solarai/app/Casts/EncryptFixed.php

<?php

namespace App\Casts;

use Illuminate\Contracts\Database\Eloquent\CastsAttributes;

class EncryptFixed implements CastsAttributes
{
    // 암호값을 고정하기 위함
    private $iv = 'FIXED_ENCRYPT_ST';

    /**
     * Cast the given value.
     *
     * @param  \Illuminate\Database\Eloquent\Model  $model
     * @param  string  $key
     * @param  mixed  $value
     * @param  array  $attributes
     * @return mixed
     */
    public function get($model, string $key, $value, array $attributes)
    {
        if ($value !== '' && !is_null($value)) {
            try {
                $value = $this->decrypt($value);
            } catch (\Exception $e) {
                $value = null;
            }
        }

        return $value;
    }

    /**
     * Prepare the given value for storage.
     *
     * @param  \Illuminate\Database\Eloquent\Model  $model
     * @param  string  $key
     * @param  mixed  $value
     * @param  array  $attributes
     * @return mixed
     */
    public function set($model, string $key, $value, array $attributes)
    {
        if ($value !== '' && !is_null($value)) {
            try {
                $value = $this->encrypt($value);
            } catch (\Exception $e) {
                logger($e->getTraceAsString());
            }
        }

        return $value;
    }

    public function encrypt($value)
    {
        return base64_encode(openssl_encrypt($value, "AES-256-CBC", config('app.key'), 0, $this->iv));
    }

    public function decrypt($value)
    {
        return openssl_decrypt(base64_decode($value), "AES-256-CBC", config('app.key'), 0, $this->iv);
    }
}