检测数据是否为 serialized 序列化数据, 如果是就解开

最新推荐文章于 2024-09-30 13:45:14 发布

原创最新推荐文章于 2024-09-30 13:45:14 发布 · 900 阅读

0 ·

CC 4.0 BY-SA版权

本文介绍了一个用于检查字符串是否为已序列化的PHP数据及进行条件性反序列化的实用函数。通过两个核心函数`is_serialized`和`maybe_unserialize`，可以有效地判断并处理PHP中序列化的数据。

摘要生成于 C知道，由 DeepSeek-R1 满血版支持，前往体验 >

/**
* Unserialize value only if it was serialized.
*
* @since 2.0.0
*
* @param string $original Maybe unserialized original, if is needed.
* @return mixed Unserialized data can be any type.
*/
function maybe_unserialize( $original ) {
if ( is_serialized( $original ) ) // don't attempt to unserialize data that wasn't serialized going in
return @unserialize( $original );
return $original;
}

/**

* Check value to find if it was serialized.
*
* If $data is not an string, then returned value will always be false.
* Serialized data is always a string.
*
* @since 2.0.5
*
* @param mixed $data Value to check to see if was serialized.
* @return bool False if not serialized and true if it was.
*/
function is_serialized( $data ) {
// if it isn't a string, it isn't serialized
if ( ! is_string( $data ) )
return false;
$data = trim( $data );
if ( 'N;' == $data )
return true;
$length = strlen( $data );
if ( $length < 4 )
return false;
if ( ':' !== $data[1] )
return false;
$lastc = $data[$length-1];
if ( ';' !== $lastc && '}' !== $lastc )
return false;
$token = $data[0];
switch ( $token ) {
case 's' :
if ( '"' !== $data[$length-2] )
return false;
case 'a' :
case 'O' :
return (bool) preg_match( "/^{$token}:[0-9]+:/s", $data );
case 'b' :
case 'i' :
case 'd' :
return (bool) preg_match( "/^{$token}:[0-9.E-]+;\$/", $data );
}
return false;

}

//这个是检测,上面的好像做了些什么处理

function is_serialized_string( $data ) {
// if it isn't a string, it isn't a serialized string
if ( !is_string( $data ) )
return false;
$data = trim( $data );
$length = strlen( $data );
if ( $length < 4 )
return false;
elseif ( ':' !== $data[1] )
return false;
elseif ( ';' !== $data[$length-1] )
return false;
elseif ( $data[0] !== 's' )
return false;
elseif ( '"' !== $data[$length-2] )
return false;
else
return true;
}