random mimetype?!

Anon

Hi all!

I stumbled over a strange phenomenon:
I have a <INPUT TYPE="FILE"> field and upload a file to the server.
There PHP kicks in and is supposed to proceed according to mimetype.

Allowed files are .php/.inc files on one hand and .zip on the other. Depending on which browser I use PHP detects different MIME Types. MSIE for example sends .php files as application/octet-stream (?!) while Netscape uses application/x-unknown-content-type-php_auto_file.
For .zip files Netscape uses application/octet-stream while MSIE uses the correct type (don#t have it in mind right now).

Is there a solution for this? (Esp. a better one than comparing file-extensions.)

Thanks in advance,

Dominique

brandonschnell

you can't trust the client browser to send the correct mime type. this has always been a problem. just don't filter file uploads by mime type.

Anon

just don't filter file uploads by mime type.

Hehe that's impossible...
A single PHP file will just be moved into a specific directory, a zip file will be moved into the directory below and will be unzipped there so that it's content is spread among serveral directories... it's completely different behavior so I need to be absolutelly sure which mimetype it is.

In the meanwhile I tried fiddling with apaches mime.types file. I tried adding the "php" and "inc" extensions to test/html and several other things but PHP seems to ignore or not to use that.

Ain't there a PHP- or even a bashfunction to determine MIME? In lack of buitin zip handling functions (PHP 4.0.4pl1) I use the exec() and passthru() functions a lot so a systemfunction (Redhat 6.2) wouldn't hurt...

Thanks again,

Dominique

brandonschnell

the remote clients web browser sets the mime type of the file being uploaded. if you want to filter the files by mime type you'll need to configure the mime types on every computer that might possibly upload to your site.

with the exception of macs, most client computers will use the file extensions to determine the mime type. IE mime types default to the windows file types. netscape has its own set of mime types. using a program to set the mime type will only work correctly if the program examines the file contents for the actual file type.