PHP Uploader, can't upload to specified path, getting error - php

Question

I am fairly new to PHP coding, but I am trying to do something that is quite simple.
When someone on my website uploads a picture, the image will get renamed to random numbers and moved to my directory 'uploads/'
In my script below, Everything has been working up until :
// Upload the file to your specified path.
if(move_uploaded_file($_FILES['userfile']['tmp_name'], $upload_path . $filename))
echo "Your file has been added. Redirecting in 3 seconds."; //it worked
else
echo "There was a problem uploading your file. Please try again later."; // It failed :(.
I have all of the variables defined.
not sure what the problem is here. Should I post my whole script for the uploader?
Here is the form:
<form enctype="multipart/form-data" action="uploader.php" method="POST">
<p>
<input type="hidden" name="MAX_FILE_SIZE" value="1048576" />
Choose a file to upload:
<br>(Only .jpg, .png, & .gif are allowed. Max file size = 1MB)</br></p>
<input name="uploadedfile" type="file" />
<input type="submit" value="Upload File" />
</form>
Here is my 'uploader.php'
<?php
header('Refresh: 3; URL=index.html');
$path = $_FILES['uploadedfile']['name'];
$ext = pathinfo($path, PATHINFO_EXTENSION);
//This line assigns a random number to a variable. You could also use a timestamp here if you prefer.
$ran = rand () ;
//This takes the random number (or timestamp) you generated and adds a . on the end, so it is ready of the file extension to be appended.
$ran2 = $ran.".";
//This assigns the subdirectory you want to save into... make sure it exists!
$target = "uploads/";
//This combines the directory, the random file name, and the extension
$target = $target . $ran2.$ext;
$ext = ".".$ext;
$upload_path = "uploads/";
$filename = $target;
$allowed_filetypes = array('.jpeg','.jpg','.gif','.bmp','.png'); // These will be the types of file that will pass the validation.
$max_filesize = 1048576; // Maximum filesize in BYTES (currently 0.5MB).
$filename = $_FILES['userfile']['name']; // Get the name of the file (including file extension).
// Check if the filetype is allowed, if not DIE and inform the user.
if(!in_array($ext,$allowed_filetypes))
die('The file you attempted to upload is not allowed.'.$ext);
// Now check the filesize, if it is too large then DIE and inform the user.
if(filesize($_FILES['userfile']['tmp_name']) > $max_filesize)
die('The file you attempted to upload is too large.');
// Check if we can upload to the specified path, if not DIE and inform the user.
if(!is_writable($upload_path))
die('You cannot upload to the specified directory, please CHMOD it to 777.');
// Upload the file to your specified path.
if(move_uploaded_file($_FILES['userfile']['tmp_name'], $upload_path . $filename))
echo "Your file has been added. Redirecting in 3 seconds."; //it worked
else
echo "There was a problem uploading your file. Please try again later."; // It failed :(.
?>

Answer 1

You're resetting $filename to the original name of the file, undoing all your random name generation:
$filename = $target;
$allowed_filetypes = array('.jpeg','.jpg','.gif','.bmp','.png'); // These will be the types of file that will pass the validation.
$max_filesize = 1048576; // Maximum filesize in BYTES (currently 0.5MB).
// this line circumvents the random filename generation
$filename = $_FILES['userfile']['name']; // Get the name of the file (including file extension).
Given that, I'd expect to see the above error if you upload a file with the same name twice.
Just get rid of that last $filename = .... line and see if your error goes away.

Answer 2

You try to move $_FILES['userfile']['tmp_name'] to another destination, but it seems your file is stored in $_FILES['uploadedfile']['tmp_name'] (as uploadedfile is the name of the file input in your form, and you correctly check it at the beggining of the script).
Also, I'd strongly recommend assigning all variables and using/modifying them in one place, otherwise you are vulenrable to such simple mistakes which are hard to track down.
Here's how I'd re-write your PHP code, it's a bit more clear I think:
<?php
header('Refresh: 3; URL=index.html');
//check if file uploaded correctly to server
if ($_FILES['uploadedfile']['error'] != UPLOAD_ERR_OK)
die('Some error occurred on file upload');
$filename = $_FILES['uploadedfile']['name'];
$uploadedFile = $_FILES['uploadedfile']['tmp_name'];
$ext = '.' . pathinfo($filename , PATHINFO_EXTENSION);
$upload_path = "uploads/";
//prepare random filename
do {
$newName = md5(rand().rand().rand().microtime()) . $ext;
} while (file_exists($upload_path . $newName));
$allowed_filetypes = array('.jpeg','.jpg','.gif','.bmp','.png'); // These will be the types of file that will pass the validation.
$max_filesize = 1048576; // Maximum filesize in BYTES (currently 0.5MB).
// Check if the filetype is allowed, if not DIE and inform the user.
if(!in_array($ext,$allowed_filetypes))
die('The file you attempted to upload is not allowed.'.$ext);
// Now check the filesize, if it is too large then DIE and inform the user.
if(filesize($uploadedFile) > $max_filesize)
die('The file you attempted to upload is too large.');
// Check if we can upload to the specified path, if not DIE and inform the user.
if(!is_writable($upload_path))
die('You cannot upload to the specified directory, please CHMOD it to 777.');
// Upload the file to your specified path.
if(move_uploaded_file($uploadedFile, $upload_path . $newName))
echo "Your file has been added. Redirecting in 3 seconds."; //it worked
else
echo "There was a problem uploading your file. Please try again later."; // It failed
?>