source: app/Http/Middleware/CheckPermission.php@ c08466c

<?php

namespace App\Http\Middleware;

use Closure;

class CheckPermission
{
    /**
     * Handle an incoming request.
     *
     * @param  \Illuminate\Http\Request  $request
     * @param  \Closure  $next
     * @return mixed
     */
    public function handle($request, Closure $next, $permission)
    {
        $user = auth()->user();

        if($user->hasPermission($permission)) {
            return $next($request);
        }

        return abort(403);
    }
}