Re: Whitespace before responses

On 9/02/2012 8:01 p.m., Willy Tarreau wrote:
> Hi Amos,
>
> On Thu, Feb 09, 2012 at 05:33:57PM +1300, Amos Jeffries wrote:
>> Willy, the rest of the thread is about *request* not response.
> No, look at the subject :-) The initial text covered only requests
> and Mark asked if we should cover responses too.

:-( /egg

>> Squid has
>> not accepted response whitespace prefixes in a very long time and bug
>> reports about that are very rare.
> Excellent ! In my opinion, Squid certainly qualifies as a reference for
> something widely used. So if you don't have the issue, I think it means
> the issue does not really exist, so we don't need to skip any CRLF before
> a response.

I suppose its also worth noting that the particular response code in 
Squid is also violating the RFC by disallowing SP characters before the 
"HTTP/1." string. With same lack of problems. It would be nice to drop 
that requirement on the response line out of the spec if it is still there.

>
>> Squid does skip whitespace at the beginning of the request and in my
>> recent experience it seems to be an active problem with scripts and
>> certain poular PDF readers.
> Same here. I've recently received a trace of a request emitted by a browser
> announcing webkit in its UA, I believe it was Safari, where a POST request was
> sent, then a few tens of milliseconds later, a CRLF was sent in a lone packet
> while it was not part of the message-body. So I can confirm this is observed
> from time to time. I'll see if I can find the capture so that we get the exact
> UA, maybe it was old and has been fixed since.

Shockwave Flash has one report here 
http://bugs.squid-cache.org/show_bug.cgi?id=2829. Not sure if that was 
Flash itself or a badly coded app.

I only encountered PDF in help forum discussions, so no idea which is 
was exactly.


AYJ

Received on Thursday, 9 February 2012 12:47:56 UTC