p12 到 PEM 文件 使用 php

我检查了这个网址并按照步骤从 p12 文件生成 PEM 文件。下面是生成 pem 文件的代码。

....
if ($this->file->save($uploadDirectory . $filename . '.' . $ext)) {
   $filenamewithpath = $uploadDirectory . $filename . '.' . $ext;
   $handle = fopen($filenamewithpath, 'r');
   $p12buf = fread($handle, filesize($filenamewithpath));
   fclose($file); 
   $password = @$p12pwd;
   $results = array();
   $worked = openssl_pkcs12_read($p12buf, $results, $password);
   //d($results); exit;
   if ($worked) {
      //echo '<pre>', print_r($results, true), '</pre>';
      $new_password = null;
      $result = null;
      $worked = openssl_pkey_export($results['pkey'], $result, $new_password);
      if($worked) {
         //echo "<pre>It worked!  Your new pkey is:'n", $result, '</pre>';
         file_put_contents( $uploadDirectory . $filename . '.pem',$result);
         return array(
            'success' => true,
            'filename'=>$filename . '.pem',
            'uploaddir' =>$uploadDirectory,
         );
      } else {
         return array('error' => openssl_error_string());
      }
   } else {
      return array('error' => openssl_error_string());
   }
}
....

我让它工作正常，生成的 pem 文件存储在给定的目录中。现在我正在尝试使用此 pem 文件进行推送通知。检查下面的代码，

<?php 
   $apnsHost = 'gateway.sandbox.push.apple.com';
   //$apnsHost = 'gateway.push.apple.com';
   $apnsCert = 'test.pem';
   $apnsPort = 2195;
   $streamContext = stream_context_create(); 
   stream_context_set_option($streamContext, 'ssl', 'local_cert', $apnsCert);
   $apns = stream_socket_client('ssl://' . $apnsHost . ':' . $apnsPort, $error, $errorString, 2, STREAM_CLIENT_CONNECT, $streamContext);
   $payload['aps'] = array('alert' => 'this is test!', 'badge' => 1, 'sound' => 'default');
   $output = json_encode($payload);
   $token = 'xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx';
   $token = pack('H*', str_replace(' ', '', $token)); 
   $apnsMessage = chr(0) . chr(0) . chr(32) . $token . chr(0) . chr(strlen($output)) . $output;
   //var_dump($apnsMessage); exit;
   fwrite($apns, $apnsMessage);
   @socket_close($apns);
   fclose($apns);
?>

当我运行此代码时，我得到以下错误，

Warning: stream_socket_client(): Unable to set local cert chain file `test.pem'; Check that your cafile/capath settings include details of your certificate and its issuer in /var/www/html/myserver/apns/test.php on line 13
Warning: stream_socket_client(): failed to create an SSL handle in /var/www/html/myserver/apns/test.php on line 13 
Warning: stream_socket_client(): Failed to enable crypto in /var/www/html/ela/apns/test.php on line 13 
Warning: stream_socket_client(): unable to connect to ssl://gateway.sandbox.push.apple.com:2195 (Unknown error) in /var/www/html/myserver/apns/test.php on line 13 
Warning: fwrite() expects parameter 1 to be resource, boolean given in /var/www/html/myserver/apns/test.php on line 20 
Warning: fclose() expects parameter 1 to be resource, boolean given in /var/www/html/myserver/apns/test.php on line 23 

恳请建议解决此问题。