Laravel/php 7实现微信开放平台消息加解密

PHP5.6升级到PHP7以后，析构函数（构造函数）语法规则改变，由以前的与class同名，在WXBizMsgCrypt.php更改WXBizMsgCrypt方法为__construct()；参考消息加解密说明

基础配置

申请第三方平台，这个很简单直接按照提示填写，下面的授权事件接收URL中获取的component_verify_ticket是会过期的，所以不要只获取一次，缓存起来每10分钟会发送一次，每1小时会更新一次。

获取参数

获取配置变量参数。获取component_verify_ticket

$timeStamp    =$request->timestamp;
$nonce        =$request->nonce;
$encrypt_type =$request->encrypt_type;
$msg_sign     =$request->msg_signature;
$encryptMsg   =file_get_contents('php://input');

$token = "公众平台上，开发者设置的token";
$encodingAesKey = "公众平台上，开发者设置的EncodingAESKey";
$appId = "公众平台的appId";

$pc = new WXBizMsgCrypt($token, $encodingAesKey, $appId);

$xml_tree = new \DOMDocument();
$xml_tree->loadXML($encryptMsg);
$array_e = $xml_tree->getElementsByTagName('Encrypt');
$encrypt = $array_e->item(0)->nodeValue;

$format = "<xml><ToUserName><![CDATA[toUser]]></ToUserName><Encrypt><![CDATA[%s]]></Encrypt></xml>";

$from_xml = sprintf($format, $encrypt);

$msg = '';

$errCode = $pc->decryptMsg($msg_sign, $timeStamp, $nonce, $from_xml, $msg);

if ($errCode == 0) {

$xml = new \DOMDocument();
$xml->loadXML($msg);
$array_e = $xml->getElementsByTagName('ComponentVerifyTicket');

$component_verify_ticket = $array_e->item(0)->nodeValue;

$wechat_verifyticket = array(
'component_verify_ticket'    => $component_verify_ticket,
'uptime'                    => time());

Redis::set('wechat_verifyticket',$wechat_verifyticket);

return true;
}else{
$wechat_verifyticket = array(
'component_verify_ticket'    => $component_verify_ticket,
'uptime'                    => time());

Redis::set('wechat_verifyticket',$wechat_verifyticket);
return false;
}

修改PKCS7Encoder.php文件

<?php

include_once "errorCode.php";

/**
 * PKCS7Encoder class
 *
 * 提供基于PKCS7算法的加解密接口.
 */
class PKCS7Encoder
{
    public static $block_size = 32;

    /**
     * 对需要加密的明文进行填充补位
     * @param $text 需要进行填充补位操作的明文
     * @return 补齐明文字符串
     */
    function encode($text)
    {
        $block_size = PKCS7Encoder::$block_size;
        $text_length = strlen($text);
        //计算需要填充的位数
        $amount_to_pad = PKCS7Encoder::$block_size - ($text_length % PKCS7Encoder::$block_size);
        if ($amount_to_pad == 0) {
            $amount_to_pad = PKCS7Encoder::block_size;
        }
        //获得补位所用的字符
        $pad_chr = chr($amount_to_pad);
        $tmp = "";
        for ($index = 0; $index < $amount_to_pad; $index++) {
            $tmp .= $pad_chr;
        }
        return $text . $tmp;
    }

    /**
     * 对解密后的明文进行补位删除
     * @param decrypted 解密后的明文
     * @return 删除填充补位后的明文
     */
    function decode($text)
    {

        $pad = ord(substr($text, -1));
        if ($pad < 1 || $pad > 32) {
            $pad = 0;
        }
        return substr($text, 0, (strlen($text) - $pad));
    }

}

/**
 * Prpcrypt class
 *
 * 提供接收和推送给公众平台消息的加解密接口.
 */
class Prpcrypt
{
    public $key;

    function Prpcrypt($k)
    {
        $this->key = base64_decode($k . "=");
    }

    /**
     * 对明文进行加密
     * @param string $text 需要加密的明文
     * @return string 加密后的密文
     */
    public function encrypt($text, $appid)
    {

        try {
            $random = $this->getRandomStr();
            $text = $random . pack("N", strlen($text)) . $text . $appid;
            $iv = substr($this->key, 0, 16);
            $pkc_encoder = new PKCS7Encoder;
            $text = $pkc_encoder->encode($text);
            $encrypted = openssl_encrypt($text, 'AES-256-CBC', $this->key, OPENSSL_RAW_DATA|OPENSSL_ZERO_PADDING, $iv);

            //使用BASE64对加密后的字符串进行编码
            return array(ErrorCode::$OK, base64_encode($encrypted));
        } catch (\Exception $e) {
            return array(ErrorCode::$EncryptAESError, null);
        }
    }

    /**
     * 对密文进行解密
     * @param string $encrypted 需要解密的密文
     * @return string 解密得到的明文
     */
    public function decrypt($encrypted, $appid)
    {

        try {
            $ciphertext_dec = base64_decode($encrypted);
            $iv = substr($this->key, 0, 16);
            $decrypted = openssl_decrypt($ciphertext_dec, 'AES-256-CBC', $this->key, OPENSSL_RAW_DATA|OPENSSL_ZERO_PADDING, $iv);
        } catch (\Exception $e) {
            return array(ErrorCode::$DecryptAESError, null);
        }

        try {
            //去除补位字符
            $pkc_encoder = new PKCS7Encoder;
            $result = $pkc_encoder->decode($decrypted);
            //去除16位随机字符串,网络字节序和AppId
            if (strlen($result) < 16)
                return "";
            $content = substr($result, 16, strlen($result));
            $len_list = unpack("N", substr($content, 0, 4));
            $xml_len = $len_list[1];
            $xml_content = substr($content, 4, $xml_len);
            $from_appid = substr($content, $xml_len + 4);
        } catch (\Exception $e) {
            //print $e;
            return array(ErrorCode::$IllegalBuffer, null);
        }
        if ($from_appid != $appid)
            return array(ErrorCode::$ValidateAppidError, null);
        return array(0, $xml_content);

    }

    /**
     * 随机生成16位字符串
     * @return string 生成的字符串
     */
    function getRandomStr()
    {

        $str = "";
        $str_pol = "ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789abcdefghijklmnopqrstuvwxyz";
        $max = strlen($str_pol) - 1;
        for ($i = 0; $i < 16; $i++) {
            $str .= $str_pol[mt_rand(0, $max)];
        }
        return $str;
    }

}

?>

参考: php7以上 不支持mcrypt_module_open方法问题