<"\0") : ''.$result;
   } 
  } 
  return $ret; 
 } 
 // 私有方法 
 /**
  * 检测填充类型
  * 加密只支持PKCS1_PADDING
  * 解密支持PKCS1_PADDING和NO_PADDING
  * 
  * @param int 填充模式
  * @param string 加密en/解密de
  * @return bool
  */ 
 private function _checkPadding($padding, $type){
  if ($type == 'en'){ 
   switch ($padding){ 
    case OPENSSL_PKCS1_PADDING: 
     $ret = true; 
     break; 
    default: 
     $ret = false; 
   } 
  } else { 
   switch ($padding){ 
    case OPENSSL_PKCS1_PADDING: 
    case OPENSSL_NO_PADDING: 
     $ret = true; 
     break; 
    default: 
     $ret = false; 
   } 
  } 
  return $ret; 
 } 
 private function _encode($data, $code){ 
  switch (strtolower($code)){ 
   case 'base64': 
    $data = base64_encode(''.$data);
    break; 
   case 'hex': 
    $data = bin2hex($data); 
    break; 
   case 'bin': 
   default: 
  } 
  return $data; 
 } 
 private function _decode($data, $code){ 
  switch (strtolower($code)){ 
   case 'base64': 
    $data = base64_decode($data); 
    break; 
   case 'hex': 
    $data = $this->_hex2bin($data); 
    break; 
   case 'bin': 
   default: 
  } 
  return $data; 
 } 
 private function _getPublicKey($file){ 
  $key_content = $this->_readFile($file);
  if ($key_content){ 
   $this->pubKey = openssl_get_publickey($key_content);
  } 
 } 
 private function _getPrivateKey($file){ 
  $key_content = $this->_readFile($file); 
  if ($key_content){ 
   $this->priKey = openssl_get_privatekey($key_content);
  }
 }
 private function _readFile($file){
  $ret = false;
  if (!file_exists($file)){
   $this->_error("The file {$file} is not exists");
  } else {
   $ret = file_get_contents($file);
  }
  return $ret;
 } 
 private function _hex2bin($hex = false){ 
  $ret = $hex !== false && preg_match('/^[0-9a-fA-F]+$/i', $hex) "H*", $hex) : false;
  return $ret; 
 } 
}

<"rsa.php"; 
echo '<pre>'; 
$a = isset($_GET['a']) ? $_GET['a'] : '测试123'; 
////////////////////////////////////// 
$pubfile = 'E:\ssl\cert\pwd.crt'; 
$prifile = 'E:\ssl\cert\pwd.pem'; 
$m = new RSA($pubfile, $prifile); 
$x = $m->sign($a); 
$y = $m->verify($a, $x); 
var_dump($x, $y); 
$x = $m->encrypt($a); 
$y = $m->decrypt($x); 
var_dump($x, $y);