1：在商户进件接口api中报错  string(59) "{"code":"PARAM_ERROR","message":"平台私钥解密失败"}"

2:用证书给需要加密的参数加的密
  方法如下
    function getEncrypt($str){
        //$str是待加密字符串
        $public_key_path = 'cert.pem';
        $public_key = file_get_contents($public_key_path);
        $encrypted = '';
        if (openssl_public_encrypt($str,$encrypted,$public_key,OPENSSL_PKCS1_OAEP_PADDING)) {
            //base64编码
            $sign = base64_encode($encrypted);
        } else {
            throw new Exception('encrypt failed');
        }
        return $sign;
    }
 （加密生成的字符串可以用私钥反向解密成原字符串）
3：调用商户进件接口api后报错 string(59) "{"code":"PARAM_ERROR","message":"平台私钥解密失败"}