App\Http\Controllers\Controller;

class UpdatePasswordController extends Controller
{
    /**
     * Update the password for the user.
     *
     * @param  Request  $request
     * @return Response
     */
    public function update(Request $request)
    {
        // Validate the new password length...

        $request->user()->fill([
            'password' => Hash::make($request->newPassword)
        ])->save();
    }
}

Hash::make($request->newPassword)って、ナニコレ。passwordをhash化してるってこと？
確かにDBにはハッシュ化された値です。

Adjusting The Bcrypt Work Factor
If you are using the Bcrypt algorithm, the make method allows you to manage the work factor of the algorithm using the rounds option; however, the default is acceptable for most applications:

$hashed = Hash::make('password', [
    'rounds' => 12
]);

ぬお、覚えること多すぎる。
Adjusting The Argon2 Work Factor
If you are using the Argon2 algorithm, the make method allows you to manage the work factor of the algorithm using the memory, time, and threads options; however, the defaults are acceptable for most applications:

$hashed = Hash::make('password', [
    'memory' => 1024,
    'time' => 2,
    'threads' => 2,
]);

ハッシュ化のアルゴリズム、チューニングできるんか。おもろ。

Verifying A Password Against A Hash
The check method allows you to verify that a given plain-text string corresponds to a given hash. However, if you are using the LoginController included with Laravel, you will probably not need to use this directly, as this controller automatically calls this method:

if (Hash::check('plain-text', $hashedPassword)) {
    // The passwords match...
}

Checking If A Password Needs To Be Rehashed
The needsRehash function allows you to determine if the work factor used by the hasher has changed since the password was hashed:

if (Hash::needsRehash($hashed)) {
    $hashed = Hash::make('plain-text');
}