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Image upload code:

 

<?php

// check user logged in
 include('db.inc.php');

require ('htmlpure/HTMLPurifier.standalone.php'); 

// Check if coming from a POST command and Cancel
    if($_SERVER['REQUEST_METHOD']=='POST'
    && $_POST['submit']=='Return to gallery')
{
// If cancelled return to index page
header('Location: gallery.php?success=5');
exit;
}

	// Check if coming from a POST command and Upload
    if($_SERVER['REQUEST_METHOD']=='POST'
    && $_POST['submit']=='Upload')
{

// File Size Check

@session_start();

$file_size = filesize($_FILES['image']['tmp_name']);
if($file_size === 0) {
	$_SESSION['msg'] = 'That was an empty file!';
	header('Location: gallery-upload.php');
	exit;
}
else if($file_size >= (2480000)) {
	$_SESSION['msg'] = 'Image size is to big. Max upload 2MB';
	header('Location: gallery-upload.php');
	exit;
}
else if(!preg_match('/(JPE?G|PNG|GIF)/i', $_FILES['image']['name'])) {
	$_SESSION['msg'] = 'Invalid image format only JPG, PNG & GIF formts';
	header('Location: gallery-upload.php');
	exit;
}
else if(strpos($_FILES['image']['name'],'php')) {
	$_SESSION['msg'] = 'Invalid image format only JPG, PNG & GIF formts.';
	header('Location: gallery-upload.php');
	exit;	   
	}
else if(substr_count($_FILES['image']['name'], '.')>1){ //check double file type
	$_SESSION['msg'] = 'Invalid image format only JPG, PNG & GIF formts..';
	header('Location: gallery-upload.php');
	exit;
}
    
   $newPath = '' . basename($_FILES['image']['name']);
   (move_uploaded_file($_FILES['image']['tmp_name'], $newPath));

// *** Include the class
include("inc/resize-class.php");

// *** Create 'random number' + 'vacation_rentals' for image name
$imagename = time() . '_' . mt_rand(1000,9999) . '_' . 'vacation_rentals' . '.jpg';
// What Directories to put the images
$largelocation = '/home/palermo/public_html/'.$siteid.'/images/';
$thumblocation = '/home/palermo/public_html/'.$siteid.'/images/thumb/';
//thumbnail location
$large = $largelocation . $imagename;
$thumb = $thumblocation . $imagename;

// *** 1) Initialise / load image
$resizeObj = new resize($newPath);
// *** 2) Resize LARGE image (options: exact, portrait, landscape, auto, crop)
$resizeObj -> resizeImage(667, 500); //was 650, 487
// *** 3) Save image + define quality
$resizeObj -> saveImage($large, 95);

// *** 4) Initialise / load image for second resize
$resizeObj = new resize($newPath);
// *** 5) Resize THUMB (options: exact, portrait, landscape, auto, crop)
$resizeObj -> resizeImage(150, 100, 'crop'); //was 220, 165
// *** 6) Save image + define quality
$resizeObj -> saveImage($thumb, 95);

// Remove file from temp Directory
unlink($newPath) ;
	// Find the highest number in the 'rank' row and add 1 
// so uploaded photos appear at end of gallery
$stmt = $db->prepare('SELECT max(rank) FROM photos');
$stmt->execute();
$e = $stmt->fetch(); 
$num = max($e);
$order = $num+1;
  // Insert image into gallery

    $config = HTMLPurifier_Config::createDefault();
    $purifier = new HTMLPurifier($config);
    $clean_html1 = $purifier->purify($_POST['description']);
  
$stmt = $db->prepare('INSERT INTO photos (siteid, description, src, rank) VALUES (?,?,?,?)');
$stmt->execute(array( (int) $siteid, $clean_html1, $imagename, $order));
    // Get the last ID to display image on upload page
  	$id_obj = $db->query("SELECT LAST_INSERT_ID()");
  	$id = $id_obj->fetch();
  	$id_obj->closeCursor();
  	// once updated return to gallery upload image page 'id' to show uploaded image on uploads page
header('Location: gallery-upload.php?success=3&id='.$id[0]);
exit;
}
else
{
// If nothing happens
header('Location: gallery-upload.php?success=5');
exit;
}
?>

Image upload code:

 

<?php

 include('db.inc.php');

require ('htmlpure/HTMLPurifier.standalone.php'); 

// Check if coming from a POST command and Cancel
    if($_SERVER['REQUEST_METHOD']=='POST'
    && $_POST['submit']=='Return to gallery')
{
// If cancelled return to index page
header('Location: gallery.php?success=5');
exit;
}

	// Check if coming from a POST command and Upload
    if($_SERVER['REQUEST_METHOD']=='POST'
    && $_POST['submit']=='Upload')
{

// File Size Check

@session_start();

$file_size = filesize($_FILES['image']['tmp_name']);
if($file_size === 0) {
	$_SESSION['msg'] = 'That was an empty file!';
	header('Location: gallery-upload.php');
	exit;
}
else if($file_size >= (2480000)) {
	$_SESSION['msg'] = 'Image size is to big. Max upload 2MB';
	header('Location: gallery-upload.php');
	exit;
}
else if(!preg_match('/(JPE?G|PNG|GIF)/i', $_FILES['image']['name'])) {
	$_SESSION['msg'] = 'Invalid image format only JPG, PNG & GIF formts';
	header('Location: gallery-upload.php');
	exit;
}
else if(strpos($_FILES['image']['name'],'php')) {
	$_SESSION['msg'] = 'Invalid image format only JPG, PNG & GIF formts.';
	header('Location: gallery-upload.php');
	exit;	   
	}
else if(substr_count($_FILES['image']['name'], '.')>1){ //check double file type
	$_SESSION['msg'] = 'Invalid image format only JPG, PNG & GIF formts..';
	header('Location: gallery-upload.php');
	exit;
}
    
