【发布时间】：2013-01-21 08:02:11
【问题描述】：
我在互联网上找到了以下代码，用于在 php 中安全上传图片。
我想知道它涵盖了图片上传中所有可能的攻击方式。
define('MAX_SIZE_EXCEDED', 101);
define('UPLOAD_FAILED', 102);
define('NO_UPLOAD', 103);
define('NOT_IMAGE', 104);
define('INVALID_IMAGE', 105);
define('NONEXISTANT_PATH', 106);
class ImgUploader
{
var $tmp_name;
var $name;
var $size;
var $type;
var $error;
var $width_orig;
var $height_orig;
var $num_type;
var $errorCode = 0;
var $allow_types = array(IMAGETYPE_GIF, IMAGETYPE_JPEG, IMAGETYPE_PNG);
function __construct($fileArray)
{
foreach($fileArray as $key => $value)
{
$this->$key = $value;
}
if($this->error > 0)
{
switch ($this->error)
{
case 1: $this->errorCode = MAX_SIZE_EXCEDED; break;
case 2: $this->errorCode = MAX_SIZE_EXCEDED; break;
case 3: $this->errorCode = UPLOAD_FAILED; break;
case 4: $this->errorCode = NO_UPLOAD; break;
}
}
if($this->errorCode == 0)
{
$this->secure();
}
}
function secure()
{
//$this->num_type = exif_imagetype($this->tmp_name);
@list($this->width_orig, $this->height_orig, $this->num_type) = getimagesize($this->tmp_name);
if(filesize($this->tmp_name) > 1024*1024*1024*5) // allows for five megabytes. Change this number if need be.
{
$this->errorCode = MAX_SIZE_EXCEDED;
return false;
}
if (!$this->num_type)
{
$this->errorCode = NOT_IMAGE;
return false;
}
if(!in_array($this->num_type, $this->allow_types))
{
$this->errorCode = INVALID_IMAGE;
return false;
}
}
function getError()
{
return $this->errorCode;
}
function upload_unscaled($folder, $name)
{
return $this->upload($folder, $name, "0", "0");
}
function upload($folder, $name, $width, $height, $scaleUp = false)
{
// $folder is location to be saved
// $name is name of file, without file extention
// $width is desired max width
// $height is desired max height
if($this->errorCode > 0)
return false;
// deal with sizing
// if image is small enough to not scale, or upload_unscaled() is called, don't scale
if((!$scaleUp && ($width > $this->width_orig && $height > $this->height_orig)) || ($width === "0" && $height === "0"))
{
$width = $this->width_orig;
$height = $this->height_orig;
}
else
{
// if height diff is less than width dif, calc height
if(($this->height_orig - $height) <= ($this->width_orig - $width))
$height = ($width / $this->width_orig) * $this->height_orig;
else
$width = ($height / $this->height_orig) * $this->width_orig;
}
// Resample
switch($this->num_type)
{
case IMAGETYPE_GIF: $image_o = imagecreatefromgif($this->tmp_name); $ext = '.gif'; break;
case IMAGETYPE_JPEG: $image_o = imagecreatefromjpeg($this->tmp_name); $ext = '.jpg'; break;
case IMAGETYPE_PNG: $image_o = imagecreatefrompng($this->tmp_name); $ext = '.png'; break;
}
$filepath = $folder.(substr($folder,-1) != '/' ? '/' : '');
if(is_dir($_SERVER['DOCUMENT_ROOT'].$filepath))
$filepath .= $name.$ext;
else
{
$this->errorCode = NONEXISTANT_PATH;
imagedestroy($image_o);
return false;
}
$image_r = imagecreatetruecolor($width, $height);
imagecopyresampled($image_r, $image_o, 0, 0, 0, 0, $width, $height, $this->width_orig, $this->height_orig);
switch($this->num_type)
{
case IMAGETYPE_GIF: imagegif($image_r, $_SERVER['DOCUMENT_ROOT'].$filepath); break;
case IMAGETYPE_JPEG: imagejpeg($image_r, $_SERVER['DOCUMENT_ROOT'].$filepath); break;
case IMAGETYPE_PNG: imagepng($image_r, $_SERVER['DOCUMENT_ROOT'].$filepath); break;
}
imagedestroy($image_o);
imagedestroy($image_r);
return '/'.$filepath;
}
}
我还在“images”文件夹中存储了一个 .htaccess 文件，该文件会关闭文件脚本，因此没有人可以执行照片文件夹中的脚本。
<Files ^(*.jpg)>
order deny,allow
deny from all
</Files>
Options -Indexes
Options -ExecCGI
AddHandler cgi-script .php .php3 .php4 .php5 .phtml .pl .py .jsp .asp .htm .shtml .sh .cgi
出于安全原因，这样做就足够了，或者我必须采取一些其他措施来保护我的代码和网站。
【问题讨论】：
-
你自己试过这个代码吗？你有使用示例吗？
标签： php image-uploading