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Re: [Full-disclosure] Possibility to exploit bash "*" processing



On 2011-09-21, at 09:55, Valdis.Kletnieks@xxxxxx wrote:
> On Wed, 21 Sep 2011 16:01:24 +0300, Dan Carpenter said:
>> Seems like a good time to promote David Wheeler's filename proposal:
>> http://www.dwheeler.com/essays/fixing-unix-linux-filenames.html
> 
> Unfortunately, David Wheeler's proposal has some implementation issues:
> 
> 1. Forbid/escape ASCII control characters (bytes 1-31 and 127) in filenames,
> including newline, escape, and tab.
> 
> 3. Forbid/escape filenames that aren't a valid UTF-8 encoding.
> 
> The problem is that the UTF-8 codespace consists *mostly* of multibyte
> characters, wherein at least one of the bytes, when considered by itself, is 
> an
> ASCII control character.

Not true - the multibyte sequences in UTF-8 text consist entirely of high-bit 
characters (0xC2 - 0xF4 initial, 0x80 - 0xBF continuation). All characters 
below 0x80, including ASCII control characters, are always mapped directly to 
the corresponding codepoints.
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