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file_check_location

  1. drupal
    1. 4.7 file.inc
    2. 5 file.inc
    3. 6
Versions
4.7 – 6 file_check_location($source, $directory = '')

Check if a file is really located inside $directory. Should be used to make sure a file specified is really located within the directory to prevent exploits.

<?php
  // Returns FALSE:
  file_check_location('/www/example.com/files/../../../etc/passwd', '/www/example.com/files');
?>

Parameters

$source A string set to the file to check.

$directory A string where the file should be located.

Return value

0 for invalid path or the real path of the source.

Related topics

File interface
Common file handling functions.

▸ 1 function calls file_check_location()

▾ 1 function calls file_check_location()

file_create_path in drupal/includes/file.inc
Make sure the destination is a complete path and resides in the file system directory, if it is not prepend the file system directory.

Code

drupal/includes/file.inc, line 181

<?php
function file_check_location($source, $directory = '') {
  $check = realpath($source);
  if ($check) {
    $source = $check;
  }
  else {
    // This file does not yet exist
    $source = realpath(dirname($source)) . '/' . basename($source);
  }
  $directory = realpath($directory);
  if ($directory && strpos($source, $directory) !== 0) {
    return 0;
  }
  return $source;
}
?>