   $newPath = '' . basename($_FILES['image']['name']);
   (move_uploaded_file($_FILES['image']['tmp_name'], $newPath));

// *** Include the class
include("inc/resize-class.php");

// *** Create 'random number' + 'vacation_rentals' for image name
$imagename = time() . '_' . mt_rand(1000,9999) . '_' . 'vacation_rentals' . '.jpg';
// What Directories to put the images
$largelocation = '/home/palermo/public_html/'.$siteid.'/images/';
$thumblocation = '/home/palermo/public_html/'.$siteid.'/images/thumb/';
//thumbnail location
$large = $largelocation . $imagename;
$thumb = $thumblocation . $imagename;

// *** 1) Initialise / load image
$resizeObj = new resize($newPath);
// *** 2) Resize LARGE image (options: exact, portrait, landscape, auto, crop)
$resizeObj -> resizeImage(667, 500); //was 650, 487
// *** 3) Save image + define quality
$resizeObj -> saveImage($large, 95);

// *** 4) Initialise / load image for second resize
$resizeObj = new resize($newPath);
// *** 5) Resize THUMB (options: exact, portrait, landscape, auto, crop)
$resizeObj -> resizeImage(150, 100, 'crop'); //was 220, 165
// *** 6) Save image + define quality
$resizeObj -> saveImage($thumb, 95);

// Remove file from temp Directory
unlink($newPath) ;
	// Find the highest number in the 'rank' row and add 1 
// so uploaded photos appear at end of gallery
$stmt = $db->prepare('SELECT max(rank) FROM photos');
$stmt->execute();
$e = $stmt->fetch(); 
$num = max($e);
$order = $num+1;
  // Insert image into gallery

    $config = HTMLPurifier_Config::createDefault();
    $purifier = new HTMLPurifier($config);
    $clean_html1 = $purifier->purify($_POST['description']);
  
$stmt = $db->prepare('INSERT INTO photos (siteid, description, src, rank) VALUES (?,?,?,?)');
$stmt->execute(array( (int) $siteid, $clean_html1, $imagename, $order));
    // Get the last ID to display image on upload page
  	$id_obj = $db->query("SELECT LAST_INSERT_ID()");
  	$id = $id_obj->fetch();
  	$id_obj->closeCursor();
  	// once updated return to gallery upload image page 'id' to show uploaded image on uploads page
header('Location: gallery-upload.php?success=3&id='.$id[0]);
exit;
}
else
{
// If nothing happens
header('Location: gallery-upload.php?success=5');
exit;
}
?>

while the CGI code stops  script execution it does not stop file uploads.[+1 layer of security]

 

 

no where in your code does it have an array of what extension types are disallowed(blacklist). [+1 layer of security]

 

and instead of checking images using preg_match you would be better suited using getimagesize [+1 layer of security]

 

Securing your image upload form

 

 

 

 

 

added a blacklist:

 

	$blacklist = array(".php", ".phtml", ".php3", ".php4", ".js", ".shtml", ".pl" ,".py", ".php5", ".htm", ".html", ".zip", ".exe", ".htaccess");

foreach ($blacklist as $file)
{
if(preg_match("/$file\$/i", $_FILES['image']['name']))	{
	$_SESSION['msg'] = 'blacklisted';
	header('Location: header-image.php');
	exit;  
}}

 

 

tried using getimagesize() but it just stopped all images...

 

sorry but didn't understand this bit: "while the CGI code stops  script execution it does not stop file uploads" what are you suggesting I do?

 

could try image mime types for extensions and a whitelist array of allowed extensions.

 

$allowedexts = array('gif','jpeg','jpg','png');
$extension = end(explode(".", $_FILES["image"]["name"]));
if($_FILES["image"]["type"]=="image/jpeg"|
|$_FILES["image"]["type"]=="image/gif"||$_FILES["image"]["type"]=="image/png"
&& in_array($extension,$allowedexts)){}

could try image mime types for extensions and a whitelist array of allowed extensions.

 

$allowedexts = array('gif','jpeg','jpg','png');
$extension = end(explode(".", $_FILES["image"]["name"]));
if($_FILES["image"]["type"]=="image/jpeg"|
|$_FILES["image"]["type"]=="image/gif"||$_FILES["image"]["type"]=="image/png"
&& in_array($extension,$allowedexts)){}

 

Will that be better than what I already have?

	else if(!preg_match('/(JPE?G|PNG|GIF)/i', $_FILES['image']['name'])) {
	$_SESSION['msg'] = 'Invalid image format only JPG, PNG & GIF formts';
	header('Location: header-image.php');
	exit;
}

 

I'm giving each file a new name and changing it to a .jpg..

The uploads will only be accessible after login to an individual account & are not located in the root folder

 

it is a better way to check for images versus preg_match

 

so if you only intend to allow Jpeg and GIF take out png from the array so it only allows gif ,jpeg and jpg files and if it doesn't match, to error.

$allowedexts = array('gif','jpeg','jpg');
$extension = end(explode(".", $_FILES["image"]["name"]));
if($_FILES["image"]["type"]=="image/jpeg"|
|$_FILES["image"]["type"]=="image/gif"
&& in_array($extension,$allowedexts)){ //if match JPEG/JPG or GIF run code

}else
{
//print error here
}

 

 

 

 

 

https://www.owasp.org/index.php/Unrestricted_File_Upload

 

 

just read that apparently using white and black list is a piss poor method and can both be bypassed. according to OWASP standards. not sure where to go from here.

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