<?php

/**

 * Desc: Aes 加解密 php7.1+

 * Class: Aes

 * Package: app\common\lib

 * User: manzb

 * Date: 2018/10/18 17:30

 */

namespace app\common\lib;

class Aes

{

    private $iv = '';

    private $key = '';

    private $method = '';

    function __construct ()

    {

        $aes = config('admin.aes');

        /**

         * $aes 内容

            'aes' => [

                'key' => '309w4wb42104160d2g6806lv1ki60f98',//aes加密盐

                'method' => 'AES-256-CBC',//加密方式

                'hex' => '00000000000000000000000000000000',//生成iv参数用,貌似是为了安卓ios相互兼容取的这个值

            ],
           可根据每个用户账号的不同设置不同的key字段

         */

        $this->method = $aes['method'];

        $this->key = hash('sha256', $aes['key'], true);

        $this->iv = $this->hex2iv($aes['hex']);

    }

    /**

     * 加密

     * @param $str

     * @return string

     */

    public function encrypt ($str)

    {

        $encrypt = openssl_encrypt($str, $this->method, $this->key, OPENSSL_RAW_DATA, $this->iv);

        return base64_encode($encrypt);

    }

    /**

     * 解密

     * @param $str

     * @return string

     */

    public function decrypt ($str)

    {

        $decrypted = openssl_decrypt(base64_decode($str), $this->method, $this->key, OPENSSL_RAW_DATA, $this->iv);

        return $decrypted;

    }

    /**

     * 生成iv参数

     * @param $hex

     * @return string

     */

    private function hex2iv ($hex)

    {

        $iv = '';

        for ($i = 0; $i < strlen($hex) - 1; $i += 2) {

            $iv .= chr(hexdec($hex[$i] . $hex[$i + 1]));

        }

        return $iv;

    }

}