dl Download Ticket Service 0.1

dl Download Ticket Service project is a minimalist and rough download ticket service with automatic expiration, written in PHP. Ive been using this service as an email-attachment replacement for my company, but there are no plans on extending it. It will remain minimal: no fancy features, just bug fixes.
Installation:
Copy the "htdocs" directory to a directory of choice under your web server. Configure the needed parameters inside "include/config.php" to reflect the external url, main password, etc. The "include" directory must not be accessible: if you use apache, the included .htaccess file should be sufficient; consult your web server documentation otherwise.
A spool directory outside of the web server root must be accessible to the web server process. In the example "include/config.php" this is configured as "/var/spool/dl". If you web server runs as "nobody:nogroup", issue:
mkdir -p -m770 /var/spool/dl
chgrp nogroup /var/spool/dl
to create correctly this directory.
The maximal upload limit is determined by several PHP configuration parameters:
file_uploads: must be "On".
upload_tmp_dir: ensure enough space is available.
upload_max_filesize: change as needed.
post_max_size: must be at least 1M larger than upload_max_filesize.
The upload limit as shown in the submission form is determined automatically from the upload_max_filesize parameter. You can also set these parameters with ini_set() inside "include/config.php" or through apaches directives to localize them to the installation path.
There are several bugs in the dba_open() function in PHP 4.x which cannot be fixed. If you can, upgrade PHP to at least 4.3.5. If you cannot upgrade, you need to configure the "$dbHandler" parameter to something available to your PHP installation (usually db3/db2/dbm) and use the Berkeleys DB "db4_load" utility to create an empty database:
echo | db4_load /var/spool/dl/data.db
echo | db4_load /var/spool/dl/user.db
chmod 770 /var/spool/dl/*.db
chgrp nogroup /var/spool/dl/*.db
Depending on your system, you may have to use "db3_load/db2_load/etc" instead of "db4_load". Sometimes these utilities are part of "db*-util" packages under several linux distributions. If you have PHP 4.3.5 or greater, this is done automatically.
Ticket expiration is performed automatically when any web page is requested. This means that expired downloads will still occupy space on the spool directory until a web page is first serviced. If you need to ensure that the spool is purged regularly (for very low traffic servers), setup a scheduled job that requests the "http://dl.example.com/d/" page. Under UNIX, setup a cron entry like this:
0 0 * * * wget -q -O /dev/null "http://dl.example.com/d/" > /dev/null
Version restrictions:
- Tested with all mayor and minor browsers.
- Tested with PHP 4.2/4.3.
- Byte ranges are currently not supported.
- The submit button is not disabled correctly with Internet Explorer 6 (works on other graphical browsers however).