Re: Use of 1*DIGIT

On Dec 21, 2006, at 3:21 PM, Paul Leach wrote:
> In this case, a 64 bit implementation could handle lengths that a 32
> versions couldn't.
>
> I don't see that we need to note every place in the syntax where this
> problem could arise, just like we don't need to be explicit that
> implementers shouldn't code buffer overflows.

Right.  It is actually more dangerous for implementers to have
required size limitations in the protocol, since then they often
assume the value is going to remain conformant to the standard
(and we all know that isn't a constraint on attackers).

Implementions need to handle large numeric strings no matter how
large they might be, regardless of what the protocol says they
should be, and generally do so by returning an error if the
number is larger than the maximum for the internal representation
used for the value.  This will change over time (as data get bigger)
and may be much larger for specialized implementations than it
would be for general-purpose implementations.  10 years ago almost
everyone thought that 4GB would be a reasonable limit for an
implementation of Content-Length -- now that is clearly not the
case for the video-on-demand folks.

....Roy

Received on Friday, 22 December 2006 00:10:13 UTC