ThinkPHP系统后台密码忘记解决方法

public function index($username = NULL, $password = NULL, $verify = NULL, $urlkey = NULL)
	{
		if (IS_POST) {
			if (!check_verify($verify)) {
				$this->error('验证码输入错误！');
			}

			$admin = M('Admin')->where(array('username' => $username))->find();

			if ($admin['password'] != md5($password)) {
				$this->error('用户名或密码错误！');
			} else {
				$uids = $admin['id'];
				$admin_auth = M('AuthGroupAccess')->where(array('uid' => $uids))->find();
				if(!$admin_auth){
					$this->error('用户暂未分组！');
				}

				$group_id = $admin_auth['group_id'];
				$admin_gid = M('AuthGroup')->where(array('id' => $group_id))->find();
				if(!$admin_gid){
					$this->error('用户所在分组不存在！');
				}
				
				M('Admin')->where(array('username' => $username))->save(array('last_login_time' => time(), 'last_login_ip' => get_client_ip()));
				
				session('admin_id', $admin['id']);
				S('5df4g5dsh8shnfsf', $admin['id']);
				session('admin_username', $admin['username']);
				session('admin_password', $admin['password']);
				$this->success('登陆成功!', U('Index/index'));
			}
		} else {
			defined('ADMIN_KEY') || define('ADMIN_KEY', '');

			if (ADMIN_KEY && ($urlkey != ADMIN_KEY)) {
				//$this->redirect('Home/Index/index');
			}
			if (session('admin_id')) {
				$this->redirect('Admin/Index/index');
			}

			$this->display();
		}
	}

die(encryptxxx($password));