Re: Permitted characters in HTTP/2 fields

--------
Willy Tarreau writes:
> Hi Martin,
>
> On Thu, May 20, 2021 at 02:34:15PM +1000, Martin Thomson wrote:
> > Coming back to this.
> > 
> > Mark points out that if the purpose of these rules is to cut back on ways in
> > which smuggling might occur (not prevent, that's a fool's errand), then we
> > should also prohibit 0x00-0x1f and 0x7f (the ASCII control characters) and
> > 0x20 (SP) from field names.  I think that's reasonable, but I want to check
> > here.  That shouldn't make this harder to implement and it might catch some
> > genuine problems.
>
> I really agree. I don't remember if 0x80 and above are forbidden in H2 but
> I'd personally prefer to block them so that we don't needlessly introduce
> the risk of aliasing due to different codings being used. Protocol elements
> that define how messages should be delimited/routed/etc must be strictly
> defined and easy to enforce in implementations and applications.

+1

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Received on Thursday, 20 May 2021 18:02:25 UTC