//查询入口
    public function testOp(){
        $domain = ''; //网站域名
        $cert_info = $this->get_cert_info($domain);
        $dn = $cert_info['subject']['CN']; //证书保护域名
        $validFrom_time_t = date('Y-m-d H:i:s', $cert_info['validFrom_time_t']); //证书开始时间
        $validTo_time_d = date('Y-m-d H:i:s', $cert_info['validTo_time_t']); //证书结束时间
 
        echo "+-证书保护域名：" . $dn . " -+------------------+\n";
        echo "+-证书开始时间：" . $validFrom_time_t . " -+------------------+\n";
        echo "+-证书结束时间：" . $validTo_time_d . " -+------------------+\n";
        echo '<pre>';print_r($cert_info);
    }
    public function get_cert_info($domain){
        set_time_limit(100);
        $context = stream_context_create(['ssl' => [
            'capture_peer_cert' => true,
            'capture_peer_cert_chain' => true,
            ],
        ]);
 
        $client = stream_socket_client("ssl://".$domain.":443", $errno, $errstr, 30, STREAM_CLIENT_CONNECT, $context);
        if($client==false) {
            return false;
        }
        $params = stream_context_get_params($client);
        $cert = $params['options']['ssl']['peer_certificate'];
        $cert_info = openssl_x509_parse($cert);
        return $cert_info;
    }