微信视频号消息推送api获取解密后的明文(json格式)_微信视频号评论抓取信息

/**
     * 检验消息的真实性，并且获取解密后的明文.
     * @param $msgSignature string 签名串，对应URL参数的msg_signature
     * @param $timestamp string 时间戳 对应URL参数的timestamp
     * @param $nonce string 随机串，对应URL参数的nonce
     * @param $postData string 密文，对应POST请求的数据
     * @param &$msg string 解密后的原文，当return返回0时有效
     * @param $appId string 视频号appid
     *
     * @return int 成功0，失败返回对应的错误码
     */
    public function decryptMPrpcryptsg($msgSignature, $timestamp, $nonce, $postData, &$msg, $appid)
    {
        $SHIPIN_Token = 'xxxxx';
        $SHIPIN_EncodingAESKey = 'xxxxxxxxxxxxxxxxxxxxxxx';
        if (strlen($SHIPIN_EncodingAESKey) != 43) {
            return false;
        }
 
        $array[] = 0;
        $array[] = $postData['Encrypt'];
        $array[] = $postData['ToUserName'];
 
        $ret = $array[0];
 
        if ($ret != 0) {
            return $ret;
        }
 
        if ($timestamp == null) {
            $timestamp = time();
        }
 
        $encrypt     = $array[1];
        $touser_name = $array[2];
 
        //验证安全签名
        $array = $this->ShiPingetSHA1($SHIPIN_Token, $timestamp, $nonce, $encrypt);
        $ret   = $array[0];
        if ($ret != 0) {
            return $ret;
        }
        $signature = $array[1];
        if ($signature != $msgSignature) {
            return false;
        }
        $result = $this->ShiPindecrypt($encrypt, $appId,$SHIPIN_EncodingAESKey);
        // dump($result);die;
        if ($result[0] != 0) {
            return $result[0];
        }
        $msg = $result[1];
        return $msg;
    }
    /**
     * 用SHA1算法生成安全签名
     * @param string $token 票据
     * @param string $timestamp 时间戳
     * @param string $nonce 随机字符串
     * @param string $encrypt 密文消息
     */
    public function ShiPingetSHA1($token, $timestamp, $nonce, $encrypt_msg)
    {
        //排序
        try {
            $array = array($encrypt_msg, $token, $timestamp, $nonce);
            sort($array, SORT_STRING);
            $str = implode($array);
            return array(0, sha1($str));
        } catch (Exception $e) {
           return false;
        }
    }
    /**
     * 对密文进行解密
     * @param string $encrypted 需要解密的密文
     * @return string 解密得到的明文
     */
    public function ShiPindecrypt($encrypted, $appid,$key)
    {
        $key = base64_decode($key . "=");
        try {
            //使用BASE64对需要解密的字符串进行解码
            $ciphertext_dec = base64_decode($encrypted);
            $iv = substr($key, 0, 16);
            $decrypted = openssl_decrypt($ciphertext_dec, 'AES-256-CBC', $key, OPENSSL_RAW_DATA|OPENSSL_ZERO_PADDING, $iv);
        } catch (Exception $e) {
           return false;
        }
        try {
            //去除补位字符
            $result = $this->ShiPindecode($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 $e;
            return false;
        }
        if ($from_appid != $appid)
            return false;
        return array(0, $xml_content);
    }
    /**
     * 对解密后的明文进行补位删除
     * @param decrypted 解密后的明文
     * @return 删除填充补位后的明文
     */
    function ShiPindecode($text)
    {
        $pad = ord(substr($text, -1));
        if ($pad < 1 || $pad > 32) {
            $pad = 0;
        }
        return substr($text, 0, (strlen($text) - $pad));
    }