Re: MAX_FILE_SIZE not working with file uploads

From: Date: Sun, 23 Sep 2007 04:26:58 +0000
Subject: Re: MAX_FILE_SIZE not working with file uploads
References: 1 2 3 4  Groups: php.general 
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Ray wrote:
On Saturday 22 September 2007 7:39:01 pm Dan Parry wrote:
This would be the exploitable 'feature' I mentioned... Client-side files should never be readable Dan
If the contents of a file were readable, I would definitely agree with you. I'm not convinced that the ability to detect the filesize of a file that the user selected would be exploitable, but it's a moot point as it doesn't work in javascript. (as someone else pointed out, maybe activeX?)
If Javascript can read the *directory* (and, thus, the size of the file) i'd be a bit nervous about that.
I'm not a javaScript expert, but I am learning, so I dug out the book, and put together the following script. (Ugly, insecure, and doesn't really do anything, but quick and It works, at least on my machine/browser combo) Select a file, and the page will tell you everything It can about the file. My machine reports size as zero.
Wouldn't that suggest that it's not working, then? ;-) Anyway, your script is interrogating the file *input element*, not the file, itself. Where you're trying to get the file size (document.test.fileTest.size) you're actually grabbing the value of the input's "size" attribute, which has a default of 0. You'll see this if you edit the input to have, eg. size="100" brian

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