[websec] Font sniffing

"Anne van Kesteren" <annevk@opera.com> Tue, 25 January 2011 12:13 UTC

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Date: Tue, 25 Jan 2011 13:16:20 +0100
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From: "Anne van Kesteren" <annevk@opera.com>
Organization: Opera Software
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Subject: [websec] Font sniffing
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Due to nobody taking specifying media types, Content-Type for fonts is a  
lost cause. They probably need a loading context similar to images which  
the @font-face specification should use at some point.

Here are the signatures that Opera handles:

   0x74746366 'ttcf' (TTC; TrueType Collection)
   0x4F54544F 'OTTO' (OTF; OpenType)
   0x00010000        (TTF; TrueType)
   0x774F4646 'wOFF' (WOFF; Web Open Font Format)

For WOFF application/font-woff is being registered it seems, but nobody  
enforces that to my knowledge. I.e. user agents sniff.


In case it was unclear this is feedback on  
http://tools.ietf.org/html/draft-ietf-websec-mime-sniff :-)


-- 
Anne van Kesteren
http://annevankesteren.nl/