PHP is_readable trouble with open_basedir

Question

I've recently gotten an error when I deployed an application. It used "is_readable" on a path within the include path, but one that was restricted by "open_basedir". This gave me a fatal error. Is there another function that I could use to see if a file is includable, before actually including it?

---

Edit: this works, but how do I detect if the error was because the include failed or because of some error inside the included file?

try {
 include 'somefile.php';
 $included = true; 
} catch (Exception $e) {
 // Code to run if it didn't work out
 $included = false;
}

Answer 1

You can check the value of the open_basedir rescriction (if set) using

ini_get( 'open_basedir' );

It will return the allowed path(s) or an empty string if not set.

Edit:

Checking the include path in a open_basedir restriction safe way could go something like this:

if ( strlen( ini_get( 'open_basedir' ) ) > 0 )
{
    $includeFile = 'yourInclude.php';
    $includePath = dirname( realpath( $includeFile ) );

    $baseDirs = explode( PATH_SEPARATOR, ini_get( 'open_basedir' ) );
    foreach ( $baseDirs as $dir )
    {
     if ( strstr( $includePath, $dir ) && is_readable( $includeFile ) )
     {
      include $includeFile;
     }
    }
}

But feel free to improve upon this if you see a shortcut.

Answer 2

You could 'try' this ;)

<?php

function exceptions_error_handler($severity, $message, $filename, $lineno) {
    throw new ErrorException($message, 0, $severity, $filename, $lineno);
}
set_error_handler('exceptions_error_handler');
try {
    include 'somefile.php';
    $included = true;
} catch (Exception $e) {
    // Code to run if it didn't work out
    $included = false;
}
echo 'File has ' . ($included ? '' : 'not ') . 'been included.';
?>

If it doesn't work, $included will be set to true, and then to false in the catch. If it did work, $included remains true.

Answer 3

You could try using stat to achieve the same effect as is_readable which I hear is very buggy when base dir is set.